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  • ASTROPHYSICS  (1,124)
  • Physics  (1,055)
  • 1980-1984  (2,179)
  • 1925-1929
  • 1920-1924
  • 1983  (1,116)
  • 1982  (1,063)
  • 1928
Collection
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  • 1980-1984  (2,179)
  • 1925-1929
  • 1920-1924
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  • 1
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 137-145 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New diamines containing amide and oxyethylene linkages were prepared by reduction of the corresponding dinitro compounds which were obtained by the reaction of p-nitrophenol with arylenebis(2-oxazolines) in dimethylformamide at 130°C. Moderate- to high-molecular-weight polyamides and polyamide-imides containing oxyethylene linkages were prepared by the polycondensation of the diamines with diacid chlorides and tetracarboxylic acid dianhydrides, respectively. The polyamides were soluble in dimethylacetamide containing 5% of lithium chloride and dichloroacetic acid, while the polyamide-imides dissolved only moderately in the latter solvent. Thermogravimetric analysis showed that thermo-oxidative decomposition started at 310-330°C and at around 325°C for the polyamides and polyamide-imides, respectively.
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  • 2
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 783-793 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: It was found that 1-substituted quaternary imidazolium compounds show some characteristic infrared (IR) activity. On quarternization of 1-substituted imidazoles strong absorption bands appeared at about 1150 and 1550 cm-1 in the IR spectra of these compounds. The band at 1150 cm-1 was assigned to the position 2 C-H bending mode and the 1550 cm-1 band was attributed to a ring vibration mode of the quaternary imidazolium compounds. The concentration of the quaternary imidazolium units in a polymer can be determined by measuring the intensity of the absorption bands at 1150 or 1550 cm-1 in relation to another suitable absorption band of the spectrum.
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  • 3
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 131-136 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of acrylamide (M) initiated by the Ce4+/thiourea (TU) redox system has been studied in an aqueous sulfuric acid medium at 35 ± 0.2°C under nitrogen atmosphere. The rate of polymerization is governed by the expression \documentclass{article}\pagestyle{empty}\begin{document}$$R_p = K_p [{\rm M}]^{1.20} [{\rm Ce}^{{\rm 4 +}}]^{0.5} [{\rm TU}]^{0.5}$$\end{document} The activation energy is 5.9 kcal deg-1 mol-1 in the investigated temperature range 30-50°C. The molecular weight is directly proportional to the concentration of monomer and inversely proportional to the catalyst concentration. With increasing concentration of DMF molecular weight decreases. The range of concentrations for which these observations hold at sulfuric acid concentration of 2.5 × 10-2 mol/L are [monomer] = 5.0 × 10-2-3.0 × 10-1, [catalyst] = (5.0-15.0) × 10-4, and [activator] = (1.0-6.0) × 10-3 mol/L.
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  • 4
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 875-896 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ionomers prepared by the sulfonation of EPDM rubbers have been the subject of considerable investigation with regard to their remarkable bulk and solution properties; however, relatively little is known about the chemistry of the sulfonation and the structure and subsequent reactions of the sulfonated intermediates. This article reports an effort to enlarge our understanding of sulfonate ionomers by examining the chemistry of small molecule analogs of the olefinic sites which are present in low concentrations in EPDMs. Ethylidene norbornane (ENBH) and dihydrodicyclopentadiene (DCPDH) were synthesized as models for EPDMs which use ethylidene norbornene and dicyclopentadiene as their respective termonomers. The sulfonated products from the two models were quite different, a sultone with a rearranged carbon skeleton being formed in the former case and a remarkable regiospecific sulfonic acid in the latter. Conditions necessary for hydrolysis and ammonolysis were established, the former proceeding essentially by a substitution mechanism, the latter via a retro-Wagner Meerwein elimination. Rate studies showed the importance of solvent effects in these sulfonation reactions which were attributed to a combination of site reactivity and acetylsulfate solubility. Mixed solvents were effective in improving reactivity while maintaining the solvency necessary for EPDM polymers. The results of this model study are being used as a guide in studies of EPDM polymers.
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  • 5
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    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 939-950 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The grafting of styrene and acrylamide, from both their binary and unitary systems, on cellulose acetate film was studied by means of the cobalt-60 postirradiation grafting technique. The extent of grafting was found to be dependent on preirradiation dose, reaction time, and temperature, and the optimum conditions were evaluated. The effect of solvents, e.g., water, methanol, ethanol, isopropanol, and t-butanol were studied. The composition of the binary mixture as well as the nature of the alcohol used as the solvent were found to have a strong influence in modifying the course of grafting. Each component of the binary monomer mixture was found to sensitize the grafting of the other, when the former is present in relatively large concentration. The observed results are discussed in detail in terms of relative molecular reactivity and reactivity ratios.
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  • 6
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 987-995 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Four new substituted styrene derivatives carrying lactam rings (2-pyrrolidone or 2-piperidone) in para position have been synthesized, namely 4-(2-oxo-3-methylene-pyrrolidinyl)styrene, 4-(2-oxo-3-methylene-piperidinyl)styrene, 4-(p-styryl)-2-pyrrolidone, and 4-(p-styryl)-2-piperidone. Their homopolymerization and copolymerization with styrene, methyl methacrylate, and acrylic acid have been considered. By ring opening of the side lactam groups, the homopolymers are transformed into the corresponding poly aminocarboxylic acids.
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  • 7
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1271-1278 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Partially 2-carboxylbenzoyl (1) and 3-carboxyl-2-naphthoyl (2) substituted polystyrene were prepared by the Friedel-Crafts reaction of polystyrene with corresponding dicarboxylic anhydrides. Europium (III) salts of (1) and (2) and the copolymer of 4-vinylbenzoyl 2′-carboxylbenzoate-di(2-benzoyl benzoate) and styrene (5) were prepared. Polymer (5) was prepared by the copolymerization of the Eu3+ salt of 4-vinylbenzoyl 2′-benzoate and 2-benzoylbenzoate (ratio 1:2) with styrene. The fluorescence emission intensity was measured on fine powder samples. The intensity of (5) increased linearly as the Eu content increased. However, for the 1 and 2 systems the intensity reached a maximum at a Eu content as small as 0.5 wt% and remained constant when further increases were made. This phenomenon was accounted for by steric hindrance and a decrease in the freedom of bond rotation, which prevent the formation of multiple coordination linkages between Eu3+ and the benzoate groups.
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  • 8
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1331-1344 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The values of the parameters that are necessary to compute the free volume changes accompanying polymerization were determined from viscosity data of concentrated polymer solutions. Relationships applicable above and below the glass transition temperature of the polymer were quantified. A general treatment of the variation of the propagation rate constant with free volume was postulated, based on the variation of the monomeric diffusivity with free volume. This, in turn, was related to the friction coefficient of a polymer chain segment, the values of which are readily available. A discussion of the reaction behavior in the last stage of polymerization and the occurrence of limiting conversion is also presented.
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  • 9
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 997-1009 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of amylose-polyester block copolymers is described. 2,3,6-Tri-0-allyl amylose was synthesized by amylose alkoxide and allyl bromide and hydrolyzed by hydronium ions to give an hydroxyl-terminated allyl amylose oligomer (HTAA). The allyl groups were isomerized with t-BuoK to yield the prop-1-enyl isomer (HTPA). The HTPA was capped with a diisocyanate. The HTPA prepolymer was reacted with hydroxy-terminated poly(ethylene-co-propylene adipate) and poly-(ethylene terephthalate) to form block terpolymers. Block terpolymer formation was demonstrated by intrinsic viscosity increases, gel permeation chromatographic results, and infrared (IR) and PMR spectroscopy. The products were depropenylated by HgCl2 to yield amylose block terpolymers. These polymers were readily degraded by α-amylase.
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  • 10
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1389-1400 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The interaction of poly(ethylene oxide) with alkali picrates in tetrahydrofuran and dioxane was studied by optical and NMR spectroscopy and conductance measurements. Evidence was found of the formation of two kinds of solvation complex, differing in the nature of the ion pairs involved. A strong anion effect on cation binding to the polyether was demonstrated.
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  • 11
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1419-1432 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of poly(vinyl alcohol) with styrylpyridinium and quinolinium salts which contain formyl group produced water-soluble photosensitive polymers. The sensitivity was high, although the content of the styryl groups was extraordinarily low. Spectroscopical studies revealed that the high sensitivity is due to the aggregation of photofunctional group in the polymer matrix which leads to cyclodimerization on exposure to ultraviolet (UV) light.
