Construction and tribological properties of poly acrylic acid‐poly(3‐(methacryloylamino)propyl) dimethyl(3‐sulfopropyl)ammonium hydroxide hydrogel coatings embedded with SiO₂ nanoparticles on Ti6Al4V substrate

The development of highly effective bio‐lubricant coatings for arthritis treatment is extremely demanded. Herein, inspired by the efficient lubrication of articular cartilage, acrylic acid (AA) with (3‐(methacryloylamino) propyl) dimethyl (3‐sulfopropyl) ammonium hydroxide (MPDSAH) hydrogel coatings containing nanoparticles on Ti6Al4V substrate were designed and fabricated via UV grafting technology. SiO 2 and SiO 2 grafted with PAA polymer brushes (SiO 2 ‐g‐PAA) were separately doped into the PAA‐PMPDSAH hydrogel. The PAA‐PMPDSAH/SiO 2 ‐g‐PAA exhibits good tensile and compressive properties compared with PAA‐PMPDSAH/SiO 2 hydrogel, with an enhancement of 183.4% in tensile modulus and 60.8% in compressive modulus. The PAA‐PMPDSAH/SiO 2 ‐g‐PAA hydrogel coatings exhibit a low wear volume, 2.9 ± 0.16 × 10 6 μm 3 , representing a decline of 32.1% and 61.3% compared with the PAA‐PMPDSAH and PAA‐PMPDSAH/SiO 2 hydrogel coatings, respectively. The antiwear performance has obviously improved. The hydrophilic PAA polymer brushes prevent the agglomeration of nanoparticles and promote homogeneously dispersion within the hydrogel. The three‐dimensional crosslinked network structure of hydrogel effectively protects the structural integrity of the polymer brushes, thereby facilitating enduring lubrication properties. This work provides a strategy for promising artificial joint lubrication in biomedical fields.