Photoinduced orientation of photo-cross-linkable H-bonded liquid crystalline films and application to LC photoalignment layer

Abstract

Polymethacrylate liquid crystalline polymer comprising 4-oxycinnnamic acid (Figure 1) was synthesized and characterized. In this polymer, liquid crystalline nature was generated due to the hydrogen(H)-bonds between two cinnamic acid groups. The molecular orientation was induced by linearly polarized ultraviolet (LPUV) light and heat-treatment under liquid crystal temperature of the film. The orientation behavior of the film is determined by polarization UV and FTIR spectroscopies. Furthermore, homogeneous alignment control of low-molecular liquid crystals on films is demonstrated both perpendicular and parallel to the electric vector by adjusting the exposure energy.