LIQUID-CRYSTALLINE PHASE-FORMATION BEHAVIOR OF CELLULOSE CINNAMATE

Cellulose cinnamates with degrees of substitution (DS) of up to 2.3 were prepared by a reaction of cellulose with cinnamoyl chloride in pyridine. The cellulose cinnamate was found to form a cholesteric liquid crystalline phase at the concentrations higher than a critical concentration in some organic solvents. The critical concentration showed tendencies to be higher for the cellulose cinnamate with higher DS and with higher degree of polymerization (DP). Influences of formation of liquid crystalline phase and of irradiation with UV light on the physical strength of the cellulose cinnamate film were investigated and both were found to make the breaking strength and modulus of elastisity of the film higher.