Comparison of polyelectrolyte and sodium dodecyl benzene sulfonate as dispersants for multiwalled carbon nanotubes on cotton fabrics for electromagnetic interference shielding

Abstract

Cotton fabrics with multiwalled carbon nanotubes (MWCNTs) dispersed by Nafion, a polyelectrolyte, and sodium dodecyl benzene sulfonate (SDBS), a surfactant, were prepared for electromagnetic interference (EMI) shielding. The fabrics were characterized by scanning electron microscopy and vector network analysis. The fabrics with the Nafion–MWCNT coating possessed a better shielding efficiency (SE) than those with the SDBS–MWCNT coating because of a more uniform dispersion of MWCNTs, which improved the electrical conductivity and EMI shielding properties. The maximum SE value of the fabric reached 11.48 dB, and the specific SE was 39.6 dB cm3/g. The reflectivity and absorptivity were calculated separately to determine the main mechanism of EMI shielding. The absorptivity was 68.6% at 12 GHz for the Nafion–MWCNT‐coated fabric; this showed that the dominant mechanism of EMI shielding for the treated fabrics was absorption. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40588.

Facile Preparation of Continuous and Porous Polyimide Aerogel Fibers for Multifunctional Applications

“…Furthermore, the EMI shielding performance is increased to 44 and 54 dB by laminating two (0.73 mm) and three (1.2 mm) pieces of the fabric at a fixed frequency of 10 GHz. These SE values are superior to many of the reported EMI shielding fabrics, including PANI/PPy/PAN fabric (∼25 dB, 30−1500 MHz), 51 PPy/GO wool fabric (22.2 dB, Xband), 52 CB/PVA/NRL cotton fabric (37.7 dB, X-band), 53 MWCNT/cotton fabric (11.5 dB, X-band), 54 etc. To explore the EMI shielding mechanism of the AgNP-deposited PAF fabric, the total EMI shielding effectiveness (SE T ), microwave absorption (SE A ), and microwave reflection (SE R ) at a frequency of 10 GHz were investigated.…”

1CoFe/C Nanosheets on Hollow Carbon Fibers as Composite Fabrics for Electromagnetic Interference Shielding

“…Before EMW enters into the shielding composite, a large part of the EMW was reflected from the first interface, and the EMW entering into the EMI shielding material was mainly absorbed . Comprehensively considering SE and SSE, as shown in Figure e,f, and Table S3, the shielding performance of our EMI shielding material is equivalent to that of the recently published shielding material. − ,,,,,− However, the density of CoFe/C/HCF-800 is only 0.28 g/cm 3 , and its EMI shielding performance and its SSE can reach 30.7 dB and 109.64 dB·cm 3 /g, respectively.…”

Near-Instantaneously Self-Healing Coating toward Stable and Durable Electromagnetic Interference Shielding

“…A vector network analyzer (VNA, Agilent N5424A) was used to measure the SE in the frequency range of 8.2–12.4 GHz (X-band), which is widely used in many applications, such as Doppler radar, TV signal transmissions, mobile phone relay systems, and other communication technologies [ 37 ]. The sample size is fixed at 22.86 × 10.86 mm 2 .…”