Synthesis and characterization of side-chain liquid crystalline polysiloxanes

Side chain liquid crystalline polysiloxanes containing biphenyl and benzyl ether mesogen were synthesized by the hydrosilation of poly (methylhydrosiloxane) with 4-(4-allyloxybenzyloxy)-4′- methoxybiphenyl (M₁), 4-(4-allyloxybenzyloxy)-4′-ethoxybiphenyl (M₂), 4-(4-allyloxybenzyloxy)-4′- propoxybiphenyl (M₃), 4-(4-allyloxybenzyloxy)-4′-butoxybiphenyl (M₄), 4-(4-allyloxybenzyloxy)-4′- pentyloxybiphenyl (M₅). The phase behavior of monomeric and polymeric liquid crystals was characterized by differential scanning calorimetry and optical polarization microscopy. Both the monomeric and polymeric liquid crystals exhibit liquid crystal behaviors.