Enhancing the performance of exterior waterborne coatings for wood by inorganic nanosized UV absorbers

Enhancing the durability of the architectural wood coatings is essential for a successful commercialization of the forest products. Therefore, this paper is focused on UV resistant waterborne nanocomposites coatings for exterior uses of wood, which were improved with inorganic UV absorbers such as zinc oxide and titanium dioxide nanoparticles. The performance of such nanocomposites coatings applied on black spruce boards was demonstrated trough accelerated weathering. Artificial aging behavior of the coatings was followed by color, gloss and thickness changes. Scanning electron microscopy and transmission electron microscopy was used to investigate nanoparticles dispersion in nanocomposite dry films. Fourier Transform Infrared Spectroscopy was used to characterize the chemical modification of the weathered coatings surface. The results have shown significant improvement in UV-shielding of the nanocomposites coatings. Depending of aging criteria, a selection of the best nanocomposite coatings formulations for exterior wood could be done.