ZnO/Acrylic Polyurethane Nanocomposite Superhydrophobic Coating on Aluminum Substrate Obtained via Spraying and Co-Curing for the Control of Marine Biofouling

Biofouling is a costly and complex problem in the marine industry. Traditional anti-biofouling coatings based on the release of biocidal substances have caused serious environmental and health issues. Polymeric nano composite superhydrophobic coatings have attracted increasing attention worldwide as durable and ecofriendly alternatives to toxic anti-biofouling paints. However, the conventional procedures for preparing nanocomposite coatings still have some drawbacks. In particular, the nanoparticles on the surface of the coating are buried in the matrix resin, which greatly diminishes the anti-biofouling properties of the coating. To overcome these problems, in this paper a facile spraying and co-curing method was adopted to construct a superhydrophobic coating using acrylic polyurethane and a hydrophobic ZnO bactericidal suspension. The obtained coatings displayed excellent superhydrophobicity, robust abrasion resistance, and high stability in practical operation. Moreover, the synergistic effects of the ZnO bactericidal nanoparticles and the superhydrophobic coating are able to suppress marine algae adhesion and biofilm formation. Hence, the developed nanocomposite superhydrophobic coating can be applied as an effective anti-biofouling agent for applications in marine environments.