Study on Synthesis and Characterization of Ferroelectric Side Chain Liquid Crystalline Polymers

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1) Various liquid crystalline polymethacrylates with terminal chains were schematically synthesized, and effects of terminal chain lengths for their phase transitions and smectic layer structures were examined.In the liquid crystalline polymethacrylates (SCLCPMs) having terminal alkoxy chains in the mesogenic pendant group, SCLCPMs form smectic C phases with polytype layer structures when the length (m) of the terminal alkoxy group is longer than butoxy group (m=4). In SCLCPMs having the terminal chains of m=4, 5, and 6, tilt angles are 60-62ﾟ, and in the case of m=7 and 8, the tilt angle is 50ﾟ. however, Chiral SCLCPM having s-(-)-2-methylbutoxy terminal group (corresponding to the length of m=4) forms a tilted monolayer structure with the tilt angle of 42ﾟ in a chiral smectic C^* phase.These results conclude that the layer structure and tilt angle can be con-trolled through the length and structure of the terminal chain.2) Novel ferroelectric side chain liquid crystalline polymers were prepared and their spontaneous polarizations were examined.A chiral liquid crystalline polytartrate which have chiral groups in a polymer backbone forms a chiral smectic C^* phase and has a large spontaneous polarization (PS) of 5 mc/m^2. A chiral liquid crystalline polymethacrylate having a chiral group in a spacer unit also exhibit a chiral smectic C^* phase with Ps of 1.2 mC/m^2A chiral group can be also introduced in the polymer skeleton through copolymerization. A chiral liquid crystalline copolymethacrylate prepared by copolymerization of chiral nonmesomorphic and achiral mesogenic methacrylates forms a chiral smectic C^* phase.