Dynamics of liquid crystal azimuthal anchoring at a poly(vinyl cinnamate) interface measured in situ during polarized UV light irradiation

摘要

An automated in situ technique for the measurement of the director reorientation at a nematic-aligning photosensitive polymer interface during polarized UV light irradiation has been developed. Using this technique, the photoinduced azimuthal anchoring energy (～20 merg cm~(-2)) and the adsorption part of the latter (～7 merg cm~(-2)) have been evaluated for the E7-poly(vinyl cinnamate) system. The kinetics of the director reorientation have been shown to be a very slow process (～1 h) and probably controlled by adsorption-desorption of liquid crystal molecules at the interface.