Valorization of Waste LDPE Using Isoberlina Wood Fillers: Mechanical Properties, Creep Resistance, and Dynamic Viscoelastic Behavior of Sustainable Composites

Abstract

In an effort to develop eco-conscious technologies for waste reduction, this study explores the potential of Isoberlina wood fibre (IWF) as a reinforcing agent in recycled low-density polyethylene (rLDPE) composites, aiming to enhance mechanical performance while promoting sustainable reuse of plastic waste. Using standardized mechanical testing, dynamic mechanical analysis (DMA), and creep evaluation, the influence of IWF on the composite’s structural and viscoelastic properties was evaluated. At 20 wt% fibre content, the rLDPE composite exhibited significant improvements: tensile strength (11.5 MPa), elastic modulus (167 MPa), flexural strength (70.4 MPa), and Shore hardness (68). DMA results revealed a substantial increase in storage modulus from 330 MPa to 1.2 GPa, indicating enhanced load-bearing capacity. A decline in loss modulus with increasing temperature and frequency suggested reduced energy dissipation and improved stiffness. Creep analysis demonstrated a lower strain rate over time, with the reinforced composite reaching equilibrium at 38.1 minutes, outperforming the unreinforced rLDPE polymer and confirming improved resistance to long-term deformation. These results underscore the effectiveness of Isoberlina fibre in enhancing the mechanical, thermal and creep performance of rLDPE, offering a viable pathway for eco-friendly composite development.