Improvement of water absorption behavior and mechanical properties of woven jute fiber‐reinforced epoxy composites with waste eggshell filler

Abstract The need for renewable and biodegradable materials has emerged in the last few decades with the awareness of environmental issues and that has led to increased interest in natural fiber‐reinforced composites. Jute fibers, known for their versatility, are abundant, cost‐effective and biodegradable. However, their use is limited by challenges such as low compatibility with polymer matrices and high water uptake. Introducing waste eggshell filler offers a promising solution to enhance mechanical properties and reduce water absorption, while also addressing bio‐waste disposal. This study investigates the impact of eggshell powder fillers on the water absorption and mechanical properties of plain‐woven jute/epoxy composites fabricated via vacuum infusion. Composites with filler ratios ranging from 0 to 5 wt% were subjected to water absorption tests using tap, distilled and saline water, and mechanical tests (tensile, flexural, impact and hardness) under dry and wet conditions. Results indicated that eggshell fillers, up to a 3 wt% ratio, reduced water absorption, with distilled water showing the highest absorption across all samples. Mechanical testing revealed that a 2 wt% filler ratio yielded the optimal performance, exhibiting the highest tensile, flexural and impact strengths in dry conditions, attributed to enhanced load distribution and fiber–matrix bonding. Water immersion significantly deteriorated mechanical properties in all composites, though eggshell fillers mitigated this effect, particularly at 2 wt%. However, filler ratios exceeding 3 wt% led to decreased mechanical performance, likely due to filler agglomeration. This study demonstrates that eggshell powder, a bio‐waste, effectively enhances the water resistance and mechanical strength of jute/epoxy composites, with a 2 wt% filler ratio proving optimal for improved composite performance. © 2025 The Author(s). Polymer International published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.