Structure and properties of electrically conducting composites consisting of alternating layers of pure polypropylene and polypropylene with a carbon black filler

摘要

Electrically conducting composites consisting of alternating polypropylene (PP) and carbon black (CB)-filled-polypropylene (PPCB) layers were prepared by multilayered coextrusion. The co-continuous structure with selective location of CB in PPCB layers was controllable by changing the number of multiplying elements, and decreased the percolation threshold and electrical resistivity of multilayered composites because of the double percolation effect. This double percolation could be achieved in a single polymer matrix using multilayered coextrusion, whereas it can only be produced in two different polymeric matrices by conventional approaches. The electrical resistivity, positive temperature coefficient effect of multilayered composites depended strongly on their number of layers.