Static Bending Strength of Heat-Treated and Chromated Copper Arsenate-Treated Plywood

Abstract

aPlywood can be used in the furniture industry and in civil construction due to its structural strength. However, for long useful life in construction, especially in tropical countries, it needs to undergo treatments against xylophagous organisms. The most common preservative treatment is the chemical chromated copper arsenate (CCA); there are alternatives, such as heat treatment, that do not use chemicals. The objective of this work was to evaluate the mechanical resistance of CCA and heat-treated plywood prepared at three different temperatures (160 °C, 180 °C, and 200 °C). Pinus taeda plywood with seven veneers and phenol-formaldehyde adhesive was produced and subjected to the preservative treatments. The results showed that the CCA treatment reduced the mechanical strength of the panels, while the heat treatment did not. Heat treatment also decreased panel hygroscopicity, indicating a better dimensional stability.

Influence of CCA-A preservative on physical-mechanical properties of Brazilian tropical woods

“…Other researchers have been analyzing the behavior of other wood species after the chemical treatment, as Faria et al (2015), who analyzed the influence of CCA preservation on the physical-mechanical properties of Eucalyptus camaldulensis wood, and concluded that the treated wood presented improvements in the values of the properties analyzed. Ferreira et al (2017) analyzed the influence of the chemical treatment with CCA on the conventional strength in the static bending test in wood panels of Pinus taeda and concluded that the treatment increased the moisture content of the panel and decreased its mechanical strength. Segundinho et al (2017) studied the efficiency of the bonding of treated wood of Eucalyptus cloeziana for the production of glued laminated wood and concluded that CCA interfered negatively in the properties of basic density and shear strength parallel to the fibers.…”

Effect of Alkyl Ketene Dimer on the Physical, Mechanical, and Biological Durability of Plywood

“…Plywood is made of wood veneers bonded in an odd number of layers and is one of the most used wooden products in the construction and furniture industries (Ferreira et al 2017). Due to its structural properties, plywood has higher bending strength and screw holding capacity, and better physical properties than those of solid wood (Demir et al 2017).…”

“…Many efforts have been taken to improve the dimensional stability of wood-based panels (Filcock and Vinden 2000;Papadopoulos and Gkaraveli 2003;Hundhausen et al 2009;Ferreira et al 2017). For example, some researchers have reported that wood-based panels treated with isocyanate resin as a hydrophobic agent decreased the thickness swelling of wood-based composites (Filcock and Vinden 2000).…”

“…Thermal treatment is an ecologically friendly alternative treatment method used to improve dimensional stability. During the thermal treatment process, dimensional stability increases due to the reduction of hydroxyl groups in the hemicellulose, the most hydrophilic polymers of wood (Hill 2006;Ferreira et al 2017).…”

Painel híbrido OSB/MDP de madeira Pinus taeda e resina poliuretana à base de óleo de mamona

“…Estima-se que o aproveitamento da madeira em produtos finais, após seu processamento em serrarias, varie entre 40% e 60%, sendo os resíduos gerados, na maioria das vezes pó de serra, descartados de maneira indiscriminada (VIEIRA et al, 2010;OFOEGBU;OGBONNAYA;BABALOLA, 2014;SILVA et al, 2017;MONTEIRO et al, 2017;ALMEIDA et al, 2017 (CHIROMITO et al, 2016;RUZIAK et al, 2017;NASCIMENTO et al, 2017;FERREIRA;CAMPOS, 2017;SOUZA et al, 2018).…”