Abstracts
This study aimed to evaluate the effect of thermal treatment on the physical properties of juvenile and mature woods of Eucalyptus grandis. Boards were taken from 30-year-old E. grandis trees. The boards were thermally modified at 180 °C in the Laboratory of Wood Drying and Preservation at UNESP, Botucatu, Sao Paulo state, Brazil. The results showed that thermal modification caused: (1) decrease of 6.8% in the density at 0% equilibrium moisture content of mature wood; (2) significant decreases of 14.7% and 35.6% in the maximum volumetric swellings of juvenile and mature woods, respectively; (3) significant decreases of 13.7% and 21.3% in the equilibrium moisture content of juvenile and mature woods, respectively. The influence of thermal modification in juvenile wood was lower than in mature wood and caused greater uniformity in the physical variations between these types of wood in E. grandis.
thermally-modified wood; eucalyptus; maximum swellings; wood density
Este estudo teve como objetivo avaliar o efeito do tratamento de modificação térmica nas propriedades físicas dos lenhos juvenil e adulto da madeira de Eucalyptus grandis. Para tanto, tábuas centrais foram obtidas de árvores de E. grandis com 30 anos de idade. Esse material foi modificado termicamente a 180 °C no Laboratório de Secagem e Preservação de Madeiras da UNESP, Botucatu-SP, Brasil. Os resultados mostraram que o tratamento de modificação térmica ocasionou: (1) decréscimo de 6,8% na densidade a 0% de umidade no lenho adulto; (2) redução significativa de 14,7% e 35,6% nos inchamentos volumétricos máximos dos lenhos juvenil e adulto, respectivamente; (3) diminuição significativa de 13,7% e 21,3% no teor de umidade de equilíbrio dos lenhos juvenil e adulto, respectivamente. A influência da modificação térmica no lenho juvenil foi menor do que no lenho adulto e ocasionou uma maior uniformização nas propriedades físicas entre esses dois tipos de lenho da madeira de E. grandis.
madeira modificada termicamente; eucalipto; inchamentos máximos; densidade da madeira
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Publication Dates
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Publication in this collection
11 Feb 2014 -
Date of issue
Mar 2014
History
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Accepted
12 Mar 2013 -
Received
20 June 2013