Ferroelectric liquid crystals consisted of butyl lactate and 3-naphthyl-propenoic acid derivatives

Abstract

3-(6-alkyloxy-2-naphthyl)propenoic acids were connected by phydroxybenzoic acid to L-(-)-ethyl lactate and L-(-)-butyl lactate, CnONPBLC₂ and CnONPBLC₄, respectively. CnONPBBLC₄ series was obtained with one p-hydroxy benzoic acid unit more as the core. CnONPBLC₂, n=6, 8, 10 and 12, exhibited enantiotropic smectic A (S_A) phase in the range of 60 to 120 [ddot]C. Monotropic chiral smectic C (S_c*) phases were observed for n=10 and 12. CnONPBLC₄ series exhibited enantiotropic S_A phases. S_c* phases were observed for n=8 and 9 monotropically and n=12 and 14 enantiotropically. CnONPBBLC₄ exhibited enantiotropic S_c* and S_A phases. The transition temperatures for crystal to S_c*, S_c* to S_A and S_A to Iso were 80, 170 and 220 [ddot]C, respectively. Extremely wide temperature range for S_c* phase was observed. The values of Ps and tilting angle of C₁₂ONPBLC₄ were 54 nC/cm² and 22 degrees, respectively, at 30 [ddot]C below the S_A-S_c* transition.