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  • Physics  (517)
  • 1980-1984  (517)
  • 1925-1929
  • 1982  (517)
  • 1
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 241-244 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A simplified approximation method for the treatment of dead-end and high conversion polymerization kinetics is presented. The method is based on the treatment of dead-end polymerization first described by Tobolsky. In appropriate circumstances, by contrast with Tobolsky's method, this method provides measurements of kd and kp/kt1/2 without recourse to the measurement of the monomer conversion at infinite time.Kinetic studies of free radical polymerizations are normally confined to measurements of initial rates. At low conversions the predictions of the general mechanism for chain-growth polymerization involving initiation, propagation, and termination steps are generally obeyed. Thus the polymerization rate should be first order in the vinyl monomer and half-order in the initiator concentrations.At high conversions, however, large deviations which can be ascribed to various effects can occur; for example, (1) the effect of the increasing viscosity of the polymerization medium on the termination rate constant kt, and possibly also on the propagation rate constant kp, which have been considered by North1 and Cardenas and O'Driscoll,2 or (2) depletion of the initiator as the polymerization progresses. This depletion will occur in all polymerizations but its significance will depend on the magnitude of the rate constant for initiator decomposition (kd) and the period of polymerization. Appropriate conditions will lead to limiting monomer conversion even after infinite polymerization time; this phenomenon has been called dead-end polymerization by Tobolsky.3Free radical polymerizations to high conversion are particularly important in the industrial context when initial kinetics are obviously inadequate. Suitable treatment of the conversion/time relationship is highly desirable.Senogles and Woolf4 have examined the polymerization of n-lauryl methacrylate at 60°C with 2-azobisisobutyronitrile as initiator under dead-end conditions.Here we propose a modification of Tobolsky's treatment of such polymerizations by using an approximation for the exponential decay in the initiator concentration. This method permits easy manipulation of the experimental data and the estimation of values for the kinetic parameters in favorable circumstances without recourse to the measurement of the conversion at infinite time or the evaluation of complicated functions of the monomer conversion. The method thus allows the duration of the laboratory experimentation to be significantly shortened and the complexity of the subsequent data analysis to be considerably reduced.
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  • 2
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 257-261 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 3
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 263-265 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 4
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 269-275 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A novel class of poly(metal phthalocyanino) benzimidazoles were prepared by the condensation reaction between metal (Cu, Co, and Zn), 4,4′,4″,4‴-tetracarboxyphthalocyanine, and 3,3′-diaminobenzidine. The reaction was investigated by melt and solution condensation methods. These polymers showed excellent thermal and thermooxidative stability and are noteworthy for their high char yield (86-90%) at 800°C in an anerobic atmosphere. Elemental analyses, spectra, and TGA studies were used to characterize these materials. Isothermal gravimetric analyses were carried out to determine their long-term thermal stability.
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  • 5
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 277-282 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ethyl acrylate (EA) and n-butyl methacrylate (n-BMA) copolymers were prepared in solution and the composition of the copolymer samples was estimated by 1H-NMR spectroscopic techniques. Because the characteristic signals, which vary with the composition of the copolymer, were absent, the ratio of intensities of down-field protons to that of the total protons was used for the estimation of copolymer composition. Reactivity ratios were calculated from these values by using the Kelen-Tudos differential linear equation.
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  • 6
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 299-310 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Amphiphilic block copolymers consisting of methacrylic acid (MA) sequences and p-N,N-dimethylaminostyrene (DMS) sequences were prepared by living anionic polymerization. DMS was polymerized by lithium naphthalene in tetrahydrofuran to yield a living polymer solution, to which trimethylsilyl methacrylate (TMSM) was added to allow the block copolymerization. The conversion of TMSM was dependent on the countercation, i.e., with Na+ as counterion, no quantitative conversion was reached owing to premature termination, whereas with Li+ the conversion was quantitative. The role of the counterion was discussed in some detail in connection with self-termination by the backbiting mechanism. The trimethylsilyl ester groups in the block copolymer were quantitatively hydrolyzed by treatment with aqueous methanol at room temperature, yielding MA sequences. The block copolymer of MA and DMS exhibited micellar properties in an aqueous solution.
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  • 7
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ten structurally different bisimide resins were prepared by reacting maleic anhydride/citraconic anhydride and benzophenone tetracarboxylic dianhydride with aromatic diamines and fused aromatic structures or heterocyclic groups. The amines included were 1,5-diaminonaphthalene, 2,5-bis(p-aminophenyl)1,3,4-oxadiazole, 3,3-bis(p-aminophenyl)phthalide, 9,9-bis(p-aminophenyl)fluorene. and 10,10-bis(p-aminophenyl)anthrone. These monomers were characterized by infrared (IR). 1H-NMR, mass spectroscopy, and elemental analysis. Thermal polymerization of these monomers was investigated by differential scanning calorimetry. Broad exothermic peaks were observed for a temperature range of 225-380°C. Temperature of exothermic peak position was influenced by the presence of substituents at the olefinic bond, and in biscitraconimides it was 40-50°C lower than in the corresponding bismaleimides. Anaerobic char yields of cured bisimide resins ranged from 44 to 64%. Oxadiazole-containing bisimides had low thermal stability. Increase in formula weight between the imide groups did not influence the char yields in a systematic manner. Graphite cloth laminates with two of these bisimide resins were fabricated and tested for a number of physical properties. Their limiting oxygen index was 70-72%.
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  • 8
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2765-2772 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Charge transfer (CT) interaction is described in semiconducting dispersions of TCNQ complex salt \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm Et}_3 {\rm NH}^+ ({\rm TCNQ})_2^{\cdot^{\hskip-3.7pt\hbox{--}}}$\end{document} with and without added TCNQ°, in poly(vinyl acetal) matrices in which the electron-donor moiety is varied. The extent of CT interaction was determined in films and in solution (DMF, acetonitrile, or methylene chloride) through the absorbances at 398 nm (\documentclass{article}\pagestyle{empty}\begin{document}$ {\rm TCNQ}{\ }^{\cdot^{\hskip-3.7pt\hbox{--}}}$\end{document} and TCNQ°) and 857 nm \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm TCNQ}{\ }^{\cdot^{\hskip-3.7pt\hbox{--}}}$\end{document}. Resistivity of the conductive films was related to the stoichiometry of TCNQ species in the films and found to have a minimum at \documentclass{article}\pagestyle{empty}\begin{document}$[{\rm TCNQ}^\circ]/[{\rm TCNQ}{\ }^{\cdot^{\hskip-3.7pt\hbox{--}}}]\simeq 1$\end{document}. Lower resistivities were attained with films having a uniform, densely packed dispersion of microcrystallites which were obtained at a relatively slow solvent removal rate. With this particular complex salt, strong electron-donor polymers are found to be better matrices for semiconductivity.
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  • 9
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2773-2780 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(metal phthalocyanine)imides of copper, cobalt, nickel, and zinc were synthesized by the reaction of metal phthalocyanino tetramines with benzophenone tetracarboxylic dianhydride. These polymers were characterized by elemental analyses and IR, TGA, and inherent viscosity studies. Noteworthy features of these phthalocyanine polymers are their remarkable thermal and thermooxidative stabilities with char yields at 800°C that range from 78 to 83% in a nitrogen atmosphere. The relative thermal stabilities of these polymers have been evaluated by activation energy measurements.
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  • 10
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2781-2789 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New poly(metal phthalocyanine) pyromellitimides of copper, cobalt, nickel, and zinc were synthesized and elemental, IR, TGA, and inherent viscosity measurement studies were done to characterize these polymers. They showed exceptional thermal and thermo-oxidative stability with char yields at 800°C ranging from 75 to 87% in a nitrogen atmosphere. The ratio of the polymer decomposition temperatures in air and nitrogen (PDT) (air)/PDT (N2) varied from 0.91 to 0.97, which indicated that the onset of degradation of these polymers is greatly affected by the presence of an oxidizing atmosphere. Isothermal studies were done to evaluate the long-term thermal stability of these polymers.
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  • 11
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Alternating copolyamides of various ω-amino acids were synthesized by base-catalyzed polycondensation of N-isothiocyanatoacyl ω-amino acids in solution. Derivatives of the following amino acids were used: glycine, β-alanine, γ-aminobutyric acid, δ-aminovaleric acid, ε-aminocaproic acid, D,L-β-aminobutyric acid, trans-4-aminocyclohexane 1-carboxylic acid, 4-aminophenyl acetic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, 3-amino-4-methyl benzoic acid, and 4-amino-3-methyl benzoic acid. The base-catalyzed polycondensation at lower temperatures gave purer products than the bulk condensation at 180-200°C. 13C-NMR and natural-abundance 15N-NMR spectra measured in trifluoroacetic acid demonstrate that in most cases undisturbed alternating sequences were obtained. Strong neighboring residue effects and long-range sequence effects were found in the 15N-NMR spectra, and structure/shift relationships are discussed. The sequences of copolyamides obtained by copolymerizations of lactams or β-amino acid N-carboxyanhydrides were investigated by both 15N-NMR and 13C-NMR spectroscopy. 13C-NMR spectroscopy was found to be more useful if the copolyamides consist of ω-amino acid units of different chain length. However, 15N-NMR spectroscopy is more suited if the monomer units differ exclusively by their substituents.
