Phase Transitions of Ionic Liquid-Crystalline Polymethacrylate Having a Piperidinium Skeleton

Abstract

An ionic liquid-crystalline polymethacrylate [P-Pi/MeI having a piperidinium skeleton in a mesogenic side-chain was synthesized. Its nonionic family [P-Pi was also prepared, and phase transitions of P-Pi/ MeI and P-Pi were compared.

Both P-Pi/MeI and P-Pi exhibit enantiotropically smectic phases. Ionic P-Pi/MeI shows enhanced thermal stability in comparison with nonionic P-Pi. A temperature of P-Pi/MeI, at which an isotropic phase forms, is higher than that of P-Pi. P-Pi/MeI also shows a higher glass transition temperature when compared to P-Pi.

Also, nonionic and ionic low molecular weight model compounds were prepared, and their thermal properties were compared.

Key Words:

• ionic liquid-crystalline polymer
• piperidinium skeleton
• phase transition