Some properties of plywood produced from 10 cultivars of poplar

The aim of this paper is to study the possible influence of poplar cultivar and soil on the mechanical properties of plywood produced from 10 cultivars having grown in different soils. For each cultivar, two trees were harvested per station; crosscut into bolts then peeled 1.4 mm thick for one tree and 3 mm thick for the other one: in total, 80 trees were sampled. The veneers were used to make 160 boards using 2 adhesives: polyvinyl acetate (PVAc) and melamine-urea-formaldehyde (MUF). These boards were then cut into standardized samples for non-destructive and destructive mechanical tests. The properties of plywood were characterized by measuring their density, modulus of elasticity and modulus of rupture. The results showed that poplar plywood properties could be influenced by adhesive and veneer thickness. The cultivar and soil effects were never relevant. A tight correlation was found between destructive and non-destructive modulus of elasticity tests.