The present invention belongs to the technical field of high-performance material synthesis, and specifically relates to a poly(p-phenylene benzobisoxazole) (PBO) copolymer and a preparation method of compression performance-enhanced PBO fibers. The preparation method comprises the following steps: subjecting 4,6-diaminoresorcinol dihydrochloride, terephthalic acid and 1,3,5-tris(4-carboxyphenyl)benzene to a gradient temperature programmed polycondensation reaction in a polyphosphoric acid system to obtain a PBO prepolymer solution; completing high-degree polymerization of the PBO prepolymer solution in a twin-screw extruder to obtain a poly(p-phenylene benzobisoxazole) copolymer; then performing fiber formation via dry-jet wet spinning, and subjecting the formed fibers to two-stage water washing, primary drying, oiling, secondary drying and winding to obtain PBO fibers. Through the addition of the rigid crosslinking monomer, the present invention can retain the excellent properties of poly(p-phenylene benzobisoxazole), endow the prepared PBO fibers with high tensile strength, high modulus and high heat resistance, and significantly improve their compression performance, providing a new method for the molding and processing of poly(p-phenylene benzobisoxazole).
Country Code: CN
Application Number: CN202410497552.1
