Deformation Studies of Liquid Crystalline Polymers

Oriented liquid crystalline polymers exhibit a macroscopic optical effect which appears as a sequence of bright and dark bands perpendicular to the orientation direction. Although these bands appear to be similar to the Williams domains in low molecular weight liquid crystals, their interpretation must satisfy not only the optical observations but also the rheological properties of the mesophases and the high mechanical properties typically exhibited by the oriented polymer morphologies produced by processing such mesophases. In view of these criteria, we discuss the formation of band patterns in thermotropic and lyotropic polymer systems and propose that the band patterns result from the ordering of macroscopic domains.