Recyclable flexible materials with MOF-derived nanospheres for electromagnetic wave absorption

Abstract

Self−healing and recyclable characteristics were beneficial for wave−absorbing materials to extend the service life, reduce the cost, stability and electromagnetic pollution in the practical application. The flexible composites with recyclable and electromagnetic wave (EMW) absorption were fabricated by employing MOF derived carbon nanoparticles (ZnCoNC) and polymers with dynamic boron ester bonds. The benzene structure of eugenol derived polybenzoxazine structure can stick on the surface of the MOF−derived nanoparticles by π−π interaction, which benefits the recyclable and mechanical properties. With the synergistic effect of dynamic boron ester bond and π−π interaction, the tensile strength of composites with 15 wt% ZnCoNC reached 7.88 MPa after 3 times recycling, it remained 88 % compared to origin composites. The minimum RL obtained is −36.6 dB at a thickness of 2 mm, it can approximately maintain the same effect in EMW absorption performance after recycling. This work was expected to broaden the EMW absorption application field and extend the service life of materials.