Electromagnetic interference shielding effectiveness of MWCNT filled poly(ether sulfone) and poly(ether imide) nanocomposites

• Published in: Polymer engineering and science Vol. 54; no. 11; pp. 2560 - 2570
• Main Authors: Mohanty, Aruna Kumar, Ghosh, Anindita, Sawai, Pravin, Pareek, Kapil, Banerjee, Susanta, Das, Amit, Pötschke, Petra, Heinrich, Gert, Voit, Brigitte
• Format: Journal Article
• Language: English
• Published: Hoboken, NJ Blackwell Publishing Ltd 01.11.2014; Wiley; Society of Plastics Engineers, Inc
• Subjects: Applied sciences; Carbon; Composites; Computer industry; Conductivity; Electric properties; Electrical conductivity; Electrical resistivity; Electromagnetic interference; Electromagnetism; Exact sciences and technology; Forms of application and semi-finished materials; Nanocomposites; Nanotubes; Noise levels; Polyetherimides; Polymer industry, paints, wood; Polymers; Resistivity; Scanning electron microscopy; Shielding; Technology of polymers; Transmission electron microscopy; United States; India; Electrical conductivity; Electrical properties; Aromatic polymer; Carbon nanotubes; Ethersulfone polymer; Electromagnetic shielding; Experimental study; Composite material; Compression molding; Multiwalled nanotube; Morphology; Concentration effect; Percolation; Nanocomposite; Etherimide polymer
• ISSN: 0032-3888; 1548-2634
• DOI: 10.1002/pen.23804

Multiwalled carbon nanotube (MWCNT) filled poly(ether sulfone) (PES) and poly(ether imide) (PEI) composites were prepared with different MWCNT weight fractions (0.5–5wt%) by a solution mixing technique. Their electrical conductivities, electromagnetic interference (EMI), shielding effectiveness (SE), return loss (RL), and absorption loss (AL) were investigated. Morphologies of the fracture surfaces of nanocomposites studied by scanning electron and transmission electron microscopy showed relatively good MWCNT dispersion and distribution. The electrical conductivity of compression molded samples measured at room temperature indicated that the electrical percolation network was achieved already at 0.5% loading. The measurements of shielding effectiveness (SE) carried out in the frequency range of 8 to 12 GHz (X‐band range) showed that SE increases with measurement frequency and with filler loading, whereby no significant differences could be observed between PES and PEI as matrices. The nanocomposites based on both matrices with 5 wt% loading of MWCNT exhibited shielding levels at 8 GHz between 42 and 45 dB in comparison with the pure polymers which showed value in the range of 1 to 2 dB. RL and AL showed significantly lower values for the composites as compared to unfilled polymers, but no systematic trends were observed on frequency. POLYM. ENG. SCI., 54:2560–2570, 2014. © 2013 Society of Plastics Engineers