Corrosion costs the global economy billions of dollars each year due to costly maintenance programs and reduced-service lifetimes. Now, imagine a coating that when scratched or punctured through an impact event, can heal itself time and again, entirely preventing the catastrophic effects of long-term corrosion.
Carbon Nexus researchers Dr Jane Zhang and Dr Jerry Gan, led by Professor Russell Varley in collaboration with industry partner PETRONAS Research Sdn Bhd, have developed such a material.
The novel self-healing coating automatically eliminates cracks and scratches rapidly and efficiently entirely without external intervention. And this coating developed at IFM could be a game changer.
Prof. Russell Varley says despite the growing urgency to protect ageing infrastructure and other facilities in the 21st century, there are few examples of self-healing materials available commercially.
‘We believe that our technology represents a breakthrough in the development of applications for self-healing materials,’ Prof. Varley says.
‘Self-healing materials enable service life extension of structures and reduced maintenance regimes, thereby improving safety and resource utilisation.
‘Based upon the use of tough and durable polyurethane coatings, our concept has incorporated dynamic boronic ester linkages, imparting smart and efficient reversible behaviour to the coating. The healing mechanism only requires moisture from the atmosphere to effectively restore performance and protect the underlying surface from corrosion.’
An important aspect of this technology is that the healing derives entirely from the inherent structure of the coating, which means that healing can occur time and time again in the same location.
Prof. Varley says research on self-healing polymer coatings, which started in the early 2000s, has been limited due to many technical issues, such as redundancy, the complexity of fabrication, impact upon static performance and durability of the healing agent.
Lead researcher Dr Zhang says previous research has found boronic ester networks to display excellent self-healing, but their lack of long-term durability has limited their application as coatings for extreme environments.
‘Mechanical strength, adhesion, scratch resistance and weatherability are all properties that are equally critical to the long-term function of the coating, but our coating has it all, excellent long-term performance and a dormant yet efficient self-healing mechanism able to respond when required,’ Dr Zhang says.
‘Furthermore, we have shown that when subject to accelerated long-term UV and salt spray exposure, there is no surface blistering, no rusting or delamination from the carbon, a strong indication of durability and abrasion resistance in harsh conditions.’
Prof. Varley says this breakthrough coating has the potential to benefit other industries beyond energy industries.
‘Coatings are ubiquitous and developing a coating that requires less maintenance will pay for itself many times over in many applications,’ he says.
At this stage, targeted application areas include any coating that requires long-term durability where repair is costly and difficult, such as off-shore platforms, pipe and pipelines and wind turbines
‘Self-healing holds enormous promise to be part of the solution for many of the grand challenges in society, from resource efficiency to service life extension and repair of the built environment,’ Prof. Varley.