2021 Volume 34 Issue 6 Pages 571-578
The photo-alignment properties of 4,4-(hexafluoroisopropylidene) diphthalic anhydride (6FDA)-based polyimides with sterically hindered diamine component were systematically evaluated, such as 6FDA-3,3'-dimethylbenidine, 6FDA-2,7-diaminofluorene, 6FDA- 2,3,5,6-tetramethyl-1,4-phenylene diamine, 6FDA-2,5-diamino-1,4-phenylenediamine, 6FDA-1,4-phenylenediamine, and 6FDA-1,3-phenylenediamine. To evaluate sterically hindered diamine components, the diamine components with varying number of benzyl ring and methyl group were used. The polyimides containing the diamine components with methyl group were well planarity and forming charge transfer complex efficiently. The polyimides showing photo reaction property by linearly polarized ultra violet light induced photo alignment properties, however, the linear structured polyimide induced photo alignment property even it showed poor photo reaction property.
