Self-Healing Coatings Advance Corrosion Protection for Oil and Gas Infrastructure

When a tree is injured by the forces of nature, be it animal, weather, or human, it attempts to repair the damage by producing sap to seal the wound, creating a natural barrier from potential infection, wood-damaging insects, and dehydration. Much like blood in humans and other animals, the sticky fluid fills the breached area then dries or clots, sealing off the wound from the elements. The use of self-healing materials in construction dates to the Roman Empire. When building, the Romans would use a lime-based mortar found to have self-healing properties. A mix of volcanic ash, quicklime, and water would be used to bond larger rocks. Lime, interacting with other chemicals in the mix, would be replaced by crystals of calcium aluminosilicate. These crystals would grow into zones where cracks developed, resulting in a filling of the fracture. This healing agent has kept some Roman structures sound for centuries. Today, industries such as oil and gas use sealing and barrier solutions—whether on a flange connections, pipe termini, or similar interfaces—to combat leakage, corrosion, or contamination. Oilfield coatings are available in many different “flavors” with varying roles and compositions—some are simply designed to protect pipes and connections from the elements, while others offer more specialized chemistries for specific uses. For example, some excel in subsea roles, high-temperature regimes, or harsh environment locations. In OTC 35879, a team of researchers from Universiti Teknologi Petronas reviewed the potential of self-healing coating technologies. These coatings can automatically repair surface corrosion and erosion, improving durability and extending the lifespan of the coated equipment. Where cracks, scratches, and corrosion can appear over time, these unique coatings can restore protective properties without intervention. Self-healing coatings have been commercially available for many years in businesses such as concrete/cement production, but their introduction to the oil and gas space has been a tempered one, with few contractors offering these types of coatings to clients. “This review primarily emphasizes the application of self-healing coatings across various industrial sectors, including automotive and aerospace,” explained Nur Hidayah Salazi, research officer with the Institute of Sustainable Energy & Resources Research, Innovation, and Commercialization, Universiti Teknologi Petronas, and coauthor of the paper. “It lays the groundwork for investigating their potential in the oil and gas industry. At present, the implementation of self-healing coatings in oil and gas is in the preliminary stages, and there are relatively few studies and resources available. However, this area presents exciting opportunities for future research and development.” As with most metal structures, corrosion is the enemy. Over time, corrosion can eat away at structures, both jeopardizing integrity and shortening lifespans. The problem can be exacerbated by environmental conditions, chemical exposure, and everyday wear and tear. Coatings are used to seal in integrity, preserve both shape and soundness, and keep external, corrosion-causing forces at bay. The paper examines a pair of popular self-healing coating mechanisms—macrocapsule systems and vascular network systems.