Comparative study of dielectric and electro-optical properties of pure and polymer ferroelectric liquid crystal composites

The ferroelectric liquid crystals (FLCs) displays normally suffer from less contrast ratio and vision angle. To produce high optical contrast and colors in FLC displays, Guest-host mode is widely used. Addition of a small amount of polymer in the pure FLC results in considerable change in its dielectric and electro-optical properties. In the present paper we have investigated the effect of adding polymer (PMMA) on the FLC material (Felix 17/100). Polymer doped FLC composites (FLCPC) has been prepared by the dispersion of 1% wt/wt concentration of polymer in pure FLC. Planar aligned cells have been used to study dielectric and electro-optical properties in SmC* phase of both the samples i.e. pure FLC and FLCPC. Considerable change in various properties like spontaneous polarization, anchoring parameters, Goldstone mode relaxation time and relaxation strength have been noticed for both the samples. These changes have been explained by considering polymer network formed in the FLC matrix.