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  • Polymer and Materials Science  (112,478)
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  • 101
    Electronic Resource
    Electronic Resource
    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
    Additional Material: 4 Ill.
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  • 102
    Electronic Resource
    Electronic Resource
    Importance of active-site reactivity and reaction conditions in the preparation of hyperbranched polymers by self-condensing vinyl polymerization: Highly branched vs. linear poly[4-(chloromethyl)styrene] by metal-catalyzed “living” radical polymerization (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 955-970 
    Details
    ISSN: 0887-624X
    Keywords: hyperbranched ; self-condensing vinyl polymerization ; metal catalyzed ; living radical ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The self-condensing vinyl polymerization of 4-(chloromethyl)styrene using metal-catalyzed living radical polymerization catalyzed by the complex CuCl/2,2′-bipyridyl has been attempted. Given the unequal reactivity of the two potential propagating species in this system, a variety of polymerization conditions were tested to optimize the extent of branching in the products. Typical reaction conditions included polymerization in the bulk, or preferably in chlorobenzene solution, with catalyst to monomer ratios in the range 0.01-0.30, temperatures of 100-130°C, and reaction times from 0.1 to 32 h. Polymers with weight average molecular weights between 3 × 103 and 1.6 × 105 and different extents of branching are formed as evidenced by size-exclusion chromatography, light scattering, and NMR analysis of the reaction products. The influence of reaction conditions on the molecular weight and branching of the resulting polymers is discussed in detail. In sharp contrast to an earlier report, the weight of evidence suggests that, at a catalyst to monomer ratio of 0.01, an almost linear polymer is obtained, while a high catalyst to monomer ratio favors the formation of a branched structure. As a result of the unequal reactivity of the primary and secondary benzylic halide reactive sites, growth occurs by a modified self-condensing vinyl polymerization mechanism that involves incorporation of the largely linear vinyl-terminated fragments formed early on in the polymerization into the vinyl polymer, to afford an irregularly branched structure. Chemical transformations involving the numerous benzylic halide functionalities of the highly branched polymer have been investigated. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 955-970, 1998
    Additional Material: 11 Ill.
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  • 103
    Electronic Resource
    Electronic Resource
    Autoacceleration and inhibition: Free volume. Epoxy-amine kinetics (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1001-1016 
    Details
    ISSN: 0887-624X
    Keywords: free volume ; autoacceleration ; inhibition ; tertiary amines ; friction coefficient ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The epoxy-diamine cure process was studied. We found that the mechanism can be described in three steps: (i) initiation up to 20-25% of conversion. (ii) autoacceleration and (iii) inhibition. It has been observed that after the initiation there is a clear autoacceleration effect which has been explained in terms of free volume, considerations: the volume occupied by the products of reaction diminishes the available volume increasing the “local concentration” of the reactants and therefore the rate of reaction. The reaction was followed by FTIR (near infrared) as the main technique. We used a purified epoxy resin as well as phenyl glycidyl ether cured with m-xylenediamine. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1001-1016, 1998
    Additional Material: 11 Ill.
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  • 104
    Electronic Resource
    Electronic Resource
    Formation of quinoid fragments in vacuum-deposited poly-para-phenylene films: IR spectroscopy evidence (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1043-1052 
    Details
    ISSN: 0887-624X
    Keywords: poly-para-phenylene ; quinoid structure ; IR spectroscopy ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The structure of vacuum-deposited poly-para-phenylene (PPP) films prepared from a high-molecular-weight PPP powder has been investigated by IR spectroscopy. It has been demonstrated that in IR spectra of PPP films exhibiting intense luminescence an extremely strong band at 1375 cm-1 is observed, which is not typical for currently known PPP modifications. Based on the IR spectral data, the model of formation of a PPP chain with quinoid fragments in the ground electronic state is proposed. The structure of defects that inevitably spring up during the benzenoid-quinoid transition is discussed. High intensity of the band at 1375 cm-1 is associated with the change in the order of the “defect” C—C bond between adjacent quinoid and benzenoid units. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1043-1052, 1998
    Additional Material: 6 Ill.
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  • 105
    Electronic Resource
    Electronic Resource
    Synthesis and characterization of new soluble polyamides based on 3,3′,5,5′-tetramethyl-2,2- bis[4-(4-aminophenoxy)phenyl]propane and various aromatic dicarboxylic acids (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1075-1080 
    Details
    ISSN: 0887-624X
    Keywords: 3,3′,5,5′-tetramethyl-2,2-bis[4-(4-aminophenoxy)phenyl]propane (TBAPP) ; direct polycondensation ; polyamides ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of new soluble polyamides having isopropylidene- and methyl-substituted arylene ether moieties in the polymer chain were prepared by the direct polycondensation of 3,3′,5,5′-tetramethyl-2,2-bis[4-(4-aminophenoxy)phenyl]propane (TBAPP) and various aromatic dicarboxylic acids in N-methyl-2-pyrrolidinone (NMP) using triphenyl phosphite and pyridine as condensing agents. Polymers were produced with high yield and moderate to high inherent viscosities of 0.87-1.56 dL g-1. All the polymers could be readily dissolved in polar aprotic solvents such as NMP, N,N-dimethylacetamide and N,N-dimethylformamide, as well as less polar solvents such as m-cresol and pyridine. Some of them were even soluble in tetrahydrofuran. These polymers were solution-cast into transparent, flexible, tough films which were further characterized by x-ray and mechanical analysis. All of the polymers were amorphous and the polyamide films had a tensile strength range of 51-100 MPa, an elongation at break range of 4-11%, and a tensile modulus range of 1.90-2.53 GPa. These polyamides had glass transition temperatures between 188-255°C and 10% mass loss temperatures in the range of 439-468 and 454-483°C in nitrogen and air atmosphere, respectively. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1075-1080, 1998
    Additional Material: 1 Ill.
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  • 106
    Electronic Resource
    Electronic Resource
    New polar silane-PEO polyester complexes as polymer electrolytes (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1093-1106 
    Details
    ISSN: 0887-624X
    Keywords: ion-conducting polymers ; silicon ; synthesis ; stability ; conductivity ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Trifunctional carbosilanes containing hydroxy and cyano groups have been synthesized in good yields and incorporated into polyether-based electrolytes. The new linear and cross-linked modified PEOs have been characterized by DSC and conductivity measurements. The effect of silane content, the length of the PEO block, glycerol concentration, and temperature on glass transition temperature and conductivity of lithium salts complexes of these materials has been evaluated. The new materials showed improved conductivity (∼ 10-5 S cm-1) at ambient temperatures compared with unmodified polyethers. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1093-1106, 1998
    Additional Material: 6 Ill.
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  • 107
    Electronic Resource
    Electronic Resource
    Synthesis and properties of poly(amide-imide)s based on the diimide-diacid condensed from 2,2′- bis(4-aminophenoxy)biphenyl and trimellitic anhydride (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1169-1177 
    Details
    ISSN: 0887-624X
    Keywords: poly(amide-imide)s ; 2,2′-bis(4-trimellitimidophenoxy) biphenyl ; solubility ; 2,2′-bis(4-aminophenoxy)biphenyl ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new dicarboxylic acid having a kinked structure was synthesized from the condensation of 2,2′-bis(4-aminophenoxy)biphenyl and trimellitic anhydride. A series of biphenyl-2,2′-diyl-containing aromatic poly(amide-imide)s having inherent viscosities of 0.23-0.94 dL/g was prepared by the triphenyl phosphite activated polycondensation from the diimide-diacid II with various aromatic diamines in a medium consisting of N-methyl-2-pyrrolidone (NMP), pyridine, and calcium chloride. Most of the resulting polymers showed an amorphous nature and were readily soluble in a variety of organic solvents including NMP and N,N-dimethylacetamide (DMAc). Transparent, flexible, and tough films of these polymers could be cast from DMAc or NMP solutions. The glass transition temperatures of these polymers were in the range of 227-261°C and the 10% weight loss temperatures were above 520°C in nitrogen. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1169-1177, 1998
    Additional Material: 3 Ill.
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  • 108
    Electronic Resource
    Electronic Resource
    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
    Additional Material: 3 Ill.
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  • 109
    Electronic Resource
    Electronic Resource
    Synthesis and cationic photopolymerization of 1-butenyl glycidyl ether (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1179-1187 
    Details
    ISSN: 0887-624X
    Keywords: 1-butenyl glycidyl ether ; photoinitiated cationic polymerization ; diaryliodonium salts ; cyclopolymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1-Butenyl glycidyl ether was prepared in high yield by the ruthenium-catalyzed isomerization of crotyl glycidyl ether. This ambifunctional monomer underwent facile photoinitiated cationic polymerization using diaryliodonium salts as photoinitiators. The progress of the polymerizations was followed using Fourier transform real-time infrared spectroscopy, and the reactivity of this monomer under various experimental conditions determined. A comparison of the rates of polymerization of the epoxy and vinyl ether groups suggested that the polymerization may take place by an intramolecular cyclization process that generates cyclic acetal units in the backbone of the polymer. It was further shown that crotyl glycidyl ether undergoes regioselective cationic ring-opening polymerization to give a polyether, and then isomerization was carried out to give an oligomer bearing reactive pendant 1-butenyl ether groups. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1179-1187, 1998
    Additional Material: 8 Ill.
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  • 110
    Electronic Resource
    Electronic Resource
    Pulse radiolysis studies of poly(methyl methacrylate) containing pyrene (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1209-1215 
    Details
    ISSN: 0887-624X
    Keywords: poly(methyl methacrylate) ; pyrene ; pulse radiolysis ; radical ion decay ; ion recombination ; fluorescence ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A pulse radiolysis study of poly(methyl methacrylate) in the presence of pyrene has been carried out in the temperature range 100-295 K. The concentration of pyrene was changed from 10-3 to 10-1 mol dm-3. The absorption/emission spectra and kinetics of solute excited states and solute radical ions were investigated. It was found that pyrene excited states were formed as a result of their radical ion recombination in a time scale up to seconds. The decay of solute radical ions was influenced by photobleaching and can be described by a time-dependent rate constant. The activation energy of Py ions decay was temperature dependent and was equal to 35.7 and 1.2 kJ/mol for temperatures 〉Tγ and 〈Tγ, respectively, where Tγ ∼ 175 K represented the transition temperature responsible for γ-relaxation. The reaction mechanism was proposed. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1209-1215, 1998
    Additional Material: 7 Ill.
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  • 111
    Electronic Resource
    Electronic Resource
    Anionic synthesis of aromatic amide and carboxyl functionalized polymers. Chain-end functionalization of poly(styryl)lithium with N,N-diisopropyl-4-(1-phenylethenyl)benzamide (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1233-1241 
    Details
    ISSN: 0887-624X
    Keywords: living anionic polymerization ; poly(styryl)lithium ; functionalization ; aromatic carboxylation ; N,N-diisopropylamide ; N,N-diisopropyl-4-(1-phenylethenyl)-benzamide ; substituted 1,1-diphenylethylenes ; functionalized polystyrene ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The novel syntheses of N,N-diisopropyl-4-benzoylbenzamide, N,N-diisopropyl-4-(1-hydroxy-1-phenylethyl)benzamide, and N,N-diisopropyl-4-(1-phenylethenyl)benzamide (1) are described. ω-Amidopolystyrene (2) was synthesized in quantitative yields by the reaction of poly(styryl)lithium with stoichiometric amounts of N,N-diisopropyl-4-(1-phenylethenyl)benzamide (1) in toluene/tetrahydrofuran (4 : 1 v/v) at -78°C. Deblocking of the amide protecting group by acid hydrolysis quantitatively provides the corresponding aromatic carboxyl chain-end functionalized polystyrene (3). The functionalization agent and functionalized polymers were characterized by HPLC, thin-layer chromatography, size exclusion chromatography, vapor phase osmometry, spectroscopy (1H-NMR, 13C-NMR, and FTIR), potentiometry, and elemental analysis. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1233-1241, 1998
    Additional Material: 3 Ill.
