Towards an antibacterial self-healing coating based on linseed oil/ZnO nanoparticles repair agent, encapsulated in polyurea formaldehyde microcapsules

This research aims at investigating the idea of anti-bacterial self-healing coatings based on polyurea formaldehyde microcapsules (MCs), with the repair agent being ZnO-containing linseed oil. ZnO nanoparticles were added to the repair agent with the idea of developing an antibacterial coating. The idea was to entrap some ZnO nanoparticles inside microcapsules, aiming for some local release of ZnO nanoparticles where the coating is damaged. The corrosion resistances of the coatings were studied using the Tafel polarization test. The structure of the coating samples was evaluated using a scanning electron microscope. To check the antibacterial properties of ZnO-containing self-healing samples, Escherichia coli and Staphylococcus aureus bacteria were used. Results showed that ZnO nanoparticles were distributed not only inside microcapsules but also over the walls, inferring that overall protection can also be attained in addition to local anti-bacterial performance. Results showed that the proposed multi-functional coating has promising antibacterial and self-healing responses.