ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
Collection
Publisher
Years
  • 1
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 13 (1975), S. 1017-1028 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A soluble and self-crosslinkable linear copolymer with pendant epoxy and pyridyl groups was obtained from glycidyl methacrylate (M1) and 2-vinylpyridine (M2) or 2-vinyl-5-ethylpyridine (M2) by the action of azobisisobutyronitrile. The monomer reactivity ratios were determined in tetrahydrofuran at 60°C: r1 = 0.510, r2 = 0.620 with 2-vinylpyridine and r1 = 0.57, r2 = 0.62 with 2-vinyl-5-ethylpyridine. These were consistent with the calculated values with the reported Q and e values for these monomers. The intrinsic viscosities of the copolymers with 2-vinylpyridine and with 2-vinyl-5-ethylpyridine were found to be 0.17-0.19 and 0.26-0.38, respectively, in tetrahydrofuran at 30°C; they were independent of the copolymer composition. The copolymers were amorphous, had no clear melting points, and became insoluble crosslinked polymers under heating without further addition of any curing agents.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 0360-6384
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    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: Ein neuer thermotroper flüssig-kristalliner Vinyläther, 4-(2-Vinyloxyäthoxy)benzoesäure (1a), wurde durch Hydrolyse des entsprechenden Methylesters 1b erhalten. Seine radikalische Polymerisation in Substanz wurde bei 130-195°C in fester, mesomorpher und isotrop-flüssiger Phase mit 2,2′-Azoisobutyronitril durchgeführt, um den Effekt der Monomerordnung auf die Polymerisationsgeschwindigkeit und die Eigenschaften des Polymers zu untersuchen. Das Auftreten mesomorpher Phasen scheint nicht von einem besonderen Effekt auf die Polymerisationsgeschwindigkeit und den Staudinger-Index begleitet zu sein. Die Geschwindigkeit nahm mit steigender Temperatur zu, d.h. mit abnehmender Ordnung oder erhöhter Beweglichkeit des Monomers. In N,N-Dimethylformamid beträgt der Staudinger-Index bei 30°C 0,06-0,10 dl g-1. Hochkristalline Polymere wurden in der festen und mesomorphen Phase erhalten. Das in der isotrop-flüssigen Phase gebildete Polymer war dagegen weniger kristallin.
    Notes: A new thermotropic liquid crystalline vinyl ether, 4-(2-vinyloxyethoxy)benzoic acid (1a), was obtained by hydrolysis of the corresponding methyl ester 1b. The radical bulk polymerization of this acid was carried out at 130-195°C in the solid, the mesomorphic, and the isotropic liquid phases with 2,2′-azoisobutyronitrile to study the effect of monomer ordering on polymerization rate and polymer properties. No significant effect on the rate of polymerization and the intrinsic viscosity of the products appeared to be associated with the existence of the mesomorphic phases. The rate increased with increasing temperature, i.e., decreasing ordering or enhanced mobility of the monomer. The intrinsic viscosity was 0,06-0,10 dl g-1 in N,N-dimethylformamide at 30°C. High crystalline polymers were obtained in the solid and the mesomorphic phases, whereas the polymer formed in the isotropic liquid phase was a less crystalline solid.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    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: Die durch AIBN initiierte Copolymerisation von 2,3-Epoxy-1-propylmethacrylat (1) (M1) und 5-Äthyl-2-vinylpyridine (1) (M2) wurde in THF bei 60°C unter hohem Druck (bis 15 kbar) untersucht. Unter Druck wurden lösliche, lineare Polymere erhalten, die seitenständige Epoxy- und Pyridylgruppen enthalten und die als selbsthärtende Harze verwendet werden können. Die Copolymerisationsparameter r1 und r2 nehmen mit steigendem Druck zu (angegeben ist r1, r2 sowie der Druck in kbar): 0,60, 0,64 bei 2 kbar; 0,64, 0,66 bei 4 kbar; 0,72, 0,69 bei 7 kbar; 0,78, 0,72 bei 10 kbar; 0,87, 0,76 bei 13 kbar; 0,91,0,80 bei 15 kbar. Es ist daher wahrscheinlich, daß das Aktivierungsvolumen des Kettenwachstums, Δ*p, für beide Kettenwachstumsschritte unterschiedlich ist. Die Viskositätszahlen der Copolymeren in THF bei 30°C liegen zwischen 0,26 und 1,35 ; wobei der Wert vom Polymerisationsdruck und der Copolymerenzusammensetzung abhängt. Die Copolymeren sind amorph, besitzen keinen klaren Schmelzpunkt und gehen beim weiteren Erhitzen ohne Zusati: von Härtern in vernetzte Polymere über.
    Notes: 2,2′-Azoisobutyronitrile-initiated copolymerization of 2,3-epoxy-1-propyl methacrylate (1) (M1) with 5-ethyl-2-vinyl-pyridine (2) (M2) was studied in tetrahydrofuran at 60°C under high pressure up to 15 kbar. Under pressure, soluble linear polymers with pendant epoxy and pyridyl groups were obtained and can be used as self-curable resins. The monomer reactivity ratios, r1 and r2, became larger with increasing pressure (r1, r2, and pressure given): 0,60, 0,64 at 2 kbar; 0,64, 0,66 at 4 kbar; 0,72, 0,69 at 7 kbar; 0,78, 0,72 at 10 kbar; 0,87, 0,76 at 13 kbar; 0,91, 0,80 at 15 kbar. Therefore, the change of activation volume of the chain propagation, ΔV*p, may vary from one type of propagation step to another. The intrinsic viscosities of the copolymers were found in tetrahydrofuran at 30°C to be 0,26 to 1,35 and to be dependent upon the copolymer composition and the pressure. These copolymers were amorphous, had no clear melting points and became insoluble crosslinked polymers under heating without further addition of any curing agents.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...