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  • 112
    Electronic Resource
    Electronic Resource
    Synthesis of novel polyaryl(ether-ketones) with tert-butyl pendent groupsDedicated to Prof. F. J. Baltaá Calleja on the occasion of his 60th birthday. (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1251-1256 
    Details
    ISSN: 0887-624X
    Keywords: ether ketones ; synthesis ; NMR ; thermal properties ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Linear polyaryl(ether ketones) containing tert-butyl pendent groups were prepared from aromatic hydrocarbons and aromatic diacid chlorides, both classes of monomers containing tert-butyl pendent groups. The polymers were prepared in high yield and high molecular weight by low-temperature precipitation polycondensation in 1,2-dichloroethane. The presence of meta-oriented moieties and bulky pendent groups played a beneficial role with regard to solubility, while the thermal transitions and thermal resistance were not greatly impaired relative to conventional all para-oriented polyaryl(ether-ketones). The current polyaryl(ether-ketones) showed glass transition temperatures in the range 170-240°C and decomposition temperatures, as measured by TGA, of about 500°C. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1251-1256, 1998
    Additional Material: 3 Ill.
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  • 113
    Electronic Resource
    Electronic Resource
    New polymer syntheses. XCVI. Star-shaped LC-polyesters derived from β-(4-hydroxyphenyl)propionic acid and 4-hydroxybenzoic acid (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1387-1395 
    Details
    ISSN: 0887-624X
    Keywords: star-shaped polyesters ; nematic phase ; phloritic acid ; spirobis indane ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Star-shaped polyesters were prepared by polycondensation of tetraacetoxyspirobis(indane) and a 1 : 1 mixture of silylated β-(4-acetoxyphenyl)propionic acid and silylated 4-acetoxybenzoic acid. The lengths of the star arms were systematically varied, and the influence of the star center on the stability of the nematic phase was studied. It was found that on the average more than 10 monomer units per star arm are required to stabilize a homogeneous LC-phase. Furthermore, a second class of star-shaped polyesters consisting of β-(4-hydroxyphenyl)propionic acid (HPPA), 4-hydroxybenzoic acid (HBA), and 6-hydroxy-2-naphthoic acid (HNA) was prepared. This ternary copolyester proved to reduce the crystallinity but to stabilize the LC-character. A homogeneous nematic melt was obtained with 6 monomer units per star arm. This interpretation is based on optical microscopy which provides a static picture of the biphasic situation. Therefore, a preliminary study of the melt rheology was included, which proved that the typical LC-character of the melt was detectable ateven shorter star arms due to the shear orientation. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1387-1395, 1998
    Additional Material: 7 Ill.
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  • 114
    Electronic Resource
    Electronic Resource
    Structural effect of polymeric acid dopants on the characteristics of doped polyaniline composites: Effect of hydrogen bonding (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1431-1439 
    Details
    ISSN: 0887-624X
    Keywords: polyaniline ; polymeric acid dopant ; conducting polymer ; doping level ; chain alignment ; conductivity ; hydrogen bonding ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The conductivities of polyaniline (PANi) composites doped with the copolymeric acids such as poly(methyl methacrylate-co-p-styrenesulfonic acid) (PMMA-co-SSA), poly(styrene-co-p-styrenesulfonic acid) (PS-co-SSA), and poly(methyl methacrylate-co-2-acrylamido-2-methyl-1-propanesulfonic acid) (PMMA-co-AMPS) were investigated as a function of the acid content in the copolymeric acid dopants. With the fixed ratio of acid to aniline (1/1) in the PANi composites, the conductivities of the copolymeric acid-doped PANis decreased as the acid content in the copolymeric acids decreased. This could be attributed to the nonacidic units in the copolymeric acids which seemed to prevent adjacent acid groups from doping the PANi. Among the three kinds of copolymeric acid dopants, the PMMA-co-SSA series doped the PANi most effectively, and consequently, the PMMA-co-SSA-doped PANi composites showed the highest conductivities. The lack of conductivities of the PMMA-co-AMPS-doped PANi composites seems to be due to the doping ability of the AMPS groups. The higher conductivities of the PMMA-co-SSA-doped PANi composites rather than the PS-co-SSA-doped ones were attributed to the hydrogen bonding formed between the carbonyl groups in MMA and the amine groups in aniline which may hinder the phase separation and induce more homogeneous mixing and efficient doping. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1431-1439, 1998
    Additional Material: 8 Ill.
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  • 115
    Electronic Resource
    Electronic Resource
    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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  • 116
    Electronic Resource
    Electronic Resource
    Macrocycles IV. Macrocyclic polylactones as bifunctional monomers for polycondensations (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1373-1378 
    Details
    ISSN: 0887-624X
    Keywords: macrocyclic polymerization ; polycondensation ; 2-stanna-1,3-dioxacycloalkanes ; poly(ε-caprolactone) ; poly(δ-valerolactone) ; poly(β-D,L-butyrolactone) ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Tin containing macrocyclic polylactones were prepared by di-n-butyl-2-stanna-1,3-dioxepane-initiated polymerizations of ε-caprolactone in bulk. The average ring size was varied from 10 to 100 monomer units via the monomer/initiator (M/I) ratio. Addition of terephthaloyl or sebacoyl chloride to the in situ prepared macrocycles yielded polycondensates under elimination of di-n-butyl tin dichloride. The molecular weights increased with the reaction temperature (e.g., 80-140°C) and with the size of the macrocycles. Number-average molecular weights (Mns) up to 90,000 and polydispersities between 1.65 and 2.0 were obtained. Further polycondensations were conducted with isophthaloyl chloride, 4,4′-biphenyldicarbonylchloride and 4,4′-phenylenebisacryloylchloride. Several polycondensations were performed with macrocyclic poly (δ-valerolactone) and poly (β-D,L-butyrolactone). In those cases the increase of the molecular weight was lower. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1373-1378, 1998
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  • 117
    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
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  • 118
    Electronic Resource
    Electronic Resource
    Anomalous viscosity behavior of rodlike polyelectrolytes: Partially sulfonated poly(2-benzoyl-1,4-phenylene)s in aqueous solution (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1425-1429 
    Details
    ISSN: 0887-624X
    Keywords: anomalous viscosity ; rodlike polyelectrolytes ; sulfonated poly(2-benzoyl-1,4-phenylene) ; aqueous solution ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two stereoisomeric poly(2-benzoyl-1,4-phenylene)s were synthesized. Polymer I has exclusively a head-to-tail structure; however, polymer II contains both head-to-head and head-to-tail units. The sulfonation reaction of polymers I and II was found to occur mainly on the meta position of the benzoyl group on the phenylene backbone. The viscosities of polymers Ia (27% sulfonated) and Ic (51% sulfonated) in aqueous solutions at 25°C were measured with and without NaBr addition. Upon the addition of NaBr (0.05 and 0.1M), the reduced viscosities were found to increase gradually and reach a constant value in each case after standing at room temperature for 30-40 h. Without NaBr, the time effect was not found. The reduced viscosities of solutions with NaBr were also higher than those without the salt. These results are quite different from the typical “polyelectrolyte” behavior. A possible explanation of the salt effect of rigid rodlike polymers such as sulfonated poly(2-benzoyl-1,4-phenylene) is discussed. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1425-1429, 1998
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    Living polymers. Their discovery, characterization, and properties (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. IX 
    Details
    ISSN: 0887-624X
    Keywords: living polymerization ; discovery ; significance ; revised definition ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The story of the discovery of living polymers is presented. Living polymers are polymers that retain their ability to propagate and grow to a desired size while their degree of termination or chain transfer is still negligible. Theoretical and mechanistic considerations are discussed. The living polymerization technique provides access to uniform polymers (Poisson molecular weight distribution) of controllable size, block copolymers, functional polymers, and star and comb-shaped polymers. The quantitative aspects of electron transfer are fully discussed. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: ix-xv, 1998
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    Controlling surfaces and interfaces with functional polymers: Preparation and functionalization of dendritic-linear block copolymers via metal catalyzed “living” free radical polymerization (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1-10 
    Details
    ISSN: 0887-624X
    Keywords: living free-radical polymerization ; dendrimer ; polystyrene ; block copolymer ; chemical modification ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The preparation and chemical modification of dendritic-linear block copolymers with surface functionalized dendritic components are presented. Isophthalate ester-functionalized dendrons featuring benzylic halide groups at their focal points have been used for the metal catalyzed “living” radical polymerization of styrene. The molecular weight of the dendritic-linear block copolymers determined by MALDI-TOF and Size Exclusion Chromatography was found to be accurately controlled up to molecular weights of ca. 30,000 a.m.u., with polydispersities less than 1.2. Subsequent functional group modifications of the peripheral ethyl ester groups of the dendritic block have been successfully carried out leading to carboxylic acids, butyl amides, benzyl alcohols, benzyl halides, and also accelerated generation growth via transesterification with a first generation dendritic alcohol. Several of these new dendritic-linear block copolymers exhibit interesting aggregation characteristics as evidenced by 1H-NMR spectroscopic studies. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1-10, 1998
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    Effects of complex formation and cyclization in radical copolymerization of allyl(metha)acrylates with maleic anhydride (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1501-1508 
    Details
    ISSN: 0887-624X
    Keywords: copolymerization ; charge transfer complex ; cyclization ; allyl acrylate ; allyl methacrylate ; maleic anhydride ; chain growth reactions ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Radical copolymerization of allyl acrylate (AA) and allyl methacrylate (AMA) as bifunctional monomers of donor (allyl)-acceptor (acryl) type with maleic anhydride (MA) as an acceptor monomer were carried out in metrhyl ethyl ketone (MEK) at 50-70°C in the presence of 2,2′-azoisobutyronitrile (AIBN) as initiator. Constants of complex formation (Kc), cyclization (kcl), and copolymerization (r1, r2, r1c, r1c1, and r1c2) as well as energies of activation for cyclization (Eac) and copolymerization reactions (Ea), and orders for the monomer (m) and initiator (n) concentrations were determined. The following values were found, for AA and AMA, respectively: Kc = 0.038 and 0.11 L/mol in deutered acetone at 35 ± 0.1°C, kcl = 6.45 and 6.53, r1 = 0.083 ± 0.005 and 0.028 ± 0.002, r2 = 0.027 ± 0.002 and 0.063 ± 0.003 (by the Kelen-Tüdös method), r1c = 0.04 and 0.025, r1c1 = 0.128 and 0.176, r1c2 = 0.127 and 0.177 (by the Seiner-Litt equation), Eac = 28.9 and 28.7 kJ/mol, Ea = 67.0 and 87.9 kJ/mol, m = 1.53 and 1.45, and n = 0.50 and 0.52. The presence of cyclic, unsaturated, and anhydride fragments in the macromolecules was confirmed with FTIR data and chemical (iodometrical and potentiometric titrations) analysis. It was established that complex formation in the monomer systems studied is the main factor for alternating cyclocopolymerization leading to formation of copolymers containing lactone and linear-unsaturated fragments in the macromolecular chain. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1501-1508, 1998
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    Optical anisotropy of a photoreacted side-chain liquid-crystalline polymer induced by linearly polarized UV light (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1521-1526 
    Details
    ISSN: 0887-624X