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  • 12
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1469-1487 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of polymer-bound thiol reagents, supported on macroporous 4% divinylbenzene co-polymer (Amberlite XE-305), via three synthetic approaches is described: (i) Alkylation or acylation of XE-305 with 3-nitro-4-halogen-substituted benzyl chloride or benzoyl halide yielding 3-nitro-4-halobenzene-bound species, followed by substitution of the activated polymeric halogen atom with sulfur (see Scheme 1). (ii) Formation of a thiol ether by a direct substitution of an active polymeric halogen by reaction with benzylthiol, followed by chlorination, thiolation, and reduction (see Scheme 2). (iii) Attachment of a prepared tailor-made disulfide to aminomethyl function of a polymeric support, followed by reduction (see Scheme 3). The polymers were tested for their free-thiol content by 5, 5′-dithiobis(2-nitrobenzoic acid) (Ellman's reagent12) in DMF. Their thiolytic activity was investigated in the removal of 2-nitrophenylsulphenyl (Nps) group from Nps-protected amino acid (Scheme 4). Site-site interaction between the polymer-bound thiol with its activated halide precursor to yield polymeric sulfide during displacement reaction, and the interconversion of the polymeric thiols into polymeric disulfides at equilibrium or during reaction with Nps-amino acids, observed, and is attributed to the flexibility of the polymeric matrices.
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  • 13
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1549-1557 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Vinyl polymerizations initiated by lithium organocuprates under several conditions were investigated. It was observed that this catalyst was effective in the polymerization of specific monomers such as α,β-unsaturated nitrile and carbonyl analogues. The rate of polymerization was rapid but retarded by the addition of pyridine, nitrobenzene, or hydroquinone. Polymerization of methyl methacrylate (MMA) with lithium di-n-butylcuprate as initiator produces predominantly isotactic poly(methyl methacrylate) (PMMA) in toluene. The overall activation energy was estimated as 3.5 kcal/mol deg. Lithium di-n-butylcuprate exerts a higher stereoregulating effect on the addition of monomers than other organolithium initiators. It is proposed that polymerization proceeds via a coordinated anionic mechanism.
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  • 14
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1587-1598 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of a new class of piezoelectrically active materials comprised of various co- and ter-polymers of tributyltin methacrylate (TBTM) and trimethyltin methacrylate (TMTM) are described. In this article films of the various polymer compositions were evaluated for tin content, glass transition temperature (Tg), and crystallinity or “ordering” of the amorphous phase. A brief theory of piezoelectricity in polymers will be given in Part II with a description of sample preparation, poling techniques, and the measurement system, as well as piezoelectric evaluation results.
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  • 15
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1629-1638 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Insoluble complexes are formed in acidic aqueous media when poly(acrylic acid) (PAA) and poly-(vinylbenzo-18-crown-6) (P18C6) or polyvinylbenzoglymes are mixed. Complex formation results from hydrogen bonding between carboxyl groups and crown ether- or glyme-oxygen atoms as well as from hydrophobic interactions. The precipitation is pH dependent and was determined as a function of the ratio PAA to P18C6 or to polyglyme at different HCl concentrations in 10-4M solutions of polycrown or polyglyme. Precipitation is nearly quantitative in 0.01N HCl. The compositions of PAA/P18C6 precipitates were determined as a function of the initial PAA/P18C6 ratio in solution. The complexes with P18C6 can be solubilized in acidic media when crown-complexable cations (K+, Cs+, Ba2+) are added, but the charged P18C6 reprecipitates in basic solution as a polysalt complex with the PAA-polyanion. More stable PAA-P18C6 complexes in the form of fibers can be obtained by interfacial complex formation. Poly(methacrylic acid) is less effective as a complex former.
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  • 16
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1653-1667 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Acrylonitrile-,4-vinylpyridine copolymers were prepared in chloroform solution at 60°C with AIBN as initiator. Copolymer compositions were determined from their 15.01-MHz 13C-NMR spectra. Reactivity ratios of rAN = 0.093 and r4VP = 0.32 were calculated by the Kelen and Tudos method. The run number, number-average sequence lengths, and monomer sequence distributions were also calculated. The Tg values of the copolymers, their dye uptake, and degree of alkaline hydrolysis were influenced by the overall copolymer composition but particularly by the monomer sequence distribution in the copolymers.
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  • 17
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1709-1716 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Radiation-induced cationic polymerization of styrene was studied in methylene chloride in the presence of triphenylsulfonium hexafluorophosphate. Acceleration in polymerization and an increase in molecular weight at a low temperature (-78°C) were observed in the presence of triphenylsulfonium salt. A study of pulse radiolysis revealed that both effects are due mainly to PF-6, which forms ion pairs with the cationic species involved in the polymerization.
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  • 18
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2555-2564 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Lithium-metallated styrene-p-benzylstyrene copolymer was reacted with the branched polymer with chlorine groups at the pendant chain ends (multifunctional branched polymer) in tetrahydrofuran (THF) at 25°C. The rate constant was estimated from the changes in the concentration of metallated polymer by using photometrical measurements. The various reaction conditions were chosen and it became clear that the rate constants of intermolecular (k20) and intramolecular (k3intra) crosslinkings were derived separately at the second stage. k20 showed a constant value in spite of the molecular weight of crosslinker chains and was about equal to the rate constant of the grafting. The rate of intramolecular crosslinking at the second stage increased with decreasing the molecular weight of pendant chains of multifunctional branched polymer.
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  • 19
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2575-2602 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymers containing pendant acetylacetonate (acac) groups suitable for crosslinking through metal complex formation are described. Diene-based copolymers, polystyrene, and polydimethylsiloxane, each containing a measurable number of acac groups distributed along the chains, were synthesized. The polymers were studied both for the amount of acac ligand and for their crosslinking reactions with selected transition metals by ultraviolet (UV) second-derivative spectroscopy. The UV analyses of the polymer systems were compared with their monomer analogs, and the results confirm that the crosslinking chelation reactions of polymer compounds are similar to those of model compounds. Homogeneous chelate crosslinking conditions were developed by using transition-metal salts such as Cu(laurate)2, Fe(laurate)3, and Cr(laurate)3 in solvents such as chloroform and benzene. Polymeric ligands containing 1-5% acac in solution at various concentrations were reacted to form both inter- and intramolecular crosslinkages. The kinetic stability of the chelate crosslinks has been studied by a unique ligand exchange-gel solubility relationship.
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  • 20
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1833-1846 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The double probe method was applied to plasma of tetrafluoroethylene (TFE) and ethylene and the electron temperature (Te) and density of positive ions (np) were measured at various discharge wattages. The probe current-probe voltage diagrams for TFE were different from those for ethylene. The shape of its diagram indicates that a considerable number of negative ions exist in TFE plasma. The levels of np for TFE were also nearly six times greater than those for ethylene at the same discharge current. The dependence of TFE polymer deposition and the chemical structure of the polymer, based on ESCA data on discharge current, was related to Te and np measured by the probe method. The values of Te and np may not be directly related to the polymer formation in a plasma; the method provides a direct measure of plasma energy density where plasma polymerization takes place, whereas it cannot be accurately estimated by the input energy of a discharge. It was found that plasma energy density based on (npTe) for TFE plasma and that for ethylene differ significantly at the same level of input parameter (W/FM), where W is the discharge wattage, F is the volume flow rate, and M is the molecular weight of the monomer.
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  • 21
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1885-1897 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This article describes a new, spontaneous, 1:1 alternating copolymerization between a Schiff base, N-benzylidine aniline (NBA), and α-haloacrylic acids (XAA) such as α-chloroacrylic acid (ClAA) and α-bromoacrylic acid (BrAA). The structure of the copolymers was identified by nuclear magnetic resonance (NMR) and infrared (IR) spectra. By using the isolation method we determined the order of each monomer. On the basis of kinetic studies, a mechanism that involves initiation, propagation, and termination by zwitterion is proposed. The effects of copolymerization under various conditions were studied and the intrinsic viscosity and number-average molecular weight were measured. The overall energy of activation, ERp, for the copolymerization was determined and thermal degradation studies were made.
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  • 22
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 23
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1965-1970 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 24
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2765-2772 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Charge transfer (CT) interaction is described in semiconducting dispersions of TCNQ complex salt \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm Et}_3 {\rm NH}^+ ({\rm TCNQ})_2^{\cdot^{\hskip-3.7pt\hbox{--}}}$\end{document} with and without added TCNQ°, in poly(vinyl acetal) matrices in which the electron-donor moiety is varied. The extent of CT interaction was determined in films and in solution (DMF, acetonitrile, or methylene chloride) through the absorbances at 398 nm (\documentclass{article}\pagestyle{empty}\begin{document}$ {\rm TCNQ}{\ }^{\cdot^{\hskip-3.7pt\hbox{--}}}$\end{document} and TCNQ°) and 857 nm \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm TCNQ}{\ }^{\cdot^{\hskip-3.7pt\hbox{--}}}$\end{document}. Resistivity of the conductive films was related to the stoichiometry of TCNQ species in the films and found to have a minimum at \documentclass{article}\pagestyle{empty}\begin{document}$[{\rm TCNQ}^\circ]/[{\rm TCNQ}{\ }^{\cdot^{\hskip-3.7pt\hbox{--}}}]\simeq 1$\end{document}. Lower resistivities were attained with films having a uniform, densely packed dispersion of microcrystallites which were obtained at a relatively slow solvent removal rate. With this particular complex salt, strong electron-donor polymers are found to be better matrices for semiconductivity.
