Some Properties of Nematic Liquid Crystal E7/Acrylic Polymer Networks

Abstract

Polymer Dispersed Liquid Crystal films were elaborated by photopolymerization using ultraviolet radiation of liquid crystal/monomer mixtures. Three acrylic difunctional propyleneglycol based monomers were used; differing only by their chain lengths in terms of their molecular weight. Infrared spectroscopy investigation made it possible to obtain the monomer conversion rates, in order to determine the effect of the presence of liquid crystal on the kinetics of polymerization and phase separation. The characterization by linear dielectric spectroscopy of the monomers and polymers was carried out as a function of temperature in the frequency range from 20 Hz to 1 MHz.