Physical Properties of (TiC/Polypropylene) Conductive Composites in Relation to Their Particle-filled Structures

Abstract

Titanium carbide (TiC) ⁄ acid-modified polypropylene (m-PP) composite is one of the candidate as the PTC resistor stable in relatively high temperatures, which is utilized for a self-recoverable element protecting from over currents in many kinds of electrical circuits. In the present study, the m-PP-based composites containing various volume fraction (φ2) of TiC have been prepared; then, their viscoelastic characteristics were investigated in comparison with their electric conductivity as a function of temperature. Melting behaviors of the samples were also examined and discussed in terms of their morphological features. Alternatively, the changes in the storage moduli at room temperature with various φ2 values of the samples could be expressed by a modified Kerner equation with the maximum φ2 value of 0.69. When the value of φ2 exceeded up to be 0.36, the resistivities of the sample decreased steeply with increasing φ2 values. The filling structure of TiC⁄m-PP Composites is expected to be in random packing systems.