Improving Anti-Aging Coatings by Coupling of Organic and Inorganic Ultraviolet Absorbers

Abstract

The individual organic or inorganic ultraviolet absorbers contain absorption bands in different wavelength regions below 400nm, and the coupling of the two types of absorbers can improve anti-aging properties of coatings to prolong the service lifetime. Nanosized rutile and two typical commercial organic ultraviolet absorbers 2 - hydroxyl - 4 - n - octyloxybenzophenone (UV-531) and 2 - (3 - tert - butyl - 2 - hydroxyl - 5 - methylphenyl) - 5 - chloro - 2H - benzotriazole (UV-326) were coupled. Optical property of the hybrid ultraviolet (UV) absorbers was measured by UV-vis. The anti-aging property of polyacrylate coatings added with UV absorbers was carried out in a weatherometer and investigated by chalking and FTIR. The results show that hybrid UV absorbers have better performances of UV absorption with synergistic effects than both organic and inorganic components. In addition to improving the protection against UV, the coatings properties of adhesive, pencil hardness and stain resistance were increased by adding hybrid UV absorbers. The anti-aging mechanism of UV absorbers was analyzed.