光敏小分子单体链聚合诱导液晶分子排列的研究

Homogeneous Alignment of Nematic Liquid Crystal Induced by Polymerized Photosensitive Monomers

两端带有碳碳双键 ,尺寸与液晶分子相近的刚性小分子单体在线偏振紫外光照射下聚合 ,形成的聚合物膜能够诱导液晶分子均匀取向。对不同光照时间的紫外吸收光谱谱图比较发现 ,该取向材料具有较好的光敏性。利用偏振红外光谱测定了取向膜表面的二向色性 ,并且测得膜表面有序度为 0 .0 88。以晶体旋转法测定该取向膜制成的液晶器件 ,测得预倾角的大小为 0 .8°。

The monomers with vinyl groups at two ends of the main chain after exposed to linearly polarized ultraviolet (LPUV) light can induce homogeneous alignment of liquid crystal molecules. The monomer films were coated on the surface of glass substrates and then directly illuminated by LPUV. UVvisible spectra and polarized FTIR spectra elucidated photochemical reaction degree and the anisotropy IR absorption. The orientation order of the photoaligned film is 0.088. The pretilt angle of liquid crystal device made by this material was small and attained 0.8 degree.