| The main material of sea facilities is steel and organic coating is one measure of the effective protection. The demand for long life, environment friendly and high weather resistance coating is more critical and more urgent, but which can't meet with the demand now, especially the weather resistance. Poly (vinyl chloride co-isobutyl vinyl ether) coating will be used extensively for its cleanness and friendliness to environment, but about which has been researched a little. Rutile nano-TiO2 with strong UV shield might improve the weather resistance of coating.To overcome the drawback of traditional coating, in this paper Rutile nano-TiO2 RM301LP was added into the vinyl chloride co-isobutyl vinyl ether to prepare a new kind of coating used in sea air and which was compared to the anatase nano-TiO2 P25 .The exploring study on the application of nano-TiO2 in poly (vinyl chloride co-isobutyl vinyl ether) coating was done. The optimal dispersion conditions was studied through settlement experiment. The study with TEM show that nano-TiO2 was nano-particles in solvent. Weather resistance was studied by the UV accelerated aging experiment. Anti-corrosion ability was studied through electrical impedance spectroscopy impedance experiment. Infra-red spectra(IR) and photoelectron energy spectra(XPS) was used to study the mechanism of the MP25 rensin aging.The stability of nano-TiO2 in organic solvent was studied and found that the nano-TiO2 with different types and surface treatments need obvious different dispersants and different dose. The dose of dispersant for nano-TiO2 is 10~15 times than that for general TiO2.It was found that the weather resistance of the vinyl chloride co-isobutyl vinyl ether was enhanced and the hardness of the coating was enhanced 1-2 grades with addition of rutile paste RM301LP. The anti-seawater and weather resistance of coating increase with the quantity of rutile nano-TiO2 increasing and the two performance was enhanced when the quantity of nano-TiO2 increase. Comparing to the anatase nano-TiO2 P25, rutile paste RM301LP can obviously prevent MP25 resin from aging by ultraviolet ray.The influence of Rutile nano-TiO2 RM301LP on anti-corrosion coating was studied and found that the appropriate quantity of nano-TiO2 could enhance the performance of coating and the quantity is 1.8% of the total mass. At last, the optimal coating formulation was gotten as follows: 0.5-1.0g nano-TiO2 RM301LP, 25.6g MP25 resin, 33.4g xylene, 1.4g chlorinated paraffin, 1.5g 15% slurry of organic bentonite, 0.8g green chrome, 7.7g grey mica ferric oxideand 0.6g non-float aluminum.This formulation may need to be studied further if it will use to produce coating.However the resin aged fast with addition of anatase nano-TiOa P25 for its photoactivate activity. The mechanism of resin under UV radiation as following was put forward: free radicals produced from the surface of nano-TiOj attack the hydrogen of the methylene, then double bond is formed after the dehydrocholrination, and then the chain is broken after the double bond was oxidized by ozone. It was found that chlorine and oxygen were enriched in the surface layer, while titanium in the inner layer. The influence of the effect on the coating need to be further studied.
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