Eggshell bio-derived hydroxyapatite particle-wool/polyester staple fibers hybrid reinforced epoxy bio-composites for biomedical services

This study assessed the impact of hybrid reinforcement from natural and synthetic materials on the wear and mechanical properties of epoxy-based composite materials needed for biomedical applications. Hydroxyapatite was synthesized from eggshells using the hydrothermal method, while wool fiber was obtained from cow hair. The hybrid reinforced composites were developed by blending hydroxyapatite particles and the fibers by hand layup method in an open mold production process, with specified amounts of 3–15 wt % reinforcement. The characterized properties included tensile and flexural strengths, impact energy, wear resistance, and hardness. A scanning electron microscopy study was conducted to analyze the adhesion between the matrix and reinforcements at the interface, providing valuable insights into the overall integrity of the composites. The results showed a significant increase in the properties of the hybrid reinforced composites when compared with the pristine sample. In particular, the 6 wt% reinforced composite enhanced 61.14 % in tensile strength and 160.79 % enhanced 61.14 % in tensile strength and 160.79 % in flexural strength. Thus, the study shows that substituting synthetic fibers with hybrid organic-based reinforcement offers a viable approach for developing sustainable materials with improved mechanical properties suitable for biomedical applications.