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  • 1980-1984  (2,657)
  • 1970-1974  (2,547)
  • 1830-1839
  • Physics  (5,204)
  • 1
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1065-1076 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Various phosphorus-containing polyimides were prepared by the reaction of 1-[(dialkoxyphosphinyl)methyl]-2,4- and -2,6-diaminobenzenes (1) with a tetracarboxylic dianhydride like pyromellitic dianhydride (PMDA) and benzophenone tetracarboxylic dianhydride (BTDA). In addition, copolyimides that contained approximately 3% phosphorus were prepared by the reaction of 1 and m-phenylenediamine (MPD) with the aforementioned tetracarboxylic dianhydrides. Elemental analysis, inherent viscosity, infrared (IR) spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) studies were performed to characterize the polymers. Their thermal properties were compared with those of the corresponding common polyimides. It was shown that the molecular weight and thermal stability of the polymers were reduced as the concentration of the phosphorus moieties increased. The fire-resistance of the copolyimides was evaluated by determining their limiting oxygen index (LOI) value. Copolyimides that contained about 3% phosphorus showed an LOI value approximately 30% higher, than the value of the corresponding common polyimides. In addition, a model diamic acid and diimide was synthesized by the reaction of 1-[di(2-chloroethoxyphosphinyl)methyl]-2,4- and - 2,6-diaminobenzene (DCEPD) with phthalic anhydride and characterized by elemental analysis, IR, proton nuclear magnetic (1H-NMR) spectroscopy, DSC, and TGA. The pyrolysis behavior of the model compounds was investigated by gas chromatography-mass spectrometry (GC-MS). A direct cleavage of the P—C bond and a possible rearrangement to diisocyanates occurred during their pyrolysis.
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  • 2
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1123-1130 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thin film coatings were prepared by polymerizing trifluoromethyl-substituted aromatic compounds in a glow discharge with low power levels and medium pressures. Smooth, continuous films which are adherent and insoluble in conventional solvents were produced. A significant amount of the fluorine content from the monomer was retained in the polymer. The trifluoromethyl group was not removed by the plasma conditions and appeared in the film as trifluoromethyl and difluoromethylene groups. The films were slightly less wettable than those of the unfluorinated films.
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  • 3
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1153-1177 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Asymmetric polyamides from the reaction of either optically active trans-1,2-cyclopropanedicarboxylic acid (C3) or trans-1,2-cyclohexanedicarboxylic acid (C6) with 2,7-diazaspiro[4,4]nonane(DSN) were synthesized. The possible conformations of these polymers and their model compounds in 2,2,2-trifluoroethanol (TFE), water, methanesulfonic acid (MSA), and sulfuric acid were examined by circular dichroism (CD), NMR, viscosity, and dipole moment measurements. The racemic polyamides (±)C3·(±)DSN and (±)C6·(±)DSN exist in extended forms. No intrinsic viscosity changes were observed for these two polymers in TFE and MSA. Certain viscosity and spectral changes have been observed for the optically active polyamides, although no specific ordered conformations can be assigned. The optically active diacid units incorporated into the polymer give a conformation unique from the totally extended chain. CD studies seem to evidence some conformational differences among the polyamide derived from (+)C6 diacid and the optically active DSN. By changing the solvent from TFE to MSA a blue shift of the trough was observed for (+)C6·(±)DSN, a red shift for (+)C6·(-)DSN, and an inversion of the CD spectrum for (+)C6·(+)DSN polyamides. The results of the work with (+)C6·(-)DSN in dilute acid solution suggest that the rotation around the C-N bond is a relatively low-energy process. The spectral and intrinsic viscosity data are consistent with this suggestion. No drastic spectral changes have been observed for the C3·DSN polyamides by changing the solvent from TFE to MSA. The amide group in the C3·DSN polyamide and the corresponding model compound prefer a similar conformation with the carbonyl group bisecting the cyclopropane ring. The C3·DSN polyamide seems to exist in an extended form.
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  • 4
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1515-1524 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cationic grafting of polystyrene initiated by carbon black containing the CO+ClO-4 group was investigated. The introduction of CO+ClO-4 groups onto a carbon black surface was achieved by the reaction of AgClO4 with carbon black that contained a COCI group. The latter was introduced by the reaction of carboxyl groups with SOCl2. It was found that polystyrene chains could be grown from CO+ClO-4 groups on the surface of carbon black. Moreover, polystyrene was effectively grafted from carbon black: the grafting ratio at 20°C increased to 58% as conversion increased. Furthermore, the grafting ratio and molecular weight of ungrafted polystyrene decreased with an increase in polymerization temperature. These results were explained by the fact that the increasing temperature of the polymerization caused an increase in the rate of chain transfer reaction of the growing polymer chain to the monomer. The carbon black obtained from the reaction produced a stable colloidal dispersion in a good solvent for polystyrene.
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  • 5
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1541-1550 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Radical polymerization of several alkyl allyl oxalates, including methyl allyl oxalate (MAO), ethyl allyl oxalate, propyl allyl oxalate, butyl allyl oxalate, and octyl allyl oxalate, was conducted in the evolution of carbon dioxide at elevated temperatures, and was compared with the anomalous polymerization behavior of diallyl oxalate (DAO) discussed in our earlier articleA. Matsumoto, I. Tamura, M. Yamawaki, and M. Oiwa, J. Polym. Sci. Polym. Chem. Ed., 17, 1419 (1979).. The kinetic equations for the polymerization of alkyl allyl oxalate were derived following the kinetic treatment of the DAO polymerization by further consideration of the absence of cyclization of the growing polymer radical and the effective reinitiation by alkyl radical, and were then satisfactorily applied to the polymerization of MAO, as a representative alkyl allyl oxalate. The evolution of carbon dioxide in the polymerization of alkyl allyl oxalates was enhanced with the increase of bulkiness of the alkyl substituent, as a result of steric suppression of the propagation of the growing polymer radical.
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  • 6
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 17-28 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Plasma polymers synthesized by inductively coupled RF techniques have been investigated as a function of operating parameters for the isomeric perfluorinated diazines (pyrazine, pyrimidine, and pyridazine). A combination of ESCA and microanalytical studies shows that plasma polymers are produced by rearrangement mechanisms: the C/F and C/N stoichiometric ratios are similar to those of the starting monomers over a range of operating parameters. A comparison of rates of formation of plasma polymer films reveals distinctive differences between the isomeric diazines that suggest that equilibration of valence isomers occurs on a substantially slower time scale than for isomeric fluorinated benzenes5-9 which, in general, polymerize at essentially the same rates. In contrast to the remarkably low critical surface tension of plasma polymers based on perfluorobenzenes (ca. 20 dynes cm-2), the plasma polymer films from the perfluorinated diazines which are initially hydrophobic become hydrophilic in contact with water droplets. This is attributed to the hydrolytic instability of films associated with the labilizing influence of nitrogen on nucleophilic displacement of fluoride which is a feature of the chemistry of monomers.
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  • 7
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 49-60 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Studies were conducted on grafting of acrylamide (AM) and sodium-2-acrylamido-2-methylpropane sulfonate (NaAMPS) comonomers onto dextran utilizing Ce(IV) induced initiation. The effects of reaction temperature, the Ce(IV)/dextran ratio, and the AM/NaAMPS ratio on grafting yield were investigated. The graft copolymerization behavior can be explained by exchange of the AMPS anion with one of the ligands on the Ce(IV) initiator. Oxidative modification of the dextran substrate improved the yield of graft copolymer. The dextran-g-poly(acrylamido-co-sodium-2-acrylamido-2-methylpropane sulfonate) samples prepared by this method were characterized as to copolymer composition and molecular weight utilizing elemental analysis, dilute solution viscometry, and aqueous size exclusion chromatography. Relationships of molecular weight and charge density to kinematic viscosity and salt sensitivity are discussed.
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  • 8
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 77-84 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Photoinitiated cationic polymerization by photosensitization of diphenyliodonium and triphenylsulfonium salts is shown to proceed by two distinct electron transfer process: (1) direct electron transfer from excited-state photosensitizers and (2) indirect electron transfer from photogenerated radicals. The efficiency of the former process is attributed to the instability of the reduction products (from diphenyliodonium and triphenylsulfonium salts), which dissociate in competition with undergoing energy-wastage reverse electron transfer. Amplification of photons in the production of protons (or other reactive cations) is postulated to account for the high quantum yields observed in the latter process. Potential advantages of utilizing the indirect redox process in the design of UV curable hybrid systems, which contain functionality for both radical and cationic polymerization, are noted. The results also provide evidence against the importance of triplet states of the onium salts in photoinitiator activity.
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  • 9
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 107-120 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Racemic and optically active N-carboxyanhydrides (NCA)s of 2-methyl- and cis-6-methylpipecolic acid, when subjected to polymerization conditions in solution or in bulk whether with “weak” or “strong” base initiators, resisted polymerization under all conditions tried. Instead, the NCA of 2-methylpipecolic acid gave the corresponding cyclic dipeptide and the NCA of cis-6-methylpipecolic acid formed the cyclic dipeptide derived from trans-6-methylpipecolic acid. The mechanism of dimerization of these NCA's was investigated. Evidence was provided for the proposed mechanism in which the active moiety is not a carbamate ion but an amino group. Methyl 2-methylpipecolate underwent an intermolecular SN2-type reaction upon heating, yielding equimolar quantities of methyl N-methyl-2-methylpipecolate and 2-methylpipecolic acid.
