The Effect of Nano Silica Type on Some Properties of the Polyurethane Clear Coats

Niknam, M.; Ranjbar, Z.; Baghshahi, S.

The Effect of Nano Silica Type on Some Properties of the Polyurethane Clear Coats

Authors

¹ Materials College, Sciences And Researches Branch, Azad University

² Department of Surface Coatings and Corrosion;Center of Excellence for Color Science and Technology, Institute for Color Science and Technology

³ Department of Technical and Engineering, Imam Khomeini International University

Abstract

The effect of different types of nano silica (nano cristobalite, hydrophilic nano silica and hydrophobic nano silica) on some properties of two component polyurethane clear coat has been studied. Rheometric studies at low shear rates shows a shear thinning behavior in the clear coats containing nano cristobalite and hadrophylic nano silica. The haze value was acceptable for clear coat containing surface treated nano silica (hydrophobic). Nano indentation measurements show the hardness value has increased in presence of nano particles and the scratch depth has decreased.

Keywords