Orientation of Polymer Molecules in Rubbed Alignment Layer and Surface Anchoring of Liquid Crystals

In order to better understand liquid crystal alignment on a rubbed polymer surface, the authors investigated the relationship between the orientation of polymer molecules and the surface anchoring strength of liquid crystals on a rubbed surface. Measuring the IR-absorption and the optical retardation, it was found that the polymer molecules were oriented parallel to the rubbing direction. The order of molecular orientation in the polymer and the surface anchoring strength of liquid crystal both increased with the rubbing strength.