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  • Polymer and Materials Science  (112,478)
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  • 201
    Electronic Resource
    Electronic Resource
    Investigation of the microstructure of metallocene-catalyzed norbornene-ethylene copolymers using NMR spectroscopy (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1633-1638 
    Details
    ISSN: 0887-624X
    Keywords: cyclic olefin copolymers ; norbornene ; metallocene catalysts ; NMR ; microstructure ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Norbornene-ethylene copolymers were prepared using the metallocene catalyst ethylene bis (indenyl) zirconium dichloride with MAO, and their microstructure was characterized with 1H-NMR and 13C-NMR methods. From a Cosy 1H-NMR spectrum it was found that all norbornene units are enchained in the exo-configuration. The sequence distribution of norbornene units was investigated using 13C-1H correlations, hmqc for one-bond correlations, and hmbc for two- or three-bond correlations. It was shown that norbornene diads were formed at a high norbornene content (45 mol %). When further increasing the norbornene incorporation (66 mol %) a number of new signals were obtained. A Cosy 1H-NMR spectrum revealed a new crosspeak which, according to the corresponding 13C-NMR shifts (hmqc), correlated well with a terminal unit of a trimer of norbornene. This means that at very high norbornene contents, norbornene triads can be formed. Because the formation of isotactic norbornene triads is very difficult to understand from a sterical point of view, an epimerization process causing stereoirregularities in the norbornene triad is proposed. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1633-1638, 1998
    Additional Material: 8 Ill.
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  • 202
    Electronic Resource
    Electronic Resource
    Syntheses and biological activities of α-methoxy-3,6-endo-methylene-1,2,3,6-tetrahydrophthaloyl-5-fluorouracil and its polymers (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1625-1632 
    Details
    ISSN: 0887-624X
    Keywords: α-methoxy-3,6-endo-methylene-1,2,3,6-tetrahydrophthaloyl-5-fluorouracil (MMTFU) ; poly(MMTFU-co-AA) ; poly(MMTFU-co-VAc) ; photopolymerization ; average molecular weight ; in vitro cytotoxicity ; in vivo antitumor activity ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The new monomer, α-methoxy-3,6-endo-methylene-1,2,3,6-tetrahydrophthaloyl-5-fluorouracil (MMTFU), was synthesized from 5-fluorouracil (5-FU) and α-methoxy-3,6-endo-methylene-1,2,3,6-tetrahydrophthaloyl chloride (MMTC). Poly(α-methoxy-3,6-endo-methylene-1,2,3,6-tetrahydrophthaloyl-5-fluorouracil) [poly(MMTFU)], poly(α-methoxy-3,6-endo-methylene-1,2,3,6-tetrahydrophthaloyl-5-fluorouracil-co-acrylicco-AA), and poly(α-methoxy-3,6-endo-methylene-1,2,3,6-tetrahydrophthaloyl-5-fluorouracil-co-vinyl acetate) [poly(MMTFU-co-VAc)] were synthesized by photopolymerizations using 2,2-dimethoxy-2-phenylacetophenone (DMP) as the photoinitiator. The synthesized MMTFU and the polymers were identified by FT-IR, 1H-NMR, and 13C-NMR spectroscopies. The contents of MMTFU in poly(MMTFU-co-AA) and poly(MMTFU-co-VAc) determined by elemental analysis were 63 and 57 mol %, respectively. The number average molecular weights and polydispersity indices of synthesized polymers determined with GPC were in range of 7,700-19,100 and 1.6-2.7. The in vitro cytotoxicities of samples were evaluated with mouse mammary carcinoma (FM3A), mouse leukemia (P388), and human histiocytic lymphoma (U937) as cancer cell lines and mouse liver cells (AC2F) as a normal cell line. The cytotoxicities of 5-FU and synthesized samples against cancer cell lines increased in following orders: 5-FU 〉 MMTFU 〉 poly(MMTFU) 〉 poly(MMTFU-co-AA) 〉 poly(MMTFU-co-VAc). The in vivo antitumor activities of the synthesized samples against mice bearing the sarcoma 180 tumor cell line were evaluated. The in vivo antitumor activities of the polymers were greater than that of 5-FU at a dose of 80 mg/kg. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1625-1632, 1998
    Additional Material: 2 Ill.
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  • 203
    Electronic Resource
    Electronic Resource
    Polymerization of acrylates by atom transfer radical polymerization. Homopolymerization of 2-hydroxyethyl acrylate (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1417-1424 
    Details
    ISSN: 0887-624X
    Keywords: 2-hydroxyethyl acrylate ; poly(2-hydroxyethyl acrylate) ; atom transfer radical polymerization (ATRP) ; controlled free radical polymerization ; MALDI-MS ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The application of atom transfer radical polymerization (ATRP) to the homopolymerization of 2-hydroxyethyl acrylate, a functional monomer, is reported. The polymerizations exhibit first-order kinetics, and molecular weights increase linearly with conversion. Polydispersities remain low throughout the polymerization (Mw/Mn ≈ 1.2). Reactions were conducted in bulk and in 1 : 1 (by volume) aqueous solution; the latter demonstrates the resilience of ATRP to protic media. Analysis of poly(2-hydroxyethyl acrylate) by MALDI-MS and 1H-NMR shows Mn,exp to be much closer to Mn,th than those observed by SEC using polystyrene standards. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1417-1424, 1998
    Additional Material: 4 Ill.
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  • 204
    Electronic Resource
    Electronic Resource
    Hyperbranched polymers 10 years after (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1685-1698 
    Details
    ISSN: 0887-624X
    Keywords: hyperbranched polymer ; dendrimers ; comb-burst dendrimers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: It has been about 10 years since the first intentional preparation of hyperbranched polymer was disclosed. Hyperbranched polymers, as well as dendrimers, may find utilities in the areas where the structural uniqueness of these polymers gives merit. There has been much progress in the structural understanding and the methods of synthesis of these polymers. However, functional understanding and utility of these polymers are still in infancy. Better understanding on physical properties of these polymers, such as solubility and miscibility of these polymers in solvents or with polymers, and functional group dependency to the thermal relaxation process are needed for further development of the subject. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A: Polym. Chem. 36: 1685-1698, 1998
    Additional Material: 4 Tab.
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  • 205
    Electronic Resource
    Electronic Resource
    Copolymerization of dienes with neodymium tricarboxylate-based catalysts and cis-polymerization mechanism of dienes (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1707-1716 
    Details
    ISSN: 0887-624X
    Keywords: neodymium tricarboxylate ; cis-poly (2,3-dimethylbutadiene) ; copolymerization of dienes ; cis-1,4 polymerization mechanism ; back-biting coordination ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: It was found that poly(butadiene), poly(isoprene), and poly(2,3-dimethylbutadiene) with high cis-1,4 content were obtained with Nd(OCOR)3-(i-Bu)3Al-Et2AlCl catalysts (R = CF3, CCl3, CHCl2, CH2Cl, CH3) in hexane at 50°C [cis-1,4 content: poly(BD), 〉 98%; poly(IP), ≥ 96%; poly(DMBD), ≥ 94%]. Copolymerization of IP and styrene (St) was carried out at various monomer feed ratios to evaluate the monomer reactivity ratio and cis-1,4 content of the diene unit and then to elucidate the cis-1,4 polymerization mechanism of IP. The cis-1,4 content of the IP unit in the copolymers decreased with increasing St content in the copolymers. The cis-1,4 polymerization was disturbed by incorporating St unit in the copolymers, since the penultimate St unit hardly coordinates to the neodymium metal, resulting in a decrease of the cis-1,4 content in the copolymers. That is, the cis-1,4 polymerization of IP is suggested to be controlled by a back-biting coordination of the penultimate diene unit. On the other hand, in the case of poly(BD-co-IP) and poly(BD-co-DMBD), the cis-1,4 content of the BD, IP, and DMBD units in the copolymers was almost constant (cis: 94-98%), irrespective of the monomer feed ratios and polymerization temperature. Consequently, the penultimate IP and DMBD units favorably control the terminal BD, IP, or DMBD unit to the cis-1,4 configuration through the back-biting coordination. For the monomer reactivity ratios, a clear difference was observed in each system: rBD = 1.22, rIP = 1.14; rBD = 40.9, rDMBD = 0.15. Low polymerizability of DMBD was mainly ascribed to the steric effect of the methyl substituents. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1707-1716, 1998
    Additional Material: 6 Ill.
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  • 206
    Electronic Resource
    Electronic Resource
    Microstructure effect in the coupling reactions of polymeric organolithium compounds using chlorosilanes (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1743-1753 
    Details
    ISSN: 0887-624X
    Keywords: coupling reaction ; living polymer ; microstructure ; coupling yield ; 1,4-enchainment ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The most important variable affecting the yield in the coupling reactions of polymeric organolithium compounds with chlorosilane compounds has been investigated through size-exclusion chromatographic (SEC) analysis. The coupling reaction of poly(styryl)lithium with dichlorodimethylsilane as a silane-coupling agent provided 44 wt % of the coupling yield. The coupling yield, depending on the chain end reactivity of active polymers, was not greatly affected. The addition of a Lewis base such as N,N,N′,N′-tetramethylethylenediamine (TMEDA) even after complete polymerization of the dienes in hydrocarbon seems to affect the coupling reaction, resulting in decreasing the yield. The 1,2- or 3,4-enchain contents in the polydiene backbones affected the reduction of the linking efficiency in the coupling of the poly(dienyl)lithiums with chlorosilanes as the linking agent. The linking yields of the active polymers including over 75 mol % of 1,2- or 3,4-enchainment on the polydiene segment were below 20 wt %. The linking yields exhibited a dependence not only on the steric requirement of the chain end, but also the microstructure of the polydiene segment. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1743-1753, 1998
    Additional Material: 5 Ill.
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  • 207
    Electronic Resource
    Electronic Resource
    Synthesis and properties of novel polymers having S-methyldibenzothiophenium salt moieties (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1779-1784 
    Details
    ISSN: 0887-624X
    Keywords: poly(sulfonium salt) ; poly(2-vinyldibenzothiophene) ; 5-methyl-2-vinyldibenzothiophenium tetrafluoroborate ; sulfonium monomer ; radical polymerization ; polymer reaction ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A polymer having dibenzothiophenium salt moieties [poly(sulfonium salt), 2] was prepared by the reaction of poly(2-vinyldibenzothiophene) (1) with CH3I and AgBF4 in CH2ClCH2Cl at room temperature for 24 h. The obtained polymer 2 was found to contain 71% of the methyldibenzothiophenium tetrafluoroborate unit. A monomer carrying the sulfonium salt moiety, i.e., 5-methyl-2-vinyldibenzothiophenium tetrafluoroborate (4), was independently prepared and subjected to radical polymerization to give a polymer (5) in 88% yield (methyldibenzothiophenium tetrafluoroborate unit: 79%). The thermal decompositions of 2 and 5 took place in two steps; the first step involved the formation of polymer 1 by demethylation. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1779-1784, 1998
    Additional Material: 3 Ill.
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  • 208
    Electronic Resource
    Electronic Resource
    Influence of plasma treatment on the molar mass of poly(ethylene terephthalate) investigated by different chromatographic and spectroscopic methods (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1639-1648 
    Details
    ISSN: 0887-624X
    Keywords: poly(ethylene terephthalate) (PET) ; plasma ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The influence of different types of low and atmospheric pressure plasma on poly(ethylene terephthalate) (PET) has been studied in terms of changes in molar mass and molar mass distribution. Apart from a variation of plasma gases (oxygen, helium) different types of plasma (microwave, radio frequency, corona discharge) were used for the plasma surface modification. The changes in molar mass and types of functional end groups of lower molar mass products were investigated by means of matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOFMS), whereas the high-molar mass fraction was analyzed by means of size-exclusion chromatography (SEC). The formation of crosslinked products during exposure to a helium plasma, which emits preponderately energy-rich and intense ultraviolet radiation, was proved by means of thermal field-flow fractionation (ThFFF). This method combined with a multiangle laser light scattering (MALLS) detector allows detection of weakly crosslinked polymers and microgels. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1639-1648, 1998
    Additional Material: 9 Ill.
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  • 209
    Electronic Resource
    Electronic Resource
    Synthesis and characterization of poly(benzobisthiazole) with tetramethylbiphenyl moiety in the main chain (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1407-1416 
    Details
    ISSN: 0887-624X
    Keywords: PBZT ; polycondensation ; tetramethylbiphenyl substituted ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(benzobisthiazole)s containing an ortho-tetramethyl substituted biphenyl moiety were synthesized via the polycondensation of 2,5-diamino-1,4-benzenedithiol dihydrochloride with 2,2′,6,6′-tetramethylbiphenyl-4,4′-dicarboxylic acid in poly(phosphoric acid) (PPA). The intrinsic viscosities of the tetramethylbiphenyl poly-(benzobisthiazole)s in chlorosulfonic acid at 30°C were in the range of 6.9-13.4 dL/g. Copolycondensation of 2,5-diamino-1,4-benzenedithiol dihydrochloride with terephthalic acid and 2,2′,6,6′-tetramethylbiphenyl-4,4′-dicarboxylic acid was carried out as well by varying the ratio of the two dicarboxylic acid monomers in the reactant mixture. The homopolymers and copolymers were characterized by Fourier transform infrared spectroscopy (FTIR) and 13C solid-state nuclear magnetic resonance spectroscopy (NMR). Thermal stability of the polymers was evaluated by thermogravimetric analysis (TGA) and thermogravimetric mass spectrum analysis (TG-MS). The tetramethylbiphenyl poly(benzobisthiazole)s were found to be more stable at elevated temperatures than the parent poly(p-phenylene benzobisthiazole) (PBZT). © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1407-1416, 1998
    Additional Material: 6 Ill.
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  • 210
    Electronic Resource
    Electronic Resource
    Novel aromatic polyhydrazides and poly(amide-hydrazide)s based on “multiring” flexible dicarboxylic acids (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1847-1854 
    Details
    ISSN: 0887-624X
    Keywords: polyhydrazides ; poly-1,3,4-oxadiazoles ; thermal behavior ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two flexible dicarboxylic acid monomers, 4,4′-[isopropylidenebis(1,4-phenylene)dioxy]dibenzoic acid (1) and 4,4′-[hexafluoroisopropylidenebis(1,4-phenylene)-dioxy]dibenzoic acid (3), were synthesized from readily available compounds in two steps in high yields. High molecular-weight polyhydrazides and poly(amide-hydra-zide)s were directly prepared from dicarboxylic acids 1 and 3 with terephthalic dihydrazide (5), isophthalic dihydrazide (6), and p-aminobenzhydrazide (7) by the phosphorylation reaction by means of diphenyl phosphite (DPP) and pyridine in N-methyl-2-pyrrolidone (NMP)/LiCl, or prepared from the diacyl chlorides of 1 and 3 with the hydrazide monomers 5-7 by the low-temperature solution polycondensation in NMP/LiCl. Less favorable results were obtained when using triphenyl phosphite (TPP) instead of DPP in the direct polycondensation reactions. Except for those derived from terephthalic dihydrazide, the resulting polyhydrazides and poly(amide-hydrazide)s could be cast into colorless, flexible, and tough films with good tensile strengths. All the hydrazide polymers and copolymers are amorphous in nature and are readily soluble in various polar solvents such as NMP and dimethyl sulfoxide (DMSO). Their Tgs were recorded in the range of 162-198°C and could be thermally cyclodehydrated into the corresponding polyoxadiazoles and poly(amide-oxadiazole)s approximately in the region of 300-380°C, as evidenced by the DSC thermograms. The oxadiazole polymers and copolymers showed a dramatically decreased solubility and higher Tg when compared to their respective hydrazide prepolymers. They exhibited Tgs of 190-216°C and were stable up to 450°C in air or nitrogen. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1847-1854, 1998
    Additional Material: 4 Ill.
