Gluing properties of wood of three fast-growing plantation species

Glueability of three fast-growing plantation hardwood species viz. Acacia mangium Willd., Gmelina arborea Roxb., and Paraserianthes falcataria Back. were evaluated using phenol-resorcinol formaldehyde (PRF) and urea formaldehyde (UF) resin adhesives formulated to cure at room temperature. PRF and UF glued joints were assesed by block shear test. A total of six combinations were tested ; Three consisted of single-species and the remaining three were mixture of two species laminations. Specimens were tested dry and wet in accordane to America Society for Testing and Materials, ASTM D 905-49(76). Results showed that majority of the species combinations glued with PRF adhesive exceeded the minimum industrial requirements of 5.5 Mega pascal (MPa) and 4.1 MPa for dry and wet conditions, respectively. A. mangium - A. mangium combination exhibited the highest glue joint shear strength of 9.8 MPa and 6.29 MPa for dry and wet, respectively. However, with UF adhesive, none of the species combinations achieved the glue joint strength requirements for dry test. The strongest shear strength was exhibited by P. falcataria - P. falcataria combination at 5.5 MPa. It was also found that the percentage of wood failure did not indicate the respective shear strength of the glue joints. All P. falcataria combinations (dry) with relatively lower shear strength exhibited more than 70% wood failure for both PRF and UF resin adhesives. Physical factors such as species, density, moisture content, shrinkage and swelling properties of wood as well as the inherent characteristics of the adhesive such as viscosity, pH and solid content influence the bonding strength. Plantation species which are generally small in size could be joined with suitable adhesives to form useful dimensions for various end uses.

PDF ID 17831.pdf Restricted to Repository staff only Download (763kB)

Actions (login required)

View Item