Sunflower oil-based thermosets: Sustainable polymers via Passerini reaction
A research team led by Prof. Michael A. R. Meier of the Karlsruhe Institute of Technology has developed new ways of increasing the efficiency of coatings for the automotive industry. The results could revolutionise the development of more sustainable and longer-lasting vehicle coatings.
A recent study by the Karlsruher Institute of Technology published explores the use of sunflower oil-based tricarboxylic acids to synthesise renewable thermosets. The authors utilised a newly developed route to synthesise these acids from high oleic sunflower oil, followed by cross-linking via the Passerini three-component reaction. The researchers successfully synthesised ten different polymers by varying diisocyanide and monoaldehyde components. These polymers were characterised using various analytical techniques, including infrared spectroscopy, swelling tests, thermogravimetric analysis, and differential scanning calorimetry.
The study found that all the polymers exhibited fast curing at room temperature, making them suitable for adhesive applications. Furthermore, one polymer was chemically reused through transesterification with methanol, demonstrating its potential for circularity. The reuse process recovered azelaic acid dimethyl ester, a key compound in polyamide synthesis, with a 75% yield. The researchers also repolymerised a recovered compound into a polyurethane, highlighting the possibility of a second life cycle for these bio-based materials.
Event Tip: Bio-based Coatings
In the EC Short Course “Bio-based Coatings” on March 17, 2025 (online, 15:00 – 17:00 CET), you will learn about plant-based raw materials in coatings, their production, and the challenges of replacing fossil-based materials. The course provides insights into sustainable alternatives and their impact on the industry
Application potential and sustainability benefits
The research also highlights the practical implications of these renewable polymers in the context of sustainable material development. The ability to recycle and reuse components within the polymers showcases the potential for bio-based thermosets in a circular economy. Given their fast curing times and adhesive properties, these materials could find applications in various industries, including coatings and adhesives.
The development of sustainable thermosets derived from sunflower oil is a promising step towards reducing reliance on petrochemical resources, offering environmentally friendly alternatives in the coatings and polymer industries.
Source: Polymer Chemistry 2025, Volume 7