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  • 211
    Electronic Resource
    Electronic Resource
    Novel polyisobutylene/poly(dimethylsiloxane) bicomponent networks. I. Synthesis and characterization (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1891-1899 
    Details
    ISSN: 0887-624X
    Keywords: polyisobutylene ; poly(dimethylsiloxane) ; hydrosilation ; bicomponent networks ; molecular weight between crosslinks ; network functionality ; sol fraction ; extractables ; model networks ; end-linking ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of novel polyisobutylene (PIB)/poly(dimethylsiloxane) (PDMS) bicomponent networks is described. The synthesis strategy (see Figure 1) was to prepare well-defined and -characterized allyl-tritelechelic polyisobutylenes [φ(PIB - C - C=C)3] and SiH-ditelechelic poly(dimethylsiloxanes) (HSi-PDMS-SiH) and then crosslink these moieties by hydrosilation. The φ(PIB - C - C=C)3 was prepared by living isobutylene polymerization followed by end-quenching with allyltrimethylsilane, whereas the HSi-PDMS-SiH was obtained by equilibrium polymerization of octamethylcyclotetrasiloxane and tetramethyldisiloxane. The detailed structures of the starting polymers were characterized by GPC and 1H-NMR spectroscopy. A series of PIB/PDMS bicomponent networks of varying compositions and average molecular weights between crosslinks (Mc) of ∼ 20,000 g/mol were assembled. Optimum crosslinking conditions were defined in terms of H2PtCl6 catalyst concentration, nature of solvent, time, temperature, and stoichiometry of ∼ CH2CH=CH2/∼SiH groups, allowing for the convenient synthesis of well-defined model bicomponent networks. Swelling studies and elemental analysis confirm the correctness of the synthetic strategy. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1891-1899, 1998
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  • 212
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    Electronic Resource
    Novel polyisobutylene/poly(dimethylsiloxane) bicomponent networks. II. Network structure and property characterization (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1901-1910 
    Details
    ISSN: 0887-624X
    Keywords: polyisobutylene ; poly(dimethylsiloxane) ; bicomponent networks ; network structure ; molecular weight between crosslinks ; network properties ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The first part of this series concerned the synthesis of novel polyisobutylene (PIB)/poly(dimethylsiloxane) (PDMS) bicomponent networks; the present paper concerns the structure and property characterization of a series of bicomponent networks of varying compositions (PIB wt %/PDMS wt % = 92/8, 70/30, 50/50, 35/65) having average molecular weights between crosslinks (Mc) of ˜ 20,000 g/mol. According to network structure analysis by uniaxial equilibrium stress-strain measurements, the experimental Mc's are in excellent agreement with theoretical values. Hydrosilation end-linking efficiency was quantitated by the amount of sol and functional group analysis by 1H-NMR spectroscopy. NMR evidence indicates double-bond isomerization during hydrosilation. Network compositions by elemental analysis together with the low sol fractions indicate efficient crosslinking. These data suggest highly efficient network formation and well-defined bicomponent network structures. While PIB and PDMS showed Tg's at -72 and -124°C, respectively, the bicomponent network did not exhibit clearly discernible phase transitions. The heat stability of bicomponent networks increased slightly with increasing PDMS content showing initial (10%) degradation temperatures at ˜ 380°C in nitrogen and ˜ 320°C in air. Tensile strengths and elongations were dependent on composition and varied in the 0.6-3.8 MPa and 600-1100% ranges, respectively. The swelling behavior was not much affected by composition. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1901-1910, 1998
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  • 213
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    Electronic Resource
    Synthesis of aromatic polyesters and polyamides by alternating copolymerizations of 1,4-dicarbonyl-1,4-dihydronaphthalene with bezoquinones and benzoquinone diimines (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1929-1936 
    Details
    ISSN: 0887-624X
    Keywords: aromatic bisketene ; aromatic polyesters ; aromatic polyamides ; addition reaction ; benzoquinones ; benzoquinone diimines ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1,4-Dicarbonyl-1,4-dihydronaphthalene (1) was synthesized by the dehydrochlorination reaction of 1,4-dihydronaphthalene-1,4-dicarbonyl chloride with triethylamine and obtained as its very dilute solution, but it easily polymerized in the concentration as high as 0.1 mol/L to give its polymer. 1 generated in situ by the dehydrochlorination reaction of 1,4-dihydronaphthalene-1,4-dicarbonyl chloride in a deoxygenated toluene polymerized alternatingly with benzoquinones such as 2-dodecylthio-p-benzoquinone, 2,5-di(tert-butyl)-p-benzoquinone, p-benzoquinone, and 2,3-dichloro-5,6-dicyano-p-benzoquinone, and with benzoquinone diimines such as N,N′-diethoxycarbonyl-p-benzoquinone diimine, N,N′-dibenzoyl-p-benzoquinone diimine, and N,N′-diphenyl-p-benzoquinone diimine to give aromatic polyesters and polyamides, respectively. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1929-1936, 1998
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  • 214
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    Electronic Resource
    Polymerization of epoxide by a fluorenyltriphenylphosphonium salt as a thermally latent initiator (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1957-1960 
    Details
    ISSN: 0887-624X
    Keywords: cationic polymerization ; thermally latent initiator ; fluorenyltriphenylphosphonium salt ; epoxide ; glycidyl phenyl ether ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
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  • 215
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    Electronic Resource
    Aminolysis kinetics of model and polymer-bound anhydride moieties in low- and high-viscosity media (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1573-1582 
    Details
    ISSN: 0887-624X
    Keywords: amic acid ; secondary amine ; maleic anhydride ; melt reaction kinetics ; model compounds ; polymer-bound functional groups ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This study examines the legitimacy of using the reaction kinetics of low molecular weight model compounds in solution to predict the chemical kinetics of polymer-bound species in a homogeneous melt. The reaction under study takes place between an aliphatic secondary amine, diisooctadecylamine (DiOA), and a 5-membered anhydride ring, saturated maleic anhydride (MA), forming an amic acid product. The MA species was present as a pendant graft on either a model compound, dodecane-g-(maleic anhydride) (dodecane-g-MA), or a polymer chain, linear low-density polyethylene-g-(maleic anhydride) (LLDPE-g-MA). Pseudo-second-order kinetics of the anhydride consumption are followed by infrared spectroscopy, either in situ in dodecane solution or by scanning frozen film samples taken from a linear low-density polyethylene melt. It was found that the LLDPE-g-MA/DiOA system reacted at a slightly slower rate than the dodecane-g-MA/DiOA system in the low-viscosity solution at 140°C. In the melt, the dodecane-g-MA/DiOA system experienced a small decrease in the overall reaction rate compared to the same reaction carried out in dodecane. However, the LLDPE-g-MA/DiOA system underwent a 65% decrease in the observed second-order rate constant on going from a solution to the melt. To explain these phenomena, the effects of diffusion, miscibility, and chain entanglements in the melt are examined here. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1573-1582, 1998
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  • 216
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    On-line monitoring, modeling, and model validation of semibatch emulsion polymerization in an automated reactor control facility (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1553-1571 
    Details
    ISSN: 0887-624X
    Keywords: seeded emulsion polymerization ; gel effect ; radical entry ; particle size sensor ; semibatch model ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The modeling of the semibatch emulsion polymerization of styrene and its validation against data obtained from a reactor facility is presented. The model, which describes the growth of a monodisperse polystyrene seed as neat monomer is fed to the reactor, incorporates recent findings in radical diffusion and kinetics. The current controversy surrounding radical absorption into particles is handled by considering absorption via propagation, diffusion, and collision in the model. Simulation results including weight fraction polymer inside the particles and particle diameter are compared to data obtained from a custom-designed and built automated reactor control facility capable of on-line density and on-line particle diameter measurements. Good agreement between simulation results and experimental data are obtained for any of the three absorption mechanisms considered by varying only one adjustable parameter located in the absorption rate coefficient relation. A sensitivity analysis of the model to this adjustable parameter, using the program ODESSA, is also presented and shown to be an important tool in the validation procedure. Lastly, an analysis of the dynamics of the process shows the variety of phenomena that can be obtained in a semibatch reactor including regions that exhibit pseudosteady states, autoacceleration of the rate, and limiting conversion. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1553-1571, 1998
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    Synthesis of poly(styrene-b-tetrahydrofuran-b-styrene) triblock copolymers by transformation from living cationic into living radical polymerization using 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl as a transforming agent (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2059-2068 
    Details
    ISSN: 0887-624X
    Keywords: poly(THF) ; TEMPO ; both the chain ends ; triblock copolymer ; living radical polymerization ; a transforming agent ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis of poly(styrene-b-tetrahydrofuran (THF)-b-styrene) triblock copolymers was performed by transformation from living cationic into living radical polymerization, using 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (4-hydroxy-TEMPO) as a transforming agent. Sodium 4-oxy-TEMPO, derived from 4-hydroxy-TEMPO, reacted with the living poly(THF), which was prepared by cationic polymerization of THF using trifluoromethanesulfonic acid anhydride as an initiator, resulting in quantitative formation of the poly(THF) with TEMPO at both the chain ends. The resulting polymers were able to serve as a polymeric counter radical for the radical polymerization of styrene by benzoyl peroxide, to give the corresponding triblock copolymer in quantitative efficiency. The polymerization was found to proceed in accordance with a living mechanism, because the conversion of styrene linearly increased over time, and the molar ratio of styrene to THF units in the copolymer also increased as a result of increasing the conversion. The TEM pictures demonstrated that the resulting copolymers promoted microphase segregation. It was found that the films of these copolymers showed contact angles intermediate between those of poly(THF) and of polystyrene. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2059-2068, 1998
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    Surface functionalization of polymer latex particles. III. A convenient method of producing ultrafine poly(methylstyrene) latexes with aldehyde groups on the surface (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2103-2109 
    Details
    ISSN: 0887-624X
    Keywords: functionalization of polymer latexes ; poly(methylstyrene) ; catalytic oxidation ; ultrafine particles ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A convenient method of preparing ultrafine poly(methylstyrene) (PMS) latex particles with aldehyde groups on the surface is developed. PMS latexes in the size range 33-81 nm were prepared via microemulsion polymerization, using cetyltrimethylammonium bromide (CTAB) as surfactant. The surface of the PMS latexes was oxidized in the presence of tert-butyl hydroperoxide catalyzed by copper(II) chloride. As the degree of oxidation increased up to 6 h, the amounts of aldehyde group increased. Bigger particles were found to have a slightly higher rate of oxidation than small ones under the same oxidation conditions. The particle size underwent little change during oxidation; thus, the amounts of functional groups and the particle size could be controlled concurrently. Dialysis study of the oxidized PMS microlatexes indicated that the instability of highly oxidized PMS microlatexes was caused by the reduction of total surface charge density due to the presence of carboxylic acid groups. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2103-2109, 1998
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    New synthetic route for weak base anion exchangers based on crosslinked polystyrene (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2151-2154 
    Details
    ISSN: 0887-624X
    Keywords: anion exchangers ; crosslinked polystyrene ; Friedel-Crafts acetylation ; Mannich amination ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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    Helix-sense-selective copolymerization of phenyl[bis(2-pyridyl)]methyl methacrylate, diphenyl(2-pyridyl)methyl methacrylate and triphenylmethyl methacrylate with chiral anionic initiators (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2127-2133 
    Details
    ISSN: 0887-624X
    Keywords: phenyl[bis(2-pyridyl)]methyl methacrylate ; (S)-(+)-1-(2-pyrrolidinylmethyl)pyridine ; anionic asymmetric copolymerization ; optically active copolymer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Optically active poly[triphenylmethyl methacrylate-co-phenyl[bis(2-pyridyl)]methyl methacrylate] (poly[TrMA-co-PB2PyMA], poly[diphenyl(2-pyridyl)methyl methacrylate-co-phenyl[bis(2-pyridyl)]methyl methacrylate] (poly[D2PyMA-co-PB2PyMA]), and poly[triphenylmethyl methacrylate-co-diphenyl(2-pyridyl)-methyl methacrylate] (poly[TrMA-co-D2PyMA]) were prepared by helix-sense-selective copolymerization with complexes of organolithium with (-)-sparteine [(-)Sp],(S, S)-(+)- and (R, R)-(-)-2,3-dimethoxy-1,4-bis(dimethylamino)butane [(+)- and (-)DDB], and (S)-(+)-2-(1-pyrrolidinylmethyl)pyridine [(+)PMP] as anionic initiators in toluene at low temperature. The copolymers obtained with (-)Sp and (+)DDB or (-)DDB complexes of organolithium showed low optical activity, but to [(+)PMP] complex with N,N′-diphenyleneamine monolithium amide [(+)PMP-DPEDA-Li)] was effective in synthesizing copolymers of high optical rotation ([α]25D about +320 to + 370°) which were comparable to those of corresponding homopolymers with one-handed helical structure. The optical rotations of poly[TrMA-co-PB2PyMA] and poly[TrMA-co-D2PyMA] were much more stable than that of poly(D2PyMA) or poly(PB2PyMA) in a solution of CHCl3-2,2,2-trifluoroethanol (10 : 1, v/v) at 25°C, but optical rotation of poly[D2PyMA-co-PB2PyMA] slowly decreased with time in the same conditions. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2127-2133, 1998
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    Preparation of poly(aryleneethynylene)-type copolymers containing flexible linking methylene units. Optical properties of the copolymers suggesting occurrence of energy transfer between π-conjugated local units (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2201-2207 
    Details
    ISSN: 0887-624X
    Keywords: poly(aryleneethynylene) ; palladium-catalyzed ; copolymer ; optical properties ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Palladium-catalyzed polycondensation between 2,5-diiodo-3-hexylthiophene I-Th(Hex)-I with mixtures of p-diethynylbenzene HC≡C - Ph - C≡CH and α,ω-diethynylalkane HC≡C(CH2)lC≡CH (l = 3 or 8) gives poly(aryleneethynylene) PAE-type copolymers [C≡C(CH2)lC≡C - Th(Hex)]m[C≡C - Ph - C≡C - Th(Hex)]n containing the methylene unit. The copolymers have a molecular weight (Mn) of about 1.2 × 104 as determined by GPC (polystyrene standard) and are considered to possess essentially a random sequences in view of the  - C≡C(CH2)lC≡C -  and  - C≡C - Ph - C≡C -  units as judged from their UV-visible spectra. By the incorporation of the (CH2)l unit, the λmax position of the corresponding PAE homopolymer [C≡C - Ph - C≡C - Th(Hex)]n is shifted to a shorter wavelength. However, the copolymers give rise to a photoluminescence PL peak essentially agreeing with a PL peak of the homopolymer, suggesting occurrence of energy transfer in the copolymer. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2201-2207, 1998
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    Photolysis of a fluorinated polymer film by vacuum ultraviolet radiation (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2215-2222 
    Details
    ISSN: 0887-624X
    Keywords: fluorinated polymer ; vacuum ultraviolet ; Xe lamp ; photolysis ; photo-oxidation ; surface modification ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: We studied the photolysis of a fluoroethylene-fluoropropylene copolymer (FEP) film by vacuum ultraviolet (VUV) radiation from a resonance Xe lamp at a wavelength of 147 nm and air pressures of 0.05 and 2.5 Torr. The chemical changes in the FEP surface layer were investigated by Fourier-transform infrared spectroscopy with attenuated total reflection attachment and X-ray photoelectron spectroscopy. Double bonds were found to be the main product in the case of VUV treatment at 0.05 Torr, while photo-oxidation of FEP occurred predominantly by VUV treatment at 2.5 Torr under formation of the  - CF2C(O)F group. This oxygen-containing group was more effectively formed in the FEP surface layer by VUV photo-oxidation than by conventional surface oxidation techniques such as treatments by plasma and corona discharge and ozone. Storage of the VUV-treated polymers in air at 50% relative humidity resulted in hydrolysis of  - CF2C(O)F to the  - CF2COOH group. Substantial improvement of the film wettability was noticed after VUV photo-oxidation. These findings suggest that VUV irradiation provides a high potential for surface modification of fluorinated polymers which are known to be particularly resistant against functionalization by conventional surface modification techniques such as plasma treatment. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2215-2222, 1998
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    A positive-working photosensitive alkaline-developable polyimide with a highly dimensional stability and low dielectric constant based on poly(amic acid) as a polyimide precursor and diazonaphthoquinone as a photosensitive compound (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2261-2267 
    Details
    ISSN: 0887-624X
    Keywords: photosensitive polyimide ; highly dimensional stability ; low dielectric constant ; poly(amic acid) ; diazonaphthoquinone ; positive type ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A positive-working photosensitive polyimide precursor based on fluorinated poly(amic acid) (FPAA) and 2,3,4-tris(1-oxo-2-diazonaphthoquinon-4-ylsulfonyloxy)benzophenone (D4SB) as a photosensitive compound has been developed. FPAA was prepared by ring-opening polyaddition of dianhydrides, pyromellitic dianhydride and biphenyltetracarboxylic dianhydride, with diamine, 2,2′-bis(trifluoromethyl)benzidine, in methanol. The FPAA film showed excellent transparency to UV light and good solubility in a wide range of organic solvents. The dissolution behavior of FPAA containing 30 wt % D4SB after exposure was studied, and it was found that the difference of dissolution rate between exposed and unexposed parts was enough to get high contrast due to the photochemical reaction of D4SB in the polymer film. The photosensitive fluorinated polyimide (FPI) precursor containing 30 wt % D4SB showed a sensitivity of 80 mJ cm-2 and a contrast of 7.8 with 365 nm light when it was developed with 0.3% aqueous tetramethyl ammonium hydroxide solution at room temperature. The FPI film cured up to 360°C had a low coefficient of thermal expansion of 10.3 ppm °C-1 and a low dielectric constant of 3.04. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2261-2267, 1998
    Additional Material: 9 Ill.
