Novel liquid crystalline composites composed of a nematic two-frequency-addressing liquid crystal and organized clay mineral have been prepared. The particles of the clay mineral were dispersed homogeneously in the liquid crystal. The composite cells displayed a reversible and multistable electro-optical effect between transparent and turbid light scattering states by changing the frequency of the electric field. The light transmittances of both transparent and light scattering memory states did not change after 15 hrs without the electric field applied.

A bisphenol A epoxy resin is used to modify compatibility between PC and LCP (Vectra B950, a wholly aromatic liquid crystalline polymer) during injection molding. LCP can effectively reinforce PC, since it forms in situ micro-fibrils in the thermoplastic PC matrix during melt flow. However, the immiscibility of PC and LCP affects the mechanical performance of the LCP in situ composite. Preliminary results of this work indicate that epoxy might improve the interfacial bonding between PC and LCP fibrils, and also modify the tensile properties of the PC/LCP system.

Some features of the: formation of liquid-crystal structures based on polymer complexes are discussed for composites of polyvinyl alcohol with cellulose esters, polyacids, inorganic acids and variable-valence metals. Rheological and optical methods of research as well as a dielectric relaxation method have revealed the formation of several types of interpolymer complexes in liquid flowable media. This leads to formation of associates and results in an increase of the molecular mobility of macromolecules and their fragments. The structure and properties of the complexes depend on the media compositions and on the method of additive introduction. The composites obtained -can be used for producing light-, electric- and heat-sensitive film materials and sensors of various types.

Holographic photo-curing of a penta-acrylate monomer-liquid crystal mixture forms a unique system of liquid crystal microdomains confined to Bragg planes. We examine the physics of this structure as it relates to the formation of electrically switchable holograms, for which many potential applications exist. The results of scanning electron microscopy and laser characterization studies lead to the development of concepts and models for explaining the microscopic morphology and electro-optical properties of these holograms. We find that a model incorporating a shaped-droplet analysis of the electro-mechanical properties of LC domains combined with standard coupled-wave theory of holography offers good numerical agreement with diffraction efficiency data for ppolarized probe light.