Effects of Molecular Structure on the Properties of Terminally Cyano-Substituted Side Chain Liquid Crystalline Polysiloxanes

Abstract

The synthesis and properties of a range of liquid crystalline side chain polysiloxanes are described. The effects of changes in chemical structure, such as lateral substitution, on the properties of these materials are discussed, and comparisons are made with the effects of similar structural changes in low molar mass materials. By selecting suitable side chains for homopolymers and copolymers, room temperature smectic, nematic and cholesteric (chiral nematic) polysiloxanes of positive dielectric anisotropy have been prepared, including the first example of a nematic siloxane homopolymer containing a cyano-group.