Effect of pressure duration on physical, mechanical, and combustibility characteristics of laminated veneer lumber (LVL) made with hybrid poplar clones

Abstract

Experimental eight-ply laminated veneer lumbers (LVLs) from rotary peeled I-214 (Populus x Euramericana) and I-77/51 (Populus deltoides)fast growing hybrid poplar clones were successfully manufactured using three different press durations (18, 24, and 30 min) with a melamine urea formaldehyde (MUF) adhesive. The effect of press durations on LVLs’ selected physical, mechanical, and combustibility characteristics were determined. The results showed that press duration affected dimensional stability (thickness swelling and water absorption), modulus of rupture, and/or compression strength parallel to grain, depending on the clone types. Improvement in dimensional stability and some mechanical properties of LVLs can be achieved by proper curing of the MUF adhesive. On the other hand, the press durations did not affect oven-dry densities, modulus of elasticity, and the combustibility (weight loss after completion of the test). For improved physical and mechanical properties, up to a 30 min press duration can be recommended. This is necessary for LVLs when they are to be used under conditions where water and/or high humidity is present.

Physical and mechanical properties of laminated wood made from heat-treated Scotch pine reinforced with carbon fiber

“…The temperature applied during the production of the test specimens with PF may have caused to thermo-mechanical densification and consequently this situation may have been caused an increase in MOR and MOE. In previous studies, it was reported that the mechanical properties of bonded wood materials produced using different adhesives change depended on the type of adhesive, press pressure, press temperature, and press time (Uysal et al 2010;Altinok et al 2011;Kurt et al 2011;Onat and Özdemir 2020).…”

Physical and Mechanical Properties of Light Red Meranti Treated with Boron Preservatives

“…The problem with boron compounds is their inherent low solubility into wood as highlighted by (Nunes et al, 2023). Factors such as the wood type, sample size, preservative concentration, and preservative treatment type often vary from studies as they contribute significantly to the efficacy of the treatment such as in Colakoglu et al (2003), Kurt (2008), Yusof et al (2023).…”

Effects of press pressure on glue line thickness and properties of laminated veneer lumber glued with melamine urea formaldehyde adhesive

“…Gluing, pressing, and curing are key steps in LVLs manufacturing that determine strength and durability (Kurt et al 2011). The quality and success of the pressing operation depends on suitable heat, press duration, and press pressure.…”