A 4,4＇-（ hexafluoroisopropylidene ） diphthalic anhydride- bis [ 4-（ 4-aminophenoxy ） phenyl J sulfone （ 6FDA-BAPS） polyamic acid （PAA） was synthesized by using 6FDA and BAPS as reactive monomers and N-methyl-2-pyrrolidone（NMP） as a solvent. The PAA solution was prepared into membranes by casting technology and was also prepared into PAAhollow fiber membranes by dry wet spinning process. The PAA membranes and PAA hollow fiber membranes were exposed tothe high-temperature thermal cyclization at about 300 ℃ to produce a 6FDA-BAPS polyimide （PI） membranes and hollow fibermembranes. The structure and properties of 6FDA-BAPS PI products were studied. The results showed that the obtained 6FDA-BAPS PI was the target product which was of fairly good solubility in NMP, dimethylaeetamide and tetrahydrofuran ;the 6FDA-BAPS PI possessed the dense outer layer and the loose and porous support layer;the hollow fiber membranes had the 5 % weightloss temperature of 511 ℃ and breaking strength 26.5 MPa, indicating relatively high thermal and mechanical properties.
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