Structural, electrical and magnetoresistance feature of PP+Fe3O4 + Multi-walled carbon nanotubes nano-hybrid based polymer nanocomposite

This work studied the role of the iron oxide and MWCNT in a change of the electrophysical properties of PP + Fe3O4 + MWCNT nanocomposite to evaluate the potential of these nanocomposites as magnetic field sensors and EMI materials. The morphology of the obtained nanocomposites was studied with a scanning electron microscope and investigated that the sizes of both magnetite nanoparticles and carbon nanotubes stay stable during the three-phase nanocomposite formation. In addition, the X-ray diffraction method revealed that MWCNT plays an essential role in the ordered structure-formation of a polymer nanocomposite more than iron oxide nanoparticles. Dielectric properties of the PP + Fe3O4 nanocomposite were studied. Both dielectric permeability and dielectric losses of PP+MWCNT+Fe3O4 nanocomposites were enhanced. The dielectric permeability of the nanocomposite increased due to the interphase polarization, which in turn related to the formation of ordered structure caused the partial arrangement of carbon nanotubes in the polymer. Furthermore, the study showed that the negative magnetoresistance effect of PP+MWCNT+Fe3O4 nanocomposites is more dependent on the amount of Fe3O4 nanoparticles than that of MWCNT, which explained by the spin polarization of Fe3O4 nanoparticles at room temperature. In this research, the PP+5%Fe3O4+1%MWCNT nanocomposites were considered to be an effective material for magnetic field sensors and EMI shielding.