Properties of particleboards manufactured from bamboo (Dendrocalamus asper)

Bamboo is a source of industrial raw material with wide geographical distribution. Brazil has good soil and climate conditions for its cultivation, in addition to existing reserves. Advantages of bamboo include: versatility, fast growth and good strength properties. One way of using this material would be as a raw material for manufacturing particleboards. Within this context, this article addresses an evaluation of the physical and mechanical properties of particleboards manufactured from bamboo particles (Dendrocalamus asper (Schult f.). Backer ex Heyne. Particles with 0.50 and 0.85mm granulometry and two conditions (control and treatment by immersion in hot water (70 +/- 5 degrees C) for two hours) were used. Twelve homogeneous particleboards bonded with urea-formaldehyde adhesive with 10% solids were manufactured and the predetermined nominal density for all panels was 650 kg m(-3). The properties analyzed were: water absorption, swelling and non-return rate in thickness, density profile, rupture modulus, elastic modulus, screw withdrawal and internal adhesion. Panels consisting of 0.50 mm granulometry showed higher water absorption rates, while panels made of particles treated with hot water and 0.85 mm granulometry showed higher swelling rates and non-return thickness. The panels made of treated particles showed higher density profile values in both layers of the panels. The granulometry did not influence the mechanical properties of the panels, and those with treated particles exhibited significant performance for the surface and top screw withdrawal properties, and internal adhesion. This last mentioned property reached the minimum value required by the standard. The results showed that it is feasible to use bamboo to manufacture particleboards, but it is necessary to adjust some variables such as nominal density, pressing parameters, adhesive content or the inclusion of a less dense material in the composition of the panels.