报道了一类新型相邻柔性长支链聚酰亚胺液晶垂直取向剂的合成, 并考察其用于液晶显示元件的性能表现。首先, 以2,3,4-三氟硝基苯、4-(4-庚基环己基)-苯酚、邻苯二甲酰亚胺钾盐等原料合成了含有相邻柔性长支链结构的新型功能性对苯二胺(L-14), 通过核磁共振波谱(NMR)和高压液相色质联用(HPLC-MS)对目标产物进行结构表征。用1,2,3,4-环丁烷四甲酸二酐(CBDA)、对苯二胺(PDA)和L-14制备了一类PDA与L-14不同比例的聚酰亚胺液晶垂直取向剂, 并对以该聚酰亚胺膜作为液晶取向层制得的液晶显示元件开展了预倾角、液晶定向时间、陡度、对比度等性能测试。结果表明, 基于该新型聚酰亚胺液晶垂直取向膜的液晶显示元件耐磨性能强、液晶定向时间短、取向性能优良、显示画面清晰。

The synthesis of a new polyimide liquid crystal vertical alignment agent substituted with adjacent double long side chains was reported, and its performance for liquid crystal display elements was investigated. First, 2,3,4-trifluoronitrobenzene, 4-(4-heptylcyclohexyl)-phenol, phthalimide potassium salt and other raw materials were used to synthesize a functional diamine (L-14) substituted with adjacent double long side chains. The diamine L-14 was characterized by NMR and HPLC-MS. Then a kind of polyimide liquid crystal vertical alignment agents were prepared using 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA), p-phenylenediamine (PDA) and L-14 with variant ratio of L-14/PDA. The liquid crystal display elements prepared with thus obtained polyimine film as the aligning layer were subjected to performance tests such as pretilt angle, liquid crystal aligning time, steepness, and contrast. The results show that the liquid crystal display elements based on the newly synthesized polyimide liquid crystal vertical aligning film possess strong abrasion resistance, short liquid crystal aligning time, excellent orientation performance, and clear display image.