Effect Of Zinc Powder Morphology And Graphene Content On Anticorrosion Performance Of Epoxy Zinc Containing Coatings

Epoxy zinc-rich coating is based on the cathodic protection of zinc powder on the surface of steel.At the same time,it uses the excellent corrosion and adhesion properties of epoxy resin.It is widely used in the anticorrosion industry at home and abroad.High zinc content coatings inevitably produce zinc oxide dust during thermal processing such as welding and cutting,which pollutes the environment and endangers the health of construction workers.In this paper,flaky zinc powder was used in place of spherical zinc powder to prepare a low-zinc epoxy zinc-containing coating.The effect of different zinc contents on the anticorrosive performance of flaky epoxy zinc-containing coating(FZP)was studied.Methylpyrrolidone was used to ultrasonically disperse graphene to prepare epoxy zinc-containing coatings with different amounts of graphene.The anticorrosive mechanism of graphene epoxy zinc-containing coatings was studied.(1)FZP coatings were prepared using planetary ball mill dispersion and vertical sand mill dispersion methods.The anti-corrosion performance.of FZP coatings after vertical sand mill dispersion are superior to planetary ball mill dispersion coatings because of their uniform zinc powder distribution..(2)FZP coatings with different flaky zinc powder additions(20,30,35,40 wt.%)and 60% spherical zinc powder epoxy coating(SZP)were prepared,It can be found that both 35% FZP and 60% SZP coatings can maintain a cathodic protection time of about 800 hours,so 35% flaky zinc powder can replace 60% spherical zinc powder to achieve the same anticorrosive effect.(3)FZP coatings with different graphene additions(0.2,0.5,1,2 wt.%)were prepared.The cathodic protection time of the 0.2 wt.% Graphene content coating was similar to that of 35% FZP coating.The cathodic protection time of the 0.2wt.% Graphene content coating is similar to that of 35% FZP coating.The addition of graphene enhances the shielding performance of the coating.Coating defects caused by poor dispersion of pigments and fillers in high content graphene coatings Influence,the duration of cathodic protection is reduced and the corrosion resistance is reduced.(4)A 0.2wt.% Graphene content 60% SZP coating is prepared.The addition of graphene increases the zinc powder corrosion reaction resistance in the early stage and reduces the zinc powder corrosion reaction resistance in the later stage,which enables the zinc powder to be uniformly activated,prolongs the cathodic protection time,and improves Anti-corrosive performance.