Preparation And Marine Anticorrosion And Antifouling Machanism Of Nano Zinc Oxide-Grapene Oxide-Waterborne Fluorinated Polyurethane Superamphiphobic Coating

Marine equipment and marine engineering facilities have been in the marine environment for a long time and face serious corrosion damage and biological fouling.Therefore,the development of marine anticorrosion and antifouling coating technology is of great significance to improve the service safety of marine engineering materials.The super-amphiphobic coating with"lotus leaf effect"can effectively delay the occurrence of corrosion and reduce biological adhesion fouling.In this paper,super-amphiphobic coating are prepared by combining low-surface-energy aqueous fluorine-containing polyurethanes with nano-zinc oxide/graphene oxide.The super-amphiphobic surface has the characteristics of low adhesion to water and marine organic substances.The antibacterial and anticorrosive effect of graphene oxide can obtain anticorrosive and antifouling functional coating.The structure of the composite and the super-amphiphobic coating were characterized,and the marine anti-corrosion performance and anti-biological adhesion performance of the nano ZnO-GO/PU super-amphiphobic coating were studied.The main research contents are as follows:(1)The nano ZnO was modified with perfluorooctyltriethoxysilane(PFOTS),the nano ZnO-GO composite with low surface energy was prepared by the hydrothermal method,and the nano ZnO-GO/PU super-amphiphobic coating was prepared by the two-step spray method.The structure,surface wettability and electrochemical corrosion of the coating were studied.The results show that the optimal dosage of PFOTS modifier is 15wt%,and a large amount of CF₂and CF₃groups are connected to the modified nano ZnO surface,resulting in a low surface energy nano ZnO-GO composite.The thickness of the nano ZnO-GO/PU super-amphiphobic coating is 119?m,and the surface has a micro/nano roughness structure.The coating has excellent mechanical stability,chemical stability,salt water corrosion resistance and salt spray corrosion resistance.Nano ZnO-GO/PU super-amphiphobic coating can effectively prevent the contact between the corrosive medium and the substrate,and delay the occurrence of the corrosion process.(2)PFOTS and KH-550 were used to modify the surface of nano ZnO and then compounded with graphene oxide.Nano ZnO-GO@PU super-amphiphobic coating was prepared on the surface of aluminum substrate by two-step spraying method.The structure,surface wettability,mechanical stability and anti-fouling performance of the coating were studied.The results show that when KH-550 and PFOTS are added with30wt%at a mass ratio of 1:3,the modification effect of nano ZnO is the best.The thickness of the nano ZnO-GO@PU super-amphiphobic coating is about 100?m,and the surface of the coating has a micro-nano rough structure.The nano ZnO-GO@PU super-amphiphobic coating exhibits excellent anti-chlorella adhesion properties,has a strong inhibitory effect on the adhesion and growth of microorganisms,and exhibits an obvious anti-biological adhesion effect.(3)The GO-ZnO composite was prepared by rapid precipitation method,the surface of the composite was modified by PFOTS,and the GO-ZnO@PU super-amphiphobic coating was prepared on the surface of the iron substrate by blending spraying method.The structure,surface wettability,mechanical stability and biofouling resistance of the coating were studied.The results show that the thickness of GO-ZnO@PU super-amphiphobic coating is about 60?m,the coating has good bending and impact resistance,and the adhesion of the coating reaches 5 B level.The GO-ZnO@PU super-amphiphobic coating exhibits good adhesion resistance to chlorella,has a strong inhibitory effect on the adhesion and growth of microorganisms,and has a good anti-biological adhesion effect.