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  • 25
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2829-2838 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of methacryloyl fluoride (MAF) homopolymerization was investigated in methyl ethyl ketone (MEK) with azobis(isobutyronitrile) as initiator. The rate of polymerization (Rp) followed the expression Rp = k[AIBN]0.55[MAF]1.18. The overall activation energy was calculated as 74.4 kJ/mol. The relative reactivity ratios of MAF(M2) copolymerization with styrene (r1 = 0.083, r2 = 0.14), and methyl methacrylate (r1 = 0.48, r2 = 0.81) in methyl ethyl ketone were obtained. Application of the Q-e scheme (in styrene copolymerization) led to Q = 2.22 and e = 1.31. The glass transition temperature (Tg) of poly(MAF) was 90°C by thermomechanical analysis. Thermogravimetry of poly(MAF) showed a 10% weight loss of 228°C in air.
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  • 26
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2879-2885 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Relatively high-molecular-weight segmented polyurethanes based on methylene bis(4-phenyl-iso-cyanate), poly(propylene glycol), butane-1,4 diol, and cis-2-butene-1,4 diol have been synthesized and characterized. These unsaturated polyurethanes were successfully grafted using N-vinyl pyrrolidone as monomer and 2,2′-azobisisobutyronitrile as free-radical initiator. However, grafting experiments involving benzoyl peroxide as initiator were unsuccessful. The graft copolymers were isolated from the ungrafted polyurethane and poly(N-vinyl pyrrolidone) by selective solvent extraction. Elemental microanalysis, IR, NMR, thermogravimetric analysis, and equilibrium water sorption measurements were used to characterize the graft copolymers.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2863-2878 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The formalized kinetic approach to the mechanism of urethane formation in the system of prepolymer with end NCO groups-1,4-butanediol together with the dispersion analysis of kinetic curves have helped to establish that, at moderate temperatures, the mechanism may be represented by a scheme comprising a noncatalytic stage of urethane formation and a catalytic one including the formation of a double complex of a catalyst with an isocyanate or a hydroxyl group. As the temperature rises the proportion of the noncatalytic stage decreases significantly, while a mechanism, including the formation of the triple complex isocyanate group-catalyst-hydroxyl, becomes the most probable. It has been shown that the formation of a triple complex at elevated temperatures is thermodynamically more advantageous than the formation of double complexes; hence these changes of mechanism with temperature. It has been found that the temperature conditions of polyurethane production greatly affect the degree of its branching. Two crosslinked polyurethanes were obtained, one under the temperature conditions providing for the minimum degree of branching, the other under isothermal conditions. It has been discovered that the degree of branching of a prepolymer may greatly affect the density of chemical and physical bonds and a range of physical and chemical properties of the polyurethane.
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  • 28
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2915-2934 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Based on modern concepts of ionic polymerization, a system of kinetic models which covers various initiation and propagation mechanisms, all based on a pseudo-steady-state assumption, is proposed. Special attention is given to the effect of solvent on the rate-controlling steps. Equations for reaction rate, degree of polymerization, and molecular weight distribution for 12 fundamental models are derived and fully discussed. The theory is also extended to more complicated systems such as the ion pair, free-ion system.
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  • 29
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2989-2993 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 30
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3115-3120 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of vinyl acetate in N,N-dimethylformamide (DMF) at 60°C initiated by AIBN in the presence of [Fe(DMF)6](ClO4)3 and Fe(N3)3 had been studied. Fe(N3)3 was produced in situ by mixing solid sodium azide (NaN3) and hexakis(N,N-dimethylformamide) iron (III) perchlorate, [Fe(DMF)6](ClO4)3, in the ratio of 3:1. The velocity constant kx for the interaction of poly(vinyl acetate) radical with [Fe(DMF)6]3+ was found to be 1.44 × 103L mol-1 s-1 and that for the interaction of poly(vinyl acetate) radical with Fe(N3)3 to be 3.44 × 105 L mol-1 s-1 at 60°C.
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  • 31
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3107-3114 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyethylene films were evaporated in gas plasmas of Ar, N2, O2, and H2O. The deposits were analyzed by infrared (IR) spectroscopy to determine the concentration of characteristic functional groups. The deposit prepared in Ar-atmosphere had a rather high concentration of methyl group and many double bonds were produced in the film. The deposits prepared in Ar- and N2-plasmas produced similar spectra, which showed twice the concentration of methyl group than the deposit in Ar-atmosphere and also contained a few carbonyl and hydroxyl groups. The film treated in O2-plasma contained the largest amount of carbonyl group and the lowest number of double bonds among the plasma-treated deposits. Dielectric loss curves against temperature for the deposits treated in these plasmas showed a broad peak near 20°C. For O2-plasma-treated film the loss tangent curves showed a sharp maximum. The activation energy for the relaxation of Ar-, O2-, and H2O-plasma-treated films had the same value of 50.6 kcal/mol. The observed relaxation in the films prepared in gas plasmas was considered due to the β process and was attributed to the motion of oxidized branched polyethylene.
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  • 32
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3131-3146 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Hydroxy-terminated polysulfones (PSs) of number-average molecular weights from 3000 to 26,000 g/mol were converted to the corresponding 4-ethynylbenzoate-terminated PS through a three-step synthesis. The initial step involved the reaction of the hydroxy precursor with 4-bromobenzoyl chloride followed by displacement of the bromo group with trimethylsilylacetylene using a palladium catalyst. The trimethylsilyl group was subsequently cleaved with a weak base to afford the ethynylbenzoate-terminated PS. A more direct route to the ethynylbenzoate-terminated PS involved the reaction of the hydroxy-terminated PS with 4-ethynylbenzoyl chloride. The trimethylsilylethynyl and ethynyl groups undergo a thermally induced reaction to provide modified PS with better solvent resistance and higher apparent glass transition temperatures than an unmodified linear PS. The physical properties of the modified PS are compared with those of a linear PS.
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  • 33
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3421-3429 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The rate of reaction of 1-halooctanes with aqueous sodium cyanide catalyzed by phosphonium salts attached to insoluble polystyrene resins by tetramethylene or heptamethylene spacers was studied as a function of catalyst particle size, degree of polymer crosslinking, percentage of ring substitution, and temperature. Rates of reaction of 1-bromooctane with 17-38% ring-substituted catalysts increased as spacer-chain length increased. Rates of reaction of 1-bromooctane decreased, whether the percentage of ring substitution increased or decreased from 17-19%. Rates of reaction of 1-chlorooctane increased with increasing spacer-chain length and decreasing percentage of ring substitution. Apparent activation energy for the reaction of 1-bromooctane with 9% ring-substituted, spacer-modified catalysts was 9-10 kcal/mol and 13 kcal/mol with 17-19% ring-substituted catalysts. The hydrophilicity of catalysts decreased with increasing spacer-chain length and decreasing percentage of ring substitution. The mechanisms of reaction were discussed in terms of intrinsic reactivity and intraparticle diffusion limitations on the reaction rates.
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  • 34
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1-15 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal decomposition of this resin was examined by quantitative pyrolysis - gas chromatography. The decomposition does not follow the Hurd-Blunck mechanism generally obeyed by beta-hydrogen containing esters. Instead, phthalic anhydride is extruded almost quantitatively. It is proposed that the mechanism involves the rearrangement of the phthalate C—O bonds to extrude the anhydride, leaving a maleic acid - dipropylene glycol polyester chain.
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 31-39 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N-grafted poly(p-phenylene terephthalamide)s (PPTA) were synthesized from PPTA and acrylonitrile or propylene oxide via metalation in a solution of the polymer in a sodium methylsulfinylcarbanion-dimethyl sulfoxide solvent at low temperatures. The introduction of these branches into the amide groups of PPTA increased solubility but decreased thermal stability. The effects of the branches on thermal properties and solubility are discussed. The structure of the graft copolymers is described on the basis of wide-angle x-ray diffraction, infrared spectra, and solubility.
