synthesis and characterization of side chain liquid crystalline polysiloxanes containing benzyl ether linking units

Side chain liquid crystalline polysiloxanes containing benzyl ether linking units were synthesized by the hydrosilylation of poly(methylhydrosiloxane) with a series of 4-(4-alkoxybenzyloxy)-4′-allyloxybiphenyl monomers [4-(4-methoxybenzyloxy)-4′-allyloxybiphenyl (M₁), 4-(4-ethoxybenzyloxy)-4′-allyloxybiphenyl (M₂), 4-(4-propoxybenzyloxy)-4′-allyloxybiphenyl (M₃), 4-(4-butoxybenzyloxy)-4′-allyloxybiphenyl (M₄), 4-(4-pentoxybenzyloxy)-4′-allyloxybiphenyl (M₅), 4-benzyloxy-4′-allyloxybiphenyl (M₆)]. The phase behavior of monomeric and polymeric liquid crystals was characterized by differential scanning calorimetry and optical polarization microscopy where the groups are ranged from methoxy to pentoxy. Both the monomeric and polymeric liquid crystals exhibit liquid crystal behaviors.