Optimizing epoxy composites with Ca(OH)₂-treated durian peel fibers: Mechanical and fire-retardant insights

This study focuses on enhancing the mechanical properties and flame retardancy of epoxy composites by incorporating durian peel fiber (DPF) treated with an eco-friendly chemical method using a Ca(OH)₂ suspension solution at three different concentrations (1.0%, 2.0%, and 3.0% w/v). The composite samples (DPF-1, DPF-2, and DPF-3) were evaluated through mechanical tests (tensile strength, flexural strength, compressive strength, and Izod impact strength) and flame resistance tests, including LOI (Limiting Oxygen Index) and UL 94HB (Horizontal Burning Test). The results indicate that DPF-2 (2.0% Ca(OH)₂) exhibits the best overall properties, with a densely packed char layer after combustion, reducing flame propagation. Higher Ca(OH)₂ content (3.0%) led to uneven fiber expansion, lowering some mechanical properties. The LOI and UL 94HB results of DPF-2 also demonstrated significantly improved flame retardancy. Research on the chemical treatment of durian peel fibers using green chemicals (Ca(OH)2) to protect the environment. Improving the efficiency of applying natural fibers from industrial waste in the fabrication of potential composite materials for structures in the automotive, construction and aerospace industries with sustainable value.