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  • 36
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 73-81 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymerization of acrylonitrile initiated by a potassium superoxide (KO2)-nitrobenzene system was carried out in anhydrous dimethylsulfoxide (DMSO) at 25°C. The initial rate of polymerization was rapid and a high-molecular-weight polymer was obtained. The molecular weight was proportional to monomer concentration and inversely to concentration of initiator within 5 min. The overall activation energy was estimated as -2.6kcal/mol deg in the temperature range of 20-50°C. In addition to nitrobenzene anion radical, other anion radicals generated by one-electron transfer from KO2 to charge transfer agents such as m-dinitrobenzene benzoquinone, benzophenone, and naphthalene were effective in the polymerization of acrylonitrile. It is proposed that polymerization proceeds via an anionic mechanism that involves one-electron transfer from anion radicals to monomer.
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    Notes: Conditions for the convenient synthesis of linear poly(β-pinenes) that carry one or two tert-chloro end groups (∼Clt) and three-arm star poly(β-pinenes) that carry three termini have been worked out. Specifically, the polymer with one ∼Clt end group was prepared by the H2O/BCl3 system, whereas those with two and three ∼Clt termini were prepared by the use of p-dicumyl chloride and sym-tricumyl chloride/BCl3 inifer combinations. The ∼Clt-terminated polymers were dehydro-chlorinated to yield the corresponding olefins. The molecular weights of the products were low enough to permit infrared (IR) and quantitative 1H-NMR investigations. Poly(β-pinene-b-tetrahydrofuran) diblock copolymers have been synthesized by inducing the polymerization of tetrahydrofuran (THF) by the Pβ—Clt/AgCF3SO3 initiating system.
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  • 38
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 97-109 
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    Keywords: Physics ; Polymer and Materials Science
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    Topics: Chemistry and Pharmacology
    Notes: Diaryliodonium salts (I) undergo efficient thermal decomposition in the presence of copper (II) compounds. Such systems can be employed as a novel class of latent thermal initiators for cationic polymerization. An investigation of the mechanism of the reaction demonstrated that the copper (II) compound is first reduced to the corresponding copper (I) compound, which subsequently reduces the diaryliodonium salt. The cationic polymerization of some typical monomers using these new initiators was carried out to demonstrate the scope of their utility.
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 147-154 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: It has been found that when hydrophobic monomers are polymerized in the presence of highly hydrophilic polymer seed particles, the second-stage hydrophobic polymers form cores surrounded by the first-stage hydrophilic polymers, resulting in “inverted” core-shell latexes. The formation of core-shell morphology by this inversion process has been found to be dependent on the hydrophilicity and molecular weight of the first-stage hydrophilic polymers and the extent of phase separation between the two polymers involved. Particle morphology has been examined by electron microscopy, surface acid titration, alkali swelling of particles, and surface reactivity.
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  • 40
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 155-163 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The structure of polymeric microemulsions, viz. toluene/water/PS-PEO graft copolymer/2-propanol, has been studied by 1H-NMR spectroscopy. Results show that at low water contents, the copolymer adopts a rather diffuse micellar structure in which the rotational mobility of the ethylene oxide units is little affected by the ternary solvent mixture. Above a critical water concentration (ca. 4%), a restriction in mobility of the ethylene oxide chains is observed which has been related to the formation of an inverse micellar structure with water solubilized within the particles. The study of the chemical shifts and linewidths of water protons indicates that initially most of the water is hydrogen bonded to the hydrophilic part of the copolymer, then is present in its free form in water aggregates. These results confirm previous data obtained by dialysis equilibrium experiments.
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  • 41
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 25-34 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of thermal degradation of a sample of 46.0% isotactic polyvinyl bromide (PVBr) was studied in a static procedure. An integrated analytical method is presented for the estimation of rate constants. Reaction curves for the formation of hydrogen bromide (HBr) can be interpreted in terms of two concurrent first-order reactions; namely, with activation energies of 29.7 and 40.6 kcal/mol, respectively. The mathematical derivation does not involve an approximation; thus the accuracy of the procedure depends only on the experimentation. Good agreement between calculated and experimentally determined values of a series of characteristic kinetical parameters was obtained. The formation of HBr from PVBr was studied kinetically by a thermogravimetric programmed procedure at room temperature to 700°C. By this method it is possible to determine the activation energy of the stripping process of the main chain without knowing the form of the kinetic equation. The activation energy of 40.1 kcal/mol for the overall process was evaluated by the MacCallum and Tanner method. This dynamic heating developed two distinct temperature regions in which maximum rate loss occurred at characteristic temperatures. The first temperature region was associated with the quantitative evolution of 100% HBr molecules.
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  • 42
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 73-78 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The photoinitiation efficiency of the free-radical polymerization of methyl methacrylate and styrene by several carbonly compounds has been determined. The compounds considered were α-substituted ketones and α-dicarbonyl compounds. For the ketones, the initiation efficiency employing methyl methacrylate depends on the α substitution; the values obtained change from less than 10-3 (acetone) to 0.65 (3-hydroxy-3-methyl-2-butanone). All ketones are more efficient towards methyl methacrylate than styrene. This result can be explained in terms of triplet quenching by the last monomer. The results obtained employing α-dicarbonyl compounds do not conform to a simple pattern. In particular, benzil shows a considerably larger efficiency towards styrene than for methyl methacrylate. Since benzil is efficiently quenched by styrene, the initiation must involve the interaction of an excited benzil molecule and the monomer.
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  • 43
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 109-118 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reduction of an electroactive polymer at an electrode involves the transfer of a large number of electrons to a single molecule. A quantitative study of this process indicates whether the system behaves ideally. The electron transfer process in polyvinylbenzophenone and in polyvinylbenzophenone-co-styrene in N,N-dimethylformamide solution was investigated by voltammetry at a rotating disk electrode. It is concluded that benzophenone (BP) groups attached to the polymer backbone are noninteracting electroactive centers and that every BP group is reducible at the electrode. The relationship between limiting current and molecular weight was examined quantitatively for a series of polymers of low dispersity with molecular weights ranging up to 300,000, and with a controlled, varied content of electroactive groups. The diffusion coefficient was determined as a function of molecular weight from the electrochemical data, and was found to be in good agreement with the theoretical model based on transport properties. The dependence of the diffusion coefficient on concentration of polymer and on temperature were investigated and activation energies determined.
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  • 44
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 147-157 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Styrene has been copolymerized with low percentages of p-vinylbenzophenone-p′-tert-butyl perbenzoate (VBPE). The resulting copolymer has been used to make graft copolymer with methyl methacrylate using UV irradiation (366 nm). The grafting efficiency has been observed to increase with time of irradiation and percentage of VBPE in the copolymer. The copolymer has also been observed to crosslink efficiently with photochemical irradiation.
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    Topics: Chemistry and Pharmacology
    Notes: A note has appeared which seeks to question work from these laboratories (which appeared in 1964). The author of this recent paper attempts to demonstrate that the ΔH and ΔS values, based on our results, for the dissociation of the polyisoprenyllithium dimer “have no meaning.” This assessment ignores information in the literature. For similar reasons, other claims by the author of this recent paper are shown to be subject to scrutiny.
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  • 46
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 227-231 
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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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  • 47
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 253-256 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 269-275 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A novel class of poly(metal phthalocyanino) benzimidazoles were prepared by the condensation reaction between metal (Cu, Co, and Zn), 4,4′,4″,4‴-tetracarboxyphthalocyanine, and 3,3′-diaminobenzidine. The reaction was investigated by melt and solution condensation methods. These polymers showed excellent thermal and thermooxidative stability and are noteworthy for their high char yield (86-90%) at 800°C in an anerobic atmosphere. Elemental analyses, spectra, and TGA studies were used to characterize these materials. Isothermal gravimetric analyses were carried out to determine their long-term thermal stability.
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  • 49
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 335-342 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New phenoxaphosphine-containing polyester-imides were prepared by the interfacial polycondensation of a dichloroformyl-phenoxaphosphine derivative containing a preformed imide ring with five bisphenols. The polymerizations, which were carried out in a chloroform-aqueous sodium hydroxide mixture, afforded polyester-imides with reduced viscosities of 0.60-1.55 dL/g in 61-95% yields. The preformed imide ring did not undergo hydrolysis under the polymerization conditions. Several of the polymers were soluble in chloroform and could be cast into flexible and transparent films. The phenoxaphosphine-containing polyester-imides have good thermal properties, exhibiting little decomposition below 400°C. They appear to be more thermally stable than phenoxaphosphine-containing polyesters, but are not as thermally stable as the corresponding polyimides and polyamide-imides. The order of thermal stability for phenoxaphosphine-containing polymers in air is polyimide ≳ polybenzoxazole 〉 polyamide-imide ≳ polybenzimidazole 〉 polyester-imide 〉 poly-1,3,4-oxadiazole ≳ polyamide 〉 polyester. The polyester-imides exhibited self-extinguishing behavior.
