Acrylic Resin Derivatives as Modifier for Potassium Silicate Binder in Zinc-Rich Coatings: Electrochemical Studies

Water based inorganic alkali silicate binder of zinc rich primer was modified by adding acrylic resin derivatives. Several series of primer coatings were formulated by adding 5, 10 and 15 wt% of acrylic and acrylic/styrene copolymer to potassium silicate binder and used as binder in zinc rich coatings. The formulated primers were applied on low carbon steel plates and the corrosion protection properties of these primers were evaluated by electrochemical impedance spectroscopy (EIS), corrosion potential measurements, salt fog test and scanning electron microscope (SEM). The results indicated that the addition of 5% acrylic/styrene copolymer and/or 10% acrylic resin into the inorganic silicate binder led to improvement of corrosion protection performance of formulated primers