Novel chiral liquid crystal with two chiral butyl lactate chains exhibiting several frustrated mesophases including smectic Q and TGB phases separated by an optically isotropic phase

Abstract

A novel symmetric liquid crystalline compound with two chiral butyl lactate chains, (S,S)-bis[4-(1-butoxycarbonyl)ethyloxycarbonyltolanyl]fumarate (BisBLOCTF), was synthesized. This compound was found to exhibit a very unusual phase sequence involving several frustrated mesophases, namely smectic Q, TGBC, TGBA and blue phases. In addition, an “optically isotropic” phase occurs between the smectic Q and the SmC*, and TGB phases. The different phases were studied by optical observation, DSC, X-ray diffraction and helical pitch measurements. Changing the nature of the chiral chains reduces the sequence to only a smectic Q mesophase.