20 May 2021

Meeting the challenge of corrosion

Meeting the challenge of corrosion

Anti-corrosive paints have been used for centuries to protect metal assets from environmental conditions such as rain, moisture, and salt spray. However, rising pollution levels, use of more aggressive chemicals, and wider temperature changes are proving ever more corrosive, and today the market is demanding more from coating manufacturers.

The cost of corrosion

In 2013, NACE (now AMPP: society for protective coatings, USA) estimated the annual global cost of corrosion to be $2.5 trillion, which is 3.4% of the global GDP (2013). Applying state-of-the-art anti-corrosion paint and other preventive technologies can deliver savings between $375 and $875 billion annually.

In addition, corrosion can lead to near misses, forced shutdowns of manufacturing assets, and even environmental pollution through leaks, that can cause significant impact financially as well as to a business’ reputation. This can result in further pressure on manufacturers to deliver new solutions with increased performance characteristics. Legislations such as REACH are also an influential factor, as product safety criteria play an increasingly important role in their formulation.

Coating solutions

 Anti-corrosive paints need excellent adhesion to the substrate to form a homogeneous film that acts as a barrier against moisture and chemicals. In addition it contains  corrosion-inhibiting pigments that degrade instead of the substrate material, which is most commonly steel or concrete. As a result, the overall composition of an anti-corrosive paint consists of a binder, which is also known as a polymer or resin, plus pigments, fillers, and solvents.

Key polymers applied for anti-corrosive paints are thermosetting materials, which are usually supplied in two different packages and will be mixed just before applying the paint. After the evaporation of solvents, they crosslink and form a homogeneous film. Today, a large variety of epoxy resins and curing agents provides coating formulators flexibility to cover a wide range of application conditions and end use requirements. Crosslinking can take place from freezing to tropical temperatures, at high humidity and even submerged in water. Coatings can be made to resist the most aggressive environments. And the trend is to use less solvents or solvent-free and waterborne systems.

What's next for anti-corrosive paint?

 Thermosetting anti-corrosive paints, like 2K Epoxies, need continuous improvement from formulators and manufacturers to meet increasing market demands and performance expectations. As environmental conditions and climate change become ever more harmful to metal assets, the industry is seeking to continuously improve epoxy systems for better and more effective protection.