Preparation of polymer-dispersed liquid crystal films containing a small amount of liquid crystalline polymer and their properties

Polymer-dispersed liquid crystal (PDLC) films were synthesized by the copol ymerization of liquid crystalline polymer (LCP) precursor, urethane acrylat e (UA), and mesogenic monomer (AI) at different conditions. The morphology of polymer matrix changed with the weight ratio of polymer/liquid crystal ( LC) ratio and curing temperature, resulting in a large change in the drople t size of LC domains in the PDLC film. The components used in the synthesis of polymer matrix, that is, the weight ratio of LCP, AI, and UA, also stro ngly influenced the morphology of PDLC films. A small amount of LCP was cop olymerized with UA and AI in the preparation of polymer matrix to improve t he electrooptical properties such as the viewing angle. Added LCP also affe cted the morphology and the properties of PDLC. The hydrophobicity of LCP c aused changes in the droplet size of LC domain in PDLC films and the anchor ing energy between matrix polymer and LC droplets. As the hydrophobicity of the matrix increases, the droplet size of LC domain also increases; on the contrary, anchoring energy decreased, leading to the decrease of driving v oltage. (C) 2000 John Wiley & Sons, Inc.