Some physical properties of plywood produced from beech, poplar and eucalyptus veneers

Abstract

In this study, in three different combinations and five ply plywood boards were produced from beech (Fagus orientalis L.), eucalyptus (Eucalyptus grandis W. Hill ex Maiden) and hybrid poplar (Populus x euramericana I-214 clone) rotary cut veneers using urea-formaldehyde (UF), melamine-urea formaldehyde (MUF) and phenol-formaldehyde (PF) adhesives. Physical properties e.g. air-dry density, thickness swelling and water absorption of produced plywood boards were determined. The measurements of thickness swelling and water absorption were made at the end of 2, 24, 168 and 336 h times. The effects of factors of adhesive type, combination type and time on the thickness swelling and water absorption were investigated. As a result of ANOVA test, it was determined that the effects of all three factors on the thickness swelling and water absorption were significant, statistically. According to adhesive type, the lowest thickness swelling and water absorption were determined on the plywood bonded with MUF, the highest were determined on the plywood bonded with PF. According to combination type, the lowest thickness swelling was determined on the plywood produced with eucalyptus and poplar combination. The lowest water absorption was determined on the plywood produced with beech and eucalyptus combination. Keywords: Plywood, Thickness swelling, Water absorption, Eucalyptus, Poplar, Beech