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 751-760 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The concept of piezoelectric and pyroelectric effects in amorphous polymers is presented, with experimental results, details on sample preparation, and activity evaluation. Most evaluations were performed on 25-30 mol% tributyltin methacrylate/methyl methacrylate copolymers, which possessed good piezoelectric activity, antifouling properties, and paint-formulation characteristics. Solvent-induced orientation effects that lead to piezoelectric activity in amorphous, unpoled, polymers are also described.
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 737-750 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The physical state of the material obtained during the various stages of preparation of a typical MgCl2-supported, high-mileage propylene polymerization catalyst was studied by BET, mercury porosimetry, and x-ray diffraction techniques. The starting MgCl2 and the substance after HCl treatment have negligible BET surface areas. Mercury porosimetry showed that they have large pores with radii 〉 200 nm which are probably crevices between MgCl2 crystallites. The most pronounced physical changes occur during dry porcelain ball milling in the presence of ethyl benzoate. After 60 h or more of ball milling the material had a 5.1-7.3 m2 g-1 BET surface area, twice the pore surface area, and a smaller pore radius than before ball milling and a large reduction in crystallite sizes to almost ultimate dimensions. The crystallites were probably held together by complexation with ethyl benzoate in the form of large agglomerates. Subsequent reactions with p-cresol and triethyl aluminum had minor effects in further reduction of the MgCl2 crystallite size but efficiently brokeup the agglomerates. The final refluxing with TiCl4 increased the BET surface area to 110-150 m2 g-1 but may have increased the crystallite size somewhat due to cocrystallization of TiCl3 and AlCl3 with MgCl2. There may have been only 8-10 crystallites in each catalyst particle. The surface structure of the catalyst resembled those of the classical Ziegler-Natta γ-TiCl3·0.33 AlCl3 catalyst.
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  • 52
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 111-120 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reactions of 4-aminophthalonitrile (APN) with 3,3′,4,4′-benzophenone tetracarboxylic dianhydride (BPTDA), and with 1,2,3,4-benzenetetracarboxylic dianhydride (PMDA) have been studied to optimize the conditions for the synthesis of monomeric thermosetting bisphthalonitrile compound. Suitable procedures for the synthesis of the two monomers are presented. Elemental analyses, IR spectra, dynamic thermogravimetric analyses, differential scanning calorimetry, 1H-NMR, and mass spectral studies have been used to characterize these compounds. Preliminary observations show that these materials can be polymerized to give high-temperature-resistant materials.
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  • 53
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 141-145 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This article is a report of the investigation of the influence of monomer composition within optimum limits on the light-transmitting properties of MBS terpolymers obtained by the mass-suspension method. The high and nearly constant light-transmitting properties of the MS copolymer matrix have no effect on the light-transmitting properties of MBS with a MMA content up to about 20 mol % higher than that at the azeotropic point. The refractive index of the MS copolymers decreases uniformly as the mole ratio of MMA increases and becomes equal to the index of the SBR. Particle concentration in sizes up to 0.6μm increases as the MMA content increases to a given point at which the concentration remains constant as MMA continues to increase. The light-transmitting properties of MBS with a MMA content of 57 mol % are improved significantly. This fact is explained by a decrease in variation on the refractive index between the two phases to 0.0014 and by the increasing percentage of particles with sizes smaller than 0.6 μm up to 70%.
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 175-181 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: It was found that aromatic aldehydes and ketones could be reduced smoothly at room temperature by sodium dithionite using viologen derivatives as an electron transfer catalyst to obtain the corresponding alcohols in good yields. Viologens (methyl viologen and polymer) acted catalytically and active species in the reduction were quinoid forms which were obtained by two-electron reduction of viologens.
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  • 55
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 953-960 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: For a fundamental study of the electrochemical behavior of electroactive polymers a series of poly(3-vinyl-10-methylphenothiazine) (polyMPT), copolymers of 3-vinyl-10-methylphenothiazine and methyl methacrylate (MMA) (copolyMPT), and 3-ethyl-10-methylphenothiazine (EMPT) (a related monomer model) were prepared. The methylphenothiazine groups in these compounds showed reversible, one-electron oxidation waves in the triangular-were voltammograms. From a detailed comparison of the voltammograms between these polymers and EMPT it was revealed that the electroactive groups in poly MPT were not the “noninteracting” centers in the strict sense, whereas those in copolyMPT, in which the centers are spaced with the MMA segments, were typically noninteracting in nature; that is, in polyMPT the oxidation takes place at the potential 40 m V lower than that of EMPT and copolyMPT exhibited a wave identical to that of EMPT in shape and potential. The exhaustive electron transfer occurred from polyMPT to the electrode. On the other hand, a significant number of centers remained unoxidized in copolyMPT. The self-exchange electron transfer within the polymer coil facilitates the exhaustive oxidation. For this event the proximity of the centers was an essential factor.
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  • 56
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 969-983 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Substantial hole transport can be achieved in organic polymers simply by incorporating aromatic amine groups into the monomer. Hole mobilities similar to or greater than those in poly(N-vinyl-carbazole) (PVK) were measured in a series of high molecular weight arylamine-substituted polymethacrylates. The hole transport in these polymers is electric-field-dependent as in PVK, varying between E and E2 within a range of 4 × 104 - ∼9 × 105 V/cm. The polymers also exhibit carrier generation in ultraviolet (UV) light in the range of absorption. Synthesis of the monomers, their polymerization, and the general properties of these polymers are discussed.
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  • 57
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1025-1032 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermally stable poly(metal phthalocyanine)imide copolymers were prepared with metal(11) 4,4′,4″,4‴ -phthalocyanine tetraamines, 4,4′ -diamino diphenyl ether, and 3,3′,4,4′ -benzophenone tetracarboxylic dianhydride. Variables such as molar concentrations of the reagents, solvents, and temperature were investigated to optimize the conditions of the polymerization. Inherent viscosity, and infrared (IR) spectral and thermogravimetric analysis (TGA) studies were done to characterize the polymers. These polymers are stable and thier decomposition temperatures both in air and nitrogen are greater than 500°C. Their char yields at 800°C in nitrogen varied between 60 and 76%, depending on the type and concentrations of the metal phthalocyanine tetraamines. These polymers can be used to produce heat-stable films, fibers, varnishes, and adhesives.
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  • 58
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 923-936 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The influence of the reaction conditions (time, temperature, concentrations of the monomer, and the initiator) on the amount and composition of the oligomers and high molecular products formed during the heterogeneous anionic polymerization of ∊-caprolactone was investigated. The polymerization was initiated by KC24 in xylene or tetrahydrofuran. Conditions were found under which intra- and intermolecular transesterification was strongly suppressed, thus providing the opportunity for the formation of polyesters with viscometric molecular masses of more than 300,000 and good yields (80% and higher). The total quantity of products with a viscometric molecular mass below 2500 did not exceed 15%; that of the cyclic dimer was not in excess of 5%. Peculiar features of the KC24 initiated polymerization are the insignificant rise in the number of oligomers and the formation of high polymers even in strongly diluted solutions of ∊-caprolactone (0.2 mol/L and lower). The quantity and molecular mass of the polymers obtained decreased as the temperature increased. It was also established that the polymerization of the cyclic dimer of ∊-caprolactone is not initiated by KC24.
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  • 59
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 775-782 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Spin-lattice relaxation times and nuclear Overhauser enhancements (NOE) for 13C nuclei in copolymers of acrylonitrile and vinylidene chloride were measured at 20.1 and 67.9 MHz. In the —CCl2— region of the spectrum T1 and NOE values of the various resonances are equal within experimental error and are invariant to changes in composition. The T1 and NOE values of the —CCl2— region, however, are not equal to those of the —CH— or —CN region. As a result compositions cannot be calculated by direct comparison of the areas in the —CCl2— region and either the —CH— or the —CN region. Discrepancies can be corrected for the —CH— resonances by multiplication of the area by an empirical constant. A similar constant for the —CN region is composition-dependent at 20.1 and 67.9 MHz. A chemical shift anisotropy mechanism is postulated as important for relaxation of the —CN resonances. The overall influence of variable T1 and NOE values on quantitative determination of polymer composition is considered.
