A new titanium dioxide-polyethylene glycol hydrogel for marine antifouling coatings

To address the issue of insufficient mechanical properties in conventional hydrogels that limit their marine antifouling applications, we innovatively proposed a construction strategy of titanium dioxide (TiO 2 ) nanoparticles reinforced polyethylene glycol (PEG) hydrogels. The TiO 2 -PEG hydrogel with uniformly dispersed nanoparticles were successfully prepared by in-situ polymerization, and the material showed excellent mechanical properties. When the content of TiO 2 is 0.5 wt.%, the tensile strength of the TiO 2 -PEG hydrogel can reach 0.97 MPa, which is 68.5% higher than that of the PEG hydrogel. CLSM analysis shows that TiO 2 nanoparticles effectively enhance the mechanical properties of hydrogels by inducing crack deflection and energy dissipation mechanism. Notably, TiO 2 -PEG hydrogel also has a broad-spectrum antifouling performance, which can effectively resist protein adsorption and adhesion of Escherichia coli, Staphylococcus aureus and diatoms. The structure-property relationship demonstrated that TiO 2 enhanced the TiO 2 -PEG mechanical properties, which inhibited its detachment from the substrate and thereby significantly improved the antifouling durability. This study not only provides new ideas for the design of high-performance marine anti fouling materials, but also provides theoretical basis and practical support for achieving synergistic enhancement of anti fouling performance and mechanical performance. • Innovative fabrication of TiO 2 -PEG nanocomposite hydrogels. • TiO 2 content of 0.5 wt.%, the hydrogel achieves a tensile strength of 0.97 MPa, demonstrating excellent mechanical properties. • TiO₂ improves hydrogel mechanics via crack deflection and energy dissipation. • TiO 2 -PEG hydrogels exhibit broad-spectrum antifouling properties.