    Keywords: liquid-crystalline polymer ; photoreaction ; polarized UV photoreaction ; optical anisotropy ; liquid-crystalline alignment ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Linearly polarized (LP) UV photoreaction of a photo-crosslinkable side-chain liquid-crystalline polymer (SLCP) containing photoreactive cinnamoyl and biphenyl mesogenic groups (1) was studied. The optical anisotropy of the polymer film was induced by the LP-UV photoreaction and was investigated by the temperature-controlled polarized UV absorption spectroscopy and polarized FT-IR measurements. The reorientation of the nonreacted mesogenic groups along to the Ê direction of the incident LP-UV light during the photoreaction occurred at the LC temperature range of the polymer, and the induced birefringence Δn was about 0.02. Because of the high-density photo-crosslinking, the LP-UV photoreacted film showed orientational stability up to 160°C. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1521-1526, 1998
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    Kinetics and mechanisms of emulsion polymerization of vinylidene chloride. I. Effects of operating variables on the rate of polymerization and the number of polymer particles produced (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1919-1928 
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    ISSN: 0887-624X
    Keywords: emulsion polymerization ; vinylidene chloride ; kinetics ; sodium lauryl sulfate ; potassium persulfate ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Emulsion polymerization of vinylidene chloride was carried out at 50°C using sodium lauryl sulfate as emulsifier and potassium persulfate as initiator, respectively. Contrary to the results so far reported, the stirring rate did not affect the progress of the polymerization and such an abnormal kinetic behavior as the rate of polymerization suddenly drops in the course of polymerization was not observed. The number of polymer particles produced was proportional to the 0.7 power of the concentration of emulsifier forming micelles and to the 0.3 power of the initial initiator concentration, respectively, and was independent of the initial monomer concentration. The rate of polymerization was in proportion to the 0.3 power of the concentration of emulsifier forming micelles, to the 0.5 power of the initial initiator concentration, to the 0.2 power of the initial monomer concentration, and to the 0.45 power of the number of polymer particles, respectively. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1919-1928, 1998
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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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    Reactions on polymers with amine groups. V. Addition of pyridine and imidazole groups with acetylenecarboxylic acids (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1615-1623 
    Details
    ISSN: 0887-624X
    Keywords: chemically modified polymers ; addition reactions ; unsaturated betaines ; reaction kinetics ; pyridine ; imidazole ; photocrosslinking polymers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Unsaturated macromolecular carboxybetaines were obtained by reaction of poly(4-vinylpyridine) and poly(N-vinylimidazole) with propiolic acid. A kinetic model was presented for 4-methylpyridine. It consists of three coupled reactions: neutralization, addition which involves two molecules of acid and leads to a cation-anion pair structure, where the cation results from the addition of the amine nitrogen to the triple bond of acid, and an equilibrium reaction between the ion-pair structure and the betaine structure. The addition rate was found to be higher for poly(4-vinylpyridine) than for poly(N-vinylimidazole); it was also higher in water than in a water-methanol mixture. The reaction with acetylenedicarboxylic acid was carried out on poly(N-vinylimidazole), but the transformed units showed the structure that results from propiolic acid. The betaine products from 4-methylpyridine did not polymerize by radical initiation. The polymeric products show characteristics of photocrosslinking polymers. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1615-1623, 1998
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    Synthesis and characterization of aromatic poly(ether sulfone imide)s derived from sulfonyl bis(ether anhydride)s and aromatic diamines (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1649-1656 
    Details
    ISSN: 0887-624X
    Keywords: bis(ether anhydride) ; poly(ether sulfone imide) ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two sulfonyl group-containing bis(ether anhydride)s, 4,4′-[sulfonylbis(1,4-phenylene)dioxy]diphthalic anhydride (IV) and 4,4′-[sulfonylbis(2,6-dimethyl-1,4-phenylene)dioxy]diphthalic anhydride (Me-IV), were prepared in three steps starting from the nucleophilic nitrodisplacement reaction of the bisphenolate ions of 4,4′-sulfonyldiphenol and 4,4′-sulfonylbis(2,6-dimethylphenol) with 4-nitrophthalonitrile in N,N-dimethylformamide (DMF). High-molar-mass aromatic poly(ether sulfone imide)s were synthesized via a conventional two-stage procedure from the bis(ether anhydride)s and various aromatic diamines. The inherent viscosities of the intermediate poly(ether sulfone amic acid)s were in the ranges of 0.30-0.47 dL/g for those from IV and 0.64-1.34 dL/g for those from Me-IV. After thermal imidization, the resulting two series of poly(ether sulfone imide)s had inherent viscosities of 0.25-0.49 and 0.39-1.19 dL/g, respectively. Most of the polyimides showed distinct glass transitions on their differential scanning calorimetry (DSC) curves, and their glass transition temperatures (Tg) were recorded between 223-253 and 252-288°C, respectively. The results of thermogravimetry (TG) revealed that all the poly(ether sulfone imide)s showed no significant weight loss before 400°C. The methyl-substituted polymers showed higher Tg's but lower initial decomposition temperatures and less solubility compared to the corresponding unsubstituted polymers. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1649-1656, 1998
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    Synthesis and radical polymerization of a novel acrylamide having an α-helical peptide structure in the side chain (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1679-1682 
    Details
    ISSN: 0887-624X
    Keywords: radical polymerization ; acrylamide ; helical peptide ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 3 Ill.
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    The role of multifunctionalized amine structure and reaction conditions on the transformations of crosslinked copoly(styrene-p-nitrophenylacrylate) (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1699-1706 
    Details
    ISSN: 0887-624X
    Keywords: crosslinked copoly (styrene-p-nitrophenylacrylate) ; nucleophilic substitution ; primary amines ; diaminoalkanes ; amino alcohols ; amino acids ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Crosslinked copoly(styrene-p-nitrophenylacrylates), containing 2% (1) or 4% DVB (2) were converted with various diaminoalkanes (1,2-diaminoethane 3a, 1,4-diaminobutane 3b, 1,8-diaminooctane 3c) to amides. The degree of additional crosslinking depended on the chain length of the diaminoalkane, the molar ratio of ester function in 1 or 2 to diaminoalkane, solvent polarity (dimethylformamide, chloroform, toluene), while reaction temperature (50 or 100°C) had only a minor effect. 2 was also converted with various amines bearing additional functional groups (ethanolamine, 3-amino-1-propanol, 4-aminomethylpyridine, 2-(2-aminoethylamino)-ethanol, 2-(2-aminoethoxy)-ethanol, 6-aminocaproic acid, N-propylaminomorpholine, 3-N,N-diethylamino-1-propylamine) to the corresponding amides. The swelling ability of the resins depended on the crosslinking of the starting copoly(styrene-p-nitrophenylacrylate) (1, 2), the structure of the amide, the degree of additional crosslinking, and solvent polarity (chloroform, dimethylformamide, methanol, toluene). The accessibility of nitrogen atoms in the polymer matrix was examined by EtX functionalization of the 3-N,N-diethylamino-1-propylamine derivative (10) and 4-aminomethylpyridine derivative (13), and more than 85% functionalization was found. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1699-1706, 1998
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    Thermo-oxidatively stable polyimides and their chemical structures (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1717-1723 
    Details
    ISSN: 0887-624X
    Keywords: thermo-oxidative stability ; polyimide ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of aromatic diamines having ether and/or carbonyl moieties in their structures were synthesized. By using these synthesized diamines and commercially available tetracarboxylic dianhydrides, various kinds of polyimides having ether and/or carbonyl moieties were synthesized. The thermo-oxidative stability of the obtained polyimides was investigated by focusing on the chemical structures of their repeating structure units. The reason for the improved thermo-oxidative stability of the ether-carbonyl polyimide structure was explained by an electronically balanced condition, i.e., the balance of electron donor moiety ( - O - ) and electron acceptor moiety ( - CO - ) in a chemical structure, and the degree of electron deficiency of the benzene-imide ring structure. The possibility of the formation of a charge transfer complex (CT-complex) was also mentioned as an explanation of the improved thermo-oxidative stability of ether-carbonyl polyimide structures. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1717-1723, 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
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    Synthesis and properties of new soluble N-phenyl-substituted aromatic-aliphatic and all aromatic polyamides derived from 4,4′-dianilinobiphenyl (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2193-2200 
    Details
    ISSN: 0887-624X
    Keywords: N-phenylated polyamides ; 4,4′-dianilinobiphenyl ; solubility ; thermal behavior ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New N-phenylated aromatic-aliphatic and all aromatic polyamides were prepared by the high-temperature solution polycondensation of 4,4′-dianilinobiphenyl with both aliphatic (methylene chain lengths of 6-11) and aromatic dicarboxylic acid chlorides. All of the aromatic-aliphatic polyamides and the wholly aromatic polyamides exhibited an amorphous nature and good solubility in amide-type and chlorinated hydrocarbon solvents, except for those aromatic polyamides containing p-oriented phenylene or biphenylylene linkages in the backbone; the latter were crystalline and insoluble in organic solvents except m-cresol. The N-phenylated aromatic-aliphatic polyamides and aromatic polyamides had glass transition temperatures in the range of 79-116°C and 207-255°C, respectively, and all the polymers were thermally stable with decomposition temperatures above 400°C in air. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2193-2200, 1998
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    Structure analysis of a soluble polysiloxane-block-polyimide and kinetic analysis of the solution imidization of the relevant polyamic acid (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2237-2245 
    Details
    ISSN: 0887-624X
    Keywords: NMR ; polysiloxane, polysiloxane-block-polyimide ; solution imidization ; kinetic analysis ; structure analysis ; spin-lattice relaxation time ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of polysiloxane-block-polyimides were synthesized by solution imidization of the polyamic acids derived from the combination of 3,3′,4,4′-diphenylsulfonetetracarboxylic dianhydride (DSDA), 2,2-bis[4-(4-aminophenoxy)phenyl]propane (BAPP), and diamino(polysiloxane) (PSX (Mw = 750)) in N-methyl-2-pyrrolidone (NMP). Their structures were analyzed by 1H-, 13C-, and 29Si-NMR spectra as well as by IR spectroscopy. The solid-state NMR spectrum was also measured to determine the spin-lattice relaxation time of the copolyimides. The observed relaxation times of both aromatic and polysiloxane segments were similar in the copolyimides having 10-30 wt % of PSX, while those in the copolyimide with 50 wt % of PSX was significantly different. This may be attributed to the morphology change due to the increase in PSX composition in the polymer backbone. The reduced viscosity of the copolyimides could be controlled by changing the monomer ratio in the feed or by adding an end-capping reagent such as phthalic anhydride into the polymerization system. The kinetic study of the solution imidization revealed that the imidization reaction obeyed second-order kinetics. The activation energy calculated for this imidization was 99.2 kJ/mol, being similar to that for the imidization of the DSDA-based aromatic polyimides. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2237-2245, 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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    Determination of empirical polarity parameters of the cellulose solvent N,N-dimethylacetamide/LiCl by means of the solvatochromic technique (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1945-1955 
    Details
    ISSN: 0887-624X
