Electrical Properties and Electromagnetic Interference Shielding Effectiveness of Interlayered Systems Composed by Carbon Nanotube Filled Carbon Nanofiber Mats and Polymer Composites

Abstract

The demand for multifunctional requirements in aerospace, military, automobile, sports, and energy applications has encouraged the investigation of new composite materials. This study focuses on the development of multiwall carbon nanotube (MWCNT) filled polypropylene composites and carbon nanofiber composite mats. The developed systems were then used to prepare interlayered composites that exhibited improved electrical conductivity and electromagnetic interference (EMI) shielding efficiency. MWCNT-carbon nanofiber composite mats were developed by centrifugally spinning mixtures of MWCNT suspended in aqueous poly(vinyl alcohol) solutions. The developed nanofibers were then dehydrated under sulfuric acid vapors and then heat treated. Interlayered samples were fabricated using a nanoreinforced polypropylene composite as a matrix and then filled with carbon fiber composite mats. The in-plane and through-plane electrical conductivity of an eight-layered flexible carbon composite (0.65 mm thick) were shown to be 6.1 and 3.0 × 10−2 S·cm−1, respectively. The EMI shielding effectiveness at 900 MHz increased from 17 dB for the one-layered composite to 52 dB for the eight-layered composite. It was found that the reflection of the electromagnetic waves was the dominating mechanism for EMI shielding in the developed materials. This study opens up new opportunities for the fabrication of novel lightweight materials that are to be used in communication systems.

Polypropylene Nanocomposite Filled with Spinel Ferrite NiFe2O4 Nanoparticles and In-Situ Thermally-Reduced Graphene Oxide for Electromagnetic Interference Shielding Application

“…Further, the SSE is not a sufficient design parameter because a higher value of SSE can be received at a high thickness, and, consequently, there is a direct increase in the weight of the shielding material. Therefore, absolute EMI shielding effectiveness (SSE divided by material thickness) is a more realistic design parameter [60]. The absolute shielding effectiveness (SSE/t) was 192.9 dB·cm 2 g −1 , 200.0 dB·cm 2 g −1 , 215.1 dB·cm 2 g −1 , and 233.86 dB·cm 2 g −1 for NiFe 2 O 4 -Polypropylene, NiFe 2 O 4 -1wt%RGO-Polypropylene, NiFe 2 O 4 -3wt% RGO-Polypropylene, and NiFe 2 O 4 -5wt% RGO-Polypropylene elastomer nanocomposites, respectively.…”

S‐parameters, electrical permittivity, and absorbing energy measurements of carbon nanotubes‐based composites in X‐band

“…In this case, the closer this value is to 0 dB (reference: air–100% transmitter), the more energy is transmitted through the material. Based on S21 values it is possible to evaluate how much energy is actually absorbed in RAM 17 …”

Properties of multifunctional composite materials based on nanomaterials: a review

“…For high strain rate polymeric composites, uniaxial compression tests are further demonstrated where there is a substantial increase in the strength and stiffness with the strain rate. 132 In addition, prior studies have been carried out under one-dimensional stress shear and uniaxial compression state. Also, the use of numerical simulations is widely observed in crashworthiness assessment and vehicle design.…”