MAIN-CHAIN LIQUID-CRYSTALLINE IONIC POLYMERS WITH THERMOTROPIC AND LYOTROPIC MESOPHASES

An ionogenic main chain liquid crystalline polymer was synthesized. In contrast to previous studies the charged sites were incorporated into the flexible spacer and not into the mesogenic group. This was done through quaternization of 1,2-bis(4-pyridylethane) with a biphenyl-4,4'- nonanoxytoluenesulphonate. The polymer displayed thermotropic and lyotropic mesophases. The thermotropic mesophase was smectic. Organic counterions such as methylsulfonates and p-toluenesulfonates were found to be favorable to the development of mesophases, due to the increased solubility and lower isotropisation temperatures, when compared to bromide counterion containing polymers. Easy supercooling, dependence on thermal history, and the development of batonnet textures on cooling from the melt were also observed. (C) 1995 John Wiley & Sons, Inc.