Polymeric Composites for Electromagnetic Interference (EMI) Shielding Applications

Electronic devices and components have seen recent rapid advances. However, electromagnetic waves generated by electronic systems may interfere with the electroniccomponents. In recent years, electromagnetic interference (EMI) shielding and absorbing materials, which can effectively prevent the leakage of harmful EM wave, have attracted considerable attention with the increasing application of electronic devices such as television, computers, mobiletelephones and automobile communication apparatuses, etc., that emit electromagnetic (EM) energy resulting inelectromagnetic wave pollution. In this paper, we briefly introduce the EMI shielding and reviews the development of polymer-based composites for EMI shielding, in whichpolymers act as absorbing components or/and matrixes. Electrically conductive materials, especially Polyaniline (PANI) and Polypyrrole (PPy), are used to protect electronicequipment from EMI. A good electromagnetic shielding material should have both high electrical and high magneticconductivities in order to get best shielding effect in a wide range of frequency. The Shielding effectiveness (SE) of thecoatings increased with PANI percentage and conductivity of the coatings. The SE of EMI of MWCNT/PMMA increased with MWCNT content and the composites prepared in situhave higher SE values. Microwave transmission decreased with the increase of dopant concentration, while microwave reflection increased with the increase of dopant concentration

Keywords:

Electromagnetic Interference , EMI shielding , Composites , conducting polymer