Chitosan phenylcarbamate (CtsPC) samples were synthesized and their lyotropic liquid crystallinity in ionic liquids was investigated. 1-Ethyl-3-methylimidazolium dicyanamide ([C2Mim][N(CN)2]) was found to be a novel solvent for CtsPC, and the lyotropic system formed a cholesteric liquid-crystalline phase and exhibited vivid colorations owing to selective light reflection. The cholesteric helical pitch was controllable by polymer concentration, temperature or the degree of phenylcarbamoyl substitution. Although the helical sense of CtsPC/[C2Mim][N(CN)2] cholesterics remained right-handed under the adopted measurement conditions, an inversion of cholesteric sense was achieved by using a mixed solvent of [C2Mim][N(CN)2]/N,N-dimethylformamide.
- Junichi Sato
- Nobuhiro Morioka
- Yoshiyuki Nishio