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  • 12
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2809-2817 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This article concerns the synthesis and characterization of new epoxy and aldehyde telechelic polyisobutylenes, that is, and . The synthesis of the epoxy derivative was achieved by quantitative epoxidation of α,ω-di(isobutenyl) polyisobutylene with m-chloroperoxybenzoic acid and that of the dialdehyde by quantitative isomerization of the epoxy termini with zinc bromide. Infrared (IR) and 1H-NMR analysis of these new telechelic polymers and ultraviolet (UV) analysis of the 2,4-dinitrophenylhydrazine derivative of the dialdehyde indicate quantitative conversions and yields, that is, essentially theoretical functionalization (Fn = 1.95 ± 0.05).
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  • 13
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2819-2828 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of α-methylene-γ-butyrolactone (α-MBL) homopolymerization was investigated in N,N-dimethylformamide (DMF) with azobis(isobutyronitrile) as initiator. The rate of polymerization (Rp) was expresed by Rp = k[AIBN]0.54[α-MBL]1.1 and the overall activation energy was calculated as 76.1 kJ/mol. Kinetic constants for α-MBL polymerization were obtained as follows: kp/kt1/2 = 0.161 L1/2 mol-1/2·s-1/2; 2fkd = 2.18 × 10-5 s-1. The relative reactivity ratios of α-MBL(M2) copolymerization with styrene (r1 = 0.14, r2 = 0.87) were obtained. Applying the Q-e scheme led to Q = 2.2 and e = 0.65. These Q and e values for α-MBL are higher than those for MMA
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  • 14
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2829-2838 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of methacryloyl fluoride (MAF) homopolymerization was investigated in methyl ethyl ketone (MEK) with azobis(isobutyronitrile) as initiator. The rate of polymerization (Rp) followed the expression Rp = k[AIBN]0.55[MAF]1.18. The overall activation energy was calculated as 74.4 kJ/mol. The relative reactivity ratios of MAF(M2) copolymerization with styrene (r1 = 0.083, r2 = 0.14), and methyl methacrylate (r1 = 0.48, r2 = 0.81) in methyl ethyl ketone were obtained. Application of the Q-e scheme (in styrene copolymerization) led to Q = 2.22 and e = 1.31. The glass transition temperature (Tg) of poly(MAF) was 90°C by thermomechanical analysis. Thermogravimetry of poly(MAF) showed a 10% weight loss of 228°C in air.
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  • 15
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2851-2862 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of acetylene-terminated quinoxaline oligomers was synthesized for testing as possible adhesives for airplane manufacturing.
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  • 16
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 529-539 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Copolymerization of N-carboxy N∊-carbobenzoxy L-lysine anydride with N-carboxy β-benzyl L-aspartate anhydride was initiated with n-butylamine in acetonitrile. The copolymerization proceeded almost homogeneously except for the initial stage, when the proportion of N-carboxy anhydride (NCA) in the polymerization mixture varied from 25 to 75 mol %. This was due to the fact that the copolypeptides formed were soluble or highly swollen in the solvent, in contrast to the homopolymerization of NCAs such as N∊-carbobenzoxy L-lysine NCA and β-benzyl L-aspartate NCA in acetonitrile, which proceeds heterogeneously. The compositions of the copolymers obtained were, within experimental error, the same as their monomer feed compositions. The initial rates of copolymerization were almost the same as the rate of homopolymerization of β-benzyl L-aspartate NCA, which propagates with a nonhelical polypeptide, but were slower than the rate of homopolymerization of N∊-carbobenzoxy L-lysine NCA, which propagates with a helical polypeptide.
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  • 17
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 555-563 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Effect of polyanions on the aggregation of methylene blue (MB) was investigated spectrophotometrically. The following polyanions were used: potassium poly(vinyl sulfate), potassium poly(styrenesulfonate), sodium poly(methacrylate), and sodium poly(acrylate). The state of aggregation was largely dependent on the kind of polyanion and polyanion-MB ratio. MB-photo-sensitized isomerization of cis-p-(phenylazo)phenyltrimethylammonium iodide(cis-PTA) to the transisomer was used advantageously to investigate the effect of dye aggregation on the triplet excitation energy transfer between cationic dyes bound to polyanions. Although the efficiency of the excitation energy transfer between MB and cis-PTA was enhanced by the addition of polyanions, the formation of highly aggregated MB reduced the efficiency of the excitation energy transfer. Correlation with the dye aggregation induced by polyanions and the efficiency of excitation energy transfer between dyes was discussed.
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  • 18
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 663-673 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polybenzimidazoles that contained anthracene photodimer were prepared. The molecular weights of the polymers prepared by the photopolymerization of bis-anthrylbenzimidazoles were limited by the precipitation of the resulting polymers from the reaction organic solvents. Higher molecular weight polymers were obtained by the photopolymerization of bis-anthryl-Schiff's bases, followed by the oxidation of the resulting polymers. These polymers were soluble in acidic solvents such as formic and sulfuric acids but were insoluble in organic solvents.
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  • 19
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 675-681 
    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 the presence of a mixed ligand complex, [N,N′-ethylenebis(salicylideneiminato)](acetylacetonato)cobalt(III) in benzene was studied. The rate of polymerization was proportional to the square root of the concentration of the chelate and the monomer exponent was 1.67 and 1.69 at 60 and 70°C, respectively. The activation energy and the kinetic and transfer constants were evaluated. A free-radical mechanism has been proposed.
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  • 20
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 707-724 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetic behavior of a Cr6+/Cu2+ system in its reaction with wood has been elucidated. The same reactions with carbohydrates and lignin of wood for CrVI alone are still present. Approximately 20% of the copper is fixed to the guaiacyl units of lignin in the form of copper chromate; the remaining copper forms complexes with cellulose and mainly with the guaiacyl units of lignin. The CrVI/lignin guaiacyl unit complexes already found for the treatment of wood with CrO3 are still the main CrVI complexes formed. Copper chromate is present as [Cu(H2O)2(guaiacol)]CrO4(guaiacol) complexes, and CuCrO4 bridges between different guaiacyl units of the lignin network appear to be likely. Substantial interference of the Cu2+ ions in the second-zone reactions of CrVI with wood occurs. The amount of CrVI and CrIII fixed onto lignin and cellulose compares well with experimental values. Rate constants, energies of activation, and Arrhenius equations of the various reactions have been obtained. The amount of Cu2+ interference in the reaction has also been calculated.
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  • 21
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 683-689 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Random polyamide-esters were prepared directly by the interfacial and solution polycondensation of 4-(4-amino-α,α-dimethylbenzyl)phenol (I) with iso- and terephthaloyl chlorides. Authentic samples of ordered polyamide-esters with an amide-amide-ester-ester structure were synthesized by the two-step procedure; that is, the preparation of amide-bisphenol monomers from I and subsequent polycondensation with aromatic diacyl chlorides. The random and ordered polyamide-esters differed from one another with respect to solubility in organic solvents and glass transition temperature, whereas all the random and ordered polymers were of equal low crystallinity. All of these polymers began to decompose around 350°C in both air and nitrogen atmospheres.
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  • 22
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 691-706 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Perfluoro-2-butyl tetrahydrofuran was polymerized by an RF glow discharge technique and detailed ESCA studies were made of the resultant films. The rate of film deposition was sensitively dependent on the W/FM parameter and the site of deposition. The ESCA data show that the molecular rearrangement accompanying plasma polymerization and the oxygen functionality is at a significantly lower level than the starting material. Under appropriate conditions plasma polymerization produces material with a C:F stoichiometry of 1:2, although the ESCA data show that the polymer is drastically different from PTFE. ESCA studies are also reported on thin films of the monomer studied at low temperature.
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  • 23
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 725-738 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetic behavior of a Cr/As system in its reaction with wood is described, as are its reactions with lignin and carbohydrates of wood for CrVI alone. ChromiumIII arsenate complexes with the guaiacyl units of lignin, as well as the usual chromic acid/guaiacyl unit complexes already characterized, was formed. The interference of As concentration on the various zones of fixation of chromium are identified. Complexes between guaiacol and chromium arsenates indicate that in this Cr/As system CrIII can also be linked to the guaiacyl units of lignin when in the form of CrAsO4·6H2O contrary to what obtained with systems not containing As. An initial increase in the rate of reduction CrVI → CrIII by the carbohydrates fraction in wood is ascribed to the catalytic effect of the arsenic. The percentages of chromium fixed onto lignin and cellulose of wood compare well with experimental values.
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  • 24
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 765-774 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Complex dielectric constants were measured at frequencies of 0.1-10,000 kc/s over the temperature range of 0-60°C in medicated cotton cellulose and viscose. In these fibers evidence is found for a new secondary relaxation process within the frequency region of 0.1-1 kc/s. The significance of the results is discussed.
