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Graphite/TiO2 nanocomposite additive was used to make a photocatalytic, hydrophilic, and antibacterial polyacrylic based coating. Various amounts of nanocomposite additive with different weight ratios of graphite to TiO2 were used in a commercial grade polyacrylic matrix and the properties of the related coating were investigated and compared with the polyacrylic coating not containing a nanocomposite additive. FTIR, XRD, FESEM, and UV-Vis spectroscopy were applied to characterize the nanocomposite additive and coating. The water contact angle of additive contained polyacrylic coating reached less than 10° after 24 h illumination of LED lamp light. Photodecolorization efficiency of methylene blue dye aqueous solution in the presence of modified coatings reached 47% during 5 h LED lamp irradiation. The nanocomposite additive formulated coatings exhibited good stability in water environment and antibacterial property against Bacillus anthracis and Staphylococcus aureus Gram positive species. Surfactant presence in the coating formulation and electron-hole pairs produced in graphite/TiO2 nanocomposite additive under LED lamp light prevented the growth of bacterial species. Graphite also adsorbed the bacteria species and kept them in vicinity of antibacterial agents. According to the results, polyacrylic coating containing 3% of graphite/TiO2 nanocomposite additive with graphite to TiO2 weight ratio of 20:100 is proposed as the best coating formulation with the considerable properties between the all of formulations examined in this paper. [ABSTRACT FROM AUTHOR]

In order to reach an antibacterial, photocatalytic, and hydrophilic coating, commercial grade polyurethane (CPU) resin was modified with silver ion exchanged montmorillonite/TiO2 nanocomposite in various montmorillonite to TiO2 nanoparticle ratios. To characterize the prepared nanocomposites and coatings, X-ray diffraction patterns, FTIR and UV–Vis spectroscopy and SEM images were used. The modified commercial grade polyurethane coatings containing nanocomposites show better properties, including hydrophilicity, degradation of organic pollutants, antibacterial activity and water resistivity, compared to unmodified commercial grade polyurethane coatings. The water droplet contact angle of unmodified CPU coating was 70°, however it decreased to lower than 10° in modified CPU coatings after 24 h LED lamp irradiation. Decolorization efficiency of malachite green dye solution by the use of modified CPU coatings achieved up to 70% after 5 h LED lamp illumination, compared to less than 5% for unmodified CPU coatings. Modified CPU coatings also showed significant water resistivity and antibacterial properties. [ABSTRACT FROM AUTHOR]