Eletroless Silver Coated Nanocenosphere/Polymer Composite for EMI Shielding Effectiveness

Abstract

Electromagnetic interference (EMI) is an escalating concern in the modern electronic climate. As such it has become a critical area to consider when designing and packaging electronics. In this context, Electroless Silver Coated nanocenosphere (SCNC) in Poly Methyl Methacrylate (PMMA) and Acrylonitrile Butadiene Styrene (ABS) composites has been tried for its EMI shielding effectiveness. The strategy is to render the polymer conductive by dispersing SCNC in various proportions in these polymers separately and to promote wave absorption by making sheet of the polymer-based composite. In our study EDX (Energy Dispersive X-Ray) analysis confirmed the presence of Ag on the coated nano cenosphere. This was further, confirmed through Phase analysis by XRD (X-Ray Diffractometer) analysis. SEM (Scanning Electron Microscope) analysis was conducted to see the size, shape and adherence of the Ag coating on nanoenosphere particles and to observe the distribution of these particles in polymer matrix in the composite sheet. BET Surface area of electroless coated powders was quite high indicating good surface properties. The processing methods, electrical properties (surface resistivity) and electromagnetic behavior (EMI shielding effectiveness) were investigated. Shielding effectiveness (SE) values of approximately 25 dB at a frequency of 1 GHz was obtained for coatings of Electroless Silver coated nanocenospheres in ABS polymer which was further increased by adding other conductive nano fillers (Graphene and multi walled Carbon Nano tube) along with coated nanocenospheres.