Compensation phenomena in oil-resin mixtures: A new dielectric approach to percolative processes

• Published in: Journal of materials research Vol. 12; no. 10; pp. 2784 - 2793
• Main Authors: Pagés, O., Lamure, A., Lacabanne, C., Odlyha, M., Craig, D.
• Format: Journal Article
• Language: English
• Published: New York, USA Cambridge University Press 01-10-1997
• ISSN: 0884-2914; 2044-5326
• DOI: 10.1557/JMR.1997.0371

The methods of thermally stimulated currents (TSC) together with low frequency dielectric spectroscopy (LFDS) are combined for the first time to study percolation phenomena. These take place within oil-resin mixtures which constitute conductor/insulator-like composite systems. Each of these techniques is shown to describe selectively one of two different kinds of relaxation processes in the oil component: first, anelastic dipolar movements and second, the circulation of free charges. The separate qualitative interpretations of the combined TSC/LFDS experiments lead to convergent estimations of the percolation thresholds of the two basic materials in oil-resin mixtures. The latter appear as critical concentrations for which the dielectric relaxation processes either comply suddenly with compensation laws or pre-existing compensation phenomena change in nature.