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  • 10
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 135-144 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The effect of a range of 10 organic nitriles on the radiation-induced polymerization of styrene was studied. A dose rate of 4.4 rad s-1 was used. A rate of polymerization of styrene (1.744 mol L-1 of toluene solution) of 5.0 × 10-7 mol L-1 s-1 was found. With organic nitriles present (styrene:nitrile ratio of 1:0.28) the rate of polymerization increased. Rates in the range of 5.5 × 10-7 -5.2 × 10-6 mol L-1 s-1, depending on the nitrile present, were obtained. The polymers were partially characterized and evidence of involvement of each of the nitriles in the polymer chains was revealed. The increase in rate of polymerization has been attributed to the part played by nitrile radicals in the initiation of styrene polymerization. Radical yield values [as G(nitrile radical)] were derived from the relevant rate expressions. Values ranged from 2.7 to 49.5, depending on the particular nitrile. Corresponding values of G(nitrile radical) in the range of 5.1-129.4 were obtained by the manipulation of number-average molar mass data. Values of kpkt of approximately 2 × 10-5 L mol-1 s-1 were found. Trommsdorff types of effect are absent from these systems.
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  • 11
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 213-223 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The effect of parasubstituents on the radiation chemistry of poly(α-methylstyrene) (PMS) was compared for the fluoro (PFMS), chloro (PCMS), bromo (PBMS), isopropyl (PiPMS), and methoxy (PMeOM) derivatives. Radiolysis yields, ESR spectra, and GC—MS analysis of products were obtained. PMS and PFMS have similar low radiolysis yields, products, and product distributions. Only main-chain radicals which persist to 200° were observed. PCMS has increased values of Gs, Gx, and Gr. The product analysis results suggest that the presence of chlorine contributes to the primary process by dissociative electron capture and enhances the cleavage of α-methyl group. Irradiation of PBMS caused crosslinking and yielded few volatile products. PMeOMS and PiPMS gel readily by γ-irradiation and may be useful as negative radiation resists.
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  • 12
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 225-238 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: High molecular weight polysilane copolymers which contain the units in the title were prepared in high yield by sodium coupling the corresponding organodichlorosilanes in toluene. These copolymers are highly soluble in common solvents and can be drawn into fibers or formed into films by molding or casting. They are also photoactive.
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  • 13
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 277-281 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 14
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 303-318 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Iron-ion-containing polymers were prepared by reacting atactic polyvinylpyridine with ferric chloride or ferric nitrate in methanol solution. Molar ratios of Fe3+ to 4-vinylpyridine (Fe:PVP) were 1:2, 1:6, and 1:20. Three kinds of iron center were characterized from 57Fe Mössbauer spectra recorded over a temperature range of 4.2-290 K. Infrared (IR) spectra of the samples were measured also. All samples contained amorphous hydrated ferric-oxide particles that exhibited superparamagnetic behavior at low temperatures. The size of the clusters (102-103 iron atoms per particle) was estimated from the average blocking temperatures TBav, which is sensitive to the Fe:PVP ratio. For FeCl3:PVP preparations with Fe:PVP of 1:2, 1:6, and 1:20 TBav was 37, 10, and 〈4 K, respectively. A small proportion (〈10%) of high-spin ferrous iron centers was found in most samples. A third type of signal attributable to oxygen-bridged ferric dimers was found in FeCl3-PVP preparations with Fe:PVP of 1:2 or 1:6 but not in Fe(No3)3-PVP samples. This species is probably [Cl3Fe—O—FeCl3]2-. Interactions between the polymer and the various iron centers were weak.
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  • 15
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 341-352 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Five general routes for the preparation of polyoxyethylene [generally referred to as poly(ethylene glycol) or PEG] derivatives are described. These routes are (1) nucleophilic displacements with the alkoxide of PEG, (2) nucleophilic displacement on PEG-tosylate, -mesylate, or -bromide, (3) reductive amination of PEG-aldehyde, (4) reductive amination of PEG-amine, and (5) nucleophilic displacements on the s-triazine derivatives prepared from s-triazine trichloride (cyanuric chloride) and PEG. Eighteen derivatives are prepared and potential applications to catalysis, cell purifications, and other areas are discussed briefly.
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  • 16
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 391-406 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of 6-amino-2,4-trans,trans-hexadienoic acid and various of its salts was studied in the solid state. Crystals of the hydrochloride and organic inorganic double halides with cadmium chloride, manganese (II) chloride, and iron(II) chloride were found to polymerize rapidly upon UV or γ irradiation. An erythro-diisotactic polymer is obtained in the form of extended chain crystals. The polymer behaves as an amphoteric polyelectrolyte. The kinetics and the mechanism of the polymerization as well as morphological changes during the solid state reaction are discussed.
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  • 17
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 419-428 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: ESCA and contact-angle (H2O and CH2I2) measurements are used to follow changes in the surface of poly(ethylene terephthalate) film photooxidized (254 nm radiation in O2) for varying times, followed by aging for as many as three weeks or washing with water. Photooxidation occurs uniformly throughout the outermost 50 Å of the film to give a surface stoichiometry that corresponds to C10O6.6. Oxidation produces mainly carboxyl (acid) and alcohol/phenol groups, carbonyls form after extensive treatment. Low molecular weight products formed by chain scission and oxidation are removed by washing and diffuse into the bulk when aged. Oxidized products in higher molecular weight chains are not removed by washing, but can diffuse into the polymer bulk or reorient because of their chain mobility; therefore they are directed toward the polymer bulk rather than the surface. Extended photooxidation produces a stable oxidized surface more resistant to aging changes. The results are compared with those obtained for poly(ethylene terephthalate) film oxidized in an electrical discharge.
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  • 18
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 463-473 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The absolute rate constants of propagation (kp) and of termination (kt) of N-acryloylpiperidine (NAPi) were determined by the rotating sector method in bulk; kp = 273 and kt = 1.79 × 107 L/mol s at 30°C. It was noted that kp for NAPi was 100 times smaller than that for N,N-dimethylacrylamide (DMAcAm). The absolute rate constants of cross-propagations for copolymerizations with common monomers were evaluated by combination of the kp value and the monomer reactivity ratios. Quantitative comparison of the rate constants with those of DMAcAm and poly(DMAcAm) radical shows that NAPi is as reactive as DMAcAm and the smaller kp value for NAPi is ascribable to much the lower reactivity of the poly(NAPi) radical. The large difference in reactivity of the polymer radicals is discussed in relation to the steric factor of the piperadino and the dimethylamino groups which seems to affect the capability of the carboxamide group to stabilize the polymer radical.
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  • 19
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 493-502 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Preirradiation grafting of N-vinylpyrrolidone (NVP) onto poly(tetrafluoroethylene) (PTFE) and poly(tetrafluoroethylene-hexafluoropropylene) (FEP) films was investigated. The influence of grafting parameters such as preirradiation dose, monomer concentration, and grafting temperature on the rate and grafting yield was studied. Different solvents were used for diluting the monomer and it was found that the aqueous monomer solution at a concentration of 80 wt% was suitable for this grafting system. However, the graft polymerization of NVP in benzene terminated within a short time without significant grafting yield. The dependence of the grafting rate on preirradiation dose and monomer concentration was 1.2 and 1.07 order, respectively, for grafting onto PTFE films and 1.1 and 1.2 order, respectively, for grafting onto FEP films. Arrhenius plots for grafting onto PTFE films showed a breaking point at ca. 35°C and the overall activation energies were calculated as 23.6 and 9.0 Kcal/mol below and above 35°C, respectively. For grafting onto FEP films, however, no break was observed in the Arrhenius plots; the overall activation energy was 11.9 Kcal/mol. The swelling behavior and electric resistance of the grafted materials were investigated.
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  • 20
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Several polythioesters by interfacial polycondensation of 1,4-di(mercaptomethyl)-2,3,5,6-tetramethylbenzene with oxalyl, succinyl, adipoyl, suberoyl, and sebacoyl chlorides were obtained. To determine the optimal conditions for interfacial polycondensation, the influence of the following factors on yield and value of reduced viscosity were studied: type of organic phase, concentration of hydrogen chloride acceptor, the quantitative ratio of aqueous to organic phase, molar ratio of reagents; temperature of reaction, rate of acid chloride addition, and contribution of catalyst. Thorough studies were carried out only for polycondensation of the dithiol with adipoyl and sebacoyl chlorides. The structure of all polythioesters obtained under the model conditions was determined by elementary analysis and infrared spectra. Initial decomposition temperature, mass loss in percentage at the same temperature, maximum rate of decomposition, and mass loss percentage at 100-400°C were defined by thermogravimetric analyses. Chemical resistance of the polythioesters was determined by treatment with some organic solvents, mineral acids (concentrated and 10%), and sodium hydroxide (10 and 50%). Some mechanical and electrical properties of the polythioesters obtained from dithiol and adipoyl and sebacoyl chlorides were determined. The molecular weight was not measured because of the low solubility of the polythioesters.
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  • 21
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The anionic polymerization of norbornene trisulfide initiated with sodium thiophenoxide (sodium cation solvated with dibenzo-18-crown-6 ether) was studied. Polymers with high molecular weights were obtained (Mn up to 105, osmometrically). Molecular weights calculated for living polymerization conditions (i.e., one molecule of initiator yields one macromolecule) agree well with Mn measured by osmometry. 1H-NMR, 13C-{1H}-NMR, and Raman spectra of the polymer are given. Thermodynamics of polymerization in toluene solvent is described. Enthalpy ΔHss = -(1.39 ± 0.17) kcal mol-1 and entropy ΔSss = -(7.52 ± 0.55) cal mol-1 deg-1 coefficients of polymerization were evaluated from the temperature dependence of the equilibrium monomer concentration determined dilatometrically.
