Preparation and characterization of a high performance radiowave shielding material using fillers comprised of Pb(Mg1/3Nb2/3)O3–PbTiO3 (PMN-PT) (65/35), Zx+yFe9x–y+3O15x+4 (0 < (x,y) < 1) and ECM based on a polyamide matrix

Abstract

In the present study, a novel radiowave (RW) shielding material was successfully prepared based on polyamide (PA) using fillers including (i) electric conductive materials (ECMs) comprised of Cl-doped graphitic carbon nitrite (Cl-doped gC3N4), reduced graphene oxide (RGO) and polypyrrole (PPy), (ii) dielectric material comprised of Pb(Mg1/3Nb2/3)O3–PbTiO3 (PMN-PT) (65/35) and (iii) magnetic material comprised of Zx + yFe9x–y+3O15x+4 (0 < (x, y) < 1) (Z = Mg, Co, Ni), x = 1, y = 0, Z = Mg hexaferrites (MgFe12O19) and x = 0, y = 1, Z = Co and Ni spinel ferrite (NiFe2O4 and CoFe2O4)). X-ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometry (VSM) were utilized to characterize the crystal structures, morphologies and properties of the RW shielding material, respectively. The variables and their levels were optimized using Taguchi experimental design to achieve a shielding with higher RW absorption properties. The optimum conditions were determined as follows: 3 wt% PMN-PT, NiFe2O4 as the magnetic material, PPy as the ECM and a shielding thickness of 1 mm. Finally, the optimized RW shielding material exhibited good RW absorbent properties including impedance (Z) in the range of 210–400 Ω, reflection loss (RL) <–35 dB (absorption = 99.9%) and attenuation constant (α) of >2000 dB/m at a shielding thickness of 1 mm in the RW frequency range.