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  • 1980-1984  (538)
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  • 1983  (538)
  • Physics  (538)
  • 101
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 269-291 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new method is presented that provides experimental information which is qualitatively and quantitatively sensitive to assumptions made as to the mechanisms of free radical entry and of latex particle formation in emulsion polymerization systems. The method consists of (1) obtaining (by electron microscopy) the full particle-size distributions (PSDs) at several different times soon after the cessation of latex particle nucleation, (2) using these PSDs to determine the volume dependences of the various rate coefficients governing particle growth by fitting the data to the appropriate evolution equations, and (3) employing these empirical rate coefficients to find that time dependence of the nucleation rate which fits the early-time PSD (again using the evolution equations). This method is quite sensitive to mechanistic assumptions: for example, one is able to determine whether or not the nucleation rate is an increasing or decreasing function of time. The technique is applied to a styrene nucleation system employing sodium dodecyl sulfate as surfactant at well above the critical micelle conventration. The data cannot be fitted even qualitatively by a simple one-step nucleation mechanis, whether it involes micellar entry or homogeneous nucleation. It is found, on the other hand, that the results can be accurately fitted by assuming that coagulation events between primary colloidal particles, perhaps formed by homogeneous nucleation, dominate both the nucleation process and the entry of free radicals into mature latex particles. In addition, the data indicate that the rate of free radical entry into the latex particles decreases with increasing particle size, at least for particles of unswollen radius less than ca. 40 nm.
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  • 102
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 329-334 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermoxidative degradation of vinyl acetate/vinyl alcohol statistical copolymers was studied under dynamic thermal conditions and compared with that of block copolymers. The dependence of thermal characteristics or kinetic parameters on the content of —OH groups of copolymers was established.
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  • 103
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 353-364 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 8,9-Benzo-2-methylene-1,4,6-trioxaspiro[4,4]nonane (BMTN) was prepared by the reaction of phthalide with epichlorohydrin, followed by dehydrochlorination. BMTN was polymerized with di-t-butyl peroxide (DTBP) to give a solyble polymer with a high molecular weight and good thermal stability. The infrared (IR) and nuclear magnetic resonance (NMR) spectra indicated that the polymer structure contained aromatic ester and ketone in the backbone. Tg and Tm of homopolymer of BMTN were, respectively, 98 and 282°C. BMTN was also readily copolymerized with such vinyl monomers as methyl methacrylate (MMA), acrylonitrile (AN), and maleic anhydride (MA), but not with styrene, in the presence of radical initiators. AN and MA, in particular, were spontaneously copolymerized with BMTN in the absence of radical initiators at 40°C. From the results of ultra violet (UV) spectra it is suggested that spontaneous copolymerization proceeds via a charge-transfer complex between BMTN as an electron donor and AN or MA as an acceptor.
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  • 104
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 375-384 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A method has been developed for following the bromine and weight losses of fire retarded UPE as a function of temperature. The results obtained by this method indicate that those bromine-containing fire retardants which exhibit a linear LOI-bromine concentration relation, the bromine concentration in the pyrolytically produced fuel remains more or less constant, while for those materials which deviate positively from the linear relation (that is they are more efficient), the bromine concentration in the fuel tends to peak at certain temperatures. When this effect is combined with variation in composition of the pyrolytic fuel, a situation can arise where a high bromine concentration coincides with a fuel particularly sensitive to flame quenching by bromine. Such a combined effect may be the reason why some brominated fire retardants are far more effective than others.
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  • 105
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 407-413 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of polymerization of acrylonitrile(AN) initiated by manganese(III) acetate in the presence of glycerol was investigated in the temperature range of 30-40°C. The effect of varying the concentrations of glycerol, sulfuric acid, acetic acid, metal ion, and monomer on the rate was studied. A suitable reaction scheme and rate expression have been proposed. Termination was mutual and was caused by the combination of two growing polymer radicals.
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  • 106
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 447-455 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A study was made of the formation of polyion complexes between a piperidinium cationic polymer and polyanions and of the binding of azo-dye anions (methyl, ethyl, propyl, and butyl orange) by these complexes. Sodium poly(acrylate), poly(styrenesulfonate), dextran sulfate, and carboxy-methylcellulose were used as polyanions. The resultant polyion complexes (insoluble in aqueous solutions) were compared for their ability to bind the small organic molecules in aqueous solutions, for example, of urea and an inorganic electrolyte (KCI), and exhibited a strong binding affinity toward these small anions. Polyion complexes that consisted of sodium poly(acrylate), dextran sulfate, and carboxymethylcellulose as polyanions cooperated in the binding, whereas the polyion complex of sodium poly(styrenesulfonate) did not. It was suggested that small organic anions interact with the polyion complexes primarily through electrostatic and hydrophobic forces.
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  • 107
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1517-1527 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Photooxidation of leuco crystal violet(LCV) to the dye(CV+) by interfacial sensitization with polymer-bonded pyrenyl groups was studied. Poly(ethylene-g-acrylic acid) was esterified by 1-hydroxymethylpyrene in tetrahydrofuran (THF) (Film 1) or in acetonitrile (Film 2). Film 2 had a more condensed but thinner pyrene-containing surface layer than Film 1. Differences in surface structure were investigated by fluorescence and absorption spectra, as well as by measuring contant angle to water as a function of the total amount of bonded pyrene. Films 1 and 2 behaved differently in the photoreaction, which was interpreted as due to the difference in the affinity of LCV solution to the film surface, hence the diffusion of LCV into the film. The quantum efficiency of CV+ formation (φcv+) is therefore the function of the thickness of the photoabsorbing layer and the effective reaction volume determined by the depth of LCV diffusion. The role of excimer formation and energy migration among pyrenyl groups was concluded to be of minor importance.
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  • 108
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1529-1534 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Three types of polymer electron transfer sensitizer were prepared by copolymerization of 1-pyrenylmethyl methacrylate with styrene (I), vinylbenzyltriethylammonium chloride (II), and sodium p-styrenesulfonate (III). Irradiation of the pyrenyl group in the presence of leuco crystal violet (LCV), in homogeneous or in heterogeneous systems, induced the formation of crystal violet cation (CV+) in air. The reactivity of I, II, and III was in the order of II 〉 I 〉 III in both systems; this was rationalized in terms of the Coulombic effect. The effect of charge is much greater for the heterogeneous systems. High-charge density on the polymer surface and enhanced polymer-solvent affinity account for the high reactivity of II. The high quantum efficiency, coupled with the advantage of facile product separation, warrants the practical application of interfacial sensitization.
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  • 109
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1559-1565 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of γ-benzyl-DL-glutamate NCA in the presence of poly(γ-benzyl-L-glutamate) was investigated. At the initial stage the D-enantiomer was preferentially polymerized (ca. 35% ee) by using triethylamine as an initiator. Enantioselectivity was independent of the molecular weight of preformed poly(γ-benzyl-DL-glutamate).
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  • 110
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A detailed analysis of the reaction products generated by reorganization of polycarbonates with piperazine, performed by direct mass spectrometry methods, has shown that this reaction actually follows the pathway postulated and that, at 50% piperazine incorporation level, urethanediphenol compounds are almost exclusively produced. This allowed us to obtain, by repolymerization with phosgene, alternating copoly(carbonate-urethanes) with thermal stabilities comparable to those of the parent polyurethanes. The primary fragmentation mechanisms in the thermal decomposition of these copolymers were studied by direct pyrolysis into the mass spectrometer. Ester exchange reactions predominate here, causing the formation of cyclic oligomers, which are subsequently cleaved to open-chain oligomers containing hydroxyl end groups.
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  • 111
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This article reports a continuation of our work on the substituent effects on the preferred helical conformations and the mutarotation of substituted poly(L-prolines). The size of the substituent has been increased from a methyl group to an ethyl group in the 5 position. The purpose is twofold: (i) according to our theoretical conformational energy calculations, an ethyl group in the 5 position can exert a greater steric effect than can a methyl group; and (ii) the rotation-isomerization of the ethyl group introduces a new intriguing fact to the problem. The cis isomer of 5-ethylproline was synthesized by catalytic hydrogenation of Δ′-2-ethylpyrroline-5-carboxylic acid, whereas for trans-5-ethylproline, a chemical separation method involving p-toluenesulfonyl chloride was used. The resolution of cis-5-ethylproline and the assignment of absolute configurations have been carried out by fractional crystallization and circular dichroism spectroscopic techniques, respectively. Poly(cis-5-ethyl-D-proline) was obtained from its corresponding N-carboxyanhydrides via a ring opening polymerization.
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  • 112
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1657-1664 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Initiation and propagation processes in thermally initiated solid-state polymerization of sodium acrylate have been studied. The kinetics of initiation, followed with the electron spin resonance technique, leads to an activation energy E of 28.8 kcal/mol, which is attributed to the formation of dimeric radicals. The activation energy of 16 ± 1 kcal/mol obtained for the solid-state polymerization of sodium acrylate by chemical analysis and differential scanning calorimetry has been attributed to the propagation process.
