摘要
综述了主链型高分子液晶向列相向错在实验观察方面的进展。从纹影织构的观察和展曲、弯曲弹性常数相等条件下的二维曲率弹性理论出发探讨了向错结构的几何特征。简要涉及了弹性常数不相等对向错的影响、向错核心的本质和反转墙的观察；给出了拓扑强度ｓ高达４的高阶向错的实验观察结果；归纳出描绘向错周围指向矢场的主要实验方法：１）片晶装饰；２）条带织构装饰；３）表面微裂纹装饰。本文对上述方法进行了讨论和比较，列举了一些电子显微镜和光学显微镜照像的图例。
Experimental observation of disclinations of main-chain nematic polymers is re-viewed.The geometry of disclination structure is dicussed both from observations of schlieren texture and the theory of curvature elasticity for a two-dimensional case with equal splay and bend moduli.The effects of unequal elastic moduli,the nature of the disclination core and the observation of inversion walls are briefly mentioned.Examples of experimental observation of disclinations of high topological strengths up to s=4 are given.The main experimental methods to map the director field around disclinations are 1)lamellar decoration,2)band-texture decora-tion and 3)surface microcrack decoration.The methods are discussed and compared.Examples illustrated by electron micrographs or photomicrographs are presented.
出处
《化学进展》
SCIE
CAS
CSCD
1996年第1期1-16,共16页
Progress in Chemistry
关键词
高分子液晶
向列相
向错
液晶
main-chain liquid crystalline polymer
nematic mesophase
disclination
