Improving the properties of antifouling hybrid composites: The use of Halloysites as nano-containers in epoxy coatings

Marine biofouling is an age-old problem with a broad impact in many marine activities. The development of environmentally friendly and long-term marine antifouling coatings remains a huge challenge in the maritime industry and involves many factors: hydrophobicity, surface roughness, electrostatic interactions, and the use of anti-adhesive/biocide molecules. We developed a novel antifouling epoxy paint doped with Halloysite clay nanotubes (HNTs) as nano-containers. HNTs were loaded with two eco-sustainable antifouling molecules, sodium salicylate and N-(2,4,6-trichlorophenyl)maleimide, which can dramatically reduce bacterial attachment. The dispersion procedure of the nano-carriers in the paint was optimized so that an efficient antifouling effect is reached with the incorporation of a small amount of loaded HNTs. The use of 10 wt% of loaded HNTs in paint drastically enhanced material antifouling properties by preventing the attachment of Vibrio natriegens marine bacteria, which promises wide applications for the protection of ships’ hulls.