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  • 113
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1693-1698 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Copolymers of p-vinyltrifluoroacetophenone (VTFA) with optically active (-)-menthyl acrylate (MtA) have been prepared by free radical initiation. The values of reactivity ratios (rVTFA = 4.28 and rMtA = 0.26) indicate that counits are inserted substantially at random into the copolymer macromolecules. CD spectra show a couplet typical of exciton splitting in the absorption region of trifluoromethylphenyl (TFA) chromophore. Dependence of ellipticity on composition and sequence distribution suggests that TFA chromophores are in a chiral environment provided by the dissymmetric conformation of the copolymer macromolecules.
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  • 114
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1729-1740 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of solid copolymer of vinylidene chloride and vinyl chloride with aqueous sodium or potassium hydroxide solutions in the presence of quaternary ammonium or phosphonium salts as phase transfer catalysts gave dehydrochlorinated products with chlorine-substituted polyene structure. Among the catalysts used tetrapropylammonium bromide was the best and potassium hydroxide was more active than sodium hydroxide. The activity of quaternary ammonium salts was discussed in terms of hydrophile-lipophile balance. The effects of temperature and the concentration of the bases and catalysts were investigated to obtain the optimum reaction condition. Treatment of the polymer films and solutions in tetrahydrofuran with aqueous bases under two-phase conditions also produced dehydrochlorinated films and powders.
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  • 115
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1751-1761 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two possible conformations for poly(cis-5-ethyl-D-proline) have been identified and characterized by using combinations of 1H- and 13C-NMR, CD, and ORD spectroscopic techniques. Both forms have helical conformations similar to those of poly(L-proline) characterized by different amide bonds (cis and trans). However, the carbonyl group of the amide in poly(cis-5-ethyl-D-proline) form II (trans) seems to be closer to perpendicular orientation with respect to the helical axis than in poly(L-proline) form II. The pyrrolidine ring conformation of form I (cis) is probably β+γ--puckered, whereas for form II it is probably β+-puckered in nature. The side-chain ethyl groups prefer to adopt anti conformations to the C5—H bond, or prefer to have χ = 180°, regardless which of the two forms poly(cis-5-ethyl-D-proline) may like to assume. The experimental results agree well with our previous theoretical conformational energy calculations.
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  • 116
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1773-1783 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Copolymers prepared by the bulk copolymerization of p-t-butylstyrene (S) and methyl methacrylate (M) were analyzed by 1H-NMR. The spectra showed fine structure in the δ 2.2-3.6 region similar to that reported for styrene/methyl methacrylate copolymers. Reactivity ratios for S-M copolymers determined by classical composition measurements differed markedly from the same ratios determined by NMR when it was assumed that NMR peak-triad assignments could be made by analogy with published styrene/methyl methacrylate assignments. A new set of peak-triad assignments was proposed that reconciles this difficulty and gives good agreement between triad fractions measured by NMR and those calculated from theory.
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  • 117
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 637-649 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New active bisamides, 4,4′ -diacylbis-2-aryl-1,3,4-oxadiazoline-5-thiones and -ones having various electron accepting groups in the oxadiazoline units were synthesized, and their reactivities toward diamines were investigated. The polycondensation reactions of the bisamides derived from 2-aryl-1,3,4-oxadiazoline-5-thiones with both aliphatic and aromatic diamines occurred rapidly even at room temperature to form high-molecular-weight polyamides in quantitative yields. The reactivities of the bisamides having electron accepting groups such as p-chloro and p-nitro groups, particularly p-nitro groups, toward diamines were much higher than that of the corresponding bisamide having no such group. It was also found that reaction conditions such as solvent, monomer concentration, and temperature had a strong influence on the molecular weight of the resulting polyamides. Aminolysis of several benzoyl derivatives of 2-aryl-1,3,4-oxadiazoline-5-thiones and -ones was also carried out as a model reaction, and the effect of electron accepting groups on the reactivity of these compounds was discussed.
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  • 118
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 679-689 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The mechanism of flame retardant (FR) action of red phosphorus in polyacrylonitrile combustion was investigated by thermogravimetry, flash-pyrolysis GC-MS, and combustion methods. Red phosphorus was found to increase the thermal stability in air of polyacrylonitrile and to induce a char residue increment on this substrate. Both these effects disappeared when pyrolysis was carried out under nitrogen flow. Flash-pyrolysis GC-MS experiments showed that red phosphorus does not alter the pyrolysis product distribution of polyacrylonitrile, which implies that there is no specific interaction between polyacrylonitrile and red phosphorus. These data also showed that polymeric red phosphorus decomposes to volatile white phosphorus (P4) during pyrolysis. These observations allow us to propose a simple model for the mechanism of FR action of red phosphorus on polyacry-lonitrile at the molecular level. Combustion data for polyacrylonitrile-red phosphorus mixtures are in agreement with the proposed mechanism of FR action.
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  • 119
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1951-1972 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Butadiene is polymerized by cobalt compound-organoaluminum-CS2 catalysts to give highly crystalline syndiotactic 1,2-polybutadiene (s-PB) having melting point up to 216°C. An aluminum-free catalyst, Co(C4H6)(C8H13)-CS2, is also effective. Syndiotactic polymerization with Co(C4H6)(C8H13)-CS2 is not interrupted by the addition of protic substances such as water and alcohol, but is influenced by donor or acceptor substances. The donor molecule, e.g., dimethylsulfoxide or dimethylformamide, decreases the stereoregularity, i.e., syndiotacticity and 1,2 content. An acceptor molecule of organoaluminum with appropriate acidity such as AlEt3-AlEt2Cl or tetraethylaluminoxane increases the molecular weight, stereoregularity, and yield of the polymer. In the presence of CS2 a mixture of cis-PB and s-PB was obtained by using Co(octoate)2-AlEt2Cl-H2O, with molar ratio H2O/Co less than unity. In the case of H2O/Co 〉 1, only cis-PB was obtained. By the addition of donor substances such as ester, ether, nitrile, and AlEt3, s-PB was obtained even when H2O/Co 〉 1. The amount and ratio of cis-PB and s-PB are dependent upon the nature and amount of the additives.
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  • 120
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1989-1995 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A mechanism is proposed for the polymerization of syndiotactic 1,2-polybutadiene (s-PB) with soluble cobalt-organoaluminum-CS2. The proposed active species have structures which consist of side-on coordination of CS2 to cobalt, anti-π-allyl growing end, cisoid bidentate coordination of butadiene, and activation by complex formation with organoaluminum at the nonbonded sulfur of the coordinated CS2. This proposal is based on findings for the aluminum-free catalyst Co(C4H6)(C8H13)-CS2. It is tentatively interpreted that syndiotactic 1,2 polymerization proceeds under the influence of the side-on coordinated CS2, by which the reactivity between the terminal carbons of butadiene and the C3 of the π-allyl end is enhanced.
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  • 121
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2003-2010 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The error-in-variables model (EVM) is a mathematical description of experiments in which there is error in all measured variables. This contrasts with ordinary least-squares methods in which it is assumed that error is only present in the dependent variable or variables. EVM leads to statistical procedures which are able to obtain more efficient estimates of unknown parameters from data with error in all the variables than can be obtained by using least-squares methods. One type of experiment to which EVM is applicable is the measurement of copolymer reactivity ratios. It has been applied recently to the binary case, but the only known method for estimating reactivity ratios in ternary systems is that of Rudin et al. which is based on ordinary least squares. The application of EVM to the problem is described in this article and the results are compared with those of Rudin et al.
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  • 122
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2025-2045 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Novel photosensitive polymers with pendant photosensitive group, such as cinnamic ester, and photosensitizer groups, such as N-carbamoyl-p-nitroaniline and N-carbamoly-4-nitro-1-naphthylamine, were synthesized from radical copolymerizations of (2-cinnamoyloxy)ethylmethacrylate with photosensitizer monomers, such as p-nitrophenylmethacrylamide and 4-nitro-1-na-phthylmethacrylamide, by using asobisisobutyronitrile (AIBN) in benzene and from the copolymerizations of (2-hydroxy)ethylmethacrylate or (2-hydroxy)ethylacrylate with photosensitizer monomers by using AIBN in DMF. This procedure was followed by condensation reactions of the copolymers with cinnamoyl chloride with pyridine as HCL acceptor in the same reaction flask. The photoreactivities of the polymers obtained were influenced by the concentration of photosensitive group and photosensitizer groups and their ratio in the polymer matrix. In addition, the photosensitivity of cinnamic ester groups attached to a soft polymer segment was higher than that of cinnamic ester group attached to a hard polymer segment when these polymers had the same pendant N-carbamoyl-p-nitroaniline group as photosensitizer. Furthermore, the spacer length between the polymer chain and photosensitizer group was important for increasing the photoreactivity of the photosensitive group in the polymers with pendant cinnamic ester and N-carbamoyl-p-nitroaniline groups.
