Water vapour sorption behaviour of thermally modified wood

Abstract

The work presented in this paper reports on the water sorption properties of thermally modified wood, densified wood and wood modified using a combination of the two methods. The paper presents new findings concerning the sorption isotherms and sorption kinetics behaviour. The sorption kinetics is analysed in terms of the parallel exponential kinetics (PEK) model which has recently been introduced to the wood science community as a better alternative to the often used Fickian models, at least where cell wall sorption behaviour is considered. The PEK model comprises two exponential sorption kinetic terms which are termed fast and slow sorption processes. The PEK model is then interpreted by using a relaxation-limited kinetics model consisting of two series-coupled Kelvin–Voigt elements.

Keywords:

• Thermal modification
• Water vapour sorption
• Kinetics
• Rheology

Callum Hill acknowledges the support of the Scottish Funding Council for the Joint Research Institute in Civil and Environmental Engineering, which is part of the Edinburgh Research Partnership in Engineering and Mathematics.

Notes

This paper is part of a special issue on the Sixth European Conference on Wood Modification