THERMOTROPIC CHIRAL NEMATIC SIDE-CHAIN POLYMERS AND CYCLIC OLIGOMERS

For all the theoretical, experimental and computational research on ch iral nematic systems over the last four decades, understanding of chol esteric mesomorphism from the molecular perspective is still rather li mited at the present time. Nevertheless, the unique property of select ive wavelength reflection accompanied by circular polarization has pre sented tremendous potential for various optical applications. Theories governing optical birefringence and selective reflection bandwidth ar e outlined to serve as a foundation for molecular design. Both polymer ic and low molar mass glass-forming chiral nematics are surveyed in te rms of chemical structure, thermotropic and optical properties. Charac terized by relative ease of processing, the low molar mass approach is illustrated with our recent results in terms of design concept, mater ials synthesis and characterization. We also highlight outstanding iss ues that need to be addressed to help advance chiral nematics as a cla ss of advanced optical materials. Copyright (C) 1996 Elsevier Science Ltd