Effects of Multi-Fluorinated Liquid Crystals with High Refractive Index on the Electro-Optical Properties of Polymer-Dispersed Liquid Crystals

Polymer-dispersed liquid crystals (PDLCs) are composite materials, in which LCs are dispersed in the form of microdroplets in a polymer matrix. As a composite material, its electro-optical properties are affected by many factors such as molecular structure, composition, and the microstructure of the LCs and polymers. In this work, PDLC films were prepared based on the thiol-ene click reaction, and effects of refractive indexes of polymers and LCs on their electro-optical properties were studied. The refractive indexes of the polymer matrix are adjusted by controlling the content of sulfur element, and those of the LCs are adjusted by adding multi-fluorinated LCs with high refractive index. By regulating the refractive indexes of the polymer matrix and LCs, the maximum transmittance of the film is raised and the viewing angle of the film is also extended. This work could afford some ideas for the directional regulation of the viewing angles and the electro-optical properties of the PDLC film.