    Keywords: cellulose ; DMA/LiCl ; solvatochromism ; acidity ; basicity ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Empirical solvatochromic polarity parameters (α-, β-, and \documentclass{article}\pagestyle{empty}\begin{document}$ \pi ^* $\end{document}, AN and DN, as well as ET(30)-values) for cellulose, N,N-dimethylacetamide (DMA)/LiCl and cellulose dissolved in DMA/LiCl are presented. The following solvent polarity indicators were applied: 2,6-diphenyl-4-(2,4,6-triphenyl-1- pyridinio)-1-phenolate (1), bis(4-N,N-dimethylamino)-benzophenone (MK, 2), iron(II)-di-cyano-bis(1,10)-phenanthroline, Fe(phen)2(CN)2, (3), and copper(II)-N,N,N′,N′-tetramethyl-ethylendiamine-acetylacetonate tetraphenylborate/chloride/bromide (Cu(tmen)(acac)+ X- (4)). The solvatochromic shifts (νmax) of the indicators 1, 2, 3, and 4 adsorbed to cellulose or dissolved in DMA/LiCl reflect the corresponding properties of the surrounding, the dipolarity/polarizability (\documentclass{article}\pagestyle{empty}\begin{document}$ \pi ^* $\end{document}), the hydrogen bond donating ability or Lewis acidity (α), and the hydrogen bond accepting ability or Lewis basicity (β), respectively. Any indicator employed is well characterized (r 〉 0.97) by a linear solvation energy relationship (LSER) taking the Kamlet and Taft parameter into account: νmax(indicator) = νmax,0 + s\documentclass{article}\pagestyle{empty}\begin{document}$ \pi ^* $\end{document} + aα + bβ. Cellulose, DMA/LiCl, and the cellulose/DMA/LiCl solution approach a similar polarity with an ET(30) parameter about 52 to 53 kcal mol-1. The hypothetical interaction strength parameter (acid-base interactions, dipolar-dipolar interactions) between cellulose and DMA/LiCl are calculated by means of the individual Kamlet-Taft parameters α, β, and \documentclass{article}\pagestyle{empty}\begin{document}$ \pi ^* $\end{document} of cellulose and DMA/LiCl via a multiparameter equation. The specific chloride/cellulose interaction plays a dominant role in the cellulose solvent DMA/LiCl. Comparison of the polarity parameters of DMA/LiCl with the polarity parameters of other mixtures - such as N,N-dimethyl- formamide/LiCl, DMA/NaCl, or DMA/LiBr - are presented as well. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1945-1955, 1998
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    Synthesis and properties of new soluble aromatic polybenzoxazoles from 4,4′-diamino-3,3′-dihydroxytriphenylamines and aromatic dicarboxylic acids (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1987-1994 
    Details
    ISSN: 0887-624X
    Keywords: triphenylamine-based bis(o-aminophenol)s ; aromatic polybenzoxazoles ; solubility ; thermal behavior ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two new triphenylamine-based bis (o-aminophenol) monomers, 4,4′-diamino-3,3′-dihydroxytriphenylamines, were successfully synthesized by the cesium fluoride-mediated condensation of 2-(benzyloxy)-4-fluoronitrobenzene with aniline derivatives, followed by simultaneous deprotection and reduction. Aromatic polybenzoxazoles having inherent viscosities of 0.58-1.05 dL/g were obtained by the low-temperature solution polycondensation of the bis(aminophenol)s with various aromatic dicarboxylic acid chlorides and the subsequent thermal cyclodehydration of the resultant poly(hydroxyamide)s. All the polybenzoxazoles were amorphous, and most of them were soluble in organic solvents such as m-cresol and o-chlorophenol. Flexible and tough films of polybenzoxazoles could be cast from the DMAc solutions of some aromatic poly(hydroxyamide)s, followed by thermal cyclodehydration. The glass transition temperatures and 10% weight loss temperatures of the polybenzoxazoles under nitrogen were in the range of 262-327 and 610-640°C, respectively. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1987-1994, 1998
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    Asymmetric anionic polymerization of (2-fluorophenyl)(4-fluorophenyl)(2-pyridyl)methyl methacrylate leading to a helical polymer (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2013-2019 
    Details
    ISSN: 0887-624X
    Keywords: asymmetric polymerization ; anionic polymerization ; (2-fluorophenyl)(4-fluorophenyl)(2-pyridyl) methyl methacrylate ; optically active polymer ; helix ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A novel racemic methacrylate, (2-fluorophenyl)(4-fluorophenyl)(2-pyridyl)-methyl methacrylate1 (2F4F2PyMA), was synthesized and polymerized with chiral complexes of N,N′-diphenylethylenediamine monolithium amide (DPEDA-Li) with (-)-sparteine (Sp), (2S, 3S)-(+)-2,3-dimethoxy-1,4-bis(dimethylamino)butane (DDB), and (S)-(+)-1-(2-pyrrolidinylmethyl)pyrrolidine (PMP) in toluene at -78°C. The monomer showed higher resistance against methanolysis compared with triphenylmethyl methacrylate (TrMA) and several other analogues. In the asymmetric anionic polymerization of 2F4F2PyMA, PMP was found to be a more effective chiral ligand than DDB and Sp and gave quantitatively an optically active polymer with nearly perfect isotacticity. Enantiomer selection was observed in the polymerization of racemic 2F4F2PyMA with the chiral lithium complexes. Chiral recognition ability of the optically active poly(2F4F2PyMA) was examined by an enantioselective adsorption experiment. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2013-2019, 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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    Poly(ketomalonate) by catalytic oxidation of glycerol(4)anionic polymerization (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 195-205 
    Details
    ISSN: 0887-624X
    Keywords: tartronic acid ; ketomalonic acid ; polyether ; glycerol ; oxidation ; carbanion ; anionic polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The anionic polymerization of ketomalonic acid disodium salt via a ketone carbonyl group, initiated by the in situ generation of the carbanion of tartronic acid disodium salt, was observed in the preparation of tartronic acid disodium salt by catalytic oxidation of glycerol in a basic aqueous solution using a fixed-bed reactor packed with palladium based catalyst. Model reactions using authentic reagents of tartronic acid and ketomalonic acid demonstrated the anionic polymerization of ketomalonic acid disodium salt. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 195-205, 1998
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    A simple method for the anionic polymerization of α-carbonyl acids in water (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 189-193 
    Details
    ISSN: 0887-624X
    Keywords: ketomalonic acid ; glyoxylic acid ; pyruvic acid ; carbanion ; polyether ; tartronic acid ; anionic polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Anionic polymerization of α-carbonyl acids such as ketomalonic acid, glyoxylic acid, and pyruvic acid, via carbonyl group to form the corresponding polyether in basic aqueous media, was presented. Cogeneration of carbonyl form of monomer and the carbanion of tartronic acid disodium salt was essential for the anionic polymerization. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 189-193, 1998
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    Polymerization of acrylamide in the presence of ultrasound and peroxomonosulfate (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2715-2719 
    Details
    ISSN: 0887-624X
    Keywords: polymerization ; acrylamide ; peroxomonosulfate ; ultrasound ; mechanism ; rate parameters ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymerization of acrylamide (M) in the presence of ultrasound and peroxomonosulfate (PMS) was carried out for the first time for various concentration ranges of monomer and initiator and various temperatures at a constant frequency of 1 Mhz. The rate of polymerization Rp was found to increase with increase in the concentration of monomer and initiator and found to depend on [M] and [PMS]1/2. The rate of disappearance of initiator (-d[PMS]/dt) was also followed simultaneously under the experimental conditions and found to increase linearly with increase in [PMS]. A probable reaction mechanism was proposed on the basis of the observed results, and the individual rate constant were evaluated. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2715-2719, 1998
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    Synthesis and characterization of chiral polyamides derived from glycine and (S)-5-amino-4-methoxypentanoic acid (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2741-2748 
    Details
    ISSN: 0887-624X
    Keywords: stereoregular polymers ; chiral polyamides ; ω-amino acids ; glycine ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Stereoregular, enantiomerically pure, chiral polyamides of the -AB- type, containing a natural (glycine) and a synthetic [(S)-5-amino-4-methoxypentanoic acid (AMP)] component have been prepared by the active ester polycondensation method. Thus, polyamide 7 was obtained by polycondensation of the conveniently activated H2NGly-AMPCO2R unit (6). In this reaction, 7 appeared accompanied by a considerable amount of cyclic (Gly-AMP)2 (8), which makes the isolation and purification of 7 difficult. The formation of cyclic byproducts could be avoided by preparing and polymerizing the oligoamide H2NGly-AMP-AMPCO2R (11), which has the terminal carboxyl group activated as the pentachlorophenyl ester. The resulting polyamide (12) was obtained in 85% yield and free of macrolactams, such as 8. The new polyamides 7 and 12 were characterized by elemental analysis and infrared and 1H- and 13C-nuclear magnetic resonance spectroscopies. Thermal studies revealed that 12 is crystalline and yields films with spherulitic texture by slow evaporation of formic acid solutions. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2741-2748, 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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    Epoxidation of bacterial polyesters with unsaturated side chains. II. Rate of epoxidation and polymer properties (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2381-2387 
    Details
    ISSN: 0887-624X
    Keywords: bacterial polyesters ; epoxidation of polyesters ; polyhydroxyalkanoates ; crosslinking polyesters ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(3-hydroxyoctanoate-co-3-hydroxy-10-undecenoate)s (PHOUs) with controlled amounts of unsaturated repeating units were epoxidized to various extents with m-chloroperbenzoic acid (MCPBA) in homogeneous solution. The epoxidation reaction was second order, with an initial rate constant of 1.1 × 10-3Lmol-1.s-1 at 20°C, regardless of the unsaturated unit content in PHOU. No substantial change in either molecular weight or molecular weight distribution occurred as a result of epoxidation, but the melt transition temperature and enthalpy of melting both decreased as the unsaturated groups were increasingly converted into epoxide groups. In contrast, the glass transition temperature (Tg) increased by approximately 0.25°C for each 1 mol % of epoxidation, irrespective of the composition of the PHOU. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2381-2387, 1998
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    Sucrose-based epoxy monomers and their reactions with diethylenetriamine (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2397-2413 
    Details
    ISSN: 0887-624X
    Keywords: epoxy allyl sucroses ; epoxy crotyl sucroses ; sucrose-based epoxy monomers ; thermosets ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two sets of sucrose-based epoxy monomers, namely, epoxy allyl sucroses (EAS), and epoxy crotyl sucroses (ECS), were prepared by epoxidation of octa-O-allyl and octa-O-crotyl sucroses (OAS and OCS, respectively). Synthetic and structural characterization studies showed that the new epoxy monomers were mixtures of structural isomers and diastereoisomers that contained varying numbers of epoxy groups per sucrose. EAS and ECS can be tailored to contain an average of one to eight epoxy groups per sucrose. Quantitative 13C-NMR spectrometry and titrimetry were used independently to confirm the average number of epoxy groups per sucrose. Sucrose-based epoxy monomers were cured with diethylenetriamine (DETA) in a differential scanning calorimeter (DSC), and their curing characteristics were compared with those of diglycidyl ether of bisphenol A (DGEBA) and diepoxycrotyl ether of bisphenol A (DECEBA). EAS and DGEBA cured at 100 to 125°C and exhibited a heat of cure of about 108.8 kJ per mol epoxy. ECS and DECEBA cured at 150 and 171°C, respectively, and exhibited a heat of cure of about 83.7 kJ per mol epoxy. Depending upon the degree of epoxidation (average number of epoxy groups per sucrose) and the concentration of DETA, glass transition temperatures (Tgs) of cured EAS varied from -17 to 72°C. DETA-cured ECS containing an average of 7.3 epoxy groups per sucrose (ECS-7.3) showed no DSC glass transition between -140 and 220°C when the ratio of amine (NH) to epoxy group was 1:1 and 1.5:1. Maximum Tgs obtained for DETA-cured DGEBA and DECEBA polymers were 134 and 106°C, respectively. DETA-cured bisphenol A-based epoxy polymers degraded at about 340°C, as observed by thermogravimetric analysis (TGA). DETA-cured sucrose-based epoxy polymers degraded at about 320°C. Sucrose-based epoxies cured with DETA were found to bind aluminum, glass, and steel. Comparative lap shear tests (ASTM D1002-94) showed that DETA-cured epoxy allyl sucroses with an average of 3.2 epoxy groups per sucrose (EAS-3.2) generated a flexible adhesive comparable in bond strength to DGEBA. However, DETA-cured ECS-7.3 outperformed the bonding characteristics of both DGEBA and EAS-3.2. All sucrose-based epoxy polymers were crosslinked and insoluble in water, N,N-dimethylformamide, tetrahydrofuran, acetone, and dichloromethane. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2397-2413, 1998
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    Effect of dose rate on emulsion and microemulsion polymerization of styrene (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 257-262 
    Details
    ISSN: 0887-624X
