Effect of board density and adhesive combination on physical and mechanical critical properties of OSB made with Chilean native wood

Abstract

The aim of this study was to evaluate the effect of board density and adhesive combinations on physic-mechanical properties of industrial scale structural OSB (oriented strand board) made only of strands from Chilean native wood (Nothofagus dombeyi (coigüe), Nothofagus alpina (raulí) and Nothofagus obliqua (roble)). These boards were tested to fulfill the quality standards of the certifier organism "Engineering Wood Association" (APA), since presently they are not being reached. It compared Chilean native wood OSB with common OSB (50% native and 50% Pinus radiata wood) as a control. The effect of two densities (700 kg m^-3, 640 kg m^-3) and four combinations of adhesive (phenol formaldehyde, FF, in the faces and methyl di - isocyanate, MDI, in the core) over the physical and mechanical properties (concentrated static load, dry flexion, cycled humid flexion and linear expansion) was analyzed. The density was the variable with higher incidence on the properties; 700 kg m^-3 OSB had better physical and mechanical behavior than that presented by 640 kg m^-3 OSB. We identified an optimal production treatment according to quality standards and physic-mechanical properties. The studied OSB did not show significant differences compared to the control OSB. Finally, it is possible to make certified OSB using Chilean native wood.