EMI Shielding Properties of Polymer Blend with the Inclusion of Graphene Nano Platelets

Abstract

Polymer nano composites based on poly vinyl chloride matrix were fabricated using polyaniline (PANI) and graphene nano platelets (GNP) as electrically conductive nano filler for the application of electromagnetic interference (EMI) shielding. DC conductivity was first evaluated by using cyclic voltammetry and found an increasing trend of electrical conductivity as PANI and GNP was added in PVC matrix that confirms the formation of electrically conductive network structure. Dielectric properties like dielectric constant, dielectric loss and AC conductivity were evaluated in frequency range of 100 Hz to 3 MHz that gives basic prediction for EMI shielding effectiveness. Vector Network Analyzer (VNA) was used to assess EMI shielding properties using coaxial cable method in 11GHz to 20GHz range and it was found that a maximum of 29 dB shielding was archived with the incorporation of 15 wt% of PANI in PVC. This value increased to 56 dB as 5 wt% GNP added in PVC/PANI 15 wt% blend. Interaction of matrix with filler, nature of filler and dispersion of filler in matrix are the key parameters for achieving high shielding effectiveness.

Electromagnetic interference shielding study in microwave and NIR regions by highly efficient Ag/ZnS and polyaniline-Ag/ZnS particles

“…8 The total shielding efficiency of 10 dB considered as the threshold efficiency as it can attenuate almost 90% of electromagnetic radiation and thought to be target value for use as a shielding material in commercial applications. [9][10][11] The mechanism of reflection of electromagnetic interference shielding is primarily described as the charge carriers directly contact to the EM field that reflects the radiation. 8,12,13 While the absorption of electromagnetic interference shielding is the interaction of the magnetic and electric dipoles with the waves.…”