Recyclable Soybean Oil-Based Adhesive with Self-Healing and Reprocessing Capabilities: A Sustainable Approach

Thermosetting adhesives are commonly utilized in various applications. However, their covalent cross-linked network structure prevents them from being reassembled, necessitating higher machining precision. Moreover, the primary raw materials used in adhesive preparation are derived from non-renewable petroleum resources, which further constrains adhesive development. This study presents a novel recyclable adhesive based on epoxidized soybean oil (SBO) incorporating dynamic boronic esters, offering self-healing and reprocessing capabilities for sustainable applications. The successful synthesis of epoxidized soybean oil and boronic esters was confirmed through analysis of 1H NMR spectra and differential scanning calorimetry results. Swelling tests and tensile curves demonstrated the presence of covalent cross-linked networks. The self-healing and reprocessing experiments indicated that the cross-linked network topology could be reassembled under mild conditions. This approach provides a sustainable alternative to traditional thermosetting adhesives, addressing concerns related to reprocessability and resource depletion.