Effect of metal nanoparticles on hardness in particleboard

Effects were studied of 200 ppm silver and copper nano-suspensions, with size range from 20 to 80 nm, on the hardness of particleboards produced at an industrial scale at the Iran-Choob Factory, Iran. Metal nano-suspensions were added to the mat at two levels of 100 and 150 milli-liters/kg dry weight wood particles, and the results were compared with those of the control panels. Results showed that the high thermal conductivity coefficient of silver nanoparticles broke down part of the resin bonds; it also heat-treated the surface wood particles, resulting in significant decrease in the hardness of treatment with 150 mL/kg. However, in the nanocopper-treated panels, no significant change was observed due to the lower thermal conductivity coefficient of copper; furthermore, as to the formation of higher hydroxyl bonds, it even slightly increased. High significant correlations were determined between most of the physical and mechanical properties of the panels.