The performance of zinc molybdenum phosphate in anticorrosive paints by accelerated and electrochemical tests
Red lead and zinc chromates are doubtless efficient pigments to protect metáis against corrosión. Their use in paints formulation is being restricted due to their deleterious action. Zinc phosphate wasfirstly suggested to replace toxic chromates. However, data on their anticorrosive properties are not conclusive; so, a second generation of phosphate pigments, including zinc molybdenum phosphate, was developed In this paper, the anticorrosive behavior of micronized zinc molybdenum phosphate in paints with 30% of the pigment by volume and a PVC/CPVC ratio 0.8, formulated with different binders (alkyd, vinyl, chlorinated rubber and epoxy resins), was assessed by accelerated (salt spray cábinet and accelerated weathering) and electrochemical tests. Epoxy and chlorinated rubber paints showed the best anticorrosive performance. The inhibitive action of zinc molybdenum phosphate was confirmed Good correlation has been obtained between salt spray and electrochemical tests.