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  • 123
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2101-2109 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of vinyl monomer initiated by an aqueous solution of poly(vinylbenzyltrimethyl)ammonium chloride (Q-PVBACI) was carried out at 85°C. Styrene, p-chlorostyrene, methyl methacrylate, and i-butyl methacrylate were polymerized, whereas acrylonitrile and vinyl acetate were not. The effects of the amounts of vinyl monomer, Q-PVBACI, and water on the conversion of vinyl monomer were studied. The overall activation energy in the polymerization of styrene was estimated as 79.1 kJ mol-1. The polymerization proceeded through a radical mechanism. The selectivity of vinyl monomer was discussed by “a concept of hard and soft hydrophobic areas and monomers.”
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  • 124
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2095-2100 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Starch-g-polyacrylonitrile (starch-g-PAN) copolymers were prepared by ceric ammonium nitrate initiation, and the major portion of the starch in these graft copolymers was then removed by acid hydrolysis to yield PAN with oligosaccharide end groups. Although these PAN-oligosaccharide samples reacted with methyl methacrylate in the presence of ceric ammonium nitrate, the resulting products were largely graft copolymers rather than the expected PAN-poly(methyl methacrylate) (PMMA) block copolymers. The following evidence is presented for a PAN-g-PMMA structure: (i) PAN without oligosaccharide end groups also produced a copolymer with methyl methacrylate under our reaction conditions. (ii) Starch-g-PAN (51 or 37% add-on) was a less reactive substrate toward ceric-initiated polymerization than PAN with oligosaccharide end groups. (iii) Low-add-on (18%) starch-g-PAN reacted with methyl methacrylate to give a final graft copolymer in which a large percentage of PMMA was grafted to the PAN component rather than to starch.
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  • 125
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2145-2155 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Rates of decomposition of di(3-hydroxybutyl)-2,2′-azobisisobutyrate, di(4-hydroxybutyl)-2,2′-azobisisobutyrate, di(2-hydroxyethyl)-2,2′-azobisisobutyrate, di(2-chloroethyl)-2,2′-azobisisobutyrate, and di(2-hydroxypropyl)-2,2, all of which are useful in the polymerization of butadiene and isoprene, were measured by nitrogen evolution technique at 60, 70, and 80°C, respectively, in each of the three solvents, namely, toluene, dioxane, and N,N-dimethylformamide. The thermal decompositions of these azo compounds in solution were first order, and the Arrhenius equation was used to calculate their activation energies.
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  • 126
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2162-2162 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 127
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2197-2202 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The dependence of the polymerization rate and average chain length on the absorbance of the initiator in the photoinitiated polymerization of vinyl monomers has been evaluated. It is found that a simple model taking into account the spatially inhomogeneous free-radical distribution predicts an order in initiator that changes from 0.5 at low concentration to -0.5 at high concentration. The maximum rate is obtained, irrespective to any other condition, when the absorbance of the initiator is 2.51.
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  • 128
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2203-2214 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cationic, ring-opening copolymerization of 1,6-anhydro-2-azido-3,4-di-0-benzyl-2-deoxy-(2-ABG), -3-azido-2,4-di-0-benzyl-3-deoxy- (3-ABG), -4-azido-2,3-di-0-benzyl-4-deoxy-β-D-glucopyranose (4-ABG) with 1,6-anhydro-2,3,4-tri-0-benzyl-β-D-glucopyranose (LGTBE) was investigated with phosphorus pentafluoride as catalyst at low temperatures, giving highly stereoregular, (1→6)-α-linked copolymers with number-average molecular weights of 3.90 × 104-9.27 × 104. Structure and composition of the copolymers were determined by 1H- and 13C-NMR spectroscopies and elemental analysis, which indicated that copolymerization occurred in a stereoregular manner to give azido groups containing (1→6)-α-linked glucopyranan derivatives. The differences in polymerizability among the three azido monomers are discussed. Regioselective reduction of three kinds of heteropolysacharide derivatives which had different quantities of azido groups at C-2, -3, or -4 position with lithium aluminum hydride and subsequent debenzylation of the copolymers with sodium in liquid ammonia produced amino-group-containing heteropolysaccharides.
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  • 129
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2345-2362 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The ring-opening polyaddition reaction of anti and syn head-to-head Coumarin dimers with diamines and the photocleavage behavior of the resulting polyamides were investigated. Anti head-to-head Coumarin dimer successfully reacted with aliphatic and aromatic diamines in an aprotic polar solvent to give corresponding high molecular weight polyamides. The polyamides showed good film forming ability and exhibited solubility behavior typical of polyelectrolytes. Furthermore, these polyamides were found to undergo exclusively asymmetric photocleavage on the cyclobutane rings in the polymer main chain to give a fumaramide unit with elimination of 2,2′-dihydroxystilbene. On the other hand, syn head-to-head Coumarin dimer gave only low molecular weight polyamides. These polymerization and photocleavage behaviors were elucidated in comparison with those of model reactions.
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  • 130
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2363-2382 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Vinyl acetate (VAc)-butyl acrylate (BuA) comonomer mixtures with various composition were polymerized by batch and semicontinuous emulsion polymerization processes. PVAc and PBuA homopolymer latexes as well as the (VAc-BuA) copolymer latexes were characterized with respect to particle size, molecular weight, acid end groups on particle surfaces, and colloidal stability against electrolytes. The surface and colloidal properties of these latexes were also compared before and after aging and acid hydrolysis. The average particle size of batch latexes was independent of copolymer composition, whereas for semicontinuous latexes it decreased with increasing BuA content and was always lower than that of the corresponding batch latex. The molecular weight distribution (MWD) for batch latexes was narrower and much less dependent on composition than that of the semicontinuous latexes; bimodal MWD was found in most semicontinuous latexes with a substantial amount of low MW fraction. The total weak and strong acid end groups on particle surfaces for semicontinuous latexes is higher, and more dependent on composition, than the batch latexes. Acid-induced hydrolysis results in a drastic change in the type and concentration of the surface groups of the semicontinuous latex particles. Colloidal stability against electrolytes showed that both electrostatic (due to surface acid groups) and steric [due to surface poly(vinyl alcohol)] mechanisms are contributing. However, for semicontinuous latexes, increasing PVAc content above 50 mol % resulted in a proportional increase and ultimately dominant role of steric stabilization. The results were interpreted in terms of differences in reactivity ratios and water solubilities of the two monomers and their effects on the locus of initiation and growth in the two polymerization processes, as well as the monomer sequence within the polymer chain and degree of homogeniety of the copolymer composition within the particle.
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  • 131
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1165-1171 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The Kelen-Tüdös linear graphical method was used to determine the copolymerization parameters of some halogen-substituted (e.g., Cl, Br, I) aniline monomers. It was found during copolymerization with p-aminobenzoic acid or p-aminophenol that the reactivity of these monomers followed the order of their basic strength. The order of their basic strength. The order of their reactivity, however, was reversed if they copolymerized with sulfanilic acid (SA). This reversal has been interpreted in terms of the resonance stabilization of monomers, the nature of the acidic functional groups present in the comonomer, and the influence of electron-accepting or electron-donating groups present in the comonomers.
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  • 132
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1183-1193 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cis-trans isomerization of polybutadiene double bonds during metathesis degradation using WCl6/(CH3)4Sn catalyst system has been estimated kinetically along with productive metathesis. The isomerization was followed both for noncrosslinked and for crosslinked polybutadiene. Ninety-six percent cis-1, 4 units are found to isomerize into ca. 75% trans-1, 4 units. The rate of stereomutation is found to be different in the presence and absence of a low-molecular-weight olefin. The results are explained with the help of a stereo model originally proposed by Katz (Advances in Organometallic Chemistry, Academic, New York, 1977, Vol. 16.)
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  • 133
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2559-2571 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The effect of reaction conditions on conversion and molecular weight in the polymerization of butadiene initiated by cobalt octoate/diethylaluminum chloride/water was studied. The polymerization exhibited complex kinetics with respect to cobalt concentration. The molecular weight, as a function of conversion, was investigated. Chain transfer to aluminum alkyl was of only minor importance.
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  • 134
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2573-2580 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A study was made of the ceric-ammonium-nitrate-initiated graft polymerization of methyl methacrylate (MMA) onto a lineal fraction of starch (amylose). Grafting yields were determined by extraction with appropriate solvents: 1,2-dichloroethane for homo-PMM, and 0.5N NaOH for ungrafted amylose. Percent grafting was calculated by acid hydrolysis with 1N HCl. Molecular weights of PMMA side chains were determined by gel permeation-chromatography. Grafting efficiencies ranged from 72 to 83%, grafting, from 190 to 271%, and frequency of attachment of side chains, from 900-1250 glucose units per chain. The results observed are discussed.
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  • 135
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2589-2596 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The direct method of radiation grafting was used to cover poly(methyl methacrylate) tubes and rings with a thin layer of poly(acrylic acid) hydrogel. The copolymer formed is used as a support for covalent immobilization of enzymes. The enzyme support coupling was realized with carbodimide or glutaraldehyde. The activity of the immobilized chymotrypsin and peroxidase was determined and the stability of the enzyme-linked copolymers was tested.
