Smart polymers for sustainable marine antifouling coatings – ECO-SmartAF

The ECO-SmartAF project aims to develop new sustainable and environmentally friendly marine antifouling coatings to reduce the carbon footprint of maritime transport. Our approach is to design smart coatings that combine contact activity with appropriate amphiphilic surface chemistry, both of which prevent the adhesion of marine organisms. Smart alkoxyamine-based monomers will be designed to prepare seawater and/or enzyme-responsive polymers to generate nitroxyl and alkyl radicals, active towards the targeted marine organisms. The well-known rapid degradation (a few microseconds) of the alkyl radical will prevent its bioaccumulation and its prolonged contact with marine species that could become resistant. New methacrylic graft copolymers composed of hydrophobic poly(dimethylsiloxane) and hydrophilic poly(ethylene glycol) side segments will be synthesized to impart an amphiphilic character to the coating surface. Seawater hydrolyzable trialkylsilyl ester-based (meth)acrylic monomers will be inserted to promote changes in surface properties with immersion. The chemical composition of copolymers will be tuned to promote the presence of alkoxyamine-based units at the coating surface. Copolymers will be used (i) as matrix in erodible coatings and (ii) as additive in silicone elastomer-based fouling release coatings. Effectiveness of newly developed coatings will be assessed both through laboratory and field assays, including different model species and environmentally dissimilar coastal immersion sites. A wide range of toxicity tests will be carried out on bacteria, artemia and microalgae to ensure that the new coatings are environmentally friendly. An ecotoxicological risk analysis will be performed on leachates using a recently developed marine cell culture model of oyster Crassostrea gigas immune cells.