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  • 22
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1141-1151 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A fire- and heat-resistant polymer was obtained by the thermal polymerization of bismaleimido-substituted 2,2-bis(anilino)-4,4,6,6-tetrakis-(4-Aminophenoxy)-cyclotriphosphazene. The thermal stabilities of the polymer were evaluated in nitrogen and in air by thermogravimetric analysis. This polymer was stable to 345°C and had char yields of 78% at 800°C in nitrogen and of 71% at 700°C in air. The structures of cyclotriphosphazene precursors and the polymer were characterized using Fourier-transform infrared and proton nuclear magnetic resonance spectroscopy.
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  • 23
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1187-1190 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 4 Ill.
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  • 24
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1197-1200 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
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  • 25
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1243-1250 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The rate of reaction of alkyl halides with aqueous sodium acetate or cyanide catalyzed by phosphonium salts supported on insoluble polystyrene resins, and rates of ion-exchange of the chloride ion in the catalysts against the acetate ion, were studied as a function of catalyst particle size, the percentage of ring substitution, the morphology of polymer support, and distance between active site and polymer backbone. Rates of 1-bromooctane or benzyl chloride with macroporous, 7-25% ring-substituted catalysts increased with increasing ring substitution. Rates with macroporous catalysts increased as a heptamethylene spacer was introduced between the active site and the polymer backbone. Rates of ion-exchange with macroporous catalysts were facilitated with increasing ring substitution or by the introduction of the spacer chain. A relation between the catalytic activity of macroporous or microporous catalysts and ion-exchange rates under triphase conditions was discussed.
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  • 26
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1251-1258 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymerization of the cyclic amide of PIII is described for the first time. The N,N-diethylamine-1,3,2-dioxaphosphorinan was shown to give living reversible polymerization with anionic initiators. Lithium and sodium derivatives were found to be inactive. 1H-, 13C-, and 31P-NMR indicated that the polymer strictly reflects the monomer structure and is formed without any isomerization, the polymer chain being $\rlap{--} ({\rm OP}\left( {{\rm NR}_{\rm 2} } \right){\rm O(CH}_{\rm 2} \rlap{--} )_3 )_n $. Initiation involves attack of the anion on the P atom. From the dependence of the equilibrium monomer concentration on temeprature ΔH1s = 1.5 ± 0.2 kcal·mol-1 and ΔS1s = 4.6 ± 0.6 cal·mol-1·°K-1.
    Additional Material: 3 Ill.
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  • 27
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The interaction of α-poly-L-lysine and ε-poly-L-lysine with methyl and ethyl orange was studied by equilibrium dialysis and spectroscopic methods. The results of the dialysis measurements indicated that the extent of binding by ε-polypeptide is substantially higher than that by α-polypeptide, despite the much greater molecular weight of the latter. This difference in binding affinity was interpreted in terms of the increased conformational adaptability of ε-polypeptide because of its highly flexible structure. Furthermore, ε-polypeptide exhibited strong cooperative binding. In addition, the effect of the successive addition of α- and ε-polypeptides on the absorption spectra of methyl and ethyl orange was investigated. The addition of α-polypeptide with a molecular weight of 400,000 produced a new absorption peak at a shorter wavelength, due to the stacked dye molecules on the polypeptide chain, whereas that of ε-polypeptide did not. From the results of spectroscopic measurements a possible mode of interaction between these two polypeptides and the small molecule is discussed.
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  • 28
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1327-1333 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Grafted PMMA was isolated by the acid hydrolysis method. Weight-average and number-average molecular weights were determined by gel permeation chromatography. The number-average molecular weight of the grafted chains was about 475,000 for amylopectin and 403,000 for amylose. The number of grafted chains (mmol) ranged from 2.4 × 10-3 to 4.6 × 10-3 for amylopectin graft copolymers and from 2.9 × 10-3 to 6.8 × 10-3 for those of amylose. These results were related to others obtained from ceric ion consumption studies. The values suggest that amylopectin, because of its complex structure, favors a higher consumption of ceric ion in homopolymerization reactions and inhibits the initiation reactions of the copolymerization.
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  • 29
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1365-1372 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The progressive dissolution of carboxylated latex particles with increasing pH was utilized to investigate the internal structure of core-shell latex particles, in comparison with that of copolymeric latex particles formed from the same monomers. The results indicated that in those latex particles which are formed when ethyl acrylate (EA) -methacrylic acid (MAA) or methyl acrylate (MA) -MAA mixture is polymerized in the presence of poly(MA-MAA) or poly(EA-MAA) seeds the shell is composed of the more hydrophilic poly(MA-MAA) molecules relatively high in MAA content and the core is composed of both poly(MA-MAA) and poly(EA-MAA) molecules, regardless of the order of the stage feed, while the copolymeric latex particles are relatively uniform from surface to center in distribution of all components except MAA. Examination of the distribution of the carboxylic groups in all of the latex particles showed their concentration to be highest at the surface and to decrease with proximity to the center in accordance with other findings reported in the literature.
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  • 30
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1409-1417 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The emulsion polymerization of styrene initiated by potassium persulfate catalyzed by Ti+3 ions was studied. Two sources of Ti+3 ions were used: the titanium trichloride and titanium sulfate. It was found that the titanium ions used in conjunction with potassium persulfate decrease both the reaction rate and the average molecular weight. An even greater drop of reaction rate was noted when chlorine anions (TiCl3) were present. The presence of these ions had a stabilizing effect on the polydispersity.
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  • 31
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1471-1479 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Mass spectroscopy was done at different temperatures on epoxylated novolac resin DEN 438 (Dow Chemical Co.) alone, and after curing with various metal(II) phthalocyanine tetraamines (MPTA). Possible modes of fragmentation are given to explain the experimental results. Gas-chromatographic/mass-spectroscopic (GC-MS) analyses of MPTA derivatives indicated the presence of only trace quantities of benzene, aniline, cyanobenzene, and orthodicyanobenzene. The GC-MS studies of the cured DEN 438 epoxy resins indicated that the mechanisms of thermal degradation are qualitatively similar, and some common features were observed in their fragmentation in an electron beam and by thermal degradation. This study is a further assessment of the utility of these phthalocyanine derivatives for curing epoxy resins to produce heat-resistant polymer systems.
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  • 32
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1507-1514 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The initiation mechanism on the radical polymerization of vinyl monomers by polyethyleneglycol (PEG-300) in aqueous solution was studied. The initiating radical species were determined by means of the spin trapping technique. They were concluded to be generated by the hydrogen atom transfer from the monomer adsorbed at the ether group of PEG-300 to the free monomer.
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  • 33
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1535-1540 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The stereospecificity of benzyl derivatives of trivalent titanium (Rn TiX3-n, where X = Cl, I, n = 1-3) in butadiene polymerization was studied. It was found that dibenzyltitaniumiodide is an efficient catalyst of the 1,4-cis-polymerization of butadiene and that tribenzyltitanium forms 1,2-units. In both cases all the titanium-benzyl bonds participated in the initiation reaction and the active sites were polymeric analogues of crotyl derivatives of Ti(III); namely, bis-π-oligobutadienyltitaniumiodide and tris-π-oligobutadienyltitanium. These sites are stable at room temperature. The nature of the active sites in the polymerization of butadiene with Ziegler's 1,4-stereo-specific systems Til4 (or Til2Cl2) + AIR3 are described.
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  • 34
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1573-1578 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: When 4-hydroxy-2,2,6,6-tetramethyl piperidinoxyl (HTMPO) is processed in polypropylene in a closed mixer, almost 50% is converted to other products during the first few minutes whilst the applied torque in the mixer is high. There is associated formation of unsaturation and this fact, in conjunction with the almost complete regeneration of nitroxyl within five minutes, suggests that the corresponding hydroxylamine (HTMPOH), which can be qualitatively identified, is the major transformation product. A study of the UV stability of PP films fabricated from polymer processed for varying times shows that UV stability is related to the quantity of the redox couple (HTMPO + HTMPOH) remaining in the polymer. This is considerably reduced by severe processing. The redox capable has almost no thermal antioxidant (oven aging) activity.
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  • 35
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1611-1621 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyamides 6.10 and 6.6 (PA* 6.10 and 6.6) containing small amounts of —N=N— units in the main chains were prepared by interfacial polycondensation between hexamethylenediamine and sebacoyl chloride or adipoyl chloride with addition of azobiscyanopentanoyl chloride. Polyamide-polystyrene block copolymers (PA-b-PSt) were then prepared by decomposition of the —N=N— units of PA*, initiating radical polymerization of styrene in m-cresol. The average PA block length of PA-b-PSt thus formed was longer than that expected from the initially present PA segments between the —N=N— units. This is probably due to recombination of PA radicals whose initiation efficiency is as low as 15%. The PSt blocks also had higher molecular weight (7000-79,000) in comparison with homopolystyrene produced from monomeric azobiscyanopentanoic acid used as an initiator due to higher viscosity of polymerization system. Variation of intrinsic viscosity and turbidimetric titration behavior along with the change in composition were also discussed.
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  • 36
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1603-1610 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of trimethylsilylacetylene was investigated by using W and Mo catalysts. Mixtures of WCl6 with appropriate organometallic cocatalysts such as n-Bu4Sn and Et3SiH at 1:1 molar ratio provided poly(trimethylsilylacetylene) in high yields. On the other hand, MoCI5 gave mainly methanol-soluble oligomers even in the presence of these cocatalysts. The polymer formed was a partly insoluble yellow powder, and the molecular weight of the soluble fraction was about 7000. The IR, 1H-NMR, and 13C-NMR spectra supported the polymer structure, (CH = CSiMe3)n. Protodesilylation of poly(trimethylsilylacetylene) afforded a new polymer containing both acetylene and trimethylsilylacetylene units.