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  • 25
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3107-3114 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyethylene films were evaporated in gas plasmas of Ar, N2, O2, and H2O. The deposits were analyzed by infrared (IR) spectroscopy to determine the concentration of characteristic functional groups. The deposit prepared in Ar-atmosphere had a rather high concentration of methyl group and many double bonds were produced in the film. The deposits prepared in Ar- and N2-plasmas produced similar spectra, which showed twice the concentration of methyl group than the deposit in Ar-atmosphere and also contained a few carbonyl and hydroxyl groups. The film treated in O2-plasma contained the largest amount of carbonyl group and the lowest number of double bonds among the plasma-treated deposits. Dielectric loss curves against temperature for the deposits treated in these plasmas showed a broad peak near 20°C. For O2-plasma-treated film the loss tangent curves showed a sharp maximum. The activation energy for the relaxation of Ar-, O2-, and H2O-plasma-treated films had the same value of 50.6 kcal/mol. The observed relaxation in the films prepared in gas plasmas was considered due to the β process and was attributed to the motion of oxidized branched polyethylene.
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  • 26
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 775-782 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Spin-lattice relaxation times and nuclear Overhauser enhancements (NOE) for 13C nuclei in copolymers of acrylonitrile and vinylidene chloride were measured at 20.1 and 67.9 MHz. In the —CCl2— region of the spectrum T1 and NOE values of the various resonances are equal within experimental error and are invariant to changes in composition. The T1 and NOE values of the —CCl2— region, however, are not equal to those of the —CH— or —CN region. As a result compositions cannot be calculated by direct comparison of the areas in the —CCl2— region and either the —CH— or the —CN region. Discrepancies can be corrected for the —CH— resonances by multiplication of the area by an empirical constant. A similar constant for the —CN region is composition-dependent at 20.1 and 67.9 MHz. A chemical shift anisotropy mechanism is postulated as important for relaxation of the —CN resonances. The overall influence of variable T1 and NOE values on quantitative determination of polymer composition is considered.
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  • 27
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 783-793 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: It was found that 1-substituted quaternary imidazolium compounds show some characteristic infrared (IR) activity. On quarternization of 1-substituted imidazoles strong absorption bands appeared at about 1150 and 1550 cm-1 in the IR spectra of these compounds. The band at 1150 cm-1 was assigned to the position 2 C-H bending mode and the 1550 cm-1 band was attributed to a ring vibration mode of the quaternary imidazolium compounds. The concentration of the quaternary imidazolium units in a polymer can be determined by measuring the intensity of the absorption bands at 1150 or 1550 cm-1 in relation to another suitable absorption band of the spectrum.
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  • 28
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3147-3154 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The star-branched polymers on the tetrahedral lattice are studied by means of the Monte Carlo method. The influence of solvent quality on the dimensions of the coil is described for both linear and branched polymer systems of different functionality. It has been observed that the ratios of gyration radii 〈S2〉b/〈S2〉l are greater than those predicted theoretically for the random-flight model. The fourth reduced moment of S2 distribution and the mean-square separation of the branch ends from the center of gravity have been also computed. The changes in segment arrangement in the coil with increasing number of branches have been observed.
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  • 29
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 795-810 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Isothermal emulsion polymerization at 60°C of styrene in a batch reactor were studied by using sodium lauryl sulfate as surfactant and potassium persulfate as initiator source. The concentrations of surfactant and initiator were varied during the runs. The polymerization evolution was followed as samples were taken at regular intervals. These emulsion samples were analyzed for monomer conversion, rate of polymerization, as well as for the size and the size distribution of the particles. The molecular weight and molecular weight distribution were obtained by gel permeation chromatography. Our study showed that fresh nucleation takes place even at high conversion, causing a continuous shifting toward broadening of particle size distribution. Contrary to the theory of Smith and Ewart, which assumes a constant number of particles during interval II of the polymerization reaction, our digital simulation of the reaction presents better experimental results with a variable number of particles, and indicates that the Hui-Hamielec model for termination constant kt as function of conversion is not applicable under our working conditions.
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  • 30
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 817-838 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Random copolymers of acrylamide with sodium-2-sulfoethyl methacrylate and with sodium-2-acrylamido-2-methylpropane sulfonate were synthesized in aqueous solutions utilizing persulfate initiators. Copolymer compositions were determined by elemental analysis and by infrared spectroscopic methods. Monomer reactivity ratios were calculated using Fineman-Ross, Kelen-Tüdos, and/or Mayo-Lewis techniques at appropriate conversions. The copolymer microstructure, including mean sequence length distributions, was calculated from reactivity ratios. Membrane osmometry and viscometry measurements were utilized to estimate molecular weight and size. The large dimensions of these polyelectrolytes in aqueous solutions, as well as their inherent hydrogen bonding capacity and pseudoplasticity, make these copolymers excellent candidates for application as mobility control agents in enhanced oil recovery.
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  • 31
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 839-846 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyiodide formed by complexation of poly(vinyl acetate) (PVAc) with iodine in the presence of iodide has been investigated by chemical analysis and resonance Raman spectrophotometry. When PVAc films were immersed in iodide-iodine aqueous solutions which had different ratios of iodide to iodine concentration [I-]/[I2], the complex films exhibited tremendous variations of swelling degree, despite the relatively small change in the amount of bound iodine. From a quantitative chemical analysis, the composition of polyiodide bound to PVAc was found to be 1.01 ± 0.035 in the molar ratio of iodide to iodine irrespective of the composition of the iodide-iodine aqueous solution ([I-]/[I2] = 2-500). The polyiodide formed in PVAc-iodine-iodide complex was therefore inferred to be (I3-)n. Resonance Raman spectra obtained on PVAc-iodine-iodide complexes were also identical to those of the benzamide-iodine complex, in which the polyiodide consists of (I3-)n, consistent with the result from chemical analysis.
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  • 32
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3189-3197 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of poly(vinyl chloride) powder with aqueous sodium hydroxide solution in the presence of quaternary ammonium or phosphonium halides yielded dehydrochlorinated products of conjugated polyene structure. The reaction was discussed in terms of a phase transfer catalytic mechanism between aqueous and polymer phases. Among the catalysts used tetrabutylammonium bromide was the best. To obtain the optimum conditions the effects of reaction temperature, the concentration of NaOH and the catalyst, and the molecular weight of poly(vinyl chloride) were investigated. Treatment of PVC films and solutions in tetrahydrofuran with aqueous NaOH solutions under two-phase conditions also produced dehydrochlorinated films and powders.
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  • 33
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3199-3205 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Lithium-metallated (styrene-p-benzylstyrene)copolymer was reacted with chlorine-terminated polystyrene as a crosslinker polymer in a mixture of tetrahydrofuran (THF)-n-hexane at 25°C in the presence of lithium chloride(LiCl). The rate constants were estimated from the changes in the concentration of metallated polymer by photometrical measurements. As a result, the rate constant of grafting (k1) showed a constant value in spite of a change in molecular weight of the crosslinker polymers and the addition of n-hexane. The rate constant of intramolecular crosslinkings (k2intra) obtained in a mixed solvent (21 ∼ 36 vol % of n-hexane) increased when the molecular weight of the crosslinker polymers and the extent of n-hexane were increased.
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  • 34
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3207-3217 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Radical cyclopolymerization of allyl methacrylate (AMA) was investigated in detail, especially under the specified conditions; that is, above the ceiling temperature for a head-to-tail propagation (ΔGht ≥ 0) in the polymerization of methacrylate. Thus the structure of the polymer obtained was examined by 1H- and 13C-NMR and infrared (IR) spectroscopy; no existence of unreacted pendant methacrylyl groups was observed, which suggests that, as a cyclopolymerization mechanism of AMA, intermolecular propagation of growing radicals, followed by intramolecular cyclization or intermolecular propagation of the resulting uncyclized methacrylyl radical, occurs exclusively with methacrylyl group. Temperature dependency of cyclization constant Kc was unusual; Kc increased rapidly at elevated temperatures and no linear relationship of ln Kc vs. 1/T was observed. Five-membered ring formation was favored at an elevated temperature and diluted monomer concentration. These results are discussed thermodynamically in terms of controlled ring closure in cyclopolymerization.
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  • 35
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    Topics: Chemistry and Pharmacology
    Notes: β-Pinene was polymerized with H2O/BCl3 (protic) and p-dicumyl chloride and sym-tricumyl chloride (nonprotic) inifer systems in CH2Cl2 or CH2Cl2/n-C6H14 solvents from -10 to -70°C. The effect of solvent polarity, temperature, and monomer and inifer concentration on conversions and molecular weights was investigated. Low conversions and molecular weights, M̄n = 1300-2500, obtained under these conditions suggest rapid termination.
