Fabrication of an anti-fouling coating based on epoxy resin with a double antibacterial effect via an in situ polymerization strategy

The hull and subsea equipment are often plagued by widespread marine biofouling, so developing a sustainable environmental protection antifouling paint is urgent. The study designed and developed an antifouling composite coating system (E44-Ag-PGI) with a synergistic antibacterial effect based on the dual strategy of the bacteriostatic effect of stereochemical structure on polymer surface and release sterilization of metal nanoparticles. Firstly, an antifouling agent (PGI) was prepared by simple radical polymerization by combining glycidyl methacrylate with borneol, a complex bicyclic monoterpene structure extracted from plants. Then bisphenol A epoxy resin with strong adhesion to metal was selected as the base material. The synthetic antifouling agent with epoxy groups was polymerized in situ into the epoxy resin network, and compared with pure epoxy resin, the elongation at break of E44-Ag-PGI coating with 20 % PGI content increased from 40.37 % to 124.8 %, which was mainly attributed to the introduction of a soft chain of antifouling agent polymer, which improved the flexibility of the coating. Meanwhile, the antibacterial efficiency of the coating against Pseudomonas aeruginosa and Staphylococcus aureus was 97.69 % and 95.9 %, respectively. This excellent antibacterial performance was mainly attributed to the synergistic antibacterial action of natural borneol and AgNPs. In addition, the biofilm and diatom resistance experiments of the coating showed that the coating also has an excellent antifouling effect. This provided a new research idea for environmentally friendly antifouling coatings.