    Keywords: nucleation mechanism ; emulsion polymerization ; microemulsion polymerization ; irradiation polymerization ; styrene ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Emulsion and microemulsion polymerization of styrene were initiated with a gamma ray to study the effect of dose rate on polymerization. In both systems, there is an apparent plateau of polymerization rate in the curve of reaction rate vs. conversion. It was shown that emulsion polymerization conformed to the Smith-Ewart theory very well. Changing the dose rate in interval 2 had no great influence on polymerization rate, but it changed the average lifetime of radicals in polymer particles and affected the molecular weight of polymer produced. For microemulsion polymerization it was assumed that in the plateau it is the number of growing polymer particles being kept constant, not the number of polymer particles. When the dose rate was changed while the polymerization came into the constant period, the polymerization rate and the molecular weight of the polymer varied with the dose rate. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 257-262, 1998
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    Physical properties and structure of a poly(styrene-co-butadiene) rubber/poly(acrylonitrile-co-butadiene) rubber latex mixture film (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2493-2501 
    Details
    ISSN: 0887-624X
    Keywords: latex ; poly(styrene-co-butadiene&) ; rubber (SBR) ; poly(acrylonitrile-co-butadiene&) ; rubber (NBR) ; modulus ; phase continuity ; tensile strength ; elongation at breakpoint ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The physical properties and the structure of a poly(styrene-co-butadiene) rubber (SBR) and poly(acrylonitrile-co-butadiene) rubber (NBR) latex mixture film are studied in relation to the composition of SBR/NBR for optimization as the precursor of a polymer electrolyte. The composition of SBR50/NBR50 is most suitable in terms of mechanical strength and ionic conductivity. The relationship between the mechanical strength and the structure is analyzed using a simple equivalent mechanical model modified from the Takayanagi model. Our model gives better agreement with experimental results and extends the range of validity of the model to the cocontinuous phase type morphologies. It is possible to estimate the mechanical strength from the continuity of the mechanical supporting phase, calculated from the mechanical model. The tensile properties are found to be strongly affected by the fragile component. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2493-2501, 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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    Light-stabilization of polymeric materials by grafted UV-cured coatings (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2571-2580 
    Details
    ISSN: 0887-624X
    Keywords: UV curing ; grafting ; photostabilization ; acrylates ; adhesion ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The weathering resistance of organic materials has been substantially increased by protecting their surface with a photocured coating containing both a UV absorber (UVA) and a radical scavenger (HALS). A kinetic study by real-time IR spectroscopy has shown that HALS have no effect on the cure rate, whereas UV absorbers slow down the cure process, due to their radiation inner filter effect. 3D analysis of the depth of cure profile revealed an incomplete cure at the coating/substrate interface, leading to adhesion failure. To prevent this detrimental effect, the UV-cured coating was photochemically grafted onto the substrate. The polymer material was first coated with a thin layer of a benzophenone solution in a diacrylate monomer. Polymer radicals, generated by hydrogen abstraction from the substrate by the excited benzophenone molecules, effectively initiate the polymerization of the acrylate functions, thus ensuring a chemical bonding between the coating and the substrate. The grafting reaction was characterized by ATR spectroscopy analysis and by surface energy measurements. Excellent adhesion was achieved by applying to the treated substrate a photocurable acrylate coating, containing the light stabilizers, because of the copolymerization reaction taking place with the unreacted acrylate double bonds of the base coat, upon UV exposure. The efficiency of this on-line stabilization process has been demonstrated on poly(vinyl chloride) that was made eight times more resistant to accelerated weathering. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2571-2580, 1998
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    Synthesis of triblock copolymers - (polyA-poly butadiene-polyA) - via metathesis polymerization (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2601-2610 
    Details
    ISSN: 0887-624X
    Keywords: triblock copolymers ; hydroxyl-terminated polybutadiene ; metathesis polymerization ; ring-opening metathesis polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of triblock copolymers of the type A-B-A were synthesized using tungsten chloride-anchored hydroxyl-terminated polybutadiene (HTPBD) catalyst. Monomers like phenylacetylene (PA), norbornene (NBE), cyclooctadiene (COD), and cyclopentene (CP) were polymerized via metathesis pathway using this catalyst. The efficiency of this anchored catalyst in producing A-B-A triblock copolymers was explored and compared under the same experimental conditions like solvent system and reaction temperature. This anchored catalyst upon reaction with PA produced polyPA-block-polyBD-block-polyPA in high yield and with low polydispersity (pdi) compared to HTPBD. The formation of the triblock copolymers by this method was evinced by NMR, TGA, and GPC data as well as by delinking and inverse addition studies. All the cycloalkenes polymerized via ring-opening metathesis polymerization (ROMP) with the catalyst and yielded triblock copolymers. The mode of synthesis of triblocks could be construed as switching the mechanism of polymerization from radical to olefin metathesis. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2601-2610, 1998
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    Seeded microemulsion polymerization of butyl acrylate (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2631-2635 
    Details
    ISSN: 0887-624X
    Keywords: microemulsion polymerization ; seeded polymerization ; butyl acrylate ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The seeded microemulsion polymerization of butyl acrylate was studied with γ-rays. The hydrodynamic diameter and its distribution of polymer particles in the seeded microemulsion before and after polymerization were determined with photon correlation spectroscopy (PCS). Though there were micelles in the microemulsion, it was found that new particle formation could be ignored during polymerization. The polymerization kinetics of the seeded microemulsion was investigated. The polymerization rate increases with the dose rate and added monomer content and decreases with the seed fraction. It was completely different from that for seeded emulsion polymerization. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2631-2635, 1998
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    Analysis of microstructure of ethylene-1-hexene copolymer prepared over thermally pretreated MgCl2/THF/TiCl4bimetallic catalyst (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 291-300 
    Details
    ISSN: 0887-624X
    Keywords: olefin polymerization ; temperature rising elution fractionation ; ethylene-1-hexene copolymer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermally pretreated catalysts were prepared by heating MgCl2/THF/TiCl4 (TT-0) at 80°C for 5 min (TT-1) and 60 min (TT-2), and at 108°C for 5 min (TT-3) and 60 min (TT-4). Ethylene-1-hexene copolymers were prepared with these catalysts. The TT-1 catalyst produced more blocky and higher 1-hexene content polymer than TT-0, 2, 3, and 4. Temperature rising elution fractionation (TREF) analysis was used to investigate the chemical composition distribution of the ethylene-1-hexene copolymer, exhibiting bimodal distribution for TT-0 and trimodal for TT-1, 2, 3, and 4. A portion of higher hexene content of the copolymer markedly increased when the copolymerization was performed with TT-1, indicating that copolymerization active sites were newly generated. Portion of homopolyethylene increased drastically when the copolymerization was performed with TT-4, indicating that ethylene homopolymerization active sites were increased. Gel permeation chromatography (GPC) also revealed that three kinds of active sites existed on the catalyst. 13C-NMR spectrum of each fraction after TREF analysis suggested that the isospecific active site could polymerize 1-hexene well, resulting in random and alternating copolymers. A scheme for generation of the active site and change of its nature during thermal treatment of bimetallic complex catalyst is proposed. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 291-300, 1998
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    Synthesis and thermal analysis of branched and “kinked” poly(ethylene terephthalate) (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 309-317 
    Details
    ISSN: 0887-624X
    Keywords: thermal analysis ; branched poly(ethylene terephthalate) ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(ethylene terephthalate) (PET) was synthesized by self-condensation of bis-(2-hydroxyethyl) terephthalate (BHET). Copolymerization of BHET with ethyl, bis-3,5-(2-hydroxyethoxy) benzoate (EBHEB) and ethyl, 3-(2-hydroxyethoxy) benzoate (E3HEB) yielded copolymers that contain varying amounts of branching and kinks, respectively. Copolymers of BHET with ethyl, 4-(2-hydroxyethoxy) benzoate (E4HEB), in which only the backbone symmetry is broken but without disruption of the linearity, were also prepared for comparison. The composition of the copolymers were established from their 1H-NMR spectra. The intrinsic viscosity of all the copolymers indicated that they were of reasonably high molecular weights. The thermal analysis of the copolymers using DSC showed that both the melting temperatures (Tm) and the percent crystallinity (as seen from the enthalpies of melting) (ΔHm) decreased with increasing comonomer (defect concentration) content, although their glass transition temperatures (Tg) were less affected. This effect was found to be most pronounced in the case of branching, while the effects of kinks and linear disruptions, on both Tm and ΔHm, were found to be similar. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 309-317, 1998
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    Profile of oxidation in irradiated polyethylene (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 329-339 
    Details
    ISSN: 0887-624X
    Keywords: ultrahigh molecular weight polyethylene (UHMWPE) ; radiation sterilization ; orthopedic prosthesis ; subsurface oxidation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Following gamma irradiation in air which causes bond scission and yields large concentrations of peroxy radicals, maximum oxidation and an increase in crystallinity occurs on the surface of ultrahigh molecular weight polyethylene. Here, bimolecular reactions of peroxy radicals generate carbonyls, mostly ketones. On the polymer surface, peroxy radicals continue to react over time periods of years to generate carbonyls and chain scission. Peroxy radicals in the interior of the polymer abstract hydrogens and form hydroperoxides, inducing chain reactions and a slow but continue increase of ketone. Within the polymer sample, to a decreasing depth with increasing dose, a reduced concentration of oxygen is available to react with radiolytic radicals, so that more efficient crosslinking and a low level of hydroperoxide chain reaction occur. After long periods of time a surface maximum in carbonyl concentration is produced. Heating polyethylene in high pressures of oxygen accelerates the oxidative process. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 329-339, 1998
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    Preparation and thermal properties of thermoplastic poly(vinyl alcohol) complexes with boronic acids (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 3045-3050 
    Details
    ISSN: 0887-624X
    Keywords: poly(vinyl alcohol) ; n-butyl boronic acid ; phenyl boronic acid ; complex ; melting temperature ; spinnability ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(vinyl alcohol) (PVA) was converted into melt flowable derivatives by complexation with a small amount of n-butyl boronic acid (BBA) and phenyl boronic acid (PBA) in dimethylsulfoxide (DMSO), and their thermal properties were examined from a viewpoint of the melt spinning of the complexes. It was found that (1) the melting temperature of the PVA-boronic acid complexes decreases and their degradation temperature increases with increasing the boronic acid content; (2) no gelation occurs for the PVA complexes with BBA and PBA in DMSO; (3) PBA gives a larger melting-temperature depression for PVA than BBA, but the spinnability of the complexes with BBA is much better than that with PBA; and (4) the melt-molded PVA complex fibers can be easily regenerated into PVA fibers with hot water. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 3045-3050, 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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    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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    Internal functionalization in hyperbranched polyesters (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 3187-3192 
    Details
    ISSN: 0887-624X
