This proposal consists of two parts: I. Investigation of phase behavior and molecular order in thermotropic main-chain polymer liquid crystals (PLCs); II, Synthesis and properties of ionomeric PLCs, a new family of structures with a multiplicity of ionic charges. The objectives of this research are to contribute to understanding of fundamental aspects of molecular and supramolecular order in PLCs, and directed design of high performance materials. Model systems for testing theoretical predictions are expected, as well as materials with nteresting mechanical, opto-electronic and transport properties. In the case of main-chain PLCs, the following investigation of mesophase behavior will be carried out: global chain anisotropy, polymorphism, miscibility, properties of ordered polymer glasses. Both inherently flexible and semiflexible chains are considered. Novel main-chain and side-chain ionomeric PLCs, including structures derived from substituted ionic polyacetylenes, will be synthesized. Thermotropic and lyotropic phase behavior will be studied as well as formation of ordered polyelectrolyte complexes.
