INFLUENCE OF LIQUID-CRYSTAL CONCENTRATION ON THE ELECTROOPTICAL BEHAVIOR OF POLYMER-DISPERSED LIQUID-CRYSTAL FILMS PREPARED BY ELECTRON-BEAM PROCESSING

Polymer dispersed liquid crystal (PDLC) films can be switched electric ally from a light scattering off-state to a highly transparent on-stat e. Polymerization induced phase separation (PIPS) initiated by electro n beam irradiation has been used as a powerful method to obtain define d PDLC films. Blends of an aromatic polyester acrylate in additional m onomers were prepared as polymer matrix precursors. The eutectic nemat ic mixture E7 was used as liquid crystal material in this work. Mixtur es including different amounts of these materials were exposed to the electron beam radiation. The optical transmission properties of the ob tained PDLC films were investigated as a function of composition and a mplitude of the applied AC voltage. The electro-optical curves strongl y depend on the liquid crystal concentration and are highly reproducib le.