乙基氰乙基纤维素溶致液晶的缺陷结构观察

OBSERVATIONS OF DEFECTS IN LYOTROPIC LIQUID CRYSTALS OF ETHYL-CYANOETHYL CELLULOSE

乙基氰乙基纤维素在许多溶剂中都可以形成胆甾型液晶溶液。在液晶溶液中出现多种向错结构。本文利用偏光显微镜和电子显徽镜对液晶溶液中出现的向错结构进行了全面的观察。观察到了λ,τ和x向错线以及各种由具有相反符号的λ和τ向错线组成的向错对,其结构特征与小分子胆甾型液晶相结构特征相似。

Ethyl-cyanoethyl cellulose [(E—CE)C] forms cholesteric lyotropic liquid crystals in many organic solvents and the mesophase shows multi-texture. In the (E—CE) C/dichloroacetic acid (DCA) liquid crystalline solutions, the existence of the λ,τ and χ disclinations are observed by a polarizing microscope. Within the mesophase with band--like texture, pairs of disclinations are often observed. A lot of disclinations are observed in the (E-CE)C/polyacrylic acid (PAA) composites by transmission electron microscopy, which are similar to those observed by optical microscopy in (E-CE) C/DCA systems.