Assam: IIT Guwahati innovates advanced epoxy coating for long-lasting steel protection

Guwahati: Researchers at the Indian Institute of Technology (IIT) Guwahati have developed a corrosion-resistant epoxy coating designed to protect steel structures exposed to seawater and high-salinity conditions.

The findings, co-authored by Prof. Chandan Das from the Department of Chemical Engineering and his research scholar Dr. Anil Kumar, were published in the journal Advanced Engineering Materials.

Corrosion is a natural process that gradually weakens metal surfaces and reduces the lifespan of critical structures. It poses a particular risk to offshore platforms, coastal bridges, port infrastructure, and marine pipelines.

Historically, corrosion has contributed to industrial disasters, including the 1984 Bhopal gas tragedy and the 1992 Guadalajara explosion, and also harms the environment, human health, and aquatic life.

While traditional barrier coatings help protect metal surfaces, they often develop microscopic defects over time, allowing moisture and salts to seep in and cause damage. To enhance protection, researchers worldwide have experimented with epoxy coatings strengthened with nanomaterials, which are ultra-small particles capable of improving coating durability and performance.

The IIT Guwahati team created a novel nanocomposite epoxy coating by combining reduced graphene oxide (RGO), zinc oxide (ZnO), and polyaniline (PANI)—a combination not previously explored for marine corrosion protection.

The researchers first attached zinc oxide nanorods to reduced graphene oxide and then encapsulated the structure with polyaniline. They blended this nanocomposite into an epoxy coating and tested it using multiple characterization methods.

The resulting coating demonstrated superior performance compared to standard epoxy. It formed a denser, more uniform barrier, adhered strongly to steel surfaces, and slowed the penetration of corrosive elements more effectively. These improvements make it ideal for marine infrastructure, offshore platforms, shipbuilding, coastal pipelines, and other steel structures exposed to saltwater.

Prof. Das stated, “Incorporating the RGO-ZnO-PANI nanocomposite into epoxy coatings offers a promising approach to achieving long-term corrosion resistance in harsh marine environments. Our next step is to assess the coating’s durability, real-world performance, and life-cycle impact.”