FLUORINATED DIPHENYL-DIACETYLENE AND TOLANE LIQUID-CRYSTALS WITH LOW THRESHOLD VOLTAGE

Abstract

Several new fluoro-alkoxy and alkenyloxy (alkoxy with a carbon-carbon double bond) diphenyl-diacetylene and tolane liquid crystals are synthesized and their physical properties evaluated. Double bond position is found to make a pronounced effect on elastic constant, phase transition temperature and heat fusion enthalpy, but little change on birefringence, dielectric anisotropy, and viscosity. These compounds exhibit a high birefringence, low viscosity, and low threshold voltage, and are particularly attractive for infrared light valves and polymer-dispersed liquid crystal displays.