Caracterizacąõ tecnológica de paineís particulados produzidos com resíduos de cinco espécies tropicais

Abstract

The objective of this study was to characterize technologically particleboards produced from the processing residues of five commercial tropical species: angelim (Hymenolobium sp/Andira sp), cambará (Qualea sp), canelaõ (Nectandra sp/Ocotea sp), cedar (Cedrelinga cateniformis) and itaúba (Mezilaurus itauba). Three panels of each species and also three panels with the mix of the five species in equal proportions (mix) were made, resulting in 18 panels with nominal density of 0,65g/cm. The panels were composed of 12% of urea formaldehyde resin and 1% wax emulsion. The press cycle used was of 160°C temperature and pressure of 40 kgf/cm for 8 minutes. The data were submitted to the analysis of variance and Tukey test (95% of reliability). All wood species except for cedro presented higher densities and lower compression ratios than the intervals cited in the literature. This was reflected in the lower values of resistance and stiffness. All panels presented good results for the dimensional stability. The species angelim, cambara and canelaõ presented promising results. Cedro, although with higher compression ratio; did not show mechanical results in the same magnitude, except for internal bond. The incorporation of species with lower wood densities is recommended, as well as the control of the particles granulometry and the increase of the panels' nominal density.