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  • 136
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2629-2648 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Head-to-head polyisobutylene of molecular weight 3000 to 10,000 was prepared in about 30% yield by Grignard coupling polymerization of 2,2,3,3-tetramethyl-1,4-dibromobutane with copper(I) tris(triphenylphosphino)bromide as the catalyst. Head-to-head polyisobutylene is crystalline, with a Tm of 187°C and a Tg of 87°C and still has bromine end groups left. The polymers have been characterized by their infrared, 1H-, and 13C-NMR spectra and compared to the corresponding head-to-tail polymers of similar molecular weight. A substantial portion of the reaction product of the Grignard coupling polymerization is not polymeric but was identified as cyclized product, 1,1,2,2-tetramethylcyclobutane.
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  • 137
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2665-2674 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The aqueous polymerization of methyl methacrylate (MMA) initiated by potassium persulfate (I)-thiomalic acid (TMA) redox couple has been studied at 30 ± 0.2°C under nitrogen atmosphere. The rate of polymerization is given by \documentclass{article}\pagestyle{empty}\begin{document}$$ R_p = K[{\rm MMA}]^{0.98} [{\rm K}_2 {\rm S}_2 {\rm O}_8]^x [{\rm TMA}]^{0.44} $$\end{document} up to 20.0 mmol/L TMA concentration, where x = 0.52 for the I concentration 0.6-10 mmol/L and x = 0.27 for higher I concentrations. The temperature had a marked effect on initial rate and maximum conversion. The overall energy of activation was found to be 11.79 kcal/mol (49.31 kJ/mol). Injection of more initiator (I) at intermediate stages enhanced both the initial rate and maximum conversion. Ag (I) and Fe (III) depressed initial rate as well as maximum conversion, while Cu (II) activated the polymerization. The effect of solvent was also studied.
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  • 138
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2697-2711 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1,4-cis-polymerizations of 1,3-dienes of TiCl4-AIR3 catalyst systems for isoprene and on TiI2Cl2-AIR3 caltalyst systems for butadiene have been investigated. AIR3 denotes herein an organoaluminum compound (OAC) containing hydrocarbon radicals, linear of different lengths or cyclic, both saturated and unsaturated, as well as those containing O, N, or Si atoms. Neither the OAC radical structure nor the Al/Ti ratios in the range investigated have been found to influence the stereospecificities and reactivities (chain propagation constant) of the active centers. Differing activities of the catalyst systems have been established to result from the variations in the concentrations of the active centers involving 〈1-5% of all the Ti species. The nature of the OAC radical does not change the mode of the molecular weight distribution in the polymers obtained. An increase in the molecular weight (MW) of the polydienes produced with the use of higher-MW trialkylaluminums was provoked by an increase in the macromolecules propagation period owing to the lower constant of chain transfer to the higher-MW OAC.
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  • 139
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2739-2748 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactivity ratios for the free-radical copolymerization of methyl methacrylate with ethyl acrylate in the presence of low concentrations of ZnCl2 are analyzed at different polymerization temperatures, 35,50, and 65°C. The different tendencies of the two monomers toward the formation of molecular complexes with the metal halide modify the homopropagation and cross-propagation coefficients and the results obtained seem to indicate a conventional cross-propagation mechanism in which both free and complexed species of acrylic monomers participate.
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  • 140
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1331-1345 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reaction of sulfinylaminobenzoyl chlorides with lead thiocyanate gave sulfinylaminobenzoyl isothiocyanates (SBIs), from which were derived aminobenzoyl isothiocyanate hydrochlorides (ABIHs). AB polyacylthioureas (PATUs) with inherent viscosities of up to 0.28 dL/g were obtained by treating the SBI with an equivalent of water in N-methyl-2-pyrrolidone (NMP). Low-temperature solution polyaddition of the ABIH afforded AB PATU with inherent viscosities of up to 0.66 dL/g, which were further increased to as high as 0.75 dL/g by adding lithium bases to the polymerization mixtures. Polyaddition of isophthaloyl diisothiocyanate with intermediate diamines formed by hydrolyzing the adducts of SBI and aromatic diamines afforded copolyacylthioureas with inherent viscosities of up to 1.15dL/g. The copolymers were generally soluble in NMP, whereas solubilities of the AB PATU in analogous solvents were relatively low. Thermogravimetric analyses in both air and nitrogen exhibited weight losses of 5% at 204-236°C for AB PATU and at 170-192°C for the copolymers.
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  • 141
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2675-2682 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermal conversion of polyhexazocyclanes and compound modeling the fragments of polymers were explored within 300-600°C under vacuum (10-5 torr) and in water vapor. At temperatures below 450°C, the hydrolytic degradation plays a key role in the thermal degradation of polyhexazocyclanes. At a higher temperature, the homolytic processes prevail, water, strongly retained by the macroheterocycle, is most important in the hydrolysis process. It was shown that the increase in the thermohydrolytic stability of polymers with the system of condensed cycles in the macroheterocycles and that of polyhexazocyclanes modified by polymer analogous conversion at the secondary amino groups of the isoindole cycle was caused by the absence of bound water.
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  • 142
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2713-2725 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Acrylonitrile was terpolymerized with styrene and 2,4,6-tribromophenyl acrylate in aqueous emulsion and dimethylformamide solution. Experimental terpolymerization data agreed well with calculations based on the Alfrey-Goldfinger equation. Triangular coordinate graphs show the feed/terpolymer relationships; the lines of unique and binary azeotropic compositions were identified. No points of true azeotropic composition were found but a “pseudo-azeotropic” region was recognized. The experimental data of the emulsion terpolymerization experiment agreed well with the theoretical curves over a wide range of monomer compositions up to high conversions. Incorporation of 2,4,6-tribromophenyl acrylate in the terpolymer decreased the thermal stability but improved the flame retardancy of the terpolymers.
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  • 143
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2755-2762 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of 12-alkyl tricosanes (four compounds) was examined by use of 13C nuclear magnetic resonance at 62,89 MHz as model compounds for isolated short- and long-chain (C5, C6, C7, C8) branches in low-density polyethylene and ethylene-α olefin copolymers. An array of 13C resonances was observed and we note that the 13C chemical shifts became insensitive to branch length with octyl and longer branches at this field.
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  • 144
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2987-2995 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A polyion complex was formed from poly(acrylic acid) (PAA) and poly(4-vinylpyridine) (PVP). Its structure and composition were examined by means of infrared spectroscopy (IR), x-ray photoelectron spectroscopy (XPS), and elemental analysis. The polyion complex was obtained by dissolving PAA and PVP together in methanol. The composition of the polyion complex was independent of stirring speed, mixing sequence, and standing time after mixing. However, the composition depended on the concentrations and the ratio of the components in the reaction mixture. Excess of PAA in the product was observed when concentrated solutions (2.0 × 10-1M) were used for the preparation or when an excess of PAA was added to PVP. The sorption of water vapor by an equimolar PAA/PVP complex at 293 and 303 K was higher than that by the pure components, especially in the low- and middle-pressure regions. In the high-pressure region, however, the uptake was not affected by the complex formation. While hydrogen bond interactions in general decrease sorption, Coulombic interactions between polymer chains increased the sorption capacity.
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  • 145
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2845-2861 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The morphology of polybutylacrylate-polystyrene (PBA-PS) core-shell latex particles prepared by seeded emulsion polymerization was investigated as a function of the addition method of styrene (St). The thin layer chromatography/flame ionization detector (TLC-FID) technique was used to characterize the morphology of the core-shell latexes. It was found that grafting PS to the PBA core occurs during seeded emulsion polymerization. The percentage of grafting depended on the method of addition of St, being greatest for the batch reaction, less for the preswollen batch reaction, and least for the semibatch reaction. Upon aging the PBA core-polymer migrated out of the latex particles with a low degree of grafting to form dumbellshaped particles, whereas the PBA-PS core-shell particles with a high degree of grafting remained spherical because of the emulsifying ability of graft copolymer.
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  • 146
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    Topics: Chemistry and Pharmacology
    Notes: The mechanism of imidazole catalysis in the curing of epoxy resins was studied using the PGE/1-methylimidazole, 2-methylimidazole, and 1,2-dimethylimidazole model systems and another model system based on trichloromethylethylene oxide. It was demonstrated that imidazolium systems, generated in the curing reaction, show an inherent instability leading to cleavage of an N—C bond or the 2-C—H bond (2-unsubstituted imidazoles). Fourier-transform infrared spectroscopy was used to follow specific changes in the IR spectrum of the curing mixture during polymerization. The identification of carbonyl absorptions occurring during the polymerization led to the conclusion that ketone formation is a general occurrence in the cure of epoxides with nitrogen compounds. We have also shown that imidazoles are regenerated during the curing process by at least two routes. One pathway for the regeneration of the catalyst involves N-dealkylation of the imidazole via a substitution process. Another route, β-elimination, afforded carbonyl compounds, which account for the previously unexplained appearence of infrared bands in the 1650-1770 cm-1 region during the curing process. These investigations demonstrated the true catalytic function of the imidazole. Possible mechanisms for the regeneration of the catalyst are also suggested.
