Electrical and thermal properties of composites based on thermoplastic polymer and low melting metal alloy
Monika Trojanowska-Tomczak, Ryszard Steller, Patrycja Szymczyk
Quarterly No. 1, 2013 pages 19-23
DOI:
keywords: polymer matrix composites, low melting alloy, electrical resistivity, thermal conductivity
abstract The paper concerns composite materials based on a thermoplastic polymer and low melting metal alloy. Composites with various alloy content were prepared by the sintering of PMMA or PVC powder to obtain a matrix with open pores. Then, liquid Wood’s alloy was intruded into the matrix using a pressure autoclave. The obtained systems consist of co-continuous, interlaced 3D networks. The microstructure, electrical and thermal properties have been investigated. SEM micrographs revealed good dispersion of the filler in the matrices. The metal alloy inclusions have irregular shapes and different sizes from a few µm up to 100 µm. The results of the resistivity measurements showed that both composites conduct electrical current well. The resistivity of the samples varies from 4.2•10-4to 1.5•10-5 Ω•m and the type of matrix does not have an influence. In contrast to electrical conductivity, the concentration dependence of thermal conductivity did not show percolation beha¬viour. The thermal conductivity of the composites increased but only slightly and its value is still closer to the polymers than to the metals. A slight reduction in the Vicat softening point of the composites was observed. It is due to the low melting temperature of the alloy, i.e. 70°C.