Container-based multifunctional self-healing polymer coatings

The main aim of this minireview is the demonstration of the recent progress achieved in the development of nanocontainer-based self-healing coatings for the protection of metal structures. This minireview covers the reports published within the last three years. Two main types of nanocontainers – polymer capsules and porous composite inorganic nanoparticles loaded with inhibitors or healing agents – are described. The release of the encapsulated active material is achieved by two main triggers: mechanical rupture of the container shell or changes of the local pH in the corroded area. Despite considerable steps made in the field of nanocontainer-based coatings in recent times, challenging problems remain with the mixing of nanocontainers with the coating polymer matrix, effective loading of nanocontainers with inhibitors or healing material and distribution of nanocontainers in the coating matrix.