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  • 147
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1535-1542 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Catalytic hydrolysis of enantiomeric substrates by N-decanoyl-L-histidine was studied at pH 7.30, 0.02M phosphate buffer, and 25°C in the presence of quaternized polymers. The rate of reaction is remarkably accelerated in the presence of polyethylenimine derivatives, but the observed stereoselectivity depends on the structure of the substrates.
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1557-1557 
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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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  • 149
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1551-1555 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 4 Ill.
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  • 150
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1567-1581 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The primary fragmentation mechanisms in the thermal decomposition of several polycarbonates were studied by direct pyrolysis into the mass spectrometer. Our results indicate that ester exchange reactions predominate in the primary thermal fragmentation process of polycarbonates, causing the formation of cyclic oligomers.
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  • 151
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 3269-3279 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Various termination models in the radical copolymerization are compared on the basis of available experimental data for the dependence of the initial rate of copolymerization on the composition of the monomer mixture. A diffusion-controlled model seems to be more adequate for the majority of reported data than a chemically controlled one. The potential effect of activity coefficients in calculations of the initial rate of copolymerization is discussed.
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  • 152
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 3303-3312 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The radical copolymerization of phenyl, ortho-chlorophenyl, and para-chlorophenyl acrylates with methyl methacrylate has been studied at low conversions. The reactivity ratios of these comonomeric pairs have been determined by the application of Fineman-Ross and Kelen-Tudös methods, and the inherent reactivities of phenyl acrylate derivatives toward methyl methacrylate radicals seem to be related to their availability of forming π complexes with methyl methacrylate. The scheme Q-e for these systems clarifies that the higher the polar factor e of the phenyl acrylate derivative, the higher reactivity of the corresponding monomer. The stereochemistry of the prepared copolymers has been studied by NMR spectroscopy. In the analysis of the α-CH3 resonance signals, considering methyl-methacrylate-centered triads, it becomes apparent that the introduction of ring aromatic substituents in the copolymer chains changes appreciably the tacticity of poly(methyl methacrylate).
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  • 153
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 3313-3320 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Alkyl substitution in a series of main chain, liquid crystal polyesters strongly depressed their glass temperatures, melting points, clearing points, and mesophase thermal stabilities. Polymers with pendant n-alkyl substituents eight carbon atoms or longer did not form a liquid crystal phase.
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  • 154
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 3241-3247 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The direct polycondensation reaction of diphenyl chlorophosphate (DPCP) as a new condensing agent in pyridine was used for the preparation of polyarylene esters. High-molecular-weight polymers can be prepared by reacting a pyridine solution of dicarboxylic acids and DPCP in the presence of LiCl, followed by treating with a pyridine solution of bisphenols. About an equivalent of LiCl, and 30 mol % excess of DPCP were most favorably added. Effects of the initial reaction of the acids and DPCP, and of dropwise addition of bisphenols on the polycondensation were investigated. Polycondensations of several hydroxybenzoic acids were also carried out with limited success.
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  • 155
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1699-1715 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An optically active polypeptide, poly(trans-5-ethylproline) (PT5EP) was synthesized and its solution properties were observed to investigate the conformational changes with various conditions. The trans-5-ethyl substitution on polyproline showed noticeable perturbed effects on the conformations of the polypeptide as well as mutarotation of the polypeptide in solution. Circular dichroism (CD) spectra suggested that the polypeptide existed in a poly(L-proline) form-I-type helix and mutarotated slowly to an intermediate conformation in which some of the amide bonds had rotated to a trans conformation. In trifluoroethanol (TFE) solution the polymer took more than 20 days to change from a form-I-type helix conformation, in which CD bands for D-PT5EP are at 199.5 ± 1.0 (positive), 115.5 ± 0.5 (negative), and around 238 nm (positive), to an intermediate conformation. Upon addition of trifluoroacetic acid (TFA) to a TFE solution, the polymer was transformed to form-II-type polymers. Even a greater change in conformation was observed in a solution of TFA or in LiClO4-TFE. The overall change of the intensity ratio RCD of positive to negative CD bands of D-PT5EP was from 0.6-0.7 to 30. Reverse mutarotation toward the original form I was observed when n-butyl alcohol, water, or THF was added to a solution containing the form II polymer. A blue shift of the UV spectra and a change in the NMR spectrum also supported the concept of this conformational change.
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  • 156
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1717-1727 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Attempts were made to copolymerize p-aminostyrene, p-acetamidostyrene, N-methyl-p-aceta-midostyrene, N-(4-vinylphenyl) phthalimide, N-vinyl succinimide, and N-vinyl phthalimide with methyl acrylate complexed with ethyl aluminum sesquichloride. Only reactions involving N-(4-vinylphenyl)phthalimide and N-vinyl phthalimide yielded alternating copolymers. N-vinyl succinimide gave nonalternating copolymers insoluble in common solvents and the other monomers did not copolymerize. In some cases, the conventional radical copolymers were prepared for comparison purposes. The reactivity ratios of the free-radical initiated copolymerization of methyl acrylate (I) with N-(4-vinylphenyl)phthalimide (II) were r1 = 0.14 and r2 1.56. The alternating copolymers were studied by 1H-NMR and 13C-NMR spectroscopy. The alternating copolymer of N-(4-vinylphenyl)phthalimide with methyl acrylate was hydrazinolyzed to form the alternating copolymer of methyl acrylate with p-aminostyrene. Hydrazinolysis of the alternating copolymer of methyl acrylate with N-vinyl phthalimide removed the phthalimide moiety and generated vinyl amine units which readily cyclized with neighboring methyl acrylate units to form copolymers that contained five-membered lactam rings. The infrared (IR) spectra of the hydrazinolyzed products contain bands due to amine or amide groups and are devoid of the characteristic bands of the phthalimide ring.
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  • 157
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 3517-3524 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 2-Vinyl pyridine (2-VP) can be initiated by a charge-transfer complex formed by the interaction of aliphatic amines such as n-butylamine (nBA) and carbon tetrachloride (CCl4) in a solvent like NN-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). This article describes the polymerization of 2-VP by n-butylamine (nBA) in the presence of carbon tetrachloride in DMSO at 60°C. The rate of polymerization Rp increases rapidly with carbon tetrachloride (CCl4) up to a concentration of 3.93 mol/L, but for a higher concentration it is almost independent of the carbon tetrachloride concentration; Rp is proportional to [nBA]0.5 and [2-VP]1.5 when [CCl4]〉[nBA]. The average rate constant k is 1.03 × 10-5 L/mol s. When [CCl4] 〈 [nBA] the rate constant in terms of [2-VP] was 1.06 × 10-5 s-1 at 60°C and the overall rate constant was 1.035 × 10-5 L/mol s at 60°C.
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  • 158
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis and chain extension of polyisobutylene having nonfluxional terminal cyclopentadiene groups is described. The fluxional behavior of silylcyclopentadiene end groups was previously found to prevent Diels-Alder dimerization of the end groups. The incorporation of a propyl moiety between the silicon atom and the cyclopentadiene ring was found to prevent this fluxional isomerization. Polyisobutylene was synthesized having 3-cyclopentadienylpropyldimethylsilyl end groups with a functionality near 2.0. While thermal extension at 80°C resulted in threefold molecular weight increase, coupling with bisdienophiles yielded greater than tenfold molecular weight increases. The retro-Diels-Alder reaction of coupled end groups prevents the attainment of high-molecular-weight polymers at equilibrium.
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  • 159
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 3601-3605 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 160
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2397-2404 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Elastomeric ionene-TCNQ salts with favorable electrical, mechanical, and processing characteristics were drawn mechanically. The electrical conductivity parallel and perpendicular to the drawing axis was investigated. Correlation between anisotropic conductivity and the change in microstructure was discussed. The resistivity ρ at 25°C of the simple salt (EI-TCNQ0) and the complex salt (EI-TCNQ0.5) were on the order of 105 and 102 Ω cm, respectively. In the drawn TCNQ salts, the ρ parallel to the drawing axis increased greatly; on the other hand, the ρ perpendicular to this axis increased slightly or was similar to the ρ of the undrawn TCNQ salts. The anisotropy in the ρ of EI-TCNQ0.5 between the two directions reached 40 times. The activation energy also increased in the direction parallel to the drawing axis. In the undrawn TCNQ salts, the continuous conduction paths exist isotropically. With drawing, the continuous conduction paths, particularly in the direction parallel to the drawing axis, break or make a structural change. The anisotropic conductivity disappeared with time in EI-TCNQ0; however, it was present in EI-TCNQ0.5 even after 200 days under ambient conditions.
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  • 161
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2427-2438 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The methoxy 1H-NMR assignments in the 2.1-3.7δ region for styrene/methyl methacrylate copolymers have been assessed in terms of pentad sensitivity. Several of the methoxy resonances suggested by this study differ from literature assignments. The evidence in support of these reasignments is based on a comparison of calculated and observed triad distributions and on the good agreement of the value of the reactivity ratio rM calculated from individual triads with that obtained by classical methods. A new procedure for the determination of the tacticity coefficient σ is applied.