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  • 37
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1733-1742 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Cationic oligomerization of bicyclic oxalactam, 8-oxa-6-azabicyclo[3.2.1]octan-7-one [abbreviated as BOL (1)], was carried out at 0-60°C with trifluoromethanesulfonic acid and borontrifluoride etherate as catalysts to obtain the oligomer mixture at high yield. From the structural analysis of the isolated dimer, a N-(2(e)-carbamoyltetrahydropyran-6(e)-yl)-8-oxa-6-azabicyclo[3.2.1]octan-7-one, the oligomerization proceeded through the 5C-6N scission in (1) but not through the 6N-7C (amide group) scission as generally observed in common lactams. This peculiar oligomerization must result from the protonation to the oxamide unit in the BOL molecule.
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  • 38
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1775-1782 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 8 Ill.
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  • 39
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1803-1815 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of aqueous polymerization of acrylamide with KMnO4/glycine redox pair was studied in an atmosphere of nitrogen at 35 ± 0.2°C. The rate of polymerization was found to be first power on monomer, activator, and catalyst concentration. The overall energy of activation was calculated to be 15.66 kcal/deg mol (65.54 kJ/mol) between 30 and 50°C. The effects of various additives (alcohols, neutral salts, complexing agents, addition of catalyst) were studied. The dependence of the polymerization rate on the activator and catalyst concentration was studied in DMF-water mixture also. The molecular weight of polymer was determined at various temperatures of the reaction medium.
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  • 40
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1743-1756 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Several polyamides of p-phenylenedioxydiacetic acid (PDDA) were synthesized by the low-temperature solution polycondensation techniques. Six different diamines were condensed independently with p-phenylenedioxydiacetyl chloride (PDC) in a mixture of N-methyl pyrolidone (NMP) and hexamethyl phosphoramide (HMPA). The polymers were obtained in 80-95% yield and possessed inherent viscosities in the range 0.32-0.81 dL/g. The polymers were characterized by infrared (IR) and H1-NMR spectra. The solubility, density, crystallinity, and thermal stability of the polyamides were also determined. A model diamide (MDA-1) was also synthesized from aniline and PDC to confirm the formation of polyamides from diamines.
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  • 41
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1797-1801 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The radiation degradation of viscoelastic solutions of a dialkyl monohydroxy aluminum polymer compound (AIR2OH)x is investigated. Radioactive cobalt-60 is chosen for irradiation experiments. The viscosity of the polymer in six different solvents is measured after irradiation using a capillary viscometer at room temperature (25°C). The degradation effects on both the radiation dose and the solvent used.
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  • 42
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Asymmetric selective (or stereoelective) polymerization of racemic 1,2-diphenylethyl methacrylate (DPEMA) with ethylmagnesium bromide (EtMgBr)-(-)-sparteine catalyst was studied in toluene at -78°C. In the polymerization (S) enantiomer was consumed preferentially and the enantiomeric excess of initially polymerized (S) enantiomer was consumed preferentially and the enantiomeric excess of initially polymerized DPEMA was greater than 90%. Optically pure (R) monomer was recovered at about 70% polymer yield. Poly(DPEMA) obtained with EtMgBr-(-)-sparteine complex was highly isotactic. It was found in the polymerization of optically active DPEMA that optical rotation of poly(DPEMA) was dependent on the tacticity and that isotactic and syndiotactic poly(DPEMA)s showed opposite optical rotations. Circular dichroism spectra of the optically active polymers were measured.
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  • 43
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1865-1873 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The laser-initiated polymerization of a thiol-ene photopolymerizable system was studied. The laser was operated in single- and multiple-pulse modes to generate exotherms, which were measured in a modified differential scanning calorimeter. Arrhenius plots of the polymerization, obtained by measuring polymerization exotherms at various temperatures, showed positive and negative portions. Pseudoactivation energies for the thiol-ene polymerization increased rapidly at low conversions (〈50%) of the thiol and ene chromophores. The results were comparable to those obtained from photopolymerization of multifunctional acrylate monomers.
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  • 44
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1909-1921 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: By exposure to ultraviolet and gamma radiation and by the usual methods of thermal polymerization, the stereospecific polymerization of methyl aryloxymethacrylates was carried out at different temperatures in several solvents. Triad tacticity values of the polymers obtained by free-radical and ionic routes were computed from nuclear magnetic resonance spectral data. Results of this investigation support our earlier observationSee: K. Saunders, T. Balakrishnan, R. W. Lenz, and K. Hatada, Macromolecules, 12, 392 (1979). that, under the conditions used, heterotactic content is the maximum in most of these polymers, thereby justifying the high steric effect of the bulky and polar aryloxy side chain which offers equal isotactic and syndiotactic placements.
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  • 45
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1987-1996 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cationic, ring-opening polymerization of 1,6-anhydro-3,4-di-O-benzyl-2-deoxy-β-D-arabino-hexopyranose (ABDA) (=1,6-anhydro-3,4-di-O-benzyl-2-deoxy-β-D-glucopyranose) was investigated with Lewis acid as catalyst. Phosphorus pentafluoride at -78°C caused polymerization to a highly stereoregular (1 → 6)-α-linked polysaccharide. Effects of C-2 substituent on the polymerization of 1,6-anhydro sugar are discussed. In addition, copolymerization of ABDA (M1) with 1,6-anhydro-2,3,4-tri-O-benzyl-β-D-glucopyranose (LGTBE, M2) was studied. The monomer reactivity ratios calculated by the Kelen-Tüdös method were r1 = 4.46 and r2 = 1.66. Debenzylation of the polymer produced 2-deoxy-(1 → 6)-α-D-arabino-hexopyranan in which every repeating unit contained two free hydroxyl groups.
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  • 46
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2381-2393 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The absolute rate constants for propagation (kp) and for termination (kt) of ethyl α-fluoroacrylate (EFA) were determined by means of the rotating sector method; kp = 1120 and kt = 4.8 × 108 L/mol.s at 30°C. The monomer reactivity ratios for the copolymerizations with various monomers were obtained. By combining the kp values for EFA from the present study and those for common monomers with the monomer reactivity ratios, the absolute values of the rate constants for cross-propagations were also evaluated. Reactivities of EFA and poly(EFA) radical, being compared with those of methyl acrylate and its polymer radical, were found to be little affected by the α-fluoro substitution. Poly(EFA) prepared with the radical initiator was characterized by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Although the glass transition temperature obtained by DSC for poly(EFA) resembled that of poly(ethyl α-chloroacrylate), its TGA thermogram showed fast chain de polymerization to EFA that was distinct from complicated degradation of poly(ethyl α-chloroacrylate).
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  • 47
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A polymethacrylate derivative containing uracil bases was methylated by using methyl iodide or dimethyl sulfate to give polymers containing 3-methyluracil derivatives. In the case of methylation with dimethyl sulfate, sulfonation at 5-position of the bases occurred in addition to the methylation at N-3 position. The methylated polymers thus obtained were used further for the study of polymer complex formation with polymethacrylate containing adenine base.
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  • 48
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2523-2531 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyelectrolyte submicron microcapsules were prepared by interfacial crosslinking of an aqueous salt solution of poly(ethyleneimine) and a toluene solution of brominated poly-(2,6-dimethylphenylene oxide). The two solutions were brought together and mixed by sonication. As a result, a stable emulsion was obtained, which was subsequently cast into a membrane in which the microcapsules were embedded. The salt solution contained in the microcapsules could be released under controlled conditions. The rates of release were measured. They could be controlled by applying osmotic pressures, by additional quaternization of the membrane, or by modification of the structure of the capsule wall by introduction of a surfactant.
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  • 49
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2539-2550 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A combined (chemical and infrared (IR) spectrophotometric) method is discussed for the simultaneous determination of concentrations of carboxyl (A), ketone (K), and ester (E) groups formed in the oxidation of polyethylene (PE). The IR absorptivities of these functional groups were determined by using model compounds [stearic acid, stearone, poly-(1,4-butylene sebacate)]. The integral absorption of the C=O band of polymer samples which contained several oxo groups of different types was found to be additive. This method was applied to the determination of the carboxyl, ester, and ketone content of samples oxidized at different oxygen pressures.
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  • 50
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2579-2599 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyamides and related model compounds were prepared from carboxy acids and primary amines by reacting them with triphenylphosphite in an appropriate solvent at 100°C. The reactions proceeded in the absence of organic base but were accelerated by the addition of bases such as pyridine. Nevertheless, even the powerful combination of 13C and 31P NMR failed to indicate the presence of pyridinium phosphite in the reaction mixture. In the reaction of a primary amine and carboxyl groups a detectable amount of the diphenoxy aminophosphine intermediate was observed. The end products are the amides, phenol, and diphenyl phosphite. When primary amine was not present a slow formation of a phenyl ester of the carboxylic acid was evident. All the intermediate species and the end products were formed with or without added pyridine. A mixed anhydride of carboxylic acid and phosphite was never seen. The results in this article are fundamentally the same as those in the companion article (I) for which the data were obtained at 280°C in the absence of solvent and base. However, because the reaction went quickly to completion at 280°C, the diphenoxy aminophosphine intermediate was not observed. A mechanism for the amidation in which the diphenoxy aminophosphine is an initial reaction intermediate is proposed. This species reacts with the carboxylic acid through an intramolecular substitution to give an amide. This mechanism may be valid for the high-temperature reactions as well. Several minor unclear points are indicated.
