LINEAR PRECURSORS OF LIQUID-CRYSTALLINE THERMOSETS

Polycondensation of glutaric acid with a diglycidyl terminated mesogen ic molecule [p-(2,3-epoxypropoxy)-alpha-methylstilbene] was carried ou t with a basic catalyst. A variety of novel main chain thermotropic li quid crystal oligoesters were synthesized via a short melt-copolyconde nsation process, by using different ratios of co-monomers. Preliminary studies by thermogravimetric analysis, differential scanning calorime try, steric exclusion chromatography and Fourier transform infrared sp ectroscopy have been carried out on the reacting mixtures in order to optimize the reaction conditions (temperature; time). Carbon-13 nuclea r magnetic resonance was used to identify the material structure. The mesophase stability ranges of the oligoesters were evaluated by means of DSC and optical polarizing microscopy. X-Ray diffraction analysis w as applied to determine the nature of the mesophase.