Self‐healable electromagnetic interference shielding composite films with temperature and strain dual responsiveness

Abstract Responsive films have attracted much attention in recent years for their great potentials in actuators, smart devices, robots, communication and anti‐counterfeit, and so on. In this work, multifunctional films combining self‐healing, responsiveness, and electromagnetic interference (EMI) shielding ability are successfully fabricated via incorporating carbon nanotubes (CNTs) into hydroxyl terminated polybutadiene (HTPB), which is dynamically crosslinked by boric acid (BA). The HTPB‐BA substrate shows excellent self‐healing ability at room temperature, which facilitates the autonomous recovery of electric conductivity and mechanical strength of the composite films. Dual responsiveness to temperature and strain are found for these composite films that the electric resistance actively changes in responding to variation of temperature and strain. More encouragingly, the composite films have excellent EMI shielding ability that the effectiveness is beyond 28 dB, satisfying the commercial application. The EMI shielding efficiency is responsive to temperatures too. These responsive, EMI shielding, and self‐healable composite films may offer promising and broad prospects in the field of flexible electronics and protection of sensitive instruments.