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  • Physics  (429)
  • 201
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 999-1014 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis and polymerization of representative acrylic-type esters containing a terminal acetylene group, CH2=C(R)COO(CHR′)m—C≡CH, where R and R′ are H and CH3 and m = 1 or 2, by anionic initiation to linear polymers are described. In contrast, crosslinked polymers were formed when radical and cationic initiators were used. Crosslinked polymers were also obtained with organolithium compounds but not with sodium naphthalene and sodium benzalaniline; this observation is discussed and compared to the behavior of the acetylenic acrylic esters which do not contain a terminal acetylenic hydrogen. The unpolymerized acetylenic bonds in the resulting linear polymers were shown to be present by infrared spectroscopic methods and by the following post-reactions of these bonds: (1) the heat- and radical-initiated crosslinking of the polymers through the acetylenic bonds; (2) the post-bromination of the acetylenic bonds; and (3) the reaction of decaborane with the acetylenic bonds. The anionic copolymerization of acrylonitrile and styrene with these acetylenic monomers were performed and compared to the copolymerizations with 1-acryloxy-2-butyne and 1-methacryloxy-2-butyne. Dibromination of the linear polymers affords self-extinguishing polymers, while decaboronation yields soluble polymers which do not soften up to 300°C. The linear polymers may be classified as “self-reactive” polymers which yield thermosetting polymers.
    Additional Material: 5 Tab.
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  • 202
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1107-1111 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Data for the azobisisobutyronitrile-initiated polymerization of methyl methacrylate in dilute benzene solution is presented at 80, 100, and 126°C. in terms of Tobolsky's limiting conversion kinetics. Number-average molecular weights were obtained viscometrically. Attempts to evaluate the relative amounts of combination and disproportionation in the chain-terminating reaction were foiled by the discovery that under the conditions reported the initiator efficiency is temperature-dependent decreasing markedly with increasing temperature.
    Additional Material: 1 Tab.
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  • 203
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1083-1099 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Radical polymerization of 4-vinylpyridine (4-VP), 2-vinylpyridine (2-VP), and 2-methyl-5-vinylpyridine (MVP) was studied in concentrated DMF solutions of ZnCl2, ZnBr2, ZnI2, Zn(CH3COO)2, and Cd(CH2COO)2 at 50°C. Polymerization of 4-VP and MVP was accelerated by the addition of the metal salts, while the polymerization of 2-VP was greatly retarded. The sequence of the accelerating effect of metal salts for 4-VP was in the following order: Cd(CH3COO)2 〉 ZnCl2 〉 Zn(CH3COO)2 〉 ZnBr2 〉 ZnI2. This sequence is almost the same as that reported in a previous report for MVP. However, the order was reversed for the retarding effect on the polymerization of 2-VP. At the intermediate concentration of metal salts, polymerization of 4-VP proceeded heterogeneously, which was explained by considering crosslinking of poly-4-VP by the metal ion. Since a linear correlation between the rate Rp and the degree of polymerization was observed for the 4-VP-Zn(CH3COO)2 system, the accelerating effect was postulated to be due to the enhancement in kp. Results of copolymerization of VP with styrene as M2 in a concentrated solution of Zn(CH3COO)2 indicated the strong activation of 4-VP by complex formation (r1 = 2.7 ± 0.5, r2 = 0.08 ± 0.03), whereas the change in the monomer reactivity of MVP is smaller (r1 = 2.0 ± 0.2, r2 = 0.35 ± 0.05). The behavior of 2-VP was abnormal (r1 = 3.35 ± 0.3, r2 = 0.55 ± 0.15, then r1r2 〉 1), which was attributed to the steric effect by complex formation. Solid complexes formed between pyridine, 4-VP, 2-VP, or MVP and zinc salts were prepared as samples for infrared spectroscopy. The shifts in infrared absorption bands of these amines were studied by comparing the infrared spectra of the amines before and after the complex formation, and the results were interpreted in terms of electronic as well as steric interactions of metal salts with ligands. Conjugation of the metal salt with the ligand π-orbitals was necessary to explain both infrared spectra and polymerization results.
    Additional Material: 7 Ill.
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  • 204
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1233-1243 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: α-Methylvinyl isobutyl and methyl ethers were polymerized cationically and the structure of the polymers was studied by NMR. Poly(α-methylvinyl methyl ether) polymerized with iodine or ferric chloride as catalyst was found to be almost atactic, whereas poly(α-methylvinyl isobutyl ether) polymerized in toluene with BF3OEt2 or AlEt2Cl as catalyst was found to be isotactic. In both cases, the addition of polar solvent resulted in the increase of syndiotactic structure as is the case with polymerization of alkyl vinyl ether. tert-Butyl vinyl ether was polymerized, and the polymer was converted into poly(vinyl acetate), the structure of which was studied by NMR. A nearly linear relationship between the optical density ratio D722/D736 in poly(tert-butyl vinyl ether) and the isotacticity of the converted poly(vinyl acetate) was observed.
    Additional Material: 9 Ill.
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  • 205
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1245-1264 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis and the anionic polymerization of representative substituted styrenes, CH2=CH—C6H4R′, where R′ is an ethylenic or acetylenic group attached directly or indirectly to the benzene ring, to linear polymers is described. In contrast, crosslinked polymers were obtained when radical and cationic initiators were used. The unpolymerized, unsaturated bonds in R′ in the resulting linear polymers were shown to be present by infrared spectroscopic methods and by the following post-reactions of these bonds: (1) the thermal- and radical-initiated crosslinking of the linear polymers through the unsaturated bonds in R′; (2) the post-bromination of these unsaturated bonds; (3) the post-copolymerization of these unsaturated bonds with vinyl monomers; and (4) the reaction of decaborane with the acetylenic bonds. The anionic copolymerizations of methyl methacrylate, acrylonitrile, and styrene with these monomers were performed and confirmed their behavior as substituted styrenes. Block copolymerizations with styrene and methyl methacrylate were also performed and the expected results obtained. Post-bromination of the linear polymers afforded self-extinguishing polymers. The linear polymers and copolymers may be classified as “self-reactive” polymers which yield thermosetting polystyrenes.
    Additional Material: 9 Tab.
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  • 206
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1279-1287 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1,4,5,6,7,7-Hexachloro- and hexabromobicyclo-[2,2,1]-5-heptene-2-carboxylic acid vinyl esters have been prepared by esterification of the Diels-Alder addition products of hexachloro- and hexabromocyclopentadiene with acrylic acid. These monomers have been copolymerized with acrylonitrile to yield flame-retardant polymers. Copolymers having a chlorine content up to 18.35% or a bromine content up to 6.35% burn, but copolymers containing 25.0% or more of chlorine or 9.83% or more of bromine do not support combustion.
    Additional Material: 3 Tab.
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  • 207
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    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1307-1312 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A mechanism for radical formation from aromatic sulfinic acids through the disproportionation reaction is suggested. It is postulated that two parallel steps, one a bimolecular reaction and the other involving a trimer of sulfinic acid, yield sulfenyl sulfonate. This labile compound decomposes into free radicals or reacts with another molecule of sulfinic acid producing thiol sulfonate and sulfonic acid. This mechanism explains the variety and unusually high orders encountered in polymerization initiated by sulfinic acid initiators. The proposed kinetic scheme is in agreement with the proton dependence found for both the initiation as well as the disproportionation reactions.
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  • 208
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    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1383-1390 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Using a statistical thermodynamic method we discuss the general shape of a free energy change versus composition curve for a binary copolymerization system. This simple theoretical approach gives reasonable agreement with the experimental results.
    Additional Material: 7 Ill.
