Electromagnetic Shielding Effectiveness of Multiwalled Carbon Nanotube filled Silicone Rubber

摘要

Due to the extensive use of electromagnetic fields especially for communication, the ambient electromagnetic noise pollution are higher especially in the microwave and radio frequency regions. These intentional as well as unintentional electromagnetic fields cause interference in various electronic circuits loading to temporary upsets or even permanent damage. Various conducting materials have been used to provide good electromagnetic shielding. The use of polymeric composites, such as silicone rubber with conducting fillers, for shielding applications gives many advantages like ease of processing, high strength to weight ratio and minimal metal content. In the present work, the shielding properties of multi-walled carbon nanotube filled silicone rubber are studied. The particle size and the dispersion of fillers in the polymer was studied using a Scanning Electron microscope. The conductivity was measured using 4-probe Van der Pauw method and the shielding measurements are done as per ASTM D 4935. Adding carbon nanotubes into the polymer matrix significantly improved the conductivity and hence the shielding effectiveness.