Effective conductivity in association with model structure and spatial inhomogeneity of polymer/carbon black composites

TL;DR

This paper investigates how the microstructure and spatial distribution of carbon black in polymer composites influence their effective electrical conductivity, revealing that increased inhomogeneity reduces conductivity.

Contribution

It introduces a model linking composite structure and inhomogeneity to effective conductivity, supported by TEM observations and inhomogeneity measures.

Findings

Higher inhomogeneity correlates with lower conductivity.

Structures are intermediate between Maxwell-Garnett and Bruggeman models.

Effective conductivity varies with carbon black distribution.

Abstract

The relationship between effective conductivity and cell structure of polyethylene/carbon composites as well as between effective conductivity and spatial distribution of carbon black are discussed. Following Yoshida's model both structures can, in a way, be said to be intermediate between the well known Maxwell-Garnett (MG) and Bruggeman (BR) limiting structures. Using TEM photographs on composites with various carbon blacks we have observed that the larger is Garncarek's inhomogeneity measure H of two-dimensional (2D) representative distribution of the carbon black, the smaller is the effective conductivity of the composite.