Effects of Side Chains with Similar Lengths and Different Structures of Polyimides on Liquid Crystal Alignment Behavior  

作　　者：Jia-hao Xia Ying Jiang Shi-ming Gong Zhen Sun 汪映寒 

机构地区：[1]State Key Laboratory of Polymer Materials Engineering of China [2]College of Polymer Science and Engineering,Sichuan University

出　　处：《Chinese Journal of Polymer Science》2014年第12期1610-1619,共10页高分子科学（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Nos.50973067 and 51173115);the Ministry of Education (the Foundation for Ph.D.training,Grant No.20110181110030) of China

摘　　要：Polyimides（PI） with different side chains in structure were synthesized by copolycondensation of pyromelliticmdianhydride（PMDA） with 3,5-diamino-（4＇-methane acid hexyl ester） phenyl-benzamide（C6-PDA）,（4-butoxybiphenol）-3＇, 5＇-diaminobenzoate（C4-BBDA） and 3, 5-diamino-benzoic acid decyl ester（C10-DA） named PI-PDA, PI-C4, PI-DA, respectively. The lengths of side chains of PI-PDA and PI-DA are as similar as that of PI-C4. Through the pretilt angle tests it is demonstrated that neither the structure of side chains nor the rubbing process could make an obvious difference on vertical alignment property when the lengths of the side chains are similar, standing at around 1.6 nm. The measurement of surface energy of PI surfaces further proved this result. The result of the X-ray photo-electron spectroscope measurement indicated that the side chains of PIs stretched out from the polymer bulk phase and accumulated on the surface.Polyimides（PI） with different side chains in structure were synthesized by copolycondensation of pyromelliticmdianhydride（PMDA） with 3,5-diamino-（4＇-methane acid hexyl ester） phenyl-benzamide（C6-PDA）,（4-butoxybiphenol）-3＇, 5＇-diaminobenzoate（C4-BBDA） and 3, 5-diamino-benzoic acid decyl ester（C10-DA） named PI-PDA, PI-C4, PI-DA, respectively. The lengths of side chains of PI-PDA and PI-DA are as similar as that of PI-C4. Through the pretilt angle tests it is demonstrated that neither the structure of side chains nor the rubbing process could make an obvious difference on vertical alignment property when the lengths of the side chains are similar, standing at around 1.6 nm. The measurement of surface energy of PI surfaces further proved this result. The result of the X-ray photo-electron spectroscope measurement indicated that the side chains of PIs stretched out from the polymer bulk phase and accumulated on the surface.

关 键 词：Polyimides Homeotropic alignment Liquid crystal. 

分 类 号：O631.13[理学—高分子化学]