Synthesis and Characterization of Ferroelectric Liquid Crystalline Siloxanes Containing 4-Hydroxyphenyl(2S,3S)-2-Chloro-3-Methylvalerate

摘要

New series of organosiloxane ferroelectric liquid crystalline materials have been synthesized, and their mesomorphic and physical properties have been characterized. These new series contain bis-siloxane or tris-siloxane unit attached to the flexible alkyl chain end of (2S,3S)-2-chloro-3-methylvalerate. The siloxane molecule induction is helpful to the chiral smectic C (S_C*) formation and chiral S_C* stabilization, and it simultaneously causes the liquid crystal temperature range of chiral S_C* to be broader. The siloxane member is helpful in reducing the smectic C (S_C) transation shift temperature, and the molecule containing tris-siloxane units shows better effect than the bis-siloxane one. The synthesis and characterization of the new FLCs materials which exhibit S_C* phase at room temperature and higher spontaneous polarization are presented.