Surface coating performance of TiO2 nanoparticle-modified veneered panels and their influence on formaldehyde emission

The physical and mechanical properties of wood and wood-based panels can be effectively improved by modification with nanoparticles. This paper focuses on effects of modifying veneer with titanium dioxide (TiO 2 ) nanoparticles on the performance of a waterborne coating and formaldehyde emission. Commercial waterborne varnish was used to apply a surface finish on the modified veneered panels. Changes caused by TiO 2 nanoparticle treatment that could affect the finishing performance were measured. The results showed slight increases in the weight and contact angle of the veneers treated with TiO 2 nanoparticles, whereas the modified veneered panels after surface finishing presented improved hardness at high nanoparticle loadings. Modification of the veneers by nanoparticles had a minor negative influence on the coating glossiness and adhesion due to a blocking effect between the coating film and the modified veneers. Formaldehyde emissions were considerably reduced due to degradation by the TiO 2 particles under UV-light irritation.