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Liquid crystallinity of main chain polyurethanes based on 4,4′-azobenzenediisocyanate

✍ Scribed by G. Kossmehl; B. Hirsch

Publisher
John Wiley and Sons
Year
1990
Tongue
English
Weight
384 KB
Volume
41
Category
Article
ISSN
0323-7648

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✦ Synopsis

Polyurethanes were synthesized from 4,4'-azobenzenediisocyanatc with mono-, di-, tri-and tetraethylene glycol and their thermal properties were investigated. One of the resulting polymers, poly(oxycarbonylimino-4,4'-azobenzene-diyliminocarbonyloxyethyleneoxyethyleneoxyeth~lene) shows a liquid crystalline phase higher than 225OC, determined by DSC and polarizing microscopy. Fliissig-kristalline Struktur yon Hauptketten-Polyurethanen auf Rasis yon 4,4'-Azobenzendiisocyanat Ausgehend von ~,4'-Azobenzendiisocyanat und Mono-, Di-, Triund Tetraethylenglycol wurden Polyurethane synthetisiert und deren Schmelzverhalten untersucht. Dabei zcigte sich, dall eines der resultierenden Polymere, Poly(oxycarbonylimino-4,4'-azobenzciidiyliminocarbonyloxyethylenoxyethylenoxyethylen) oberhalb von 325°C eine fliissigkristalline Phase aufweist, was durch DSC und unter dem Mikroskop bei polarisiertem Iicht bewiesen wurde. 3fCuaKo-~pucma4JzuuecKa~ cmpyKmypa nomypemanos na ocnoee 4,4'-a306en3onauu~ot+ua~ama peTaIIH H nccneAoBanocb M X cnnasneme. np11 TOM O K ~~~J I O C ~, YTO OAMH 113 nonyseHHbIx nonmepoB, n o m ( OKCH-

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