Synthesis And Study On The Properties Of The Silicon-containing Epoxy Curing Agent

Epoxy resin has excellent adhesive property, corrosion resistance, and good mechanical properties. But its impact strength and thermo properties can satisfy people when used in some certain field. It is the same of the surface property. This article prepared a silicon aromatic amine epoxy curing agent (SAACA) which synthetized by the reactive monomer hydroxy silicone oil (HTPDMS), toluene diisocyanate (TDI) and diethylamine (DEA). Molecular structure was analysis by FTIR. A contract curing that was polyether aromatic amine epoxy curing agent (PEAACA) was synthesized in the purpose of analyzing the influence of the organosilane, which use polyether glycol instead of HTPDMS. Test sample was prepared for both of the synthesis curing and the mixed curing. TG、 DTG, FTIR、 SEM were used to analysis the molecular structural and microstructural. The mechanical property and heat deflection temperature were tested. And surface properties of the system were analyzed at last. The research provides science basic for the application of this kind of EP curing agent.The curing processing of EP/SAACA、EP/PEAACA and EP/SAACA/DDM system was studied by non-isotherm differential scanning calorimetry (DSC). And apparent activation energy and reaction order of curing reaction were calculated, and obtained kinetic equation of curing reaction. The activation energy of EP/SAACA curing system is57.07kJ/mol, the curing reaction order is0.940; EP/PEAACA system is E2=45.38kJ/mol, n2=0.9066; EP/SAACA/DDM is E3=75.17kJ/mol, n2=0.9066. And by analyzing the three curing system of the epoxy resin we found that the long molecular chain can lower the activation energy, and the polyether chain is better than the organosilane chain. But the reaction rate is rising slowly than the organosilane chain. The curing condition which is95℃for3h,125℃for3h, which is determine by the results and the curing property.The mechanics test shows the property of the resin that cured by SAACA is the same as normal EP. Flexural strength of the curing resin is72.1MPa, the impact strength is9.37kJ/m2, and thermal deformation temperature is92.4℃. But the mixed system EP/SAACA/DDM has a good mechanical property. The best flexural strength of the tested sample is107.5MPa, the impact strength is23.68kJ/m2, the compressive strength is107.5MPa, and thermal deformation temperature is152.3℃. The property is changed when the content of the synthesis curing is changed in the curing system. It is found that the impact strength is improved133%when used the synthesis curing. This is proved that the synthesis curing can improve the resin’s toughness efficiently. The SEM picture shows that the fracture mechanism of the EP/SAACA system is changed from the brittle fracture to the gliding fracture; EP/SAACA/DDM system is gliding fracture which the EP/DDM system is brittle fracture. Toughening mechanisms may be the "crack-pinning" theory.Contact angle test shows that the angle is about100°when use SAACA more than10phr. The resin surface becomes hydrophobic. And when synthesis curing was used for70phr., the contact angle has an increase to118°. This sample is the best series of the EP/SAACA system. That can be used in the certain field where needed hydrophobic matrix.