Electrical Conductivity of Polypyrrole–Polymethylmethacrylate Composites Determined by Impedance Spectroscopy

ABSTRACT

Thermal properties of polypyrrole–polymethylmethacrylate (PPy–PMMA) composites are analyzed by differential scanning calorimetry (DSC). A decrease in the glass transition temperature Tg with the PPy concentration content reveals the increase of segmental motion. The ac conductivity of these composites is studied in frequency range of 600 Hz to 1 MHz and temperature interval 23°C to 110°C. The study depending on the frequency has highlighted three domains: at low frequencies the conductivity is independent of frequency; at intermediate frequencies, the ac conductivity follows a power law in frequency; and at high frequency the ac conductivity can be explained in terms of hopping process.

KEYWORDS:

• composites
• conducting polymer
• polymethyl methacrylate polymer
• polypyrrole
• Dielectric properties
• glass transition temperature
• hopping process

ACKNOWLEDGMENT

This work was supported by the program PCSI (University Agency of Francophonie, Ref.: 6301PS445) and the Integrated Action Programme Morocco-Tunisia (04/TM/38). The authors acknowledge the assistance of Prof. L. H. DAO (INRS, Varennes, Canada), for the opportunity to carry out the AC and DSC measurements in her laboratory.