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  • 60
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1151-1157 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyaromatic either-sulfone-ketones containing fluoro-substituted p-cyclophane units were prepared from isophthaloyl chloride, terephthaloyl chloride, diphenyl ether, diphenoxydiphenyl sulfone, and a small amount of 1,1,2,2,9,9,10,10-octafluoro-[2,2]-p-cyclophane (type A) or pseudo-p-1,12,2,9,9,10,10-octafluoro-[2,2]-p-cyclophane bis-acid chloride (type B) by Friedel-Crafts-type polymerization. The p-cyclophane units were incorporated as crosslinking sites. Crosslinking was achieved by curing polymers at 300-350°C for several days. The polymers obtained, containing 1-10 wt % fluoro-substituted p-cyclophane units, were moderately soluble in dichloromethane, DMF, and sulfuric acid with inherent viscosities between 0.4 and 0.6. Laminates on glass fiber were made with excellent thermal stability.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 897-899 
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    Keywords: Physics ; Polymer and Materials Science
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    Topics: Chemistry and Pharmacology
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  • 62
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 929-938 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Studies of the effect of aqueous Br2 solution on the fine structure of cellulose have shown that the accessibility of the cellulose is a complex function of the duration of treatment. Following immersion of rayon-cellulose in the Br2 solution, its accessibility is observed to increase until a peak is reached, after which the accessibility decreases with time. For higher temperatures and greater concentrations of Br2, a sharper peak and faster rates of increase and decrease of accessibility are obtained. In order to explain this behavior, a mathematical model of the kinetics is postulated involving two opposing first-order processes occurring simultaneously. One process describes the decrystallization of crystalline regions within the cellulose by opening intermediate linkages due to Van-der-Waals forces involved. The second process relates to the crystallization of the less-ordered regions. The rate constants for these processes are determined by fitting experimental curves to the postulated analytical expression with the aid of a digital computer program. Experiments carried out on high-modulus rayon showed that for this type of cellulose, the effect described above was very pronounced. From the calculated rate constants, the activation energies of the crystallization and decrystallization reactions were determined. The plots of the rate constants versus 1/T showed that a break occurs at 25°C, corresponding to a second-order transition point of cellulose. The energies of activation of the crystallization process are in the range of 7-9 and 10-13 kcal/mol in the temperature ranges 10-25 and 25-40°C, respectively. The activation energies of the decrystallization process are 13 and 18-24 kcal/mol in these temperature ranges.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 977-986 
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    Topics: Chemistry and Pharmacology
    Notes: Alternating copolymers of α-methylstyrene (α-MeSt) and maleic anhydride (MAn) were prepared by free-radical-initiated polymerization in bulk, benzene, or butanone as solvents. By applying the generalized model described by Shirota and co-workers, the reactivity ratios k1c/k12 and k2c/k21 were calculated from the change of copolymerization rate with monomer feed at constant total monomer concentration. From the equation Rp = Rp(f) + Rp(CT) were calculated Rp(f) and Rp(CT), and it was found that in benzene the reaction proceeds predominantly by the addition of CT-complex monomers, while in butanone, cross propagation of free monomers predominates. Termination occurs predominantly by homotermination of α-MeSt macro free radicals, kt22, although the cross termination kt21 is also operative.
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1289-1303 
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    Keywords: Physics ; Polymer and Materials Science
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    Topics: Chemistry and Pharmacology
    Notes: The esterification of the carboxyl group in copoly(γ-benzyl-L-glutamyl-L-glutamic acid) was carried out using N-hydroxysuccinimide and dicyclohexylcarbodimide to yield the activated site for the coupling reaction with amino compounds. The α-helix stability of the reactive copolymer thus obtained is remarkably affected in the presence of succinimide ring. This copolymer was proved to react nearly completely with amino alcohols such as 2-aminoethanol, 3-aminopropanol, and diethanolamine. The copoly(N5-hydroxyalkyl-L-glutamine) thus prepared is insoluble in water, since the benzyl ester remains in this copolymer. The copoly(α-amino acids) having another functional group were also prepared using aminoalkylsilane. Crosslinked poly(α-amino acids) were prepared by the reaction of the reactive copolymer with a low-molecular-weight polymer of PBLG having one amino group on each end of its main chain which was obtained from the corresponding NCA using p-diaminobenzene as an initiator. Another crosslinked polymer was prepared using an alkyl diamine such as 1,6-diaminohexane or 1,12-diaminododecane as a crosslinking reagent. The crosslinked copoly(α-amino acids) bearing the activated site are able to further react with various compounds having amino groups.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1089-1095 
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    Topics: Chemistry and Pharmacology
    Notes: Pyrrole reacted with potassium persulfate in aqueous media to form polymers or “pyrrole blacks.” The structure and molecular weight depend on the initial pyrrole/K2S2O8 ratio. An ESR line due to trapped electrons or free radical ions appeared at g = 2.0036 (width 3.6 G) in all products and its intensity decreased with an increase in initial concentration of potassium persulfate.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1139-1141 
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    Keywords: Physics ; Polymer and Materials Science
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    Topics: Chemistry and Pharmacology
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1417-1422 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reversible isomerization of poly(chloromethylthiirane) and poly(3-chlorothietane) represents a new kind of polymer reaction and a new method of copolymer synthesis. In chloroform, in dichloromethane, or in nitrobenzene the reaction is well described by reversible first-order kinetics. A rate increase of ca. 40% on changing the solvent from chloroform to nitrobenzene is consistent with an isomerization mechanism that involves a rate-determining attack of the backbone sulfur atom on the neighboring carbon-chlorine bond and rapid ring-opening of the thiiranium ion intermediate by chloride ion.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1203-1211 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the aqueous polymerization of methyl methacrylate by a ceric-thiourea initiator system in moderately acid solution (pH 2.15) was studied. The rate of polymerization was proportional to 0.41 power of ceric concentration, 0.32 power of thiourea concentration, and 1.18 power of monomer concentration. The degree of polymerization was smaller than expected from the rate of polymerization. Initiation efficiency was less than one. There was no evidence of any ceric ion termination in the concentration range of 2.50 × 10-4-2.00 × 10-3M studied. The results are explained in terms of partial primary radical termination; the principal mode of termination, however, was bimolecular.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1261-1270 
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    Keywords: Physics ; Polymer and Materials Science
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    Topics: Chemistry and Pharmacology
    Notes: The effect of chain transfer agents on the nucleation and growth of polymer particles in the emulsion polymerization of styrene were examined extensively. The chain transfer agents used are carbon tetrachloride, carbon tetrabromide, and four primary mercaptans (C2, n-C4, n-C7, and n-C12). It is shown that with an increase in the amount of chain transfer agents charged the rate of polymerization per particle decreases progressively. The number of polymer particles formed, on the other hand, increases initially then decreases. These effects can be enhanced by using a chain transfer agent with higher values of chain transfer constant and solubility in water. It is also demonstrated that with increasing radical desorption from the particles, aided by chain transfer agents, the emulsifier dependence exponent for the number of polymer particles formed increases from 0.6 to 1.0 and the initiator dependence exponent decreases from 0.4 to 0. The effect of chain transfer agents on the nucleation and growth of polymer particles in the emulsion polymerization of styrene can be explained in terms of desorption of chain-transfered radicals from the polymer particles.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1279-1285 
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    Topics: Chemistry and Pharmacology
    Notes: The copolymerization of β-pinene with styrene oxide (SO) and β-pinene with N-vinylpyrrolidone (VP) was investigated by using SnCl4 in dichloromethane diluent at low temperature. Monomer reactivity ratios were evaluated for both copolymers at -80°C; these are r1(SO) = 2.979 and r2(β-pinene) = 0.002 and r1(VP) = 0.096 and r2(β-pinene) = 0.294.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1315-1329 
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    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: It is frequently observed that the gel effect in vinyl polymerizations decreases in intensity at about the 50-70% conversion level. This is apparent in both rate and molecular weight data. It is postulated that there should be a limitation on the decrease in the termination rate constant to explain this effect. As an extension of the general theory of chain length dependent termination behavior, a general treatment of the gel effect with a limiting value of the termination rate constant is presented. A specific model is proposed for this limited rate constant which is based on the simple consideration that as translational movement of macroradicals becomes increasingly difficult the contributions made by segmental motion derived solely from the propagation reaction will be the prevailing mechanism. The termination reaction changes from chain length dependent to chain length independent during this transition period.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1373-1387 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The wettability of poly(ethylene terephthalate) films is an important criterion for their industrial use. The attainment of that property is realized by treatment of the material under corona discharge. The purpose of this article is to describe the influence of the principal parameters of the discharge on the modification of the surface properties; the influence was measured by physicochemical methods (ESCA, contact angle). The results prove that the most important physical parameters of the discharge are the wire-cylinder distance, the current intensity, and the time of treatment. The analysis shows that the fixed species are oxygen and nitrogen in the form of carboxylic functions and amines or nitrogen oxides. In any case, the correlation between free surface energy and concentration of fixed chemical species shows that the surface properties depend on the chemical functions introduced into the material by the discharge.