Study on the preparation and performance of an electrically controlled dimming film with wide working temperature range

Polymer dispersed liquid crystal (PDLC) films have shown potential applications in various fields such as curtain walls, indoor partitions and smart windows due to their large-area and convenient manufacturing ability. However, the narrow working temperature range limits their outdoor applications, especially in automobiles. In this study, methods to improve the performances of PDLC films at high and low temperatures were explored. Liquid crystals (LCs) with wide temperature range were used and different polymerizable monomers and cross-linking agents matching the LCs were investigated. Results show that the prepared PDLC film has a better contrast ratio of 48 at a high temperature of 90 °C, and fast on-state and off-state response times of 74 ms and 895 ms at −20 °C, respectively, when using hexyl acrylate as monomer and 1,4-butanediol diacrylate as crosslinking agent. This research could promote the application of PDLC films to outdoor scenes like smart windows for automobiles.