Activation behavior and dielectric relaxation in polyvinyl alcohol and multiwall carbon nanotube composite films

The dc and ac electrical transport property of Polyvinyl Alcohol-Multiwall Carbon Nanotubes (PVA-MWNT) composites has been investigated within a temperature range 77≤T≤300K and in the frequency range 20Hz–1MHz. The temperature variation of dc conductivity gives the presence of two different activation energies. The dielectric properties of the samples have been explained in terms of electric modulus vector.The dielectric relaxation has been explained in terms of interfacial polarization occurring in between the insulating PVA matrix and MWNT conductive filler. The variation of the relaxation time with temperature also indicates the presence of two different activation energies.

► FESEM micrograph the rod like morphology where MWNTs are coated by PVA.
► Temperature variation of dc conductivity gives the presence of two activation ranges.
► The dielectric relaxation has been explained in terms of interfacial polarization.
► Two activation energies have also been observed in the study of relaxation time.