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  • 51
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2661-2666 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: ESCA has been used to investigate the composition and structural features of plasma-polymerized 2,4,6-trifluoro-1,3,5-triazine. Polymer formation was studied as a function of power and post-polymerisation treatment. All the polymer films revealed an intense peak at a binding energy of ∼290.2 eV probably arising from groups. A high sensitivity towards hydrolysis was observed resulting in substantial loss of fluorine and increase in oxygen content of the plasma polymers.
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  • 52
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2685-2697 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of chain transfer to the bifunctional initiating and transfer agents (binifers) 1,4-di(2-chloro-2-propyl)benzene (p-DCC), 1,3-di(2-chloro-2-propyl)-5-tert-butylbenzene (m-tBuDCC), and 1,3-di(2-chloro-2-propyl)-4,6-dimethylbenzene (m-DMeDCC) in the polymerization of isobutylene has been investigated. Chain transfer to monomer was shown to be absent up to -20°C in CH3Cl/n-hexane and CH2Cl2/n-hexane mixtures using the m-tBuDCC/BCl3 binifer system. Chain transfer constants (Ci) to m-tBuDCC and kt/kp ratios determined in the range from -30°C to -80°C in CH3Cl/n-hexane mixtures and pure CH3Cl solvent are reported, and the activation energy differences Etr,l - Ep and Et - Ep were calculated. Chain transfer constants to p-DCC and m-DMeDCC were determined by the use of pure CH3Cl diluent at -50°C. The chain transfer reactivity of five different inifers is discussed and compared based on CI values obtained under identical conditions, with special regard to the new, sterically hindered binifer m-DMeDCC of extraordinary reactivity.
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  • 53
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2945-2952 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Influences of microenvironment of various polyelectrolytes, i.e., ionene polymers and polyamine sulfones, on the photo- and/or thermal isomerization between the trans and cis forms of sodium m-(4-ethoxyphenylazo)benzene sulfonate (SEPS) were studied. 6,6-Ionene demonstrated larger enhancing effect on the cis-trans thermal isomerization than 3,3-ionene, which indicated that the micropolarity or the pH around the polymer is important. In the Arrhenius plots for both photo- and thermal isomerizations, deviations from the linearity were observed. In the former case, a sharp bend and the negative apparent activation energy were obtained at the high temperature. Furthermore, they were sensitively affected by the polyelectrolytes.
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  • 54
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2993-3000 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The oxidation of poly(styryl)lithium with molecular oxygen was investigated in the solid state (with and without N,N,N′, N′-tetramethylethylenediamine) in benzene (with and without N,N,N′, N′-tetramethylethylenediamine) and in benzene/tetrahydrofuran (THF) solutions. The oxidation products included the corresponding polystyrene dimer [(PS)2], the dimeric poly(styrene) peroxide (PSO2PS), poly(styrene) hydroperoxide (PSO2H), and the hydroxyl-terminated polymer (PSOH). The hithertofore unreported macroperoxide (PSO2PS) accounts for approximately 50% of the dimeric product obtained from poly(styryl)lithium oxidations in the presence of Lewis bases. The total amount of peroxide products was determined by iodometric titration in the presence of a phase-transfer catalyst, dicyclohexyl-18-crown-6. On the basis of the effect of polar additives on the amount of dimeric products, it is concluded that dimer formation in the air termination of polymeric organolithium compounds results from oxidation and not carbonation reactions.
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  • 55
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3203-3215 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reaction rate measurements show that a Michaelis-Menten model proposed earlier is inadequate to describe the full course of the polymerization of 2,6-dimethylphenol to poly(2,6-dimethyl-1,4-phenylene oxide). Modification of this model to include the effects of catalyst deactivation during the reaction and difference in reactivity between the monomer and other oligomers resulted in much greater accuracy. The kinetic constants in the modified model were influenced by reaction temperature, system composition, and method of catalyst component addition.
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  • 56
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3071-3089 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Linter cellulose, untreated and treated with boric acid, ammonium sulfamate, and guanidine sulfamate, was heated iosthermally in an imaging furnace thermal balance under a flow of helium gas to obtain kinetic parameters of the weight loss and changes in the elemental content and infrared (IR) spectra during pyrolysis. The weight, carbon, hydrogen, and oxygen losses of the untreated cellulose obey a zeroth-order reaction at an early stage and a first-order reaction at a later stage. The Arrhenius parameters for the weight and elemental losses are in agreement for both reactions. The activation energy and preexponential factor of the first-order weight loss are 185 kJ/mol and 2.0 × 1013 s-1, respectively. The carbon, hydrogen, and oxygen losses of the samples treated with boric acid and guanidine sulfamate also obey a first-order reaction at a later stage of pyrolysis. The results of the elemental and IR spectral analyses suggest that the zeroth- and first-order reactions are caused mainly by the production of levoglucosan and that an initial rapid step, especially for the treated samples, is contributed by dehydration.
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  • 57
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3189-3201 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Four closely related polyesters, with aromatic ester triads and decamethylene spacers, were prepared and characterized for their thermotropic liquid crystalline properties. Two of the polymers, which were based on linear biphenols, formed stable nematic phases, whereas one of the two based on nonlinear biphenols formed a poorly defined nematic phase; the other was not liquid crystalline. Several polymerization reactions and methods were evaluated and structure-property relationships of the polymers are discussed. The concept of “degree of liquid crystallinity” for polymers with poorly defined thermotropic behavior is considered.
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  • 58
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3225-3253 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the emulsion polymerization of methyl methacrylate at 50°C have been studied in seeded systems using both chemical initiation and γ-radiolysis initiation. Both steady-state rates and (for γ-radiolysis) the relaxation from the steady state were observed. The average number of free radicals per particle was quite high (e.g., ∼0.7 for 10-3 mol dm-3 S2O28 initiator). The data are quantitatively interpreted using a generalized Smith-Ewart-Harkins model, allowing for free radical entry, exit, biomolecular termination within the latex particles, and aqueous phase hetero-termination and re-entry. From this treatment, there results (i) the dependence of the termination rate coefficient (kt) on the weight fraction of polymer (wp), (ii) lower bounds for the dependence of the entry rate coefficient on initiator concentration, and (iii) the conclusion that most exited free radicals undergo subsequent re-entry into particles rather than hetero-termination. The results for kt(wp) are consistent with diffusion control at temperatures below the glass transition point. Comparisons are presented of the behavior of methyl methacrylate, butyl methacrylate, and styrene in emulsion polymerization systems.
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  • 59
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3309-3318 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thickening reaction of polyester resins is investigated using model compounds, diesters or polyesters of 1,2-propanediol and phthalic acid with dihydroxy or dicarboxy end groups. Soluble magnesium acetylacetonate was found to be an effective thickener, and for the first time it was possible to study a thickening reaction in homogeneous media (THF solutions). The results are compared with those obtained with MgO. The proposed mechanism supposes that the central step consists of the formation and the aggregation of magnesium carboxylates in ionic areas, with entanglement of attached polyester chains. This fits our experimental results better than the hypothesis of coordination of magnesium carboxylates by ester or hydroxyl groups of the chains2-6 or than the hypothesis of the formation of linear high molecular weight compounds.7-9
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  • 60
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3383-3391 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: To study the effect of micellar aggregation upon polymerization and polymer products, the polymerization of the micelle forming monomer allyldimethyldodecylammonium bromide (I) was investigated under both micellar and isotropic conditions. NMR spectroscopy and fluorescence quenching were employed to elucidate the structural characteristics and molecular weight of the polymer obtained by γ-ray irradiation. It was found that (I) undergoes effective polymerization in the micellar state, producing a polymer which consists of a mixture of head to tail and head to head configurations at the ratio 85/15, and has a mean molecular weight of 11,000 ± 1000 daltons.
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  • 61
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 171-183 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Dimer acid (D) modified copolyesters based on 1,4-cyclohexane dimethanol (CHDM) and either terephthalic acid (T) or trans-1,4-cyclohexane dicarboxylic acid (C) were examined. Both series produced clear, flexible materials with physical properties changing regularly with changing modifier levels. Yield stress, elongation at break, and Young's modulus showed linear correlations of log property versus volume fraction of CHDM-D segments in accord with the logarithmic rule of mixtures. Annealing the CHDM-T-based copolyesters caused little or no change in properties. Annealing the CHDM-C-based copolyesters gave similar results except for a large decrease in the modulus - the higher the dimer acid level, the larger the decrease in modulus. The density measurements, the x-ray pattern, and the dynamic mechanical analysis at 110 Hz before and after the annealing treatment supported the hypothesis that the modulus decrease resulted from domain perfection in the copolyester induced by the annealing process. Transmission electron-microscope examination of osmium tetroxide-stained films supported this hypothesis, although initial results were not repeatable.
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  • 62
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3599-3602 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 3 Ill.
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  • 63
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3617-3632 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The differential scanning calorimetry studies have shown that high-molecular linear poly(diethylsiloxane) can exist in two high-temperature polymorphs which melt at 280 and 290 K. The heats of fusion of the high-temperature polymorphs are 17 and 21 J/g, respectively. Each of the high-temperature forms arises from the corresponding low-temperature form the corresponding low-temperature form when the polymer is heated: the first at 214 K (transition heat is 28 J/g) and the second at 206 K (transition heat is 26 J/g). The mesophase formed from the molten high-temperature crystalline phases melts in a rather broad temperature range of 290 to 327 K, and the heat of this transition is 2.7 J/g. Crystallization of poly(diethylsiloxane) from the mesomorphic and the supercooled amorphous state is different. In the first case, apparently, the whole mesophase is converted to the crystalline phase and the samples have a crystallinity near 1. In the second case the crystallinity is only ca. 0.3. The temperature range in which the mesophase melts depends on the molecular weight of the polymer, presence of crosslinks and the conditions under which it has been formed, e.g., temperature.
