Research On The Envirnmental Adaptability Of Micro-nano Antibacterial And Anticorrosion Coating

The breeding of bacteria in the indoor wet environment has been attached great importance to health.Antibacterial coating is an economical and effective method among many measures.The traditional antibacterial coating has high toxicity and short life cycle.Therefore,the current research hotspot is developing a safe,effective,long-lasting antibacterial and anticorrosion coating.In this paper,the nano-Ag@SiO2 antibacterial agent with core-shell structure was added to the environmentally friendly waterborne acrylic paint,and the antibacterial and anticorrosion coating system was constructed by using epoxy primers with good compatibility.The optimal antibacterial agent concentration was studied in the antibacterial and anticorrosion coating.The antibacterial and anticorrosion properties of the coating system were studied by simulating environmental accelerated test method.The antibacterial mechanism and corrosion mechanism of the functional coating were discussed.The research results were following.The experimental results showed that when the concentration of nano-Ag@SiO2 antibacterial agent in the acrylic topcoat reached 283 ppm,the coating's sterilization rate against E.coli and Staphylococcus aureus reached 100%.The addition of nano-Ag@SiO2 antibacterial agent improves the dispersion of the acrylic coating,which made the surface of the antibacterial and anticorrosion coating more smooth,and improved anticorrosion performance of the coating effectively.For the application in the marine atmospheric environment,antibacterial and anticorrosion coating was subjected to environmental simulation accelerated test by the salt spray test,the damp heat test,and the temperature impact test.It was found that the coating still maintained 100%sterilization rate against E.coli and S.aureus when the antibacterial and anticorrosion coating system was subjected to salt spray acceleration 600h,hot and humid 240h,and temperature shock 10 cycles.It showed the durability of antibacterial performance about antibacterial and anticorrosion coating system under the accelerated test.The study of the electrochemical impedance also showed that the impedance module values of the antibacterial and anticorrosion coating system were reduced,but the corrosion resistance of the coating system was kept well,indicating that the addition of the nano-Ag@SiO2 antibacterial agent enhanced the coating antibacterial properties,and it have no effect on the coating corrosion resistance of the coating.The studies shoued that when antibacterial and anticorrosion coating in the oxygen and oxygen removal water,the concentrations of silver ion gradually increased with the time going by.In comparison,the concentration of silver ions in oxygen-enriched water increased faster and higher than the deoxygenation environment.When the soaking time reached 90 days,the release amount in the oxygenated water was more than three times higher than in the oxygen removal water.This was because the oxygen-containing water enters the inside of the silica core-shell structure through the surface pores of the coating,and the elemental silver undergoes an oxidation reaction and losed electrons to became Ag+.At the same time,oxygen underwent a reduction reaction and combined with water to generate hydroxide.In this case,the concentration of Ag+ in the silica core shell increased and diffused out of the pores.Futhermore,the Fourier infrared test showed that the microscopic mechanism of corrosion in the antibacterial coating was mainly due to the large amount of ester groups in the acrylic coating.Fractures,carboxylates were generated,causing failure of the coating.