Water-resistant bio-based vitrimers based on dynamic imine bonds: Self-healability, remodelability and ecofriendly recyclability

Vitrimers with dynamic imine bonds generally show low mechanical properties and water resistance. Here, we report a bio-based vitrimers with dynamic imine bonds synthesized from vanillin, m-xylylenediamine and DGEBA. Among them, the imine metathesis reaction of the dynamic imine bond makes the bio-based vitrimers have rapid stress relaxation behavior, self-healing, remoldability and weldability. In addition, the materials also exhibited high mechanical properties (79.1 MPa) and excellent water insensitivity. Even after being immersed in water for 15 days, the materials still showed a tensile strength of 70.5 MPa and a Young's modulus of 2.32 GPa at a breaking elongation of 6.67%. Importantly, due to the hydrolysis of dynamic imine bonds, the materials also exhibited degradation and ecofriendly recycling capabilities under mildly acidic conditions. We envision that this vitrimers with simple process, excellent comprehensive properties and ecofriendly recyclability will make it a potential candidate for applications in sustainable structural materials.