Self-Healing Polymeric Coatings: Beyond Scratch-Healing

Specialty polymer coatings are widely used for maintenance applications, such as for bridges, refineries, power plants, ships, industrial floors, and fuel tanks. Due to routine wear and tear, micro-damage or micro-cracks within the resin matrix can be generated, which eventually lead to macroscopic damages (e.g., rupture and delamination) and reduce the operational life of the coatings. Currently available self-healing coatings are designed to heal only surface scratches through an elastic recovery of the material via utilization of stored energy. However, these coatings are unable to self-repair mesoscopic (e.g., micro-cracks and cavitation) and macroscopic damages. This project will develop a generic technology that can repair micro-cracks through a heat-stimulated simultaneous crack closing and sealing process. The approach will be based on a polymer nanocomposite coating that has a unique morphology. Phase I will demonstrate the feasibility of the approach by comparing the self-healing efficiency to that of currently available technologies. Commercial Applications and other Benefits as described by the awardee: The proposed self-healing nancomposite coating technology has immense potential in a broad range of industrial applications, including maintenance paints, marine coatings, and other special purpose coating applications. Reduction in the frequency of the repainting job not only would be cost-effective but also would help the environment by reducing the consumption of raw materials and the emission of VOCs (because solvent-borne coatings are still the leading coating category in the U.S.)