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    Synthesis and characterization of new poly(amide-imide)s from 1,4-bis(4-trimellitimidophenoxy)-2-tert-butylbenzene with various diamines (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2301-2307 
    Details
    ISSN: 0887-624X
    Keywords: 1,4-bis(4-trimellitimidophenoxy)-2-tert-butylbenzene (BTTB) ; direct polycondensation ; poly(amide-imide)s ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New poly(amide-imide)s were prepared from a diimide-dicarboxylic acid, 1,4-bis(4-trimellitimidophenoxy)-2-tert-butylbenzene (BTTB), with various diamines by the direct polycondensation in N-methyl-2-pyrrolidinone (NMP) using triphenyl phosphite and pyridine as condensing agents. The new diimide-dicarboxylic acid BTTB containing an ether linkage and tert-butyl substituent was synthesized by the condensation reaction of 1,4-bis(4-aminophenoxy)-2-tert-butylbenzene with trimellitic anhydride. All the polymers were obtained in quantitative yields with inherent viscosities of 0.62-1.06 dL g-1. The polymers were amorphous, and most of them were readily soluble in aprotic polar solvents such as NMP, N,N-dimethylacetamide (DMAc), and N,N-dimethylformamide (DMF), as well as in less polar solvents such as dimethyl sulfoxide (DMSO), m-cresol, pyridine, and γ-butyrolactone, and also even in tetrahydrofuran. The glass transition temperatures of the polymers were determined by DSC method, and they were in the range of 238-279°C. These polymers were stable up to 408-449°C in air and 451-483°C in nitrogen and lose 10% weight in the range of 479-525°C in air and 480-528°C in nitrogen atmosphere. The polymer films had a tensile strength range of 71-115 MPa, an elongation at break range of 4-14%, and a tensile modulus range of 2.3-3.1 GPa. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2301-2307, 1998
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    Synthesis and surface characterization of heparin-immobilized polyetherurethanes (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2331-2338 
    Details
    ISSN: 0887-624X
    Keywords: poly(ether urethane) ; surface modification ; heparin immobilization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Novel poly(ether urethanes) containing diester groups in the side chains (PU) were synthesized from 4,4′-diphenylmethyl diisocyanate, polytetramethylene glycol, and diethyl bis(hydroxymethyl)malonate as a chain extender. The surface modification of the PU film was carried out by a hydrolysis reaction, poly(ethylene oxide) (PEO) grafting, and heparin immobilization, and the surface-modified PUs were then characterized by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, electron spectroscopy for chemical analysis (ESCA), and a contact angle goniometer. The concentration of carboxylic acid groups introduced on the PU surfaces as determined by the rhodamine interaction method was 61 nmol/cm2 when treated with 4N NaOH/methanol (1 : 2 v/v) for 30 min and subsequently with a citric acid-methanolic aqueous solution. The amounts of heparin coupled to the carboxyl groups on the PU surfaces and to the terminus amino groups on the PU-PEO were 0.92 and 0.84 μ g/cm2, respectively. There was almost no heparin released from the immobilized surface of a physiological solution for 100 h, thereby indicating the strong stability of immobilized heparin. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2331-2338, 1998
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    A parametric study of the terminal maleation of polypropylene through an Alder Ene reaction (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2371-2380 
    Details
    ISSN: 0887-624X
    Keywords: Alder Ene reaction ; polypropylene ; Lewis acid ; maleation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A study of the parameters that affect the Alder Ene reaction with respect to the synthesis of a terminally anhydride-functionalized polypropylene was carried out over a temperature range of 220-250°C using maleic anhydride concentrations of 2-12 mol equivalence with respect to the vinylidene group. As previously observed, a Lewis acid (i.e., SnCl2 · 2H2O) had a catalytic effect on the reaction at these temperatures, thereby improving anhydride content in the polymer for short reaction times. Increased temperature and maleic anhydride concentration had a positive effect on improving the incorporation of the succinyl anhydride moiety at the terminal site in polypropylene. Lower SnCl2 · 2H2O concentrations, likewise, improve the functionality of the product. The application of a second-order kinetic model to the measured succinyl anhydride results was not valid over the entire temperature range studied due to side reactions, particularly vinylidene isomerization, and homopolymerization of maleic anhydride. Ruthenium chloride has been examined as another possible catalyst candidate in the reaction and has been found to improve the level of anhydride incorporation in polypropylene compared to stannous chloride. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2371-2380, 1998
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    Nonhydrolytic synthesis and structural study of methoxyl-terminated polysiloxane D/Q resins (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2415-2425 
    Details
    ISSN: 0887-624X
    Keywords: polysiloxane ; resin ; nonhydrolytic condensation ; 29Si-NMR ; redistribution reactions ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Low-viscosity, methoxylated polysiloxane resins incorporating Me2SiO2/2 (D) and SiO4/2 (Q) units were prepared using nonhydrolytic condensation between Si - Cl and Si - OMe groups with the formation of MeCl, catalyzed by a Lewis acid. With the commonly used catalysts, condensation between two Si - OMe groups, with formation of Me2O, also took place to a large extent, hindering the control of the degree of condensation of the resins. Several catalysts were tested by monitoring the formation of MeCl and Me2O using sealed NMR tubes and 1H-NMR spectroscopy. The best compromise between reactivity and selectivity was obtained with ZrCl4. Resins with various compositions were prepared in the absence of solvent by condensation between Me2SiCl2 and Si(OMe)4 at 130°C, catalyzed by 1 mol % ZrCl4. They were characterized using viscosimetry, gas chromatography coupled with mass-spectrometry (GC-MS), and quantitative 29Si-NMR spectroscopy. The resins consisted of a complicated mixture of oligomers, linear or branched (n 〉 1) and cyclic (n 〉 3), with a high degree of D/Q bonding. The distribution of Si - OMe and Si - OSi bonds and the bonding between D and Q units were found to be nearly random. This was ascribed to the occurrence of Si - OSi/Si - OMe and Si - OSi/Si - OSi redistribution reactions that reached equilibrium during the synthesis. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2415-2425, 1998
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    Unusually facil cis to trans isomerization of a polypropiolate bearing a long alkyl chain polymerized using a [Rh(norbornadiene)Cl]2 catalyst: An ESR study (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2457-2461 
    Details
    ISSN: 0887-624X
    Keywords: polyalkylpropiolate ; Rh complex catalyst ; isomerization ; ESR ; soliton ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Alkylpropiolate having n-hexadecyl moiety in the ester group was stereospecifically polymerized with a [Rh(norbornadiene)Cl]2 complex catalyst in alcohol to give rise to cis-transoid polyacetylenes in high yields. The unusually facile cis to trans isomerization for the polymer was found to be induced when the polymer was warmed to even less than ca. 57°C. Under these conditions ESR spectra bearing hyperfine structures due to the radicals generated by the rotational scission in the cis-π bond were observed. This isomerization induced a large g value shift in the ESR spectra together with an increase of the radical concentration during the isomerization, indicating formation of planar conjugated trans sequences that stabilize mobile unpaired electrons as solitons. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2457-2461, 1998
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    Synthesis of a well-defined glycopolymer by atom transfer radical polymerization (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2473-2481 
    Details
    ISSN: 0887-624X
    Keywords: well-defined glycopolymer ; controlled/living radical polymerization ; atom transfer radical polymerization ; amphiphilic block copolymer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Controlled free radical polymerization of sugar-carrying methacrylate, 3-O-methacryloyl-1,2 : 5,6-di-O-isopropylidene-d-glucofuranose (MAIpGlc) was achieved by the atom transfer radical polymerization (ATRP) technique with an alkyl halide/copper-complex system in veratrole at 80°C. The time-conversion first-order plot was linear and the number-average molecular weight increased in direct proportion to the ratio of the monomer conversion to the initial initiator concentration, providing PMAIpGlc with a low polydispersity. The sequential addition of the two monomers styrene (S) and MAIpGlc afforded a block copolymer of the type PS-b-PMAIpGlc. The acidolysis of the homo- and block copolymers gave well-defined glucose-carrying water-soluble polymers PMAGlc and PS-b-PMAGlc, respectively. The amphiphilic PS-b-PMAGlc block copolymer exhibited a microdomain surface morphology with spherical PS domains in a PMAGlc matrix. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2473-2481, 1998
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    Preparation and properties of new soluble aromatic polyamides from 2,2′-bis(4-aminophenyl)biphenyl and aromatic dicarboxylic acids (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2029-2035 
    Details
    ISSN: 0887-624X
    Keywords: 2,2′-bis(4-aminophenyl)biphenyl ; aromatic polyamides ; solubility ; thermal behavior ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New biphenyl-2,2′-diyl-containing aromatic polyamides having a crank and twisted noncoplannar structure were synthesized in inherent viscosities of 0.39-1.42 dL/g by the low-temperature solution polycondensation of 2,2′-bis(4-aminophenyl)biphenyl, prepared in four steps starting from 2-aminobiphenyl, with various aromatic dicarboxylic acid chlorides. These polyamides were readily soluble in a variety of solvents including N,N-dimethylacetamide, N-methyl-2-pyrrolidone (NMP), m-cresol, and pyridine. Transparent, pale-yellow, and flexible films could be cast from the NMP solutions of the polyamides. The aromatic polyamides had glass transition temperatures in the range of 284-320°C, and began to lose weight around 400°C, with 10% weight loss being recorded at about 500°C in air. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2029-2035, 1998
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    Correlation of chemical structure and swelling behavior in N-alkylacrylamide hydrogels (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2095-2102 
    Details
    ISSN: 0887-624X
    Keywords: N-alkylacrylamide ; N-isopropylacrylamide ; hydrogel ; thermosensitive ; volume transition ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermoshrinking properties have been studied for the series of N-alkyl-acrylamide hydrogels (alkyl = methyl, ethyl, isopropyl, and n-propyl), which were prepared by free-radical copolymerization of the alkylacrylamide, sodium acrylate, and N,N′-methylenebis(acrylamide) (BIS) in aqueous solution. The reaction mixtures were prepared using the same nominal compositions in an effort to study the effect of the chemical structure of the alkyl substituent on the gel swelling behavior as a function of temperature. The alkyl group was found to have a pronounced effect on the features of gel swelling. Generally, larger alkyl chains produced dramatic decreases in gel transition temperature. In addition, a change in the nature of the swelling behavior from continuous to discontinuous was noted upon changing the alkyl group from ethyl to the two propyl derivatives. Discontinuous transitions were accompanied by hysteresis. The transition temperatures of the isomeric propyl derivatives were found to differ by 12°C, with n-propyl exhibiting the lower value. Additionally, a quantitative correlation was found between the gel transition temperatures and the water/octanol partition coefficients for appropriately chosen small molecule model compounds. The transition temperatures of other gels in the series, including the cyclopropyl derivative and the n-propyl/isopropyl copolymer gels (NIPA/NNPA), also fit this correlation. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2095-2102, 1998
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    Morphology control of organometallic domains in phase-separated poly(styrene-block-ferrocenyldimethylsilanes) (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2147-2150 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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    Palladium-catalyzed modification of poly(p-bromostyrene) with 4-(phenylamino)azobenzene. Optical properties of new azobenzene group-containing polystyrene (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2155-2160 
    Details
    ISSN: 0887-624X
    Keywords: palladium complex ; polymer reaction ; azobenzene ; cis-trans isomerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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    Syntheses and biological activities of α-methoxy-exo-3,6-epoxy-1,2,3,6-tetrahydrophthaloyl-5-fluorouracil and its polymers (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2177-2184 
    Details
    ISSN: 0887-624X
    Keywords: α-methoxy-exo-3,6-epoxy-1,2,3,6-tetrahydrophthaloyl-5-fluorouracil (METFU) ; poly(METFU-co-AA) ; poly(METFU-co-VAc) ; photopolymerization ; molecular weight ; in vitro cytotoxicity ; in vivo antitumor activity ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The new monomer, α-methoxy-exo-3,6-epoxy-1,2,3,6-tetrahydrophthaloyl-5-fluorouracil (METFU), was synthesized by the reaction of 5-fluorouracil (5-FU) and exo-3,6-epoxy-1,2,3,6-tetrahydrophthalic anhydride (ETA) in order to prepare polymers containing 5-FU moiety. Poly(α-methoxy-exo-3,6-epoxy-1,2,3,6-tetrahydrophthaloyl-5-fluorouracil) [poly(METFU)], poly(α-methoxy-exo-3,6-epoxy-1,2,3,6-tetrahydrophthaloyl-5-fluorouraci-co-acrylic acid) [poly(METFU-co-AA)], and poly(α-methoxy-exo-3,6-epoxy-1,2,3,6-tetrahydrophthaloyl-5-fluorouracil-co-vinyl acetate) [poly(METFU-co- VAc)] were synthesized by photopolymerizations using 2,2-dimethoxy-2-phenylacetophenone (DMP) as an initiator. The synthesized METFU and the polymers were identified by FTIR and 1H-NMR spectroscopies. The contents of METFU in poly(METFU-co-AA) and poly(METFU-co-VAc) determined by elemental analysis were 52 and 60 mol %, respectively. The average molecular weights and polydispersity indices determined with GPC were as follows: Mn = 9,400, Mw = 11,400 Mw/Mn = 1.21 for poly(METFU), Mn = 14,400, Mw = 26,800, Mw/Mn = 1.86 for poly(METFU-co-AA), and Mn = 23,100, Mw = 33,000, Mw/Mn = 1.43 for poly(METFU-co-VAc). The in vitro cytotoxicities of samples were evaluated with mouse mammary carcinoma (FM3A), mouse leukemia (P388), and human histiocytic lymphoma (U937) as cancer cell lines, and mouse liver cells (AC2F) as a normal cell line. The in vivo antitumor activities of synthesized polymers against mice bearing the sarcoma 180 tumor cell line were greater than those of 5-FU at concentrations of 0.8 and 80 mg/kg. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2177-2184, 1998
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    Transformation of the cationic growing center of poly(tetrahydrofuran) into an anionic one by bis(pentamethylcyclopentadienyl)samarium (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2209-2214 
    Details
    ISSN: 0887-624X
    Keywords: cationic polymerization ; anionic polymerization ; transformation ; samarium ; block copolymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Transformation of the cationic growing center of living poly(tetrahydrofuran) [poly(THF)] into an anionic one was achieved in high efficiency (62%) by the end-capping of living poly(THF) with potassium iodide followed by the reduction with bis(pentamethylcyclopentadienyl)samarium (Cp*2Sm), whereas the direct reduction with Cp*2Sm without the end-capping resulted in the formation of poly(THF) with pentamethylcyclopentadienyl group at the terminal. The increase in the molecular weight of poly(THF) after the reduction was observed, which indicates the presence of the dimerization of poly(THF) during the reduction. The polymerization of a variety of electrophilic monomers including δ-valerolactone, 2-oxo-1,3-dioxane, and alkyl methacrylates with the macroanion provided good yields of the corresponding block copolymers consisting of both cationically and anionically polymerizable monomers. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2209-2214, 1998
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    Synthesis and properties of new Si—H-containing polymers (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2275-2282 
    Details
    ISSN: 0887-624X
    Keywords: condensation polymerization ; preceramic ; dehydrocoupling ; hydrosilylation ; gelation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly[(methylsilylene)ethynylene] (1) and poly[2,5-thiophenediyl(methylsilylene)] (2) are prepared in good yields. Thermogravimetric analysis and differential scanning calorimetry indicate the Si—H group to increase the pyrolysis residue yields. Gelation was achieved from polymer 1 to get improved preceramic materials. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2275-2282, 1998
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    Synthesis and ferromagnetic properties of composites of a water-soluble polyaniline copolymer containing iron oxide (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2749-2755 
    Details
    ISSN: 0887-624X
    Keywords: polyaniline ; γ-Fe2O3 ; ferromagnetic properties ; nanometer materials ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Composites of water-soluble conducting polyaniline copolymers, poly(aniline-co-aminobenzenesulfonic acid) (PAOABSA), containing γ-Fe2O3magnetic particles with nanometer size, were synthesized by a chemical method. The ferromagnetic properties of the resulting PAOABSA composites were measured as a function of the pH value of the reaction solution, the sulfonated degree of the copolymer, and the concentration of FeCl2. The structure of the composites was characterized by means of elemental analysis, FTIR, XPS, and X-ray diffraction. It was found that increasing the pH value of the reaction solution and the concentration of FeCl2 is favorable for an enhancement of the saturated magnetization. As high as 33.2 emu/g of saturated magnetization for the PAOABSA composites was observed. No hysteresis loop (i.e. Hc = 0) was observed, which is independent of the preparation conditions. Structure characterizations show that iron oxide existing in the composite is mainly γ- Fe2O3, which is responsible for the ferromagnetic properties of the PAOABSA composites, whereas γ- Fe2O3 magnetic particles nanometer in size (∼85 nm) may be attributed to a lower coercive force (i.e. Hc = 0) of the composites. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2749-2755, 1998