    Keywords: hyperbranched polyesters ; poly(ε-caprolactone) ; 1,4,9-trioxaspiro[4.6]-9-undecanone ; macromonomers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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    Preparation and characterization of fluorine-containing aromatic condensation polymers. VI. Aromatic polybenzothiazoles from 4,4′-(hexafluoroisopropylidene)dibenzoic acid and tetrafluoroterephthalic acid and 2,5-diamino-1,4-benzenedithiol dihydrochloride (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 429-435 
    Details
    ISSN: 0887-624X
    Keywords: fluorine-containing polymers ; aromatic polybenzothiazoles ; 4,4′-(hexafluoroisopropylidene)dibenzoic acid ; tetrafluoroterephthalic acid ; 2,5-diamino-1,4-benzenedithiol ; direct polycondensation ; phosphorus pentoxide/methanesulfonic acid ; polyphosphoric acid ; high-temperature soluble polymers ; liquid crystalline polymer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two fluorine-containing aromatic polybenzothiazoles were synthesized by direct polycondensation of 4,4′-(hexafluoroisopropylidene)dibenzoic acid and tetrafluoroterephthalic acid with 2,5-diamino-1,4-benzenedithiol dihydrochloride using phosphorus pentoxide/methanesulfonic acid or polyphosphoric acid as both condensing agent and solvent. The effect of introduction of fluorine atom on the synthesis and properties of these polymers was discussed in detail. The perfluoroisopropylidene unit-containing polybenzothiazole was amorphous, and showed good solubility in organic solvents, excellent mechanical properties, and high thermal stability. The perfluoro-p-phenylene unit-containing polybenzothiazole was crystalline, and exhibited lyotropic behavior in concentrated sulfuric acid. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 429-435, 1998
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    Phthalonitrile cure reaction with aromatic diamines (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1885-1890 
    Details
    ISSN: 0887-624X
    Keywords: phthalonitrile monomer ; thermoset ; curing agent ; processability ; thermal stability ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Phthalonitrile monomers can be polymerized thermally in the presence of small amounts of curing agents into thermosetting polymers. The thermosets exhibit outstanding thermo-oxidative stability, display good mechanical properties, and offer promise as matrices for composite applications. The phthalonitrile cure reaction is typically accomplished with an aromatic diamine, 1,3-bis(3-aminophenoxy)benzene (m-APB), added in the range of 1.5-2% by weight of the monomer in the melt phase. This article addresses the cure reaction with a sulfone-containing diamine, bis[4-(4-aminophenoxy)phenyl] sulfone (p-BAPS), which shows lower volatility as determined from thermogravimetric studies (TGA) compared to m-APB at the processing temperatures typically employed for phthalonitrile cures. Rheometric studies conducted to monitor the viscosity increase during a cure reaction suggest that the cure reaction with m-APB is faster compared to the reaction with p-BAPS. Even though differences are seen in the initial cure rates, the final cured products are similar in terms of the glass transition temperatures and thermal and oxidative stabilities. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1885-1890, 1998
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    Synthesis and properties of soluble aromatic polyimides from 2,2′-bis(3,4-dicarboxyphenoxy)-1,1′-binaphthyl dianhydride and aromatic diamines (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1937-1943 
    Details
    ISSN: 0887-624X
    Keywords: 2,2′-bis(3,4-dicarboxyphenoxy)-1,1′-binaphthyl dianhydride ; aromatic polyimides ; solubility ; thermal behavior ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Aromatic tetracarboxylic dianhydride having crank and twisted noncoplanar structure, 2,2′-bis(3,4-dicarboxyphenoxy)-1,1′-binaphthyl dianhydride, was synthesized by the reaction of 4-nitrophthalonitrile with 2,2′-dihydroxy-1,1′-binaphthyl, followed by alkaline hydrolysis of the intermediate bis(ether dinitrile) and subsequent dehydration of the resulting bis(ether diacid). Binaphthyl-2,2′-diyl-containing novel aromatic polyimides having inherent viscosities up to 0.67 dL/g were obtained by the one-step polymerization process starting from the bis(ether anhydride) and various aromatic diamines. All the polyimides showed typical amorphous diffraction patterns. Most of the polyimides were readily soluble in common organic solvents such as N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), and pyridine. These aromatic polyimides had glass transition temperatures in the range of 280-350°C, depending on the nature of the diamine moiety. All polymers were stable up to 400°C, with 10% weight loss being recorded above 485°C in air. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1937-1943, 1998
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    Synthesis and characterization of ABA-type block copolymer of poly(trimethylene carbonate) with poly(ethylene glycol): Bioerodible copolymer (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 695-702 
    Details
    ISSN: 0887-624X
    Keywords: ABA-type block copolymers ; ring-opening polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: ABA-type block copolymers of poly(trimethylene carbonate) with poly(ethylene glycol) (Mn 6820), PTMC-b-PEG-b-PTMC, were synthesized by the ring-opening polymerization of 1,3-dioxan-2-one (trimethylene carbonate) in the presence of poly-(ethylene glycol) with stannous octoate catalyst, and the copolymers with various compositions were obtained. The PTMC-b-PEG-b-PTMC copolymers were characterized with Fourier transform infrared and nuclear magnetic resonance spectroscopies. The intrinsic viscosities of resulting copolymers increased with the increase of 1,3-dioxan-2-one content in feed while the molar ratio of monomer over catalyst kept constant. It has been observed that the glass transition temperature (Tg) of the PTMC segments in copolymers, recorded from differential scanning calorimetry, was dependent on the composition of copolymers. The melting temperature (Tm) of PEG blocks in copolymer was lower than that of PEG polymer, and then disappeared as the length of PTMC blocks increased. The results of dynamic contact angle measurement clearly revealed that the hydrophilicity of resulting copolymers increased greatly with the increase of PEG content in copolymers. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 695-702, 1998
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    Synthesis and ring-opening polymerization of new 1,4-anhydro-glucopyranose derivatives (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 841-850 
    Details
    ISSN: 0887-624X
    Keywords: AMGLU ; A6BMG ; A6TMG ; ring-opening polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Three new 1,4-anhydro-glucopyranose derivatives having different hydroxyl protective groups such as 1,4-anhydro-2,3,6-tri-O-methyl-α-D-glucopyranose (AMGLU), 1,4-anhydro-6-O-benzyl-2,3-di-O-methyl-α-D-glucopyranose (A6BMG), and 1,4-anhydro-2,3-di-O-methyl-6-O-trityl-α-D-glucopyranose (A6TMG) were synthesized from methyl α-D-glucopyranoside in good yields. Their polymerizability was compared with that of 1,4-anhydro-2,3,6-tri-O-benzyl-α-D-glucopyranose (ABGLU) reported previously. The trimethylated monomer, AMGLU, was polymerized by a PF5 catalyst to give 1,5-α-furanosidic polymer having number-average molecular weights (M̄n) in the range of 2.8 × 103 to 6.8 × 103. The 13C-NMR spectrum was compared with that of methylated amylose and cellulose. Other anhydro monomers, A6BMG and A6TMG, gave the corresponding 1,5-α furanosidic polymers having M̄n = 17.1 × 103 and 1.8 × 103, respectively. Thus, the substituents at the C2 and C6 positions were found to play an important role for the ring-opening polymerizability of the 1,4-anhydro-glucose monomers. In addition, debenzylation of the tribenzylated polymer gave free (1 → 5)-α-D-glucofuranan. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 841-850, 1998
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    New aromatic benzazole polymers II: Synthesis and conductivity of benzobisthiazole-co-polymers incorporated with 4-N,N-dimethylaminotriphenylamine groups (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 713-724 
    Details
    ISSN: 0887-624X
    Keywords: poly(benzobisthiazole) ; copolymers ; 4-N,N-dimethylaminotriphenylamine ; conducting polymers ; iodine doping ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New aromatic benzobisthiazole copolymers containing 10-70 mol % of 4-N,N-dimethylamino-triphenylamine functionality were prepared from the respective dinitrile or dicarboxylic acid monomers, terephthalic acid, and 2,5-diamino-1,4-benzene-dithiol dihydrochloride in polyphosphoric acid. At the first approximation, the copolymers containing 10 mol % or less of the triarylamino moieties in the polymer chains still preserve the capability to form anisotropic (nematic) solutions at 10 wt % polymer concentration. This is an important requirement for processing the copolymers into fibers and films with good to excellent mechanical properties. Films with good mechanical integrity were cast from the dilute methanesulfonic acid solutions of the copolymers under reduced pressure. They showed electrical conductivity values of the order of 10-11-10-10 S/cm in pristine state, with four to seven orders of magnitude increase upon exposure to mild oxidizing agents such as iodine vapor. On the contrary, the parent polymer, poly(p-phenylene benzobisthiazole) is an insulator with conductivity of less than 10-12 S/cm, and its conductivity does not improve at all with exposure to iodine vapor. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 713-724, 1998
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    Synthesis, liquid crystallinity, and mechanical properties of thermotropic polyquinolines (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 749-759 
    Details
    ISSN: 0887-624X
    Keywords: polyquinoline ; liquid crystalline polymer ; thermotropic ; mechanical property ; substituted polyquinoline ; flexible groups ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermotropic liquid-crystalline polyquinolines with high molecular weights, i.e., poly[2,2′-(α,ω-dioxyphenylene (or -dioxybiphenylene) alkane)-6,6′-(4,4′-dioxybiphenyl)-bis(4-phenylquinoline)]s (P-H-B1Mns or P-H-B2Mns), were synthesized by polycondensation of 4,4′-bis(4-amino-3-benzoylphenoxy)biphenyl and α,ω-bis(4-acetophenoxy (or -acetobiphenoxy))alkanes. For P-H-B1Mn series, the Tm and Ti were in the range of 129-230°C and 156-254°C, respectively, while for the P-H-B2Mn series, those were 182-275°C and 217-309°C, respectively. The introduction of both the dioxybiphenylene group and an alkylene spacer induced thermotropic liquid crystallinity in the polyquinoline, although the introduction of the alkylene spacer alone did not induce it. In addition, polyquinolines substituted with methyl, methoxy, and chloro groups exhibited larger mesophase temperature ranges as well as higher Tms and Tis than the unsubstituted ones. Tensile strengths of these thermotropic polyquinolines were considerably high in the range of 770 to 1170 kgf/cm2. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 749-759, 1998
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    Controlled free radical ring-opening polymerization and chain extension of the “living” polymer (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 761-771 
    Details
    ISSN: 0887-624X
    Keywords: ring-opening polymerization ; “living” free radical polymerization ; stable free radical ; 2-methylene-1,3-dioxepane ; 2,2,6,6-tetramethyl-1-piperidinyloxy free radical ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Free radical ring-opening polymerization of 2-methylene-1,3-dioxepane (MDP) in the presence of 2,2,6,6-tetramethyl-1-piperidinyloxy free radical (TEMPO) has been achieved to afford a chain polyester (PMDP) with di-t-butyl peroxide (DTBP) as an initiator at 125°C. The polydispersity of the polymers decreases as the concentration of TEMPO is increased. At high TEMPO concentrations, the polydispersity as low as 1.2 was obtained, which is below the theoretical lower limit for a conventional free radical polymerization. A linear relationship between the number-average molecular weight (Mn) and the monomer conversion was observed with the best-fit line passing very close to the origin of the Mn-conversion plot. The isolated and purified TEMPO-capped PMDP polymers have been employed to prepare chain extended polymers upon addition of more MDP monomer. These results are suggestive of the “living” polymerization process. A possible polymerization mechanism might involve thermal homolysis of the TEMPO-PMDP bonds followed by the addition of the monomers. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 761-771, 1998
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    Curing reaction of biphenyl epoxy resin with different phenolic functional hardeners (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 773-783 
    Details
    ISSN: 0887-624X
