SYNTHESIS AND CHARACTERIZATION OF NEW SIDE-CHAIN LIQUID-CRYSTALLINE POLYMERS BASED ON POLY(DIPROPARGYLAMINE) MAIN-CHAIN

Abstract

A new thermotropic side-chain liquid crystalline polymers based on poly (dipropargylamine) backbone were prepared by metathesis polymerization with transition metal catalysts. It was found that the MoCl5-EtAlCl(2) catalyst system were very effective for the cyclopolymerization of presently investigated monomers. Resulting polymers were soluble in common organic solvents such as THF, chloroform, etc. The number-average molecular weight (($) over bar Mn) values of the polymers were in the range of 6.49 x 10(3) - 11.6 x 10(3), relative to polystyrene standard by GPC. Thermal properties of the monomers and the polymers synthesized were examined by differential scanning calorimetry (DSC) and cross-polarized optical microscopy. Both monomer and polymer displayed enantiotropic liquid crystallinity showing the reversible phase transition.