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    Kinetic investigations on the photopolymerization of di- and tetrafunctional methacrylic monomers in polymeric matrices. ESR and calorimetric studies. II. Postpolymerization reactions (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2785-2791 
    Details
    ISSN: 0887-624X
    Keywords: postpolymerization reactions ; ESR ; polymeric matrices termination reactions ; H-transfer reactions ; kinetic constants ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction kinetics in the dark of photopolymerized mono- and dimethacrylates in a polymeric binder has been studied. Electron spin resonance spectroscopy (ESR) provided useful information regarding the nature of the radicals involved in postpolymerization reactions. Computer simulations were performed to study the decay of the propagating radicals by considering normal bimolecular termination and transfer reactions of the radicals to the binder. Differences were found in the termination reactions for mono- and difunctional monomers when they were photopolymerized in a solid medium. Absolute kinetic constants for H-transfer reaction with the binder, relative kinetic rate constants for radical-radical coupling, and average lifetimes for the radicals have been calculated. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2785-2791, 1998
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    Synthesis and characterization of 4-cyanobiphenyl-4′-yloxy-functionalized poly(7-oxanorbornene-5,6-exo-dicarboximide)s via ring opening metathesis polymerization (ROMP) (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2807-2821 
    Details
    ISSN: 0887-624X
    Keywords: ring opening metathesis polymerization (ROMP) ; Mitsunobu condensation ; side chain liquid crystal polymers (SCLCPs) ; 7-oxanorbornene-dicarboximide monomers ; structure-property relationships in SCLCPs ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N-[n-(4-cyanobiphenyl-4′-yloxy)alkyl]-7-oxanorbornene-5,6-exo-dicarboximide (CBON2-CBON8) with increasing number of methylene groups in the alkyl part (n = 2-8) were synthesized by Mitsunobu condensation between the appropriate alcohols (CBA2-CBA8) and 7-oxanorbornene-5,6-exo-dicarboximide (ON). The conditions for the ring opening metathesis polymerization of CBONn giving acceptable molecular weights and molecular distributions were established. Characterization of the resulting polymers (P2-P8) by 1H- and 13C-NMR has shown a high trans content. Differential scanning calorimetry and optical microscopy analysis have shown that the alcohols CBAn are thermotropic with some variations between the first and second heating-cooling cycles, the monomers CBONn melt with no evidence of any mesomorphic state, the polymers Pn show only the glass transition, and the glass transition temperature (Tg) decreases with increases in the spacer length. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2807-2821, 1998
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    Emulsion polymerization of styrene using an alkali-soluble random copolymer as polymeric emulsifier (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2865-2872 
    Details
    ISSN: 0887-624X
    Keywords: alkali-soluble random copolymer ; polymeric emulsifier ; aggregate ; hairy ASR layer ; rate of polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An alkali-soluble random copolymer (ASR), poly(styrene/α-methylstyrene/acrylic acid), was used as a polymeric emulsifier in the emulsion polymerization of styrene. The calorimetric technique was applied to study the kinetics of emulsion polymerization of styrene using ASR and a conventional ionic emulsifier, sodium dodecyl benzenesulfonate (SDBS). ASR could form aggregates like micelles, and the solubilization ability of the aggregates was dependent on the neutralization degree of ASR. The rate of polymerization in the ASR system was lower than that in the SDBS system. This result can be explained by the creation of a hairy ASR layer around the particle surface, which decreases the diffusion rate of free radicals through this region. Although a decrease in particle size was observed, the rate of polymerization decreased with increasing ASR concentration. The higher the concentration of ASR is, the thicker and denser ASR layer may be, and the more difficult it would therefore be for radicals to reach the particle through this layer of ASR. The rate of polymerization decreased with increasing the neutralization degree of ASR. The aggregates with high neutralization of ASR are less efficient in solubilizing the monomer and capturing initiator radicals than that of the lower neutralization degree, which leads to decrease in rate of polymerization. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2865-2872, 1998
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    Cationic polymerization of 1,3-dioxepane in the presence of 2,2-bis(hydroxymethyl)butanol (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2899-2903 
    Details
    ISSN: 0887-624X
    Keywords: cationic ring-opening polymerization ; poly(1,3-dioxepane) triol ; 2,2-bis(hydroxymethyl)butanol ; transacetalization ; activated monomer mechanism ; activated chain mechanism ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Cationic polymerization of 1,3-dioxepane (DOP) initiated by triflic acid was carried out in the presence of 2,2-bis(hydroxymethyl)butanol (BHMB). The structure and molecular weight of the products were characterized by GPC and NMR spectra. The results showed that molecular weight of the polyacetal obtained could be controlled by the initial mole ratio of DOP/BHMB. GPC showed that as the mole ratio of BHMB/DOP increased, the content of cyclic oligomers also increased. Proton, 13C and 2D HMQC-fg NMR demonstrated that no hydroxymethyl group of BHMB appeared as an end group. It was also illustrated by proton NMR that some BHMB units existed in cyclic oligomers. The mechanism of formation of cyclic oligomers was discussed. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2899-2903, 1998
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    Atom transfer radical polymerization of styrene initiated by polychloroalkanes and catalyzed by CuCl/2,2′-bipyridine: A kinetic and mechanistic study (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2933-2947 
    Details
    ISSN: 0887-624X
    Keywords: atom transfer radical polymerization ; styrene ; initiation ; polychloroalkanes ; redox telomerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of polychloroalkanes, known as telogen agents for redox telomerization, were used as initiators for atom transfer radical polymerization (ATRP) of styrene using the heterogeneous CuCl/2,2′-bipyridine catalyst. In copper-catalyzed redox telomerization, the reactivity of RCCl3-type telogens is strongly influenced by the nature of the R group. In ATRP, the 2,2′-bipyridine ligand levels the activity of the catalytic system in such a way that all 1,1,1-trichloroalkanes are efficient initiators in ATRP, whatever the R group. The nature of this substituent influences the overall rate of polymerization through both the number of active sites per chain and the [Cu (I)]/[Cu (II)] ratio. By the combining of several analytical techniques, it is proved that some polychloroalkanes such as CCl3CO2CH3, CCl3CF3, or CCl4 are bifunctional initiators. Finally, a general mechanism of initiation is proposed. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2933-2947, 1998
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    Synthesis and characterization of random hydrophilic/hydrophobic copolymers of styrene and D-lactose-O-vinylbenzylhydroxime (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2971-2978 
    Details
    ISSN: 0887-624X
    Keywords: styrene ; amphiphilic copolymer ; solution polymerization ; copolymerization ; solubility ; thermostability ; radical polymerization ; polymeric surfactant ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: D-Lactose-O-(vinylbenzyl)oxime (LVO), prepared from α-D-lactose and [O-(vinylbenzyl)oxy]amine (1) was copolymerized with styrene (ST) in dimethylsulfoxide (DMSO)-toluene (1 : 1, v/v) at 65°C using 2,2′-azobisisobutyronitrile (AIBN) as a free radical initiator. The polymerization was rapid when using AIBN as the initiator. The resultant copolymers were characterized by elemental analyses, infrared, viscometry, TGA, DSC, and 1H-NMR spectroscopy. The poly(ST-co-LVO) had an intrinsic viscosity in the range of 0.11-0.51 dL/g in DMSO at 30°C. The molecular weight was determined by gel permeation chromatography (GPC), and the molecular weight of the resulting polymers ranged from 2.11 × 104 to 6.53 × 107 with low polydispersities. The solubility of the copolymers with different monomer compositions in solvents of varied polarities was also studied. Incorporation of up to 65% (mol %) of lactose-based monomer onto polystyrene backbone led to a water-soluble polymer. Thermal behavior of the synthesized copolymers was evaluated by thermogravimetric analysis (TGA) and correlated very well with the polymer composition. Introduction of a pendant disaccharide compromised the thermal stability of the copolymer. The synthetic approach described in this report provides a route to prepare a novel disaccharide surfactant polymer with well-defined structures and hydrophilic/hydrophobic balances, by adjusting feed ratio of the lactose-based monomer (1) to styrene. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2971-2978, 1998
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    Synthesis and characterization of water-soluble conducting copolymer poly(aniline-co-o-aminobenzenesulfonic acid) (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 3013-3019 
    Details
    ISSN: 0887-624X
    Keywords: polyaniline ; water soluble ; degree of sulfonation ; copolymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The water-soluble conducting copolymer of poly(aniline-co-o-aminobenzenesulfonic acid) (PAOABSA) was synthesized directly from aniline and o-aminobenzenesulfonic acid and characterized by elemental analysis, FTIR, UV-Vis, X-ray powder diffraction, and XPS. The room-temperature conductivity of the copolymer can be changed by controlling the molar fraction of the starting materials, and its maximum conductivity at room temperature can reach 3.4 S/cm, which is comparable with polyaniline (PANI) synthesized by the standard method and sulfonated polyaniline (SPAN) having a high degree of sulfonation reported by Wei et al. It was found that the roomtemperature conductivity of the copolymer decreases with increase of the degree of sulfonation because of the introduction of the —SO-3 group reducing the conjugation of the polymer chain. On the other hand, its solubility in 1.0M NaOH solution increases with increase of the degree of sulfonation due to the —SO-3 group linking directly on the phenyl rings of the polymer chain. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 3013-3019, 1998
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    Ablation characteristics of silicone insulation (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 233-239 
    Details
    ISSN: 0887-624X
    Keywords: silicone rubber ; insulation ; ablation ; thermal decomposition ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ablation characteristics of silicone insulation were examined in an induced air combustion chamber and by thermogravimetric analysis. The rate of ablation increased with the combustion pressure. Although the flame temperature was less effective in increasing the ablation rate, the ablation rate below 1160 K was much smaller than expected. The decomposition kinetics of the silicone insulation was significantly altered at this temperature range. The stability of the char layer was much higher below approximately 1000 K. Since the lower ablation rate was obtained in higher mass flow rate condition, the heat input from the boundary layer to the insulation surface was decreased at this condition. The expended insulation consisted of a virgin zone, reaction zone, and char layer. These degraded materials were generated at relatively narrow temperature ranges. The char layer maintained a silicone backbone structure even though it experienced severe conditions. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 233-239, 1998
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    Pressure-induced cis to trans isomerization of aromatic polyacetylenes prepared using a Rh complex catalyst: A control of π-conjugation length (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 217-223 
    Details
    ISSN: 0887-624X
    Keywords: aromatic polyacetylene ; Rh complex catalyst ; cis-transoid ; pressure ; isomerization ; solitons ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This study reports that stereospecific polymerization of aromatic acetylenes, e.g., p-methoxyphenylacetylene (pMOPA) and p-ethoxyphenylacetylene (pEOPA)was successfully performed to give polyacetylene selectively bearing cis-transoid forms in high yield when a Rh complex catalyst, [Rh(norbornadiene)Cl]2 was used in the presence of triethylamine as the polymerization solvent together with a detailed characterization of the resulting polymers, before and after compression. Compression of these polymers induced a cis-trans isomerization at room temperature under vacuum even in the solid state. Based on data collected before and after compression it is estimated that the trans conjugated length, (C=C)n, produced as a result of the compression is n = 26 for PpMOPA and n = 40 for PpEOPA polymers, respectively. We further found that g values in the ESR spectra of the pristine polymer were shifted to higher magnetic field by compression, indicating that unpaired electrons called solitons are stabilized in the trans conjugation length as mobile electrons, although in the pristine polymers the unpaired electrons are stabilized in the less conjugated chain, showing large g value, suggesting a magnetic interaction between oxygen in the alkoxy group of phenyl moiety and unpaired electrons in the cis form. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 217-223, 1998
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    Electron photoejection and its application in studies of electron transfers (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. v 
    Details
    ISSN: 0887-624X
    Keywords: electron photoejection ; electron transfer ; radical anion disproportionation ; initiation ; anionic polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The principle of the electron photoejection technique is explained. This approach leads to the formation of transient spectra of unstable intermediates, allowing their recording and providing their extinction coefficients. Moreover, it permits determination of their electron affinities and the rates of their reactions, whether spontaneous or with some added substrates. Application of this technique to studies of disproportionation of radical anions has been most profitable. It led to the determination of the forward and backward rate constants of disproportionation of a variety of radical anions, and to discovery and quantification of some subtle features of these reactions. The electron photoejection technique provided the data characterizing the electron transfer initiation of anionic polymerization and clarified some of its features. Other opportunities provided by the electron photoejection in studies of electron transfer processes are suggested. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: v-xiii, 1998
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    Ethene-propene copolymerization with the MgCl2-supported dichlorobis(4,4,4-trifluoro-1-phenyl- 1,3-butanedionato)titanium catalyst activated by an ordinary trialkylaluminum (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2735-2740 
    Details
    ISSN: 0887-624X
    Keywords: Ti(BFA)2Cl2/MgCl2 catalyst (BFA = 4,4,4-trifluoro-1-phenyl-1,3-butanedione) ; activation by trialkylaluminum with or without diisopropyldimethoxysilane ; copolymerization of ethene with propene ; homogeneity of active species ; homogeneity of copolymers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The Ti(BFA)2Cl2/MgCl2-Al(C2H5)3 catalyst (BFA = 4,4,4-trifluoro-1-phenyl-1,3-butanedione) modified by DIPDMS (diisopropyldimethoxysilane), which had been proved to yield an extremely high isotactic polypropene in high selectivity, was tested for the copolymerization of ethene with propene. The analysis of resulting copolymers by CFC (cross fractionation chromatography) indicated the formation of a small quantity of ethene-rich copolymers as a byproduct, suggesting that the catalyst possesses not only Ti(III) species but a small portion of Ti(II) species. Whereas, the same catalyst without being modified by an external donor selectively yielded propene-rich random copolymers resulting from Ti(III) species in high yields. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2735-2740, 1998
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    Styrene-assisted free radical grafting of glycidyl methacrylate onto polyethylene in the melt (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2763-2774 
    Details
    ISSN: 0887-624X
    Keywords: free radical grafting ; glycidyl methacrylate ; polyethylene ; styrene ; reactive extrusion ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Glycidyl methacrylate (GMA) is a very useful monomer as it bears an epoxy group which is capable of reacting with various other functional groups. However, its melt free radical grafting reactivity onto a polymer backbone is low. In this study, we show that the use of styrene (St) as a comonomer greatly promotes both GMA's grafting yield and grafting rate onto polyethylene (PE). It is proposed that, in the presence of St, the dominant mechanism of the free radical grafting of GMA onto PE is that St reacts first with PE secondary macroradicals and the resulting styryl macroradicals then copolymerize with GMA leading to grafted GMA. We also show that the contribution of St is not related to an improved solubility of GMA in the molten PE. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2763-2774, 1998
