사슬연장제로서 3관능성 공단량체가 도입된 폴리(파라-페닐렌 벤조비스옥사졸) 섬유의 제조와 특성분석

Abstract

A series of poly(p-phenylene benzobisoxazole) (PBO)-based copolymers containing a trifunctional moiety in theirbackbones were prepared via polymerization of 4,6-diaminoresorcinol dihydrochloride (DAR) with terephthaloyl chloride(TPC) and 1,3,5-benzenetricarbonyl trichloride (BTC) in poly(phosphoric acid) (PPA). The concentration of trifunctionalBTC comonomer was controlled during polymerization to be 0.0-2.0 mol% of difunctional TPC concentration. The inherentviscosity and associated average molecular weight of PBO copolymers with different BTC contents were evaluated by usingsolution viscometry and the Mark-Houwink equation, respectively. In addition, single fibers based on neat PBO and its copolymerswere prepared by in situ dry-jet wet spinning of anisotropic liquid crystalline polymerization products in PPA dopes. The molecular structure and morphology of the as-spun fibers were determined. The effects of BTC content on the thermalstability and tensile mechanical properties of the as-spun fibers were also investigated.