The Waterborne Symposium

Abstract
UV-VIS Resistant Acrylic Latexes For Wood Coating Applications by Encapsilation of Inorganic NPS Using Miniemulsion Polymerization
Co-authors: Anna M. Ritcey, and Véronic Landry

Translucent coatings containing UV absorbers, hindered amine light stabilizers (HALS) and biocides can substantially slow down the weathering process of wood and maintain its natural colour for a period of time.  However, there are few commercially available coatings that can push refinishing intervals past two or three years, which is partly explained by the premature photodegradation and the leaching of additives in coatings.  In our previous work, it was shown that nanoparticles could efficiently be encapsulated in the polymer matrix to develop a coating resistant to black-stain fungi.  Based on these results, inorganic (zinc oxide and silver) nanoparticles with various sizes were functionalized and incorporated in acrylic polymer particles via miniemulsion polymerization.  The formulations were applied on white spruce (Picea glauca) and exposed to 2,000 hours of accelerated UV radiation, and evaluated against a control formulation containing a commercial UV absorber.  The comparison between the various systems was based on color and gloss retention, FTIR spectroscopy, and variation in the glass transition temperature.  After 1,000 hours of accelerated UV exposure, results suggest that zinc oxide and silver nanoparticles could be used in the development of UV-Vis resistant clear coatings for wood.