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  • 1975-1979  (4)
  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 79 (1979), S. 163-176 
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: A series of styrene and acenaphthylene copolymers were prepared by thermal polymerization at 100°C. Films of copolymers with various contents of acenaphthylene were exposed to light in an apparatus (Xenotest) under the atmosphere of normal air and in some cases under nitrogen. The degradation of copolymers was followed by measurements of solution viscosity. Copolymers with small contents of acenaphthylene (4,2 mol-%) show slower degradation than polystyrene up to exposure times of about 80 h, but then a stronger degradation takes place with increased content of acenaphthylene. In the presence of oxygen the formation of benzene-insoluble particles besides degradation was observed. The amount of these “benzene-insoluble” particles, which have a specific absorption in the infrared at 1730 cm -1, depends upon the exposure time and the content of acenaphthylene. No such benzene-insoluble products were found if the films were exposed to light in the same apparatus under nitrogen atmosphere.
    Notes: Styrol wurde mit Acenaphthylen thermisch bei 100°C copolymerisiert. Folien der Copolymeren mit steigendem Acenaphthylengehalt wurden verschieden lange in einem Xenotest®-Gerät in Luft und teilweise in Stickstoffatmosphäre bestrahlt. Zur Verfolgung des Abbaus wurde die Lösungsviskosität gemessen. Bei geringen Acenaphthylengehalten (4,2 mol-%) ist der Abbau bis zu Bestrahlungszeiten von ca. 80 h langsamer als der des Polystyrols, erst dann findet stärkerer Abbau mit wachsendem Acenaphthylengehalt statt. Beim Abbau entstehen in Gegenwart von Sauerstoff Produkte, deren IR-Spektren bei 1730 cm-1 eine charakteristische Bande aufweisen und die in Benzol unlöslich sind. Ihre Masse ist von der Bestrahlungszeit und vom Acenaphthylengehalt im Copolymeren abhängig. Beim Bestrahlen unter Stickstoffatmosphäre werden solche unlöslichen Produkte nicht gebildet.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 83 (1979), S. 161-169 
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Films of copolymers of styrene and acenaphthylene were exposed to light in an apparatus (Xenotest®) for different periods. While the transmission of samples with lower contents of acenaphthylene (5 mol-%) is changing only a little, it strongly decreases in case of copolymers with higher content of acenaphthylene already with short exposure time. The tensile strength increases under an exposure time of about 7 hours and is higher also at increased content of acenaphthylene until to 72 hours, respectively, comparable with that of homopolystyrene. Under the irradiation the molecular-weight distribution will be expanded and the portion of low molecular polymers is increased.
    Notes: Folien von Copolymeren aus Styrol und Acenaphthylen werden verschieden lange in einem Xenotest®-Gerät bestrahlt. Während sich bei Proben mit neidrigem Acetnaphthylengehalt (bis 5 mol-%) die Transmission durch die Bestrahlung nur wenig ändert, nimmt sie bei Copolymeren mit höherem Acenaphthylengehalt schon bei kurzen Bestrahlungszeiten stark ab. Die Zugfestigkeit steigt bis zu Bestrahlungszeiten von ca. 7 Stunden an und ist bis zu 72 Stunden auch bei steigendem Acenaphthylengehalt höher bzw. vergleichbar mit der des reinen Polystyrols. Durch die Bestrahlung wird die Molmassenverteilung breiter, und der Anteil an niedermolekularen Polymeren nimmt zu.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Experiments regarding the anionic polymerization of acenaphthylene with different initiators (lithiumnaphthalene complex, 1,2-diphenylethylenedilithium, 1,1,4,4-tetraphenyltetramethylenedilithium and butyllithium) and solvents (tetrahydrofuran and benzene) show that only short chain (P̄ ≈ 20) and coloured polymers with broad molecular weight distribution are obtained, because of chain transfer reactions to the monomer. A mechanism of this polymerization is proposed. By radical polymerization short chain polyacenaphthylene with definite end groups can be obtained.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 178 (1977), S. 2507-2514 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The preparation and characterization (analyses of IR and mass spectra) of 5-methyl-5-hexen-2,4-dione (1) and its polymerization and copolymerization with styrene are described. Poly(1) and copolymers from 1 and styrene give metal chelates in solution and on metal surfaces. Copolymers of 1 and styrene increase the adhesion and the resistance against corrosion of varnishes for metals on the basis of melamine.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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