Purdue research: Finding the exact combination of bio-based compounds to create sustainable adhesive system

A team of Purdue chemists led by Jonathan Wilker, professor of chemistry and materials engineering, has developed a new, completely sustainable adhesive system. The group’s findings on combining epoxidized soy oil with tannic and malic acids were published in Nature.

Article Title

Sustainably sourced components to generate high-strength adhesives

Authors

Bradley McGill, graduate research assistant, Chemistry

Clayton Westerman, graduate research assistant, Chemistry

Jonathan Wilker, professor, Chemistry and Materials Engineering

Journal

Nature, 2023 

Full Article

https://www.nature.com/articles/s41586-023-06335-7

Article Summary

Nearly all adhesives are derived from petroleum, create permanent bonds, frustrate materials separation for recycling and prevent degradation in landfills. When trying to shift from petroleum feedstocks to a sustainable materials ecosystem, available options suffer from low performance, high cost or lack of availability at the required scales. Here researchers present a sustainably sourced adhesive system, made from epoxidized soy oil, malic acid and tannic acid, with performance comparable to that of current industrial products. Joints can be cured under conditions ranging from use of a hair dryer for five minutes to an oven at 180 degrees Celsius for 24 hours. Adhesion between metal substrates up to around 18 MPa is achieved, and in the best cases, performance exceeds that of a classic epoxy, the strongest modern adhesive. All components are biomass derived, low cost and already available in large quantities. Manufacturing at scale can be a simple matter of mixing and heating, suggesting that this new adhesive may contribute toward the sustainable bonding of materials.