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    The kinetics of diethylene glycol formation in the preparation of polyethylene terephthalate (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 3073-3080 
    Details
    ISSN: 0887-624X
    Keywords: direct esterification ; BHET ; EG ; DEG ; OH reactivity ; kinetics ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: For revealing diethylene glycol (DEG) formation in poly(ethylene terephthalate) (PET) synthesis, this research focused on finding the stage most critical for DEG formation. It is found that the esterification stage was the most critical stage for DEG formation during production of PET through the direct esterification process. In addition, the kinetics of the formation of DEG (ether bond), which is mainly produced from hydroxyl end groups of ethylene glycol (EG) and bis-hydroxyethyl terephthalate (BHET) oligomer, was investigated. The results show that the reactivity of BHET-OH functional group is greater than that of EG-OH functional group in the reaction to produce ether bonds. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 3073-3080, 1998
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    Synthesis and properties of widely conjugated polyacetylenes having anthryl and phenanthryl pendant groups (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 3131-3137 
    Details
    ISSN: 0887-624X
    Keywords: metathesis polymerization ; poly(arylacetylene) ; conjugated polymer ; tungsten catalyst ; absorption spectrum ; fluorescence spectrum ; thermal stability ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The metathesis polymerization of 1- and 2-ethynylanthracenes (1-EA and 2-EA) and 2- and 3-ethynylphenanthrenes (2-EP and 3-EP) in the presence of various WCl6-based catalysts produced widely conjugated soluble polymers with relatively high molecular weights. The highest weight-average molecular weights of poly(1-EA) and poly(2-EA) reached 61,000 and 26,000, respectively, when Ph4Sn was used as cocatalyst, while those of poly(2-EP) and poly(3-EP) reached 23,000 and 65,000, respectively, with Ph3Bi as cocatalyst. In contrast, MoCl5-based catalysts were hardly or not effective for these monomers. A large red-shifted peak was observed centering at 570 nm (the cutoff at 750 nm) in the absorption spectrum of poly(1-EA), while the red-shifted peaks were seen around 500 nm (the cutoffs near 700 nm) in the spectra of other polymers, indicating wide conjugations of the polymer chains. The configurational structures of all the polymers confirmed by DSC and 1H-NMR were trans structures. However, poly(1-EA) and poly(3-EP) appeared to consist partly of cis structures in their main chains. All of the present polymers showed relatively high thermal stability in air compared with poly(phenylacetylene). © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 3131-3137, 1998
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    Control of molecular weight of the polymers produced during the crystalline-state photopolymerization of diethyl cis,cis-muconate as studied by gel permeation chromatography and scanning electron micrography (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 3147-3155 
    Details
    ISSN: 0887-624X
    Keywords: topochemical polymerization ; radical polymerization ; molecular weight control ; solid-state photoreaction ; diethyl muconate ; microcrystals ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The molecular weight and its distribution of the resulting polymers were investigated during the crystalline-state photopolymerization of diethyl cis,cis-muconate (EMU). EMU crystals were prepared by several methods, recrystallization, milling, freeze drying, and precipitation, to obtain the crystals with various sizes of 10-6 to 10-2 m. After crystalline-state photopolymerization via a crystal-to-crystal process, polymer crystals were isolated and characterized by optical microphotography and scanning electron micrography. Molecular weight and its distribution were determined by gel permeation chromatography with 1,1,1,3,3,3-hexafluoro-2-propanol and by intrinsic viscosity in trifluoroacetic acid. It was revealed that the size of the EMU crystals depended on the method used for the crystal preparation, and that the molecular weight of the polymer decreased as the crystal size became small. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 3147-3155, 1998
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    Fractal notation for nearly-symmetrical dendrimers (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2979-2983 
    Details
    ISSN: 0887-624X
    Keywords: dendrimer ; nomenclature ; fractal ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Dendrimeric and related molecules that have the same atomic connectivity from exterior to core, P-C1-J1-C2- … Z (P peripheral group, J juncture, C connector, Z core) can be described completely by a highly compact fractal notation, which is of the general form PfJ1,J2 … (C1.C2 …)Z. In this paper, we show how to describe molecules that deviate slightly from the symmetry of a related parent molecule, by use of parenthetic expressions (iX), (dX), and (YrX) which designate atoms or molecular groups that are inserted, deleted, or replaced by other groups in the parent. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2979-2983, 1998
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    Polymerizations of olefins and diolefins catalyzed by monocyclopentadienyltitanium complexes containing a (dimethylamino)ethyl substituent and comparison with ansa-zirconocene systems (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 319-328 
    Details
    ISSN: 0887-624X
    Keywords: metallocenes ; Ziegler-Natta catalysis ; olefin polymerizations ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: {[2-(dimethylamino)ethyl]cyclopentadienyl}titanium trichloride (CpNTiCl3, 1) was activated with methylaluminoxane (MAO) to catalyze polymerizations of ethylene (E), propylene (P), ethylidene norbornene (ENB), vinylcyclohexene (VCH), and 1,4-hexadiene (HD). The dependence of homopolymerization activity (A) of 1/MAO on olefin concentration ([M]n) is n = 2.0 ± 0.5 for E and n = 1.8 ± 0.2 for P. The value of n is 2.4 ± 0.2 for CpTiCl3/MAO catalysis of ethylene polymerization; this system does not polymerize propylene. 1/MAO catalyzes HD polymerization at one-tenth of AH for 1-hexene, probably because of chelation effects in the HD case. The copolymerization of E and P has reactivity ratios of rE = 6.4 and rP = 0.29 at 20°C, and rErP = 1.9, which suggests 1/MAO may be a multisite catalyst. The copolymerization activity of CpTiCl3/MAO is 50 times smaller than that of CpNTiCl3/MAO. Terpolymerization of E/P/ENB has A of 105 g of polymer/(mol of Ti h), incorporates up to 14 mol % (∼ 40 wt %) of ENB, and high MW's of 1 to 3 × 105. All of these parameters are surprisingly insensitive to the ENB concentration. The E/P/VCH terpolymerization has comparable A value of (1.3 ± 0.3) × 105 g/(mol of Ti h). The incorporation of VCH in terpolymer increases with increasing [VCH]. Terpolymerization with HD occurs at about one-third of the A of either ENB or VCH; the product HD-EPDM is low in molecular weight and contains less than 4% of HD. These terpolymerization results are compared with those obtained previously for three zirconocene precursors: rac-ethylenebis(1-η5-indenyl)dichlorozirconium (6), rac-(dimethylsilylene)bis(1-η5-indenyl)dichlorozirconium (7), and ethylenebis(9-η5-fluorenyl)dichlorozirconium (8). The last compound is a particularly poor terpolymerization catalyst; it incorporates very little VCH or HD and no ENB at all. 7/MAO is a better catalyst for E/P/VCH terpolymerization, while 6/MAO is superior in E/P/HD terpolymerization. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 319-328, 1998
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    Note on the numerical solution of the Smith-Ewart equation of n modified for the isolated monomer droplets in a particular suspension polymerization (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 367-369 
    Details
    ISSN: 0887-624X
    Keywords: Smith-Ewart theory ; numerical solution ; suspension polymerization ; SPG membrane emulsification ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    Surface modification and adhesion characteristics of polycarbonate films after graft copolymerization (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 357-366 
    Details
    ISSN: 0887-624X
    Keywords: surface graft copolymerization ; adhesive-free adhesion ; polycarbonate ; XPS ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The surfaces of ozone-pretreated polycarbonate films were subjected to further modification by thermally induced graft copolymerization with acrylic acid (AAc), sodium salt of styrene sulfonic acid (NaSS), N,N-dimethylacrylamide (DMAA), N,N-(dimethylamino)ethyl methacrylate (DMAEMA) and 3-dimethyl(methacryloyl ethyl)-ammonium propanesulfonate (DMAPS) monomers. The structure and composition at the copolymer interface were studied by angle-resolved X-ray photoelectron spectroscopy (XPS). For polycarbonate films with a substantial amount of grafted polymer, the hydrophilic graft penetrates or becomes partially submerged beneath a thin surface layer of dense substrate chains. This microstructure was further supported by the water contact angle measurements. Adhesive-free adhesion studies revealed that the AAc, DMAA or DMAPS graft copolymerized polycarbonate film surface adhered strongly to another similarly modified surface (homo-interface) when brought into direct contact in the presence of water and subsequently dried. The development of the lap shear strength is dependent on the concentration of the surface graft, the microstructure of the grafted surface, the adhesion (drying) time, and the nature of the interfacial interaction. The simultaneous presence of chain entanglement and electrostatic interaction readily results in substantially enhanced adhesion strengths between two DMAPS graft copolymerized surfaces or between an AAc and a DMAA graft copolymerized surface (hetero-interface). XPS analyses of the delaminated surfaces suggest that failure occurred cohesively below the graft-substrate interface. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 357-366, 1998
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    Copolymerization of divinyl monomers with maleic and fumaric acid derivatives (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 371-378 
    Details
    ISSN: 0887-624X
    Keywords: copolymerization ; divinyl monomers ; diethyl fumarate ; maleic anhydride ; divinylbenzene ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The process of formation of reticular copolymer molecular structures produced in free radical copolymerization of divinyl monomers (divinyl ethers of diethylene glycol and hydroquinone, divinyl sulfide, p-divinylbenzene, etc.) with maleic and fumaric acid derivatives is studied. The basic factor that determines the features of molecular and network structures of copolymers is reactivity of the divinyl monomer in copolymerization with monovinyl monomer. The network of copolymers of maleic anhydride with the divinyl ether of hydroquinone is formed out of oligomer microgels. Divinyl sulfide in copolymerization with maleic acid is disposed to cyclocopolymerization; also crosslinking reactions occur. Formation of a network structure of copolymers of divinylbenzene with maleic and fumaric acid derivatives is shown to proceed via an alternating copolymerization mechanism. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 371-378, 1998
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    Low-temperature polycondensation of carboxylic acids and carbinols in heterogeneous media (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 341-356 
    Details
    ISSN: 0887-624X
    Keywords: aliphatic dicarboxylic acids ; aliphatic diols ; aliphatic hydroxy carboxylic acids ; low-temperature direct polyesterification ; narrow molecular weight distribution ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Aliphatic diols and dicarboxylic acids condense in hydrophobic solvents to form polyesters at 25-75°C when the solutions interface with an acidic hydrophilic phase. Certain aliphatic ω-hydroxy acids behave similarly. Rigorous removal of the by-produced water by distillation is unnecessary and examples are cited where polyesters are isolated in 85-90% yields having number-average molecular weights between 10,000-35,000. Polydispersity indices tend in many cases to be lower than expected for statistical step-growth polymerizations. Many of the side reactions encountered in high temperature polyesterifications, depending on the nature of the acidic phase, are absent or suppressed. While there are some limitations on the type of monomer, the mild conditions offer the possibility of forming polyesters with temperature sensitive structures directly from the corresponding carboxylic acids and carbinols. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 341-356, 1998
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    Oligomerization and cyclization of 1,2-ethanedithiol (EDT), HSCH2CH2SH, by selenium dioxide and iodine (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 379-390 
    Details
    ISSN: 0887-624X
    Keywords: selenium containing polymers ; poly(disulfide) polymers ; 1,2-ethanedithiol oxidation ; nuclear magnetic resonance ; Raman spectroscopy ; selenotrisulfide/disulfide chain and ring polymers ; mechanism of formation of selenotrisulfide polymers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of 1,2 ethanedithiol (EDT) with selenous acid in water or alcohol leads to selenopolysulfide chains or cycles, (C2H4SSeSC2H4SS)n, with randomly distributed —SSeS— and —SS— moieties. The reaction in water produces incompletely reacted material, which on recrystallization, gives an oligomer corresponding to 5 EDT units (pentamer) as confirmed by molecular mass determination, Se analysis, 1H- and 77Se-NMR spectroscopy. In both the pentamer and cyclic forms the incidence of neighboring —SSeS— moieties is higher than that expected statistically. The mechanism for the reaction of thiols with selenous acid provides some rationalization for this observation in as much as neighboring —SSeS— groups, or groups that will lead rapidly to neighboring —SSeS— groups are formed in general before —SS— links can be formed. The Raman spectrum of these products show typical strong SS, SeS, and CS stretching bands at 510, 370, and 730 cm-1. The high frequency of νCS is attributed to a preferred gauche conformation at the CS bonds. For comparison, polydisulfides were also prepared from EDT and iodine in methanol. These products consist of at least seven cyclic polymers ranging from the four-membered 1,2-dithietane to higher members. Heating above 100°C in chloroform for several hours gives a solution containing the four lowest molecular mass rings, which on standing for 24 h, precipitate highly insoluble material, which is probably chain or large-ring polymer. Molecular mass determination in camphor indicates that, like yellow sulphur, chain polymers are formed at the melting point of camphor (170°C). © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 379-390, 1998
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    Crosslinkable interpolymer complexes of novolac resin and poly(ethylene oxide) (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 401-411 
    Details
    ISSN: 0887-624X
    Keywords: novolac resin ; poly(ethylene oxide) ; interpolymer complexes ; crosslinkable ; polymer morphology ; thermal properties ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Crosslinkable interpolymer complexes of novolac resin and poly(ethylene oxide) (PEO) were prepared by mutual mixing ethanol solutions of novolac and PEO. Fourier transform infrared (FTIR) studies revealed that the driving force for the formation of novolac/PEO complex is hydrogen bonding interaction between the hydroxyl groups of novolac and the ether oxygens of PEO. The morphology and thermal properties of the complexes before and after curing were investigated by optical microscopy and differential scanning calorimetry (DSC). It was found that the uncured novolac/PEO complexes had a single composition-dependent glass transition temperature (Tg). The curing with 15 wt % hexamine (HMTA) (relative to novolac content) resulted in disappearing of Tg behaviour for both the neat novolac and the novolac-rich complexes, owing to less mobility of the novolac chain segments. The melting temperature (Tm) and crystallization rate of the HMTA-cured novolac/PEO complexes decreased with increasing novolac content, and no Tm was observed for the cured complexes with PEO content less than 50%. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 401-411, 1998
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    Effect of reaction conditions on synthesis and properties of multiarm star-branched polyisobutylenes (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 471-483 
    Details
    ISSN: 0887-624X
    Keywords: Multiarm star-branched polyisobutylenes ; reaction conditions ; synthesis ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of multiarm star-branched polyisobutylenes was synthesized from narrow polydispersity arms with molecular weights ranging from 12,000 to 60,000 g/mol, via living carbocationic polymerization using the cumyl chloride/TiCl4/pyridine initiating system and divinylbenzene (DVB) as core-forming comonomer. The effect on star development of arm molecular weight, temperature, solvent composition, and DVB concentration was studied. The rate of star formation and the weight-average number of arms per star polymer, N̄w, were found to scale inversely with arm molecular weight; N̄w = 60 was attained for 13,100 g/mol arms, but N̄w = 2.5 for 60,000 g/mol arms. It was established that star formation was much faster at -80°C compared to 23°C, regardless of solvent composition. For hexane : methyl chloride (MeCl) solvent compositions containing from 40 to 60 vol % MeCl, star-star coupling was observed at -80°C, but not at 23°C, even after 312 h; for the most polar 40 : 60 hexane : MeCl composition, star-star coupling was so extensive at -80°C that gelation was observed after only 44 h. The rate of star formation was found to be substantially higher in 60 : 40 hexane : MeCl compared to 60 : 40 hexane : methylene chloride (MeCl2). Some reactions containing MeCl were immediately warmed to 23°C after DVB addition, and the MeCl thus volatilized was replaced with either MeCl2 or hexane for the duration of the star-forming reaction. Slightly higher rates were consistently observed when MeCl2 was the replacement solvent. The strong influence of initial MeCl content on rate of star formation was found to persist throughout the star-forming reaction, even when the solvent was immediately converted to 100% hexane. The fraction of arms that remained unlinked into stars was found to be higher at the higher temperature and at lower solvent polarity. Regardless of solvent or temperature, the residual arm fraction was approximately the same at a given stage of star development as measured by the average number of arms per star. One star sample was produced with the UV-transparent 2-chloro-2,4,4-trimethylpentane initiator; analysis showed that the residual arm fraction had approximately the same UV absorbance as the star fraction, indicating efficient crossover to DVB and the potential for approximately quantitative arm incorporation given sufficient time. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 471-483, 1998
