Thermal and ionic-conductive behaviors of liquid crystalline polymers withalkali metal salt

In order to investigate the relationship between ionic conductivity and liq uid crystallinity, we prepared the main-chain type polyester having 1,4-bis styrylbenzene units and ethyleneoxide chain in the repeating unit. The main -chain type polyester with lithium salt at the ratio of 0.04 per polymer re peating unit exhibited a smectic phase. However, the polyester with lithium salt (0.11) showed a nematic phase. The ionic conductivity of the polyeste r with lithium salt increased with increasing lithium salt concentration. The trans-type polyester exhibited a liquid crystalline phase, while the ci s-type polyester did not show any mesophase. We found that the ionic conduc tivity of the trans-type polyester with lithium salt (0. 11) was larger tha n that of the cis-type polyester with lithium salt (0.11). However, a liquid crystalline phase was found in the side-chain type polyet her with alkoxy chain length of below 12. A smectic phase was induced for t he nonmesomorphic polyethers with lithium salt. The layer spacing of the sm ectic A phase for the non-mesomorphic polyether with lithium salt decreased from 55 to 41 Angstrom with increasing temperature. The ionic conductivity of the polyether with lithium salt increased with decreasing the layer spa cing. Copyright (C) 2001 John Wiley & Sons, Ltd.