Nano-cerium dioxide synergistic potential on abrasion resistance and surface properties of polyurethane-nanocomposite coatings for esthetic and decorative applications on wood

Abstract

Development of an antiabrasion and optical shield clearcoat for wooden art and decorative works improves its esthetic durability and lifetime. In this study, the synergistic potentials of cerium dioxide nanoparticles (NPs) were exploited to improve the abrasive, structural, and surface properties of polyurethane (PU)/silica nanocomposite coatings applied on the thermally modified spruce wood. Microhardness, adhesion strength, contact angle, and UV–Vis spectroscopy were used to evaluate the nanocomposite coatings’ surface properties. FE-SEM and EDS techniques were also employed to scrutinize distribution of NPs in the structure of nanocomposite coatings. The results showed that the abrasion resistance significantly improves by increasing the content of silica NPs. However, microhardness and performance of nanocomposite coatings containing a high percentage of silica diminished due to the aggregation of NPs and poor crosslinking of the polymer matrix. The presence of cerium dioxide NPs as a synergistic function in the PU coatings containing nano-silica enhanced the abrasion resistance as well as the glass transition temperature and caused enhanced hardness. Incorporation of cerium dioxide NPs exhibited an incremental effect on the adhesion strength of nanocomposite coatings. However, its presence in high concentration caused an adverse impact on the transparency of the nanocomposite films. In addition, wettability of PU/silica composites remained constant after incorporating high levels of cerium oxide NPs. These findings suggest that use of Ce–Si NPs hybrid/blend in the structure of PU coatings can assure the durability of wood coatings for esthetic applications and interior decoration by strengthening the surface, mechanical, and optical properties.