Preparation, characterization, and electrical conductivity of polypyrrole composite films

• Published in: Polymer testing 2004-05, Vol.23 (3), p.361-365
• Main Authors: Migahed, M.D., Fahmy, T., Ishra, M., Barakat, A.
• Format: Article
• Language: English
• Subjects: Applied sciences; Conducting composite; Electrical conductivity; Ethylene-vinyl alcohol copolymer; Exact sciences and technology; Organic polymers; Physicochemistry of polymers; Polymer industry, paints, wood; Polymers with particular properties; Polypyrrole; Preparation, kinetics, thermodynamics, mechanism and catalysts; Technology of polymers
• ISSN: 0142-9418; 1873-2348
• DOI: 10.1016/S0142-9418(03)00101-6

Conducting composites were synthesized by oxidation polymerization of pyrrole interpenetrated in ethylene-vinylalcohol copolymer. The oxidant used was iron (III) chloride. The conductivity of composite films reaches up to 1 S/cm and can be controlled by varying the polypyrrole (PPy) amount in the composite. The activation energy, E a, of the conductivity was evaluated using the Arrhenius relationship in the low temperature region. Values of E a revealed that the activation energy decreases as the PPy content increases, suggesting the formation of more polarons. The conductivity was analyzed by the variable range hopping (VRH) model and the best results have been achieved for a one-dimensional model for charge transport in the present conducting composites. The electrically conducting polymer composite films have been characterized by scanning electron microscopy, ultraviolet/visible and infrared spectroscopy and wide angle X-ray diffraction spectroscopy. The morphology changes of the composite films could be attributed to the synthesis conditions.