    Keywords: biphenyl epoxy ; hardener ; cure kinetics ; cure mechanism ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The investigation of cure kinetics and relationships between glass transition temperature and conversion of biphenyl epoxy resin (4,4′-diglycidyloxy-3,3′,5,5′-tetramethyl biphenyl) with different phenolic hardeners was performed by differential scanning calorimeter using an isothermal approach over the temperature range 120-150°C. All kinetic parameters of the curing reaction including the reaction order, activation energy, and rate constant were calculated and reported. The results indicate that the curing reaction of formulations using xylok and dicyclopentadiene type phenolic resins (DCPDP) as hardeners proceeds through a first-order kinetic mechanism, whereas the curing reaction of formulations using phenol novolac as a hardener goes through an autocatalytic kinetic mechanism. The differences of curing reaction with the change of hardener in biphenyl epoxy resin systems were explained with the relationships between Tg and reaction conversion using the DiBenedetto equation. A detailed cure mechanism in biphenyl-type epoxy resin with the different hardeners has been suggested. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 773-783, 1998
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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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    Styrene-assisted melt free radical grafting of glycidyl methacrylate onto polypropylene (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1053-1063 
    Details
    ISSN: 0887-624X
    Keywords: free radical grafting ; polypropylene ; glycidyl methacrylate ; styrene ; maleic anhydride ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The free radical grafting reactivity of glycidyl methacrylate (GMA) onto polypropylene (PP) in the molten state is low. This article shows that adding styrene as a second monomer (or comonomer) increases both the rate and yield of GMA grafting and reduces PP chain scission. The proposed mechanism is that when St is added to the PP/GMA/peroxide grafting system, St reacts first with PP macroradicals to form stable styryl macroradicals. These latter then react (or copolymerize) with GMA to form GMA grafted PP. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1053-1063, 1998
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    Synthesis and characterization of new polyamides containing adamantyl and diamantyl moieties in the main chain (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 785-792 
    Details
    ISSN: 0887-624X
    Keywords: polyamides ; adamantane ; diamantane ; synthesis ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This work synthesized a series of new polyamides by direct polycondensation of 1,3-bis[4-(4-carboxyphenoxy)phenyl]adamantane (I) with various diamines. The diacid I was synthesized from 1,3-bis(4-hydroxyphenyl)adamantane in two steps. Polyamides III were soluble in N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMAc), and pyridine. The polyamides had medium inherent viscosities of 0.30-0.55 dL/g and number-average molecular weights (Mn) of 22,000-36,000. The polyamides IIIa and IIIb had tensile strengths of 59.8 and 77.5 MPa, elongation to breakage values of 5.8 and 7.6%, and initial moduli of 1.9 and 1.8 GPa, respectively. Their glass transition temperatures were found to be 219-295°C by means of differential scanning calorimetry (DSC). Dynamic mechanical analysis (DMA) reveals that the incorporation of rigid and bulky diamantane into polyamides IIIa and IIIb leads to high glass transition temperatures (Tgs), at 299 and 286°C, respectively. The decomposition temperatures of polyamides III at a 5% weight loss ranged from 388 to 416°C in air and from 408 to 435°C in N2 atmosphere. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 785-792, 1998
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    Case studies and literature review on the estimation of copolymerization reactivity ratios (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 813-822 
    Details
    ISSN: 0887-624X
    Keywords: copolymerization reactivity ratios ; RREVM ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The enhanced features of a computer program (RREVM) for the estimation of copolymerization reactivity ratios using statistically sound techniques are illustrated with experimental and simulated case studies. In parallel, a literature review is given on the estimation of reactivity ratios. Both aspects are extensions based on the articles by Dube et al.1 and Rossignoli and Duever.2 © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 813-822, 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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    Hydrogels by atom transfer radical polymerization. I. Poly(N-vinylpyrrolidinone-g-styrene) via the macromonomer method (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 823-830 
    Details
    ISSN: 0887-624X
    Keywords: atom transfer radical polymerization ; poly(N-vinylpyrrolidinone-g-styrene) ; macromonomer method ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Atom transfer radical polymerization has been used to prepare well-defined vinyl macromonomers of polystyrene using vinyl chloroacetate as an initiator. Because styrene and vinyl chloroacetate do not copolymerize, no branching or incorporation of the initiator into the backbone was observed. Macromonomers of several molecular weights were prepared and copolymerized free radically with N-vinylpyrrolidinone in varying feed ratios in order to produce poly(NVP-g-Sty) graft copolymers. The macromonomers used were of sufficiently high molecular weight to form physical crosslinks in solvents which favor the hydrophilic NVP, such as water, which prevent the copolymer from dissolving and cause it to swell. These materials, therefore, formed hydrogels of swellabilities in water exceeding 95%, depending on the amount of styrene that was incorporated into the copolymer. Limitations of and alternatives to this method are also discussed. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 823-830, 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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    Synthesis and radical polymerization of a vinyl monomer having a sulfonylacylurea moiety and hydrolysis of the obtained polymer (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1515-1519 
    Details
    ISSN: 0887-624X
    Keywords: sulfonyl isocyanate ; acrylamide ; sulfonylurea ; radical polymerization ; hydrolysis ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The radical polymerization of N-acryloyl-N′-(p-tolylsulfonyl)urea (2), prepared easily by the reaction of p-toluenesulfonyl isocyanate with acrylamide, was carried out in DMF, DMSO, or NMP at 60°C by use of AIBN as an initiator to give a polymer 3 in a good yield. Copolymerization parameters of 2 were evaluated by the copolymerization with MMA. Polymer 3 was readily hydrolyzed in an aqueous NaOH solution (1M) at room temperature to give poly(acrylic acid). The reason for the higher activity for hydrolysis of 3 compared to an ordinary amide is discussed. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1515-1519, 1998
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    Sequence distributions versus catalyst site behavior of in situ blends of polypropylene and poly(ethylene-co-propylene) (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1527-1542 
    Details
    ISSN: 0887-624X
    Keywords: high-impact polypropylenes ; 13C-NMR ; Markovian statistics ; reactivity ratio product ; catalyst site distribution ; sequence distributions ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Sequential polymerizations of first propylene and then ethylene, propylene mixtures with the same Ziegler-Natta catalyst system produce in situ blends known as high-impact polypropylenes. Over 100 high-impact polypropylenes are characterized in terms of weight fractions and sequence distributions for isotactic polypropylene, atactic polypropylene, an amorphous ethylene propylene copolymer, and a crystalline ethylene propylene copolymer. The apparent r1r2 behaviors of the E/P copolymers suggest that the amorphous and crystalline E/P copolymers principally arise from different types of catalyst sites as opposed to originating strictly from compositional heterogeneities. The amorphous copolymers consistently have r1r2 values close to unity over a broad range of compositions, while the corresponding crystalline copolymers have apparent r1r2 values that range from 2 to over 20. An apparent r1r2 close to unity not only reflects random sequencing but also indicates a narrow compositional distribution. This r1r2 result indicates that the amorphous E/P copolymers are produced from a singular type of catalyst site. The higher r1r2 values shown by the crystalline E/P copolymers indicate broad compositional distributions that are produced by a different type or types of catalyst sites. The ratio of amorphous to crystalline ethylene, propylene copolymers is nominally around 80/20 over a broad range of impact copolymer compositions. The consistency of this result suggests that the two basic types of catalyst sites producing E/P copolymers are also in an approximate 80/20 ratio. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1527-1542, 1998
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    Optical emission diagnostics in cascade arc plasma polymerization and surface modification processes (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1583-1592 
    Details
    ISSN: 0887-624X
    Keywords: optical emission spectroscopy ; cascade arc ; surface modification ; fluorination ; plasma polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Optical Emission Spectroscopy (OES) was used to identify reactive species and their excitation states in low-temperature cascade arc plasmas of N2, CF4, C2F4, CH4, and CH3OH. In a cascade arc plasma, the plasma gas (argon or helium) was excited in the cascade arc generator and injected into a reactor in vacuum. A reactive gas was injected into the cascade arc torch (CAT) that was expanding in the reactor. What kind of species of a reactive gas, for example, nitrogen, are created in the reactor is dependent on the electronic energy levels of the plasma gas in the cascade arc plasma jet. OES revealed that no ion of nitrogen was found when argon was used as the plasma gas of which metastable species had energy less than the ionization energy of nitrogen. When helium was used, ions of nitrogen were found. While OES is a powerful tool to identify the products of the cascade arc generation (activation process), it is less useful to identify the reactive species that are responsible for surface modification of polymers and also for plasma polymerization. The plasma surface modification and plasma polymerization are deactivation processes that cannot be identified by photoemission, which is also a deactivation process. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1583-1592, 1998
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    Kinetic and ESR studies on radical copolymerization of p-tert-butoxystyrene and di-n-butyl maleate in benzene (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1449-1455 
    Details
    ISSN: 0887-624X
    Keywords: radical copolymerization ; p-t-butoxystyrene ; dibutyl maleate ; penultimate effect ; ESR ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The copolymerization of p-tert-butoxystyrene (TBOSt) (M1) and di-n-butyl maleate (DBM) (M2) with dimethyl 2,2′-azobisisobutyrate (MAIB) in benzene at 60°C was studied kinetically and by means of ESR spectroscopy. The monomer reactivity ratios were determined to be r1 = 2.3 and r2 = 0 by a curve-fitting method. The copolymerization system was found to involve ESR-observable propagating polymer radicals under practical copolymerization conditions. The apparent rate constants of propagation (kp) and termination (kt) at different feed compositions were determined by ESR. From the relationship of kp and f1 (f1 = [M1]/([M1] + [M2])) based on a penultimate model, the rate constants of five propagations of copolymerization were evaluated as follows; k111 = 140 L/mol s, k211 = 3.5 L/mol s, k112 = 61 L/mol s, k212 = 1.5 L/mol s, and k121 = 69 L/mol s. Thus, a pronounced penultimate effect was predicted in the copolymerization. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1449-1455, 1998
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    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
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    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
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    Synthesis and study of iodonium borate salts as photoinitiators (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1667-1677 
    Details
    ISSN: 0887-624X
    Keywords: photoinitiator ; iodonium borate salts ; photoinduced radical polymerization ; fluorone dye ; visible polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Iodonium butyltriphenylborate salts (A—I+—Ar′Ph3B-—R), (=Bu) were found to be more efficient than iodonium tetraphenylborate salts (R=Ph) when used as photoinitiators for the polymerization of acrylates. Relative photodecomposition rates were also different. It was found from a study of the photoreaction of iodonium borate salts with a model monomer, methyl methacrylate, that iodonium butyltriphenylborate salts simultaneously produce a butyl radical from the borate anion and an aryl radical from the iodonium cation upon irradiation. Both radicals initiate polymerization. Iodonium tetraphenylborate salts were found to release an aryl radical, but only from the iodonium cation. Iodonium borate salts exhibit strong absorption below 300 nm with a tail absorption above 400 nm. Thus, iodonium butyltriphenyl borate salts are efficient photoinitiators even when used with visible light. When a photosensitizer such as 5,7-diiodo-3-butoxy-6-fluorone is employed, iodonium butyltriphenylborate salts are rendered much more efficient for visible light photopolymerization. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1667-1677, 1998
    Additional Material: 3 Ill.
