NANOPARTICLES-BASED WOOD PRESERVATIVES: THE NEXT GENERATION OF WOOD PROTECTION?

Wood is a natural material that presents a great variation of properties. Many treatments have been developed in order to extend the service life of wood products. Nowadays, products with low toxicity and economic viability are a challenge to researchers. Nanotechnology has been indicated as a solution to this issue, since wood preservatives can be utilized in low concentration, promoting satisfactory results in terms of protection with no color changes. The main goal of this review is to present nanotechnology advances on wood protection. Self-cleaning surfaces, scratch and weathering resistance, and biocides properties have been achieved through nanoparticles (NPs) applications. Studies evaluating the performance of NPs from silver (Ag), boron (B), copper (Cu), zinc (Zn), zinc oxide (ZnO), zinc borate (B2O6Zn3), and titanium dioxide (TiO2) on wood protections have reported promising findings. Tests performed against termites, rot, mold and stain fungi, and UV degradation have demonstrated that some biocides have their properties improved in nanoscale. Controlled release and encapsulation technologies are another important matter once it can increase the effectiveness of wood treatments. NPs risk assessment for human health and the environment are still incipient. Despite of that, some products as nanozinc oxide (nanoZnO) and titanium dioxide (nanoTiO(2)) present encouraging potential. NanoZnO and NanoTiO(2) have been reported as promising antifungals, antibacterials, and antiviral agents; beyond theirs biocides properties, low ecotoxicity impacts to the environment are expected. Based on this review, we consider that wood treatments based on NPs may play an important role in the next generation of wood protection systems.