Abstract:Poly(trifluorochloroethylene) (PCTFE) is one of the most important thermoplastic fluororesins. Due to its regular molecular structure and large crystal size, the products are usually brittle, sensitive to notches and prone to stress cracking. In this paper, PCTFE with different molecular weight were blended to improve its cracking resistance, and the toughness is enhanced, without the addition of other functional aids. The dynamic rheology results of the PCTFE blends show that PCTFE with different molecular weight has good compatibility. When the PCTFE content of the higher molecular weight (that is, PCTFE-M) increases, the entanglement of the molecular chains is enhanced, resulting in the restriction of the molecular mobility. The results of polarized optical microscope (POM) and differential scanning calorimetry (DSC) exhibit that the crystal size and the crystallinity of PCTFE are decreased after the addition of PCTFE-M. When the content of PCTFE-M is 30%, the impact strength of the blends is 140% higher than that of unmodified PCTFE, exhibiting typical ductile fracture behavior.