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The toughness of hygrothermally modified wood

COST Action FP0904 2010-2014: Thermo-hydro-mechanical wood behavior and processing

Mark Hughes, Callum Hill and Alexander Pfriem
From the journal Holzforschung


The mechanical properties of thermally modified wood are discussed with regard to toughness. The molecular origins of the mechanical properties and, in particular, the role of the hemicelluloses are considered. The important role of water and its interaction with the cell wall components is also examined. The properties are discussed from the point of view of composite theory, with the three main macromolecular components acting as reinforcement, matrix and interfacial coupling agent. The important role that hemicelluloses play as a coupling agent between the cellulosic microfibril reinforcement and the lignin-rich matrix is highlighted. Destruction of the hemicelluloses during the thermal modification process has a profound effect upon the mechanical behaviour.

Corresponding author: Mark Hughes, Department of Forest Products Technology, Aalto University, Espoo, Finland, Phone: +358-50-512-2615, e-mail:


This paper reviews the results of COST Action FP0904 Thermo-Hydro-Mechanical Wood Behaviour and Processing. The support given by COST (European Cooperation for Science and Technology) is gratefully acknowledged.


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Received: 2014-6-26
Accepted: 2015-3-27
Published Online: 2015-4-29
Published in Print: 2015-9-1

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