Self-healing materials are a class of smart materials capable of autonomic repair after damage at ambient temperature without external intervention.
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Since White et al reported the first example of self-healing polymeric material capable of autonomic repair without any external intervention,
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the concept of self-healing functionality for materials has captured the imagination of academia and industry alike, and spawned the development of various chemistries and concepts for designing self-healing functionality into polymeric materials. These chemistries and concepts include autonomic options that do not require any external intervention,
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and non-autonomic options that might require heat or ultraviolet radiation, for example, to facilitate the healing response.
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Few applications have the potential to benefit more from the life extension gained by incorporating self-healing functionality into a protective coating system than offshore oil and gas structures that face harsh corrosive environments paired with costly maintenance and downtime.
Chevron, a major oil and gas asset owner, sought out a solution to one of the two most common failure mechanisms affecting protective coatings: micro-cracking and the propagation of micro-cracks that lead to water ingress to the substrate and subsequent corrosion. This was accomplished by conducting a research study in collaboration with Rust-Oleum, a manufacturer of a range of protection solutions for metal substrates, and Autonomic Materials, a supplier of microencapsulated healing agents. The primary goal of the study was to develop, validate and deploy a self-healing coating system that would extend the life of standard protective coatings, resulting in reduced costs and labor associated with coating maintenance for off-shore applications. The resulting coating systems were tested at a third-party laboratory, Charter Coating Services (2000), Ltd., in Calgary, Alberta.