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  • 1
    Electronic Resource
    Electronic Resource
    Mechanical relaxations in polyamides (1971)
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-2: Polymer Physics 9 (1971), S. 867-886 
    Details
    ISSN: 0449-2978
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Dynamic mechanical measurements were carried out as a function of temperature (-100 to + 180°C) and frequency (3.5 to 110 cps) for a series of aliphatic terpolyamides, nylon 6 and nylon 12. Effect of crosslinking with toluene diisocyanate, of absorbed water, and of frequency are used to estimate the statistical segment length associated with the α′ relaxation. The effects of variations in the aliphatic chain length in the repeating unit on the temperature of the α′ relaxation are examined by means of copolymer rules with a view to explaining the reported insensitivity of the glass transition temperature of these polymers to changes in (CH2)/(amide) group ratio. From the estimated length of the segmental motion associated with the α′ relaxation it is inferred that in a series of polyamides of the type nylon X or nylon X,Y (where X or Y = 3, 4, 5, 6, etc.) there should be a relatively small change in the temperature of the α′ transition for those polyamides having X or Y less than about 45. Experiments which are intended to establish the position of the crystalline α-γ transition are discussed.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1971.160090508
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  • 2
    Electronic Resource
    Electronic Resource
    Selective initiation of nonconjugated dienes containing electron donor-electron aceptor systems. I. Synthesis of vinyl ether-β-nitrostyrene monomers (1978)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 16 (1978), S. 1343-1357 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The objectives of this work were to synthesize, characterize, and conduct a polymerization study on a set of ideal crosslinking monomers. The monomers studied are the three isomers of (2-vinyl-oxyethoxy)-β-nitrostyrene. Such monomers contain both the electron-donating vinyl ether moiety and the electron-accepting β-nitrostyrene moiety. A study of the spectral properties of these monomers was carried out in an effort to determine whether there was a contribution to the structure through an intramolecular interaction of the nature of a charge-transfer complex. Such studies have led to little or no support for such an interaction. As model compounds for comparison of spectral properties, the monomer series, o-, m-, and p-(2-ethoxyethoxy)-β-nitrostyrenes were synthesized and characterized as above. A comparison of the spectral and physical properties of these two series of compounds show that there are significant differences suggestive of the interactions proposed. However, since these discrepancies are small in most cases, it is not possible at present to correlate them specifically with the postulated intramolecular interactions.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1978.170160615
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  • 3
    Electronic Resource
    Electronic Resource
    Selective initiation of nonconjugated dienes containing electron donor-electron acceptor systems. II. Polymerization studies of vinyl ether-β-nitrostyrenes (1978)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 16 (1978), S. 1359-1365 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The monomer series, o-, m-, and p-(2-vinyloxyethoxy)-β-nitrostyrenes, was studied. All three monomers were selectively polymerized through the electron-donating vinyloxy group via cationic initiation. The linear polymers from the meta and para isomers containing the electron-accepting nitrovinyl group were readily crosslinked via anionic initiation. The polymer derived from the ortho isomer was not crosslinked by this mechanism, an observation in accord with results previously reported from these laboratories in which it was shown that all o-substituted-β-nitrostyrenes having ortho substituents larger than fluorine exhibited a sterically inhibited propagation step. The meta and para isomers of this series were selectively polymerized through the electron-accepting nitrovinyl group via anionic initiation. Because of the fact that the resulting polymers were soluble only in highly polar solvents, subsequent crosslinking of these polymers via cationic initiation could not be accomplished. However, these polymers showed strong tendencies to undergo crosslinking upon long exposure to air. Because of the sterically induced ortho effect referred to above, no significant polymerization occurred in the case of the ortho isomer of this series via anionic initiation. However, it was shown in this case that initiation via the anion was rapid, and that the slow step was propagation.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1978.170160616
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  • 4
    Electronic Resource
    Electronic Resource
    Selective initiation of nonconjugated dienes containing electron donor-electron acceptor systems. III. Synthesis of vinyl ether-styrene monomers (1978)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 16 (1978), S. 1367-1373 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In a continuation of our studies on nonconjugated dienes containing electron donor-electron acceptor systems which may function as model crosslinking monomers, we here report the synthesis of the series, 2-, 3-, and 4-(2-vinyloxyethoxy)styrenes. The dipole moments μ, infrared and ultraviolet absorption properties, refractive indices nD30, molar refractions (MRD), and optical exaltations of the compounds were determined. In order to establish whether any intramolecular electronic interactions, e.g., intramolecular charge-transfer complexes, contribute to the structure and properties of these compounds, 2- and 4-(2-ethoxyethoxy)styrenes were also prepared, and their properties compared with those of the vinyloxy series. While there are differences in certain of the properties of these two groups of monomers, these differences are not sufficiently large to permit definite correlations with the proposed interactions.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1978.170160617