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  • 186
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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
    Additional Material: 10 Ill.
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  • 187
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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
    Additional Material: 1 Ill.
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  • 188
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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.
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  • 189
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    Chain end analysis of bisphenol A polysulfone and its relation to molecular weight (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1309-1316 
    Details
    ISSN: 0887-624X
    Keywords: polysulfone ; step polymerization ; end-capping ; end group titration ; multiple end groups ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The preparation of amine-terminated polysulfone by step polymerization of the monomers bisphenol A and dichlorodiphenyl sulfone in the presence of end-capping reagent 4-aminophenol was investigated. A persistent problem with end-capping strategy as applied to step polymerization is the presence of end groups other than those introduced by the end-capping reagent. These unintended end groups, which can persist in the polymer product even when 100% of the end-capping reagent has reacted, are associated with a proportionate decrease in polymer chain length. This situation renders quantitative analysis of a single type of end group invalid as a method for molecular weight determination. The presence of unintended end groups does not appear to correlate with a particular set of reaction conditions; unintended end groups were found to occur in polymerizations conducted under strong base conditions (NaOH), under weak base conditions (K2CO3), and with a wide range of monomer feed ratios. A scheme for unambiguous quantification of chain ends and molecular weight for end-capped polysulfone is described. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1309-1316, 1998
    Additional Material: 2 Ill.
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  • 190
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    Successful synthesis of a 1: 1 salt monomer derived from bis(4-aminophenyl) ether and pyromellitic acid for direct polycondensation to an aromatic polyimide (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1341-1344 
    Details
    ISSN: 0887-624X
    Keywords: aromatic polyimide ; direct polycondensation ; salt monomer method ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 3 Ill.
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  • 191
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    Effect of tacticity on conformation of p-tert-butylphenol acetaldehyde resins as studied by molecular simulation (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1355-1361 
    Details
    ISSN: 0887-624X
    Keywords: p-tert-butylphenol acetaldehyde resin ; tacticity ; molecular simulation ; structural stability ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: p-tert-Butylphenol acetaldehyde resins can have isotactic, syndiotactic, and atactic sequences. Structural characteristics of the p-tert-butylphenol acetaldehyde resin with different tacticities were studied using molecular mechanics and molecular dynamics. Trimer-decamer isotactic and syndiotactic resins and 12 stereoisomers of a hexamer were calculated. In the p-tert-butylphenol acetaldehyde resin, the hydroxyl groups cluster in the center of the molecule through intramolecular hydrogen bonding and the tert-butyl groups are extended out. It has been found that the energy-minimized structures of the isotactic resin are more stable than those of the syndiotactic resin by 7-17 kcal/mol. From the results of molecular dynamics at 303, 373, 474, and 573 K for 300 ps, the isotactic resin was also found to be more stable than the syndiotactic resin. For atactic resins, the closer to isotactic their structures are, the more stable they are. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1355-1361, 1998
    Additional Material: 8 Ill.
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  • 192
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    Editorial (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. VII 
    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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  • 193
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    Comparison of activities of homogeneous Ti-based catalysts in the presence of methylaluminoxane (MAO) for synthesis of syndiotactic polystyrene by UV/visible spectroscopic study (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1733-1741 
    Details
    ISSN: 0887-624X
    Keywords: homogeneous Ti-based catalyst ; methylaluminoxane ; catalytic activity ; UV/visible spectroscopy ; syndiotactic polystyrene ; polymorphic structure ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The catalytic activities in syndiospecific polymerization of styrene in hydrocarbon using homogeneous Ti-based catalysts in the presence of methylaluminoxane (MAO) were investigated through UV/visible spectroscopic analysis. A strong UV absorption band of CpTiCl3, itself, incipiently appeared at λmax = 400 nm in toluene, followed by a bathochromic shift with its remarkable decrease by the addition of MAO. The absorption band intensity at λmax = 400 nm arising from delocalization of π-electrons on the cyclopentadienyl ring decreased by methylation in the presence of MAO with regard to the mechanism for production of an active center (“cation-like”), for example, the change of the ionic nature. The intensity decrease at λmax = 400 nm was suppressed over 2000 of the [Al]/[Ti] ratio. In the case of Ti(OC4H9)4 having a σ-ligand, new and broad UV absorption bands were developed at λmax = 340 nm and 410 nm in the presence of MAO in contrast with the CpTiCl3/MAO system. Comparison between the relative absorption intensities at λmax = 340 nm and 410 nm led to the determination of a maximum catalytic activity of Ti(OC4H9)4 in the presence of MAO related to the polymerization yield. The maximum polymerization yield was observed with regard to the relative maximum value of the absorption intensity at λmax = 410 nm with the [Al]/[Ti] ratio (500). From observation for polymorphism of the final products via differential scanning calorimetric analysis (DSC), the thermally unstable β-form seemed to be produced by the CpTiCl3/MAO system independent of the MAO concentration, the Ti(OC4H9)4/MAO system produced a thermally stable α-form in the low MAO concentration (up to 100 of the [Al]/[Ti] ratio), and a mixture of α- and/or β-forms over 200 of the [Al]/[Ti] ratio under our experimental conditions. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1733-1741, 1998
    Additional Material: 9 Ill.
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  • 194
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    Synthesis of isotactic polystyrene with a rare-earth catalyst (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1773-1778 
    Details
    ISSN: 0887-624X
    Keywords: rare-earth coordination catalyst ; styrene ; isotactic polystyrene ; neodymium ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymerization of styrene with the neodymium phosphonate Nd(P507)/H2O/Al(i-Bu)3 catalytic system has been examined. The polymer obtained was separated into a soluble and an insoluble fraction by 2-butanone extraction. 13C-NMR spectra indicate that the insoluble fraction is isotactic polystyrene and the soluble one is syndiotactic-rich atactic polystyrene. The polymerization features are described and discussed. The optimum conditions for the polymerization are as follows: [Nd] = (3.5-5.0) × 10-2 mol/L; [styrene] = 5 mol/L; [Al]/[Nd] = 6-8 mol/mol; [H2O]/[Al] = 0.05-0.08 mol/mol; polymerization temperature around 70°C. The percent yield of isotactic polystyrene (IY) is markedly affected by catalyst aging temperature. With increase of the aging temperature from 40 to 70°C, IY increases from 9% to 48%. Using AlEt3 and Al(i-Bu)2H instead of Al(i-Bu)3 decreases the yield of isotactic polystyrene. Different neodymium compounds give the following activity order: Nd(P507)3 〉 Nd(P204)3 〉 Nd(OPri)3 〉 NdCl3 + C2H5OH 〉 Nd(naph)3. With Nd(naph)3 as catalyst, only atactic polystyrene is obtained. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1773-1778, 1998
    Additional Material: 6 Ill.
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  • 195
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    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
    Additional Material: 6 Ill.
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  • 196
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    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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  • 197
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    Synthesis and reactions of a poly(methacrylate) from an optically active amino alcohol (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 1981-1986 
    Details
    ISSN: 0887-624X
    Keywords: synthesis ; radical polymerization ; (L)-phenylalaninol ; methacrylate ; cleavage ; optically active polymeric amine ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and radical polymerization of a novel optically active methacrylate, (S)-2-tert-butoxycarbonylamino-3-phenylpropyl methacrylate (MA-F-BOC), were examined. MA-F-BOC was synthesized from methacrylic acid and N-protected (L)-phenylalaninol. Radical polymerization of MA-F-BOC quantitatively afforded the corresponding polymethacrylate with a relatively high molecular weight. Radical copolymerizations of MA-F-BOC were carried out with styrene and acrylamide to afford the copolymers. Radical polymerization of MA-F-BOC in the presence of n-butanethiol afforded the oligomers, whose degrees of polymerizations were 3.3-8.0. The BOC group was completely cloven with HBr to afford the corresponding optically active polymeric amine quantitatively. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 1981-1986, 1998
    Additional Material: 3 Tab.
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  • 198
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    Syntheses and thermostabilities of N-[4-(N′-substituted aminocarbonyl)phenyl]maleimide polymers (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2001-2012 
    Details
    ISSN: 0887-624X
    Keywords: N-Substituted maleimide ; monomer reactivity ratios ; Q and e values ; thermal stability ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Three types of novel N-[4-(N′-substituted aminocarbonyl)phenyl] maleimide (RPhMI: N-substituent (R) = phenyl, cyclohexyl, and cyclododecyl) were synthesized and homopolymerized under several conditions. In the copolymerizations of RPhMI (M1) with styrene (ST; M2) or methyl methacrylate (MMA; M2), monomer reactivity ratios and Alfrey-Price Q, e values were determined. All homopolymers decomposed without softening and melting points. The initial degradation temperatures (Td) of poly(RPhMI)s were over 320°C. The glass transition temperatures (Tg) of RPhMI copolymers were much higher than those of N-phenylmaleimide (PhMI)-ST, PhMI-MMA, N-cyclohexylmaleimide (CHMI)-ST, and CHMI-MMA copolymers. Thermal stability of the terpolymers of RPhMI with ST and acrylonitrile (AN) was higher than that of ST-AN copolymers, i.e., AS resin. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2001-2012, 1998
    Additional Material: 12 Ill.
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  • 199
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    Plasma polymerization of fluoromethanes (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2043-2050 
    Details
    ISSN: 0887-624X
    Keywords: plasma polymerization ; fluoromethanes ; X-ray photoelectron spectroscopy ; glow discharge emission spectroscopy ; F/H ratio ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Methane and fluoromethanes (CHnF4-n, 1 ≤ n ≤ 3) were subjected to an rf glow discharge plasma. All the fluoromethanes (including methane) polymerized in the plasma and formed thin films. The deposition rate of the fluoromethanes depended on their monomer structure: CH2F2, of which the F/H ratio is unity, showed the greatest deposition rate. The elimination of H and F atoms as H - F was found to be a key factor for the polymerization of fluoromethanes. The chemical composition of the polymerized film, measured with X-ray photoelectron spectroscopy and glow discharge emission spectroscopy, was also found to be strongly dependent on monomer structure. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2043-2050, 1998
    Additional Material: 6 Ill.
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  • 200
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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
    Additional Material: 12 Ill.
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