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    Poly(arylene ether)s and poly(arylene thioether)s containing the 1,2-dihydro-4-phenyl(2H)- phthalazinone moiety (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 455-460 
    Details
    ISSN: 0887-624X
    Keywords: poly(arylene ether)s ; poly(arylene thioether)s ; S-(N,N′-dimethylcarbamate) ; phthalazinone ; one-pot polymerization ; thermal stability ; heterocyclic ring ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of new high molecular weight poly(arylene ether)s containing the 1,2-dihydro-4-phenyl(2H)phthalazinone moiety have been synthesized. The inherent viscosities of these polymers are in the range of 0.33-0.64 dL/g. They are amorphous and readily soluble in chloroform, DMF, and DMAc. The glass transition temperatures of the polymers range from 241 to 320°C and the 5% weight loss temperatures in nitrogen atmosphere range from 473 to 517°C. The hydroxy group in the monomer 1,2-dihydro-4-(4-hydroxyphenyl)(2H)phthalazin-1-one has been selectively transformed into the N,N′-dimethylthiocarbamate group, which was then rearranged to give the S-(N,N′-dimethylcarbamate) group via the Newman-Kwart rearrangement reaction. A series of poly(arylene thioether)s containing the 1,2-dihydro-4-phenyl(2H)phthalazinone moiety have also been synthesized via two types of reactions, a N—C coupling reaction and a one-pot reaction between the S-(N,N′-dimethylcarbamate) and activated dihalo compounds, in diphenyl sulfone in the presence of a cesium carbonate and calcium carbonate mixture. These poly(arylene thioether)s also have high glass transition temperatures (ranging from 217-303°C) and high thermal stabilities. Compared with their poly(ether) analogs, the poly(arylene thioether)s have glass transition temperatures several degrees lower, which is attributed to the more flexible C—S—C bonds. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 455-460, 1998
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    Oxyethylene copolymers with chloromethyl and (alkylthio)methyl or (alkylsulfonyl)methyl side groups: Syntheses and Tg/composition relationships (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 495-504 
    Details
    ISSN: 0887-624X
    Keywords: copolymer ; glass transition temperature ; Fox equation ; sulfone ; thioether ; oxyethylene ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New classes of copolymers, poly[oxy(chloromethyl)ethylene]/poly[oxy-((alkylthio)methyl)ethylene] copolymers (CE-ATEs), poly[oxy((alkylthio)methyl)-ethylene]s (ATEs), poly[oxy(chloromethyl)ethylene]/poly[oxy((alkylsulfonyl)meth-yl)ethylene] copolymers (CE-ASEs), and poly[oxy((alkylsulfonyl)methyl)ethylene]s (ASEs) have been made for the first time. The thioether-containing polymers (CE-ATEs and ATEs) were synthesized by reacting poly[oxy(chloromethyl)ethylene] (CE, poly(epichlorohydrin)) with different amounts of sodium alkanethiolates. The sulfone-containing polymers (CE-ASEs and ASEs) were synthesized by oxidizing the CE-ATEs and ATEs using m-chloroperoxybenzoic acid. The Fox equation, a linear relationship, fit the Tg/composition data for most CE-ATEs. The Tg's of the CE-ASEs showed positive deviations from those calculated using the Fox equation. The Johnston equation, in which steric and/or polar interactions between dissimilar monomeric units are considered by using TgAB (the Tg of the AB or BA dyad), fit the Tg/composition data for all copolymers in this study. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 495-504, 1998
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    Polymerization by oxidative coupling: Discovery and commercialization of PPO® and Noryl® resins (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 505-517 
    Details
    ISSN: 0887-624X
    Keywords: oxidative coupling ; polymerization ; PPO® ; Noryl® ; discovery ; commercialization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The discovery of oxidative polymerization and the commercial development of PPO® and Noryl® resins is described. The scope of the oxidative polymerization reaction is discussed. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 505-517, 1998
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    Preparation and characterization of thermoresponsive isopropylacrylamide-hydroxyethylmethacrylate copolymer gels (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 527-541 
    Details
    ISSN: 0887-624X
    Keywords: isopropylacrylamide ; hydroxyethylmethacrylate ; thermoresponsive gel ; stimuli-responsive polymer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A random copolymer of N-isopropylacrylamide and 2-hydroxyethylmeth-acrylate, poly(NIPAM-co-HEMA), having thermoresponsive character was prepared bya redox copolymerization method. Poly(ethylene glycol), PEG 4000 was included in the copolymerization recipe to increase the thermoresponsivity of copolymeric structure. Poly(NIPAM-co-HEMA) copolymer gels having more elastic character and higher mechanical strength relative to poly(NIPAM) gel could be achieved by the proposed copolymerization procedure. The equilibrium and dynamic response against the temperature were investigated for the gel matrices produced by changing the initial NIPAM/HEMA mol ratio and PEG 4000 concentration in the copolymerization mixture. The effective diffusion coefficient of water within the gel matrix was estimated for either swollen or shrunken states by applying an unsteady-state diffusion model on the dynamic swelling and shrinking behaviors of gel matrix prepared in the cylindrical form. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 527-541, 1998
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    Synthesis and characterization of interpenetrating polymer networks for nonlinear optics (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 553-561 
    Details
    ISSN: 0887-624X
    Keywords: interpenetrating networks ; nonlinear optics ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two-component simultaneous interpenetrating networks (IPN) of thepoly(4′-[[2-(methylacryloxy)ethyl]ethylamino]-4-nitroazobenzene-co-methyl meth-acrylate) (PDR1MA-co-MMA)/poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) system, the PDR1MA/PPO system and 4′-[[2-(acetoxy)ethyl]ethylamino]-4-nitroazo benzene (ACDR1) doped MMA/PPO system were synthesized and characterized. As studied by differential scanning calorimetry (DSC) the full IPNs of the PDR1MA-co-MMA/PPO system and the PDR1MA/PPO system showed a single Tg varying with the PPO composition. A single-phase morphology of the full IPNs was also indicated by scanning electron microscopy (SEM). Transparent films were cast onto clean microscopic glass slides and poled at 190°C for 1 h. The UV-VIS absorption spectra of the three IPN systems before and after curing and corona poling showed a shift in the maximum absorption due to the induced alignment of the nonlinear optical chromophores in the IPN systems. The absorption intensity of the full IPNs remained same after heating at 120°C for 72 h, indicating that the electric field-induced alignment is stable in the full IPN materials. Preliminary second harmonic generation (SHG) data on these IPNs are presented. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 553-561, 1998
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    Radical polymerization of ortho-(1,3-dioxolan-2-yl)phenyl ethyl fumarate involving intramolecular hydrogen abstraction and ring opening of cyclic acetal (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 563-572 
    Details
    ISSN: 0887-624X
    Keywords: radical polymerization ; ortho-(1,3-dioxolan-2-yl)phenyl ethyl fumarate ; hydrogen abstraction ; cyclic acetal ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of o-(1,3-dioxolan-2-yl)phenyl ethyl fumarate (DOPEF) initiated with dimethyl 2,2′-azobisiso-butyrate (MAIB) was studied kinetically in benzene. The polymerization rate (Rp) at 60°C was given by Rp = k [MAIB]0.76 [DOPEF]0.71. The overall activation energy of polymerization was calculated to be 98.3 kJ/mol. The number-average molecular weight of resulting poly(DOPEF) was in the range of 1000-3100. 1H- and 13C-NMR spectra of resulting polymers revealed that the radical polymerization of DOPEF proceeds in a complicated manner involving vinyl addition, intramolecular hydrogen abstraction, and further ring opening of the cyclic acetal at higher temperatures. From the copolymerization of DOPEF (M1) and styrene (St) (M2) at 60°C, the monomer reactivity ratios were obtained to be r1 = 0.02 and r2 = 0.20, the values of which are similar to those of the copolymerization of ethyl o-formylphenyl fumarate and St. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 563-572, 1998
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    Polymerization of ethylene using high-activity Ziegler-type catalysts: Active center determination (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 573-585 
    Details
    ISSN: 0887-624X
    Keywords: polymerization ; Ziegler-Natta ; catalysis ; active centers ; ethylene ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The concentration of active centers of a high-activity magnesium chloride-supported Ziegler-Natta catalyst has been determined using three different methods. The initial active center concentration has been determined by quenching the reaction slurry with MeOT. To determine the concentration of the propagation species along the course of the polymerization the radio-tagging agent, 14CO, and the tagging agent, CS2, were used. CS2, was also investigated as a tagging agent of the growing chains, in a metallocene catalyst system. The results obtained were compared to obtain some insight about the reliability of each method and the kind of information each method can provide. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 573-585, 1998
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    Synthesis, hydrophilicity, and oxygen permeability of poly[(trimethylsilyl)propyne]-gr-poly(N,N-dimethylacrylamide) (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 603-610 
    Details
    ISSN: 0887-624X
    Keywords: poly[(trimethylsilyl)propyne] ; poly(N,N-dimethylacrylamide) ; graft copolymer ; oxygen permeability ; hydrophilicity ; water contact angle ; contact lens ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N,N-dimethylacrylamide (DMAA) was graft copolymerized on poly[(trimethylsilyl)propyne] (PTMSP) by single electron reduction of PTMSP with potassium naphthalenide (K-Naph), followed by anion polymerization of DMAA from the carbanion formed in the reduction. A hard and practically non-water-swelling PTMSP-gr-poly(DMAA) was obtained under the conditions using controlled amount of K-Naph and DMAA. The graft copolymer was characterized with regard to structure, number-averaged molecular weight, and the amount of grafting poly(DMAA) determined by the relative absorbance of the IR absorption band assigned to the C=O and SiC—H functionalities (AC=O/ASiC—H). The oxygen permeability and water contact angle (θ) of the graft copolymer were evaluated while varying the amount of grafting poly(DMAA). The graft copolymer proved to be highly oxygen permeable (165 Barrers) and hydrophilic (θ = 27°). Its transparency was also elucidated with UV-vis spectra. This graft copolymer was proposed as a promising candidate for use as a hard contact lens material. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 603-610, 1998
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    Polymers from multifunctional isocyanates 14. Alternating copolymers from isocyanato alkenes: Copolymerization of 2-propenyl isocyanate with trimethylsilyl methacrylate as electron acceptor monomer (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 611-616 
    Details
    ISSN: 0887-624X
    Keywords: alternating copolymerization ; free radical ; isopropenylisocyanate ; trimethylsilyl methacrylate ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The copolymerization of 2-propenyl isocyanate (1) with trimethylsilyl methacrylate (2) has been investigated. 1 is an electron donor monomer with little tendency to undergo homopolymerization, while 2 is an electron acceptor monomer, capable of free radical homopolymerization. Polymerization to low conversion in benzene gave copolymers with preferential incorporation of 2 and a tendency towards alternating copolymers with increasing amounts of 1 in the feed (1 : 1.13 with a 9 : 1 feed ratio of monomers 1 : 2). The glass transition temperatures of the amorphous polymers are in the range from 100-70°C, with a Tg of poly(trimethylsilyl methacrylate) being 135°C. Desilylation occurs in the presence of water, causing an exothermal reaction above the glass transition temperature probably with formation of amides, a reaction that can be used for crosslinking. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 611-616, 1998
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    In situ FTIR investigation of MMA plasmas, plasma-polymerized films, and reaction mechanisms (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 587-602 
    Details
    ISSN: 0887-624X
    Keywords: plasma polymerization ; methyl methacrylate ; in situ FTIR/ATR diagnostic ; in situ FTIR plasma diagnostic ; analysis of variance ; regression analysis ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Methyl methacrylate (MMA) plasmas and plasma-polymerized methyl methacrylate (PPMMA) films were studied in situ with FTIR and FTIR/ATR (attenuated total reflection) in an r.f. capacitively coupled glow discharge. A statistically designed experiment was conducted by varying the r.f. power, process pressure, and MMA flow rate. MMA plasma fragments were identified from the gas-phase FTIR measurements. They include the intermediate species such as dimethylketene, formaldehyde, allene, and propene; small hydrocarbons such as acetylene, methane, and ethylene; and oxygenates such as carbon dioxide, carbon monoxide, and methanol. Statistical analysis techniques (correlation analysis, analysis of variance and regression analysis) were used on both gas and film data. Gas-phase reaction mechanisms are proposed, and the relationship between the gas and film data is investigated to understand the film deposition chemistry. The deposition rate is positively correlated to the relative concentrations of MMA fragments which are identified as the major film precursors in the deposition process. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 587-602, 1998
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    ABC triblock polymethacrylates: Group transfer polymerization synthesis of the ABC, ACB, and BAC topological isomers and solution characterization (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 617-631 
    Details
    ISSN: 0887-624X
    Keywords: group transfer polymerization ; methyl methacrylate ; (dimethylamino)-ethyl methacrylate ; tetrahydropyranyl methacrylate ; methacrylic acid ; ABC triblock copolymers ; polymethacrylates ; polyampholytes ; block sequence ; water-soluble copolymers ; micelles ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: ABC triblock copolymers of methyl methacrylate (MMA), (dimethylamino)-ethyl methacrylate (DMAEMA), and tetrahydropyranyl methacrylate (THPMA) consisting of 12 units of each type of monomer were synthesized by group transfer polymerization (GTP). These were the three topological isomers with differentblock sequences: DMAEMA12-THPMA12-MMA12, DMAEMA12-MMA12-THPMA12, and THPMA12-DMAEMA12-MMA12. The molecular weights and molecular weight distributions of the copolymers were determined by gel permeation chromatography (GPC) in tetrahydrofuran, and their number-average degrees of polymerization and copolymer compositions were calculated by proton nuclear magnetic resonance spectroscopy (1H-NMR). These molecular weights and degrees of polymerization corresponded closely to the values expected from the monomer/initiator ratios. The polydispersities were low as expected for GTP, and ranged from 1.09 to 1.25. The three triblocks were chemically modified by converting the THPMA units to methacrylic acid (MAA) units either by thermolysis or acid hydrolysis. The resulting ABC triblock poly-ampholytes were characterized by 1H-NMR spectroscopy and hydrogen ion titration. Aqueous GPC studies in 1.0M NaCl at pH 8.5 showed that the triblock copolymers form micelles whose size depends on their block sequence. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 617-631, 1998
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    Polymerization of styrene with nickel complex/methylaluminoxane catalytic systems (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2119-2126 
    Details
    ISSN: 0887-624X
    Keywords: stereospecific polymerization ; isotactic polystyrene ; nickel catalysts ; methylaluminoxane ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymerization of styrene using catalytic systems based on nickel derivatives and methylaluminoxane (MAO) was studied. Among tested catalysts, nickel bis(acetylacetonate) and nickel dichloride show the maximum activity. Bis(phosphine)nickel dichlorides exhibit lower activity, depending on the nature of the phosphine ligand. Polymer yields decrease by lowering the catalyst concentration, by increasing the reaction temperature, or by carrying out the polymerization in a polar donor solvent. Weight average molecular weight of most of the prepared polystyrenes ranges from 9000 to 25,000, with polydispersity indexes of 1.6-3.8. However, polystyrene prepared in dioxane solvent exhibits a small fraction of very high molecular weight (about 140,000). From NMR analysis, the products seem generally to be constituted of two polymers with different steric microstructure: atactic polystyrene and partially isotactic polystyrene (ca. 75-85% meso diads). Catalytic site specificity is correlated with the type of nickel ligand, while the effect of reaction temperature is less defined. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2119-2126, 1998
