Application of Nelson's Sorption Isotherm to Wood Composites and Overlays


  • Qinglin Wu


Adsorption, desorption, model, moisture, panel products


Equilibrium moisture content (EMC) as a function of relative humidity (RH) was measured in oriented strandboard, particleboard, medium-density fiberboard, hardboard, high pressure laminates, and solid wood. The measurements were made in both adsorption and desorption at 25°C. The EMCRH data were fit to Nelson's sorption isotherm. It was found that Nelson's model can be used to describe the experimental data from different composite materials. The parameters that define the sorption isotherm varied with material type and sorption mode. Determination of the model parameters for various products allows the use of the model as a tool for predicting moisture change in wood-based products under varying environmental conditions.


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