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  • 209
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1359-1381 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The low-temperature polymerization of methyl methacrylate initiated with butyllithium-diethylzinc has been studied in toluene and in toluene-tetrahydrofuran and toluene-dioxane mixtures in various proportions. The polymerization process is typically anionic; it is characterized by a very rapid initiation reaction, and the absence of termination and chain transfer reactions, the molecular weight increasing proportionally with the degree of conversion. With toluene as a solvent, the polymer chains are associated, as is shown by viscometric measurements; moreover the polymers produced are highly polydisperse (Mv/Mn = 5.4). The kinetics are very complicated and vary with the range of the catalyst and monomer concentrations. In pure toluene in the presence of the organometallic complex, butyllithium-diethylzinc, the monomer addition is more stereospecific than when butyllithium alone is used as catalyst. By adding tetrahydrofuran to the reaction mixture, the polymer chain association disappears; concomitantly the stereochemical structure of the polymer changes from an isotactic to a mainly syndiotactic configuration. In toluene-tetrahydrofuran mixtures containing from 1 to 10 vol.-% tetrahydrofuran, the kinetics of polymerization can easily be interpreted by assuming the presence of two propagating reactive species which are in equilibrium with each other: the ion pair and the THF-solvated ion pair. The energy of activation of propagation for the free ion pair is equal to 7.5 kcal./mole; for the solvated ion pair a value of 5.5 kcal./mole was found, including the solvation enthalpy of the organometal with tetrahydrofuran. The existence of any relation between the reactivity of the propagating species and the tactic incorporation of the monomeric units has been discussed. The polymerization in mixtures of toluene-dioxane is intermediate between that in pure toluene and that in toluene-HF mixtures; the reaction mechanism however cannot be interpreted with the usual kinetic scheme. The experimental data concerning the rate dependence on catalyst and monomer concentrations are briefly summarized.
    Additional Material: 11 Ill.
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  • 210
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    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1563-1571 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Grafting of maleic anhydride on polyethylene is found to take place also in a homogeneous medium. The course of reaction in nitrogen and in air and the influence of temperature of initiator and polymer concentrations suggest that grafting is due to the chain transfer reaction to polyethylene.
    Additional Material: 5 Ill.
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  • 211
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    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1585-1597 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N-Acryloylglycinamide, N-methacryloylglycinamide, N-acryloyl-DL- and L-alaninamide, and N-methacryloyl-DL- and -L-alaninamide were polymerized by basic catalysts. Polymers with low viscosities were obtained. Automatic amino acid analyses of the hydrolyzates of these polymers indicated that a hydrogen transfer from the terminal amide group took place along with vinyl polymerization. Hydrogen transfer from the secondary amide group was also observed. The ratio of the hydrogen transfer and the vinyl polymerizations was determined by results of automatic amino acid analyses.
    Additional Material: 2 Ill.
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  • 212
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    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1802-1804 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No Abstract
    Additional Material: 1 Tab.
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  • 213
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    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1807-1808 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No Abstract
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  • 214
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1827-1844 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis and cyclocopolymerization with sulfur dioxide of four 1,5- and 1,6-dienes (bicyclopentene, bicyclohexene, dicyclopentenyl ether, and dicyclohexenyl ether) and one tetraene (quartercyclopentene) is described. Under optimum conditions, completely soluble copolymers are obtained from bicyclopentene in high conversions at temperatures down to -39°C. Bicyclohexene also gave soluble copolymers, but in a by far slower reaction and in low conversion. Quartercyclopentene does copolymerize, but as expected, gives only insoluble polymers. The two compounds with 1,6-diallyl ether structure, dicyclopentenyl ether and dicyclohexenyl ether, failed to polymerize. The influence of initiator, temperature, reaction medium, diene concentration, etc., on the properties of the polymers was studied in detail for copolymerizations of bicyclopentene. Only a very limited number of peroxides in unusual large quantities was found to be effective in initiating this copolymerization. The reaction is further limited to a narrow choice of solvents, e.g,. diethyl ether and tetrahydrofuran, in order to obtain soluble products. Polymerization could not be achieved in ethanol, benzene, methylene chloride, dimethyl sulfoxide, and tetramethylene sulfone; excess sulfur dioxide yields only dark and insoluble products. Diene concentrations of below 0.3 wt.-% are normally required to obtain poly(bicyclopentene sulfones) which are soluble in dimethyl sulfoxide, tetramethylene sulfone, or sulfuric acid. Polymerization can be carried out from room temperatures down to -39°C.; optimum results are generally obtained around 0°C. Inherent viscosities of 1.72 (0.5 g./100 ml. dimethyl sulfoxide) have been measured. X-ray diffractions are those of amorphous polymers.
    Additional Material: 7 Tab.
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  • 215
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1881-1887 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of dioxolane initiated by the ∼Si⊕HSO4⊖ ion pair is greatly influenced by water which changes the overall polymerization rate. Particularly great changes are brought about at certain higher conversions (whose values are also a function of an initial concentration of water). The polymerization practically stops at these conversions and the system appears to be close to a monomer - polymer equilibrium. It is shown that the equation Voverall = f([H2O]), which describes the dependence of the overall rate of polymerization on the concentration of water and which was originally derived for the polymerization of trioxane, holds also for the polymerization of dioxolane. The decrease of water concentration during the polymerization was measured and the observed equilibrium was shown to be a kinetic phenomenon.
    Additional Material: 3 Ill.
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  • 216
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1899-1909 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The radiation-induced polymerization of glass-forming systems containing monomers has been investigated. It was found that irradiation below the second-order transition temperature Tg of the systems causes no in-source polymerization but causes a rapid postpolymerization on warming above the Tg after initial irradiation below the Tg. The post-polymerization was followed by differential thermal analysis and ESR spectra. It is caused above the Tg by the release of peroxy radicals trapped below the Tg, and its rate is proportional to the irradiation dose to some extent, often is explosively high, and brings about a remarkably large temperature rise by accumulation of polymerization heat. Irradiation above the Tg causes rapid in-source polymerization which is accelerated by the high viscosity of the monomeric system between Tg and Ts (WLF temperature) compared to crystal or ordinary solution polymerization. The temperature dependence of the in-source polymerization of glassy systems shows a peak between the Tg and Ts which may be the result of competing effects of the rate increase by the decreased termination near Ts and the rate decrease by the decreased propagation caused by the diffusion prevented near the Tg. The degree of polymerization was also investigated. The temperature dependence of the degree of polymerization of the polymers obtained by in-source polymerization shows a peak similar to that of the temperature dependence of conversion. Unusually large values of the Huggins constant k' are noted between Tg and Ts. The degree of polymerization of the polymer obtained by post-polymerized increases with the increase of irradiation dose and the polymerization rate; this may be the result of decreased chain transfer to nonpolymerizable components.
    Additional Material: 5 Ill.
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  • 217
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1951-1965 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Diallyl quaternary ammonium chlorides, bromides and N-alkyldiallylamine hydrochlorides were polymerized with ammonium persulfate (APS) in dimethyl sulfoxide (DMSO). The dependences of yield and molecular weight of polymers on polymerization conditions were examined and quaternary ammonium chlorides were found to have better polymerizability than bromides. The poly(diallyl quaternary ammonium chlorides) obtained with APS - DMSO system are expected to have quite high molecular weights, as determined from the measurement of limiting viscosity numbers of the polymers in NaCl aqueous solution.
    Additional Material: 3 Ill.
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  • 218
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1977-1986 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A study was made of the comparative rates of reaction of active ester functional groups (p-nitrophenyl and 2,4-dinitrophenyl esters) situated on three types of insoluble support polymers and on small, soluble analogs of the polymer molecules. The supports consisted of a styrene - divinylbenzene bead-type polymer (2% DVB), a styrene - divinylbenzene popcorn polymer (0.2% DVB), and a popcorn polymer with 2,3-dimethylbutadiene and substituted styrene units in the chain. p-Nitrophenyl benzoate and 2,4-dinitrophenyl p-isopropylbenzoate were used as soluble analogs. Rates of aminolysis by small molecules (2-aminoethanol and n-tetradecylamine) in pyridine and of solvolysis in alcohols catalyzed by both small (N-methylimidazole) and large (polyvinylimidazole) molecules were determined. With the small amines, finely divided particles of popcorn and bead type styrene polymers reacted at about the same rate, which was approximately 1/5 the rate of reaction of the homogeneous analogs. With a high molecular weight reagent, polyvinylimidazole, the heterogeneous reactions were much slower and the popcorn polymer reacted faster than the bead polymer. In catalyzed solvolyses, the styrene popcorn derivative reacted faster in benzyl alcohol and slower in 1-hexanol than the dimethylbutadiene popcorn polymer derivatives.
