Researchers at the University of Queensland’s Australian Institute for Bioengineering and Nanotechnology (AIBN) have developed a self-repairing coating that could extend the service life of steel components and reduce the need for repeated corrosion protection.
The technology uses microscopic containers embedded in a water-based polyurethane coating to release the corrosion inhibitor benzotriazole when changes in acidity indicate potential damage. The released molecules help protect the coating where scratches and cracks develop.
Electrochemical tests indicated that the coating could restrict corrosion to 37 nanometres per year, compared with 25,000 nanometres per year for many existing high-performance coatings. This represents a corrosion rate approximately 676 times lower under the reported test conditions, although the result does not establish how much longer the coating will last in service.
Dr Asep Nugraha, a nanoarchitect at AIBN, said: “Each tiny particle is basically a nanocontainer that releases repair molecules only when the conditions demand it.”
The technology could have applications in infrastructure, oil and gas, water treatment and other industries where corrosion contributes to asset deterioration and maintenance costs. Extending the time between coating applications could be particularly useful for structures that are costly or difficult to access.
The research team is preparing for pilot-scale testing, with a commercial product targeted within five years. The findings were published in Small Science.
