Synergistic antifouling coating based on PS-b-PDMS/CaO2 for marine aquaculture nets

Biofouling on marine aquaculture nets poses significant challenges to the economic viability and environmental sustainability of mariculture. This study developed a novel composite coating PS- b -PDMS/CaO 2 on the net surface by incorporating oxygen-releasing calcium peroxide nanoparticles (CaO 2 NPs) into a polystyrene-polydimethylsiloxane block copolymer (PS- b -PDMS). This coating synergistically combines low surface energy with a sustained oxygen-enriched microenvironment and enhanced reactive oxygen species (ROS) generation, resulting in significantly enhanced antifouling performance. Experiments demonstrated that the coating achieved outstanding antifouling efficacy, with antibacterial rates exceeding 99% against Escherichia coli, Staphylococcus aureus, and the marine bacterium Pseudomonas aeruginosa, anti-diatom adhesion rates of 92.18%, and anti-protein adhesion rates of 96.82%, with an optimal loading of 0.6 wt%. Moreover, the coating improved the mechanical properties (~ 35.53 MPa) while preserving the low-surface-energy characteristics and sustained oxygen release for over 60 h. A 90-day marine field test verified minimal biological fouling on the PS- b -PDMS/CaO 2 -0.6 coating surface, showing excellent real-sea antifouling performance and structural stability, indicating the long-term serviceability of aquaculture nets in marine environments. This study proposes a novel technical pathway for the development of environmentally friendly, long-term stable, and high-performance antifouling and antibacterial coatings that can effectively adapt to complex marine environments. Graphical abstract