Thermotropic liquid crystalline polymers with two different mesogenic groups of smectic and nematic state were prepared in the form of homopolymer and block copolymer. The monomers were 4,4'-dihydroxy- 1,10-diphenoxy decane and 1,10 -bis(4-hydroxyhenzoyloxy) decane, which had identical number of methylene unit as the flexible spacer. The homopolymers having different molecular weights were synthesized by varying the stochiometric ratio of the monomer and terephthaloyl dichloride. In order to synthesize the block copolymer, hydroxyl terminated oligomer having nematic monomer unit and acid chloride terminated oligomer having smectic monomer unit were reacted. Blends were prepared by mixing the block copolymer and homopolymer using solution/precipitation method. The transition temperatures of blends were determined by the heating thermograms of the differential scanning calorimeter (DSC) and the observation on the polarizing microscope. From these results, the phase diagram was established with weight ratio of the block copolymer and homopolymer. Also, degree of crystallinity of the blends were investigated by using wide angle X-ray diffraction (WAXD) method.
