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Dynamic mechanical properties of quinazolone–imide block copolymer

✍ Scribed by Akira Fukami; Katsuyoshi Iisaka; Shigeru Kubota; Shouhei Etoh

Publisher
John Wiley and Sons
Year
1991
Tongue
English
Weight
479 KB
Volume
42
Category
Article
ISSN
0021-8995

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✦ Synopsis

Dynamic mechanical properties have been investigated over the temperature range of -150-360°C for the quinazolone-imide copolymers, prepared by condensation of the amine-terminated quinazolone prepolymer with a stoichiometric quantity of pyromellitic dianhydride or 3,3',4,4'-benzophenone-tetracarboxilic dianhydride. Both copolymers have, respectively, the low-temperature @-relaxation and the p*-relaxation, as well as the case of poly (4,4'oxydiphenylene-pyromellite-imide) (Kapton) examined for comparison. These relaxations seem to contribute to toughness of the copolymers. The a-relaxations for both copolymers occurred at much the same temperature of 320°C, which can be assigned to a large scale segmental motion of the quinazolone chain sequence. The a-peak temperatures shifted into higher temperatures by heat aging. This can be explained in terms of crosslinking in the copolymers, supported by swelling test in hot rn-cresol and IR spectroscopy.

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