Chapter 17 - Multifunctional smart layers with self-cleaning, self-healing, and slow-release activities

Abstract

The most effective method to control corrosion of metallic structures is the use of organic coatings. Their effectiveness is significantly enhanced by the presence of special additives in the matrix, which enhances the service life of metallic structures. They are chemicals either dispersed in the coatings (in this case a continuous leaching increases the effectiveness), or micro/nanocapsulated when the so-called self-healing process provides the active protection. In this case the self-healing is activated by mechanical, chemical, and physical impacts. The importance of the shell and core materials as well as the preparation techniques are discussed and the increased effectiveness of coatings with micro/nanocapsules is demonstrated by numerous examples taken from diverse industrial fields. Another important application field of multifunctional smart coatings is where they show self-cleaning activity, in most cases in combination with other characteristics. The multilevel self-healing and self-cleaning approaches can combine a number of prevention and restoration mechanisms. The application fields of smart coatings as well as the number of scientific publications increases day by day, but there are problems to be solved that need effort, not only from scientists, but also from industrial partners, to improve the application of nanoreservoirs.