Syhthesis and Properties of Side-Chain Liquid-Crystalline Polysiloxanes Exhibiting Cholesteric Platelet Texture

Side-chain liquid-crystalline polysiloxanes(SCLCP) were synthesized through hydrosilylation,grafting(trans,trans)-4-propyl-4'-propenyl-bicyclohexane on the flexible main chain of polysiloxane,and the yield was 82.5%.The molecular structures of SCLCP were confirmed by Fourier Transform Infrared spectroscopy(FT-IR) and Hydrogen-Nuclear Magnetic Resonance spectra(¹H-NMR).Liquidcrystal phase and liquid crystal behavior of SCLCP were analyzed by Polarizing Optical Microscopy (POM) and X-Ray Diffraction(XRD).Phase transition temperature and thermal properties of SCLCP were analyzed by Differential Scanning Calorimetry(DSC).Results show that SCLCP exhibits cholesteric platelet texture,and the mesomorphic region is 57.33 K,which is higer than that of monomer.