Seawater-Induced Healable Underwater Superoleophobic Antifouling Coatings.

Creating an artificial surface, mimicking a live fish scale that repels oil underwater and with self-healing properties, would be significant for the development of nontoxic marine antifouling coatings. Here, we report a seawater-induced strategy to create in situ an underwater superoleophobic surface, starting from the coatings of a self-polishing polymer and seawater-responsive polymer-grafted SiO2 nanoparticles. The coatings' surfaces were able to renew in artificial seawater through the hydrolysis of the superficial self-polishing polymer and its subsequent dissolution. Particularly, the grafted poly(triisopropylsilyl acrylate-co-3-methacryloxypropyltrimethoxysilane) chains could transform into hydrophilic ones via seawater-induced hydrolysis, which additionally strengthened the oil repellency (zero oil adhesive force) and endowed the surface with excellent anti-protein adsorption characteristics. Because the hydrolysis was limited to the superficial layer of the coatings, it could avoid the water-swelling that instead occurs with conventional underwater superoleophobic coatings, with significant benefits to its durability. We believe that the seawater-induced renewal of underwater superoleophobic surfaces will be useful in extreme marine environments.