Particleboards based on agricultural and agroforestry wastes glued with vegetal polyurethane adhesive: An efficient and eco-friendly alternative.

This research aimed to evaluate particleboards produced with bean straw and rubberwood particles glued with vegetable polyurethane adhesive as a proposal for a sustainable insulating material. Therefore, the physical, chemical, and mechanical properties of the panels were determined, as well as their resistance to termite attack, combustibility, and thermal insulation. By increasing the bean straw particle content, the water absorption was significantly reduced (from 11.44 % to 7.68 %), with the same tendency observed for thickness swelling (from 4.61 % to 1.73 %) after 24 h of immersion. Panels produced with 25 and 75 % bean straw contents showed an end to thermal degradation before rubberwood-only compounds, being more resistant to combustion. There was a reduction in the modulus of elasticity (66.4 %) and modulus of rupture (52.5 %) due to the increase in the bean straw particle content. The evaluation of the resistance of the particleboard to dry wood termites showed a lower mass loss for composite panels with higher contents of bean straw. The thermal conductivity of particleboards showed that greater amounts of waste resulted in greater thermal insulation. In terms of generating sustainable products and meeting the needed properties, it was concluded that it is feasible to produce particleboards with agricultural wastes and formaldehyde-free adhesive. • Bean wastes were used as a substitute for rubberwood in particleboards. • Particleboards with environmentally friendly castor oil-based adhesive were studied. • The chemical properties of bean wastes influenced the properties of particleboards. • The thermal insulation of the panels improved with higher waste levels. [ABSTRACT FROM AUTHOR]