“From The Nature for The Nature”: An Eco-friendly Antifouling Coating Consisting of Poly(lactic acid) Based Polyurethane and Natural Antifoulant

“From the nature, for the nature” is an instructive strategy to develop environment-friendly antifouling coatings. In this work, bio-sourced poly(lactic acid) based polyurethane with hydrolyzable triisopropylsilyl acrylate (TSA) side groups has been prepared via thiol-ene reaction and polyaddition. Such a polymer exhibits high adhesion strength (~2.0 MPa) and a controlled degradation rate tuned by varying its soft segment and TSA content. An environment-friendly coating is prepared with the polymer and an eco-friendly antifoulant (butenolide) derived from marine bacteria. Our study shows that butenolide can be released from the coating in continuous manner with a controlled rate as the polymer degrades in seawater. Digital Holographic Microscopy (DHM) tracking analysis demonstrates that the coating can effectively inhibit the adhesion of marine bacteria Pseudomonas sp.. Marine field test shows such coating has excellent antifouling ability for more than 3 months.