Self-healable castor oil-based waterborne polyurethane/MXene film with outstanding electromagnetic interference shielding effectiveness and excellent shape memory performance.

Recently, the increasing demands of the portable devices and flexible electronics have caused lots of electromagnetic wave pollution. MXene, a novel two-dimensional material, was considered as a promising two-dimensional material for preparing flexible electromagnetic interference (EMI) shielding films. Herein, we firstly synthesized a series of flexible and self-healable EMI shielding waterborne polyurethane (ADWPU) films by mechanically blending with Ti3C2Tx (ADWPU-T). Interestingly, the self-assembling between ADWPU and Ti3C2Tx constructed a tunable analogical structure providing reflection-absorption-multiple reflection shielding mechanism. Furthermore, the ADWPU-T emulsions were prepared from castor oil which is a low-cost and eco-friendly biomass polyol. The chain extender 2-aminophenyl disulfide endow a reversible dynamic polymer network which leading to shape memory performance (45°C heat treatment) and self-healing ability (60°C, 5 min healed). Above all, these multifunctional flexible films also exhibited outstanding EMI shielding performance (51.37 dB) and performed less decrement after 200 times bending and 80°C aging test for five days. Therefore, this work would provide a novel promising method for preparing responsive electromagnetic interference shielding products and smart electronic devices.