Comparison Study on Thermally Stimulated Photoinduced Orientation of Liquid Crystalline Polymer with Cinnamate Side Groups using 313 nm and 365 nm Light

Polymethacrylates with different type of cinnamate side groups (P1, P2 and P3) were synthesized, and their photochemical and photoinduced reorientation behaviors were investigated using linearly polarized (LP) 313 nm and 365 nm light. P1 and P2 exhibited liquid crystalline (LC) characteristics, but P3 did not. Thin P1 and P2 films underwent thermally stimulated photoinduced molecular reorientation using LP 313 nm or 365 nm light and subsequent annealing, where adjusting the exposure energy and the exposing light wavelength could control the reorientation direction. Type of the cinnamate side groups, resultant photoproducts, and LC characteristics of the polymer played an important role in the thermally stimulated photoinduced molecular reorientation directions and their performances.