wholly Aromatic Polyester (III) - Melt Processable Copolyester-

전방향족 폴리에스테르 (III) -용융 가공성 공중합체-

Wholly aromatic copolyesters from phenyl hydroquinone, 2,6-naphthalene dicarboxylic acid, ph-biphenyl dicarboxylic acid and l-acetoxybenzoic acid were synthesized by melt polycon- densation. Their properties were investigated by using DSC, polarizing microscope, TGA, and RDS. These copolyesters showed melt transitions at the temperature below 300℃ to give a processable nematic melt. The Tg's were closely related to the composition of the copolyesters. When the ratio of oxybenzoyl unit was increased the Tg was decreased. The fiber structures and mechanical properties of the copolyesters were observed by using SEM, X-ray diffractomer and Instron. The fibers had high orientation and good mechanical properties such as tensile strength min. 170kg/mm2 and modulus 12000kg/mm2.