    Additional Material: 3 Ill.
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  • 219
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2167-2177 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The stereoregularity of poly(methyl acrylate) and poly(methyl acrylate-αd) was determined from the NMR spectra. A method of quantitative determination of stereoregularity of poly(methyl acrylate) proposed in this paper is based on the fact that in the 100 Mc./sec. NMR spectrum the absorption peaks due to methylene protons in syndiotactic configurations overlap absorptions due to only one of two methylene protons in isotactic configurations. The stereostructure of poly(methy1 acrylates) polymerized with anionic catalysts such as Grignard reagents, n-butyllithium, and LiAlH4 is generally richer in isotactic diads than in syndiotactic diads. For example, poly(methyl acrylate) polymerized with phenylmagnesium bromide as catalyst at -20°C. consists of 99% isotactic and 1% syndiotactic diads. In radical polymerization, the isotacticity of poly(methyl acrylate) is independent of polymerization temperature. Poly(methyl acrylates) polymerized with a Ziegler-Natta catalyst consisting of Al(C2H5)2Cl and VCl4 have configurations similar to those polymerized by radical initiators. The stereoregularity of poly(methyl acrylate-α-d) resembled that of poly(methyl acrylate) polymerized under the same conditions.
    Additional Material: 3 Ill.
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  • 220
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2179-2186 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 2-Methyl-2-butene oxide (2,3-epoxy-2-methylbutane) was polymerized with modified alkylaluminum initiators a t low temperatures to a high-melting, crystalline, film-forming polymer. High yields and comparatively high molecular weights were obtained with Al(i-Bu)3-xH2O initiators in inert diluents. When such initiators were modified with acetylacetone they became ineffective. Ammonia could be substituted for water in formulating an active initiator. Attempts to prepare an active initiator in the presence of the monomer were unsuccessful indicsting competition with the water for Al(i-Bu)3. Thermal decomposition of the polymer produced methyl isopropyl ketone with some pivaldehyde.
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  • 221
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2204-2207 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No. Abstract.
    Additional Material: 1 Ill.
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  • 222
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2259-2268 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: High-resolution nuclear magnetic resonance (NMR) spectra of several kinds of polyesters were measured. Proton signals due to heterolinkages could be observed in some copolyesters, and the average sequence length and the degree of randomness in the copolyester were calculated from the intensities of their signals. A process in the transesterification reaction between two kinds of homopolyester was pursued with the NMR spectra. Random copolyester is formed by the ordinary molten-state copolycondensation and also during the transesterification reaction between two kinds of homopolyester.
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  • 223
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2297-2310 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The dehydrochlorination of chlorinated polystyrene was studied in the temperature range 120-220°C., when HCl was the sole volatile product. The dehydrochlorination was accompanied by the slow development of color and chain scission. The elimination rate fell too rapidly with reaction extent to be accounted for by reduction of reagent. Solution studies in o-dichlorobenzene indicated that the reaction was initially first-order in polymer concentration but was retarded by the polyene reaction products. The overall elimination was interpreted as a radical process in which the product was an active retarder. These observations are also valid for the elimination of HBr from brominated polystyrene.
    Additional Material: 10 Ill.
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  • 224
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2333-2341 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A preferred geometric isomer was found to exist for the Norrish type II photocycloelimination of isobutene from poly(tert-butyl acrylate). A detailed analysis of infrared spectroscopic and kinetic data under thin film conditions is consistent with the mechanism: i.e., a photoinduced rotational equilibrium is established between the cis and trans ester spatial conformations, with isobutene elimination occurring from the cis form. In the glassy state of the polymer, an activation energy of 3.0 kcal./mole was obtained for the elimination step. Energy transfer experiments with naphthalene, benzophenone, and oxygen resulted in a significant decrease in the isobutene yield. This indicates that reaction occurs at least in part from a triplet state of the carbonyl group in the polymer.
    Additional Material: 4 Ill.
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  • 225
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of new aromatic polyethers have been prepared by solution condensation polymerization. The synthesis involves the condensation of a dialkali metal salt of a dihydric phenol with an “activated” or negatively substituted aromatic dihalide in an anhydrous dipolar aprotic solvent at elevated temperatures. The reaction is rapid, free of side reactions, and yields polymers of excellent color. Bakelite polysulfone can be prepared in this manner by reaction of the disodium salt of bisphenol A with 4,4′-dichlorodiphenyl sulfone in dimethyl sulfoxide (DMSO). Only dipolar aprotic solvents are useful for conducting the polymerization. Of these, DMSO and Sulfolane (tetrahydrothiophene 1,1-dioxide) are the most effective. Water or other competing nucleophiles must be absent if high molecular weight is to be obtained. Besides providing the necessary solubility, this highly polar solvent is believed to be essential in providing the rapid polymerization rates observed. The rates are further found to depend on the basicity of the bisphenol salt and upon the electron-withdrawing power of the activating group in the dihalide. As is usual for this type of reaction, the difluorides are found to be more reactive than the corresponding dichlorides. Most of the polyethers are amorphous, rigid, tough thermoplastics with high second-order transitions (Tg). Thermal stability and electrical properties are noteworthy. These and other properties are described for polysulfone, and glass transitions are given for a selected list of the other polyethers.
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  • 226
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2441-2451 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In order to synthesize optically active polymers which have asymmetric carbon atoms in the polymer main chain, polyamides were synthesized at high temperatures by the condensation of the salt prepared from d-tartaric acid with diamines, such as hexamethylenediamine, o-, m-, and p-phenylenediamine. Effects of the solvent, polymerization time, intrinsic viscosity, and pH on the degree of the specific rotation of polyhexamethylene-d-tartaramide, were investigated. From the results of hydrolyses of the polymers, it was found that d-tartaric acid is not racemized during condensation polymerization.
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  • 227
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    Topics: Chemistry and Pharmacology
    Notes: The molecular weight of polysulfone, i.e., the aryl polyether that is prepared by the reaction of the disodium salt of bisphenol A with 4,4′-dichlorodiphenyl sulfone in dimethyl sulfoxide (DMSO) solvent is shown to depend, among other things, on the moisture content of the polymerizing system. In the presence of water, hydrolysis of the sulfone monomer occurs concomitant with the polymerization. This leads to a deviation from the desired 1:1 ratio of coreactant groupings and therefore in attendant reduction in possible molecular weight. The hydrolysis is shown to lead to the formation of the sodium salt of 4-chloro-4′-hydroxydiphenyl sulfone and to a lesser extent polymer derived from self-condensation of this salt. At low levels this salt is essentially inert towards the principal polymerization at hand but in somewhat greater amounts functions as an effective chain terminator. Similar hydrolysis of polysulfone chloro endgroups is believed to occur under the aqueous conditions of polymerization but to a lesser extent than for the sulfone monomer. It is shown that polysulfone or similar polyethers are subject to chain cleavage by bases in DMSO solvent. The base attacks the activated position para to the sulfonyl group with the formation of a chain terminating in a bisphenol A type phenolic group and a chain terminating in a phenolic group of the bisphenol S (p-hydroxyphenyl sulfonyl) type. It is shown that cleavage is probably not important under normal conditions of polymer formation. The effect of these hydrolytic side reactions on the attainment of high molecular weight under conditions of imperfect reaction stoichiometry is shown to be consistent with the above conclusions.
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  • 228
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2458-2459 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 229
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2465-2479 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction between formic acid and disordered cellulose is described. It is shown that a degree of substitution as high as 2.5 can be readily obtained without any catalyst. There is no evidence of any difference between the formylation behavior of this cellulose up to the monoformate level and that beyond this level. Formic acid produces ordered, inaccessible regions in disordered cellulose; this behavior reduces the value of the latter material as a calibration standard in formylation studies and also throws doubt on the basic value of formylation as a method of measuring disorder in cellulose. There is evidence that native celluloses formylate less rapidly per unit amount of hydrogenbond-disordered material than do regenerated celluloses; this may be associated with the fibrillar nature of the native celluloses.
