Semiconductor Physics, Quantum Electronics & Optoelectronics, 22 (3), P. 285-292 (2019).
Dynamics of the conductance temperature dependence for composite based on linear polyethylene with impurity of soot and calcite
1Institute of Physics, NAS of Ukraine
46, prospect Nauky, 03680 Kyiv, Ukraine
Abstract. Within the temperature 293 to 425 K and frequency 10–3 to 106 Hz ranges by using the direct and alternating currents, the dynamics of electrical conductance σ of linear polyethylene with the impurity of 20 wt.% soot and 20 wt.% CaCO3 (calcite) has been investigated. It has been shown that for the solid state of polyethylene (below 380 K), the dependence of electrical conductance on the temperature T on both the direct (σDC) and alternating (σAC) currents can be described by the power dependence on T/(T – T0)
(where T0 is the temperature of the phase transition for polyethylene). It has been shown that when being repeatedly measured, the σDC and σAC values increase, and the power indexes of temperature dependence decrease. The measured values are stable after the fourth measurement. The greatest changes in the conductance, depending on the first and second measurements (almost three orders of magnitude), were observed at a temperature close to T0. It has been assumed that the dynamics of electrical conductance, depending on the number of measurements, is caused by the influence of the electric field on the ordering of impurity in polymer. It has been shown that for T 380 K, the typical for liquids Arrhenius dependence of σDC and σAC on temperature is observed. It has been found that at
the first measurement, the temperature dependence of σDC and σAC can be described
by two activation energies, while for a stable state (starting from the fourth measurement) –
by one activation energy (within the measurement error of the same for σDC and σAC and equal to 1 eV).
Keywords: electrical conductance, temperature dependence, linear polyethylene, calcite, carbon soot. This work is licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License.
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