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  • 162
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2463-2472 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A number of poly(acrylic acid)-co-nylon graft copolymers were prepared. Two approaches were used. The first involved the direct, radiation-induced grafting of acrylic acid onto the nylon, while the second involved the hydrolysis of polyacrylonitrile-co-nylon graft copolymers. All the resulting poly(acrylic acid)-co-nylon graft copolymers coupled large amounts of protein when the carbodimides CMC and EDAC were used as coupling agents. However, when the enzymes β-galactosidase and trypsin were immobilized, the retention of activity was relatively low. A number of reasons for this effect can be postulated, some of which were investigated. From the evidence, it would appear that the major reason is that the carboxylic acid groups are fixed to a “rigid” backbone, which allows them to interact with the enzyme after the establishment of an initial covalent attachment. Additionally, with acid phosphatase, it was observed that the enzyme interacted with immobilized carboxylic acid groups before coupling occurred.
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  • 163
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2503-2511 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The effects of pressure, irradiation dose rate, and emulsifier concentration on the rate of polymerization of styrene emulsions stabilized with a nonionic surfactant, Teric GX13, were investigated. Results differed from those previously obtained with anionic surfactants and did not follow Smith-Ewart kinetics. The controlling influence of the surfactant at the particle-water interface on the reaction was demonstrated and results could be interpreted in terms of the Medvedev equation. Using this equation, we determined a value for the activation volume for chain propagation, ΔV#p, as -18.7 cm3 mol-1. This value is the same as that for pure styrene and emulsions that follow Smith-Ewart kinetics.
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  • 164
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2535-2546 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The decomposition of polybromostyryl carbanions (PBS-), obtained by anionic polymerization of 4-bromostyrene in tetrahydrofuran (THF), was investigated in the dark in a temperature range of -6--21°C. It was accompanied by the evolution of bromine anions and by the formation of polymeric allylic carbanions (λmax = 575 nm; εmax = 6800 eq-1·L·cm-1). The reaction mechanism was elucidated. The rate constant of the unimolecular rate-determining step of the process was 1.3 × 10-5 s-1 and 9.7 × 10-5 s-1 at -21 and -6°C, respectively. Its apparent energy of activation Eapp = 18.38 Kcal/mol. The polybromostyrenes with allylic carbanions at their ends may decompose further. Their “dark” decomposition yielded 1,3-butadiene-1,3-diphenyl-macromers. The mechanisms of decomposition of the PBS- carbanions and the dark decomposition of the polybromostyryl allylic carbanions are analogous. The rate constant of the latter process was 2.5 × 10-6 s-1 at -6°C. The anionic polymerization of prepared macromers can be initiated in THF at -78°C by α-methylstyryl carbanions, which do not react, however, with PBS- carbanions. “Comblike” polymacromers were prepared in which each branch had a molecular weight of about 50,000. The overall molecular weight of the polymacromer was estimated to be about 1 × 106. It has been assumed that the 2-1 mode of addition to the diene group of the macromer is predominant during its polymerization. The 3-4 mode of addition followed by proton shift represents the termination step. The 4-3 mode of addition was ruled out on the basis of spectroscopic evidence.
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  • 165
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2601-2605 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 166
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Overall rates for the free-radical copolymerization of methyl methacrylate with ethyl acrylate in the presence of low concentrations of ZnCl2 have been determined at 50°C. The rate of copolymerization Rp depends on both the ZnCl2 concentration and the monomer feed composition. Relative copolymerization rates Rp/R0p where R0p is the rate of copolymerization in the absence of complexing agent in the reaction mixture, show a minimum for intermediate feed compositions, independently of the ZnCl2 concentration. On the basis of the results obtained, a conventional copolymerization mechanism is proposed for this system in which free and complexed species of both acrylic monomers participate.
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  • 167
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2787-2812 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of acetylene polymerization initiated by Ti(OBu)4/4AlEt3 catalyst was studied by radioquenching with C*O to count the number of active sites [C] and by CH3OT* to determine the total metal polymer bonds [MPB] and M̄n of the polymer. The amount of quenching agent and time of reaction required and the kinetic isotope effect for CH3OT* were determined. The effects of Al/Ti ratio, catalyst aging, catalyst concentration, temperature, and monomer pressure on the polymerization were investigated. Detailed kinetic data on the variation of rate of polymerization, Rp, [C] [MPB], and M̄n with time were obtained at 298 and 195°K. The results required the assumption that the catalytic species C, is initially active and within less than 30 min all are converted by bimolecular kinetics to a far less active species. Analysis of the data yielded rate constants of propagation and termination and their energies of activation. Estimates of chain transfer efficiency were obtained. The mechanisms for the propagation, termination, and transfer processes were discussed. By drawing on our earlier EPR results we propose probable structures for the catalytically active species.
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  • 168
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 3083-3092 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The influence of chemical structure on the response of aromatic polyesters to high-energy ionizing radiation was studied. Systematic variations of polymers related to poly(ethylene terephthalate) were subjected to γ radiation, and the competitive chain scission and crosslinking reactions were determined by measuring changes in intrinsic viscosity and molecular weights. It was found that an increase in the paraffinic glycol segment of polyterephthalates facilitated crosslinking, while the protective nature of aromatic groups was demonstrated by modifying the dibasic acid segments. The influence of substituents on the terephthalate moiety was mixed: electronegative groups led to chain scission (as evidenced by decreased viscosities), but electropositive substituents exerted a stabilizing effect on polymer viscosity. In almost all cases, number-average molecular weights were decreased by exposure to γ radiation, regardless of viscosity behavior. Crystalline melting temperatures of the polymers generally were decreased by the combined radiation effects of chain scission and crosslinking.
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  • 169
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 25-30 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The radical polymerization of diallyl ether (DAE) with sulfur dioxide produced soluble copolymers whose composition was between 1:1 and 2:1 in SO2. The overall rate was maximum at a 2:1 feed composition in SO2. A cyclocopolymerization scheme, which was based on cross propagations and the intramolecular cyclization of DAE radical, was applied. The energy of activation was larger for the uncyclized DAE radical in undergoing the cross propagation with SO2 than in undergoing the intramolecular cyclization with the pendent allylic group by 40 kJ/mol. Formation of rings made of DAE and SO2 and 3,4-disubstituted-tetrahydrofuran rings by the cyclized DAE units on the main chain was proposed on the basis of the 1H-NMR spectra.
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  • 170
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 67-71 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The curing of an acetylene-terminated polyphenylene resin (Hercules H-Resin) was followed by thermal expansion measurements. This approach proved useful in optimizing the curing conditions of the resin. Curing the polymer in air led to the formation of carboxyl groups, whereas curing under nitrogen did not. The thermal expansion coefficient is a minimum (32 ppm deg-1) for a cure cycle of 250°C for 30 min, followed by 350°C for 30 min. Heating at temperatures above 350°C led to degradation of the crosslinked polymer and an increase in the thermal expansion coefficient.
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  • 171
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 397-405 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Anionic solution polymerization of bicyclic oxalactam, 8-oxa-6-azabicyclo[3.2.1]octan-7-one (abbreviated as BOL), at 25°C yields the polyamide with both carbonyl and imino groups at the axial positions in the tetrahydropyran ring. On the other hand, the polyamide obtained by bulk anionic polymerization of BOL at 100°C has more complicated structures, probably due to the isomerizations and side reactions. The most frequent isomerization of the polyamide was the transfer of the carbonyl group adjacent to the tetrahydropyran ring from the equatorial to the axial position in the presence of base or acid catalyst at 25°C. Mechanisms are discussed from the viewpoint of the characteristic bonds in the polyBOL chain.
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  • 172
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 425-433 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of methyl methacrylate (MMA) initiated by an enolizable ketone (R1—CO—CH2—CO—R2)-carbon black system was investigated. Although enolizable ketone itself could not do so, the polymerization of MMA was initiated by enolizable ketone in the presence of carbon black. In addition, a chloranil-enolizable ketone system was able to initiate the polymerization of MMA. It was found that the enol form of the ketone and quinonic oxygen groups on the carbon black surface played an important role in the initiation system; namely, it was considered that the polymerization was begun by the ketone radical (R1—CO—CH—CO—R2) formed by a one-electron transfer reaction from enolate ion to quinonic oxygen groups. The effect of solvent on the process was also studied. The rate of the polymerization increased, depending on the solvent used, in the following order: benzene 〈 1,4-dioxane 〈 dimethyl sulfoxide 〈 N,N-dimethylformamide 〈 N-methyl-2-pyrrolidone. Furthermore, it became apparent that during the polymerization poly(methyl methacrylate) was grafted onto the carbon black surface (grafting ratio was ca. 40% when benzene was used as solvent) and the carbon black obtained gave a stable colloidal dispersion in organic solvent.
