Waterborne anticorrosive systems for steel protection -: Part 1:: Formulation and testing

The development of water-based anticorrosive systems as well as the assessment of its anticorrosive properties through different conventional tests are discussed in this work. Steel panels coated with different painting systems were subjected to standardized (salt spray, humidity chamber adhesion, and flexibility) tests. The binder used in this research was prepared in the laboratory by emulsion polymerization of styrene and acrylic monomers. Three ecological pigments were used: two phosphate-based and one prepared in the laboratory using a tannin-based recipe. Two levels of pigment charge were tested. The commonly used zinc tetraoxychromate pigment in solvent-borne coatings was included as reference. It was found that the ecologically friendly formulations tested in this work protect steel against corrosion effectively. The zinc tetraoxychromate pigment was not suitable for the binder used in this work as judged by the inferior corrosion protection of formulations containing it. Possible reasons based on binder-pigment interactions are discussed.