THERMAL AND DIELECTRIC-PROPERTIES OF 2 SIDE-CHAIN LIQUID-CRYSTALLINE HOMOPOLYMERS AND THEIR CORRESPONDING EQUIMOLAR COPOLYMER AND BLEND

The thermal and dielectric relaxation properties of two liquid crystal line homopolymers and their equimolar copolymer and physical blend are examined. The thermal properties of the copolymer are found to be a w eighted mean of the homopolymers, whilst the blend was predominantly t wo-phase but showed some indications of miscibility. Dielectric relaxa tion measurements indicated that, in the liquid crystal state, the rel axation times of all homopolymers and copolymers were similar at any g iven temperature, indicating that it is the polymer backbone relaxatio n which dominates the motion of the coupled, polar mesogens. The blend relaxation appears to be a weighted average of the two components, in dicating that dielectric relaxation can be used as a sensitive indicat or of liquid crystal polymer blend miscibility. (C) 1998 Elsevier Scie nce Ltd. All rights reserved.