A reconfiguring and self-healing thermoset epoxy/chain-extended bismaleimide resin system with thermally dynamic covalent bonds

摘要

Muti-functional shape memory materials based on epoxy resins (EP) with different concentration of chain-extended bismaleimide resins (CBMI) were fabricated. The resulting EP/CBMI polymers have high glass transition temperature (Tg: 93–125?°C), excellent thermal stability and good mechanical property. Unlike traditional shape memory polymers (SMPs), EP/CBMI SMPs are capable of shape reconfiguration and self-healing abilities. EP/CBMI polymers have high cycle-life shape memory property at high temperature, and their original shapes can be quickly recovered within 21?s by thermal activation method. Because of dynamic transesterification, EP/CBMI polymers can exhibit plasticity and reconfigure their shapes when heated to the temperature of dynamic transesterification (200?°C). For the same reason, EP/CBMI polymers also exhibit good healing behavior, and a 77.5–86.5% recovery of fracture toughness can be obtained after the fractured EP/CBMI polymers are healed at 200?°C/2?h.