Research on the Marine Antifouling Ability and Mechanism of Acrylate Copolymers and Marine Coatings Based on a Synergistic Effect

Marine biofouling is an urgent global problem in the process of ocean exploitation and utilization. In our work, a series of zinc-based acrylate copolymers (ACZn-x) were designed and synthesized using benzoic acid, zinc oxide (ZnO) and a random quaternion copolymer consisting of ethyl acrylate (EA), butyl acrylate (BA), acrylic acid (AA) and methacrylic acid (MAA) by free radical polymerization and dehydration condensation. The ACZn-x with a zinc benzoate side chain is able to hydrolyze in natural seawater under static conditions, resulting in the formation of a smooth surface. We investigated and confirmed the antifouling (AF) behavior of ACZn-x in the laboratory and revealed that they have better antibacterial (86% for S. aureus and 72% for E. coli) and anti-algal (≥ 60.1% for N. closterium and ≥ 67.5% for P. subcordiformis) activities. We also assessed the marine AF properties of ACZn-x and corresponding coatings in Qingdao, China; the ACZn-x exhibited ideal AF properties with little silt and biological mucosa adhered to the ACZn-x surface after 6 months, and corresponding coatings exhibited little biofouling after 16 months in the ocean. Importantly, possible AF mechanisms were further proposed at the cellular level. These results could be helpful for the development and application of effective AF coatings.