Preparation Of Epoxy Resin Anticorrosive Coating By Amino Modified Graphene Oxide

As an important derivative of graphene,graphene oxide has large specific surface area and super strong shielding effect.Adding graphene oxide to epoxy resin coating to improve the corrosion resistance of epoxy resin coating is a new research direction.Due to the strong agglomeration of graphene oxide,the dispersion of graphene oxide in epoxy resin coating is not good.For this reason,urea and melamine modified graphene oxide were prepared respectively.The influence of reaction temperature and modifier mass fraction on the structure of modified graphene oxide was studied.The electrochemical properties and corrosion resistance of urea and melamine modified graphene oxide on epoxy resin coatings were evaluated.The structures of urea and melamine modified graphene oxide were analyzed by XRD,Raman,FT-IR,TEM and AFM.The corrosion resistance of pure epoxy resin coating（EP）,graphene oxide and epoxy resin composite coating（GO/EP）,urea modified graphene oxide epoxy composite coating（NGO）and melamine modified graphene oxide epoxy composite coating（MGO/EP）were tested by using electrochemical workstation and salt spray corrosion test.The experimental study on the effect of reaction temperature on the structure of modified graphene oxide shows when the reaction temperature is 95°C,urea has the best effect on the modification of graphene oxide.The effect of modifier mass fraction（1:5;2:5;3:5;4:5;5:5）on the structure of modified graphene oxide was studied at the optimum reaction temperature.The experimental results showed that when the mass ratio of urea and graphene oxide is 1:5,urea has the best effect on the modification of graphene oxide.The experimental study on the effect of reaction temperature（60°C,70°C,80°C and100°C）on the structure of melamine-modified graphene oxide shows when the reaction temperature is 80°C,melamine had the best effect on the modification of graphene oxide.The effect of modifier mass fraction（1:5;2:5;3:5;4:5;5:5）on the structure of modified graphene oxide was studied at the optimum reaction temperature.The experimental results showed that when the mass ratio of urea and graphene oxide is 1:5,melamine has the best effect on the modification of graphene oxide.The comparison of salt spray corrosion test and electrochemical experiment of NGO/EP,GO/EP and EP coatings shows that when the reaction temperature is 95°C,the modifier mass fraction is 1:5 and the modified graphene oxide is 0.1%,the corrosion current density and polarization resistance of the NGO/EP coating were 1.50×10^-11A/cm²and 8.98×10¹¹Ω,respectively.The 300-hour salt spray corrosion test showed that the NGO/EP coating had the best corrosion resistance.The comparison of salt spray corrosion test and electrochemical experiment of MGO/EP,GO/EP and EP coatings shows that when the reaction temperature is 80°C,the modifier mass fraction is 1:5 and the modified graphene oxide is 0.3%,the corrosion current density and polarization resistance of the MGO/EP coating were 2.74×10^-11A/cm² and 5.08×10¹¹Ω,respectively.The 300-hour salt spray corrosion test showed that the MGO/EP coating had the best corrosion resistance.The electrochemical performance and salt spray corrosion performance test of urea-modified graphene oxide epoxy coating and melamine modified graphene oxide epoxy coating showed that the reaction temperature was 80°C,the modifier mass fraction was 1:5 and the amount of modified graphene oxide added is 0.3%,the melamine modified graphene oxide epoxy resin coating has better corrosion resistance.