Multimaterial Synergy in Bioactive Polyetherketoneketone (PEKK) Composites for Advanced Skeletal Reconstruction

ABSTRACT

Polyetherketoneketone (PEKK) is a high‐performance thermoplastic polymer with bone‐mimetic mechanical properties and radiolucency, making it a promising alternative to conventional metallic orthopedic implants. However, its inherent bio‐inertness limits effective osseointegration and antibacterial performance. The present investigation reports the fabrication of novel multifunctional PEKK‐based composites incorporating bioactive ceramics such as hydroxyapatite (HAp), tricalcium phosphate (TCP), and bioactive glass (BAG), as well as antibacterial metal oxides (ZnO and CuO). These composites were fabricated using the melt compounding process and hot‐compression molding, followed by characterization of their physicochemical, mechanical, and biological properties. These composites exhibited high densification (98%–99%) and significantly enhanced surface wettability, with water contact angles decreasing from 84° for pure PEKK to 71°–79° for the PEKK composites. Mechanical performance was also significantly enhanced, with the elastic modulus increasing from 4.46 ± 0.04 GPa to 5.56 GPa and hardness increasing from 254.76 ± 7.83 MPa to 376.66 ± 5.72 MPa, while maintaining a compressive strength of ∼211–233 MPa. In vitro biological assessment confirmed improved cell proliferation, extracellular matrix production (Collagen‐I) and mineralized matrix deposition (Ca/P), indicating the fabricated composites accelerated bone cell formation (osteoblasts). Furthermore, CuO‐incorporated composites showed strong broad‐spectrum antibacterial activity against Escherichia coli and Staphylococcus aureus (∼81%–82% inhibition) and a significantly reduced bacterial colony formation (CFU). Overall, this study demonstrates that the combined integration of bioactive HAp, TCP, BAG, and antibacterial ZnO and CuO can effectively transform bio‐inert PEKK into an infection‐resistant implant. This novel composite offers a promising strategy for the development of next‐generation load‐bearing orthopedic implants with enhanced osteoconductivity and improved long‐term clinical performance.