Frequency‐selective electromagnetic interference shielding carbon spacer yarn fabric/polyurethane foam composites

Abstract

3D fabric‐reinforced composites with electromagnetic interference (EMI) shielding performance are in urgent demand to deal with the electromagnetic (EM) pollution. In this work, carbon spacer fabrics/polyurethane foam (CSF/PUF) composites were prepared via in situ integration of PUF with fabrics. Their EMI shielding and frequency‐selective performances were realized via designing 3D fabric. CSF/PUF possesses two types of Fabry‐Pérot cavities that generated incident EM waves' resonances according to the quarter‐wavelength theory. The average total EMI shielding effectiveness (SET) of 3CSF/PUF was 69.6 dB in the X band. The maximum EMI SET of 3CSF/PUF was up to 83.2 dB in 9.7 GHz. The peaks of EMI SE move to the high‐frequency region with the increase of carbon spacer yarns' density. Moreover, CSF acted as a reinforcement role and significantly improved the mechanical properties of PUF. The peak stress under compression, three‐point bending and low‐velocity impact increased by 4.2‐, 5.6‐, and 4.9‐folds, respectively. CSF/PUF also exhibited good thermal insulation properties, maintaining a temperature difference of at least 19.5°C across its thickness at 60°C. The as‐prepared spacing yarn carbon fabric‐reinforced composite foams may raise an interest to explore multifunctional EMI materials via fabric structure design.

Fabrication of Multiwalled Carbon Nanotubes (MWCNT) and Reduced Graphene Oxide (rGO)‐based thermoplastic polyurethane and polypyrrole nanocomposites for electromagnetic wave absorption application with a low reflection

“…So, the process of absorption, reflection, and multiple internal reflections of EMW results in EMI shielding in a material. The capacity of a shielding functionary to attenuate the intensity of an EMW is measured by SE and is measured in decibels (dB), as per Equation () 52–54 where SE Tot = total shielding effectiveness. P i and P t are the incident as well as the transmitted power of the EMW.…”

“…51 So, the process of absorption, reflection, and multiple internal reflections of EMW results in EMI shielding in a material. The capacity of a shielding functionary to attenuate the intensity of an EMW is measured by SE and is measured in decibels (dB), as per Equation ( 1) [52][53][54]…”

Recent advances in structural design of conductive polymer composites for electromagnetic interference shielding

“…The polymer foams (including polyurethane foam, melamine foam, PDMS foam, polyimide foam, and formaldehyde resin foam) were highly suitable as the framework and template for the deposition of nanofillers due to their continuous 3D skeleton and porous structure 238–242 . The porous polymers have been utilized for the large‐scale fabrication of porous conductive foams and CPCs, which possessed the advantages of high porosity, low modulus, excellent mechanical properties, durability and low price 243–245 .…”

“…The polymer foams (including polyurethane foam, melamine foam, PDMS foam, polyimide foam, and formaldehyde resin foam) were highly suitable as the framework and template for the deposition of nanofillers due to their continuous 3D skeleton and porous structure. [238][239][240][241][242] The porous polymers have been utilized for the large-scale fabrication of porous conductive foams and CPCs, which possessed the advantages of high porosity, low modulus, excellent mechanical properties, durability and low price. [243][244][245] For example, Shen et al 243 prepared the porous and compressible conductive PU/graphene (PUG) composite foam by impregnating the commercial porous PU sponge into GO solution and then chemical reduction, where a 3D conductive rGO network around the PU F I G U R E 8 (A-C) SEM images of GA, unfoamed TPU/GA and foamed TPU/GA composites; (D) EMI SEs of unfoamed TPU/GA and foamed TPU/GA composites in X-band frequency; (E) Schematic of attenuation mechanism of incident EMWs for TPU/CRGO composite foams.…”

Preferential localization of conductive filler in ethylene‐co‐methyl acrylate/thermoplastic polyolefin polymer blends to reduce percolation threshold and enhanced electromagnetic radiation shielding over K band region

“…In the technologically advanced age, the enormous utilization of contemporary electronic appliances and telecommunication systems, which operate at microwave and radio frequencies are responsible for the birth of a novel hazard known as electromagnetic interference (EMI), having detrimental effects on modern society. [1][2][3][4][5] EMI not only interferes with electronic gadgets but sometimes can be responsible for the severe catastrophe of revenue, energy as well as human life. Consequently, EMI shielding draws excellent attention in the research field and daily life to prevent the calamity of electromagnetic radiation in the microwave region.…”