Investigation of Nanocopper-Hygrothermally Treated Wood Properties
G Rassam, B Jamnani, A Faraji Heris
Nanometals with high thermal conductivity can be considered as modifiers, especially in thermal modification of wood. This study was aimed to investigate some physical and mechanical properties of nanocopper impregnated Iranian beach (Fagus orientalis Lipsky), which was hygrothermally treated. For this purpose, nanocopper solution (400 ppm) was used for impregnation process. Hygrothermal treatment was carried out at temperatures of 120, 150 and 180ºC for 1, 3 and 5 hours. Volumetric swelling after 24 hours soaking in water (Vol. S24h), moduli of rupture and elasticity (MOR and MOE), compressive strength parallel to the grain (Cs║) and hardness values (H) of specimens were determined. The minimum volumetric swelling of specimens was obtained in nanocopper impregnated specimens at the treatment temperature of 180ºC and duration of 5 hours. MOR, MOE and hardness values were decreased with more increase in temperature. The best values for these properties were obtained in nanocopper impregnated specimens, which were hygrothermally treated at temperature of 120ᵒC for 1 hour. Compressive strength values were decreased by increasing of temperature and duration of hygrothermal treatment and the maximum values of this property were seen in non-impregnated specimens, which were treated at the temperature of 120ᵒC for 1 hour. It was revealed that at temperature of 180ᵒC and duration of 5 hours, there were no significant differences in mechanical properties of nanocopper impregnated and non-impregnated specimens. These results showed that by nanocopper impregnation of wood, hygrothermal treatment could be carried out at higher temperature and longer duration to obtain a wood product with appropriate properties.
Keywords: nanocopper, hygrothermal treatment, beech, modulus of rupture, compressive strength parallel to the grain