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  • 5
    Electronic Resource
    Electronic Resource
    Selective initiation of nonconjugated dienes containing electron donor-electron acceptor systems. IV. Polymerization of vinyl ether-styrene monomers (1978)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 16 (1978), S. 1375-1389 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Three isomeric nonconjugated dienes, o-, m- and p-(2-vinyloxyethoxy)styrenes, were selectively polymerized by anionic or radical initiators through the styryl double bond while leaving the vinyl ether moiety intact. The anionic-initiated polymeric products are of high molecular weight and narrow molecular weight distribution as characterized by membrane osmometry and gel-permeation chromatography, respectively. These polymers were subsequently crosslinked by cationic initiators via the vinyl ether moiety on the polymer side chains. Acid-catalyzed hydrolysis of the poly(2-vinyloxyethoxy)styrenes yielded their respective hydroxy-containing polymers, polyvinylphenoxyethanols. The latter were physically and spectroscopically identical to authentic samples prepared by radical polymerization of the corresponding vinylphenoxyethanols, which, in turn, were synthesized by hydrolysis of the (2-vinyloxyethoxy)styrenes. The polyvinylphenoxyethanols were shown to undergo many chemical transformations, such as esterification with 3,5-dinitrobenzoyl chloride, cyanoethylation, and urethane formation.
    Additional Material: 7 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1978.170160618
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  • 6
    Electronic Resource
    Electronic Resource
    Synthesis and properties of alternating copolymers of potential antitumor activity containing 5-fluorouracil (1979)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 17 (1979), S. 351-363 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: “Pyran” copolymer, the 2:1 regularly alternating cyclocopolymer (DVE - MA) of maleic anhydride (MA) and divinyl ether (DVE), first discovered in 1951, has been investigated extensively, both from the standpoint of its chemical structure and its biological activity. Although certain aspects of its structure remain to be determined, it has been shown to possess a wide spectrum of biological activity. It possesses antitumor activity and has been investigated clinically. During the clinical investigation, it was found to be an interferon inducer. Interferon is a protein which appears to be the body's first line of defense against viral infection. DVE - MA also possesses antiviral, antibacterial, antifungal, antiarthritic, and anticoagulant properties, activates macrophages, inhibits reverse transcriptase, and is capable of elimination of Pu. During the course of investigations in these laboratories, many structural modifications of DVE - MA have been made. Many of these modifications also possess considerable antitumor activity and interferon-induction capability. Perhaps the most interesting structural modification has been the incorporation of 5-fluorouracil (5-FU) into the polymer (NSC 255083). This polymer has shown (T/C)% [= ratio of test (T) to control (C) survival times] = 189 for dose by intraperitoneal injection of 200 mg/kg animal weight in CD2F1 mice (6/6 survivors after fifth day) against P388 lymphocytic leukemia. This article describes the synthesis of both the monomer and copolymer, and a study of the hydrolytic rate of release of 5-FU from the polymer.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1979.170170205
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  • 7
    Electronic Resource
    Electronic Resource
    Structure study of the furan-maleic anhydride copolymer (1981)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 19 (1981), S. 1175-1196 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A structural study of furan-maleic anhydride copolymer (F-MAH) was undertaken to confirm its alternating nature and to determine its microstructure. The spectral properties of a model compound representing the alternating repeat unit, 2-(2-tetrahydrofuranyl)succinic anhydride, were compared with those of F-MAH. Their infrared (IR), 1H, and 13C nuclear magnetic resonance (NMR) spectra (after compensating for the absence of the olefinic double bond) were in good agreement with those of the copolymer. Furthermore, the observed splitting in the 1H- and 13C-NMR spectra of F-MAH were assigned to cis-trans linkages on both the F and MAH units, with cis linkage being favored on both units, especially the former. The structure of 2,5-dimethylfuran (DMeF)-MAH copolymer is similar to that of F-MAH copolymer, except that the preference of cis linkages is less pronounced. The structure of 2-methylfuran (MF)-MAH copolymer is a complex structure with numerous 2,3-furandiyl units. A mechanistic study was undertaken to elucidate the roles of F-MAH Diels-Alder adduct, and the charge-transfer (CT) complex in the radical initiated copolymerization. The adduct reverted substantially to monomers under the reaction conditions; but, the amount of adduct remaining at equilibrium was quite appreciable; therefore, its participation could be ruled out on this basis alone. However, on polymerizing the adduct in the presence of F-d4, the latter was incorporated into the copolymer to an extent indicative of free monomer exchange. Therefore, the adduct cannot be directly involved in the polymerization.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1981.170190514
