Preparation And Properties Of Anti-flash Rust Waterborne Acrylic Anticorrosive Coatings And Compound Flash Rust Inhibitor

Waterborne coatings are sprayed on the metal substrates,where the flash rust will appear easily.Therefore,it is necessary to add flash rust inhibitor into the waterborne coatings.For the substrates with serious flash rust,waterborne coatings need more flash rust inhibitor.However,most of the commercially available flash rust inhibitor contains nitrite compounds,which may cause certain damage to the anti-corrosion performance of paint film owing to good watersolubility.And they are also a kind of toxic indirect carcinogen.Consequently,in this paper,the anti-flash rust waterborne acrylic anticorrosive coatings with excellent comprehensive properties were prepared by rationally optimizing the formulation design.On the other hand,the method of compounding different corrosion inhibitor was taken to prepare a low toxic and environment-friendly flash rust inhibitor for the nitrite compounds-free coatings.The research contents are divided into two parts:1.In the first part,the influences of the film-forming resin,the type and proportion of pigments and fillers,the volume concentration of pigments and fillers(PVC),and the additive on the properties of the coatings were discussed.The experimental results showed that: When acrylic emulsion H414 was used as film-forming resin in the formulation system,precipitated barium sulfate and wollastonite powder with the mass ratio 7:3 as body fillers,and zinc phosphate with the mass ratio 1:1 compared to body filler as anti-rust pigment,25% PVC,the paint film had the best comprehensive performance;When the amount of the dispersant DP1060 H and silane coupling agent KH790 was 7% and 0.6% respectively,the paint film had the best anti-corrosion performance and storage stability;With the N,N-dimethyl ethanol amine(DMEA)addition amount of 1.2%,there was not flash rust on the cast iron.The main properties of the prepared anti-flash rust waterborne acrylic anticorrosive coating were as follows: 0 grade adhesion,1mm flexibility,360 h water resistance and 200 h neutral salt spray resistance,which met the primer standard of JG/T 224-2007 and HG/T 5176-2017.2.In the second part,the influences of single corrosion inhibitor,compound corrosion inhibitor,organic alcohol amine type and ratio on the paint films were investigated.A low toxic and environment-friendly compound flash rust inhibitor was prepared,and its inhibition effect on different substrates was tested.The experimental results showed that when the ratio of ammonium molybdate,ammonium benzoate and benzotriazole(BTA)was determined to be1:3:1,the overall properties of the compound corrosion inhibitor were the best for the coatings.When 2-(methylamino)ethanol was used as organic alcohol amine with the mass ratio 1:0.75 compared to compound inhibitor,the compound flash rust inhibitor had the best effect of inhibiting flash rust,which could effectively solve the flash rust problem of different substrates.In comparison with the commercially available nitrite compounds,the compound flash rust inhibitor was somewhat insufficient to inhibit flash rust,but it had a significant improvement on the anti-corrosion property of the coatings.