A NEW BANDED TEXTURE IN SHEARED THERMOTROPIC LIQUID-CRYSTALLINE POLYMERS

Liquid crystalline polymers (LCP) often show after a shearing procedure a so-called banded texture as reported in the literature. The appearance of the banded texture is mainly influenced by the chemical structure of the LCP, the shear rate and the thickness of the layer. In addition to the well known banded texture a particular tractor texture (or herring-bone texture) can be obtained. By subsequent annealing of the sheared specimens at elevated temperatures the banded texture can be changed, especially in dependence on the thickness of the sheared layer. In some cases the banded texture remains unchanged, whereas in other cases it is transformed into a domain structure or into spherulites. © 1990 Chapman and Hall Ltd.