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  • 8
    Electronic Resource
    Electronic Resource
    Low-temperature modification of dienic polymers via the “Ene” reaction with 4-substituted-1,2,4-triazoline-3,5-diones (1979)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 17 (1979), S. 1117-1128 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 4-Substituted-1,2,4-triazoline-3,5-diones have been used to synthesize a series of new polydienes by the “ene” reaction at ambient temperatures. The extent of chemical conversion can be varied widely and up to 93% of the diene-repeating units of the parent polymer chain undergo reaction. Yields of the new polymers based on the reactant range from 90 to 95% at room temperature; their physical properties range from secondary crosslinking effects or elasticity at low degrees of conversion to rigid, amorphous polymers with high softening points at high degrees of conversion. The new polymers show a predictable correlation between the extent of conversion and the softening point. A similar correlation exists between the polarity of the new polymers and the extent of conversion. Polydienes with conversions to the extent of 45% or greater are soluble in aqueous solutions of sodium hydroxide and those with conversions of 60% or greater are soluble in aqueous sodium bicarbonate. Thus, in general, the new polymers (1) have higher Tg, (2) become increasingly polar, hence are soluble in polar solvents, and (3) possess a reasonably acidic proton, hence form salts. Bistriazolinediones result in room temperature crosslinking. A kinetic study with model compounds suggests that the rate of the reaction can be varied, depending on the electronic nature of the 4-substituent.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1979.170170416
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  • 9
    Electronic Resource
    Electronic Resource
    Anionic-initiated polymerization of β-nitrostyrenes (1978)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 16 (1978), S. 937-959 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: β-Nitrostyrene and many of its derivatives have been shown to yield high polymers via anionic initiation with alkoxide ions in protic solvents, e.g., alcohols. A study was conducted to determine the effect of certain substituents on the polymerization characteristics of representative monomers of this series and the properties of their polymers. A kinetic study was conducted and the relative rates of propagation were unexpectedly found to correlate well with brown's σ+ values. The rates of initiation of two representative monomers, β-nitrostyrene and p-methoxy-β-nitrostyrene, with sodium ethoxide were found to be 3.51 and 2.86 liter/mole sec, respectively. The rate of chain transfer in ethanol was studied qualitatively by using gel-permeation chromatography (GPC) to obtain molecular weight distribution (MWD) curves. The low values of the Mw/Mn ratios indicated little chain transfer in the protic solvent.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1978.170160507
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  • 10
    Electronic Resource
    Electronic Resource
    A study of the ring size in the copolymer of divinyl ether and maleic anhydride by H-NMR spectroscopy (1979)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 17 (1979), S. 859-876 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The well-known alternating 1:2 cyclocopolymer of divinyl ether (DVE) and maleic anhydride (MA) possesses a wide spectrum of biological activities, including antitumor. Recent research on the structure of a variety of cyclopolymers has raised a question about the ring size of this cyclocopolymer. In this article we report on an extensive spectroscopic study of its structure. By use of deuterated monomers the H-NMR peaks at δ 2.31, 3.47, 4.06, and 4.49 ppm with an area ratio of 2:1:1:1 were assigned to the hydrogens of methylenes, methines on the backbone anhydride unit, methines on the ring anhydride unit, and methines adjacent to oxygen on the cyclic ether ring, respectively. By examination of the possible isomeric structures of the bicyclic ring, the splitting of each peak group was further assigned for cis and trans disubstitutions on the anhydride unit. The splitting pattern from the 300-MHz NMR spectrum of the DVE-2,3-dideuteriomaleic anhydride (DMA) copolymer confirmed the unsymmetrical ring structure. 13C-NMR spectra were consistent with the conclusion from the H-NMR spectra. A chair-form, six-membered ring with predominantly trans geometry in the anhydride ring was assigned to the structure of DVE-MA copolymer. On the basis of little or no change in the 13C-NMR spectra of the copolymers prepared at different temperatures it was concluded that there was no significant change in structure with temperature. This led to the assignment of the energetically favored, six-membered ring structure to the copolymer prepared under these conditions. A mechanism for cyclocopolymerization, based on the HOMO-LUMO interaction of the comonomers and the intramolecular radical addition on the preoriented double bond, was proposed. This mechanism leads to the formation of the six-membered ring structure of the copolymer as the only product. A 13C-NMR study of the structure of the copolymer prepared in chloroform by Kunitake and Tsukino is being published as a companion article.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1979.170170324
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