Chemical modification of wood with thermosetting resin: effect on dimensional stability and strength property

Abstract

The effects on dimensional stability and strength property of a soft-wood ( Anthocephalus cadamba Miq.) treated with thermosetting resins; phenol formaldehyde (PF), melamine formaldehyde (MF) and urea formaldehyde (UF), were studied. Dimensional stability efficiencies of 70.59%, 68.23% and 48.5% were obtained at about 33–35 levels of weight percent gain (WPG) for PF, MF and UF resins, respectively, when wood samples were treated with 30% resin concentration at 90–100°C and 75 psi air pressure. These levels of WPG of polymers caused 9–15% bulking coefficient (BC) and 31–47% moisture excluding efficiency (MEE) of treated wood. Repeated wetting and drying did not change the value of BC and anti-shrink efficiency (ASE) of treated samples. The treatment also increased the modulus of rupture (MOR) and modulus of elasticity (MOE) by 12–20% and 5–12%, respectively, at 33–35 WPG. Furthermore, the treated wood samples showed resistance to termite ( Odontotermis spp .) attack.