The morphology of liquid crystalline polymers and their blends /

THE MORPHOLOGY OF LIQUID CRYSTALLINE POLYMERS AND THEIR BLENDS MAY 1993 KEVIN ROMAN SCHAFFER, B.S., NORTH CAROLINA STATE UNIVERSITY M.S., NORTH CAROLINA STATE UNIVERSITY M.S., UNTVERSITY OF MASSACHUSETTS Ph.D., UNIVERSITY OF MASSACHUSETTS Directed by Professors Richard J. Farris and Edwin L. Thomas Nematic liquid crystals polymers (LCPs) encompass a large class of macromolecules exhibiting orientational order when in the melt or solution state. The intrinsic local orientation of these materials yields processing advantages due to lower viscosities than related isotropic (flexible coil) polymers of comparable molecular weight. Highly directional moduli and strengths in the solid state are further benefits of the ease of obtaining high orientations during processing in the melt or solution. Blending and composite fabrication with other materials are the practical methods that must be developed to use LCPs for structural applications. A nematic liquid crystal polymer such as poly(p-phenylene benzobisthiazole) (PBZT) is a rigid rod macromolecule with its length being essentially the mesogenic unit. Such rigid rod polymers are usually lyotropic liquid crystals and are infusible in the