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  • 230
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2563-2578 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Decrystallized cotton cellulose was found to be have gel permeation properties comparable to those of the highly crosslinked dextran and polyacrylamide gels used in chromatography. Partial separations of pairs of sugars, ranging in molecular weight from 120 to 738, were studied by determining the optical rotations of fractions eluted from chromatographic columns, employing a sensitive automatic polarimeter. The elution volumes of individual sugars of known molecular weights provide a quantitative measure of changes produced in the cellulose polymer structure by crosslinking. A significant difference was found between unmodified cellulose and the same material crosslinked by formaldehyde treatment; although crosslinking reduced permeability to larger molecules, the crosslinked material was found to be more permeable than the untreated cellulose to compounds having molecular weights below approximately 1000.
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  • 231
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2617-2627 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The γ-ray-induced polymerization of 1,1,2-trichlorobutadiene, m.p. -48.5°C., was investigated in the temperature range from +55 to -196°C. In the liquid state, the following results were obtained: (1) the rate decreases with decrease of temperature (Ea = 8.0 kcal./mole); (2) the dose rate dependences of rate and of molecular weight are 0.49 and -0.25, respectively; (3) the reaction is inhibited by DPPH; (4) the structure of the polymer is predominantly 1,4 units. It was concluded that the liquid-state polymerization proceeds by a radical mechanism, and the radical yield was found to be 19.7. In the solid state, the following results were obtained: (1) the rate is considerably higher than in the liquid state immediately above the melting point and gradually decreases with decrease of temperature (Ea = 0.34 kcal./mole); (2) the dependence of the rate on dose rate is unity while the molecular weight is independent of the dose rate; (3) the reaction rate is unaffected by DPPH and accelerated by dimethylformamide; (4) the structure of the polymer, 3,4 units, is completely different from that of the polymer obtained in the liquid-state polymerization. The solid-state polymerization is probably of a different nature and is not well elucidated.
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  • 232
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2701-2704 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
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  • 233
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2717-2717 
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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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  • 234
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2629-2636 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Solomon and Ciuta's equation has been deduced from first principles and has been shown to be merely an algebraic consequence of the definition of intrinsic viscosity. Secondly, a consequence of this equation that [η]c should be linear with \documentclass{article}\pagestyle{empty}\begin{document}$\sqrt {2\eta {\rm sp} - 2\ln \eta {\rm rel}}$\end{document} with unit slope, is found to be fairly accurate when examined against literature and our own data, and so this equation is commended not only for single-point determination of [η] but also for representing viscosity variation with concentration up to ηsp 〈 0.60. Thirdly, higher-order approximations are found to be less suitable. Other consequences of Solomon and Ciuta's equation are discussed.
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  • 235
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    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Copolymers of methyl methacrylate with methyl and ethyl α-hydroxymethylacrylate and with α-hydroxymethylstyrene have been prepared with free-radical initiators at temperatures below 80°C. At higher reaction temperatures or under extrusion conditions, alcohol was eliminated and the free hydroxyl content was greatly decreased. All evidence indicates the formation of six-membered lactone groups in this post-polymerization reaction: direct evidence for their formation is lacking, however, since neither infrared nor nuclear magnetic resonance spectra could be used to detect lactonization in this system. The loss of activity from 14C ester-labeled methyl methacrylate copolymer on heating could be correlated with the extent of lactonization. The degree of lactonization is relatively less with copolymers containing higher amounts of hydroxymethyl groups. The resulting polymers exhibit higher heat distortion temperatures and decreased impact resistance when compared to poly(methyl methacrylate). Attempts were made to incorporate similar lactone structures by cyclocopolymerization with methyl methacrylate of α-methacryloxymethylstyrene or ethyl α-methacryloxymethylacrylate, but only crosslinked polymers or polymers with pendent unsaturation were found.
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  • 236
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2939-2941 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
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  • 237
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2946-2948 
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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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  • 238
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2961-2963 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Tab.
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  • 239
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2973-2974 
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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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  • 240
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2997-3007 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In the solution polymerization of tetraoxane catalyzed by BF3·O(C2H5)2, trioxane and methanol-insoluble polymer were produced. However, the amounts of these products depend on the nature of solvent used. A critical concentration of tetraoxane is observed for the formation of methanol-insoluble polymer; at less than this critical concentration of tetraoxane no methanol-insoluble polymer is obtained, but trioxane is preferentially produced. This critical concentration of tetraoxane is higher in a more polar solvent, so the amount of methanol-insoluble polymer produced decreases and the amount of trioxane produced increases with increasing the polarity of solvent used. These results may be explained in terms of a stabilization of the active center leading to formation of trioxane by a solvation with solvent.
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  • 241
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2815-2823 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The influence of SeOCl2 on the polymerization of propylene by TiCl3-Al(C2H5)3, and the temperature dependence of the stereospecificity of the catalyst, TiCl3-Al(C2H5)3, have been investigated. SeOCl2 decreases the rate of polymerization and increase the stereospecificity of the catalyst, which could be explained on the basis of a decrease of the concentration of Al(C2H5)3 accompanied by a reaction between Al(C2H5)3 and SeOCl2. On the other hand, the stereospecificity of the catalyst, TiCl3-Al(C2H5)3, increases gradually with a decrease in polymerization temperature from 40 to 0°C. From these results, we conclude that SeOCl2 exerts no essential influence on the polymerization of propylene by TiCl3-Al(C2H5)3, and that the stereospecificity of the catalyst is attributed mainly to the reducing ability of the organometallic compound.
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  • 242
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2857-2865 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Quantitative determination of endgroups in an acrylonitrile-methyl acrylate (90:10) copolymer polymerized with NaClO3-Na2SO3 redox system in aqueous solution was carried out by conductometric and dyeing methods for SO3H incorporated into polymer, x-ray analysis for S in polymer, and polarography for Cl in polymer. The number-average molecular weight was measured by osmometry. Determination of endgroups was done on both unfractionated polymer and fractionated polymer. On the average, 0.95 mole S and 0.71 mole SO3H per molecule were found in unfractionated polymer. For fractionated polymer, 0.68 mole S and 0.69 mole SO3H per molecule were found. A small amount of Cl was also found in both unfractionated polymer and fractionated polymer. The difference between results for the two polymers and polymerization kinetics are discussed.
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  • 243
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2891-2898 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymers [N(PN)4(C6H5)6N=P(C6H5)2(CH2)4P(C6H5)2]x and [N(PN)4(C6H5)6N=P-(C6H5)2C6H4C6H4P(C6H5)2]x have been formed by thermal copolymerization of trans-2,6-diazidohexaphenylcyclophosphonitrile [N3(PN)4(C6H5)6N3] with either 1,4-bis-(diphenylphosphino)butane [(C6H5)2P(CH2)4P(C6H5)2] or 4,4′-bis(diphenylphosphino)-biphenyl [(C6H5)2C6H4C6H4P(C6H5)2]. The maximum molecular weights obtained were about 10,000. A polymer endcapped with triphenyl phosphine was stable to 400°C.
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  • 244
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2927-2937 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(phosphine oxides) and poly(phosphine sulfides) of ferrocene were synthesized in the melt phase. The resulting ferrocene polymers, linked by phosphorus bridges, were thermally stable and infusible solids, of low molecular weight (M̄n 〈 4000). Phenyldichlorophosphine, phenyldichlorophosphonate, and phenylphosphonothioic dichloride were copolymerized with ferrocene in the melt phase (80-110°C.) with ZnCl2 as a catalyst. As the polymerization temperature was raised, cleavage of cyclopentadiene rings from iron became more pronounced, and cyclopentane-bridged polymers of ferrocene were produced in competition with the ferrocene-phosphorus polymers. The cleavage-polymerization process became predominant at 140°C. The structures of poly(phosphine oxides) (and sulfides) of ferrocene were verified by infrared and nuclear magnetic resonance spectroscopy.
