Study Of Bismaleimide Resin System And Carbon Fiber Composite Interlayer Toughened Synergistic Ally With Micro-nanometer Particles

After the first generation based on single-phase resin and the second generation toughed with complex-phase resin,the interlaminar-toughened technique has become the trendency to improve the tougheness of carbon fiber composites.It is also called the third generation.The region between layers will used as a controllable target to be optimized.In order to satisfy the prepregs process requirements,this paper present a method by using multiphase particles as tough agents to prepare resin system and its prepreg of carbon fiber.The unification of toughness and processing adaptability meet well.1.BD resin system was prepared using Diallyl bisphenol A(DABPA)as a chain extender of bismaleimide(BMI).The mechanism of cure reaction,cure process and blend process were studied.The cure reaction includes two steps,the first step is "Ene addition reaction",including few self-polymerization of BMI;the second step is "Diels-Alder addition reaction".Initial cure temperature at 160? is benefit for "Ene addition reaction",and can keep the self-polymerization of BMI monomer under control.So the final cure process is determined.Low viscosity resin system was prepared by"multiphase-composites" blend process,which changes high viscosity and low stickiness of conventional dissolution at high temperature.2.PEI/BD resin system were prepared using poly(ether imide)micro-particles(PEI).Thermal properties,mechanical properties and toughness mechanism were studied.Compared to pure BD,PEI has less influence on Tg,fracture toughness improved at 50%,impact strength improved 38%,and fracture surface showed transformation from brittleness to toughness,which indicated PEI has good toughening effect.3.CSR/BD resin system were prepared using core-shell nanoparticle(CSR).Thermal properties,mechanical properties and toughness mechanism were studied.Compared to pure BD,CSR has less influence on Tg,fracture toughness improved at 62%,impact strength improved 38%,and fracture surface showed a lot of cavity,which indicated obvious cavitation toughening effect.4.CSR/PEI/BD resin system were prepared using micro-nanometer particle.Viscosity temperature characteristics,thermal properties,mechanical properties and toughness mechanism were studied.Compared to pure BD,micro-nanometer particle maintained good manufacturability and heat resistance,fracture toughness improved at 79%,impact strength improved 50%,and achieved the balance of toughness and rigidity.CSR/PEI/BD resin system had dual toughening mechanism of PEI deformation and CSR cavitation.5.Interfacial strength of monofilament Composites improved at 37%,Prepreg were prepared based on CSR/PEI/BD resin system.Interlaminar shear strength improved at 24%,flexible strength improved at 23%,and GIC improved at 87%.The toughening mechanism was discussed and the mechanism model of synergistic interlayer toughening is established.