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  • 64
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3633-3647 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The copolymerizations of acrylamide (AM) with N-(1,1-dimethyl-3-oxybutyl)acrylamide (DAAM) and with N,N-dimethylacrylamide (DMAM) have been studied. The values of r1,r2 have been determined to be 0.75 for the AM-DAAM pair and 0.86 for the AM-DMAM pair. The molecular weights of the copolymers were found to decrease with an increase in the feed composition of DAAM or DMAM. The microstructure was predicted for a wide range of feed compositions through a knowledge of reactivity ratios. These model structures are utilized for assessment of structure/dilute solution relationships reported in a subsequent paper in this series.
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  • 65
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3673-3685 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Some properties of the membranes obtained by preirradiation grafting of acrylic acid onto poly(tetrafluoroethylene-perfluorovinyl ether) copolymer (PFA) films have been investigated. The dimensional change caused by grafting and swelling behavior, water uptake, electrical conductivity, and mechanical properties of the grafted films were found to increase as the grafting proceeds. The influence of the preparation conditions (such as preirradiation dose, monomer concentration, grafting temperature, and film thickness) on those properties was studied. These properties were found to be dependent mainly on the degree of grafting regardless of grafting conditions, except at higher monomer concentration (〉40 wt %). The electric conductivity and mechanical properties for the membranes obtained at higher AAc concentrations were lower than those obtained at lower ones. Analysis by x-ray microscopy of the grafted films revealed that the grafting begins at the part close to the film surface and proceeds into the central part with progressive diffusion of monomer to give finally homogeneous distribution of the electrolytes in the whole bulk of the polymer. The membranes show good electrochemical and mechanical properties which make them acceptable for practical use as cation-exchange membranes.
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  • 66
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3739-3746 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of compounds were examined as modifiers for the high activity supported catalyst TiCl4/MgCl2-AlEt3 for isospecific propylene polymerization. The list included two aromatic acid esters, 21 various Lewis bases, and 12 alcohols. A convenient graphic method is described for comparing the performance of different modifiers by plotting experimental results in coordinates “relative activity-isotactic index” and a kinetic rationale for this evaluation is presented. Aromatic acid esters exhibit much better performance than the bulk of Lewis bases but some sterically demanding aromatic alcohols show behavior show similar to that of the esters.
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  • 67
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Silicic acid esters were prepared by the reaction of the silicic acid in tetrahydrofuran with various alcohols such as such as methanol, ethanol, 2-propanol, 1-butanol, 2-methyl-2-propanol and 1-octanol, using an esterification apparatus designed especially to allow the preparation of silicic acid esters from alcohols with low boiling points or appreciable steric hindrance. With the intent of obtaining a spinnable ester solution by condensation of silicic acid esters, the effects of the degree of esterification (DE) and alkyl group on gel time and spinnability are investigated. An increase in the DE and the size of the alkyl group led to an increase in the gel time of the esters. Esters solutions with a good spinnability were prepared from n-butyl and isopropyl esters with DEs of 40-50%. In addition, the gel permeation chromatography of condensing esters with low DEs showed a rapid increase in molecular weight. The results showed that spinnability depended on DE and the ester's alkyl group. Fibers could be formed with length of about 10-100 cm from ethyl, isopropyl, and n-butyl esters with DEs 40-50% and with length of 10 cm from octyl ester with DE 26%.
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  • 68
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 429-435 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymerization of methyl methacrylate in visible light was studied at 30°C using the isoquino-line-chlorine charge-transfer complex as the photoinitiator. Analyses of kinetic and other data indicate that the polymerization proceeds via a radical mechanism and the termination is initiator dependent. Chain termination via degradative chain (initiator) transfer appears to be significant.
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  • 69
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 453-462 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal and radiation-induced in-source and postirradiation polymerizations of N-tert-butylacrylamide and (N-tert-butylacrylamide)2-ZnCl2 complex of this monomer were studied at various temperatures. In in-source, solid-state polymerizations of monomer and complex the conversion was about 95% at 21°C in about eight days. Their postirradiation polymerizations were also studied in solid state. The conversion-time curves of these two systems show an autoacceleration as in-source polymerization. In both types of polymerization the overall rate of polymerization of complex was higher than that of pure monomer at the same polymerization temperature. In investigations of the thermal polymerization of N-tert-butylacrylamide and ZnCl2-complex it was observed that the ZnCl2-complex system can be polymerized in air in the molten and solid state. The conversion of monomer to polymer reaches limiting values in solid state in about 1 hr. The thermal polymerization of ZnCl2-complex in the molten state was also studied and 100% conversion was obtained in 30 min. The thermal polymerization of pure monomer was studied in vacuum and an appreciable amount of polymer was obtained in the molten state; however, the thermal polymerization of this monomer is negligible in solid state. In this work rates of polymerization for N-tert-butylacrylamide and (N-tert-butylacrylamide)2-ZnCl2 are compared under various experimental conditions and overall activation energies are calculated.
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 503-507 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 71
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 3905-3919 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: As previously reported, our initial investigation was concerned with the bicyclic olefins, ethylidene norbornane, and dihydrodicyclopentadiene. The former produced a skeletally rearranged γ-sultone and the latter an allylic sulfonic acid. In an attempt to further clarify the mechanisms of the sulfonation of these two models and to extend the study to models of other types of EPDM, we have now examined the sulfonation of several other model olefins. In addition to the bicyclic olefins reported previously, we have studied the sulfonation of monocyclic type II and III olefins and cyclic type I and type II olefins. The results showed that the bicyclic olefins behaved differently from their monocyclic analogs reinforcing earlier speculation as to a synchronous reaction mechanism. Exocyclics gave allylic sulfonic acids while endocyclics produced β-sultones, which is the exact reverse of what was observed for the bicyclic counterparts. Acyclic type II olefins produced “stable” β-sultones, and the influence of the sulfonating reagent on the subsequent chemistry is discussed. Type I olefins, curiously, gave a complex mixture of initial products which tended to rearrange to essentially a single thermodynamic product. The results of the investigation suggest that based on these models, each of the three major types of EPDM should have a different sulfonation mechanism.
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  • 72
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 637-644 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Coordination polymerization of olefins has become an industrially important, yet still poorly understood enterprise. The ethylene polymerization activity of (neophyl)nZrCl4-n shows a twentyfold increase from n = 4 to n = 3 and a further tenfold increase to n = 2. The heterogeneous MR4/TiCl4 catalysts (M = Ti, R = benzyl; M = Zr, R = benzyl, neophyl) have been developed. To explore the breadth of extendability, other metal chlorides (main group and transition metal) were substituted for TiCl4. Indeed, excess AlCl3 or MgCl2 and the MR4 compounds also produced ethylene polymerization catalysts. The inactivity of corresponding (neophyl)4Ti systems is attributed to sterics. The abovementioned catalysts highlight the necessity of alkyl and chloride ligands at the transition metal catalyst centers.
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  • 73
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 975-984 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The preparation of 3-aminopropylcellulose from cyanoethylcellulose is readily achieved. Reduction of the cyano groups with borane-dimethyl sulfide in tetrahydrofuran or a borane-tetrahy-drofuran complex proceeds quantitatively in 3 h to a corresponding 3-aminopropylcellulose. The presence of primary amine functions is confirmed by spectroscopy and a positive ninhydrin test; the concentration of amino substituents, as ascertained by titration, ranged from 1.2 to 6.4 meq/g. Because the derivatives are neither soluble nor excessively swollen in water, applications as ion-exchange resins or chromatographic supports can be envisioned. Treatment of 3-aminopropyl-cellulose with acetyl chloride, phenyl isocyanate, or p-toluenesulfonyl isocyanate produced 3-acetamido-, 3-(N′-phenyluredo)-, or 3-(N′-p-toluenesulfonyluredo)-N-propylcellulose. Alkylation with methyl chloride yielded a water-soluble quaternary ammonium salt.
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  • 74
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1017-1023 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Aromatic polythioamide-oxothioxoquinazolines were synthesized by the polycondensation of 2,2′-(m-phenylene)bis-1,3,4-thiadiazoline-5-thione with aromatic bis-o-amino esters. The polymerizations were carried out at 160°C in acidic media such as m-cresol, sulfolane, and polyphosphoric acid to produce polymers with reduced viscosities up to 0.5 dL/g. These polymers were soluble in polar aprotic solvents like N-methyl-2-pyrrolidone and some acidic media including m-cresol. The polythioamide-oxothioxoquinazolines showed relatively good thermal stability with 10% weight loss at 344-394°C in air.
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  • 75
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1055-1064 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Phosphorus-containing polyamides and polyesters, which had tricyclic fused rings (phenothia-phosphine rings) in the main chain, were prepared and the properties of the resulting polymers were examined. These polymers were obtained at highly reduced viscosities in satisfactory yields by the polycondensation of 2,8-dichloroformyl-10-phenylphenothiaphosphine 5,5,10-trioxide with aromatic diamines or bisphenols. The polyamides and polyesters were soluble in polar aprotic solvents such as dimethylacetamide and N-methyl-2-pyrrolidone; the polyesters were also soluble in chloroform. The polymers exhibited good heat resistance. The phenothiaphosphine-containing polyamides and polyesters self-extinguished immediately when flame was removed and were highly flame-resistant. The polyester obtained from bisphenol A showed a limiting oxygen index value of 43.5.
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  • 76
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1115-1121 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(methyl vinyl ether-alt-ammonium maleamate), when heated at up to 100°C while removing volatiles, is converted to polymer whose infrared, elemental analysis and Tg are consistent with a structure predominantly that of poly(methyl vinyl ether-alt-maleic anhydride). Maleimide comonomer units are a substantially lesser component. Evidence is presented that a part of the reaction sequence may involve hydrolysis of imide or amide.
