Preparation And Properties Of Graphene/Silica Fume Waterborne Epoxy Resin Anticorrosion Coating

The two-dimensional structure of graphene and silica fume is widely used in anti-corrosion fields because of their large specific surface area and good hydrophobicity,which also the reason why graphene and silica fume difficult to disperse in the resin matrix and easy to agglomerate,limited their application in polymer-based anti-corrosion coatings.In this paper,the surface modification method is used to modify graphene and silica fume to improve the dispersibility of the surface,thereby improving the anti-corrosion performance of polymer matrix composites.Firstly,graphene was functionally modified by the non-covalent methods to improve its dispersibility in waterborne epoxy resin,then the effect of functionalized graphene on the corrosion resistance of composite coatings was explored.Due to the conductive properties of graphene,the content in the resin substance is limited.The last chapter explores the effect of silane coupling agent modified silica fume on corrosion resistance of waterborne epoxy resin composite coatings.The main contents of the full text are as follows:（1）Preparation of PBI/GR/WEP coating with excellent corrosion resistance and friction resistance.Highly oriented PBI/GR/WEP coatings were prepared byπ-πstacking method and spin coating method.When the ratio of the PBI and GR is 1:1,the impedance value reaches about 10⁹ωcm²,Compared with the waterborne epoxy coating（10⁶ωcm²）,the resistance value of PBI_0.5%/GR_0.5%/WEP coating is increased by 3 orders of magnitude.The friction coefficient decreased by 48%,the wear resistance increased 87.6%.The results showed that:PBI_0.5%/GR_0.5%/WEP coatings with good corrosion and wear resistance.（2）Preparation of O-g-KH570/GR/WEP anti-corrosion composite coating.The O-g-KH570/GR/WEP composite coating was prepared by KH570 modified okra polysaccharide（O-g-KH570）as a graphene dispersant.When the addition amount of Og-KH570 reaches 3%,the dispersibility of graphene is the best,and the impedance reaches 2.1×10⁷Ωcm²,after immersing in the 3.5%Na Cl solution for 10 days,after immersing in the 3.5%Na Cl solution for 10 days,it still showed the corrosion efficiency of 72.4%,and the corrosion rate was 67.1nm/year,which improved the corrosion resistance.（3）Preparation of KH550 modified silica fume anti-corrosion composite coating.The SF-K/WEP composite coatings was prepared by combing microsilica powder modified silica fume and spin coating method,explored the influence of SF-K content on the anti-corrosion performance of the coating.When the addition amount of SF-K reaches 2%,the impedance of the SF-K_2%/WEP composite coating reaches 8.5×10⁷Ωcm²,and the corrosion rate is 0.9 nm/year After soaking in 3.5%Na Cl solution for 10days,it still shows 99.9%corrosion efficiency.The increase in the number of micro-silica flakes effectively improves the corrosion resistance.