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  • 245
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2964-2966 
    ISSN: 0449-296X
    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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  • 246
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 3139-3150 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Dialkylzinc-Lewis base systems are found to be active catalysts for the polymerization of alkylene oxides. The diethylzinc-dimethyl sulfoxide system is especially effective in the preparation of high polymers of ethylene oxide and propylene oxide. Diethylzine does not react with dimethyl sulfoxide, but there is strong association between the compounds. The proton magnetic resonance spectrum of a poly(ethylene oxide) prepared by the catalyst system suggests that the n-butoxyl group is attached to the end of the polymer chain. Polymerization of ethylene oxide seems to be initiated by the ethyl-zinc bond. The active species of the system seems to be diethylzinc coordinated with dimethyl sulfoxide. The efficiency of the catalyst system for the formation of high molecular weight polymer is 10-1-10-2. The other part of the catalyst is responsible for the formation of low polymers.
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  • 247
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 3207-3211 
    ISSN: 0449-296X
    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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  • 248
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    Topics: Chemistry and Pharmacology
    Notes: The initiation process for the polymerization of tetrahydrofuran with (C6H5)3C+SbCl6- has been studied. Two mechanisms have been considered: a cation-addition process, and a process in which tetrahydrofuran donates a hydride ion to the cation of the initiator to form triphenylmethane. The biscarbonium salt [(C6H5)2C+C6H4CH2]2(SbCl6-)2 has been synthesized and used to initiate the polymerization of tetrahydrofuran. The results are consistent with the hydride-ion mechanism but may be inconclusive because of chain transfer. NMR experiments with 0.05-0.2M solutions of initiator in tetrahydrofuran show that triphenylmethane is rapidly produced in an amount equal to the molar amount of initiator originally present. Some NMR evidence for the presence of an acetal end group in the polymer has been obtained. It is concluded that the initiation process in this system definitely involves the formation of triphenylmethane, although a detailed, unique mechanism cannot be selected at this time.
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  • 249
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 241-241 
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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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  • 250
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 251-256 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Terpolymerizations of ethylene, propylene, and dicyclopentadiene were carried out in which the dicyclopentadiene was added to the reaction system in two equal portions at the beginning and midpoint of each run, while the monoolefins were added continuously. In the resultant elastomers, unsaturation remains much more constant throughout the course of the polymerization than for terpolymers obtained when all dicyclopentadiene is added at the start of the reaction. Yield and molecular weight of the terpolymers produced by either technique are quite comparable, however. With VCl4 catalyst (with Al2Et3Cl3 cocatalyst) in heptane solvent, the two-step addition of the diene gave terpolymers with little gel, in contrast to the high gel in terpolymers formed with the single initial addition of the diene. This system also produced terpolymer with the highest final unsaturation and molecular weight. Catalysts of VCl4, VOCl3, or V(C5H7O2)3 in benzene gave terpolymers of moderate unsaturations and molecular weights.
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  • 251
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    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The ring-opening polymerizations of cyclic sulfides containing three-, four-, and fivemembered rings were studied. In conjunction with these polymerizations, the relative basicities of the cyclic sulfides employed were also investigated. Polymerizations were effected by the use of phosphorus pentafluoride, boron trifluoride ethyl ether, triethylaluminum, and trimethyloxonium tetrafluoroborate. The resulting polymers were oxidized to the sulfones and differential thermal analyses were obtained on the sulfide polymers as well as the sulfone analogs.
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  • 252
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 339-353 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of styrene was carried out in a cyclohexane solution of natural rubber with stannic chloride. It was found that the grafting copolymerizations of styrene took place as well as the cyclization of rubber. The rate of polymerization of styrene was proportional to the second power of the concentration of styrene and to the concentrations of stannic chloride and natural rubber, respectively. The overall activation energy was about 6 kcal./mole. The percentage grafting increased with increasing concentration of rubber. On the other hand, the grafting efficiency showed the reverse tendency. The percentage grafting could be increased to 150% by the addition of nitrobenzene, a polar solvent.
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  • 253
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 395-396 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Tab.
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  • 254
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 553-561 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Aromatic polysulfonamides have been prepared by solution polycondensation of aromatic disulfonyl chlorides and aromatic diamines with a suitable acid acceptor in such solvents as N,N-dimethylacetamide and tetramethylenesulfone. The highest molecular weight polymers were obtained by using 2,6-dimethylpyridine as the acid acceptor in tetramethylenesulfone as the solvent. Clear, translucent, brittle films of the polysulfonamides may be formed from solution or from melt.
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 537-543 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of three true polyampholytes with unequivocally alternating acidic and basic groups attached directly to the skeletal backbone of the polymer chain have been prepared. This was accomplished by copolymerizing 3,6-diallyl-2-piperidone with the α,ω-dithiols containing 2-, 4-, and 6-methylene groups. The polymerization was carried out in an emulsion system initiated by 2,2′-azobisisobutyronitrile (AIBN), yielding soluble piperidone-containing polymers with molecular weights in the 20,000-30,000 range. The piperidone rings in the polymers were hydrolyzed by dilute sulfuric acid to yield the desired polyampholytes. Fibers were prepared by wet-spinning formic acid solutions of the polyampholyte into saturated salt solution or by melt-spinning. These fibers were quite elastic. We were unsuccessful in demonstrating that mechanical energy could be attained by the effect of pH on the fibers. Similarly, no pH effect could be elicited in Instron tests. The stress-relaxation curve showed a marked positive force-temperature effect characteristic of rubberlike materials with few crosslinks. In a check of transition temperatures, it was noted that on repeated runs the second-order transition temperature rose markedly, suggesting an irreversible change. Viscometric studies clearly demonstrated polyelectrolyte behavior. X-ray diffraction studies of the polyampholytes showed that maximum crystallinity and orientation occurred in the polymer containing as part of the repeating unit the 1,4-butane dithiol moiety.
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  • 256
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 593-603 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Methacrylonitrile (MAN) was polymerized with diethylmagnesium. Acetone-insoluble portions of the polymers are found to be crystalline. Highly crystalline portions can be isolated by further extraction of the acetone-insoluble parts with dimethylformamide (DMF). A film of DMF-insoluble fraction can be oriented uniaxially by hot-press rolling. The crystalline PMAN is insoluble in the usual solvents for amorphous PMAN because of their crystallinity and is easily soluble in CF3COOH or Cl2CHCOOH. The viscosity-molecular weight relationship was determined in Cl2CHCOOH at 30°C. as [η] = 3.24 × 10-3M0.520. We found several crystalline bands in the infrared spectra, for example, at 1192 and 885 cm.-1. Formation of the carbonyl group in the polymer is discussed, and it is concluded that it may be formed by the hydrolysis of conjugated cyclic imine or hydrolysis of the nitrile group in the polymer to acid amide.
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  • 257
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 665-673 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The rate of polymerization with the VOCl3-AlEt2Br catalyst system at 30°C. in n-hexane reached a maximum at an Al/V molar ratio of 1.5. At this ratio, the rate of polymerization was first-order with respect to catalyst and second-order with respect to monomer concentrations. The apparent activation energy calculated was 6.4 kcal./mole. Diethylzine was found to act as a chain transfer agent. However, the molecular weights of polymers obtained were low. The possibility of bromide-containing catalyst sites acting in the termination reaction has been investigated. The average valence of vanadium is discussed in relation to molecular weights.
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  • 258
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 681-682 
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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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  • 259
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 687-687 
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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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  • 260
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1021-1032 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Fluorescent conjugates of polyethyleneimine (PEI) were prepared by conjugation of fluorescent dyes, fluorescein isocyanate (FIC), and 1-dimethylaminonaphthalene-5-sulfonyl chloride (DNS), to PEI. The degree of polarization of the fluorescence was measured as a function of temperature and solvent viscosity on aqueous solutions of the conjugates and the data thus obtained were analyzed in terms of an equation of the Perrin type to calculate the mean relaxation time of the conjugate. The mean relaxation times obtained for the two types of the conjugates, which differ in the excited lifetime by a factor of about three, practically agree with one another and are about 2.5 X 10-8 sec. The relaxation time of the DNS conjugate increases with increasing molecular weight of the conjugate from 2 X 10-8 to 4 X 10-8 sec. These values are much larger than those of the PAA conjugates reported in Part I of this series. The relaxation time of this order may correspond to that for the cooperative rotary motion of about ten monomeric residues on the PEI chain, that is, for the motion of an intermediate segment of the PEI molecule in solution. Finally, relaxation time-molecular weight relationships for various types of fluorescent conjugates are compared. It is suggested that these data may serve as a basis for elucidating the mode of motion of a given molecule in solution from the polarization data.
