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  • 1
    Electronic Resource
    Electronic Resource
    Adiabatic compressibility of solutions of ethylene-propylene copolymers in hydrocarbon solvents (1977)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 15 (1977), S. 279-282 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Adiabatic compressibility measurements are reported on solutions in hydrocarbon solvents of a low Mw high ethylene content, and of both high and low Mw low ethylene content ethylene-propylene copolymers. In all solutions the observed adiabatic compressibility was lower than the solvent value by an increment which was a function of the solvent type. Comparison of the data for a high and low molecular weight sample of the same copolymer indicates no molecular weight effects. Changes in the composition of the copolymer, as indicated by NMR spectroscopy, have only a slight effect on the adiabatic compressibility. The dominant feature of these studies is the apparent correlation of the chain length of the alkane solvent with the decrement in the compressibility.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1977.180150208
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  • 2
    Electronic Resource
    Electronic Resource
    Acoustic absorption and dynamic compressibility studies of dilute and concentrated solutions of polystyrene in toluene and cyclohexane (1977)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 15 (1977), S. 263-277 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Acoustic absorption and adiabatic compressibility measurements are reported on solutions of polystyrene (Mn = 89,000) in toluene and cyclohexane. The data in toluene cover a temperature range from 293 to 343°K and a concentration range of 10-400 Kg m-3 (1-40 wt%). The dependence of acoustic absorption on concentration was found to be linear up to 100 kg m-3, which corresponds to the concentration at which polymer-polymer interactions cause significant changes in the specific viscosity-concentration relationship. Up to 200 kg m-3 the data could be fitted to computations based on an artificial separation of the dispersion into contributions from viscoelastic and segmental processes, using parameters obtained from a study of narrow molecular weight distribution samples at 25 kg m-3. However, neither approach was capable of describing dispersions in the 300, 400 kg m-3 solutions. The modification of the relaxation spectrum observed at the highest concentrations is ascribed to volume and entropy changes associated with alterations of the local environment around a segment of the polymer chain. These changes have their origin in interchain penetration and polymer-polymer contacts, and indicate that ‘entanglement’ is primarily entropic in effect.The adiabatic compressibility exhibited similar deviations from a simple concentration dependence, and allowed estimation of an incompressible volume increment associated with polymer-polymer interactions in the high-concentration entangled matrix. However, the adiabatic compressibilities of solutions of polystyrene, 10-15 kg m-3, in cyclohexane showed no deviations from simple behavior in the region of the theta temperature. Measurements of the adiabatic compressibility of polystyrene in mixtures of cyclohexane-toluene have been used to obtain the relative magnitude of solvent and polymer contributions to the excess compressibility.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1977.180150207
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  • 3
    Electronic Resource
    Electronic Resource
    Ionic transport in a sulfonated polystyrene-polyethylene copolymer (1976)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 14 (1976), S. 1769-1787 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The conductivity of a grafted copolymer composed of 21% sulfonated polystyrene and 79% polyethylene has been investigated as a function of temperature and absorbed moisture for membranes containing the monovalent counterions H+, Li+, Na+, K+, Rb+, Cs, and Ag+. The mobility of Ag+ was measured directly in an experiment analogous to that used for the mobility of F-centers in alkali halides. The mobility and density of free counterions depend on the amount of absorbed water, but only the mobility and not the density of free counterions is a thermally activated process. Current is carried by both intrinsic counterions and, in samples containing absorbed water with greater than 1.5 V applied, by protonic carriers created when the absorbed water is electrolyzed. Thermal depolarization studies indicate that persistent polarization observed is the result of homogeneous volume polarization, due to the orientation of sulfonic acid side groups.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1976.180141004
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  • 4
    Electronic Resource
    Electronic Resource
    Chain mobility of some terephthalic acid polyesters in solution. A 13C spin-relaxation study (1979)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 17 (1979), S. 45-53 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Carbon-13 spin-lattice relaxation times (T1), nuclear Overhauser enhancements (NOE), and resonance linewidths (Δp) have been measured for a series of terephthalic acid polyesters containing ethyl, butyl, hexyl, and isopropyl groups between neighboring terephthalate units. The relaxation parameters of all carbons in the terephthalate groups are independent of the length of the separating alkyl chain. Reduced NOE's are seen for all carbons. The data are interpreted in terms of a log X2distribution of correlation times of constant width, but variable average mobility. The average mobility in the alkyl chain increases with increasing distance from the terephthalate group in a given polymer. For a given position in the chain. mobility increases with increasing chain length. This behavior is consistent with the presence of independently reorienting, highly solvated terephthalate groups.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1979.180170103
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  • 5
    Electronic Resource
    Electronic Resource