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  • 36
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 901-915 
    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 1.3-cyclohexadiene (1.3-CHD) was investigated in temperatures that ranged from 25 to -77°C. Initiation by lithium naphthalene (N-·,Li+) in tetrahydrofuran at -20°C yields polymers with fairly narrow molecular weight distribution. The M̄w of these polymers so prepared is ca. 20,000. Polymerization of 1.3-CHD conducted at room temperature is accompanied by the dehydrogenation and disproportionation of the monomer, especially when N-·,K+ acts as initiator. Oligomers are formed when hexamethylphosphoramide is used as a solvent. The mechanism of the initiation of the polymerization of 1.3-CHD by N-·,Li+ was elucidated and the rate constants at -20°C in tetrahydrofuran of the elementary reactions were determined. It was established that the dianions formed by disproportionation of N-·,Li+ act as effective initiators for 1.3-CHD. The adducts formed constitute the cyclohexanyl and naphthyl carbanionic groups. The former carbanions (λmax ∼ 275 nm) propagate the polymerization. The initially formed dimeric adducts are stabilized by the separation of the carbanionic end groups by the additional monomer units. Chain transfer to the monomer limits the growth of the polymers. The isomerization of the cyclohexadienyl anions, formed as result of chain transfer, may be followed by the elimination of lithium hydride. The latter reaction represents a termination step. Addition of 1.4-CHD to the reaction mixture enhances the chain transfer and the termination.
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  • 37
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 929-938 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Studies of the effect of aqueous Br2 solution on the fine structure of cellulose have shown that the accessibility of the cellulose is a complex function of the duration of treatment. Following immersion of rayon-cellulose in the Br2 solution, its accessibility is observed to increase until a peak is reached, after which the accessibility decreases with time. For higher temperatures and greater concentrations of Br2, a sharper peak and faster rates of increase and decrease of accessibility are obtained. In order to explain this behavior, a mathematical model of the kinetics is postulated involving two opposing first-order processes occurring simultaneously. One process describes the decrystallization of crystalline regions within the cellulose by opening intermediate linkages due to Van-der-Waals forces involved. The second process relates to the crystallization of the less-ordered regions. The rate constants for these processes are determined by fitting experimental curves to the postulated analytical expression with the aid of a digital computer program. Experiments carried out on high-modulus rayon showed that for this type of cellulose, the effect described above was very pronounced. From the calculated rate constants, the activation energies of the crystallization and decrystallization reactions were determined. The plots of the rate constants versus 1/T showed that a break occurs at 25°C, corresponding to a second-order transition point of cellulose. The energies of activation of the crystallization process are in the range of 7-9 and 10-13 kcal/mol in the temperature ranges 10-25 and 25-40°C, respectively. The activation energies of the decrystallization process are 13 and 18-24 kcal/mol in these temperature ranges.
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  • 38
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3265-3265 
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    Keywords: Physics ; Polymer and Materials Science
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    Topics: Chemistry and Pharmacology
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  • 39
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3267-3270 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the basic hydrolysis of several poly(phenyl methacrylates) with different substituents in the aromatic ring were investigated. Using Keller's equations to describe the effect of neighboring groups on the kinetics of side-group reactions in polymers, we computed the corresponding rate constants which correlated well with Hammett's substituent constants.
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  • 40
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3271-3283 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A commercially available densimeter with a vibrating stainless steel tube was used as a detector in the GPC analysis of styrene/methyl methacrylate copolymers under normal GPC operational conditions. The densimeter was thermostated to ±0.001°C and sample injection concentrations were 4.0 mg/mL. The copolymer samples were polydisperse in molecular weight but uniform in composition. A refractive index detector and the densimeter detector produced comparable estimates of the parameters of the molecular weight distributions. The densimeter is less sensitive to the effects of variations in copolymer composition than differential refractive index or ultraviolet detectors. The only serious drawback to the densimeter is a relative lack of sensitivity. Variations in composition of styrene/methyl methacrylate copolymers over a fairly wide range have no signficant effect on the relation between gel permeation chromatographic elution volume and copolymer molecular weight. In general, however, conventional means of summarizing these data are not applicable to compositionally heterogeneous mixtures. Instrumental and data-handling solutions to this problem are discussed.
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  • 41
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3285-3296 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 13C-NMR spectra of bulk acrylonitrile-butadiene-styrene (ABS) resin are reported. The styrene-co-acrylonitrile (SAN) carbons can be observed selectively by using high-power proton decoupling, cross polarization, and magic angle spinning (MAS). The polybutadiene (PBd) carbons can be observed selectively by using low-power proton decoupling, with or without MAS. Methods and conditions for using 13C-NMR to quantify the amount of PBd in solid ABS resins are developed. The 13C-NMR results and results from iodine monochloride titrations for PBd content are in good agreement. Resonances of PBd in ABS in the solid state are assigned on the basis of triad sequences of cis, trans, and vinyl-1,2 geometric isomers of butadiene. Computational methods are set forth for measuring directly from the 13C-NMR spectra the percent of cis, trans, and vinyl-1,2 isomers in PBd in the ABS resin. The NMR measurement of PBd microstructure appears to be preferable to infrared (IR) determinations. Relaxation parameters (T1 and NOE) are reported for PBd in bulk ABS as a function of temperature and are analyzed in terms of a distribution of rotational correlation times. These relaxation parameters are similar to those of nongrafted PBd and indicate that the local motions in grafted and nongrafted PBd are similar.
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  • 42
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3305-3312 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The second moments of the ESR signals obtained from poly(p-phenylene) (PPP) and deuterated PPP were measured at 9.5 and 35 GHz. The theoretical and experimental contributions to the second moments were considered. It is shown that for deuterated PPP, deuteron hyperfine splitting makes a negligible contribution to the observed second moment. The proton hyperfine contributions to the second moments of the radical species in PPP and p-sexiphenyl were estimated and it was concluded that the unpaired electron was delocalized over only 2-4 phenylene units. A rationale is offered in terms of polarons present as defects in the PPP chains.
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  • 43
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1011-1019 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The characteristics of the photoinduced electron transfer reaction from polystyrene pendant tris(2,2′-bipyridyl)ruthenium (II) complex [Ru(bpy)32+] to methylviologen (MV2+) were studied. The rate constant k1 from the excited state of the complex, Ru(bpy)32+*, to MV2+ were determined for both the polymeric and monomeric complexes from the lifetime τ of Ru(bpy)32+* and the quenching rate of Ru(bpy)32+* by MV2+. The polymer pendant Ru(bpy)32+* showed three kinds of τ components ranging from 7 to 474 ns, in contrast to the monomeric complex, which showed one component of 350 ns. The k1 values for both complexes were almost the same, on the order of 108 L/mol s. The photoinduced electron transfer from solid-phase Ru(bpy)32+ to liquid-phase MV2+ was realized by utilizing the polymer complex, and the solid-liquid interphase reaction system is discussed.
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  • 44
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3337-3350 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: It was found that structurally isomeric polymers were formed by the ring-opening polymerization of β-(2-acetoxy ethyl)-β-propiolactone with (EtAlO)n and Et(ZnO)2ZnEt catalysts; that is, the Al catalyst catalyzed normal polymerization which led to poly-β-ester and the Zn catalyst formed isomerized poly-β-ester as the main product. The polymer structure was determined by nuclear magnetic resonance (NMR), T1-value, thermal decomposition product, and (Tg). The NMR studies for the monomer-catalyst systems indicated that the Al catalyst interacted predominately with the lactone group, whereas the Zn catalyst interacted with the side-chain ester group. These site-selective interactions could be related to the difference in the stereoregulation by the two catalysts during the poly(β-ester)-forming polymerization process.
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  • 45
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3351-3368 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polydimethylsiloxane oligomers with silanol ends condense in aqueous dispersion under mild conditions to form high polymers in the presence of sulfonic acid surfactants. The process follows a second-order rate law in silanol if reversibility is taken into account. The second-order rate constant is proportional to the area at the oil-water interface and is a complex function of surfactant concentration. The principal driving force is the heat of condensation of the water produced in the polymerization. A mechanism paralleling surface catalysis is offered in which a termolecular complex that consists of two surfactant molecules and one silanol end group reacts bimolecularly at the oil-water interface.
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  • 46
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3369-3376 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This article deals with the kinetics and mechanism of acrylonitrile (AN) polymerization initiated by Cu(II)-4-anilino 3-pentene 2-one[Cu(II)ANIPO], Cu(II)-4-p-toluedeno 3-pentene 2-one [Cu(II)TPO], and Cu(II)-4-p-nitroanilino 3-pentene 2-one [Cu(II)NAPO] in bulk at 60°C. The polymerization is free radical in nature. The exponent of initiator(I) is ≃ 0.5. The initiation step is a complex formation between the chelate and monomer and subsequent decomposition of the intermediate complex giving rise to free radical and Cu(I). This is substantiated by ultraviolet (UV) and electron spin resonance (ESR) studies. The activation energies and kinetic and chain transfer constants have also been evaluated.
