Fully Biobased Vitrimers from Glycyrrhizic Acid and Soybean Oil for Self-Healing, Shape Memory, Weldable, and Recyclable Materials

TLDR

Vitrimers are covalent polymer networks that can change their topology through thermally activated bond exchange reactions. In this work, fully biobased and recyclable vitrimers were developed from epoxidized soybean oil and natural glycyrrhizic acid without additional chemical modification, thereby avoiding nonrenewable petroleum resources and addressing disposal issues. The ESO/GL vitrimers exhibit excellent thermal stability, mechanical strength, and shape‑memory behavior, and can be welded, repaired, recycled, and chemically degraded by ethylene glycol, making them suitable as repairable and recyclable adhesives.

Abstract

Vitrimers are covalent polymer networks that can change their topology through thermally activated bond exchange reactions. In this work, fully biobased and recyclable vitrimers were developed from epoxidized soybean oil (ESO) and natural glycyrrhizic acid (GL) as it was without additional chemical modification, which avoided the use of nonrenewable petroleum resources and resolved the disposal problems of materials. Because of the unique rigid skeleton of GL, ESO/GL vitrimers showed good thermal stability and mechanical properties. Driven by the transesterification-induced topological network rearrangements, these ESO/GL vitrimers exhibited high performance of welding, repairing, and shape memory. They were also recyclable and chemically degradable by ethylene glycol. More importantly, these vitrimers could be used as repairable and recyclable adhesives.