No 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.

Electromagnetic interference (EMI) shielding materials are effective in eliminating unwanted electromagnetic interference and reduce the potential harm to human health. Among them, the EMI shielding materials fabricated from wastes but with multiple functions are particularly attractive. However, it is always a great challenge to integrate multiple functions into one EMI shielding material, especially when using the wastes as raw materials. Here, a multifunctional EMI shielding composite was fabricated from waste rock wool, which is one of the fast-growing solid wastes in the world. The waste rock wool was converted into a valuable EMI material by simply dip-coating the rock wool into a graphene oxide aqueous dispersion and a following chemical reduction by hydrazine hydrate. The obtained rock wool/reduced graphene oxide (RW-rGO) composites showed excellent EMI shielding performance (>25 dB) and good hydrophobicity (water contact angle >130°). Moreover, the RW-rGO composites exhibit good thermal insulation and fire-retardant ability. We believe that the strategy for fabricating RW-rGO composites not only provides an effective way to solve the problem of waste rock wool pollution but also can promote the large-scale manufacturing of multifunctional EMI shielding materials.