Efeito de nanopartículas de ZnO na resistência da madeira de pinus tratada termicamente à radiação UV

Abstract

The objective of this study was to evaluate the effect of zinc oxide (ZnO) nanoparticles on the color stability of heat-treated pine wood after exposure to ultraviolet (UV) radiation. Wood samples were heat-treated at 180, 200 and 220°C for 2 h and impregnated with a solution of 1.5% ZnO nanoparticles under pressure and vacuum. The material was exposed to UV radiation during 168 h and color measurements were taken every 42 hours. Color measurements were realized on the CIE 1976 L∗a∗b∗ space. UV radiation changed wood color. ZnO nanoparticles were ineffective to protect the untreated wood. However, nanoparticles associated to heat treatment at 220°C improved the resistance of wood to UV radiation.