Polyurethane antifouling coatings with various antifouling strategies in the side chain

Marine fouling is a major barrier to the further development of the marine industry. As science and technology progress, the antifouling coating is still difficult to exhibit feasible and effective strategies against multiple fouling organisms by simple modification. This study reports a polyurethane coating consisting of quaternary ammonium and zwitterions via modifying the imidazole on the side chain, where the former exhibits fouling-degrading performance to kill the bacteria sufficiently, and the latter relies mainly on the formation of the hydrated barrier that could present superior rejection of protein and algae due to the fouling-resistant property. By controlling the number of different antifouling groups in the side chain, the antifouling strategies can be adjusted to deal with marine pollution in different environments. The modified coating could expose hydrophilic and hydrophobic groups on the surface, which produce micro/nano structures underwater. The comprehensive antifouling properties of the coating makes it have a promising future in marine antifouling.