    13C-NMR sequence analysis of polyesters from pentaerythritol and caprolactone (1981)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 19 (1981), S. 1329-1336 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reaction of pentaerythritol (1) or dipentaerythritol with caprolactone yields prepolymers of the general structure \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm C} { \left( {\rm CH}_2 {\rm OH} \right)_4 } \hbox{--} {\rm i} \left [ {\rm CH}_2 {\rm O} \left( {\rm COCH}_2 {\rm CH}_2 {\rm CH}_2 {\rm CH}_2 {\rm CH}_2 {\rm O} \right)_{\rm n} {\rm H} \right]_{\rm i}$$\end{document} for i = 1, 2, 3, and 4 (2)-(5). The 13C chemical shifts of the quaternary carbons in (1)-(5) differ by more than 0.5 ppm. Conditions were determined to obtain quantitative intensity ratios of these carbons. The relative intensities give the distribution of the various branched structures and permit calculations of the average number of caprolactones per branch. Results are reported for caprolactone/polyol mole ratics of 3-66.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1981.170190605
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  • 6
    Electronic Resource
    Electronic Resource
    Chemiluminescence from polytetrafluoroethylene (1977)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 15 (1977), S. 99-106 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The chemiluminescence emission from commercial samples of polytetrafluoroethylene, PTFE (Halon G-80 and Halon G-10), was studied at temperatures between 25 and 172°C. The emission intensity decreased on extended heating, removal of the surface layer, solvent extraction, or changing from an atmosphere of oxygen to an inert atmosphere. Films of PTFE deposited from the vapor phase showed comparatively little chemiluminescence under these conditions. Ozone-induced chemiluminescence was observed at 37°C from G-10 but not from G-80, or from films deposited from the vapor phase. The chemiluminescence intensity from ozone and G-10 was not reduced by solvent extraction.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1977.170150110
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  • 7
    Electronic Resource
    Electronic Resource
    Low-molecular-weight polybenzimidazoles from aromatic dinitriles and aromatic diamines (1978)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 16 (1978), S. 2275-2284 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Three oligomeric benzimidazoles have been prepared by the oxidative cyclization of the corresponding polyamidines. These materials are high melting and are soluble in solvents like dimethylformamide. They exhibit inherent viscosities of 0.20-0.25 in DMF at 0.5g/100 ml. Several model compounds have also been prepared to show the feasibility and scope of the oxidative cyclization reaction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1978.170160916
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  • 8
    Electronic Resource
    Electronic Resource
    Sequence distribution in polyethylene/tetramethylene terephthalate copolyesters by 13C-NMR (1980)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 18 (1980), S. 559-563 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 13C-NMR gives sequence information in copolyesters synthesized from ethylene glycol (EG), 1,4-butane diol (BD), and methyl terephthalate (TP). The EG-TP-EG and BD-TP-BD blocks are distinguishable from the unsymmetrical diester sequence EG-TP-BD. The carbonyl and aromatic quaternary carbons of terephthalate have different chemical shifts but identical relaxation times and nuclear Overhauser enhancements in the three different triad sequences. Peak areas indicate random copolymerization of the three copolyesters studied.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1980.170180216
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  • 9
    Electronic Resource
    Electronic Resource
    N-methyl-substituted aromatic polyamidesPaper presented in part at the 28th Southeastern Regional Meeting of the American Chemical Society, Gatlinburg, Tennessee, October 1976. (1980)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 18 (1980), S. 1047-1059 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of N-methyl-substituted aromatic polyamides derived from the secondary aromatic diamines 4,4′-bis(methylamino)diphenylmethane, 3,3′-bis(methylamino)diphenylmethane, 4,4′-bis(methylamino)benzophenone or 3,3′-bis(methylamino)benzophenone and isophthaloyl dichloride, and terephthaloyl dichloride or 3,3′-diphenylmethane dicarboxylic acid dichloride was prepared by high-temperature solution polymerization in s-tetrachloroethane. Compared with analogous unsubstituted and partly N-methylated aromatic polyamides, the full N-methylated polyamides exhibited significantly lower glass transition temperatures (Tg), reduced crystallinity, improved thermal stability, and good solubility in chlorinated solvents.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1980.170180323
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  • 10
    Electronic Resource
    Electronic Resource
    Line broadening in the 13C NMR spectra of bulk polymers above Tg (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 2551-2559 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The effects of magic-angle sample spinning (MAS), high-power decoupling, and resonance frequency on the 13C NMR linewidths of bulk polyisobutylene and bulk trans-polybutadiene are examined. The 13C linewidths increase with resonance frequency, are unaffected by high-power decoupling, and are reduced to different extents by MAS. The dominant contribution of the natural linewidth of the polyisobutylene lines is confirmed. The two carbons of trans-polybutadiene have approximately equal linewidths under all conditions, a result that eliminates residual chemical shift anisotropy as a major contributor to the linewidths. The large reduction of the trans-polybutadiene linewidths with MAS, coupled with the above result, suggests that microscopic variation of magnetic susceptibility is the major factor for this semicrystalline polymer. Cross-polarized 13C spectra of trans-polybutadiene were obtained with and without MAS. With MAS, resonances due to the crystalline and amorphous components were resolved. The principal components of the chemical shift tensor of the vinylene carbons were obtained from the spectrum without MAS.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180211211
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