Summary
Epoxy is one of the most widely used insulating materials in electrical equipment due to its excellent electrical, mechanical properties and chemical stability. In recent years, researches on epoxy nanocomposites have shown that the nano-filler in epoxy can improve electrical, thermal and mechanical properties. In this paper, the effect of TiO2 nano-filler concentration on complex permittivity, conductivity and glass transition temperature of the nanocomposites were examined. The present results show that the glass transition temperature increased and relative permittivity decreased at room temperature. At relative high temperature (140 ºC and 200 ºC) above glass transition temperature the relative permittivity increase rapidly with a decrease in frequency, especially at frequency below 100 Hz which is due to the interfacial polarization and space charge polarization at the interface of epoxy/nano-filler. It was also found that the enhancement of dielectric loss factor due to abundance of mobile charge carriers is suppressed by nano-filler loading and this was also presented by the results of the conductivity at 0.1 Hz at temperature above the glass transition temperature. The relaxation time became longer and the activation energy of the relaxation decreased firstly and then increased by the titanium dioxide nano-filler loading at temperature above the glass transition temperature. These results suggest that molecular motion and carrier transport are suppressed in nanocomposites, which indicates a strong interaction between the epoxy and the nano-filler.
Additional informations
| Publication type | ISH Collection |
|---|---|
| Reference | ISH2015_197 |
| Publication year | 2015 |
| Publisher | ISH |
| File size | 718 KB |
| Price for non member | Free |
| Price for member | Free |
Authors
Meghnefi Fethi, Krbal Michal, Orsagova Jaroslava, Kim Yong Joo, Kim Hee Dong, Thejane Keneilwe Venetia, Van Coller John , Beutel Andreas
