Application of the Guggenheim, Anderson, de Boer equation to study the impact of sealing treatments on pine wood sorption characteristics

Surface treatments can modify the materials behavior toward water sorption phenomena. The Guggenheim–Andersen–de Boer sorption equation, already used in the past to study various wood species, is here proposed to investigate the sorption behavior of pine wood samples treated with different sealing material. Particularly, the paper aims to explore the modification of the k parameter with the applied coating. Measurements of sorption–desorption branches permitted to clearly distinguish the behavior of treated samples, the relative humidity (RH) conditions over which they are more dimensionally stable, as well as their tendency to swell and shrink. The proposed study permitted to evaluate the usefulness of the k parameter as an indicator of the presence of chemical treatments on wood at high RH values. Particularly, the k value has been found to change as a function of chemicals surface treatments limiting in different ways the access and expulsion of water moisture.

Highlights

• Surface sealed pine wood samples were analyzed by vacuum microbalance.
• The Guggenheim–Andersen–de Boer equation has been applied to water sorption–desorption data.
• The equilibrium moisture content and its first derivative explained samples swelling/shrinking tendency.
• Assessment of the usefulness of k as indicator of the wood treatment at high relative humidity values.
• Assessment of k modifications in relation to the type of sealing treatment.