High‐performance thermoplastic toughener for bismaleimide resin: Feature application of reactive polyarylether ketone bearing propenyl group

Abstract The introduction of reactive groups into thermoplastic tougheners can overcome the phase separation problem between conventional thermoplastic resins and thermosetting resins, thereby improving the compatibility between the two phases and significantly enhancing the materials' toughness. In this study, a series of polyaryletherketone (RPEK‐C) copolymers with a molecular backbone containing reactive propenyl and controllable groups are prepared. Through blending different amounts and different reaction group contents of thermoplastic resins into the N,N'‐（4,4'‐methylenediphenyl) dimaleimide(BDM)/2,2′‐diallylbisphenol A (DABPA) system, all of them show a homogeneous phase instead of separation phase after curing, and the impact toughness is improved to different degrees. When RPEK‐C‐10 with 7.5 phr is added, the impact strength of the toughened BDM/DABPA can be increased up to 172.5%. Compared with the nonactive PEK‐C, active groups of RPEK‐C can react with BDM, playing a role in “anchoring” the thermoplastic molecular chains. The toughening mechanism of BDM/DABPA with RPEK‐C participating is discussed. This study shows that polyaryletherketones with functional active group have great potential application in high‐end toughening fields.