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  • 261
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1113-1118 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Four new polybenzimidazoles with aryl sulfone linkages between the recurring units have been prepared in order to study their thermal stability and solubility properties. The polymers prepared were high molecular weight materials with good thermal stability.
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  • 262
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1137-1164 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In polymerization of vinyl chloride monomer, free radicals precipitate on or within aggregates of partially swollen dead polymer. Polymerization on the solid polymer is characterized by autoaccelerating rates due to a progressive reduction in termination rate. This reduction in termination rate is due to the fact that as the reaction progresses and more polymer accumulates there is a decrease in probability that chain transfer of polymer radicals to monomer will generate a mobile radical, which can readily terminate an occluded or stuck free radical. From the appearance of the particles of solid polymer in the system, it has been concluded that free radicals precipitate both on polymer particle surface and inside the open structure of polymer particles.
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  • 263
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1191-1201 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: For the polymerization of n-octadecene-1 with catalysts derived from titanium tetrachloride and triethylaluminum, it has been shown that, in addition to polymerization of the olefin, the formation of isomerized olefin occurs. The latter is predominantly trans-n-octadecene-2 and its formation is favored by increase in Al:Ti mole ratio, in catalyst concentration, and in reaction temperature. It has also been shown that 1,1-disubstituted ethylene is present in the nonpolymeric reaction products. The influence of added trans-n-octadecene-2 or trans-n-octadecene-7 on the polymerization of n-octadecene-1 has been studied, and it is shown that the 2-isomer has the more pronounced effect on polymer yield and intrinsic viscosity. It has also been shown that no significant copolymerization of terminal with nonterminal octenes or octadecenes occurs under these conditions. Results indicate that, in polymerizations of this kind, the interaction of catalyst with isomerized monomer is probably an important factor in determining polymer yield and molecular weight. The isomerization reaction is also of interest as a general preparative method for trans-2-olefins.
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  • 264
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1289-1296 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: From the conversion-composition data of Gruber and Elias, the reactivity ratios of styrene (M1) and methyl methacrylate (M2) were calculated to be r1 = 0.55 ± 0.02 and r2 = 0.58 ± 0.06 at 90°C. The least-squares method was then used on these and literature values at other temperatures to obtain the Arrhenius expressions: In r1 = 0.04736 - (235.45/T), and ln r2 = 0.1183 - (285.36/T). Using literature values for the homopolymerization steps, A11 = 2.2 × 107l./mole-sec., E11 = 7.8 kcal./mole, and A22 = 0.51 × 107 l./mole-sec.-1, E22 = 6.3 kcal./mole, activation energies and frequency factors were then calculated for the cross-polymerization steps: A12 = 2.1 × 107 l./mole-sec., E12 = 7.3 kcal./mole, and A21 = 0.45 × 107 l./mole-sec., E21 = 5.7 kcal./mole.
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  • 265
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1297-1305 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The retardation of acrylonitrile (AN) polymerization by p-toluenesulfinic acid (TSA) in the presence of relatively strong acids has been further investigated. Conductance measurements supported the hypothesis that an ionic complex, presumably RSO2H2+, is obtained by a reaction of the sulfinic acid with a proton. It is postulated that this complex is a chain transfer agent for the observed retardation. On the basis of this assumption, a kinetic scheme was developed involving additional termination steps by the complex. The scheme accounts for the maximum in initial rate observed on increasing the concentration of added sulfonic acid at a constant TSA concentration. It also provides an explanation for the elimination of the autoacceleration in the bulk polymerization of AN when strong acids are added. The orders derived from the kinetic equations are in good agreement with the orders evaluated from the kinetic experiments.
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  • 266
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1313-1326 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Acrylonitrile grafts readily to granular corn starch in aqueous slurry when initiated by hydrogen peroxide plus activator. Prime evidence for grafting lies in the ease of separating PAN from starch in high yield when the initiator is azobisisobutyronitrile rather than peroxide. Grafting efficiencies are determined by extraction with appropriate solvents: dimethylformamide for homo-PAN, and boiling water for ungrafted starch. Grafting efficiencies of PAN range from 78 to 95%, M̄n values for grafted PAN are 4,000 to 90,000, and frequency of attachment of side chains range from 300 to 1100 glucose units per chain. Increasing the monomer level, at fixed initiator concentration, tends to result in longer rather than more frequent side chains. AN behaves much as has been previously found for MMA, but the somewhat more efficient grafting at more frequent intervals and the more nearly uniform distribution of polymer in the starch granule suggest that AN penetrates the starch granule more readily than MMA.
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  • 267
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1391-1394 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Column systems for gel permeation chromatography are usually calibrated by eluting a series of sharp polymer fractions of known molecular weights and by correlating their elution volumes with molecular size or weight. A different method for calibration is proposed in which only one polymer sample, with a broad, well-characterized molecular weight distribution, is used. The cumulative distribution and the integrated, normalized GPC chromatogram are successively superimposed, and molecular weights and corresponding elution volumes are correlated. It is found that calibration curves obtained in this manner show a definite curvature. A possible explanation and correction for this behavior is given, based on the concentration dependence of elution volumes.
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  • 268
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1415-1423 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Radiation-induced bulk polymerization of maleimide in both solid and liquid states was studied. Benzoquinone inhibited the liquid-state polymerization and retarded solid-state polymerization. The results of ESR study showed that solid monomer irradiated at 61°C. gave a spectrum, the concentration of which slowly decreased without changing the shape at 61°C. The radical detected at 61°C. was shown not to be the main propagating species. Overall rate polymerizations in the liquid and solid states were expressed, respectively, by first-order and zero-order rate equations with respect to the concentration of monomer. The overall rate constants in liquid and solid states were proportional to I0.9 and I1.0, respectively.
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  • 269
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1433-1442 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The network parameters of swollen, solution-crosslinked polymer filaments can be collected from deswelling measurements in solutions of nonpermeating polymer or, as shown in this paper, from the stress-strain relation when in equilibrium with the surrounding solvent. The degree of swelling, at which the partial molar free energy of elasticity equals zero, is found to vary with solvent power in agreement with earlier findings on other systems. Comparison with results of studies on rubber networks crosslinked in the absence of diluent show that previously observed discrepancies between theory and experiment can be attributed to the deficiency of the single term involving the one-third power of the volume fraction of polymer in the swollen network to describe the contribution of the partial elastic free energy.
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  • 270
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1486-1488 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Isobutylene has been copolymerized with 2,5-dimethyl-2,4-hexadiene using a boron trifluoride catalyst in petroleum ether solution. Ozonization of the products followed by reduction with lithium aluminum hydride has furnished polyisobutylene glycols in good yield.
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  • 271
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1513-1526 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The oxidative and thermal degradation of some polyaromatic heterocyclics in air and helium has been studied by dynamic thermogravimetry to 1400°C. Decomposition characteristics are the result of polymer structure, molecular weight, and method of preparation. Decomposition in air follows first-order rate laws, while degradation under inert conditions does not appear to follow simple rate laws. The activation energies for the decomposition in air are between 30 and 35 kcal./mole for most polymers investigated. Carbonaceous polymer residues at 1400°C. are present in varying quantities.
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  • 272
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1425-1432 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In a previous paper, the radiochemical determination of low unsaturation in polyisobutene was effected by reacting radiochlorine with the double bonds. The reaction is one of substitution rather than addition, and the derivation of true unsaturation values required an assumption to be made regarding the number of chlorine atoms (one or two) incorporated per double bond. In this paper the assumption is tested by examining the stoichiometry of the chlorination of suitable model compounds of known or measurable unsaturation under the experimental conditions used previously. It is found that reaction leads to a monochloro product rather than the dichloro product previously assumed. Conclusions regarding the chain termination process in isobutene polymerization are re-examined in the light of this result.
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  • 273
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1481-1485 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Tab.