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  • 47
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3377-3385 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cationic copolymerization of tetrahydrofuran-(A)-3,3-dimethyloxetane (B) was studied at 0°C with BF3·OEt2-epichlorhydrin and acetylhexafluoroantimonate as initiators. The values of the reactivity ratios, calculated by the Fineman-Ross and Kelen-Tüdos methods, were rA = 0.13, rB = 8.1 and rA = 0.13, rB = 7.9, respectively. These values are in satisfactory agreement with those obtained with a kinetic scheme in which depropagation reactions were considered. The product rArB was approximately equal to unity, which indicated an ideal random copolymerization. The copolymers were also analyzed by 1H-NMR spectroscopy. Their spectra presented a doublet at 3.1 and 3.15 ppm that corresponded to the methylene protons of the dimethyloxetane units and allowed the determination of the probabilities P(AA), P(AB), and P(BB). Good agreement was found between the values calculated by spectroscopic methods and those obtained by using the classical probability theory of copolymerization.
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  • 48
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3387-3397 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A novel class of polyamide-quinazolinediones was synthesized by the polymerization of 2,2′-disubstituted bis(1,3,4-oxadiazolin-5-ones) with aromatic bis-o-amino esters in m-cresol. The polymerization probably proceeded in the formation of ring-opening adducts, which in turn were cyclized by the elimination of alcohol to give polyamide-quinazolinediones. These polymers, which were soluble in polar aprotic solvents such as dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, and dimethyl sulfoxide, had, with one exception, reduced viscosities in the range of 0.12-0.32 dL/g. Thermogravimetric analyses indicated that they began to decompose at 310-360°C in air.
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  • 49
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3421-3429 
    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 1-halooctanes with aqueous sodium cyanide catalyzed by phosphonium salts attached to insoluble polystyrene resins by tetramethylene or heptamethylene spacers was studied as a function of catalyst particle size, degree of polymer crosslinking, percentage of ring substitution, and temperature. Rates of reaction of 1-bromooctane with 17-38% ring-substituted catalysts increased as spacer-chain length increased. Rates of reaction of 1-bromooctane decreased, whether the percentage of ring substitution increased or decreased from 17-19%. Rates of reaction of 1-chlorooctane increased with increasing spacer-chain length and decreasing percentage of ring substitution. Apparent activation energy for the reaction of 1-bromooctane with 9% ring-substituted, spacer-modified catalysts was 9-10 kcal/mol and 13 kcal/mol with 17-19% ring-substituted catalysts. The hydrophilicity of catalysts decreased with increasing spacer-chain length and decreasing percentage of ring substitution. The mechanisms of reaction were discussed in terms of intrinsic reactivity and intraparticle diffusion limitations on the reaction rates.
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  • 50
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3447-3450 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 51
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    Topics: Chemistry and Pharmacology
    Notes: A series of oligomer model compounds of polyethyleneimine derivatives with pendant adenine bases were prepared by the reaction of a carboxyethyl derivative of adenine with oligomeric amines, using an activated ester method. To evaluate the intramolecular interaction between pendant adenine bases in these compounds, ultraviolet spectra at various pH regions were measured. Ultraviolet hypochromicities and pKa values depended linearly on the chain length of the oligomers. The results showed that the intramolecular interactions of adenine bases were realized less in their protonated than neutral forms.
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    Topics: Chemistry and Pharmacology
    Notes: A versatile and high-yielding method was developed for specifically modifying galactose-containing polysaccharides, exemplified here by two representative galactomannans, guar gum 1 and locust bean gum 5. Oxidation of the primary alcohol functions of 1 and 5 with galactose oxidase produced the corresponding aldehyde derivatives 2 and 6 which were subsequently derivatized in several ways. Reductive amination with sodium cyanoborohydride of 2 and 6 proceeded smoothly (60-90% yields) and led to stable amine derivatives (4, 7-11), which included hydroxyalkylamine- (8), glycine- (9), and BSA- (11) derivatives. The cationic primary amine derivative 12 was similarly reductively alkylated with lactose to yield a product 13 with extended carbohydrate side chains. Oxidation of 2 produced the anionic carboxy derivative 14, whereas reduction of 2 and 6 with sodium borodeuteride yielded the deuterium labeled neutral species 15 and 16. The undegraded gums and some of their derivatives were studied by high resolution 13C-NMR (100.6 MHz) at 30°C, and the proposed chemical shift assignments were in good qualitative agreement with those of earlier studies. ESR spectroscopy was used to follow the chemical reactions and to derive information about the galactose distribution of 1 and 5. Mean nearest neighbor distances (r̄) between nitroxides attached to 1 and 5 were 1.36 nm (±5%) for 4 and 1.75 nm (±5%) for 7. These r̄ values agree favorably with the structural models recently proposed elsewhere, excluding earlier suggestions of homogeneous galactose distributions or regularly alternating blocks of branched and unbranched mannose units. The solution properties, such as viscosity and salt- and organic solvent-compatibility, of some of the guar derivatives appear to be unique and interesting. An alternative oxidation procedure of the galactose residues of 1 and 5 with sodium periodate has been evaluated.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1279-1285 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The copolymerization of β-pinene with styrene oxide (SO) and β-pinene with N-vinylpyrrolidone (VP) was investigated by using SnCl4 in dichloromethane diluent at low temperature. Monomer reactivity ratios were evaluated for both copolymers at -80°C; these are r1(SO) = 2.979 and r2(β-pinene) = 0.002 and r1(VP) = 0.096 and r2(β-pinene) = 0.294.
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  • 54
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1287-1298 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Five polyimide films prepared from 3,3′,4,4′-benzophenone tetracarboxylic acid'dianhydride (BTDA) and diamines, 4,4′-oxydianiline (ODA), 3,3′-diaminobenzophenone (DABP), or 3,3′-diaminodiphenylcarbinol (DADPC) and doped with Li2PdCl4 (LTP) or Pd[(CH3)2S]2Cl2 (PDS) were selected for a detailed x-ray photoelectron spectroscopic (XPS) study to determine the oxidation state of palladium and the relative distribution of this and other elements in these films, especially as they relate to electrical resistivity. XPS shows that Pd in the films is present as a mixture of zero and +2 valence states. Films that contain lithium as part of the dopant all show that metal is present as Li+ and Li2O, a fact that may have a bearing on film electrical properties. An Auger electron spectroscopic (AES) or XPS profiling was performed on two of the electrically conductive films. A film doped with PDS reveals a majority of palladium at the surface as Pd(0) and much smaller amounts in film bulk as a mixture of Pd(0) and Pd(II). Film behavior is similar to a metal-vapor deposited film. An LTP doped film, by contrast, exhibits a homogeneous composition with a mixture of Pd(0) and Pd(II). These studies support others that use chemical etching on the film surfaces. Scanning electron microscopy (SEM) has been used to provide surface evaluations.
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  • 55
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1299-1313 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: It is well known that the reaction rate and molecular weight of vinyl polymers can change markedly during the course of polymerization and that these changes are due to the influence of diffusion on the termination reaction. The chain length dependence of the termination rate constant has been considered in this work and has resulted in a general method of treating the polymerization kinetics and molecular weight distribution. This method is independent of the form of the chain length dependency and is capable of dealing with both disproportionation and recombination modes of termination. A specific model for the termination rate constant with chain length dependence is proposed and is based on free volume theory and entanglement coupling. Master curves for the characteristics of the reaction rate and molecular weight distribution are presented with the application of this model.
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  • 56
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1315-1329 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: It is frequently observed that the gel effect in vinyl polymerizations decreases in intensity at about the 50-70% conversion level. This is apparent in both rate and molecular weight data. It is postulated that there should be a limitation on the decrease in the termination rate constant to explain this effect. As an extension of the general theory of chain length dependent termination behavior, a general treatment of the gel effect with a limiting value of the termination rate constant is presented. A specific model is proposed for this limited rate constant which is based on the simple consideration that as translational movement of macroradicals becomes increasingly difficult the contributions made by segmental motion derived solely from the propagation reaction will be the prevailing mechanism. The termination reaction changes from chain length dependent to chain length independent during this transition period.
