Effect of carbon black on the thermoelectrical properties of poly(ethylene-oxide) composites

Abstract

The AC electrical conduction and thermal conductivity of casted thin films of poly (ethylene oxide)/carbon black composites were investigated as a function of applied frequency in the range from 100 Hz to 5 MHz, temperature and carbon black concentrations 0, 1, 2, 4, 6, 8 and 10% by weight. The average films thickness was about 90 µm. The AC conductivity and dielectric properties were determined from impedance measurements. The study showed that the thermoelectrical properties are affected by adding carbon black filler into the poly (ethylene oxide) polymer matrix. The study observed that the dielectric constant and dielectric loss decrease with frequency, and increase with temperature, and carbon content. The AC-conductivity increases with increasing frequency, temperature and carbon black content. The observed percolation threshold of the AC-conductivity occurs at about 2 wt% carbon black concentration. The thermal conductivity of the prepared films was studied as a function of temperature and CB concentration. It was found that the thermal conductivity is enhanced by addition of the carbon black content and increasing temperature. In case of raising the temperature, the phonons are activated and electrons hopping to higher energy states, thus enhancement in the thermal conductivity is produced.

AC-impedance and dielectric properties of hybrid polymer composites

“…Additionally, CB is added to reduce the tunneling distance and increase the number of tunneling contacts, which have to be overcome by charge carriers, determining the overall conductivity. [17][18][19][20][21] CB was used as a shielding material of high-voltage cables and in numerous industrial and electronic applications as: electrical conduction, electrodes, electromagnetic reflection, heating, thermal conduction, thermoelectricity, sensing, electrical switching and electronic devices. For a required EMI shielding composite material, the filler that is effective at a low concentration is desirable because the strength and ductility of a composite tend to decrease with increasing filler content when the fillermatrix bonding is poor.…”

Polyethylene Oxide/Barium Titanate Composites: Optical, Electrical and Thermal Properties

“…Composites with the following BaTiO3 concentrations (0, 2, 4, 7, 10, and 12 wt. %) were prepared by casting method [14]. The sample sheet thickness is 0.2 m.…”

“…The Hewlett Packard (HP) 4192A impedance analyzer was used to measure the impedance and phase angle. The determined ac electrical quantities in the present paper were calculated from equations and models reported in [14].…”

“…Thermal conductivities of the tested composites were measured after heating specimens of double discs placed in the sample holder. The procedure and the determined thermal quantities were reported in [14].…”

The tunable permittivity of multi-walled carbon nanotubes/silver nanoparticles reinforced polyvinyl alcohol (PVA) nanocomposites at low frequency

“…The nanocomposite films were placed between two metal disk electrodes of 25 mm diameter and the electrical measurements were taken out at 25±1°C. The frequency dependence of dielectric properties and ac conductivity of the nanocomposites can be calculated from real, Z′ and imaginary, Z″ components of the complex impedance Z as shown in the following relations [25]:…”