Thermogravimetric analysis of fungus-degraded lime wood

Lime wood samples decayed under the attack of the soft rot fungus Chaetomium globosum, for different durations, have been obtained. The degree of decay was determined by mass loss, which was of 50.4% after 133 days. The samples were analyzed by thermogravimetry. The degradative modification of the wood due to presence of the fungus was evidenced by structural changes, also affecting thermal properties both with respect to wood hydrophilicity (evidenced mainly in the desorption process) and decomposition behavior. The increased characteristic temperatures for water desorption and decreased temperatures for decomposition processes. as well as the lower thermal stability, could be explained by the formation of reactive species due to oxidation reactions induced by enzymes and the demethoxylation of lignin structure. (C) 2009 Elsevier Ltd. All rights reserved.