High-Performance Poly(imide-imine) Vitrimers Derived from Semiaromatic Bisimide Diamines

A series of high-performance poly(imide-imine) hybrid (PIIH) vitrimers derived from five diamines containing an internal bisimide unit and alicyclic structure have been constructed. The mechanical and thermal properties have been drastically improved to 97.0 MPa for tensile strength, 2.64 GPa for tensile modulus, 306 °C for glass transition temperature, and 348 °C for onset thermo-decomposition temperature, much higher than those of many reported polyimines. Owing to the inclusion of a hydrophobic alicyclic structure, the water uptake of the resulting PIIHs significantly decreases, and their polymer network remains almost intact albeit after soaking in water for 24 h. The resultant PIIHs can be healed and exhibit ∼90% healing efficiency for tensile strength in the presence of primary amine and can be rapidly degraded in primary amine solution and acid solution containing DMF. The proposed hybridization strategy enables the development of rehealable polymers with robust and heat-resistant polymer networks, making them well-suited for potential use in some harsh environments requiring polymer rehealing and degradation.