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    Gel formation in cationic polymerization of divinyl ethers. I. 1,4-Bis(2-vinyloxyethoxy)benzene (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 675-683 
    Details
    ISSN: 0887-624X
    Keywords: cationic polymerization ; vinyl ether ; divinyl ether ; crosslinking ; gelation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymerization of 1,4-bis(2-vinyloxyethoxy)benzene (CH2=C—O—CH2—CH2—O—C6H4—O—CH2CH2—O—C=CH2; 1) was investigated in CH2Cl2 at 0°C with the use of a variety of cationic initiators. SnCl4, SnBr4, AlEtCl2, and BF3OEt2 (strong Lewis acids) and CF3SO3H (a strong protonic acid) yielded crosslinked insoluble polymers immediately after the polymerizations were initiated. The binary initiating systems such as HCl/ZnCl2 and (C6H5O)2P(O)OH/ZnCl2 also produced insoluble poly(1)s. At the low initial concentration of ZnCl2, however, the (C6H5O)2P(O)OH/ZnCl2 system gave the soluble polymers quantitatively, and gelation occurred only when the reaction mixture was stored for a long time after complete consumption of the monomer. The content of the unreacted pendant vinyl ether groups of the soluble polymers decreased with monomer conversion, and almost all the pendant vinyl ether groups were consumed in the soluble polymer obtained at 100% monomer conversion; this may be ascribed to frequent occurrence of intramolecular crosslinking. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 675-683, 1998
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    Peroxide induced crosslinking and degradation of polyvinyl chloride (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 851-860 
    Details
    ISSN: 0887-624X
    Keywords: polyvinyl chloride ; peroxide modification ; crosslinking ; degradation ; electron spin resonance ; kinetics ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Peroxide induced crosslinking and degradation of polyvinyl chloride (PVC) were experimentally investigated using an on-line electron spin resonance (ESR) spectroscopy technique. The reaction variables included temperature, peroxide type and concentration. A single line ESR spectrum was observed with its peak-to-peak width decreasing during the reaction. The mechanism involved in the reaction was elucidated based on the radical information. The radical concentration versus reaction time profile exhibited two distinct regions: the chemically initiated reaction continued by the thermal initiation. The addition of peroxide induced and significantly enhanced the thermal initiated crosslinking and degradation. The radical concentration data coupled with the extent of dehydrochlorination gave an estimate of the rate constant of polyene propagation. A significant decrease of the rate constant was observed during the reaction. The gel content and swelling ratio were also measured to provide additional information to the reaction process. The initial gelation rate increased with the increase of temperature and/or peroxide concentration. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 851-860, 1998
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    BF3·OEt2-initiated polymerization of 2-methylene-1,3-dioxepanes (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 873-881 
    Details
    ISSN: 0887-624X
    Keywords: 2-methylene-1,3-dioxepane ; 4,7-dimethyl-2-methylene-1,3-dioxepane ; cyclic ketene acetal ; cationic polymerization ; ring-opening polymerization ; ring-retained polymerization ; copolymerization ; boron trifluoride etherate ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: BF3·OEt2-initiated polymerizations of 2-methylene-1,3-dioxepane gave polymers composed of both ring-retained and ring-opened structures. The ring-opening content increased with an increase in polymerization temperature. Poly(4,7-dimethyl-2-methylene-1,3-dioxepane) propagated slower during BF3·OEt2-initiated polymerization and had a lower ring-opened content than poly(2-methylene-1,3-dioxepane). The type of acid initiator used also affected the amount of ring opening observed. Stronger acids gave less ring opening. Attempted BF3·OEt2-initiated copolymerizations of these seven-membered ring cyclic ketene acetals with isobutyl vinyl ether at room temperature resulted in formation of the two homopolymers. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 873-881, 1998
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    Synthesis and properties of polyamidines (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 929-938 
    Details
    ISSN: 0887-624X
    Keywords: polyamidines ; chain conformation ; hydrogen bonds ; prototropic tautomerism ; thermal stability ; hydrolytic stability ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymers with amidine groups —NH—CR=N— in the main chain were prepared by acid catalysed melt polycondensation of 4,4′-diaminodiphenyl methane (DAPM) with various orthoesters. The resulting polyamidines were characterized by 1H-, 13C- and 15N-NMR spectroscopy, differential scanning calorimetry (DSC), thermogravimetry (TGA) and wide angle x-ray scattering (WAXS) measurements. The properties of the polyamidines are strongly determined by the substituent R on the amidine group. Some peculiarities of the polyformamidine (R=H) could be attributed to the conformation of the amidine group. Glass transition temperatures varied from 106 to 161°C depending on the substituent R. All polyamidines possessed good thermal stability up to 370°C and, with exception of the polyformamidine, good solubility in common solvents. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 929-938, 1998
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    Synthesis of a novel highly conjugated conducting polymer (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 949-953 
    Details
    ISSN: 0887-624X
    Keywords: conjugated polyacetylene ; acetylene derivative ; poly(HPB) ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The new conjugated polyacetylene derivative dehydrated poly(4-hydroxy-4-phenyl-1-butyne) [dehydrated poly(HPB)] was synthesized from poly(4-hydroxy-4-phenyl-1-butyne) [poly(HPB)], which was obtained by the polymerization of 4-hydroxy-4-phenyl-1-butyne. The resulting dehydrated poly(HPB) was soluble in common organic solvents. The dehydrated poly(HPB) was found to have extended conjugated polyene structure. The dehydrated poly(HPB) was thermally stable up to 300°C. The electrical conductivity of I2-doped dehydrated poly(HPB) was 10-2 S cm-1. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 949-953, 1998
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    Effect of substituents on the curing of liquid crystalline epoxy resin (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 911-917 
    Details
    ISSN: 0887-624X
    Keywords: liquid crystalline epoxy resin ; substitution ; curing ; network ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of an aromatic ester based liquid crystalline epoxy resin (LCE) with a substituent in the mesogenic central group is described. Chlorine and methyl groups were introduced as substituents. The curing behaviors of three epoxy resins were investigated using diaminodiphenyl ester as the curing agent. The curing rate and heat of curing of LCE were measured with dynamic and isothermal DSC. The chlorine substituent accelerated the curing of LCE, while the methyl substituent decelerated the curing of LCE. The heat of curing of substituted LCE was diminished compared to LCE with no substituent. Glass transition temperature and elastic modulus of LCE decreased with increasing the size of the substituent. Three liquid crystalline epoxy resins based on aromatic ester mesogenic groups formed a liquid crystalline phase after curing, and the liquid crystalline phase was stable up to the decomposition temperature. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 911-917, 1998
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    New poly(amide-imide) syntheses. XXI. Synthesis and properties of aromatic poly(amide-imide)s based on 2,6-bis(4-trimellitimidophenoxy)naphthalene and aromatic diamines (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 919-927 
    Details
    ISSN: 0887-624X
    Keywords: poly(amide-imide)s ; direct polycondensation ; 2,6-bis(4-aminophenoxy)naphthalene ; 2,6-bis(4-trimellitimidophenoxy)naphthalene ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A novel polymer-forming diimide-diacid, 2,6-bis(4-trimellitimidophenoxy)naphthalene, was prepared by the condensation reaction of 2,6-bis(4-aminophenoxy)naphthalene with trimellitic anhydride (TMA). A series of novel aromatic poly(amide-imide)s containing 2,6-bis(phenoxy)naphthalene units were prepared by the direct polycondensation of the diimide-diacid with various aromatic diamines using triphenyl phosphite (TPP) in N-methyl-2-pyrrolidone (NMP)/pyridine solution containing dissolved calcium chloride. Thirteen of the obtained polymers had inherent viscosities above 1.01 dL/g and up to 2.30 dL/g. Most of polymers were soluble in polar solvents such as DMAc and could be cast from their DMAc solutions into transparent, flexible, and tough films. These films had tensile strengths of 79-117 MPa, elongation-at-break of 7-61%, and initial moduli of 2.2-3.0 GPa. The wide-angle X-ray diffraction revealed that some polymers are partially crystalline. The glass transition temperatures of some polymers could be determined with the help of differential scanning calorimetry (DSC) traces, which were recorded in the range 232-300°C. All the poly(amide-imide)s exhibited no appreciable decomposition below 450°C, and their 10% weight loss temperatures were recorded in the range 511-577°C in nitrogen and 497-601°C in air. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 919-927, 1998
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    Preparation and properties of processable polyimides having bulky pendent ether groups (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 971-978 
    Details
    ISSN: 0887-624X
    Keywords: processable polyimide ; bulky pendent ether groups ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of aromatic diamines containing pendent methoxy, phenoxy, and biphenoxy moieties were synthesized. By the reaction of diamines with 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA), several kinds of polyimides having bulky pendent ether groups were synthesized. Thermal properties and processability such as melt processability and solubility in organic solvents of obtained polyimides were investigated by focusing on the chemical structures of their repeating structure units. It was found that the thermal stability and melt processability of the polyimides did not strongly depend on the existence of bulky pendent phenoxy and biphenoxy moieties. Their solubility in organic solvents, however, was improved by introducing the bulky pendent ether groups such as methoxy, phenoxy, and biphenoxy moieties into their repeating structure units. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 971-978, 1998
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    A new direct preparation of electroconductive polyimide/carbon black composite via polycondensation of nylon-salt-type monomer/carbon black mixture (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1031-1034 
    Details
    ISSN: 0887-624X
    Keywords: electroconductive polymer ; polyimide-carbon black composite ; direct polycondensation ; salt monomer method ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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    Deposition conditions influence the postdeposition oxidation of methyl methacrylate plasma polymer films (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 985-1000 
    Details
    ISSN: 0887-624X
    Keywords: plasma polymers ; methyl methacrylate ; oxidation ; long-term stability ; XPS ; FTIR ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Plasma polymer films were deposited from methyl methacrylate (MMA) vapor under various plasma conditions and XPS and FTIR used to study the changes to the compositions of the films as they were stored in air for longer than 1 year. The plasma power input per monomer mass unit (W/FM) markedly affected the composition of the freshly deposited MMA plasma polymers. A low value of W/FM led to a high degree of retention of the original monomer structure, whereas a high value of W/FM resulted in substantial monomer fragmentation and the formation of a partially unsaturated material considerably different to conventional PMMA. As the MMA plasma coatings were stored in ambient air after fabrication, all showed spontaneous oxidative changes to their composition, but the extents and reaction products differed substantially. Deposition at low W/FM led to moderate oxidative changes, whereas high power led to a pronounced increase in the oxygen content over time and resulted in a wide range of carbon-oxygen functionalities in the aged material. As the initial compositions/plasma deposition conditions thus influenced the oxidative postdeposition reactions, MMA plasma polymers deposited under different conditions not only varied in their initial composition but then became even more diverse as they aged. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 985-1000, 1998
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    Molecular weight distribution of crosslinked polymers produced in emulsion (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1127-1156 
    Details
    ISSN: 0887-624X
    Keywords: emulsion polymerization ; crosslinking and long-chain branching ; molecular weight distribution ; compartmentalization ; gel formation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A kinetic model for evaluating the chain length distribution of a branched polymer produced in emulsion was developed. Chain branching occurring through any intermolecular mechanism is considered, namely, crosslinking, chain transfer to polymer and propagation to terminal double bond. The model accounts for active chain compartmentalization and, when coupled to a model able to describe the evolution of the polymerization system, allows evaluation of the cumulative properties of the produced polymer both in the pregel and postgel phases. The numerical difficulties related to the description of a rather wide polymer chain population and of gel formation are overcome by using the ‘numerical fractionation’ technique. A parametric analysis of both instantaneous and cumulative properties is reported and discussed, with special attention to the role of radical compartmentalization in determining the molecular weight properties of a polymer produced in emulsion. Significant differences with the molecular weights computed using models developed for homogeneous (non compartmentalized) systems have been found. A comparison with the predictions of Flory's statistical theory is also reported in terms of gel point and gel weight fraction. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1127-1156, 1998
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    Controlling molecular weight distributions of polyethylene by combining soluble metallocene/MAO catalysts (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 831-840 
    Details
    ISSN: 0887-624X
    Keywords: molecular weight distribution ; polyethylene ; soluble metallocene/MAO catalysts ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A critical look at the possibility of controlling the molecular weight distribution (MWD) of polyolefins by combining metallocene/methylalumoxane (MAO) catalysts is offered. Catalysts investigated were bis(cyclopentadienyl)zirconium dichloride (Cp2ZrCl2), its titanium and hafnium analogues (Cp2TiCl2 and Cp2HfCl2), as well as rac-ethylenebis(indenyl)zirconium dichloride (Et(Ind)2ZrCl2). As observed by other researchers, the MWD of polyethylene can be manipulated by combining soluble catalysts, which on their own produce polymer with narrow MWD but with different average molecular weights. Combined in slurry polymerization reactors, the catalysts in consideration produce ethylene homopolymer just as they would independently. Unimodal or bimodal MWDs can be obtained. This effect can be mimicked by blending polymers produced by the individual catalysts. We demonstrate how a variability in catalyst activity translates into a variability in MWD when mixing soluble catalysts in polymerization. Such a variability in MWD must be considered when setting goals for MWD control. We introduce a more quantitative approach to controlling the MWD using this method. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 831-840, 1998
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    Sulfonation of a poly(phenylquinoxaline) film (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1197-1199 
    Details
    ISSN: 0887-624X
    Keywords: sulfonation ; proton exchange membrane ; poly(phenylquinoxaline) ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    Thermosensitive lactitol-based polyether polyol (LPEP) hydrogels (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 979-984 
    Details
    ISSN: 0887-624X
    Keywords: lactitol ; hydrogel ; polyether polyol ; PEO and PPO linkage ; swelling degree ; thermosensitivity ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of new thermosensitive polymer hydrogels were prepared by reacting acylated poly(ethylene glycol) bis(carboxymethyl) ether (PEGBCOCl) with lactitol-based polyether polyols (LPEP). The polyether polyols were generated from propoxylation of lactitol and have molecular weights ranging from 1337 to 4055 g/mol. The hydrogels absorb water up to 1000% of their dry weight and expel free water at temperatures at and above 30°C. The wide ranging swelling behavior and excellent thermosensitivity depend closely on the degree of crosslinking and the propylene oxide lengths in the polyols. Differential scanning calorimetry of the hydrogels showed two endotherms associated with the phase transitions of PO and EO segments in the hydrogel structures. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 979-984, 1998
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    Kinetic and microstructure studies of poly(ethylene-co-p-methylstyrene) copolymers prepared by metallocene catalysts with constrained ligand geometry (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1017-1029 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This paper discusses the poly(ethylene-co-p-methylstyrene) copolymers prepared by metallocene catalysts, such as Et(Ind)2ZrCl2 and [C5Me4(SiMe2NtBu)]-TiCl2, with constrained ligand geometry. The copolymerization reaction was examined by comonomer reactivity (reactivity ratio and comonomer conversion versus time), copolymer microstructure (DSC and 13C-NMR analyses) and the comparisons between p-methylstyrene and other styrene-derivatives (styrene, o-methylstyrene and m-methylstyrene). The combined experimental results clearly show that p-methylstyrene performs distinctively better than styrene and its derivatives, due to the cationic coordination mechanism and spatially opened catalytic site in metallocene catalysts with constrained ligand geometry. A broad composition range of random poly(ethylene-co-p-methylstyrene)copolymers were prepared with narrow molecular weight and composition distributions. With the increase of p-methylstyrene concentration, poly(ethylene-co-p-ethylstyrene)copolymer shows systematical decrease of melting point and crystallinity and increase of glass transition temperature. At above 10 mol % of p-methylstyrene, the crystallinity of copolymer almost completely disappears. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1017-1029, 1998
