Production and analysis of the physical and mechanical of particleboards panels produced with Acrocomia aculeata endocarp

Abstract

Background: The macauba (Acrocomia aculeata (Jacq.) Lodd. ex Mart.) is a palm tree native to tropical regions and occurs in much of the Brazilian territory. Current studies are focused on the extraction and exploitation of vegetable oil from this fruit. However, there are few studies on the residue, the endocarp, which represents approximately 25% of the total mass of the fruit. Studies that search for solutions for using residue, thus adding value, and generating environmentally friendly products, are of fundamental importance.  Thus, this research aimed to evaluate the physical and mechanical properties of reconstituted wood panels produced with different proportions of macauba endocarp particles to replace pine wood particles, in addition to characterize the physical and chemical properties of macauba endocarp. The chemical characterization tests were performed according to applicable standards. The basic density was determined according to the NBR 11941 standard. Thermogravimetric analysis (TGA), X-ray diffractometry (XRD) and Fourier transform infrared spectroscopy (FTIR) were also performed. The particleboards panels were produced with a nominal density of 0.70g/cm³ and dimensions of 25x25x1.5cm. Five different treatments were evaluated with variations in the proportion of macauba endocarp particles in the core of the panel. For particle agglutination, phenol-formaldehyde adhesive was used at a proportion of 9% for the core and 12% for the faces, based on the dry mass of each panel. Scanning electron microscopy (SEM) was used to analyze the panel surfaces.

Results:The endocarp of Acrocomia aculeata has low extractive content, high lignin content and high densification, 1.23g/cm³, when compared to Pinus oocarpa wood, 0.43g/cm³. All panels were classified as low density according to CS 236-66 and had an average apparent density between treatments of 0.586g/cm³. A greater dimensional stability and a decrease in the static bending properties of the panels was observed as the proportion of macauba endocarp particles increased. The internal bonding of the panels showed a positive result with the increase in the use of particles of the residue.

Conclusion: The panels produced have potential for use for non-structural purposes.