Analysis of the Mechanical Properties of Polymer Composites Reinforced with Charcoal Particulate

Naturally reinforced polymer composites have emerged as a promising sustainable alternative to conventional polymers due to their biodegradability. This study aimed to develop a composite by incorporating charcoal particulate into a recycled high-density polyethylene (HDPE) matrix and evaluating its mechanical properties. Two manufacturing methods (compression molding and extrusion) and four charcoal concentrations (0, 5, 10, and 15%) were investigated. Characterization involved tensile tests and non-destructive evaluation using wave propagation and ultrasound techniques. The experiment followed a completely randomized design with a 4 × 2 factorial arrangement, comprising eight treatments. Statistical analysis was conducted using Tukey's test for multiple comparisons. The tensile test results indicated that the manufacturing methods of compression molding and extrusion led to significant differences in the elastic modulus (MOE) variable, in contrast to the results observed for the maximum stress variable. However, the addition of charcoal particulate caused a notable reduction in maximum tensile strength (approximately 50%), from 20.17 to 11.19 MPa, and a 22% decrease in the MOE, from 310.93 to 242.88 MPa, compared to unreinforced HDPE. Non-destructive testing confirmed the tensile test findings, also indicating a reduction in MOE. Despite the decline in mechanical properties, these composites remain viable for applications prioritizing lightweight structures, thermal insulation, or chemical resistance. Furthermore, their use enhances the valorization of waste and increases sustainability by reducing environmental impact.