Through simple chemical reactions, 3-aminopropyl triethoxysilane and 3-glycidyl ether oxypropyl trimethoxysilane have been successfully grafted onto graphene oxide to prepare composite of a sandwich structure. The two surface modifiers make it easier for the graphene oxide to form chemical bonds with epoxy resin/polyamine. Through electron microscope and visibleinfrared full-band transmittance tests it is found that the graphene oxide treated by the modifier can evenly disperse in the resin system. Compared with the pure epoxy amine resin coating, the water vapor transmittance of the GO-APTES/Resin coating is reduced by 30%. A "labyrinth effect" is formed, which is a good barrier against water vapor. Moreover, the anti-corrosion mechanism of the composite coating is studied by Bode and Nyquist spectra. The shielding of the coating against the corrosive medium is enhanced after adding modified graphene oxide, and the ability of the corrosive medium to penetrate the coating is reduced. Therefore, the coating is better attached to the metal and the area of electrochemical corrosion is smaller, having a better corrosion protection ability. Neutral salt spray test shows that the coating surface will not fall off or present blister after 7000 hours.
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