Lightweight and tough multilayered composite based on poly(aryl ether nitrile)/carbon fiber cloth for electromagnetic interference shielding

Abstract

Electromagnetic interference (EMI) shielding materials are of vital importance in solving increasingly serious electromagnetic pollution. Currently, metal-based EMI shielding materials (ESMs) are ubiquitously used, however, their drawbacks of high density, low corrosion resistance, and poor flexibility restrict their application scenarios. By contrast, polymer-based composite materials have superior properties such as light weight, great shock absorption performance, and high corrosion resistance, which makes them promising electromagnetic interference shielding materials. In this work, an asymmetric network of the impedance matching layer and conductive shielding layer is constructed by coupling carbon fiber cloth (CFC) with magnetic porous poly(aryl ether nitrile) (PEN) polymer composite. Scanning electron microscopy confirms the alternating layered structure of the composites and the porous structure of the polymer layer. The unique designed composites achieve the highest EMI total shielding effectiveness (SET) of 37.76 dB and absorption shielding effectiveness (SEA) of 35.33 dB, which represents the successful preparation of a type of EMI material following an absorption-dominated mechanism. The CFC-3/PEN-Fe3O4 @PEI-25 demonstrates a satisfying EMI-SE/density/thickness (SSE/t) value of 543 dB·cm2·g−1, higher than most porous polymer-based EMI composites currently. In addition, the mechanical strength of composites is enhanced due to the unique alternating multilayered structure, with the highest tensile strength of 39.03 MPa, which is much higher than the obtained porous PEN membranes via the non-solvent induced phase separation (NIPs) method. This work proposes a novel approach to the construction of lightweight and resistant to secondary contamination ESMs with high performance, exerting enormous potential for wide application.