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  • 57
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1331-1344 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The values of the parameters that are necessary to compute the free volume changes accompanying polymerization were determined from viscosity data of concentrated polymer solutions. Relationships applicable above and below the glass transition temperature of the polymer were quantified. A general treatment of the variation of the propagation rate constant with free volume was postulated, based on the variation of the monomeric diffusivity with free volume. This, in turn, was related to the friction coefficient of a polymer chain segment, the values of which are readily available. A discussion of the reaction behavior in the last stage of polymerization and the occurrence of limiting conversion is also presented.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1345-1371 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bulk polymerization data of methyl methacrylate, ethyl methacrylate, ethyl acrylate, n-propyl acrylate, vinyl acetate, and styrene were compared with the predictions of the theory proposed in the earlier parts of this series (I-III). This theory of polymerization kinetics uses the concepts of free volume and chain entanglements to describe the relationship between chain mobility and chain length dependent termination reactions. Excellent agreement was found between the predictions of the theory and the polymerization rate and molecular weight data of the six polymerization systems studied. Emphasis was placed on the ability to explain the development of higher order molecular weight averages (M̄w, M̄z, etc.) because they provide the most crucial tests for such a model. No changes were required in the model as it was applied to the different polymerization systems for a variety of reaction conditions. The theory offers a unified understanding of the diverse polymerization behavior displayed by such systems.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1373-1387 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The wettability of poly(ethylene terephthalate) films is an important criterion for their industrial use. The attainment of that property is realized by treatment of the material under corona discharge. The purpose of this article is to describe the influence of the principal parameters of the discharge on the modification of the surface properties; the influence was measured by physicochemical methods (ESCA, contact angle). The results prove that the most important physical parameters of the discharge are the wire-cylinder distance, the current intensity, and the time of treatment. The analysis shows that the fixed species are oxygen and nitrogen in the form of carboxylic functions and amines or nitrogen oxides. In any case, the correlation between free surface energy and concentration of fixed chemical species shows that the surface properties depend on the chemical functions introduced into the material by the discharge.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1389-1400 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The interaction of poly(ethylene oxide) with alkali picrates in tetrahydrofuran and dioxane was studied by optical and NMR spectroscopy and conductance measurements. Evidence was found of the formation of two kinds of solvation complex, differing in the nature of the ion pairs involved. A strong anion effect on cation binding to the polyether was demonstrated.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1401-1409 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The copolymerization of methylenedioxolanes, such as 4-methylene-1,3-dioxolane (I) and 2,2-dimethyl-4-methylene-1,3-dioxolane (II), with maleic anhydride (Manh) gives rise spontaneously to the alternating copolymers by the participation of charge-transfer (CT) complexes. The formation of CT complexes I-Manh and II-Manh was ascertained by UV and NMR spectroscopies. The equilibrium constants (K) could not be determined but were assumed to be small (K ≪ 1). For comparison with these systems an investigation of I-dimethyl maleate (DMM) and II-DMM systems was carried out to estimate K values 0.115 and 0.157 L/mol, respectively. To clarify the copolymerization mechanism I-Manh-acryronitrile was terpolymerized. Consequently it was concluded that the spontaneous copolymerization of I-Manh and II-Manh systems is effected by the CT complex monomer mechanism.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1709-1716 
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    Keywords: Physics ; Polymer and Materials Science
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    Topics: Chemistry and Pharmacology
    Notes: Radiation-induced cationic polymerization of styrene was studied in methylene chloride in the presence of triphenylsulfonium hexafluorophosphate. Acceleration in polymerization and an increase in molecular weight at a low temperature (-78°C) were observed in the presence of triphenylsulfonium salt. A study of pulse radiolysis revealed that both effects are due mainly to PF-6, which forms ion pairs with the cationic species involved in the polymerization.
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    Topics: Chemistry and Pharmacology
    Notes: The composition and gross structural features of plasma polymers formed in the glow regions of an inductively coupled RF plasma with perfluorobenzene and perfluorobenzene/hydrogen mixtures were investigated by ESCA as a function of the operating parameters. The carbon-to-fluorine stoichiometries of the perfluorobenzene polymers are similar and close to those of the starting material but not of the polymers derived from perfluorobenzene/hydrogen mixtures. The rate of film deposition is dependent on the W/FM parameter. Angular and photon energy-dependent studies confirm the vertical homogeneity of the plasma polymer films investigated.
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    Notes: An ESCA investigation has been made of the plasma polymers produced from the isomeric tri-, di-, and monofluorobenzenes in inductively coupled plasmas. Comparison is drawn with other published data on perfluoro-, pentafluoro-, and isomeric tetrafluorobenzenes. The data reveal that extensive molecular rearrangement accompanies polymerization and that proportionately the C:F stoichiometry shows a decrease in fluorine content relative to the monomer in going from perfluoro- to monofluorobenzene. Internal stress, critical surface tensions, and coefficients of friction are compared for the plasma polymers.
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  • 65
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1745-1764 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A multiple-correlation analysis program was used to generate equations relating the Alfrey-Price Q and e values of vinyl monomers to the 13C-NMR absorption frequencies of the α- and β-carbon atoms of the monomers. Separate equations for the calculation of Q and e values of styrenes, chlorinated olefins, acrylates, methacrylates, vinyl ethers, and esters, nitrogen containing monomers, allyl compounds, and miscellaneous olefins were developed. The correlation coefficients of most of these equations were greater than 0.99 and permit accurate calculation of the Q and e values. The Q and e values so calculated may then be used to obtain estimates of the reactivity ratios in copolymerizations prior to actually performing the experiments. Attempts to develop a single Q value equation and a single e value equation for 63 vinyl monomers of the above classes resulted in relations having correlation coefficients of 0.63 and 0.81, respectively, too low to permit sufficiently accurate calculation of the Q and e values.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1765-1774 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two addition-type polymers, polystyrene and polypropylene, and two condensation-type polymers, poly(ethylene terephthalate) (Mylar) and poly(hexamethylene adipamide) (nylon-6,6), were pyrolyzed directly in the ion source of a mass spectrometer by chemical ionization (CI) to reduce fragmentation. The spectra are relatively easy to interpret because most ion peaks occur at a mass corresponding to the ion formula M±H or M + 3H, where M is the formula of a fragment of the original polymer chain. Oligomer peaks were observed for the addition-type polymers. The intensities of the protonated dimer and monomer were measured as a function of time for styrene (S) and propylene (P). It was found that essentially all the HS+2 was produced by the reaction of HS+ with S, but at least part of the HP+2 was formed by proton transfer to P2. The absence of the analogous reaction in styrene is presumably a result of the reduced volatility of S2.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1785-1790 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Metal phthalocyanine oligomers that possess peripheral carboxylic acid groups were prepared by the reaction of pyromellitic dianhydride, a metal salt, urea, and a catalyst. These materials have blue to purple colors with a metallic luster and are soluble in sulfuric acid, dimethylsulfoxide, dimethylformamide, and dimethylacetamide. Their thermal stability is high in an anaerobic atmosphere with char yields of 80-85% at 800°C. Elemental, spectral, and titrimetric analyses and thermal studies were carried out to characterize them.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1875-1884 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The laser-initiated polymerization of charge-transfer monomer complexes was investigated with a pulsed nitrogen laser and an argon laser. Several donor-acceptor monomer charge-transfer systems were screened for polymerization in different solvents. Polymerization by laser initiation was achieved in two of these systems; that is, 2-vinylnaphthalene/fumaronitrile and 9-vinylanthracene/fumaronitrile. The best polymer yields were obtained with the 2-vinylnaphthalene/fumaronitrile system in sulfolane solvent. The influences on the polymer yield and composition of solvents, varying focal path length, glass conditioning, initiation sources, environment, and monomer feed ratios were evaluated. Infrared (IR) spectral studies, gel permeation chromatography (GPC), and chemical analyses were performed to characterize the polymer products arising from the polymerization of 2-vinylnaphthalene/fumaronitrile in sulfolane. The polymer contained a high percentage of sulfolane (ca. 1/3 mol fraction), presumably arising from solvent transfer to the growing polymer chains during the propagation phase of the polymerization.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1949-1952 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1947-1948 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1953-1957 
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1959-1963 
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    Keywords: Physics ; Polymer and Materials Science
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    Topics: Chemistry and Pharmacology
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1965-1970 
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    Keywords: Physics ; Polymer and Materials Science
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    Topics: Chemistry and Pharmacology
