Durability and mechanical performance of a photo-catalytic water-based nanocomposite coating

Abstract

Abstract In this study, different combinations of nanoparticles including; TiO 2 , SiO 2 , silica grafted TiO 2 , titania grafted SiO 2 , physical blends of TiO 2 /SiO 2 nanoparticles and nanocomposite particles made of titanium tetra-isopropoxide/tetraethylorthosilicate (TTIP/TEOS) precursors, were loaded into an acrylic emulsion coating. Photo-activity of the coatings was evaluated through the photo-degradation of Rhodamine B dyestuff, as a pollutant model, on the surface of the coatings under UVA irradiation. The coating films were exposed to accelerated weathering conditions for different time intervals. As the criteria for durability of the coatings, morphology and topology of coatings surface were studied using scanning electron microscopy (SEM) and atomic force microscopic (AFM) techniques, respectively. Mechanical properties of the coatings were assessed before and after exposure to accelerated weathering conditions. The results exhibited a favorable balance of photocatalytic activity and mechanical properties in the coatings containing TTIP/TEOS nano-composite particles even after exposing to the accelerated weathering conditions.