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    Acid-catalyzed deprotection mechanism of tert-butyloxycarbonyloxy polymers in chemically amplified resists (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1035-1042 
    Details
    ISSN: 0887-624X
    Keywords: acid-catalyzed deprotection mechanism ; chemically amplified resist ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A mechanism of acid-catalyzed deprotection of poly(4-tert-butyloxycarbonyloxy-styrene), PBOCST, in chemically amplified resists has been elucidated in terms of elementary processes by means of semiempirical molecular orbital calculations. It is concluded that the overall deprotection of tert-butyloxycarbonyl (t-BOC) group proceeds stepwise; i.e., (a) the first products are an acid carbonate and a tert-butyl cation; (b) a phenolic compound is the secondary and final product from the acid carbonate, which is realized by assistance with a counter anion accompanied by acid; (c) the counter anion also assists acid regeneration from the tert-butyl cation to produce isobutylene. The yield rate of the phenol is proportional to the product of concentrations of the polymer, the catalytic acid, and the counter anion. The activation energy (21 kcal/mol) calculated for the rate-determining step (a) is in good agreement with an experiment. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1035-1042, 1998
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    Synthesis and properties of new polyamides derived from 1,4-bis(4-aminophenoxy)-2,5-di-tert-butylbenzene and aromatic dicarboxylic acids (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1069-1074 
    Details
    ISSN: 0887-624X
    Keywords: 1,4-bis(4-aminophenoxy)-2,5-di-tert-butylbenzene (BADTB) ; polyamides ; direct polycondensation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The diamine 1,4-bis(4-aminophenoxy)-2,5-di-tert-butylbenzene, containing symmetric, bulky di-tert-butyl substituents and a flexible ether unit, was synthesized and used to prepare a series of polyamides by the direct polycondensation with various aromatic dicarboxylic acids in N-methyl-2-pyrrolidinone (NMP) using triphenyl phosphite and pyridine as condensing agents. All the polymers were obtained in quantitative yields with inherent viscosities of 0.32-1.27 dL g-1. Most of these polyamides, except IIa, IId, and IIe, showed an amorphous nature and dissolved in polar solvents and less polar solvents. Polyamides derived from 4,4′-sulfonyldibenzoic acid, 4,4′-(hexafluoro-isopropylidene)dibenzoic acid, and 5-nitroisophthalic acid were even soluble in a common organic solvent such as THF. Most polyamide films could be obtained by casting from their N,N-dimethylacetamide (DMAc) solutions. The polyamide films had a tensile strength range of 49-78 MPa, an elongation range at break of 3-5%, and a tensile modulus range of 1.57-2.01 GPa. These polyamides had glass transition temperatures ranging between 253 and 276°C, and 10% mass loss temperatures were recorded in the range 402-466°C in nitrogen atmosphere. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1069-1074, 1998
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    Stereochemical and compositional assignment of acrylonitrile/methyl methacrylate copolymers by DEPT and inverse HECTOR NMR spectroscopy (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1081-1092 
    Details
    ISSN: 0887-624X
    Keywords: NMR ; microstructure ; acrylonitrile/methyl methacrylate copolymer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The acrylonitrile/methyl methacrylate copolymers of different monomer concentration were prepared by photo polymerization using uranyl ion as initiator. The carbon 13 and proton spectra of these copolymers are overlapping and complex. The complete spectral assignment of the 13C- and 1H-NMR spectra were done with the help of Distortionless Enhancement by Polarization Transfer (DEPT) and two dimensional 13C-1H Heteronuclear Single Quantum Correlation (HSQC) experiments. The methylene, methine and the methyl carbon resonances show both stereochemical (triad level) and compositional (dyad, triad, tetrad, pentad and hexad level) sensitivity. 2D Double Quantum Filtered Correlated Spectroscopy (DQFCOSY) experiment was used to ascertain the various geminal couplings between the methylene protons. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1081-1092, 1998
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    Self-propagating frontal copolymerization (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1117-1126 
    Details
    ISSN: 0887-624X
    Keywords: frontal copolymerization ; propagation velocity ; polymer chain ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The application of self-propagating frontal polymerization (FP) to synthesize copolymers has been investigated. Frontal copolymerizations of methyl methacrylate and methacrylic acid (MMA-MAA), acrylic acid and methacrylic acid (AA-MAA), and styrene and methacrylic acid (STY-MAA) with benzoyl peroxide (BPO) as initiator have been performed. The measured front velocities have been compared with the results of a suitably developed model. This is based on the pseudokinetic approach, accounts for the depropagation reaction, and is fully predictive; i.e., it does not include any adjustable parameter (although one had to be used for the specific experimental setup used in this work). An explicit, simplified solution of the model has been obtained using the constant pattern approximation. The microstructures of copolymers produced in bulk and by FP have been analyzed by differential scanning calorimetry. Their comparison indicates that self-propagating frontal copolymerization provides a substantial improvement in the uniformity of the chain composition distribution. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1117-1126, 1998
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    Vinyl monomers bearing chromophore moieties and their polymers. V. Synthesis and fluorescence behavior of a vinyloxy monomer bearing electron-accepting chromophore moiety, N-(2-(vinyloxy)ethyl)-1,8-naphthalimide, and its polymer (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1111-1116 
    Details
    ISSN: 0887-624X
    Keywords: N-(2-(vinyloxy)ethyl)-1,8-naphthalimide ; fluorescence structural self-quenching effect ; C60 ; electron donor ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A vinyloxy monomer bearing electron-accepting chromophore, N-(2-(vinyloxy)ethyl)-1,8-naphthalimide (VOENI), was synthesized by reaction of potassium 1,8-naphthalimide with 2-chloroethyl vinyl ether. VOENI can be homopolymerized by cationic initiation and copolymerized with maleic anhydride (MAn) under radical initiation. The fluorescence behaviors of VOENI and its polymers were investigated. It has been found that the fluorescence intensity of the VOENI monomer is much lower than that of its polymers at the same chromophore concentration. This means that a “structural self-quenching effect” (SSQE) has been also observed in the vinyloxy monomer consisting of an electron-accepting chromophore, which has opposite electronic structure in comparison with acrylates bearing electron-donating chromophores as we have reported previously. The SSQE is attributed to the charge-transfer interaction between the electron-accepting chromophore and the electron-donating double bond in the same molecule. The fluorescence quenching of 1,8-naphthalic anhydride and P(VOENI-co-MAn) by ethyl vinyl ether (EVE), dihydrofuran, triethylamine (TEA), etc. evidences that the electron-rich vinyloxy group does act as an important role in the SSQE of VOENI. C60 can also quench the fluorescence of the polymers, and an upward deviation from the linearity of the Stern-Volmer plot was observed showing that C60 acted as a powerful electron donor to quench the fluorescence of the copolymer. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1111-1116, 1998
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    Novel one-pot syntheses of sulfur-containing polymers from a bifunctional five-membered cyclic dithiocarbonate (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1189-1195 
    Details
    ISSN: 0887-624X
    Keywords: one-pot syntheses ; sulfur-containing polymers ; dithiol ; bifunctional five-membered cyclic dithiocarbonates ; diisocyanates ; acid dichlorides ; dibromoalkane ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Novel one-pot syntheses of sulfur-containing polymers from a bifunctional five-membered cyclic dithiocarbonate (1a) were carried out. Polythiourethanes were obtained by the polyaddition of 4,4′-methylenebis(phenyl isocyanate), tolylene 2,6-diisocyanate, and hexamethylene diisocyanate with a dithiol (2a) obtained by the reaction of 1a and benzylamine under mild conditions. Polythioesters were also obtained by the polycondensation of terephthaloyl and succinyl chlorides with 2a. Further, polythioether was obtained by the polycondensation of α,α′-dibromo-p-xylene with 2a. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1189-1195, 1998
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    Poly(arylene ether)s, poly(arylene thioether)s, and poly(arylene sulfone)s derived from a dihydroxy(imidoarylene) monomer (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1201-1208 
    Details
    ISSN: 0887-624X
    Keywords: poly(arylene ether) ; poly(arylene thioether) ; poly(arylene sulfone) ; polyimide ; pendent group ; one-pot polymerization ; thiocarbamate ; thermal stability ; high-performance polymer ; oxidation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Novel poly(arylene ether)s, poly(arylene thioether)s, and poly(arylene sulfone)s were synthesized from the dihydroxy(imidoarylene) monomer 1. The syntheses of poly(arylene ether)s were carried out in DMAc in the presence of anhydrous K2CO3 by a nucleophilic substitution reaction between the bisphenol and activated difluoro compounds. Poly(arylene thioether)s were synthesized according to the recently discovered one-pot polymerization reaction between a bis(N,N′-dimethyl-S-carbamate) and activated difluoro compounds in the presence of a mixture of Cs2CO3 and CaCO3. The bis(N,N′-dimethyl-S-carbamate) 3 was synthesized by the thermal rearrangement reaction of bis(N,N′-dimethylthiocarbamate) 2, which was synthesized from 1 by a phase-transfer catalyzed reaction. The poly(arylene thioether)s were further oxidized to form poly(arylene sulfone)s, which would be very difficult, if not impossible, to synthesize by other methods. All of the polymers described have extremely high Tgs and thermal stability as determined from DSC and TGA analysis. Poly(arylene sulfone)s have the highest Tgs and they are in the range of 298-361°C. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1201-1208, 1998
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    Synthesis and characterization of aromatic poly(ether ketone)s containing cyclotriphosphazene units (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1227-1232 
    Details
    ISSN: 0887-624X
    Keywords: cyclotriphosphazene ; aromatic poly(ether ketone) ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bis(4-oxybenzoic acid) tetrakis(phenoxy) cyclotriphosphazene (IUPAC name: 4-[4-(carboxyphenoxy)-2,4,6,6-tetraphenoxy-1,3,5,2λ5,4λ5,6λ5-triazatriphosphinin-2-yl]oxy-benzoic acid) was synthesized and direct polycondensed with diphenylether or 1,4-diphenoxybenzene in Eaton's reagent at the temperature range of 80-120°C for 3 hours to give aromatic poly(ether ketone)s. Polycondensations at 120°C gave polymer of high molecular weight. Incorporation of cyclotriphosphazene groups in the aromatic poly(ether ketone) backbone greatly enhanced the solubility of these polymers in common organic polar solvents. Thermal stabilities by TGA for two polymer samples of polymer series ranged from 390 to 354°C in nitrogen at 10% weight loss and glass transition temperatures (Tg) ranged from 81.4 to 89.6°C by DSC. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1227-1232, 1998
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    Preparation and thermotropic liquid crystalline properties of semirigid copolyurethanes composed of biphenyl units and partially fluorinated aliphatic chains (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1243-1249 
    Details
    ISSN: 0887-624X
    Keywords: semirigid copolyurethanes ; biphenyl unit ; fluorine-containing diols ; alkylene diphenyl dicarbamates ; melt polycondensation ; nematic phase ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New semirigid thermotropic liquid crystalline (LC) copolyurethanes 4 and 5 made up of biphenyl units and partially fluorinated aliphatic chains in the backbones were synthesized by melt polycondensation of a mixture of a dioxydihexanol of biphenyl 1 and two fluorine-containing diols 2a,b taken in definite feed mole ratios with alkylene diphenyl dicarbamates 3a-i having various lengths of aliphatic chains. The assigned structures of copolyurethanes 4 and 5 were identified by FTIR, 1H- and 13C-NMR spectra, and elemental analyses. The thermal and mesogenic properties were evaluated by differential scanning calorimetry (DSC), thermal mechanical analyses (TMA), polarizing microscopy, and temperature-changeable X-ray analyses, whose measurements indicated that the copolymers 4 and 5 form thermotropic nematic phases and have glass transition steps around room temperature. It is suggested that the incorporation of partially fluorinated aliphatic chains into the backbones has no drastic effect on the LC formation in the semirigid copolyurethanes 4 and 5. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1243-1249, 1998
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    Synthesis and characterization of a family of biodegradable poly(ester amide)s derived from glycine (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1271-1282 
    Details
    ISSN: 0887-624X
    Keywords: glycine ; synthesis ; biodegradation ; poly(ester amide)s ; thermal analysis ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of aliphatic poly(ester amide)s derived from 1,6-hexanediol, glycine, and diacids with a variable number of methylenes (from 2 to 8) have been synthesized and characterized. Infrared spectroscopy shows that the studied polymers present a unique kind of hydrogen bond that is established between their amide groups. Thermal properties as melting, glass transition, and decomposition temperatures are reported. The data indicate that all the polymers are highly crystalline. Thus, different kinds of spherulites (positive and/or negative) were obtained depending on the preparation conditions and on the polymer samples. Moreover, all the polymers crystallized from dilute diol solutions as ribbonlike crystals where a regular folding habit and a single hydrogen bond direction could be deduced. A test of enzymatic hydrolysis was employed to assess the potential biodegradability of these polymers. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1271-1282, 1998
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    Synthesis and characteristics of polydepsipeptide with pendant thiol groups (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1283-1290 
    Details
    ISSN: 0887-624X
    Keywords: biodegradability ; oligo[(glycolic acid)-alt-(L-cysteine)] ; poly[(lactic acid)-depsipeptide] ; ring-opening polymerization ; pendant thiol group ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: To obtain water-soluble oligodepsipeptide with pendant thiol groups, the alternating co-oligomer [oligo(Glc-alt-Cys)], consisting of glycolic acid (Glc) and L-cysteine (Cys) residues as α-hydroxy acid and α-amino acid residues, respectively, was prepared by means of ring-opening homo-oligomerization of cyclo[Glc-Cys(MBzl)] and subsequent deprotection of methoxybenzyl groups. Moreover, to modify the properties of poly(lactic acid) [poly(LA)] and to introduce pendant thiol groups to poly(LA), the terpolymer of LA, Glc, and Cys {poly[LA-(Glc-Cys)]} was synthesized through ring-opening and copolymerization of L-lactide with the protected cyclodepsipeptide, cyclo[Glc-Cys(MBzl)] and subsequent deprotection of methoxybenzyl groups. By changing the mol fraction of (Glc-Cys) unit, the solubility, thermal transition, degradation behavior of the modified poly(LA), and the water contact angle of its film could be varied. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1283-1290, 1998
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    Synthesis of poly(1,4-dioxan-2-one-co-trimethylene carbonate) for application in drug delivery systems (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1301-1307 
    Details
    ISSN: 0887-624X
    Keywords: 1,4-dioxan-2-one ; trimethylene carbonate ; stannous octoate ; drug delivery system ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(1,4-dioxan-2-one-co-trimethylene carbonate), P(DON-co-TMC), copolymers with different compositions were synthesized by copolymerizations of 1,4-dioxan-2-one (DON) and trimethylene carbonate (TMC) at 120°C in the presence of Sn(Oct)2. Their structures and compositions were determined with FT-IR and 1H-NMR spectroscopies. The intrinsic viscosities of copolymers increased with the increase of the TMC fraction in feed. The DSC results of copolymers showed that the glass transition temperatures (Tgs) of copolymers are lower than those of homopolymers. Most copolymers are amorphous except for one with a high DON composition. The hydrophilicity of the copolymers is in proportion with the DON molar fraction in the copolymers. It was found that the Levonorgestrel (LNG) release rate is dependent of the composition and flexibility of polymer chains. The fastest one is the copolymer with nearly a equivalent fraction of DON to TMC. Among copolymers with other compositions, a higher DON fraction would be favorable to the release of LNG. All measurements demonstrate an almost constant release rate in the period of 1 month. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1301-1307, 1998
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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