This new development will be a huge boon to the natural coatings development. This will also prove beneficial as the raw material, phytochemical, is available in abundance. Additionally, it will also help to develop more eco-friendly anti-corrosive coatings and is relatively less toxic in nature.

 

In a bid to control wear and tear of steel and impart a longer life span National Institute for Interdisciplinary Science and Technology (NIIST), Thiruvananthapuram have developed a corrosive control measure obtained from mango leaf extracts.

 

In India corrosion losses have been estimated approximately of Rs 25,000 crore per year, according to NACE, India. A team of three, 

who studied and led to the discovery of the new corrosive repellent, tested the substance on commercial steel which was subjected to extreme environmental conditions. 

 

The new corrosion repulsive was efficient in protecting substrate (steel) from corrosion.Plants have phytochemicals - a defence mechanism to protect from the external destructive agents such as pathogens and predators. The research team considered this as a hypothesis, started studying the mango plant, scientifically known as Mangifera indica.

 

These phytochemicals were extracted from dried mango leaves using ethanol. Phytochemicals also contain maximum amount of bioactive elements. Different concentrations of the pure extract were subjected to electrochemical analysis. From these readings, the sample containing 200 parts per million (ppm) of the extract showed the highest percentage of anticorrosive property.

 

Dr Nishanth K Gopalan, team leader, NIIST, explained, “The bioactive elements form an iron-polyphenol-insoluble-organometallic-compound, which is responsible for the anti-corrosive property. The isolated extract was tested for corrosion resistance by using electrochemical impedance spectroscopy. Surface analysis tests conducted using X-ray photoelectron spectroscopy revealed the role of the bioactive elements.”

 

As the pure extract cannot be sustained as a coating and making it commercially viable for use, researchers engineered a 

hybrid by loading the extract in amorphous silica, a commonly used inorganic material and commonly used in concrete for binding properties. The combination was then spread in epoxy to make it as a coating material.

 

The steel was dip-coated with the product and subjected to simulated harsh environmental conditions. The formulation demonstrated a maximum efficiency of 99 per cent, indicating anticorrosive properties of the mango leaf extract.The team plans to further experiment and put the newly developed product to test durability of the product. These tests will be based on temperature and environmental conditions, and also its efficacy on other alloys.

 

Chandrashekhar Rane, Manager-Business Development, Advance Paints Pvt Ltd, informed, “With the Indian industrial coatings segment demanding eco-friendly products, this phytochemical-based extract is a huge development in the field. Due to abundance of phytochemicals, the development has a bright future.”