含氟光敏单体液晶光控取向膜的光谱研究

Spectral Studies on Liquid Crystal Photoalignment Film of Photosensitive Monomer with Fluorinated Groups

制备了含氟光敏单体材料六氟戊二醇双肉桂酸酯,实验发现该材料在线性偏振紫外光辐照下可发生定向光交联反应。通过紫外可见光谱与红外光谱分析,表明光交联类型为[2+2]环加成反应。用原子力显微镜对单体光聚后形成的聚合物取向膜表面进行扫描,未观察到明显的各向异性分布现象。实验测得取向膜诱导液晶分子平行排列,取向效果均一,薄膜预倾角为1°～2°。

2,2,3,3,4,4-hexafluoro-i,5-pentanediol dicinnamate ester, which could be crosslinked under irradiation of linearly polarized ultraviolet light, was synthesized in the present work. UV-Visible spectra and FTIR spectra revealed that [2＋2] cycloaddition was the main reaction of the monomer, but there was no clear morphological anisotropy on the surface of the obtained photoalignment film through atomic force microscopic analysis. The photoalignment film Could induce homogenous alignment of liquid crystal and the alignment is uniform. It was found that the pretilt angle of the photoalignment film is 1°-2°.