Production and Characterization of Doum Palm Shell-Recycled Low-Density Polyethylene Composite as an Alternative Material for the Production of Crash Helmet

Abstract

The production of crash helmets is a critical aspect of ensuring the safety of individuals participating in various activities such as motorcycle riding, cycling, and extreme sports. Traditionally, helmets have been manufactured using materials that include polycarbonate, fiberglass, and carbon fiber. In recent years, there has been growing interest in exploring alternative materials for crash helmet production that are cost-effective and environmentally friendly. This study assessed the effects of integrating doum palm shell (DPS) particles into a composite material made from recycled low-density polyethylene (RLDPE). The study specifically addressed the impact, hardness, tensile, and flexural strength, and density of the particulate composite, and the influence of particle size and loading was also assessed. RLDPE and DPS particles were compounded using a two-roll mill and molded by compression molding to create the composites. Two particle sizes of DPS (150 µm and 300 µm) were used to prepare eight different composite formulations, which were tested to analyze their response to mechanical loads. The specimen with the optimum desirable mechanical properties for helmet application was found to be 95 wt% RLDPE and 5 wt% DPS (150 µm), with an impact strength of 66.67 kJ/m², flexural strength of 162.60 MPa, tensile strength of 18.4 MPa, hardness value of 16 HV, and density of 0.88 g/cm³. The results were compared with past literature and found to be considerably suitable