Structural design underpinning self-healing materials for electromagnetic interference shielding: coupling of dynamic polymer chemistry and electrical conductivity

Abstract

Electromagnetic interference (EMI) shielding materials can address the troublesome problem of electromagnetic pollution, but they are inevitably subject to damage during use, severely weakening or depriving them of their inherent shielding performance. Recently, intrinsic self-healing polymers with superior mechanical properties and recyclability have poised to become the next generation of high-performance EMI shielding materials. These materials can repeatedly restore their EMI shielding functions to achieve timely protection after external damages. In this review, we highlight the latest advancements in self-healing EMI shielding materials, divided into intrinsically conducting polymer and conductive polymer composite systems. To improve the EMI shielding performance of materials, both the conjugated structure and doping components of intrinsic conductive polymers, as well as the conductive fillers of polymer composites, can negatively impact the self-healing performance of materials. Therefore, self-healing EMI shielding materials are designed by selecting fillers that can efficiently construct conductive networks and promote the self-healing performance of materials. In particular, this review discusses existing methods of regulating the EMI shielding performance of self-healing electromagnetic shielding composites through delicately structured designs, including porous, segregated, and lamellar structures. Additionally, we further explore the future scientific and technological challenges and opportunities to develop unique self-healing materials for EMI shielding applications. It is believed that this review could encourage further creativity and innovation in this exciting and emerging branch of EMI shielding applications interfacing with polymer science and materials chemistry.