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1971-1984 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Volume flow of epoxide prepolymers and the effect of compression rate, temperature, and molecular weight on it are described. An increase in longitudinal volume viscosity with decreasing volume deformation, increasing compression rate, and increasing temperature has been observed. The molecular weight seems to have no influence.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1985-1992 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermally stable and semiconducting poly-Schiff bases are synthesized by condensing 4,4′-diacetyl diphenyl ether with o-, m-, and p-phenylene diamines, benzidine, and ethylene diamine under different experimental conditions. These bases are insoluble in common organic solvents. They are characterized by infrared (IR) and viscosity measurements, thermal analysis, and the study of electricel properties at various temperatures. Variation of electrical conductivity σ with temperature followed the empirical relation σ = σ0e-E*/kT.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1993-2006 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Chain transfer constants to monomer have been measured by an emulsion copolymerization technique at 44°C. The monomer transfer constant (ratio of transfer to propagation rate constants) is 1.9 × 10-5 for styrene polymerization and 0.4 × 10-5 for the methyl methacrylate reaction. Cross-transfer reactions are important in this system; the sum of the cross-transfer constants is 5.8 × 10-5. Reactivity ratios measured in emulsion were r1 (styrene) = 0.44, r2 = 0.46. Those in bulk polymerizations were r1 = 0.45, r2 = 0.48. These sets of values are not significantly different. Monomer feed compcsition in the polymerizing particles is the same as in the monomer droplets in emulsion copolymerization, despite the higher water solubility of methyl methacrylate. The equilibrium monomer concentration in the particles in interval-2 emulsion polymerization was constant and independent of monomer feed composition for feeds containing 0.25-1.0 mole fraction styrene. Radical concentration is estimated to go through a minimum with increasing methyl methacrylate content in the feed. Rates of copolymerization can be calculated a priori when the concentrations of monomers in the polymer particles are known.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2033-2041 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The copolymerization of 3,4-dimethyltetrahydrofuran with selected cyclic ethers was studied. Although 3,4-dimethyltetrahydrofuran did not homopolymerize, it readily copolymerized with propylene oxide and epichlorohydrin in an alternating fashion using the cationic initiator PF5. The reactivity ratios r1 and r2 for the copolymerization of 3, 4-dimethyltetrahydrofuran and epichlorohydrin were r1 = 0.22 ± 0.05 and r2 = 0.11 ± 0.01, respectively.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2007-2017 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Amphiphilic block copolymers of 9-vinylphenanthrene (VPh) and methacrylic acid (MA) were prepared by a two-step living anionic polymerization of VPh and trimethylsilyl methacrylate followed by hydrolysis of the trimethylsilyl ester groups. Bis(2-hydroxyethyl) terephthalate, an oxidative quenching agent with amphiphilic nature, strongly quenched the fluorescence of phenanthrene groups in the block copolymer in aquecus solution. Apparent second-order rate constants kq for the quenching ranged in the magnitude of 1011-1012M-1 s-1 in the borate (pH 9) and phosphate (pH 7) buffers, whereas those in DMF solution were found to be ∼109M-1 s-1. No such difference in kq for the aqueous and DMF solutions was observed with the related random copolymer. The results suggest that a considerable increase in the effective concentration of the quencher around the VPh sequences in the block copolymer resulted from hydrophobic association. Fumaric acid (FA), an anionic quencher, did not quench the fluorescence of the copolymer at pH 9 and 7, presumably because of the lack of accessibility of the quencher to the copolymer due to electrostatic repulsion. However, in neat water in which only a part of the carboxyl groups of MA sequences are dissociated and therefore the charge effect is minimized, FA quenched the fluorescence, with the kq value approximating the diffusion control limit.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2169-2179 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: From a great deal of experimental data we obtained an empirical equation for polymer solution fluidity and concentration: \documentclass{article}\pagestyle{empty}\begin{document}$ \frac{{\eta _{{\rm sp}} }}{{c\eta _r }} = [\eta ] - K_c [\eta ]\frac{{\eta _{{\rm sp}} }}{{\eta _r }} $\end{document} This equation is more linear than conventional equations that relate polymer solution viscosity and concentration. The equation of the initial concentration parameter γ is applicable over a wider concentration range: \documentclass{article}\pagestyle{empty}\begin{document}$ \frac{{\eta _{{\rm sp}} }}{{c\eta _r }} = [\eta ] - K_c ^{\prime \prime \prime } [\eta ]\frac{{\eta _{{\rm sp}} }}{{\eta _r^\gamma }} $\end{document}
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2195-2204 
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    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The behavior of the readily available cis- (1) and trans- (2) 4, 5-epoxy-2-pentenals toward classical cationic, anionic, and free radical initiators has been examined. Only the cationic polymerization of 1 gave soluble polymer of moderate molecular weights. This polymer possessed predominantly the cyclopolymerized furanose structure 12. Cationic initiation of 2 and anionic initiation of both 1 and 2 gave only crosslinked materials, and free radical initiators with 1 and 2 gave no polymer.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2205-2213 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The electron transfer between insoluble polymer containing 1-benzyl-1,4-dihydronicotinamide (BNAH) structure (P-BNAH) and benzoquinone (Q) structure (P-Q) by use of alloxan (A) as an electron carrier was investigated. Although no reaction occurred on suspending the P-BNAH and P-Q in ethanol/water, P-Q was reduced smoothly to hydroquinone structure (P-HQ) by addition of A. The results suggest that A was reduced by P-BNAH to give A radical (A·) or dialuric acid (D) and then A· (or D) reduced P-Q, whereby A was regenerated and thus indicated that the oxidation reduction between insoluble solid polymers was mediated by A as an electron carrier.
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  • 82
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of 2(2-hydroxy-5-methylphenyl)-5-vinyl-2H-benzotriazole was accomplished in seven steps starting from 4-ethylaniline. Acetylation and nitration followed by hydrolysis gave 2-nitro-4-cthylaniline which was diazotized, condensed with p-cresol, and reduced to 2(2-hydroxy-5-methylphenyl)-5-ethyl-2H-benzotriazole. As in previous cases, the ethyl group was transformed to the vinyl compound by bromination with N-bromosuccinimide and dehydrobromination of the 1-bromoethyl compound. Monomer grade 2(2-hydroxy-5-methylphenyl)-5-vinyl-2H-benzotriazole was polymerized and copolymerized with styrene, methyl methacrylate, and n-butyl acrylate.
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  • 83
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2249-2258 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The theory that β-ketonitrile structures initiate discoloration reactions in polyacrylonitrile has been tested by a number of methods. Using radiochemical techniques the numbers of carbonyl groups in various polymers have been measured as have the amounts of combined water. A model β-keto compound, 1,3,7,-tricyanoheptan-4-one was synthesized and its reactions studied. None of these experiments supported the idea that β-ketonitrile structures are of primary importance in initiating the degradation of polyacrylonitrile.
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  • 84
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2239-2247 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Crystals of 9-ethyl-3-vinylcarbazole(I) were easily polymerized to high polymer under mechanical shear stress and photoirradiation without initiator. The degree of polymerization was higher for tribo- than for photopolymerization. It was concluded that the mechanism of polymerization was cationic for both polymerizations on the basis of additive effects. The polymerization behavior depended on the recrystallizing solvents. Ethanol crystals are less sensitive to tribo- and photo-polymerization than those of n-hexane or benzene. X-ray diffraction patterns of I also differed, depending on the recrystallizing solvents. The reactive crystals were in a high energy state, as revealed by DSC analysis. Similarities of photo- and tribopolymerization and comparative studies of tribopolymerization with triboluminescence of I indicated that polymerizations are likely to be induced by an identical reactive intermediate tentatively considered as a zwitterionic species.
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  • 85
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2231-2238 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The extent of binding of methyl orange, ethyl orange, propyl orange, and butyl orange by a polyion complex, which consists of equimolar sodium polymethacrylate and a piperidinium cationic polymer, was measured in ethylene glycol at 25, 30, and 35°C. The effects of aqueous and nonaqueous media on the binding of the dye by the polymer matrix were compared. In ethylene glycol only noncooperative binding (Langmuir type) was observed, whereas two modes of binding, noncooperative and cooperative, were involved in the aqueous environment. The first binding constants and the thermodynamic parameters associated with the binding in ethylene glycol were evaluated. The polymer matrix exhibited a higher affinity toward the dye in ethylene glycol than in water at low concentrations of free dye and bound these anionic cosolutes with different hydrophobicities but the same affinity as in ethylene glycol. These interactions are highly exothermic and characterized by relatively large negative entropy changes. Electrostatic forces are the principal contributors to the dye-polymer complex formation. The binding behavior observed in the nonaqueous solvent is reasonably accounted for in terms of disappearance of hydrophobic interactions between the dye and the polymer and an increase in electrostatic attraction between the anionic small molecule and the positively charged sites on the polyion complex.
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  • 86
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2259-2266 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reaction of poly(vinyl chloride) (FVC) with electrogenerated superoxide anion was carried out in a mixed solvent of tetrahydrofuran (THF) and dimethylformamide (DMF), mostly at 40°C, under a nitrogen stream. The results obtained were compared with those in an earlier article,1 in which the use of potassium superoxide was described. Reaction of PVC with electrogenerated superoxide anion took place easily and the yield and molecular weight of the recovered polymer decreased appreciably. Functional groups formed in PVC treated with electrogenerated superoxide anion were similar to those in PVC treated with potassium superoxide; that is, hydroxy (ca. 3400 cm-1), conjugated carbonyl groups (ca. 1675 cm-1), and polyene structures (ca. 1600 cm-1) were observed. In addition, a new peak, probably due to nonconjugated aldehyde groups, was observed at 1725 cm-1. Ultraviolet (UV) spectra of PVC treated with electrogenerated superoxide anion showed that the polyene sequences formed in the polymer were shorter than octaene and that the octaene and that the octaene was formed only in the reaction at 60°C.
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  • 87
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A recently reported method for the synthesis of thermotropic liquid crystalline polymers by the interaction of reactive polymers with mesogenic compounds is further illustrated by the preparation of two mesomorphic polymers. Specifically, poly(acryloyl chloride) is esterified with p-hydroxybiphenyl and p-hydroxyazobenzene for the synthesis of poly(p-biphenyl acrylate) and poly(p-acryloyloxyazobenzene), respectively. The liquid crystalline character of both polymers was established by optical microscopy, x-ray diffraction analysis, and differential scanning calorimetry.
