Response of hygroscopicity to heat treatment and its relation to durability of thermally modified wood

• Published in: Construction & building materials 2017-07, Vol.144, p.671-676
• Main Authors: Li, Tao, Cheng, Da-li, Avramidis, Stavros, Wålinder, Magnus E.P., Zhou, Ding-guo
• Format: Article
• Language: English
• Subjects: Durability; Hailwood-Horrobin model; Heat treatment process; Hygroscopicity; Poplar wood
• ISSN: 0950-0618; 1879-0526; 1879-0526
• DOI: 10.1016/j.conbuildmat.2017.03.218

•Hailwood-Horrobin model calculates moisture adsorption of thermally modified wood.•The m0 is a critical property of moisture adsorption for thermally modified wood.•A correlation between m0 and durability of thermally modified wood was found.•An m0-based method is proposed to evaluate durability of thermally modified wood. In an attempt to study the effect of heat treatment on hygroscopicity and durability of wood, Poplar (Populus spp.) wood was thermally modified using five different temperatures between 170°C and 210°C, for a fixed duration of 3h. Moisture adsorption behavior and the resistance to soft rot fungi were investigated thereafter. Based on the Hailwood-Horrobin sorption model, the amount of available sorption sites within specimens for the different groups of Poplar wood were calculated from the model’s m0 parameter. Chemical analysis of the changes in wood components induced by heat treatment allows for a comparison between the easily obtained m0 and the results of time-consuming wood decay tests. The proposed m0-based method for highly efficient evaluation and prediction of durability of thermally modified wood could optimize future research on the mechanisms of heat treatment processes.