Adsorption-desorption hysteresis behavior of liquid crystalline molecules onto polymer surface

Abstract

Adsorption-desorption characteristics of cyano-phenyl type liquid crystal (LC) molecules onto rubbed polyimide and poly(vinyl alcohol) substrates were investigated by means of optical ellipsometric analysis. The LC molecules in a dilute solution irreversibly adsorbed on the rubbed polymer surface. Adsorbed mono- or bi-layer of LC molecules was formed even after almost complete rinse of the polymer surface with a solvent, indicating a stronger adsorption than a simple physical adsorption.