Electromagnetic parameters of composite materials based on polyethylene and multi-walled carbon nanotubes modified by iron oxide nanoparticles

Specifi c features are revealed of how composite materials are formed on the basis of polyethylene and multi-walled carbon nanotubes modifi ed with iron oxide nanoparticles (Fe3O4/MWCNT–PE), produced by the mechanical mixing method from a polyethylene melt. The conditions in which the composite materials are obtained were optimized to provide a uniform distribution of the Fe3O4/MWCNT fi ller in the polyethylene matrix. The infl uence exerted by the Fe3O4/MWCNT fi ller on the electrical properties of the resulting composite materials was determined. Introduction of Fe3O4 nanoparticles gives rise to magnetic properties of a composite material in the frequency range from 1 kHz to 2 MHz. An analysis of the frequency dependences of refl ectance, transmittance and absorbance demonstrated that an increase in the sample thickness leads to a higher refl ectance and lower transmittance. The composite materials can be used to create coatings lowering the electromagnetic radiation intensity by up to 40%. It was shown that increasing the content of Fe3O4/MWCNT to more than 10 wt % leads to a decrease in both the electrical conductivity and the complex dielectric permittivity and magnetic permeability of the composite material. This occurs due to the decrease in the fl owability of the polymer material and to the resulting nonuniform distribution of the fi ller in the bulk of polyethylene