PREPARATION AND CHARACTERISTICS OF CHOLESTERIC GEL FROM PENTYL ETHER OF HYDROXYPROPYL CELLULOSE

A new cellulose derivative, pentyl ether of hydroxypropyl cellulose (P -HPC), and its crosslinked gel (PG-HPC) were prepared in non-aqueous s olution. The temperature dependence of the optical pitch for the therm otropic mesophases formed by P-HPC and PG-HPC was determined spectrosc opically. PG-HPC displayed the cholesteric reflection colour at room t emperature and its cholesteric order and structure were fixed on heati ng up to 90 degrees C. The optical pitch of the redried gel of PG-HPC, after swelling in tetrahydrofuran (THF), was shifted to lower wavelen gth and the reflection band became narrower than that of the original, before swelling in THF.