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  • 173
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 487-511 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The oxidative degradation of aliphatic, aromatic, and secondary polyurethanes was investigated over a range of temperatures of 440-1000°C as a function of time and oxygen concentration. The degradation was studied with special emphasis on HCN-evolution; its rate constants and Arrhenius equations were determined. In some of the temperature ranges reactions were diffusion controlled. At relatively low temperatures the oxidative rate constant was a linear function of oxygen concentration, whereas at higher temperatures oxidation of the evolved HCN took place in passage through the hot zone of the furnace; in addition, at these higher temperatures thermal degradation of the polymers and thermal decomposition of HCN in the hot zone occurred simultaneously with oxidation to an appreciable extent. The kinetics and mechanism proposed and quantitatively evaluated account well for the experimental results.
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  • 174
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 541-556 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The optical properties of poly(vinylamine) containing optically active (+)- or (-)-2-(thymin-1-yl) propionyl groups as grafted pendants (PT) and the related monomer (MT) and dimer models (DT) were investigated by UV, circular dichroism (CD), and NMR spectroscopy. Highly syndiotactic PT has a smaller hypochromicity versus MT and a larger optical rotation than the less syndiotactic PT in various solutions. These results are attributed to an interaction between the configurational arrangement of thymines, the conformation of the polymers, and base stacking between thymines. The interactions of these polymers with poly(adenylic acid) (polyA) were also studied and the results compared with other vinyl-type nucleic acid model polymers. The isomers of the optically active dimer models [prepared from meso and (dl)-2,4-diaminopentane] were separated. The CD spectra of (+)-D(-)T in CHCl3 and trifluoroethanol (TFE) displayed extremely solvent-dependent exciton coupling of the π-π* (B2u) transition of the base chromophore, which was not observed in the other models or polymers, except the meso-type dimer model (meso)-D-(-)T. This coupling decreased with increasing solvent dielectric constant, while UV hypochromicity increased. This behavior as well as the 360-MHz NMR spectra suggest that (+)-D(-)T exists in an extended form in solvents of low dielectric constant and gradually assumes a stacked conformation as the dielectric constant increases.
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  • 175
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 589-597 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal reactions of pure metal(11) 4,4′,4″,4′″-phthalocyanine-tetracarboxylic acids of copper, cobalt, and nickel at 350-400°C in vacuum have been studied using Fourier transform infrared spectrometry, gas chromatography, and mass spectrometry. Based on these observations, novel in situ reactions for the synthesis of heat-resistant phthalocyanine “sheet” polymers are described. The poly(metal phthalocyanine) polymers of copper, cobalt, and nickel so synthesized have been characterized by elemental analysis, infrared spectroscopy, and dynamic thermogravimetric analysis. The most noteworthy property of these polymers is their extreme resistance to heat in an anaerobic atmosphere and their high char yields (89-93%) at 800°C in a nitrogen atmosphere.
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 615-621 
    ISSN: 0360-6376
    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 21 (1983), S. 623-626 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 178
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 651-670 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The dissolution process and some solution properties of cellulose in mixtures of liquid ammonia (NH3) and ammonium thiocyanate (NH4SCN) are discussed. The mole fraction ratio of NH3, NH4SCN, and H2O which dissolve cellulose were determined. The effect of temperature on several solution properties was also examined. The temperature coefficient d In [n]/dT for the limiting viscosity number [n] has a value of -1.58 × 10-2 °C-1. This is considered to be rather large but is, in fact, a common occurrence for almost all cellulose derivatives in solution. The values for the Huggins constant K′ showed no systematic trends with temperature. They did, however, suggest the presence of considerable association of the cellulose in solution. Miscibility results of adding the cellulose solutions to organic liquids are also reported.
    Additional Material: 14 Ill.
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  • 179
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 671-677 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A two-phase polycondensation reaction was used to prepare high molecular weight linear poly-(amino-s-triazine)s from aminodichloro-s-triazines and diamines. These polymers contain a high concentration of melamine-type units in the polymer backbone. Molded specimens exhibited good mechanical properties and resistance to organic solvents. Dimethyl substitution at the exocyclic amino group led to a significant reduction in indentation resistance, strength, and modulus.
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  • 180
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 985-997 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The results are reported of studies on the kinetics and the time evolution of the particle size distribution in seeded styrene emulsion polymerization systems wherein the seed latex particles were highly swollen with monomer as a result of prior swelling by dodecane. Conditions were such that no new latex particles were formed nor was a significant number of monomer droplets present (“Interval III”). The data were fitted to obtain values for the rate coefficients for entry and exit (desorption) of free radicals. It was found that, during the early part of the polymerization (when the polymer:monomer ratio in the latex particles is considerably less then in an equivalent emulsion polymerization system without dodecane), the entry rate coefficient was much smaller than that measured in systems without dodecane. This effect is consistent with an entry mechanism wherein entering free radicals must displace surfactant molecules from the latex particles.
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  • 181
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1045-1052 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A study was made of interpolymer complex formation between polyvinylpyrrolidone (PVP) and poly(ethylene oxide) (PEO) with phenolic polymers (PPF) in an acetone-methanol mixture by several methods; for example, viscosity, potentiometry, conductometry, turbidity, and precipitate (complex) weight. A distinct stepwise complex formation between PVP and phenolic polymers was observed by these methods. As in polycarboxylic acid, however, PEO formed a 1:1 complex with phenolic polymers. Some of these observations have been interpreted in terms of the structure of the polymers, preferential solvation of the component polymers, and the probable change in conformation of the complex molecules in mixed solvents.
    Additional Material: 4 Ill.
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  • 182
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This article describes the synthesis and characterization of a new macromer, polyisobutenyl methacrylate (PIB-MA), its free-radical homopolymerization and copolymerization with methyl methacrylate (MMA) to afford the graft copolymer poly(methyl methacrylate-g-isobutylene) (PMMA-g-PIB), the characterization of these polymers, and some physical-mechanical (stress-strain) measurements of the graft copolymer. The key intermediate toward the synthesis of the target macromer was the preparation of polyisobutenyl chloride PIB-Clt by the minifer technique. As shown by 1 H-NMR spectroscopy, and independently by IR spectroscopy coupled with M̄n determination, the PIB-MA macromer carries one terminal methacrylate function per polyisobutylene chain. The free-radical homopolymerization of PIB-MA to very high-molecular-weight product was achieved in bulk at 60°C. The free-radical copolymerization of PIB-MA with MMA also occurs readily and is a convenient route to PMMA-g-PIB. The reactivity of PIB-MA is almost identical to that of MMA; however, in highly viscous systems its rate of diffusion to the reaction site is reduced.
    Additional Material: 5 Ill.
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  • 183
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1075-1083 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ortho-nitrobenzyl cholate esters have been successfully used as photosensitive components in solution inhibition deep UV photoresists. The photochemical behavior of a variety of substituted o-nitrobenzyl cholate derivaties has been examined and resist sensitivity is related to the quantum yield of the reaction. The most efficient system examined is o, o′-dinitrobenzyl cholate/P(MMA-MMA), where the quantum yield of photoreaction is 0.2 and resist sensitivity is ca. 150 mJ/cm2 for a 1.5 μm film. The mode of resist behaviour on irradiation and development is also reported.
    Additional Material: 4 Ill.
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  • 184
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1085-1096 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The tacticity of poly(methyl methacrylate) (PMMA) samples made by emulsion polymerization (EP) has been determined by NMR spectroscopy at higher resolution than any previous study. When photoinitiation is employed at room temperature, the polymer obtained is highly syndiotactic and more stereoregular than that obtained in homogeneous radical polymerization under the same conditions. The percentage of racemic dyads and the length of racemic sequences vary significantly with the degree of conversion and the temperature, but not with variation of the hydrophobic or the hydrophilic part of the detergent molecules. A magnetic field of 5 kG or less accelerates the polymerization reaction and increases the polymer molecular weight when dibenzyl ketone is employed as oil-soluble photoinitiator, and has an indirect influence on the polymer tacticity. From measurements of the temperature dependence of the polymer steric composition, the difference of activation enthalphy and entropy of the meso and racemic additions have been calculated. The values do not follow the correlations from precedent literature for radical polymerization in solution if the reaction is considered a first-order Markov process. The persistence ratio p depends on the detergent and the temperature of the EP; in some cases its difference from unity exceeds the experimental error. These results are interpreted as a conformational effect of the locus of the polymerization in the first stage of the EP (when micelles are present) that favors the racemic addition more than is expected in a homologous solvent such as an alkane, e.g., at the same temperature.
    Additional Material: 3 Ill.
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  • 185
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1139-1149 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: α-Methylene-N-methylpyrrolidone (α-MMP) was synthesized and homopolymerized by bulk and solution methods. The poly(α-MMP) is readily soluble in water, methanol, methylene chloride, and dipolar aprotic solvents at room temperature. Thermogravimetric analysis of poly(α-MMP) showed a 10% weight loss at 330°C in air. The kinetics of α-MMP homopolymerization and copolymerization were investigated in acetonitrile, using azobisisobutyronitrile (AIBN) as an initiator. The rate of polymerization Rp could be expresed by Rp = k[AIBN]0.49[α-MMP]1.3. The overall activation energy was calculated to be 84.1 kj/mol. The relative reactivity ratios of α-MMP (M2) copolymerization with methyl methacrylate (r1 = 0.59, r2 = 0.26) in acetonitrile were obtained. Applying the Q-e scheme led to Q = 2.18 and e = 1.77. These Q and e values are larger than those for acrylamide derivatives.
