A SWITCHABLE LIQUID-CRYSTAL IMPREGNATED POROUS POLYMER DEVICE

This paper describes the fabrication and performance of a novel device based on liquid crystals dispersed in a polymer matrix. A low molecul ar weight Liquid crystal material is introduced into a pre-formed, thi n, porous, low density polymer film. Application of an electric field across the thin film produces a change in the transmission of the film just as in conventional Polymer Dispersed Liquid Crystals (PDLC) due to the reorientation of the liquid crystal director. Thus the device a cts as a shutter. One significant advantage of this type of device ove r conventional PDLC is that there is no intermixing of the liquid crys tal and monomeric material. Also compressible porous polymer matrices can be formed(1) giving the potential for controllably distorting the pores in a given direction. The formation and switching characteristic s of a device using a porous polymer based on styrene and divinylbenze ne is described.