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1433-1443 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new catalyst system (Ph3SiCOPh-aluminum complex-alcohol) was investigated for photopolymerization of cyclohexene oxide. Polymer conversion and molecular weight increased with polymerization time. When a Ph3SiCOPh-Al (n-Praa)3-alcohol catalyst system was used the catalyst activity decreased, depending on the alcohol: i-PrOH 〉 n-PrOH 〉 i-BuOH 〉 MeOH 〉 t-BuOH 〉 H2O. When the Ph3SiCOPh-Al complex-i-PrOH catalyst system was used the catalyst activity decreased, depending on the ligand of the Al complex: ß-ketoester 〉 orthocarbonyl phenol 〉 ß-diketone. Benzophenone derivatives were effective for catalyst activation as a photosensitizer.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1489-1496 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The propagation and termination rate constants kp and kt for the radical polymerization of butyl acrylate initiated by biacetyl have been measured by using the rotating-sector method, in various solvents at 30°C. The value of kp and initiation rate Ri varied with solvents, while the value of kt did not change with solvents except for benzonitrile. The variation of kp with aromatic solvents has a trend against Hammett σp of the solvent substituents similar to that for methyl methacrylate or phenyl methacrylate except for the value in benzonitrile, when it is larger than the variation for methyl methacrylate or phenyl methacrylate. The larger variation of kp for butyl acrylate is compatible with the view that the origin of the solvent effect lies in complex formation between the propagating radical and aromatic solvent molecules. The exceptional decrease in kp and kt in benzonitrile is explained by a contraction of the poly(butyl acrylate) chain in the poor solvent.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1517-1532 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The influence of reaction conditions (solvent, Lewis acid, temperature) on the cationic copolymerization of isobutene and α-methylstyrene was investigated. The crude product consists of low molecular nonprecipitable oligomers, polyisobutene, and poly(isobutene-co-α-methylstyrene). The amount of poly(α-methylstyrene) formed under the reaction conditions used was negligible. The degree of charge separation in the propagating cationic intermediate determines the selectivity of the reaction; that is, incorporation of monomer units into the polymer, ratio of different product fractions, and microstructure. Molecular weight distribution, copolymerization parameters, and sequence-length distribution functions were determined. The softening range of the copolymers depended on their isobutene content but appeared to be constant up to 15% isobutene in copolymers. The degradation temperature of the copolymers was between 340 and 390°C.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1569-1579 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Formation of the HPAM-Tb3 complex in solution was observed in the intensification of Tb(III) fluorescence, viscosity, and light scattering. The interaction is dependent on the degree of hydrolysis of the copolymer and the pH of the solution. As the pH value increases, an intensification of the interaction and formation of a gel is observed. The latter was associated with the appearance of crosslinks in which terbium, or one of its hydrolysis products, works as a binding agent between chains. After drying, the characterization of the residues of the gels was effected by analytical determination (C, H, N, Cl, Tb), fluorescence, and infrared spectrophotometry. The analysis and fluorescence revealed the existence of particles of terbium hydroxide; the infrared spectrophotometry showed the binding of terbium (III) to carboxylate of the copolymer.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1609-1622 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(4′-methyl-4-vinyl-2,2′-bipyridine) has been prepared as have various copolymers with divinylbenzene. When polymerization is carried out in the presence of metal ions (Ni2+, Co2+, Cu2+) a metal-containing copolymer is obtained which, when the metal ion is removed with acid, retains some memory of the original chelating metal.
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1639-1647 
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    Topics: Chemistry and Pharmacology
    Notes: Copolymerization of N-oxyl biradical with α-chloro-p-xylylene was carried out by varying the feed ratio of α,α′-dichloro-p-xylene which was the precursor of α-chloro-p-xylylene. The structures of the obtained copolymers were determined spectroscopically. The results that the N-oxyl attacked the carbon-bearing chlorine atom of α-chloro-p-xylylene suggest a nucleophilic reactivity of N-oxyl radical. The copolymerization process was also discussed.
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 609-613 
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    Keywords: Physics ; Polymer and Materials Science
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    Topics: Chemistry and Pharmacology
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 633-634 
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    Keywords: Physics ; Polymer and Materials Science
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1819-1829 
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    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A detailed magic angle spinning 13C-NMR investigation of the intractable polymer prepared by plasma polymerization of toluene and isotopically labeled toluene led to a proposed model for the structure of the polymer and suggested some of the likely processes that occur in the gas phase leading to film formation. From the 13C spectra four resolved resonances permitted the determination of the contribution of nonprotonated and protonated unsaturated as well as methyl and other aliphatic carbons to the polymer structure. Specific 13C isotopic labeling of the methyl and phenyl C-1 toluene carbons in the injected liquid vapor allowed the destination of these carbons in the deposited polymer to be traced. The dominant structure is derived primarily from two precursors: benzyl radical and toluene itself. The 13C data further requires a net saturation of ca. 30% of the toluene double bonds and a net displacement of hydrogen by carbon on ca. 20% of the toluene ring carbons.
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  • 82
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Radiation-induced solid-state polymerizations of complexes of N-tert-butylacrylamide, N-tert-amylacrylamide, and N-tert-hexylacrylamide with zinc chloride and zinc bromide have been studied. An accelerating effect of temperature and an inhibiting effect of oxygen on the polymerization process were observed. The activation energies have been established. The influence of monomer structure as well as the halide used on the polymerization rate have been discussed and some regularities have been pointed out. The polymers obtained show good solubilities in common solvents, which proves that they are not crosslinked.
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  • 83
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1819-1831 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyesterification of diacid and diol in the presence of the foreign acid p-toluene sulfonic acid as catalyst was carried out under constant reaction temperatures of 140-166°C (rather than at the usual constant oil-bath temperature) and at molar ratios r of diol to diacid of 1.2-3.5. The experimental data obtained do not fit conventional rate equations as they appear in the literature. On the basis of ion pair formation, consideration of proton transfer from acid to alcohol, variation in dielectric constant of the reaction mixture as conversion increases, and inclusion of reverse reaction due to presence of unremoved water, we proposed a reaction mechanism and rate equations. The rate equation fitted our experimental data quite well. In addition the self-catalysis (absence of foreign acid) also showed promise, as confirmed by the experimental data measured under constant reaction temperatures, which appear in Part I.
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  • 84
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1875-1884 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The laser-initiated polymerization of charge-transfer monomer complexes was investigated with a pulsed nitrogen laser and an argon laser. Several donor-acceptor monomer charge-transfer systems were screened for polymerization in different solvents. Polymerization by laser initiation was achieved in two of these systems; that is, 2-vinylnaphthalene/fumaronitrile and 9-vinylanthracene/fumaronitrile. The best polymer yields were obtained with the 2-vinylnaphthalene/fumaronitrile system in sulfolane solvent. The influences on the polymer yield and composition of solvents, varying focal path length, glass conditioning, initiation sources, environment, and monomer feed ratios were evaluated. Infrared (IR) spectral studies, gel permeation chromatography (GPC), and chemical analyses were performed to characterize the polymer products arising from the polymerization of 2-vinylnaphthalene/fumaronitrile in sulfolane. The polymer contained a high percentage of sulfolane (ca. 1/3 mol fraction), presumably arising from solvent transfer to the growing polymer chains during the propagation phase of the polymerization.
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  • 85
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1943-1946 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 86
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1959-1963 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 87
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1993-2006 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Chain transfer constants to monomer have been measured by an emulsion copolymerization technique at 44°C. The monomer transfer constant (ratio of transfer to propagation rate constants) is 1.9 × 10-5 for styrene polymerization and 0.4 × 10-5 for the methyl methacrylate reaction. Cross-transfer reactions are important in this system; the sum of the cross-transfer constants is 5.8 × 10-5. Reactivity ratios measured in emulsion were r1 (styrene) = 0.44, r2 = 0.46. Those in bulk polymerizations were r1 = 0.45, r2 = 0.48. These sets of values are not significantly different. Monomer feed compcsition in the polymerizing particles is the same as in the monomer droplets in emulsion copolymerization, despite the higher water solubility of methyl methacrylate. The equilibrium monomer concentration in the particles in interval-2 emulsion polymerization was constant and independent of monomer feed composition for feeds containing 0.25-1.0 mole fraction styrene. Radical concentration is estimated to go through a minimum with increasing methyl methacrylate content in the feed. Rates of copolymerization can be calculated a priori when the concentrations of monomers in the polymer particles are known.
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  • 88
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    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2043-2051 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polytrifluoromethylacetylene (PTFMA) was synthesized from trifluoromethylacetylene (TFMA) using a PdCl2/DMF catalyst solution or the anionic initiator n-butyl lithium. Although PdCl2 proved to be an effective catalyst for the polymerization of TFMA, long reaction times and poor yields made characterization of the resultant polymer difficult. The use of n-butyl lithium, on the other hand, resulted in high yields of PTFMA in relatively short reaction times. The results of thermal analysis and the effects of n- and p-type doping on the electrical conductivity of the polymer are discussed.
