Hydrophilic microparticle reinforced polycarbonate-urethane for hydration lubrication in artificial joint applications

Polycarbonate-urethane (PCU), a versatile polymer distinguished by its remarkable mechanical robustness and superior biocompatibility, has garnered significant attention as a potential material for joint replacement implants. However, its suboptimal wettability in aqueous environments leads to elevated friction and wear under wet tribological conditions, limiting long-term clinical performance. Herein, a novel strategy to address this challenge by incorporating crosslinked polyvinyl alcohol (PVA) microparticles into PCU was proposed. The hydrophilic PVA microparticles enhance surface wettability and establish a robust hydration layer, significantly improving boundary lubrication. Remarkably, even at a minimal loading of 0.3 wt% PVA microparticles, the composite demonstrates a friction coefficient of 0.117 and a specific wear rate of 1.01 × 10 –6  mm 3 /N·m in calf serum, representing reductions of 68.8% and 90.3%, respectively, compared to pristine PCU. Furthermore, the composite retains outstanding tensile strength (36.6 MPa) and elongation at break (2528.7%), while exhibiting excellent biocompatibility. These findings suggest that the material holds potential for artificial joint applications, with improved durability and promising lubrication performance.