Strong and Degradable Biobased Adhesives from Epoxidized Soybean Oil and Resveratrol

Biobased adhesives from renewable feedstocks are promising for better sustainability, but achieving both strong adhesion and degradability remains challenging. Here, we report a fully biobased adhesive based on epoxidized soybean oil, citric acid, and resveratrol. The system can be processed under multiple curing conditions, including rapid heat-gun curing and conventional oven curing, and delivers lap-shear strengths up to 21 MPa on metal substrates, outperforming many previously reported vegetable oil-based adhesives. Incorporation of resveratrol enhances adhesion and network formation due to its planar, conjugated aromaticity, avoiding the severe steric hindrance common to bulkier polyphenol systems while preserving a low-cost, bio-based composition. The adhesive also shows accelerated hydrolytic degradation under basic conditions, losing over 90% of its mass in 12 hours. These results demonstrate a scalable and sustainable adhesive platform that combines high performance and end-of-life degradability.