Molecular orientation and alignment of rubbed poly(vinyl cinnamate) surfaces

We observed that weakly and strongly rubbed polyvinyl-cinnamate surfaces align liquid crystal films perpendicular and parallel to the rubbing direction, respectively. Surface-specific sum-frequency vibrational spectroscopy was used to probe molecular orientations and alignments of the rubbed surfaces and provide a molecular-level understanding of the observation. (c) 2006 American Institute of Physics.