Measurement of azimuthal anchoring energy at liquid crystal/photopolymer interface

The photopolymer material of poly(vinyl cinnamate) (PCVi) has been used to investigate the contribution of the anisotropic van der Waals force to the azimuthal anchoring energy in a pentyl cyanobiphenyl (5CB)/PVCi system. The optical anisotropy of a PVCi film is precisely controlled Lq varying the exposure time of linearly polarized UV light. and the azimuthal anchoring energy in the film is estimated by measuring the the width of the Neel nail. The result shows that the azimuthal anchoring energy in the 5CB/PVCi system increases exponentially with increasing optical anisotropy, indicating the existence of additional contributions to the LC alignment.