Physical-mechanical properties of plywood with <i>Cupressus lusitanica</i> Mill. wood

Abstract

The quality of wood from the species Cupressus lusitanica Mill. has been explored for the most diverse purposes in recent research, in view of the growth potential already reported for it in the literature, which makes it an option for diversifying the sources of supply of the timber industry in the southern region, currently dependent on few conifer species such as Pinus elliottii and Pinus taeda. This research aimed to evaluate the physical-mechanical properties of plywood panels made with Cupressus lusitanica wood veneers and its combination with P. taeda wood and to compare the results obtained with panels made only with P. taeda and also with the minimum requirements stipulated by the National Wood Quality Program for Pine plywood. Panels with 17 mm thickness, glued with phenolic resin in the weighing of 328 g/m², were evaluated regarding the physical properties of specific mass, moisture content, water absorption, thickness swelling and regarding the mechanical properties in parallel static bending and perpendicular. Thickness swelling did not differ between the evaluated treatments, although they did show differences in terms of water absorption and apparent specific mass at 12% moisture. For the parallel static bending test, the plywood made only from P. taeda wood showed greater stiffness, however an increase in resistance was observed in the combination of this wood with C. lusitanica. Regarding the perpendicular test, the combination of wood from P. taeda and C. lusitanica promoted mechanical properties equivalent to panels of traditional use (P. taeda). The use of the C. lusitanica species and its combination with the P. taeda species proved to be promising in terms of the evaluated physical properties and, in terms of mechanical properties, resulted in lighter panels and resistance equivalent to that registered for panels of P. taeda.