High Birefringence Phenylacetylene Liquid Crystals with Low Viscosity

Abstract We have synthesized new high Δ n 3-ring phenylacetylene(3PA) liquid crystals which have substituent groups with core center phenyl ring and investigated the effects of substitution on physical properties. Nematic range and viscosity were improved remarkably with keeping high Δ n by introducing trifluoromrthoxy group. The Δ n of 3PAs were also descussed with relationship of polarizability and order parameter.