This study aimed at determining the equilibrium moisture content of wood panels in a climatization chamber and comparing the values of equilibrium moisture content found with those given by Nelson's equation. The research was developed at the Experimental Unit of Wood Panel Production of the Universidade Federal de Lavras. Samples of particleboard, plywood, hardboard, OSB (Oriented Strand Board), MDF (Medium Density Fiberboard), HDF (High Density Fiberboard), cement wood and plastic wood were taken both from commercial wood and from experiments and trials. The specimen dimensions were 2.60 cm width by 2.60 cm length, and thickness commercially used of each product. Five repetitions were carried out for each panel. The specimens were weighted and then taken to the climatization chamber under different conditions of relative humidity (90, 80, 70, 60, 50 and 40%) at 30ºC. The hysteresis and equilibrium moisture content ranged from 40 to 90%. The results indicate that Nelson's equation is efficient for estimating the equilibrium moisture content and that there is no hysteresis difference in the studied products. All of them presented the same dimensional stability. It was also observed that panel coating did not affect the equilibrium moisture content.
Equilibrium moisture content; isotherms; sorption Nelson's equation; wood panels