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  • 89
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 803-810 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The free radical polymerization of acrylonitrile (AN) initiated by Cu(II) 4-anilino 2-one [Cu(II) ANIPO] Cu(II), 4-p-toluedeno 3-pentene 2-one [Cu(II) TPO], and Cu(II) 4-p-nitroanilino 3-pentene 2-one [Cu(II) NAPO] was studied in benzene at 50 and 60°C and in carbon tetrachloride (CCl4), dimethyl sulfoxide (DMSO), and methanol (MeOH) at 60°C. Although the polymerization proceeded in a heterogeneous phase, it followed the kinetics of a homogeneous process. The monomer exponents were ≥2 at two different temperatures and in different solvents. The square-root dependence of Rp on initiator concentration and higher monomer exponents accounted for a 1:2 complex formation between the chelate and monomer. The complex formation was shown by ultraviolet (UV) study. The activation energies, kinetics, and chain transfer constants were also evaluated.
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  • 90
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N-Methylacrylamide (NMAAm) was polymerized quantitatively by using di-tert-butyl peroxide as photosensitizer to be, for the most part, incorporated in living poly(NMAAm) radical. The living polymer radical reacted effectively with acrylate monomers to yield block copolymer. Longer alkyl chain of the acrylate monomer caused a decrease in the conversion of the second monomer. Methacrylate monomers, such as methyl methacrylate and cyclohexyl methacrylate, showed relatively low reactivities in comparison with acrylates. Styrene exhibited a much lower conversion. The resulting block copolymers showed different thermochromic behaviors in methyl benzoate from that of poly(NMAAm). This is explained on the basis of the difference between refractive indexes of the block copolymers and poly(NMAAm).
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  • 91
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 865-881 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyimide films based on either 3, 3′, 4, 4′-benzophenone tetracarboxylic acid dianhydride or pyromellitic dianhydride with 4,4′-oxydianiline have been doped with copper(I) and copper(II) complexes. High-quality, flexible, glass-cast films have been obtained which exhibit increased softening temperatures and lower polymer decomposition temperatures. The atmosphere and glass sides of the films are quite different. The copper(I) dopant is oxidized on the air side of the film, while the glass side contains predominantly copper (I). In the copper(II) case most of the copper appears on the air side as a silvery substance in the Cu(II) state. Chemical as well as ion etching can remove this material. Electrical resistivity of the copper(II)-doped films is decreased by three to five orders of magnitude relative to the polymer alone.
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  • 92
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 883-890 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of two phenylated bifunctional monomers, dimethyl 4-(4-(p-aminophenoxy)phenyl)-3,5,6-triphenylphthalate and dimethyl 4-(4-(4-(p-aminophenoxy)phenoxy)phenyl)-3,5,6-triphenylphthlate, was accomplished. Polymerization in solution or by a bulk polymerization procedure yielded a series of low molecular weight phenylated polyimides. The polymers were soluble in chlorinated hydrocarbons and exhibited thermal stabilities comparable to other polyimide systems.
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  • 93
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 937-941 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The structural changes in the potassium graphitide KC24 in its interaction with ∊-caprolactone, γ-butyrolactone and pivalolactone are examined by profilometric measurement and electron scanning microscopy. The interaction of KC24 with a nonpolymerizable lactone-γ-butyrolactone proceeds without delamination of the graphitide. The polymerization of ∊-caprolactone and pivalactone in the interlayer spaces of KC24 leads to destruction of the initiators structure. An increase in the temperature and monomer concentration enhances the delamination of the graphitide.
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  • 94
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A procedure was developed by which polymer colloids can be prepared by polymerizing aerosol droplets of monomers with an initiator in the vapor state. This work describes the formation of poly(p-tertiarybutylstyrene) particles by exposing the corresponding monomer droplets to trifluoromethanesulfonic acid. It was found that the monomer-to-initiator mass ratio is the critical factor in determining the uniformity and morphology of the particles. Under ideal conditions spheres of narrow size distribution are obtained. Otherwise porous particles or soft particles with whiskers may develop. The aerosol was prepared in a falling film generator, but other procedures for producing monomer droplets may be used.
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  • 95
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 999-1012 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polycondensation of the diacid chloride of 2-(3-carboxy vinyl)phenyl-1,3-dioxoisoindoline-5-carboxylic acid with m-phenylenediamine and the diacid chloride of 2-(4-carboxy phenyl)-1,3-dioxoisoindoline-5-carboxylic acid with 1,5-bis(3-aminophenyl)1,4-pentadien-3-one was carried out in polar solvents to produce new unsaturated polyamide-imides. The solution and the thermal, electrical, and a few other properties of the polymers were studies. The polymers were soluble in highly polar solvents. The solubility parameter of the polymers was calculated from the Small's group contribution. The polymers were fairly thermostable and underwent crosslinking creaction when heated, preferably in the presence of a suitable catalyst. The crosslinked polymers were in soluble even in highly polar solvents and possessed higher thermal stability. The swelling behavior of the polymers was studied and the molecular weight between two consecutive crosslinks was determined. X-ray diffraction and the dielectric properties of the polymers and their crosslinked products were also studied.
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  • 96
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1013-1024 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Crosslinked polystyrene particles were prepared by Friedel-Crafts suspension crosslinking of polystyrene using 2,4-dichloromethyl-2,5-dimethyl benzene as crosslinking agent. The polymer was dissolved in nitrobenzene and reaction occurred in a 70 wt % aqueous solution of ZnCl2 with poly(vinyl alcohol) as a suspending agent. The spherical particles produced were swollen in toluene, chloroform, and tetrahydrofuran to determine their equilbrium polystyrene volume fraction. Analysis of the crosslinked macromolecular structure gave values of number-average molecular weight between crosslinks of M̄c = 900-5900 increasing as the nominal crosslinking ratio X decreased from 0.75 to 0.0625 mol of crosslinking agent per mole of polystyrene repeating unit. Porosimetric analysis contributed to the understanding of the importance of the pore structure for swelling behavior.
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  • 97
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An efficient kinetic method of reactivity ratio measurement for binary copolymerization of gaseous monomers4 that does not require the measurement of copolymer composition and can be applied to the data obtained in a single copolymerization run was modified and applied to olefin copolymerization with heterogeneous Ziegler-Natta catalysts. Estimated r1 and r2 values for pairs like ethylene-propylene and propylene-1-butene agree favorably with published data.
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  • 98
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1097-1110 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new redox couple based on the copper-catalyzed reduction of diaryliodonium salts with benzoins has been used to initiate cationic polymerizations of cyclic ethers and esters. A proposed mechanism for initiation by this redox couple is based on its stoichiometry and on the nature of the products. It was concluded that initiation of polymerization occurs both by direct arylation of the monomer and by protonation by strong Brønsted acids. The polymerization of several typical cationically polymerizable monomers using this new redox initiator were studied.
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  • 99
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 1125-1137 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A regenerable dihydronicotinamide immobilized on a macroreticular polystyrene carrier was developed and used in an aqueous medium for the reduction of trifluoroacetophenone to the corresponding alcohol. It was shown that the second-order rate constant for the polymer-bound reagent is significantly lower than that of the low-molecular-weight analog 1-benzyldihydronicotinamide. The observed reaction rate, however, was of the same order of magnitude as that due to enrichment of substrate in the polymeric pores. It was possible to depress the undesired side reactions to 10-15% per reaction cycle, thereby allowing reutilization of the functionalized polymer.
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  • 100
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    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2451-2461 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The 337.1-nm emission of a pulsed nitrogen laser was shown to initiate the crosslinking polymerization of epoxy-acrylate photoresists effectively. We evaluated the extent of curing from the amount of insoluble polymer formed and by the decrease in infrared (IR) absorption of the reactive double bond at 810 cm-1. With the large power density available in the laser pulse (0.5 MW cm-2) rates of polymerization as high as 108 mol L-1 s-1 were observed in the presence of air. Quantum yield measurements indicated that each photon absorbed can create as many as 450 crosslinks; the kinetic chain length was calculated as ca. 4000 double bonds polymerized per initiating radical. During the induction period due to oxygen inhibition each photoinitiator radical consumed 1 O2 molecule. The influence of the monomer and photoinitiator used on the sensitivity of the resin was examined; the best performing formulation contained the epoxy-acrylate oligomer, pentaerythritol triacrylate, as monomer and 2,2 dimethoxy-2-phenyl-acetophenone as photoiniatior. All the formulations studied can be cured by a single 500-kW laser pulse of 8 ns duration, provided that the irradiation is carried out in an inert atmosphere or with a focused laser beam.
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