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  • 1
    ISSN: 1042-7147
    Keywords: Solid polymer electrolyte ; Ionic conductivity ; Spiropyran derivative ; Merocyanine form ; Photoisomerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Photoresponse in ionic conductivity has been realized in the solid polymer electrolytes, consisting of poly[(ω-hydroxy) oligo(oxyethylene) methacrylate] [P(MEO)OH] or poly[(MEO)OH-co-butyl methacrylate] (PBMA), spiropyran derivative (SP) and LiClO4. SP showed reversible isomerization upon photoirradiation in these films. The ionic conductivity in these films decreased upon ultraviolet light (UV) irradiation and subsequently increased upon visible light (Vis) irradiation. The interaction between photoisomerized merocyanine form (PMC form) and the hydroxyl group on the polymer side chain was confirmed by an IR shift assignable to O—H stretching vibration. From DSC thermograms, the change of ionic conductivity was revealed to be considerably affected by this interaction and attributed to reversible photoisomerization of SP. Reversibility of ionic conductivity was improved in copolymer P[(MEO)OH-co-BMA] in comparison with that in P(MEO)OH.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 86 (1965), S. 200-216 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Bei der kationischen Polymerisation substituierter Styrole mit Jod als Initiator steigt die Geschwindigkeitskonstante der Wachstumsreaktion mit der Polarität der verwendeten Lösungsmittel an. Bei der Copolymerisation wird mit zunehmender Polarität des Reaktionsmediums dasjenige Monomere bevorzugt eingebaut, das die geringere Solvatationskraft aufweist. Zur Erklärung dieser Befunde wird angenommen, daß die beim Angriff eines Monomermoleküls erfolgende Abdissoziation des Gegenanions vom Ionenpaar des wachsenden Kettenendes der geschwindigkeitsbestimmende Schritt für die Polymerisation ist.
    Notes: The solvent effect on cationic polymerization of styrene derivatives with iodine as the initiator was studied. It was proved that the propagation constant increased remarkably with the polarity of solvent. In the copolymerization the content of the monomer with less solvating power increased in copolymer as the polarity of the medium increased. It was assumed that the process of the dissociation of the gegen anion of the attacking monomer is predominantly rate-determining in propagation reaction.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 11 (1973), S. 1167-1176 
    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 4,4-diphenyl-Δ2-1,2,3-triazolin-5-one (I) was reinvestigated and shown to yield poly-α,α-diphenylglycine (III) instead of the previously reported 3,3,6,6-tetraphenylpiperazine-2,5-dione (II). Differentiation between the two structures was made by molecular weight determinations and spectroscopic analyses. The infrared spectra were studied in detail and compared with model compounds. They showed that the absorption peak at 1470 cm-1 must be attributed to the trans-amide II absorption of the polymer. Furthermore, the polymers were found to contain terminal CONH2 as well as triazolinone or ether functions (from alcohol). Fractionation was performed in three solvents based on solubility differences: dichloroethane (or chloroform), methanol, and n-hexane. All the fractions were characterized by physical methods. A mechanistic investigation revealed that the polymerization process cannot be rationalized by a radical or cationic mechanism, but is compatible with a molecular mechanism involving triazolinone functions at the growing chain ends.
    Additional Material: 2 Ill.
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  • 4
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 11 (1973), S. 1177-1183 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 4,4-Diphenyl-Δ2-1,2,3-triazolin-5-one (I) was found to undergo a cationic polymerization under the influence of boron trifluoride etherate in an anhydrous solvent. The poly-α,α-diphenylglycine (III) thus formed contained a larger amount of oligomers than the polymer obtained by thermal decomposition as described in the preceding paper. The molecular weight distribution was further shown to depend on the monomer and catalyst concentration and on the nature of the solvent. A mechanistic rationalization is proposed, involving propagating triazolinium ion pairs (VII) which are not interrupted by chain transfer or termination in the absence of water or alcohol. In the presence of water or alcohol, no polymerization occurred, but the normal acid-catalyzed decomposition products (IV and V) were then obtained. 1-Methyl-4,4-diphenyl-Δ2-1,2,3-triazolin-5-one (VIII) was also treated with BF3 · OEt2 in a dry solvent at room temperature and furnished 1-methyl-3-phenyl-indolin-2-one (XII) instead of a polyamide. This reaction constitutes a new method for the synthesis of these heterocycles.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
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