Side chain liquid crystal polysiloxanes and their low Tgcopolymer analogues

Abstract

A number of side-chain liquid crystal homopolymers derived from poly-(hydrogenmethylsiloxane) and their copolymeric analogues with the same mesogenic side chains appended to a poly(hydrogenmethyldimethylsiloxane) backbone have been prepared. The homo and copolymers exhibit the same mesophase types, but markedly different T_g values, mesophase transition temperatures and isotropisation enthalpies. These differences are interpreted in terms of the relative DP values and flexibilities of the backbones for the homo and copolymers.