Effects of photocatalytic activity of nano TiO2 and PAni/TiO2 nanocomposite on the physical/mechanical performances of acrylic pseudo paints

Abstract

Abstract Today, photo-catalysts are considered for purification of air and wastewater from organic pollutants. The method is based on photo oxidation of pollutants and their decomposition to CO2 and mineral products. The aim of this research is the investigation of changes in the mechanical properties of acrylic pseudo-paints contained nano TiO2 and PAni/TiO2 nanocomposite after photocatalytic degradation of Benzene under UV irradiation. For this purpose, different contents of nano-catalysts (i.e. 1, 2, and 5\u202fwt.%) were applied to acrylic latex. In some samples 10\u202fwt.% of TiO2 pigment and 5\u202fwt.% of CaCO3 were also used to produce pseudo paint samples. The photocatalytic oxidation (PCO) activity of the samples was measured using gas chromatography (GC) analysis. The tensile properties (i.e. tensile strength, modulus, toughness, and elongation at break) of the samples were evaluated before and after PCO activity. The morphology of the samples was characterized using scanning electron microscopy (SEM). The overall color changes in the pseudo paints as a criteria for determining the photo degradation of the samples due to PCO activity were measured. A good correlation between GC results and the mechanical properties was found. Results showed that at 2\u202fwt.% of nano TiO2 maximum amounts of the mechanical and photocatalytic properties were achieved. It was also found that by introducing PAni/TiO2 to the acrylic films, the mechanical properties were decreased considerably compared to the nano TiO2 containing samples. It was attributed to the crystalline nature of PAni or immiscibility of PAni and acrylic matrix which was confirmed by DMTA results.