Characterisation of thermally modified wood: molecular reasons for wood performance improvement

Novel hydrophobization of wood by epoxidized linseed oil. Part 1. Process description and anti-swelling efficiency of the treated wood

“…Regarding W TM , it is well known that, during thermal modification, AA liberated from hemicelluloses catalyses carbohydrate cleavage and leads to a reduction in the degree of polymerization of carbohydrates and formation of new ether linkages between lignin at high temperatures (Tjeerdsma et al 1998;Sivonen et al 2002;Nuopponen et al 2004;Tjeerdsma and Militz 2005;Windeisen et al 2009). Thus, the values of ASE′ for TM samples do not reflect the real reactions occurring in the cell wall during thermal modification.…”

Alteração da cor da madeira de teca por tratamento térmico

“…532 Floresta e Ambiente 2014; 21(4):521-534 Lopes JO, Garcia RA, Latorraca JVF, Nascimento AM (Tjeerdsma et al, 1998;Mitsui et al, 2001;Bekhta & Niemz, 2003 O comportamento diferenciado na alteração da cor da madeira de cerne e alburno de teca, após a aplicação dos tratamentos térmicos, pode ser explicado pelos diferentes teores e/ou natureza química de cada tipo de madeira. Os resultados de variação de cor encontrados para a madeira de cerne de teca podem se assemelhar ao resultado obtido por Gouveia (2008) para a espécie de louro-vermelho, cuja madeira também é escura, sendo classificada no grupo das madeiras marrons, tal como o cerne da teca.…”

Wood production, wood technology, and biotechnological impacts

“…The thermal modification has a high impact on wood chemistry and constructive properties. Thermally modified wood is dominated by aldehydes (hexanal), carboxylic acids and -esters, air dried coniferous wood by terpenes (Tjeerdsma et al 1998).…”

“…Pressing at high forces and temperatures for long periods can create water-resistant bonds (Klauditz & Stegmann 1955, Back 1987, Unbehaun et al 2000. Pyrolytic degradation of hemicellulose sugars and thermal conversion to furan products have been discussed to contribute to the bonding and increase of free reactive sites on the aromatic ring of lignin units and to auto-condensation of lignin (Zavarin 1984, Ellis & Paszner 1994, Tjeerdsma et al 1998, Rowell et al 2002. Boards formed by just pressing fibres have however unfavourable properties: they show high thickness swelling in presence of water and have poor mechanical properties , Unbehaun et al 2000.…”