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    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The decomposition reaction of hydrogen peroxide by Fe(III)- and Co(III)-2,9,16,23-tetracarboxyphthalocyanine supported on poly(2-vinylpyridine-CO-styrene) and the quaternized one, was studied at pH 7.0 in aqueous media. The kinetics of this reaction was also investigated at pH 7.0 by measuring the initial velocity V0 of the increasing concentration of O2 with a Warburg respirometer. The reaction proceeded according to the catalaselike mechanism. Fe(III)-2,9,16,23-tetracarboxyphthalocyanine supported on poly(2-vinylpyridine-CO-styrene) was a remarkably effective catalyst for a H2O2 decomposition reaction. The coordination sphere around the Fe(III)-phthalocyanine ring was characterized by electronic and ESR spectroscopy. Fe(III)-phthalocyanine supported on the copolymer dispersed in water was the five-coordinated, high-spin type. A typical competitive inhibition in respect of H2O2 by CN- was observed. ESR spectrum of this system showed the low spin iron(III) in the octahedral ligand field. The polymer coils hindered undesirable dimerization of metal-phthalocyanine molecules by the shielding effect.
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  • 78
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1357-1363 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The photochemical polymerization reactions of isoprene with the use of H2O2 as the photoinitiator have been studied in benzene, acetone, and tetrahydrofuran solutions. Hydrogen peroxide is photodecomposed to form hydroxyl radicals which may initiate the polymerization of isoprene with hydroxyl terminated polyisoprene as the product. Average molecular weight, microstructure, and the functionality of the hydroxyl terminated polyisoprene are determined. A suitable reaction mechanism and the polymerization rate equations are proposed. The overall activations energy is evaluated to be about 3.8 kcal/mol.
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  • 79
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1393-1407 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: p-Vinylphenylsulfonylmethyl isocyanide (1M) was synthesized starting with sodium p-styrenesulfinate via p-vinylphenylsulfonylmethylformamide (4M). Free-radical polymerization of 1M provided cross-linked insoluble polymers (1), whereas 4M provided soluble polymers, which could be converted to soluble polymer 1. Conversions of carbonyl compounds to nitriles and Schiff bases to 1,5-disubstituted imidazoles with both soluble and cross-linked polymers 1 as reagents proceeded almost as efficiently as with their low molecular weight analog. Reusability of polymer 1 was fairly good.
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  • 80
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1487-1494 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polypyromellitimides were prepared by the reaction of di(4-aminophenyl) ether (E)/di (4-aminophenyl) methane (M), and pyromellitic dianhydride in dimethylformamide, followed by thermal cyclization in a nitrogen atmosphere. Copolyimides were obtained by taking different molar ratios of diamines in the initial monomer feed. Differential scanning calorimetric, thermogravimetric analysis, and thermally stimulated current studies were carried out on these samples. It was concluded that the dielectric relaxation in these copolymers is due to trapping of the charge carriers. The dielectric relaxation parameters and activation energies were also calculated.
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  • 81
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1525-1530 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(α-methylstyrene-butadiene-α-methylstyrene) (mSBmS) was synthesized by two stages living anionic polymerization. Sodium naphthalene was used as initiator and HMPT as promoter to accelerate cross-over reactions. The microstructure and composition of mSBmS were identified by infrared and nuclear magnetic resonance spectroscopes. The domain size was roughly calculated from TEM observation. It was observed that the morphology changed with the composition. The mSBmS exhibited two Tgs, -4 and 172°C, that associated with polybutadiene and poly-α-methylstyrene, respectively. Comparing stress relaxation behaviors of mSBmS and styrene-butadienestyrene (SBS) at various temperatures, mSBmS showed a better thermal stability and degradation resistance than SBS. From the thermal gravimetric analysis, at 200°C, mSBmS gave a weight loss less than 1%, which provided a further evidence of better thermal stability of this material than of SBS.
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  • 82
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two silicon-containing acid dichlorides, bis(4-chlorocarbonylphenyl)dimethylsilane and bis(4-chlorocarbonylphenyl)diphenylsilane, were synthesized and reacted with 1,3-phenylene diamine, 1,4-phenylene diamine, 4,4′-diaminodiphenyl, 4,4′-diaminodiphenyl methane 4,4′-diaminodiphenyl ether, and 4,4′-diaminodiphenyl sulfone in the preparation of 12 structurally different high molecular weight aromatic polyamides. A low-temperature interfacial polycondensation technique was used. Most of the polyamides formed tough, transparent, flexible films and were characterized by solubility, solution viscosity, infrared spectroscopy (IR), and glass transition temperature (Tg). The thermal behavior of these aramids was studied by dynamic thermogravimetry. The effect of diamine and acid dichloride structure on the aramids properties is also discussed.
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  • 83
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New polythioesters by interfacial polycondensation of 1,4-di(mercaptomethyl)-tetramethylbenzene with phthaloyl, isophthaloyl, and terephthaloyl chlorides were obtained. To determine the optimal conditions of interfacial polycondensation the influence of the following factors on yield and value of reduced viscosity were studied: type of organic phase, the quantitative ratio of aqueous to organic phase, concentration of hydrogen chloride acceptor, molar ratio of reagents, rate of acid chloride addition, contribution of benzyltriethylammonium chloride as a catalyst, and the temperature of the reaction. The yield of all reaction products and the reduced viscosity of polythioesters which were soluble in the mixture of phenol-tetrachloroethane were found. A thorough examination was carried out only for the polycondensation of dithiol with isophthaloyl chloride. The structure of all polythioesters obtained under the model conditions was determined by elementary analysis and infrared spectra. Initial decomposition temperature and maximum rate of decomposition temperature were defined from the curves of thermogravimetric analysis. Some mechanical and electrical properties of the polythioesters were determined. The molecular weight was not measured because of the low solubility of the obtained polythioesters.
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  • 84
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1653-1660 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A Vilsmeier adduct derived from arylsulfonyl chlorides and DMF in pyridine was successfully used as a new condensating agent for the synthesis of aromatic polyesters by the direct polycondensation of aromatic dicarboxylic acids and bisphenols and also of hydroxybenzoic acids. Polymers of high molecular weights (M̄w = 78,000) with relatively narrow molecular weight distribution (M̄w/M̄n ≈ 3.0) were prepared by reacting aromatic dicarboxylic acids with the adduct in pyridine, followed by addition of bisphenols. The polycondensation was significantly affected by the amount of DMF, the nature of the arylsulfonyl chlorides, the conditions of initial reaction of the acids with the adduct, and the rate of reaction with bisphenols. The process was adaptable to the direct polycondensation of hydroxybenzoic acids, affording polymers of high molecular weight (ηinh = 1.73).
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  • 85
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1699-1705 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reason for the lower water solubility in W/O microemulsions of the styrene dimer, trans, trans-1,4-diphenyl-1,3-butadiene, in comparison with the monomer was investigated by determining the phase equilibria in the microemulsion system with pentanol as the cosurfactant and sodium dodecyl sulfate as the surfactant. The main factor for the low tolerance for water in the system was the incompatibility of the dimer with the cosurfactant and surfactant.
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  • 86
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1707-1715 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The phthalide-containing epoxy resins are synthesized and characterized in comparison with the bisphenol-A epoxy resins in terms of thermal properties. Although both resins contain comparable amounts of halogens, the resulting flame retardancy is higher in the phthalide-containing resin. The char formation upon pyrolysis is also enhanced by the phthalide functionality.
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  • 87
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1757-1773 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The placement of ionic groups within the molecular structure of a polymer produces marked modification in physical properties. A large number of studies have been performed on these ion-containing polymers, but few have focused on the effects of anion-cation interactions (i.e., counterion binding or ionization) on hydrodynamic volume, especially as the molecular structure of the solvent and nature of counterion are varied. In this study changes in hydrodynamic volume are followed through reduced viscosity measurements as a function of the abovementioned molecular parameters.The dilute solution properties of various polyelectrolytes that contain sulfonate and carboxylate groups were investigated as a function of the counterion structure, charge density, molecular weight, and solvent structure. The polymeric materials were selected because of their specific chemical structure and physical properties. In the first instance a (2-acrylamide-2 methylpropanesulfonic acid)-acrylamide-sodium vinyl sulfonate terpolymer was synthesized and subsequently neutralized with a series of bases. Viscometric measurements on these materials indicate that the nature of the cation affects the ability of the polyelectrolyte to expand its hydrodynamic volume at low polymer levels. The magnitude of the molecular expansion is shown to be due in part to the ability of the counterion to dissociate from the backbone chain, which, in turn, is directly related to the solvent structure. The changes in solution behaviour of these inomers lend support for the existence of ion pairs (i.e., site binding) and ionized moieties on the polymer chains. Measurements performed in a variety of solvent systems further confirm this interpretation. In addition, and acrylamide-sodium vinyl sulfonate copolymer was partially hydrolyzed with sodium hydroxide to study the effect of varying the charge density at a constant degree of polymerization and counterion structure. The results show that the charge density has a significant effect on the magnitude of the reduced viscosity and dilute solution behaviour. These observations, made in aqueous and nonaqueous solvents, are related to the interrelation of hydrodynamic volume, counterion concentration, and site binding. Again the controlling factor is the degree of site binding of the counterion onto the polymer backbone. Finally, we observe that the increased hydrodynamic volume affects viscosity behavior beyond the polyelectrolyte effect regime. If the average charge density on the macromolecule is relative high and/or the molecular weight is large (≥ 106) sufficient intermolecular interactions will occur to produce rapid changes in reduced viscosity.
