Enhanced electromagnetic interference shielding effectiveness of polyaniline functionalized carbon nanotubes filled polystyrene composites

  • Parveen Saini
  • Veena Choudhary
Research Paper


Multiwall carbon nanotubes (MWCNTs)/polystyrene composites were fabricated by solution processing route using non-covalently functionalized (polyaniline coated) MWCNTs. These composites exhibit an extremely low percolation threshold (0.12 vol.% MWCNT) along with micro porosity and are found to have potential applications in the areas of electromagnetic interference (EMI) shielding and electrostatic dissipation (ESD) with an ESD time of 0.78 s and shielding effectiveness of −23.3 dB (>99 % attenuation). The EMI shielding was found to be dominated by absorption (−18.7 dB) with a nominal contribution from reflection (−4.6 dB) that can explained in terms of multiple internal reflection phenomenon driven by high conductivity and the porous structure.


Polyaniline Conducting polymers Electrical conductivity Antistatic EMI shielding effectiveness Absorption loss and reflection loss 



We wish to thank Director NPL for his keen interest in work. We are also thankful to Mr. K.N. Sood for recording SEM images.

Supplementary material

11051_2012_1415_MOESM1_ESM.doc (1.2 mb)
Supplementary material 1 (DOC 1208 kb)


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Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  1. 1.Polymeric & Soft Materials SectionCSIR-National Physical LaboratoryNew DelhiIndia
  2. 2.Centre for Polymer Science & EngineeringIndian Institute of TechnologyNew DelhiIndia

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