Dynamics of a nematic liquid crystal on a PBLG-CRA film. Time-resolved infrared spectroscopic study

The time response of a nematic liquid crystal (LC) to an applied electric field is proposed as a new dynamic index for the interaction between LCs and LC-orienting films. For a PBLG-CRA (chemical reaction alignment) film, the unique LC response observed by time-resolved infrared spectroscopy suggested a time-dependent LC-orienting effect induced by the film. On the basis of the electric field polarity dependence of the LC dynamics, we describe a model in which the applied electric field influences the orienting effect of the film, the latter originating from the inherent dipole moment of the film.