Sustainable epoxy vitrimer materials with imine and disulfide bonds prepared from epoxidized soybean oils

Abstract

Vitrimer has become an emerging application to solve the problem of thermoset pollution and resource wastage due to its reversible cross-linked network structure that enables reuse and recycling of materials. However, it is still challenging and difficult to achieve full bioresourcing and to prepare recycling pathways with excellent mechanical strength and high efficiency. In this study, a bisphenol derivative monomer with imine bonds was first synthesized with tyramine (TA) and terephthalaldehyde (TPA), and then the monomer was used together with 4,4′-diaminodiphenyl disulfide (4-AFD) to co-cure epoxidized soybean oil (ESO) to construct an epoxy vitrimer material (ETA) with a bi-dynamic network structure. ETA-3 exhibits high 5 % thermal stability T_d5 % (319.17 °C) and energy storage modulus E (2085.35 MPa). Notably, due to the fact that it exhibits a short relaxation time (32.24 s) and low activation energy (70.07 KJ/mol), ETA can achieve the repair of scratches within 30 min at 100 °C. This test demonstrates that ETA vitrimer has a better self-repairing performance, which contributes to the continuous development of vegetable oil-based polymeric materials.