Effects of the addition of multi-walled carbon nanotubes on the positive temperature coefficient characteristics of carbon-black-filled high-density polyethylene nanocomposites

This study investigates the effects of the addition of multi-walled carbon nanotubes (MWNTs) on the positive temperature coefficient (PTC) characteristics of conventional carbon black (CB)/high-density polyethylene (HDPE) composites. MWNT/CB/HDPE hybrid nanocomposites were prepared by the combined solution and melt-mixing process. The obtained results indicated that the PTC intensity and repeatability of the hybrid nanocomposites were dramatically improved by adding a small amount of MWNT and that the optimal MWNT content corresponded to the CB content. The initial resistivity of the materials decreased with increasing MWNT content, but not always in the PTC intensity. (c) 2006 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.