Effect of oxidant dosage and solvent ratio on electric properties of polypyrrole

Abstract

Three groups of polypyrrole (PPy) were synthesised at different mole ratio of FeCl₃ to pyrrole of 0·5∶1, 0·75∶1 and 1∶1, and were marked as N-PPy, H-PPy and M-PPy respectively. The effects of oxidant dosage on morphologies, chemical structures, conductivities and especially dielectric properties were contrastively studied, and the influences of solvent ratio (volume ratio of acetonitrile to water) on permittivity and dielectric loss of PPy were also studied for. The results indicate that the variation law and mechanism of morphology of H-PPy and M-PPy are unchanged when compared with N-PPy, as we have reported before. H-PPy shows the highest conductivity and dielectric loss among the three groups of PPy, which can be attributed to the most suitable oxidation and doping degree. As to the solvent ratio effect, we find that all the dielectric parameters decrease with the increase in the volume ratio of acetonitrile to water, which is due to the solvent effect.

Keywords:

• Polypyrrole
• Oxidant dosage
• Solvent ratio
• Conductivity
• Dielectric property

Acknowledgements

This work was financially supported by the following foundations: Science and Technology Support Program Project of Sichuan Province (no. 2013GZ0049) and the Fundamental Research Funds for the Central Universities and its Continuous Project (no. SWJTU09CX051).