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  • 274
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1453-1466 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Four phenyl-substituted polyquinoxalines have been prepared by the reaction of combinations of two tetraamines, 3,3′-diaminobenzidine and 3,3,′4,4′-tetraaminodiphenyl ether, with two bisbenzils, 4,4′-dibenzil and 4,4′-oxydibenzil. The polymers were prepared by melt and solution polymerizations. Melt condensations were performed at 180, 220, and 280°C. and samples were periodically removed and characterized. The solution polymerizations consisted of two stages, initially forming an intermediate molecular weight polymer (ηinh 0.6-1.0) which was advanced at 400°C. to final polymer (ηinh 1.5 to 2.2). Clear yellow films, cast from m-cresol solution, exhibited good toughness and flexibility. The phenyl-substituted polyquinoxalines exhibited excellent oxidative and thermal stability. Polymer decomposition temperatures in air were generally about 550°C. Isothermal aging at 371°C. (700°F.) in air showed weight retentions as high as 93 and 50% after 100 and 200 hr., respectively. Weight-average molecular weight determination by light-scattering technique on a polymer with an ηinh of 2.16 suggested a value of 247,000. Certain physical properties of the phenyl-substituted polyquinoxalines are compared with those of the corresponding ordinary polyquinoxalines to illustrate the advantageous effect of introducing a phenyl group on the quinoxaline ring.
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  • 275
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1501-1511 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Several homopolymers and copolymers of the title compounds have been prepared by radical initiation with potassium persulfate or diethyl azobisisobutyrate. The copolymers exhibit a combination of the properties of the homopolymers of the monomers. The homopolymers are adhesive, very slightly elastic, and show cold flow. Several of the copolymers show possible promise for use as adhesives.
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  • 276
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1527-1538 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Furan, pyrrole, and thiophene were polymerized under catalysis by trichloro- and trifluoroacetic acid to produce colored polymers which were characterized by various methods, including electronic and proton magnetic resonance spectra and electrical conductances of deeply colored trichloroacetic acid adducts. The predominant repeat units of these polymers are of the same type as those of deeply colored cyclopentadiene polymers, except that a CH2 group is replaced by O, NH, or S.
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  • 277
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1547-1562 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyethylene has been grafted with maleic anhydride, as proved by the infrared spectra and the properties of the grafted films. The influence of oxygen and a comparison of the effectiveness of benzoyl peroxide and AIBN showed that polyethylene macroradicals are formed through the decomposition of hydroperoxide and peroxide groups. Side chains of poly(maleic anhydride) are formed by a combination of polyethylene macroradicals with those of poly(maleic anhydride). This mechanism of reaction was confirmed by the influence of the amount of film, the initiator and monomer concentrations, and temperature on the percentage of grafting.
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  • 278
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1599-1607 
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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 polymerization of N-[1-(1-substituted-2-oxopropyl)]acrylamides and -methacrylamides are described. Seven new monomers were prepared by two kinds of synthetic procedure. The polymerization of these monomers was carried out. Monomer reactivity ratios in the polymerization of these monomers with styrene were determined and the Alfrey-Price Q and e values calculated. The effects of substituents on the reactivities in copolymerization were observed, and an interpretation of the results is given.
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  • 279
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1635-1643 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Nuclear magnetic resonance, infrared, and ultraviolet spectroscopy were used to elucidate the structure of oxidized polystyrene. To identify the nuclear magnetic resonance peaks of the degraded polystyrene, deuterated polystyrenes were synthesized and degraded. The primary structure present in the degraded polystyrene was found to be an aromatic carbonyl group. It was shown that this structure was formed regardless of the presence of ultraviolet light and was also present when polystyrene was degraded in carbon tetrachloride solution. When polystyrene was degraded in carbon tetrachloride solution, stable polymeric peroxides were formed in a concentration of 4 peroxide groups for every 1000 styrene units.
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  • 280
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1671-1681 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Turbidimetric titrations have been made on polystyrene and poly-o-chlorostyrene in a series of solvents to deduce the solubility parameters of polymers from the Flory-Huggins interaction parameter χ. The assigned solubility parameter for polystyrene agrees well with the reported values obtained from swelling measurements. Brief discussion of the exceptional behavior in the solvent powers of paraffins is given.
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  • 281
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1699-1704 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 9-Vinyl anthracene has been polymerized by three methods in cationic systems to obtain organic photoconductors. Cationic polymerization catalysts used were titanium tetrachloride and aluminum chloride anhydride. According to the degree of conversion from poly(9-vinyl anthracene) to poly(9,10-dimethylene anthracene) the photosensitivity increased.
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  • 282
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1717-1726 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The dielectric properties of vinylidene chloride - vinyl chloride copolymers prepared at conversions of less than 5% were studied. The magnitude of dielectric α absorption (absorption at high temperature) is not a linear function of the composition on account of the effect of the copolymer's crystallinity. On the other hand, a nearly linear relationship was observed between the dielectric glass transition temperature (Tg) of low-conversion polymer and its composition, while the relationship in a high-conversion copolymer system, observed by Boyer and Narita et al., is sigmoid. The differences in the temperature - composition relationship between low-conversion and high-conversion copolymer systems are illustrated in terms of the distribution of molecular composition. The dielectric β absorption observed in the copolymer whose vinyl chloride molar fraction is more than 0.5 was interpreted as the local motion of vinyl chloride sequences, and the vinyl chloride sequence of 2 or 3 units is sufficient to participate in the β absorption of the copolymer.
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1753-1763 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In the terpolymerization of 2-chloroethyl vinyl ether - maleic anhydride - acrylonitrile and p-dioxene - maleic anhydride - acrylonitrile systems the compositions of the terpolymers obtained from feed of the same mole fraction were found to be changed beyond the limit of error for the given amounts and kinds of solvent. This change was considered to be divided into two parts. The first part, discussed quantitatively, was due to a dilution effect on the equilibrium complex formation between donor and acceptor monomer, and the second, as tentatively proposed, was due to a solvent effect on the reactivity of the complex.
    Additional Material: 4 Ill.
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  • 284
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1797-1801 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No Abstract
    Additional Material: 2 Ill.
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  • 285
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1807-1807 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No Abstract
    Type of Medium: Electronic Resource
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  • 286
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1845-1853 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cyclocopolymerization of maleic anhydride and four 1,5- and 1,6-dienes (bicyclopentene, bicyclohexene, dicyclopentenyl ether, and dicyclohexenyl ether) and one tetraene (quartercyclopentene) is described. Soluble, low molecular weight copolymers were obtained from all five compounds. Their compositions approach 2:1 copolymer ratios. Fused ring structures are proposed as the main repeating units. Among the compounds listed, bicyclopentene copolymerized most easily and gave good conversions for monomer ratios of 2:1. Quartercyclopentene and dicyclopentyl ether, the other five-membered ring compounds, also polymerized to good-to-fair yields. However, a monomer ratio of about 4:1 was required to obtain conversions comparable to a 2:1 maleic anhydride - bicyclopentene polymerization. The six-membered systems, bicyclopentene and dicyclopentenyl ether, gave consistently low conversions, even with a 4:1 monomer ratio. The influence of the initiator system, initiator concentration, and reaction medium was studied on copolymerizations of bicyclopentene. Best results were obtained in acetic anhydride with azobisisobutyronitrile as the initiator.
    Additional Material: 5 Tab.
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  • 287
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1865-1880 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyurethans with chloromethyl side chains were prepared by the polyaddition reaction of bischlorohydrins and diisocyanates. The polyurethans had inherent viscosities in a range of 0.22-0.60 and gave transparent films by solution casting. These polyurethans were easily converted to the polyoxazolidones by treatment with sodium methoxide. The polyoxazolidones had inherent viscosities up to 0.51, and gave transparent films by solution casting.
    Additional Material: 3 Ill.