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  • 88
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1789-1796 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Efforts to prepare triphenylsulfonium hexafluorophosphate by metathesis between commercially available “triphenylsulfonium chloride” and potassium hexafluorophosphate failed to yield the expected product but gave, instead, in approximately 50% yield, a crystalline substance with well-defined properties readily distinguishable from triphenylsulfonium hexafluorophosphate. The unexpected substance is identified as bis-[4(diphenylsulfonio)phenyl]sulfide-bis-hexafluorophosphate, for which no previous reference has been found in the literature. Its identification is based on elemental analysis, NMR, mass spectrometry, and infrared analysis. Bis-[4-(diphenylsulfonio)phenyl]sulfide-bis-hexafluorophosphate was also prepared by the reaction of benzene with sulfur monochloride in the presence of aluminum chloride and chlorine, followed by addition of potassium hexafluorophosphate. The product is an effective photonitiator for the crosslinking of epoxide resins.
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  • 89
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2083-2093 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Glow discharge polymerizations in systems of trimethoxymethylsilane, trimethoxyvinylsilane, tetramethylsilane, and trimethylvinylsilane were compared by elemental analysis, infrared (IR) spectroscopy, and ESCA to reveal effects of methoxyl, methyl, and vinyl substituents. The substituent effects appeared in the chemical composition of the polymers formed especially at low W/FM values. Methoxy groups depressed the C/Si and H/Si ratios of the polymers rather than the methyl groups, whereas vinyl groups increased the C/Si and H/Si ratios. On IR spectra the polymers formed from silanes that contained methoxy groups showed fewer absorptions due to Si—H groups and strong absorptions due to Si—OH groups. The polymers from those that contained no methoxy groups showed absorptions of Si—H groups and no absorptions of Si—OH groups. These differences in the environment of Si atoms of polymeric chains also appeared in the Si2p core level spectra, thus indicating the different fragmentation patterns of the starting materials in glow discharge.
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  • 90
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of polyethyleneimine derivatives and their oligomer models with pendant thymine or adenine bases separated by β-alanyl groups as spacers were prepared by an activated ester method. To elucidate the nature of intramolecular interaction of thymine and adenine bases ultraviolet (UV) spectrophotometric studies were undertaken for the series of compounds and the results were compared with those obtained for the corresponding oligomers without spacers. In the thymine derivatives, the nature of the intramolecular interaction resembled that of the corresponding compounds without β-alanyl units, although larger hypochromicities were found in the series with β-alanyl units. In the adenine derivatives, contrary to the corresponding thymine systems, UV hypochromicities of the compounds decreased by incorporation of the spacer group into side chains. It became evident that the intramolecular interaction of adenine bases was due to stacking neutral species, hydrogen bonding, and residual hypochromicity for the protonated species.
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  • 91
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2159-2168 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Separation of various alcohols and water through a membrane was carried out by means of a hydrogen-bonding interaction. A membrane obtained from poly(maleimide-co-acrylonitrile) was effective for a selective separation of water from aqueous alcohol solution by pervaporation technique. Spectroscopic analyses verified that this high selectivity was attributed to the hydrogen-bonding interaction between water and maleimide units in the membrane.
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  • 92
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 2197-2215 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Seeded emulsion copolymerization of an azeotropic composition of styrene (St) and an acrylinitrile (AN) comonomer mixture in polystyrene (PS) seed at different polymerization temperature of 55-75°C were investigated. The kinetic data showed a transition temperature at 65°C, above which the activation energy of polymerization is low, 6.1 Kcal/mol, compared with 9.8 Kcal/mol below it. The particle-size results and thin layer chromatographic (TLC) data showed two types of particle of different composition and morphology in the final latex system: a smaller size of (St-AN) copolymer and a larger size of core-PS and (St-AN) copolymer shell, with a zone of PS grafted (St-AN) copolymer in between. Various polymerization parameters, that is emulsifier concentration, type of seed particle and its size, and monomer/polymer ratio, were studied and their effects on particle size and particle morphology were examined. The percent of grafted core-PS was 10% below a polymerization temperature of 65°C and 40% above that temperature. By adjusting the size and number of the seed particles, monomer-polymer ratio, and emulsifier concentration conditions were established in which a final copolymer latex with “perfect” core-shell morphology was achieved.
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  • 93
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 597-604 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A kinetic study has been made on the preirradiation grafting of acrylic acid (AAc) onto poly(tetrafluoroethylene-perfluorovinyl ether) (PFA) film. The effect of grafting conditions was investigated. The dependences of the grafting rate on preirradiation dose and monomer concentration was found to be of the order of 0.5 and 1.3, respectively. The final degree of grafting was found to increase with dose and monomer concentration. However, it decreases as the grafting temperature increase. The overall activation energy for the graft polymerization was calculated from Arrhenius plots to be 5.6 kcal/mol. The activation energy for this grafting system was found to be independent of preirradiation dose used in the range from 10 to 100 kGy. The relationship between the grafting rate and film thickness gave a negative first-order dependence. The results suggest that the grafting proceeds by radical mechanism with bimolecular termination of growing chain radicals. It was reasonable concluded that this grafting proceeds from the surface to the center of film with progressive monomer diffusion through the grafted layer which swells in the monomer solution.
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  • 94
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1495-1506 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The chemical changes that accompany the crosslinking of an epoxy resin by an anhydride curing agent were followed by internal reflection spectroscopy (IRS). The crosslinking process was carried out on the surface of a germanium IRS element and the effects of various surface treatments of the germanium (humid aging, oxidation, and silane coating) on the reaction kinetics were examined. The reaction kinetics in the first 3000-4000 Å of the resin adjacent to dry, freshly polished germanium were similar to the reaction kinetics in the bulk of the resin. However, humid aging or oxidation of the germanium surface produced a local acceleration in the rate of anhydride consumption and reduced the yield of ester products. The aminosilane coating accelerated the consumption of anhydride, decreased the yield of ester, and resulted in the formation of amide groups in the interfacial region.
    Additional Material: 9 Ill.
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  • 95
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1-16 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A detailed investigation was made by ESCA of the gross structural features and chemical composition of ultrathin plasma polymer films prepared from tetrafluoropyridazine. The data reveal evidence of extensive rearrangement that accompanied polymerization and that the C:F and C:N stoichiometries of the polymer films were similar to those of the starting monomer. From an initially high contact angle with water the surfaces became completely wettable with time and this is attributed to surface hydrolysis. A comparison is made between surface and bulk compositions. Brief consideration is also given to sleeve effects.
    Additional Material: 6 Ill.
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  • 96
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 41-47 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Alternating copolymers of phenylvinyl ethyl ether (I) and phenylvinyl sec-butyl ether (II) with maleic anhydride (MAn) were prepared in bulk or in benzene solution by high-energy irradiation at dose rates of 42, 160, and 540 Gy/h, respectively. The overall energies of activation in copolymerization of I and II with MAn were 15.5 and 18.8 kJ/mol, respectively. The reaction proceeds by the free-radical mechanism and was found to be largely dependent on the bulkiness of the alkyl group. In the copolymerization of I and MAn, the molecular weight increases with conversion. By applying the model described by Shirota and co-workers, it was established that participation of charge-transfer-complex monomers increases with the increase of the total monomer concentration and with the bulkiness of the alkyl group in electron donor monomer.
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  • 97
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 69-76 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Laser flash photolysis of diphenyliodonium salts produces phenyliodinium radical cation (PhI+·), which was also generated independently by flash-induced electron transfer from iodobenzene to a phenanthrolinium salt. Apparent second-order rate constants were determined for reaction of the transient (PhI+·) with nucleophiles, including iodobenzene and cyclohexene oxide. Quantum yields of formation of acid from stationary photolysis of diphenyliodonium hexafluoroarsenate were found to be significantly higher than yields of iodobenzene. These results may be explained by facile reaction of PhI+· with PhI to yield a new iodonium salt together with a proton. High reactivity of PhI+· with cyclohexene oxide suggests that the transient may directly initiate cationic polymerization of epoxides.
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  • 98
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 85-96 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The effect of solvent in homo- and copolymerizations of methacryloyl fluoride (MAF) was investigated in various aromatic solvents. In these solvents, there is a significant effect on the rate of polymerization, on the tacticity of the resulting poly(methacryloyl fluoride), and on the copolymerization of MAF with methyl methacrylate (MMA). The equilibrium constants between MAF and aromatic solvents were determined from NMR spectroscopic measurements. These results indicated that the solvent effect on the MAF polymerization stems from changes in reactivity of MAF induced by the strong MAF-solvent interaction as well as stabilization of the MAF radical by solvents. Copolymerization of MAF with both p-methoxystyrene (MSt) and p-nitrostyrene (NSt) was also studied.
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  • 99
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Several N-substituted chloromaleimides were prepared by dehydrating the corresponding chloromaleamic acids. Treatment of chloromaleimides with allylamine or cyclopropylamine produced N-aryl-2-(allylamino)maleimides and N-aryl-2-(cyclopropylamino)maleimides, respectively. Neither the N-substituted chloromaleimides nor the N-aryl-2-(allylamino) or N-aryl-2-(cyclopropylamino)maleimides polymerized free radically or anionically. The difficulty of achieving good pi-pi overlap and stiric effects at the propagation step prevented the cyclopolymerization of the prepared 1,5-dienes.
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  • 100
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    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 159-170 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Formable silane copolymers that contain dimethylsilylene units were synthesized and characterized. These polymers have high molecular weights and appreciable solubility in common solvents, can be molded or cast into films or drawn into fibers, and are photoactive.
    Additional Material: 6 Ill.
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