A Feasibility Study of Polypyrrole/Zinc Tungstate (Ceramics) Nano Composites for D. C. Conductivity and as a Humidity Sensor.

Abstract Laboratory polymerization of pyrrole was carried by chemical oxidation method with zinc tungstate (ZnWO4) ceramic to synthesize polypyrrole/zinc tungstate nano composite in presence of ammonium persulphate [(NH4)2S2O8] as an oxidizing agent. The synthesis was made with 10 to 50 wt %. of (ZnWO4) in polypyrrole (PPy). The surface morphology of polypyrrole powder and its composites is analyzed via (SEM) Scanning Electron Microscope which revealed the embedment of (ZnWO4) particles in PPy series to form spherical character and as bunch. The Fourier Transfer Infra Red (FTIR) spectra disclose the shift of elongated frequencies on the way to the higher frequency area. The X-ray diffraction (XRD) pattern proposed semi-crystalline behavior of the composites. Thermal Gravi-metric (TG)/Differential Thermal Analysis (TG/DTA) study disclosed the polypyrrole nano composites were steadier than the pure PPy.The temperature reliant D.C. conductivity illustrated that ZnWO4 deliberation in polypyrrole was accountable for the variant of nano composites conductivity. The 40 wt. % of ZnWO4 in the composite had the superior conductivity in comparison with the rest. The humidity sensing mechanism of polypyrrole/zinc tungstate composites also were studied for the percentage relative humidity range from 30 to 95% by examining the changes in resistance.