Reaproveitamento da madeira tratada com arseniato de cobre cromatado e isolador elétrico cerâmico para produção de compósito polimérico

Abstract

The reuse of materials is a topic of great interest due to the high amount of waste generated in various activities. Waste of treated wooden poles with chromated copper arsenate (CCA) and ceramic electrical insulators (RIP) are materials that could be re-used to manufacturing plastic timber. Such wastes are mainly generated from the maintenance of electricity distribution networks. In this work was studied the possibility of reusing this waste reinforcements agents for composites with high density polyethylene matrix (HDPE). The wood was ground in a knife mill and the RIP were ground in a ball mill. To obtain the specimens, HDPE, reinforcing agent and coupling agent were processed in a twin screen extruder and molded by injection. A 2k experimental design was developed to evaluate the influence of controllable factors on the response variables (flexural and tensile strength) and thus identify the optimal formulation composition to obtain the composite. After identifying the optimal formulation, the experimental design was validated and the mechanical, morphological, thermal, chemical, rheological and physical properties of the composite material were evaluated. In addition, leaching and solubilization tests were carried out to classify and evaluate possible applications for these composites. The addition of 20% of each strengthening in the matrix gave an increase up to 50% in the flexural and tensile strength compared to the pure HDPE. The micrographs corroborate with the results of mechanical properties, and it was possible to identify the interaction between the phases. The thermal analysis showed that the addition of reinforcements promoted the conservation of the mechanical properties of the composite in a higher temperature range than the HDPE. The chemical analyzes have identified the organic groups attached to each raw material in the composite composition and the changes due to degradation caused by exposure to accelerated aging in UV chamber. The leaching showed concentrations of As, Cu, Cr and Pb below the limits allowed by legislation, even after 3,024 hours of aging test, classifying the composite waste as non-dangerous, II-A class. Due to good matrix wettability to the reinforcements, the composite had low water absorption, low density and low moisture content. The accelerated aging showed small variations on the composite properties, unlike HDPE, which showed strong reductions in all its properties. Thus, to produce composites becomes an alternative to reuse these wastes, especially for applications in the energy sector, construction, architecture, and other industries, and promote waste management and reduce environmental impact.