Thermoconductive Ultralong Copper Nanowire-Based Aramid Nanofiber Nanopapers for Electromagnetic Interference Shielding

Abstract

Nowadays, the advancement of thermoconductive electromagnetic interference (EMI) shielding materials for the next generation of electronics is in high demand. We present, in this research, the fabrication of the highly thermoconductive nanopapers based on aramid nanofiber (ANF) and ultralong copper nanowires (ULCuNWs) with outstanding EMI shielding effectiveness (SE) and mechanical properties. A homogeneous red brick color nanopaper (thickness 40–50 μm) was fabricated by homogenizing a mixture of the ULCuNWs (10–40 wt %) in the ANF suspension, then vacuum filtration, and drying. The morphology of the nanopapers reveals that the ULCuNWs were uniformly dispersed and interweaved with ANF to form two-dimensional (2D) layers in the nanopapers. With the increase in the ULCuNWs content, the nanopaper shows outstanding mechanical properties and reaches the optimal tensile strength (σ) of 228 MPa and Young’s modulus of 6.12 GPa at the filler content of 30 wt %. Moreover, the variation of the in-plane thermal conductivity (λ//) and EMI SE of the nanopapers strongly depends on the amount of the ULCuNWs; the ULCuNWs30/ANF nanopapers obtain a notable λ// and EMI SE of around 8.25 W·m–1·K1 and 54.7 dB, respectively, with the mass content of 30 wt % at ambient conditions. The thermal treatment of the ULCuNWs30/ANF nanopapers at 180 °C increases the λ// and EMI SE by 60% and 9%, respectively. The ULCuNWs30/ANF nanopaper demonstrates an impressive heat dissipating capability. In addition, the ULCuNWs/ANF nanopapers show eminent thermal stability up to 500 °C and flame retardancy with an extremely low total heat release of 0.72 kJ·g–1. Therefore, ULCuNWs/ANF nanopapers can be considered great potential materials alternative to the current thermoconductive materials for heat dissipating applications in modern electronics.

Ultrafine aramid nanofibers prepared by high-efficiency wet ball-milling-assisted deprotonation for high-performance nanopaper

“…5e, for details see Table S4, ESI †). 2,8,18,21,22,29,[45][46][47][48][49][50] To understand the reinforcing and toughening mechanism of the ultrafine ANFs, we conducted the tensile fracture surface morphologies of different nanopapers after complete breakage. As shown in Fig.…”

Aramid Nanofiber/Polypyrrole Composite Films for Broadband EMI Shielding, Wearable Electronics, Joule Heating, and Photothermal Conversion

“…18−20 Recently, ANF as a matrix has attracted the attention of researchers due to its excellent mechanical performance and strong interfacial adhesion of many functional groups during the deprotonation process. Tran et al 21 fabricated ANF/ CuNW composites with an EMI SE of 54.7 dB in the X-band and mechanical properties of 228 MPa at a CuNW filler content of 30%. Li et al 22 exploited a multiple filtration layerby-layer process and hot pressing method to produce multilayered ANF/silver nanowire (AgNWs) films.…”

“…One-dimensional aramid nanofibers (ANFs), derived from poly-phenylene terephthamide (PPTA) fibers, have a lot of advantages, such as ultrahigh strength, high elastic modulus, excellent temperature resistance and water resistance, low density, prominent thermostability, and UV blocking. − Recently, ANF as a matrix has attracted the attention of researchers due to its excellent mechanical performance and strong interfacial adhesion of many functional groups during the deprotonation process. Tran et al fabricated ANF/CuNW composites with an EMI SE of 54.7 dB in the X-band and mechanical properties of 228 MPa at a CuNW filler content of 30%. Li et al exploited a multiple filtration layer-by-layer process and hot pressing method to produce multilayered ANF/silver nanowire (AgNWs) films.…”

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

“…Being surrounded by harmful EMWs for a long time would inevitably cause severe damage to human health, such as headaches and nausea 3 . Under such electromagnetic interference (EMI) conditions, electronic equipment's regular operation and performance would also be seriously influenced 4 . Therefore, EMI shielding materials with superior shielding efficiency (SE), as well as absorption‐dominated mechanism have been urgently required to guarantee the dependability of electronic equipment and prevent the information leakage 5,6 …”

“…3 Under such electromagnetic interference (EMI) conditions, electronic equipment's regular operation and performance would also be seriously influenced. 4 Therefore, EMI shielding materials with superior shielding efficiency (SE), as well as absorption-dominated mechanism have been urgently required to guarantee the dependability of electronic equipment and prevent the information leakage. 5,6 Unlike the highly conductive metal materials with a shielding mechanism of reflection loss, the conductive polymer composites (CPCs) performed significant advantages including lightweight, anticorrosion to chemicals, excellent processable performance, and adjustable EMI shielding performance.…”