Mechanical and tribological properties of poly(hydroxyethyl methacrylate) hydrogels as articular cartilage substitutes

► In this study we obtained a HEMA hydrogel substitute of articular cartilage. ► Hydrogels with different amounts of hydrophilic monomer were synthesized and tested. ► HEMA-5%AA hydrogel has mechanical properties similar with the articular cartilage. ► Increase in %AA decreases the homogeneity of hydrogel at macro and nanoscales. ► The HEMA hydrogels exhibit a similar cartilage boundary lubrication mechanism.