Synthesis and characterization of siloxane contained liquid crystalline polymers with two symmetric mesogens

New thermotropic siloxane contained liquid crystalline polymers with two symmetric mesogens were prepared by hydrosilation with Rh(PPh(3))(3)Cl catalyst. It was found that Rh(PPh(3))(3)Cl catalyst was effective for low molecular weight polymerization. The resulting polymers exhibited good solubility in organic solvents such as tetrahydrofuran(THF), chloroform, and so on. The structures of the monomer and polymers were confirmed by IR, H-1 and C-13 NMR spectra The number average molecular weight(<(Mn)over bar>) values of the polymers were in the range of 2000 similar to 6000. Thermal properties of the monomers and the polymers were analyzed by differential scanning calorimetry(DSC), and polarized optical microscopy. Monomers did not show liquid crystalline phase but the polymers exhibited nematic phases.