The influence of crystalline and aggregate structure on PTC characteristic of conductive polyethylene carbon black composite

摘要

The relationship between conductivity and morphological structure of a polyethylene/carbon black composite (PE/CB) was investigated by DSC, WAXD and SAXS, and a new interpretation of the PTC (positive temperature coefficient) effect has been proposed. The PTC intensity enhanced:with increased crystallinity for the PE/CB system; a substantial PTC effect was not discovered in an amorphous polymer/CB system. The behaviour of melting, crystallization and aggregate "large size" properties of the polymer matrix were modified by annealing, which in turn made the PTC intensity increase. It is pointed out that not only crystallinity, but also long spacing and lamellar size, also affect the PTC performances. (C) 1998 Elsevier Science Ltd. All rights reserved. [References: 20]