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  • 88
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2461-2476 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Electron paramagnetic resonance (EPR) was used to study a MgCl2-supported, high-mileage olefin polymerization catalyst. Anhydrous Toho MgCl2 was the starting material. Treatment with HCl at an elevated temperature, ethyl benzoate by ball-milling, p-cresol, AlEt3, and TiCl4produced a catalyst that contained a single EPR observable Ti+3 species A, which was strongly attached to the catalyst surface, had a D3h symmetry, and no other Ti+3 ion in an immediately adjacent site. Species A constitutes only 20% of all the trivalent titaniums; the remainder is EPR-silent and may be attributed to those Ti+3 ions that have adjacent sites occupied by one or more Ti+3 ions. Activation with preformed AlEt3/methyl-p-toluate complexes produced a single Ti+3 species (C) with rhombic symmetry and displaying 27Al superhyperfin splitting which has attributes for a stereospecific active site. This species is unstable under polymerization conditions and is transformed to another species with axial symmetry and solubilization. Both processes could lead to catalyst deactivation and loss of stereospecificity. Catalysts activated by AlEt3 and methyl-p-toluate separately in various sequential orders produced a multitude of EPR-observable Ti+3 species with varying degrees of motional freedom deemed detrimental to stereospecific polymerization of α-olefins.
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  • 89
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2477-2499 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Biuret oligomers and polymers from primary aliphatic amines and aromatic or aliphatic diisocyanates have been synthesized. To demonstrate the feasibility of the synthesis of polybiurets, aliphatic primary amines with n-propyl, n-hexyl, n-octyl, and n-dodecyl groups have been incorporated. For the synthesis of biuret oligomers of biologically active primary aliphatic amines [8-(4-amino-1-methylbutylamino)-6-methoxyquinoline] (primaquine) and adamantanamine were selected. Primaquine was also incorporated into polyepichlorohydrin by nucleophilic substitution of the chlorine of the chloromethyl group by the primary aliphatic amino group of primaquine. The structure of the biuret polymers was established by elemental analysis, and by infrared 1H- and 13C-NMR spectroscopic characterization. Several attempts to use primaquine as a diamine for the formation of condensation polymers, including reaction of primaquine with sebacoyl chloride (to form polyamides), or with diisocyanates (to form polyureas) were unsuccessful.
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  • 90
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2693-2703 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: To investigate high-pressure copolymerizations a sampling technique has been developed enabling continual on-line GLC analysis of the reaction mixture. As a result more reliable kinetic data are obtained. This new “sequential sampling” method, allowing the use of gaseous monomers, has been tested for the copolymerization of ethylene with vinyl propionate at 118 MPa and 335 K with tert-butyl alcohol as solvent. The results are compared with those obtained with the “quenching” method used so far, which yields compositional data on the reaction mixture before and after the high-pressure stage, only. It is shown that the “sequential sampling” method is the most adequate method of determining high-pressure monomer reactivity ratios. Furthermore, it is an important safety feature that the present procedure can be easily remote controlled. The present experimental method is neither restricted to copolymerization nor to gas-chromatographic analysis of the reaction mixture.
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  • 91
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2731-2734 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 92
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2727-2730 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 93
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 2(2-Hydroxy-5-isopropenylphenyl)2H-benzotriazole was synthesized in 40% overall yield starting from o-nitroaniline. Diazotization in aqueous hydrochloric acid gave o-nitrophenyl diazonium chloride which was condensed with p-hydroxyacetophenone; the azo compound was reduced to 2(2-hydroxy-5-acetylphenyl) 2H-benzotriazole with zinc powder in sodium hydroxide solution and the 2-hydroxy group of the compound was acetylated. Treatment of the acetyl compound with methyl Grignard reagent resulted in the methylation of the 5-acetyl group to 2[2-acetoxy-5(2-hydroxy-2-propyl)phenyl]2H-benzotriazole which was then dehydrated with potassium hydrogen sulfate to the desired 2(2-hydroxy-5-isopropenylphenyl)2H-benzotriazole. This monomer did not homopolymerize, but was copolymerized readily with styrene, methyl methacrylate, and n-butyl acrylate with azobisisobutyronitrile as the initiator. 2(2-Acetoxy-5-acetylphenyl)2H-benzotriazole was also reduced with sodium borohydride to form 2[2-acetoxy-5-(1-hydroxyethyl)phenyl]2H-benzotriazole which was dehydrated and hydrolyzed to the known 2(2-hydroxy-5-vinylphenyl)-2H-benzotriazole. This route provides a novel and simpler synthesis of 2(2-hydroxy-5-vinylphenyl)2H-benzotriazole.
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  • 94
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2755-2764 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Photopolymerization of styrene was carried out in a dispersed system to obtain 10 μm particles, using d-t-butylperoxide as initiator and poly(vinyl alcohol) as protective colloid. It was shown that particles typical for latex polymerization are also formed and interfere with the dispersion polymerization when excess protective colloid is used.
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  • 95
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2839-2849 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: (2-Chloroethyl)oxirane, (3-chloropropyl)oxirane, and (4-chlorobutyl)oxirane were prepared from the corresponding alkenols and polymerized using a triethylaluminum-water-acetylacetone initiator system. Copolymerizations with propylene oxide and epichlorohydrin were also accomplished; the copolymerization activities of the (chloroalkyl)oxiranes were similar to the activity of epichlorohydrin. Poly[(2-chloroethyl)oxirane], poly[(3-chloropropyl)oxirane], and poly[(4-chlorobutyl)oxirane] exhibit elastomeric properties and are highly reactive in nucleophilic substitution reactions.
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  • 96
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2879-2885 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Relatively high-molecular-weight segmented polyurethanes based on methylene bis(4-phenyl-iso-cyanate), poly(propylene glycol), butane-1,4 diol, and cis-2-butene-1,4 diol have been synthesized and characterized. These unsaturated polyurethanes were successfully grafted using N-vinyl pyrrolidone as monomer and 2,2′-azobisisobutyronitrile as free-radical initiator. However, grafting experiments involving benzoyl peroxide as initiator were unsuccessful. The graft copolymers were isolated from the ungrafted polyurethane and poly(N-vinyl pyrrolidone) by selective solvent extraction. Elemental microanalysis, IR, NMR, thermogravimetric analysis, and equilibrium water sorption measurements were used to characterize the graft copolymers.
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  • 97
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2863-2878 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The formalized kinetic approach to the mechanism of urethane formation in the system of prepolymer with end NCO groups-1,4-butanediol together with the dispersion analysis of kinetic curves have helped to establish that, at moderate temperatures, the mechanism may be represented by a scheme comprising a noncatalytic stage of urethane formation and a catalytic one including the formation of a double complex of a catalyst with an isocyanate or a hydroxyl group. As the temperature rises the proportion of the noncatalytic stage decreases significantly, while a mechanism, including the formation of the triple complex isocyanate group-catalyst-hydroxyl, becomes the most probable. It has been shown that the formation of a triple complex at elevated temperatures is thermodynamically more advantageous than the formation of double complexes; hence these changes of mechanism with temperature. It has been found that the temperature conditions of polyurethane production greatly affect the degree of its branching. Two crosslinked polyurethanes were obtained, one under the temperature conditions providing for the minimum degree of branching, the other under isothermal conditions. It has been discovered that the degree of branching of a prepolymer may greatly affect the density of chemical and physical bonds and a range of physical and chemical properties of the polyurethane.
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  • 98
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2887-2894 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The effect of chlorine, bromine, and iodine at the 3 and 3,6 positions on a carbazole ring with thermodynamic properties, that is, enthalpy, entropy, and a stability constant of CT complex poly(N-vinylcarbazole-2,4,7-trinitrofluorenone), were studied in a temperature range of 268-323 K. The discussion of the results obtained, based on linear free-energy relationships, stressed the advantageous influence of the halogen substituent in the carbazole ring on the properties of the poly(N-vinylcarbazole)-2,4,7-trinitrofluorenone complex.
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  • 99
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2895-2902 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The interaction of triphenylmethyl salts with α-methylstyrene and 1,1-diphenylethylene was investigated. With 1,1-diphenylethylene at a monomer-initiator ratio of 2 (room temperature), mainly 1,1,3-triphenyl-3-methyl-indane was isolated, whereas at a ratio of 100 (-10°C), the dimer 1,1,3,3-tetraphenylbutene-1 mainly formed. In both cases no addition of the trityl group was registered. In the interaction of α-methylstyrene with Ph3C+SbCl6- at a monomer-initiator ratio of 2(room temperature) a pure 1,3,3-trimethyl-1-phenylindane was isolated and no addition of the trityl group to the double bond was recorded. The initiation reaction of α-methylstyrene polymerization by trityl and chlorinated trityl salts was studied at temperatures from -20 to 0°C and different concentrations. The oligomers obtained with (pCI-C6H4)3C+ were investigated by elemental analysis and fluorescence spectroscopy. The presence of Ph3CH in the reaction mixture was demonstrated by GLC and NMR spectra. The results obtained give evidence that the initiation of α-methylstyrene polymerization involves hydride abstraction from the monomer.
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  • 100
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2909-2914 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In our earlier investigations of chemically crosslinked polyethylene and polypropylene we based our interpretation of the properties of these polymers on the compound concentration scale.1-4 To check the validity of this scale we performed some NMR experiments on crosslinked polypropylene and compared the results with the gel scale.
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