Characterization of PVA Dispersed Cholesteric Liquid Crystal; Investigation of Optical and Dielectric Properties

Abstract

Composite materials by dispersing polymer into cholesteric liquid crystals (CLC) are very useful to minimise many drawbacks of pure liquid crystals like threshold voltage, contrast ratio, stability etc. These materials are used for many applications like light shutters, smart windows in addition to display. The present paper is an attempt to study and compare optical and electrical properties of pure and composite CLC. The polyvinyl alcohol of different concentrations was dispersed to cholesteryl palmitate by chemical method. The study of optical properties was performed by polarizing optical microscopy (POM) and fabry perot scattering studies (FPSS) whereas the dielectric properties were studied by impedance analyser. It was found that the CLC shows more stability and improved performance after dispersing polyvinyl alcohol which may provide new opportunity for potential application of these materials.