Original scientific paper

https://doi.org/10.5552/drind.2012.1123

Compression Strength of Fir and Beech Wood Modified by Citric Acid

Bogoslav Šefc ; Faculty of Forestry, Zagreb University, Zagreb, Croatia
Jelena Trajković ; Faculty of Forestry, Zagreb University, Zagreb, Croatia
Tomislav Sinković ; Faculty of Forestry, Zagreb University, Zagreb, Croatia
Marin Hasan ; Faculty of Forestry, Zagreb University, Zagreb, Croatia
Iva Ištok ; Faculty of Forestry, Zagreb University, Zagreb, Croatia

Abstract

Previous articles have shown that modification of wood by citric acid (CA) improves dimensional stability and resistance of wood against fungi attack. However, chemical modification of wood also modifies its mechanical properties in some way. The compression strength of wood is one of its representative mechanical properties. Modified wood with lower values of compression strength has limited purpose. The intention of this work is to show the effect of wood modification by citric acid on the compression strength of wood. Fir wood (Abies alba Mill.) and beech wood (Fagus sylvatica L.) were impregnated by citric acid with sodium-dihydrogen-hypophosphite (NaH2PO2) as a catalyst. Part of the impregnated samples together with control samples were cured at the temperature of 140 °C for 10 hours and the remaining samples were cured in microwaves for 35 minutes. The average compression strength parallel to the grain of wood modifi ed by CA, using different regimes of curing, was compared to the strength of unmodifi ed wood. The average compression strength parallel to the grain of wood was retained after modification. In the case of fir wood, the average compression strength was even improved after modification. The results indicate that wood modified by citric acid may be considered for the purposes where compression strength properties are equally important as improved durability and dimensional stability of wood.

Keywords

Fir wood (Abies alba Mill.); beech wood (Fagus sylvatica L.); chemical modification; citric acid (CA); compression strength

Hrčak ID:

78552

URI

https://hrcak.srce.hr/78552

Publication date:

20.3.2012.

Article data in other languages: croatian

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