Electrical behavior of PET-matrix composites

The electrical properties of composites prepared by injection or compression molding of poly(ethylene terephthalate) (PET) with different amounts of filters were studied. The resistivity of composites with low filler concentrations was found to depend on the microstructure imposed by the preparation process. The resistivity of filler materials dominates at higher concentrations. Interfacial polarization and/or hopping conductivity in mica due to impurities may contribute to the conductivity of PET/mica composites. The dielectric response in the 10/sup 3/-10/sup 7/ Hz region was found to be qualitatively dominated by the PET matrix, exhibiting a beta -relaxation centered around 5.4*10/sup 5/ Hz. However, absolute values for in /sub 1/ and in /sub 2/ are influenced by the properties of corresponding fillers. Measurements of in (f) over a wider frequency range should help clarify the correlation of composite microstructure and dielectric response.<
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