Design, Synthesis And Properties Of Chiral Liquid Crystal Materials

This paper briefly introduced the development of liquid crystal materials for display, the structure characteristic of liquid crystal molecule, the latest research of liquid crystal display and therole of chiral dopants for liquid crystals. The relationship between chiral dopants'performance and their structure have be analyzed. According to this guide, two series of new chiral dopants for liquid cryatal were synthesized, and the reaction conditions were optimized. The main work of this paper was as follows:Chiral dopants is a important part of liquid crystal materials, especially in the application of cholesteric phase liquid crystals. In this paper, two series of new chiral dopants were designed and synthesized by derivative of chiral mandelic acid as a chiral reagent, which is easily obtained and low-cost. The appropriate reaction conditions were obtained.A series of 1-phenylethane-1,2-diyl bis(4'-(4-alkylcyclohexyl)biphenyl-4- carboxylate) were synthesized by the dehydration and catalysis of N,N'-dicyclohexylcabodiimide (DCC) through esterification. The productions were obtained with retention of configuration by mild reactions and high yields. Two compounds were synthesized.Chiral dopants contain 1,3-dioxolane group were synthesized by p-toluene sulphonic acid through acetalization reactions. The optical selectivity and conversion of the reaction was high. This series of chrial dopants have never been reported to the best of our knowledge. Six compounds were synthesized.All prepared solid compounds'melting points were tested, and the molecule structures were identified by IR, 1HNMR and 13CNMR, the specific rotation of chiral dopants were tested, the liquid crystal phase states of liquid crystal compounds were confirmed by DSC.