Tribological characteristics of polyvinylpyrrolidone (PVP) as a lubrication additive for artificial knee joint

The effect of polyvinylpyrrolidone (PVP) on tribological properties of joint prostheses is still unclear despite its good lubricity and biocompatibility. PVP solutions with five concentrations were prepared with two different solvents. The viscosity, surface tension, and static contact angle of the solutions were measured as well as the friction coefficient and wear volume of artificial joint pairs. With PVP concentration increasing, the friction coefficient firstly decreased significantly but subsequently tapered off after a high level. The inclusion of PVP also improved the wear resistance of the pair. It implies that PVP could be a promising lubrication additive for artificial joints.