The Preparation And Mechanical Properties Of Carbon Fiber/Inorganic Particle Co-reinforced Nylon6 Composite

Carbon Fiber(CF)reinforced thermoplastic resin matrix composites have attracted more and more attention because of their excellent mechanical properties,rapid prototyping,easy recovery,and less environmental hazards.Inorganic Particle(IP)has good mechanical properties,and excellent thermal stability.Various properties of resin matrix can be improved by the adding of IP,meanwhile enhancing the comprehensive properties of composites.On the one hand,in order to investigate the effect of IP on the mechanical properties of CF reinforced Polyamide 6(PA6)composites,mica(MICA),talc powder(TALC),and glass bead(GB)were respectively added into PA6 to prepare IP/PA6 composites.Effects of mixing mode,coupling agent content,particle size,particle content,and particle morphology on the mechanical properties and microstructure of IP/PA6 composites were studied.CF/IP/PA6 composites were prepared with IP(TALC or GB),PA6,and CF.Effects of particle content and morphology on the mechanical properties and microstructure of CF/IP/PA6 composites were discussed.Results were as follows:(1)The dispersion and compatibility of IP in matrix can be improved by coating silane coupling agent.When the particle size of MICA was about 7.5 ?m and the content of silane coupling agent was 1.5 wt.%,the best interfacial bonding between the particles and the matrix can be obtained,and the mechanical properties of the composites were optimal.(2)IP/PA6 composites prepared by melt extrusion were better than that prepared by mechanical stirring.The melt extrusion had a better improvement effect on the dispersion of IP and the mechanical properties of IP reinforced resin matrix composites than the mechanical stirring significantly(3)IP and PA6 mixed particles were prepared by melt extrusion,and CF/IP co-reinforced PA6 composites were prepared by laminated molding method.Effects of IP morphology and content on the properties of the composite were studied.Results showed that when the addition of MICA was 30 wt.%in the MICA/PA6 composites,the flexural strength was 104.3 MPa,the shear strength was 19.4 MPa,and the impact strength was 11.0 KJ/m2.When the addition of TALC was 10 wt.%or the content of GB was 15 wt.%,the mechanical properties of CF/IP/PA6 composites were optimal.The bending strength was 374.6 MPa or 404.4 MPa,in comparison with CF/PA6 composites,increased by 23.3%and 33.1%.The shear strength was 58.7 MPa or 66.7 MPa,in comparison with CF/PA6 composites,increased by 34.3%and 52.6%.The impact strength was 76.9 KJ/m2 or 86.5 KJ/m2,in comparison with CF/PA6 composites,increased by 86.7%and 110%.(4)The introduction of IP would induce stress concentration in the matrix,so the matrix around it can yield and absorbed a large amount of energy.Meanwhile,it can also hinder the propagation of cracks and thus lead to toughening effect,resulted in the improvement effects on the comprehensive mechanical properties of the composites.The enhancement effect of TALC on IP/PA6 composites was better than that of MICA because the modification effect of silane coupling agent on TALC was better than that of MICA.The mechanical properties of CF/IP/PA6 composites used GB were better than that used lamellar TALC.Because GB made the stress more uniform distribution,more easy to form craze,hole,crack deflection,pinning and other enhancement mechanisms.