Studies of liquid crystal alignment on the surface of polyvinylfluorocinnamate photoalignment layer

In order to understand the induction mechanism of the liquid crystal director, structural changes of photosensitive polyvinylfluorocinnamate with UV irradiation were investigated using FTIR and UV/Vis spectroscopy It was found that optical anisotropy was induced in the film by irradiation of linearly polarized UV light onto the isotropic polymer film, and such anisotropy in the film determined the direction of the liquid crystal director. The groups in the polymer, which are preferentially aligned perpendicular to the polarization direction after the UV exposure, induce liquid crystal alignment perpendicular to the polarization direction of UV via dispersive intermolecular interactions.