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 his-siloxane or tris-siloxane unit attached to the flexible alkyl chain end of(2S,3S)-2-cliloro-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 (Sc) transation shift temperature, and the molecule containing tris-siloxane units shows better effect than the his-siloxane one. The synthesis and characterization of the new PLCs materials which exhibit S_c~* phase at room temperature and higher spontaneous polarization are presented.