Transmission electron microscopy study of an oriented thermotropic liquid crystalline polymer

Abstract

Electron microscopy studies of fibers spun from lyotropic polymer mesophases are far more common in the literature than reports of TEM of thermotropic polymers, but recently publications have appeared reporting oriented electron diffraction patterns and “banding” in TEM images of thermotropic polyesters. Considering the advantages of fiber spinning from the melt, an understanding of the detailed morphology of thermotropic polymers, their ordering in flow fields, and the influence of quenched-in mesomorphic orientation on 3-D crystalline order is desirable. The experimental study described herein utilizes a solution casting technique to produce oriented thin films of a block polyester containing alternating rigid mesogenic and flexible spacer groups (Fig. 1a).