A recent review shows that powder coatings made from renewable raw materials are becoming increasingly relevant. New bio-based binders such as polyester, polyamide or limonene resins enable sustainable and high-performance alternatives to conventional systems.

Powder coatings are considered to be a particularly environmentally friendly coating technology – with no VOC emissions, high material utilisation and easy recovery of the overspray. The next logical step is to use renewable raw materials in resin production. A new review article highlights current developments in the field of bio-based powder coating systems and their binder technology.

The focus is on the latest advances in the synthesis of binders from renewable sources. These include, for example, polyester resins based on plant monomers, polyamides made from natural fatty acids, and poly(limonene carbonates) obtained from citrus peel extracts. New crosslinkers such as bio-based urethane acrylates or blocked polyisocyanates are also being used.

Sustainability as a design principle in powder coating chemistry

In addition to the development of raw materials, the review also addresses the evaluation of bio-based powder coatings using common sustainability metrics such as energy efficiency, toxicity, waste prevention and recyclability. Many of the systems examined not only offer ecological advantages but also high chemical and mechanical resistance.

Due to the growing regulatory and societal pressure for sustainable solutions, research into bio-based powder coatings is clearly gaining momentum. The presented literature review therefore offers a well-founded introduction to current material concepts and shows how sustainable powder coating technologies with bio-based components can already be today.

Source: Journal of Coatings Technology and Research, Volume 21, Pages 435–444, (2024)