Effect of irradiation dose on mechanical and biotribological properties of PVA/PVP hydrogels as articular cartilage

• Hydrogels were prepared by freezing–thawing followed by gamma-ray irradiation.
• Hydrogels treated with irradiation dose of 100 kGy had the best mechanical properties.
• The intrinsic properties of counterface material affects the friction coefficient.
• Hydrogel-on-stainless steel contact has the lowest friction coefficient.

Poly(vinyl alcohol)/poly(vinyl pyrrolidone) (PVA/PVP) hydrogels were prepared by freezing–thawing followed by gamma-ray irradiation with the doses of 50, 100 and 150 kGy and their mechanical properties were studied. The effects of irradiation dose and counterface material on the tribological properties of hydrogels were investigated by rubbing against stainless steel, UHMWPE, and PVA/PVP hydrogel itself. The results show that the mechanical and tribological properties of hydrogels significantly depend on the irradiation dose. Hydrogels treated with irradiation dose of 100 kGy show the best mechanical properties and the lowest friction coefficient. The intrinsic properties of counterface material influence the friction coefficient of system. The friction coefficient of PVA/PVP hydrogel against stainless steel is lower than that against UHMWPE and hydrogel itself.