s Ghaffari - Dept of Engineering, Islamic Azad University, Tehran South Branch, 11365/4435, Tehran, Iran
a Salimi - Dept of Color, Resin & Surface coatings, Iran Polymer & Petrochemical Institute (IPPI), 14965/115, Tehran, Iran
m Khorasani - Dept of Polymer Engineering and Color Technology, Amirkabir University of Technology, 15875-4413, Tehran, Iran

Due to their outstanding properties such as chemical and weathering resistance and good mechanical properties, nano additives were employed into organic binder clear coats. Theproper dispersion of nano silica into organic binder is challenging task in obtaining good physical and mechanical properties of urethane-acrylic clear coats [1-3].