CHOLESTERIC LIQUID-CRYSTALLINE POLYESTERS .1. CHOLESTERIC LIQUID-CRYSTALLINE COPOLYESTERS BASED ON POLY(CHLORO-1,4-PHENYLENE TRANS-1,4-CYCLOHEXANEDICARBOXYLATE)

Thermotropic copolyesters exhibiting cholesteric mesophases were prepared by introducing chiral (R)-3-methyladipate units into rigid poly(chloro-1,4-phenylene trans-1,4-cyclohexanedicarboxylate), and a morphology study of the solid cholesterics was examined by using a transmission electron microscopy method. The transmission electron micrographs showed a series of dark and bright striation lines which were attributed to the periodic structure of the cholesteric helix. Defects or imperfections such as disclinations and edge dislocations of the cholesteric layer texture were elucidated from the micrographs. These cholesteric copolyesters were also characterized by DSC, spectroscopic, and optical microscopic methods.