Electrical properties of carbon black filled polyethylene
Article first published online: 25 AUG 2004
Copyright © 1978 Society of Plastics Engineers, Inc.
Polymer Engineering & Science
Volume 18, Issue 8, pages 649–653, June 1978
How to Cite
Narkis, M., Ram, A. and Flashner, F. (1978), Electrical properties of carbon black filled polyethylene. Polym Eng Sci, 18: 649–653. doi: 10.1002/pen.760180808
- Issue published online: 25 AUG 2004
- Article first published online: 25 AUG 2004
Resistivity and dielectric constant of polyethylene/carbon black compounds were measured from room temperature to 140°C. Within the polyethylene melting region a PTC/NTC (positive followed by negative temperature coefficients) phenomenon is observed, whose intensity depends on the type of carbon black, its concentration and other parameters. Reproducibility of the PTC phenomenon in polyethylene compounds containing a single type of carbon black is rather low. However, by using mixtures of carbon blacks differing appreciably in their particle size, remarkable reproducibility improvements can be achieved. Several other aspects are also discussed in the present paper covering current-voltage relationships in these materials, comparison of PTC curves with DSC thermograms upon heating and cooling, and dielectric constant-temperature relations. The carbon black concentration giving the optimum PTC intensity can be predicted approximately from room temperature data.