Polymer dispersed liquid crystal films prepared by electron beam curing: Influence of the nature of the polymer precursor

Polymer dispersed liquid crystal (PDLC) films were prepared by a polymeriza tion induced phase separation (PIPS) process of mixtures composed of monome rs and the nematic liquid crystal (LC) E7. Electron beam (EB) radiation was employed to initiate the PIPS process. Mixtures of the LC E7 and selected well characterized di- and tri-functional acrylate monomers as polymer prec ursors have been exposed to a defined amount of dose of EB radiation. Tripr opylene-glycoldiacrylate (TPGDA), propoxylated glyceroltriacrylate (GPTA), and a 1:1 mixture of these materials were used as monomers. The concentrati on of E7 in the initial mixture was kept constant at 70 weight-%, It was sh own that the electro-optical properties strongly depend on the nature and t he functionality of the monomers.