An investigation on elastic modulus of novel nanoparticle enhanced polyetheretherketone implant biocomposite.

Background: Polyetheretherketone (PEEK) shows promise as a biocompatible implant material, but its low elastic modulus necessitates reinforcement. This study explores the potential of Azadirachta indica (neem) leaf nanoparticles as eco-friendly reinforcements to enhance polyetheretherketone's (PEEK) elastic modulus for orthopedic and biomedical applications. Materials and Method: Neem leaves were processed into 100-175 nm Azadirachta indica nanoparticles (AINP) via ball-milling. AINP-reinforced polyetheretherketone (PEEK) composites (0, 10, 15, 20 wt%) were prepared using injection molding. Nanoindentation experiments evaluated elastic modulus, with statistical analysis (one-way ANOVA, Tukey test) performed to assess the effects of AINP reinforcement. Results: Nanoindentation experiments revealed significant enhancements in elastic modulus (E) with Azadirachta indica nanoparticle reinforcement. Elastic modulus increased from 1.38 GPa (0% reinforcement) to 2.52 GPa (20% reinforcement), representing an 82.61% increase. ANOVA and Tukey tests confirmed statistically significant differences between unreinforced and reinforced groups (p=0.000), but no significant improvements beyond 20% reinforcement. Conclusion: The incorporation of Azadirachta indica nanoparticles into PEEK enhances and matches the elastic moduli to human bone, rendering it a suitable candidate for replacing traditional metallic implants in orthopedic and dental applications.