ABSTRACT

A series of star-shaped liquid crystal (LC), respectively, based on phloroglucinol, pentaerythritol and glucose as cores, rod-shaped molecules (MeOSBAA, MeSBAA and ClSBAA) containing a schiff base as mesogenic mesogen were synthesised. The molecular structures were confirmed by FT-IR and ¹H-NMR techniques. The LC textures and thermal phase behaviours were investigated by polarising optical microscopy and differential scanning calorimetry. The results showed that MeOSBAA and ClSBAA were thermally enantiotropic liquid crystals. Three-arm star LC macromolecules X-SBA3E and four-arm star LC macromolecules X-SBA4E were found to display enantiotropic nematic liquid crystals behaviour. While the five-arm star-shaped chiral LC molecules X-SBA5E exhibited enantiotropic chiral nematic phase.

摘要

合成了一系列以间苯三酚、季戊四醇和葡萄糖为核心，以席夫碱为介晶的棒状分子（MeOSBAA、MeSBAA和ClSBAA）的星形液晶（LC）。分子结构由FT-IR和¹ H-NMR技术证实。通过偏振光学显微镜和差示扫描量热法研究了液晶结构和热相行为。结果表明MeOSBAA和ClSBAA是热对映性液晶。三臂星形LC高分子X-SBA3E和四臂星形LC高分子X-SBA4E发现显示对映向列液晶行为。而五臂星形手性液晶分子X-SBA5E 则表现出对映手性向列相。