What Does Microencapsulation Mean?
Microencapsulation is a process that makes microcapsules of solids, liquids or gases on a microscopic level. This process conserves the properties of the encapsulated material, allowing them to be released when they are needed. For coatings, microencapsulation technology is used to immobilize (lock-in) certain active coating agents (e.g., corrosion inhibitors) until a specific event triggers their release.
Corrosionpedia Explains Microencapsulation
The study of microencapsulation is of great interest for self-healing metal coatings. In this case, active agents in the coating are encapsulated to control their release. When an external condition, such as a scratch or excessive stress occurs, the microcapsules rupture or break, releasing the agents to heal the damaged areas of the coating.
For example, low-viscosity oil films can be encapsulated on metallic surfaces to prevent corrosion. When the coating is scratched, the oil flows out rapidly from the capsule to fill the exposed area. This feature helps to reconnect the coating particle network, thus maintaining barrier protection.