DEVELOPMENT OF NANOCOMPOSITES OF LINEAR LOW-DENSITY POLYETHYLENE AND REDUCED GRAPHENE OXIDE FOR THE ROTOMOLDING INDUSTRY

The optimization of dispersion and compatibilization processes is fundamental to maximizing the benefits of polymeric nanocomposites and making them a viable and economical alternative for various industrial applications. Therefore, this work investigates the effect of reduced graphene oxide (rGO) to improve the mechanical and thermal properties of Linear Low-Density Polyethylene (LLDPE). Samples with different concentrations of rGO and compatibilizing agent were obtained from a concentrate by melt processing using a twin-screw extruder. After injection molding, the nanocomposites were characterized by scanning electron microscopy, flexural and impact tests, and thermal analyses. The results showed improvements in mechanical properties, with an 11% increase in flexural strength, independent of rGO concentration. For the sample containing 0.05% rGO, a 17% increase in the elastic modulus was observed, evidencing the reinforcing effect of rGO particles, without losses in toughness. With the addition of the compatibilizing agent, the sample containing 0.05% rGO also showed greater thermal stability, with a 16 °C increase in the maximum degradation temperature compared to pure LLDPE. The addition of rGO and the compatibilizing agent did not promote changes in the melting temperature and crystallinity content of the nanocomposites. However, the crystallization temperature increased by up to 4°C with the addition of the highest amount (0.2%) of rGO. This result can be attributed to the nucleating effect achieved when a good level of distribution is achieved, as observed in the scanning electron micrographs, especially in the presence of the compatibilizing agent. Therefore, based on the results observed so far, it is expected that the developed nanocomposites have the potential for further use in the rotomolding industry, aiming to expand its range of applications.