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  • 288
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1911-1925 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of N-vinylcarbazole (VCZ) in ethylene dichloride, acetone, benzene, and dioxane with cupric nitrate, ferric nitrate, and ceric ammonium nitrate as catalyst was studied. In all cases the polymerization seemed to be of a cationic nature, judged by copolymerization with styrene. Electron spin resonance (ESR) spectroscopy was made for the polymerization system and also for a system containing N-ethylcarbazole instead of VCZ. Singlet ESR spectra were observed for all systems containing ceric salt and for some systems containing ferric salt but not for systems containing cupric salt. The ESR spectra indicated the formation of an ion radical by electron transfer between the oxidizing metal salt and the carbazole derivatives. Mechanisms of initiation other than electron transfer were less likely, and it was concluded that the initiation process was most likely to be of the electron transfer type.
    Additional Material: 8 Ill.
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  • 289
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1937-1949 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The copolymerization of tetraoxane with styrene catalyzed by BF3·O(C2H5)2 was studied at 30°C. to determine whether a cyclic monomer can copolymerize with a vinyl monomer. The formation of the copolymer was confirmed by elementary analysis of both benzene-soluble and benzene-insoluble fractions of the polymer obtained. It was found by gas chromatography that a fairly large amount of 4-phenyl-1,3-dioxane and a small amount of trioxane were formed in the present system, in addition to polymers. Roughly a third of the total amount of the monomers reacted was consumed in the formation of methanol-insoluble polymer, a third for 4-phenyl-1,3-dioxane, and another third for trioxane and unknown products which could not be indentified. The formation of these cyclic compounds during the copolymerization may be explained in terms of a back-biting (or intramolecular transacetalization) reaction. The cationic reactivity of tetraoxane was found to be similar to that of styrene on the basis of both the consumption rate of each monomer in the copolymerizing system and the composition of the methanol-insoluble polymer obtained.
    Additional Material: 11 Ill.
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  • 290
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 1967-1975 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The copolymerization of acrylonitrile (AN) with methyl acrylate (MEA) has been investigated in three types of polymerization, i.e., emulsion polymerization in water with a water-soluble initiator, suspension polymerization in water with an oil-soluble and water-insoluble initiator, and solution polymerization in dimethyl sulfoxide (DMSO). Monomer reactivity ratios at 50°C. for AN and MEA are found to be r1 = 0.78 ± 0.02, r2 = 1.04 ± 0.02 in emulsion polymerization; r1 = 1.02 ± 0.02, r2 = 0.70 ± 0.02 in DMSO solution polymerization; r1 = 0.75 ± 0.05, r2 = 1.54 ± 0.05 in suspension polymerization. The large differences found in the reactivity ratios may be attributed to the different ratio of concentration of two monomers in the loci of polymerization. Chemically, AN is somewhat more reactive than MEA as shown by the reactivity ratios in DMSO. In the case of the suspension polymerization, the MEA/AN ratio in the polymer particles in which polymerization occurs may be higher than that in the total phase. Experimental results of the emulsion polymerization show that the emulsion polymerization of AN occurs both in the particles and in water. In addition, rates of the copolymerization of AN with MEA have also been investigated.
    Additional Material: 5 Ill.
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  • 291
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2005-2012 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Kinetic studies on the polymerization of ethyl acrylate have been carried out and the various rate constants and their corresponding activation energies determined.
    Additional Material: 3 Ill.
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  • 292
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cationic copolymerization of tetrahydrofuran and propylene oxide was studied in a batch system. Boron fluoride ethyl ether and 1,2-propanediol were used as catalyst - co - catalyst system. Number-average molecular weights M̄n of various copolymers were determined by vapor-pressure osmometry (VPO) and hydroxyl endgroup analysis (OH). The VPO and OH molecular weights differed considerably. To explain the differences, several copolymers were analyzed by gel permeation chromatography (GPC). The chromatograms obtained showed for each copolymer analyzed two peaks, one located in the high molecular weight region, the other in the low molecular weight region. An attempt is made to correlate the results and to show the usefulness of GPC in the characterization of THF - PO copolymers.
    Additional Material: 5 Ill.
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  • 293
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2013-2021 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: From the temperature dependence of infrared spectra of poly(vinyl chloride) samples prepared by different methods, the intensity of the band at 690 cm.1 (proportional to the number of isotactic diads in the sample), as well as that of the tacticity-independent C—H stretching band, was found to be independent of the crystallinity of the sample. These lines were therefore applied for the tacticity determination in poly(vinyl chloride), measured in the form of KBr pellets. The numerical tacticity value was obtained from the known values of absorbance coefficients of SCH and SHH type C—Cl stretching bands in solution, and from the shape of the spectrum.
    Additional Material: 6 Ill.
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  • 294
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The radical-initiated copolymerization of carbon monoxide and ethylenimine in the presence of ethylene was studied quantitatively. Carbon monoxide copolymerized with difficulty with ethylenimine with α,α′-azobisisobutyronitrile as radical initiator. In the presence of a small amount of ethylene, however, a remarkable amount of crystalline powdery poly-β-alanine (nylon 3) was obtained. The crystalline copolymer, which mainly consists of nylon 3 and contains a small amount of nylon 5 and other substances of higher homologous nylon structure, was obtained in the presence of a large amount of ethylene. This copolymer scarcely contained any ketone structure. Increasing the total feed of the equimolar mixture of the monomers increased the conversion of total monomer and nylon 3 content in the copolymer formed. The effect of increasing carbon monoxide content in this system was to increase both the conversion and the nylon 3 content in the copolymer. In both cases the copolymers were almost identical with nylon 3. Increased ethylene content in the monomer feed, however, increased the conversion and the content of higher homologous nylon structures, such as nylon 5 and 7. From the results it was concluded that ethylene was involved not only in the propagation reaction but also particularly in the initiation reaction.
    Additional Material: 10 Ill.
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  • 295
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2055-2065 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Styrene oxide has been polymerized by the triisobutylaluminum-water catalyst system. Kinetic studies of the effects of varying the monomer, triisobutylaluminum, and water concentrations in benzene solutions have been made. Styrene oxide was consumed in two reactions: an initial fast one producing trimer and a slower reaction forming higher molecular weight polymer.
    Additional Material: 4 Ill.
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  • 296
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polysiloxanes containing carboranylbutyl and methyl pendant groups were investigated, to determine their resistance to thermal decomposition when heated in air. Results indicate that the copolymers degrade through Si—C as well as Si—O bond rupture. At 300°C. thermooxidative scission of pendant groups was the predominant reaction. whereas Si—O and Si—C bond rupture occurred at 500°C. Variations in the behavior of the copolymers studied suggest that the carborane nucleus provides some inhibiting influence on their thermal decomposition. This is mainly attributed to steric hindrance effects rather than polarity factors. Chain extension with tin octoate caused a reduction of thermal stability, probably because of the addition of Sn—O bonds to the molecules.
    Additional Material: 10 Ill.
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  • 297
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2192-2198 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No. Abstract.
    Additional Material: 2 Ill.
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  • 298
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2202-2203 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No. Abstract.
    Type of Medium: Electronic Resource
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  • 299
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2783-2789 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The copolymerization of isoprene with styrene initiated with sec-butyllithium in cyclohexane solution has been studied by kinetic methods. The rates of the homopolymerization have been measured by normal methods. The rates of the cross-propagation reactions were measured by the rate of appearance or disappearance of the ultraviolet absorption of polystyryllithium when the individual chain ends were reacted with the opposite monomer in the absence of the first. The rates of some of the reactions were also measured in the presence of the other monomer. It was found that polyisoprenyllithium reacted with both monomers with a one quarter-order dependence, and the polystyryllithium with a one half-order dependence. It was found possible to describe the copolymerization in terms of the four individual rate constants and to predict the initial copolymer composition. It was not found necessary to resort to explanations based on preferential absorption of isoprene around the chain ends to explain the high isoprene content of the copolymer.
    Additional Material: 2 Ill.
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  • 300
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    Journal of Polymer Science Part A-1: Polymer Chemistry 5 (1967), S. 2835-2841 
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The pore-size distributions of various grades of porous glass were determined by gas desorption and mercury porosimeter measurements. This allowed the calculation of elution volumes as a function of pore diameters. The coil sizes of polystyrenes in toluene were obtained for a series of molecular weights from hydrodynamic theory and matched with pore diameters. In this manner, expected calibration curves for gel permeation chromatography could be calculated. Good agreement was found with experimental data.
    Additional Material: 5 Ill.
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