Cation-indole supramolecular interaction constructed novel silicone anti-fouling materials

Due to the limited static antifouling properties of silicone materials, their application in the marine field has been restricted. Chemical grafting antifouling agents onto matrix is an effective approach to enhancing this ability. Indole and its derivatives have garnered significant attention in marine antifouling due to their antibacterial, anti-UV and fluorescence properties. In this study, indole groups were introduced into the side chain of siloxane, and a novel silicone material was constructed utilizing cation-indole supramolecular interactions for the first time. As the constructed non-covalent cross-linked network, the maximum stress of materials could reach to 1.0 MPa, and the strain was up to 200 %. Furthermore, the materials exhibited self-healing capabilities at 60 degrees C for 9 h with a healing efficiency of 99 %, and could be fully recovered by solvent and hot pressing. As the coating materials, they effectively shielded ultraviolet light while maintaining a transmittance of 80 % in the visible region. The presence of indolyl group contributed to an inhibition rate 97.59 % against Escherichia coli and 93.75 % against Staphylococcus aureus. Additionally, the materials achieved a synergistic antifouling mechanism combining fluorescence and contact antibacterial effects. This study provided a new method for constructing silicone materials with potential applications in marine antifouling.