共聚芳酯N-B向列织构的退火研究

ANNEALING STUDIES ON NEMATIC TEXTURES OF AROMATIC COPOLYESTER B-N

液晶共聚芳酯B-N在不同温度下可制得细丝状、粗丝状、纹影状、大理石状和微滴状等各种向列织构.两种方法用于这些织构的研究,一种是化学刻蚀和扫描电镜观察,另一种是对织构的退火处理和偏光显微镜观察.两者都通过装饰在织构上的结晶的排列揭示了向错和分子指向矢分布的信息.观察到S=+1/2的线头、环状的线向错和Neel型畴壁.结果还表明,在液晶态温区的热处理能提高液晶的有序性和稳定性。

Five different nematic textures, i.e. tight and coarsethreadlike, Schlieren, marblelike and dropletlike texture, can be preparedfrom an aromatic copolyester B-N by treating at different temperatures.Two methods were used in the studies of these textures. One was chemicaletching and SEM observation, another was annealing and polarized micros-cope observation. Both revealed useful information about distribution ofdisclination and molecular director by the arrangement of crystals decoratedon the textures. The proofs of the thread ends with intensity S=+1/2,disclination lines with the form of close circus and the Neel domain wallcan be drawn. It also showed that heat treatment of textures at liquidcrystalline state increased the degree of order and stability of liquidcryatalline.