Comparison of electrical conductivity data obtained by four-electrode and four-point probe methods for graphite-based polymer composites

• Published in: Polymer testing Vol. 26; no. 4; pp. 547 - 555
• Main Authors: Mironov, V.S., Kim, J.K., Park, M., Lim, S., Cho, W.K.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.06.2007; Elsevier
• Subjects: Applied sciences; Composites; Exact sciences and technology; Experimental measurement; Forms of application and semi-finished materials; Four-electrode method; Four-point probe method; Graphite filler; Polymer composite; Polymer industry, paints, wood; Properties and testing; Technology of polymers; Testing and control; Volume electrical conductivity; Experimental measurement; Graphite filler; Volume electrical conductivity; Four-electrode method; Polymer composite; Four-point probe method; Conducting material; Electrical conductivity; Electrical properties; Propylene polymer; Experimental study; Composite material; Vinylidene fluoride polymer; Concentration effect; Graphite; Surface properties; Olefin polymer; Measurement method
• ISSN: 0142-9418; 1873-2348
• DOI: 10.1016/j.polymertesting.2007.02.003

A comparison of the volume conductivity measured by standard four-electrode (FE) and four-point probe (FPP) methods for graphite-based powdery polypropylene (PP) and poly(vinylidene fluoride) (PVDF) composite bar specimens was made in this study. Significant difference in the conductivity data obtained by standard FE and FPP methods was found for highly conductive PP and PVDF composites which were molded from hybrid carbon/polymer powders dry-blended in a high-speed mixer and jar ball mill. However, it was found that the conductivity values were approximately equal for moderately conductive PVDF/graphite and PP/graphite composites. It was also shown that polishing the specimens to remove 100–150 μm of the surface layer and decrease surface roughness did not bring about significant changes in conductivity values. Consequently, bulk non-uniformity and inhomogeneity of graphite-based polymer material were considered to be the most probable sources of the difference in the volume conductivity values measured by the FE and FPP methods.