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  • 186
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1159-1164 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A convenient and practical synthesis of trimethylamine acrylimide, 1, starting from 1, 1, 1-trimethylhydrazinium p-toluenesulfonate, 3, and 3-chloropropionyl chloride is described. The intermediate, trimethylamine 3-chloropropionimide, 2, is easily transformed into 1 either through a single-step dehydrohalogenation or through a two-step process consisting of very facile thermal rearrangement to 1,1,1-trimethylacrylylhydrazinium chloride, 4, and subsequent deprotonation. Two new polymerizable monomers, 5, and 6, containing aminimide functionality were synthesized from trimethylamine imine, 7, and the appropriate vinyl oxazolones, 8, and 9. Synthesis of hitherto unreported trimethylamine chloroacetimide, 10, which offers unique opportunities for incorporating water-solubilizing and alkali-stable aminimide functionality into a variety of structures through nucleophilic displacement, is also described.
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  • 187
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1217-1221 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
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  • 188
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1203-1215 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of high-molecular-weight substantially alternating copolymers of alkyl acrylates with optically active α-olefins is reported. “Induced optical activity” on the side-chain ester chromophores, depending on the chemical structure of the chiral α-olefin, is indicated by CD measurements. Data are reported supporting the conclusion that this induced optical activity is related to a preferential chiral conformation of the macromolecules due to a cooperative effect.
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  • 189
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1239-1239 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 190
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1273-1280 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The Silk fibers of the mulberry (Bombyx Mori) were dissolved in a 70% lithium thiocyanate solution. Dissolved silk was regenerated by casting the films from the solution after dialyzing. The films were investigated by infrared (IR) spectroscopy and x-ray diffraction analysis. It was found that the freshly prepared film was amorphous. The transformation to the β-form could be brought about by heating, solvent induced crystallization, ultraviolet (UV) radiation, and prolonged storage. The mechanism of this transformation is discussed.
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  • 191
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1315-1329 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Laser-initiated polymerization of charge transfer monomer complexes has been investigated using an argon ion laser. The influence of solvents, monomer feed ratio, and irradiation time on the copolymer yield and composition was evaluated. The polymer yield was found to be directly proportional to the irradiation time and the molar concentration of maleic anhydride in the monomer feed. An enhanced rate of polymerization was obtained by substituting electron donating groups in the donor monomer. Polymerization, initiation, and propagation mechanisms, via charge transfer complexes, have been discussed. Comparison of laser-induced polymerization with UV-induced polymerization suggests that laser initiation is an energy-efficient process.
    Additional Material: 8 Ill.
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  • 192
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1347-1359 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Styrene was copolymerized with [(2-methacryloyloxy)propoxy]-trimethylsilane (2-MAPTMS), [(2-methacryloyloxy)propoxy]-dimethylphenylsilane (2-MAPDMPS), and [(2-methacryloyloxy)-propoxy]-diphenylmethyl silane (2-MAPDPMS) in toluene at temperatures between 60 and 90°C using azobisisobutyronitrile (AIBN) as initiator. The compositions of the copolymers were determined by silicon estimation. The reactivity ratios were calculated by the Kelen-Tüdös method. The reactivity ratio r1 (styrene) is higher for styrene-2-MAPDPMS than for the styrene-2-MAPDMPS and styrene-2-MAPTMS copolymerzation system. The difference between the activation energies E11 - E12 favors self-propagation of the polystyryl radical, whereas the ratio of preexponential factors A11/A12 favors cross propagation. For the 2-MAPTMS radical, the difference E22 - E21 favors cross propagation but the ratio A22/A21 favors self-addition. The intrinsic viscosities and the theramal behavior of the copolymers were also studied.
    Additional Material: 8 Ill.
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  • 193
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1385-1400 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of photopolymerization reactions of acrylamide initiated by copper (II)-bis(amino acid) chelates with amino acids glutamic acid, serine, or valine were studied at 30°C. The extent of monomer conversion increases with increased initiator concentration and falls off after reaching a maximum. Analysis of the results shows that for lower concentrations of the initiator, the rate of monomer disappearance is proportional to light absorption fraction fε1/2[monomer] and the square root of the intensity. At higher concentrations of the initiator, the rate of monomer disappearance is proportional to Fε/[initiator]1/2; the monomer exponent is 1.5 and the intensity exponent 0.5. Mutual termination of the radicals is proposed at lower concentrations of the initiator; at higher concentrations of the initiator termination of the initiator radical by the copper (II) complex along with mutual termination occurs. The initiator radical species is identified from flash photolysis studies of these complexes as the Cu(I)-coordinated radical. The effect of pH on the monomer conversion is explained. The data indicate a free-radical mechanism of polymerization and a reaction scheme is proposed for the polymerization reactions.
    Additional Material: 5 Ill.
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  • 194
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1423-1433 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Methoxymethylstyrene (MSt), (2,2-dimethyl-1,3-dioxolan-4-yl)methoxymethylstyrene (MMSt), and (2-ethyl-2-methyl-1,3-dioxolan-4-yl)methoxymethylstyrene (EMSt) were synthesized and homopolymerized and copolymerized. The photochemical behavior of resultant homopolymers and copolymers with methyl methacrylate (MMA) and styrene (St) were investigated. The infrared (IR) and ultraviolet (UV) spectra of poly(MSt) showed that new bands ascribed to methyl benzoate residue increase rapidly with irrdiation time in air, but no detectable changes are observed in vacuum. The solubility measurements of poly(MSt) indicate that the main factor in crosslinking is the direct coupling of the benzyl radical generated by UV irradiation, which was confirmed by photopolymerization of MMA by means of benzyl methyl ether. It was also found that copolymers of MMSt or EMSt with MMA or St are easily crosslinked by UV irradiation. From the results of solubility measurements of these copolymers irradiated both in air and in vaccum, it was concluded that not only the 1,3-dioxolane structure but also the benzyl methyl ether structure takes part in photocrosslinking, as we expected.
    Additional Material: 8 Ill.
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  • 195
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1491-1504 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(vinyl chloride) (PVC) plasticized with a phthalate ester was photodegraded with both farultraviolet (λ mainly 254 nm) and near-ultraviolet (λ 〉 280nm) light. Multiple changes in the infrared spectra of the films were thus induced. The PVC underwent oxidation, dehydrochlorination, and simultaneous chain scission and crosslinking. Some of the phthalate ester was split along the aliphatic side chains, leading to lower-molecular-weight analogs, while a further fraction became firmly bound to the crosslinked part of the PVC. Reaction sequences to account for this complicated series of changes are suggested.
    Additional Material: 13 Ill.
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  • 196
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1505-1516 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Pure metal(II) 4,4′,4″,4′″-phthalocyanine tetraamines (MPTA) have been used to cure epoxy resins in a homogeneous reaction. Infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analytical studies were used to characterize these materials and to evaluate the optimum curing conditions. Considerable improvement in the heat resistance of the epoxy resin cured with MPTA over those cured with other commonly used curing agents was observed. This was expected from the highly aromatic structure of the phthalocyanines. A noteworthy feature of these cured materials is their high anaerobic char yield, 73.5-75%, higher than in any heretofore known cured epoxy systems. Preliminary mass spectral studies on the cured polymers are presented.
    Additional Material: 7 Ill.
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  • 197
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1543-1550 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Metals may be chemically incorporated into organic lithographic resists that contain or can be functionalized with —OH groups. A wide range of metal incorporation (0.04-12% of total solids by weight) has been demonstrated for AZ-1370 (Shipley), a diazo-type photo- and electron resist. The novolac component of the resist is reacted with an organometallic halide, RyMX (R = alkyl, aryl; M = transition or main group metal; X = CI, Br; 1 ≤ y ≤ 4, depending on M) to introduce the corresponding organometallic function into the resist.
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  • 198
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1558-1558 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 199
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1583-1598 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The primary fragmentation mechanisms in the thermal decomposition of several polyurethanes were studied by direct pyrolysis into the mass spectrometer. Ester exchange reactions predominate in the primary thermal fragmentation process, causing the formation of cyclic oligomers, which are subsequently cleaved to open-chain oligomers containing hydroxyl end groups.
    Additional Material: 7 Ill.
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  • 200
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1627-1642 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The size distributions of a number of different polycondensations with nonself-condensing monomers were calculated by a kinetic method. The results of linear polycondensations with and without reversibility or stoichiometry and of multifunctional polycondensations are exactly the same as those obtained by Flory with probability methods and do not differ, when comparable, from the size distributions produced by the polycondensation of self-condensing monomers. Size distributions were also obtained for reactions in which the order of reaction changes with conditions or during reaction. These results clearly show that a Flory distribution is obtained as long as the principle of equal reactivity applies at any given instant, although this reactivity may vary in the course of the reaction.
    Additional Material: 7 Ill.
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