Preserving Anti-Corrosion Properties of Epoxy Based Coatings Simultaneously Exposed to Humidity and UV-Radiation Using Nano Zinc Oxide

Nano zinc oxide-containing epoxy-based coatings were prepared by co-deposition of zinc oxide nano particles and epoxy-based cathodic electrodeposition paint. The films were exposed to UV radiation for different periods and the corrosion resistance properties of the exposed films were evaluated by electrochemical impedance spectroscopy. It was found that the nano zinc oxide stabilized coatings maintain their protective properties even after a prolonged exposure to UV light. The more prolonged retention of protection properties of the coating was assigned to the morphology of the film containing nano ZnO after exposure to UV light. Nano ZnO stabilized coatings show a uniform degradation of the film surface while non-stabilized coating exhibit deep cracks which results in deterioration of the film integrity. UV exposure of non-stabilized films was found to result in formation of deep cracks and non-uniform photodegradation in epoxy coating. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.093203jes] All rights reserved.