Zinc tannates with Tara powder as anticorrosive pigments
The aim was to evaluate the anticorrosive properties of alkyd paints and wash primers formulated with zinc tannates containing Tara tannins. Their inhibitory efficiency was compared with paints pigmented with well-known anticorrosive pigments by accelerated corrosion tests (salt spray test, Prohesion test, and sulphur dioxide test), natural exposure tests and some electrochemical techniques (corrosion potential, polarization resistance and impedance measurements). It was demonstrated that the capacity of inhibiting corrosion of zinc tannates is equivalent to that shown by most commercially available conventional pigments, such as zinc phosphate and zinc chromate.
The study is published in: Progress in Organic Coatings Volume 117, April 2018, Pages 35-46.