【摘要】 研究了四氟乙烯和六氟丙烯共聚物的熔融指数,抗张强度和耐应力开裂之间,以及端基和热稳定性之间的关系。发现:（1）在一定的共聚物组成和分子量分布情形下,共聚物的熔融指数和抗张强度的关系可表示为经验式:F=350—18.3（M_I）;（2）熔融指数大于4的共聚物不耐热应力开裂;（3）共聚物经380℃热处理,其端基转变为-CF=CF₂后,已具有挤出成型所要求的热稳定性。更多还原

【Abstract】 The relationship between the melt index, the tensile strength and the stress-crack resistance, and that between the end-group structure and thermal stability of copo-lymer of tetrafluoroethylene and hexafluoropropylene have been studied. It was shown that: (1) Within a definite copolymer composition and molecular weight distribution, the relationship between the melt index and the tensile strength of the copolymer can be expressed by the empirical equation: F= 350-18.3 (MI); (2) The copolymer with melt index larger than 4 is Poor in thermal stress-cracking properties; (3) When the end-group was converted into - CF = CF: by heat treatment at 380° C, the copolymer was shown to be stable thermally during extrusion processing.更多还原