Polypyrrole and silver particles coated poly(ethylene terephthalate) nonwoven composite for electromagnetic interference shielding

A conductive polypyrrole/silver/poly(ethylene terephthalate) composite was prepared by the polymerization of pyrrole with AgNO3 oxidant in the presence of poly(ethylene terephthalate) nonwoven. The effect of AgNO3/pyrrole mol ratio and concentrations of the reactants was investigated on the polypyrrole/silver content and surface resistivity of the composite. The deposition of shiny metallic Ag particles was observed on the composite during the polymerization of pyrrole. The weight fraction of the Ag particles in the polypyrrole/silver contents of the composite was determined by thermogravimetric analysis. It was observed from scanning electron micrographs that the morphology of the polypyrrole/silver particles changed with the increase in the polypyrrole/silver contents of the composite. The electromagnetic shielding effectiveness as well as the absorption loss, reflection loss with the values of absorbance and reflectance, showing their contributions to the electromagnetic shielding effectiveness value of the composite were determined within the frequency range of 15-3000 MHz. An absorption dominant shielding was obtained with the value of 13-15.5 desibel for double coated composite.