Continuous Carbon Fiber Reinforced Poly (Phthalazinone Ether Nitrile Ketone)composites And Their Compatibilizer

On the basis of preserving the excellent mechanical properties and heat resistance of traditional thermosetting composites,continuous carbon fiber reinforced high performance thermoplastic?CFRTP?composites with its unique,simple processing technology,high toughness,high impact,reusable recycling and environmentally friendly,get more and more widely application in the field of advanced market and civil applications.Poly?phthalazinone ether nitrile ketone??PPENK?is a high performance resin,developed by our group,possessing excellent mechanical properties,heat resistance and good solubility in some organic solvents.Thus the solution processing can be adopted to prepare fiber reinforced composites using PPENK.The purpose of this paper is to introduce a kind of compatibilizer to improve the melt flow properties of PPENK and the interfacial properties between resin and fiber.Here,the compatibilizer with fluorene-9-bisphenol and pendent ester group?PFEK-E?is synthesized and characterized by ¹H NMR and FT-IR.The solubility and GPC test of compatibilizer show that the molecular weight of PFEK-E is 17400,which is soluble in non-proton polar solvent.The DSC,TGA and rheological property test of PFEK-E/PPENK show that the Tg is 215?,the temperature of 5%mass loss in N₂ is 478?,and the heat resistance and compatibility of the compatibilizer can match with PPENK.Besides,PFEK-E can effectively reduce the melt viscosity of PPENK,improve the secondary infiltration effects of carbon fibers and improve processing performance of CF/PENK composites.The optimal process parameters of the molding temperature?380??,molding pressure?12MPa?,molding time?30min?and the resin adhesive solution concentration?14%?are determining by designing orthogonal experiments.It's showed that when the content of PFEK-E is 10%,the mechanical properties and interface strength of composites are most excellent.Under the condition of room temperature in the dry state,the flexural strength,the flexural modulus and the short beam shear strength of CF/10%PFEK-E/PPENK composites are 1844MPa,148GPa and 84.3MPa respectively.Under the condition of 200?in the dry state,the flexural strength,the flexural modulus and the short beam shear strength of CF/10%PFEK-E/PPENK composites are 1250MPa,127GPa and 56.6MPa respectively.Under the condition of room temperature in the wet state,the retaining rate of the flexural strength and the short beam shear strength of CF/10%PFEK-E/PPENK composites are 90%and 99%respectively.Besides,CF/10%PFEK-E/PPENK composites exhibit good moisture and heat resistance.Under the condition of 200?in the wet state,the retaining rate of the flexural strength and the short beam shear strength are 59%and 60%respectively.The DMA test shows that CF/10%PFEK-E/PPENK composites have excellent heat resistance and high temperature mechanical properties and can be used under the environment of 250?for a long time.The results of ultrasonic C scan show that the internal defects of composites are few and composites can give full play to the synergistic effect of resin matrix and carbon fiber.The results of SEM show that the addition of compatilizer can effectively improve the infiltration effect of PPENK resin matrix on carbon fiber,and improve the interfacial bonding strength between fiber and resin.