Nanoscale Research Letters (Jan 2010)

Enhanced Dielectric Constant for Efficient Electromagnetic Shielding Based on Carbon-Nanotube-Added Styrene Acrylic Emulsion Based Composite

  • Chen Changxin,
  • Zhang Song,
  • Ni Yuwei,
  • Cai Seng,
  • Huang Jie,
  • Li Yong,
  • Li Jiang-Tao

Journal volume & issue
Vol. 5, no. 7
pp. 1170 – 1176

Abstract

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Abstract An efficient electromagnetic shielding composite based on multiwalled carbon nanotubes (MWCNTs)-filled styrene acrylic emulsion-based polymer has been prepared in a water-based system. The MWCNTs were demonstrated to have an effect on the dielectric constants, which effectively enhance electromagnetic shielding efficiency (SE) of the composites. A low conductivity threshold of 0.23 wt% can be obtained. An EMI SE of ~28 dB was achieved for 20 wt% MWCNTs. The AC conductivity (σ ac) of the composites, deduced from imaginary permittivity, was used to estimate the SE of the composites in X band (8.2–12.4 GHz), showing a good agreement with the measured results.

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