Investigating the role of surface treated titanium dioxide nanoparticles on self-cleaning behavior of an acrylic facade coating

Abstract

In this study, the addition of silane treated TiO2 nanoparticles on the self-cleaning properties of an acrylic facade coating was evaluated. Tetraethoxyorthosilicate, TEOS, was used for surface treatment of TiO2 nanoparticles. The silica grafting on the TiO2 nanoparticles was characterized via Fourier Transform Infrared spectroscopy, specific surface area measurement, pore size distribution, and real density measurements. The effect of surface treatment and content of nanoparticles on the photocatalytic activity of acrylic coating and self-cleaning properties was studied. For this purpose, the photodegradation of Rhodamine B (Rh.B) dyestuff, as a colorant model, was investigated by colorimetric technique, while the coating samples were exposed to UVA irradiation. Performance of the acrylic coating films was evaluated by gloss change during accelerated weathering conditions. Also, the surface morphology of the coating films was studied using SEM analysis. The results showed that the addition of both treated and untreated TiO2 nanoparticles provides self-cleaning property to the acrylic coatings. However, silica surface treatment of TiO2 nanoparticles reduces the coating degradation caused by TiO2. This is more evident when higher concentrations of the treated TiO2 nanoparticles are used.