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Magnetic and electrically conductive polymeric nanocomposites were fabricated using polystyrene (PS) as matrix, Nickel Ferrites (NiFe) as magnetic nanofiller and polyaniline (PANI) as electrically conductive nanofiller. Electromagnetic interference (EMI) shielding and infrared (IR) blocking are the main application of these nanocomposites. PANI and NiFe were successfully prepared by chemical and co-precipitation methods respectively. The successful fabrication of nanofillers was confirmed by the X-ray diffraction technique. DC conductivity and dielectric properties were first analyzed and a huge increase in both dielectric constant and DC conductivity was observed. Dielectric Constant seemed to be increased from 2.2 for PS to 5.5 for PS/PANI/NiFe composite. For the measurement of EMI shielding effectiveness (SE), Vector Network Analyzer was used in 0.1-20 GHz frequency range. IR spectroscopy was used to measure IR transmission in near-infrared (NIR) region of 700-2500 nm wavelength range. PS film is transparent for both NIR waves and microwaves, by observing almost 90% transmission in the NIR range and about − 3 dB SE in the microwave region. IR transmission reduces to less than 0.5% for PS/PANI/NiFe composite in the whole NIR range. Also, in the microwave region, − 3 dB shielding enhanced to less than − 35 dB in a broad range of frequency from 0.1 to 20 GHz.

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The Electromagnetic Interference (EMI) shielding characteristics of PVC based nanocomposites were studied when reinforced with newly developed Thermally Reduced Graphene Oxide (TRGO) coated with Polyaniline (PANI) nanoparticles. Various techniques were utilized to characterize prepared nanocomposite films like Scanning Electron Microscopy (SEM), direct current (DC) conductivity measurement, impedance analyses, and EMI shielding. EMI shielding was measured in three different regions of the electromagnetic spectrum like the Microwave region (0.1 GHz to 20 GHz), Near InfraRed (NIR), and Ultraviolet region (UV). The coating of PANI over TRGO provides compatibility of nanoparticles with a polymer matrix that leads to enhanced dispersion. EMI shielding was found to be 104 dB for 40 wt% filler content, because of the formation of a mature and dense interconnected network structure of filler. UV and NIR transmittance was also studied and less than 0.5% transmission in the whole UV (200 nm 400 nm) and NIR (700 nm 2500 nm) region was observed.

Thermally reduced graphene oxide (trGO) was successfully prepared and confirmed by XRD then dispersed in polystyrene (PS) and Acrylonitrile-Butadiene-Styrene (ABS) polymers and evaluated for EMI shielding in microwave and infrared (IR) region. Thickness of prepared polymer/trGO composite films were 200-250 micron. It was observed that trGO has more compatibility with PS then ABS and dispersed more easily and uniformly in PS than ABS. This effect was also observed in IR shielding as ABS+15trGO have 3% transmission and PS+1% trGO have 1.5% transmission. Maximum 29 dB and 25 dB shielding effectiveness was measured by vector network analyzer (VNA) in microwave region (9-18 GHz) of PS+2% trGO and ABS+2% trGo composite respectively. These results clearly indicating that trGO is more compatible with PS than ABS and form more stable and mature interconnected network structure in PS at lower concentrations.