No abstract

In situ polymerization of pyrrole was carried out in the presence of fly ash (FA) to synthesize polypyrrole-fly ash composites (PPy/FA) by chemical oxidation method. The PPy/FA composites have been synthesized with various compositions (10, 20, 30, 40 and 50 wt%) of fly ash in pyrrole. The surface morphology of these composites was studied with scanning electron micrograph (SEM). The polypyrrole-fly ash composites were also characterized by employing X-ray diffractometry (XRD) and infrared spectroscopy (IR). The a.c. conductivity behaviour has been investigated in the frequency range 10 2-10 6 Hz. The d.c. conductivity was studied in the temperature range from 40-200°C. The dimensions of fly ash in the matrix have a greater influence on the observed conductivity values. The results obtained for these composites are of greater scientific and technological interest.

Please cite this article in press as: H.C. Madhusudhana, et al., Effect of fuels on conductivity, dielectric and humidity sensing properties of ZrO 2 nanocrystals prepared by low temperature solution combustion method, J. Asian Ceram. Soc. (2016), http://dx.

Polypyrrole and polypyrrole/copper zinc iron oxide (copper zinc ferrite) nanocomposites were synthesized by in-situ polymerization using Ammonium Persulphate as oxidising agent. The nanocomposites were synthesized by mixing polypyrrole and copper zinc iron oxide in different weight percentages. The formation of nanocomposites and changes in the structural properties were investigated by characterizing the samples using XRD, FTIR, SEM and EDX analysis. The size of the particle was analysed by XRD using Scherrer equation and found to be in 20 nm range. DC conductivity was measured in the temperature range 300 K-473 K. The DC conductivity was found to be constant for the temperature range from 300 K-433 K. But the conductivity showed an exponential increase for the temperature 433 K-473 K, and it obeys Arrhenius relation. Activation energies were evaluated from Arrhenius plots for all compositions. Results show that incorporation of additive material significantly reduces the activation energy for the DC conductivity of the composites, and the decrease in the activation energy is also dependent on the amount of the nanoparticles in the composites. As the polymers are used in the various manufacturing products, this study indicates the possibility of using such polymers in the form of composites as superior insulating material in the fields of electrical or electronic insulation and allied areas.

ABSTRACT:The in situ polymerization of pyrrole was carried out in the presence of g-Fe 2 O 3 to synthesize polypyrrole/gFe 2 O 3 composites by a chemical oxidation method. The polypyrrole/g-Fe 2 O 3 composites were synthesized with various compositions, including 10, 20, 30, 40, and 50 wt % g-Fe 2 O 3 in pyrrole. The polypyrrole/g-Fe 2 O 3 composites were characterized with X-ray diffractometry and infrared spectroscopy. The surface morphology of these composites was studied with scanning electron microscopy. The direct-current conductivity was studied from 40 to 2008C. The dimensions of the g-Fe 2 O 3 particles in the matrix had a greater influence on the conductivity values.