Study On Marine Environmental Properties Of Carbon Fiber/Modified Epoxyy Vinyl Ester Resin Composites Materials

In the field of ship and ocean engineering,composite materials are booming,with the development of resin matrix carbon fiber reinforced composite material,with its excellent performance of the Marine environment,can meet the shipping industry on the material of low cost,high performance,and to meet the requirements of automation and integration,but at the same time,the VE resin and its performance of carbon fiber is the combination of interface cross,The toughness of the resin matrix itself is not high,and the interface bonding performance is poor,which matters the all properties of the composites,so it is important to conduct in-depth modification research.Epoxy vinyl ester resin was modified in combination of IPN polymer toughening and rigid particle toughening.The method of interpenetrating network is mainly to enhance the interface of the composite material,so that it can not only toughen,but also retain and even improve the mechanical properties to the greatest extent.This method is better than the rubber body toughening in terms of mechanical properties.The rigid particles doped into resin can improve the resin's modulus and strength,and improve the aging and corrosion resistance of the resin in the Marine environment;Therefore,the toughening agents selected in this paper are respectively epoxy resin(TDE-85)and nano-SiO₂.The formula of nano-SiO₂ modified resin was finally compared,and 1%addition was chosen for the preparation of subsequent composites.At this time,the tensile strength,compression strength and bending strength of the resin casting body were 72MPa,109MPa and 151MPa.The compression modulus was3.18GPa,and the fracture elongation was 2.8%.The performance of TDE85 IPNS system will appear a peak with the increase of epoxy resin content.The strength increased obviously,and the improvement rate was higher than that of nano particle modification.In this paper,the formula with 23%TDE85 resin content was chosen as the optimal formula.At this time,the comprehensive performance of the mixed resin system was the best.The tensile strength,compression strength and bending strength of the resin casting body were 83.22MPa,124MPa and 143.2MPa,the compression modulus was 3.68GPa,and the elongation break was 4.12%.Scanning electron microscopy(SEM)was used to analyze the fracture of the resin.It was found that the TDE85 modified resin showed dimples and the nano-SiO₂modified resin showed silver striations,both of which showed ductile fracture.The seawater immersion experiment on the resin castable finally found that the water absorption rate of the resin modified by TDE85 was significantly reduced,while the water absorption rate of the resin modified by nanoparticles was the lowest.The addition of nano-SiO₂ reduced the water absorption rate of the resin,and could prevent the seawater from entering the resin and eroding the internal structure of the resin.Finally,the composite laminates were prepared by using the above resin formula and process.The tensile strength of the laminates prepared by nano-SiO₂ modified resin is 553.3MPa,which increases by 10.4%.The tensile strength of TDE85 modified resin laminates is 600MPa,which is increased by19.7%.The compressive strength of nano-SiO₂ modified laminates is 249MPa,increased by 38.3%,and the compressive strength of TDE85 modified laminates is 370MPa,increased by 105.6%.The flexural strength of nano-SiO₂ modified laminates is 519MPa,increased by 12.8%;the flexural strength of TDE85modified laminates is 692MPa,increased by 50.4%;the interlaminar shear strength of nano-SiO₂modified laminates is 38MPa,increased by 35.7%.The interlaminar shear strength of TDE85 modified laminates is 47MPa,which increases by 67.9%.Then,the seawater immersion experiment of composite laminates was carried out under the condition of 60?for 25 days and 50 days respectively.The aging test of composite laminates was carried out.Finally,the conclusion was reached that,among the two modification methods,the TDE85 modified laminates had the highest mechanical properties but lower strength retention rate,and the strength of nano-SiO₂ was higher than that of unmodified laminates.Moreover,the strength retention rate is higher than that of TDE85modified resin.Scanning electron microscopy(SEM)was used to analyze the composite specimens.,after modified by TDE85,the binding property is better,the interfacial strength is higher,and the fiber pullout is reduced.However,the laminates modified by nanoparticles mainly improve the overall properties of the laminates by strengthening the resin...