Valorization of recycled plastic in the production of biocomposites reinforced with residues from the cotton agroindustry

Abstract

The production of composites, using waste materials as matrix and reinforcement, is an innovative, environmentally relevant, and economically viable alternative, regarding the environmental problems generated by inappropriate disposal. This study aimed to produce and characterize the technological properties of composites based on low-density polyethylene produced by extrusion with proportions of 0, 10, 20, 30, and 40% of cotton-seed cake residue (reinforcement) replacing the polyethylene mass (matrix). The composites were characterized for their physical–mechanical and morphological properties. The inclusion of cotton residue promoted an increase in moisture, from 0.05 to 0.37%, in water absorption 24 h (0.05 to 1.2%) and in thickness swelling (0.8 to 2.1%). The composites density did not show significant variation with the increase in the waste content. Regarding the mechanical properties, there was a decrease of 28, 52, and 81% for the modulus of elasticity, tensile, and tenacity, respectively. The results were similar when compared to other residual composites. In this way, it was possible to give a correct destination to the waste of low-density polyethylene and cotton-seed cake, producing a final material with high added value.