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This paper reports the formation of BaTiO 3 /CoFe 2 O 4 (BT-CFO) filled lowdensity-polyethylene (LDPE) composite via the process of melt mixing and characterization for their dielectric and electromagnetic shielding behaviors. The X-Ray diffraction (XRD) result of synthesized CoFe 2 O 4 shows the cubic phase structure formation with a crystallite size of 28.6 nm. The BT nanopowder and synthesized nanopowder of Cobalt ferrite (CFO) were mixed together in an equal amount (50:50), and sintered at 800 C for 1 hour. A series of samples of BT-CFO was prepared by taking a different amount of BT-CFO (ie, 4, 8, 12, 16, and 20 wt%) with LDPE. The dielectric measurements of BT-CFO/LDPE composites were carried out at different temperatures using LCR meter at a frequency range from 40 Hz to 5 MHz. The dielectric behaviour of samples exhibited a change in dielectric constant with an increase in temperature and frequency. The electromagnetic shielding measurements were examined over X-band with a frequency range from 8.2GHz to 12.4GHz of the prepared BT-CFO/LDPE composites. The EMI shielding effectiveness of prepared BT-CFO/LDPE composites exhibited a maximum value of 17.9 dB.

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This study reports the preparation of nickel ferrite (NiFe2O4) and copper ferrite (CuFe2O4) filled low-density polyethylene (LDPE) composite through a melt mixing process for employing in electromagnetic shielding applications. The X-Ray diffraction (XRD) with different pH values 6, 8 and 10 resulted the formation of cubic structure for NiFe2O4 of cristallite size 21 nm, 25 nm and 40 nm, respectively and tetragonal structure for CuFe2O4 with crystallite size 27 nm, 24 nm and 91 nm, respectively. Electromagnetic interference (EMI) shielding measurements of the prepared samples LDPE/NiFe2O4 and LDPE/CuFe2O4 having different pH values 6, 8 and, 10 for 10% and 30% filler concentrations were analyzed over X-band with a frequency range from 8 GHz to 12.4 GHz. The pure LDPE exhibits the total shielding effectiveness (SE) of 11.6 dB whereas with the addition of NiFe2O4 and CuFe2O4, the composites exhibit increment in EMI shielding effectiveness up to the maximum value of 15.3 dB for LDPE/NiFe2O4 and 12.6 dB for LDPE/CuFe2O4 respectively.

Nickel and Copper ferrite of different compositions have been synthesized by wet co-precipitation technique. The synthesized samples were annealed at 800ºC for 4 hours and characterized by X-Ray Diffraction (XRD) analysis. The XRD pattern confirms the formation of a cubic structure with the crystalline size for nickel ferrite 23nm and copper ferrite 37nm. The composite has been synthesized with the various compositions (10wt% and 30wt%) of nickel ferrite and copper ferrite with pH values 6, 8 and 10 in LDPE. The Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray spectrum (EDAX) confirms the homogeneous mixing of the composite material. The dielectric measurement has been carried out as a function of frequency at room temperature in the range of 1Hz-8MHz. The dielectric behaviour of Nickel ferrite and Copper ferrite based LDPE composite results decrease in dielectric constant and dielectric loss factor with the increase in frequency.