SYNTHESIS AND PROPERTIES OF THE BLOCK-COPOLYMERS OF POLY(ETHER ETHER KETONE) AND THE POLY(ARYL ETHER SULFONE) CONTAINING BIPHENYLENE MOIETY

The block copolymers of poly(ether ether ketone) (PEEK) and poly(aryl ether sulfone) containing biphenylene moiety (PEBS) were synthesized b y a condensation reaction of fluorine-terminated PEEK oligomers and hy droxy-terminated PEBS oligomers. The content of PEBS in the copolymers was varied from 10 to 37 wt%, and the effect of the compositional var iation on the properties was investigated. Microphase separation was n ot observed and the copolymer was a homogeneous system having good com patibility. The crystal structure of the copolymers is rhombic, equal to PEEK. Although the degree of crystallinity of the copolymers decrea sed with the increase of PEBS content, the glass transition temperatur e (T-g) rose greatly, and superior heat resistance and good mechanical properties at high temperature were obtained. Analyses of the isother mal crystallization kinetics of the copolymers provided an Avrami's ex ponent (n) of 2.0. (C) 1997 Elsevier Science Ltd.