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In the present work, Zeolite 13X and carbon black nanoparticles (CBNPs) reinforced polyvinylidene fluoride (PVDF) nanocomposites were obtained by a simple solvent casting technique. The structural, morphological and thermal properties of PVDF/Zeolite 13X/CBNPs nanocomposites with various loadings of Zeolite 13X and CBNPs were investigated using Fourier-transform infrared spectroscopy, X-ray diffraction, Scanning electron microscopy and thermo-gravimetric analysis. The dielectric studies were carried out in the 50 Hz-10 MHz frequency range at room temperature. The electromagnetic interference (EMI) shielding effectiveness (SE) of PVDF/Zeolite 13X/CBNPs nanocomposite was investigated in the 8-18 GHz frequency region (X-band and Ku-band). The maximum EMI SE of approximately −11.1 dB (8-12 GHz) and −11.5 dB (12-18 GHz) was observed for PVDF/CBNPs nanocomposites with 10 wt% loading of CBNPs. These findings emphasize the application of PVDF/ Zeolite 13X/CBNPs nanocomposites as a potential EMI shielding material.

Polyvinyl alcohol (PVA)/polyethylene glycol (PEG) blend nanocomposite films reinforced with various loadings of carbon black nanoparticles (CBNPs) were synthesized via a solution casting approach. The structural properties of PVA/PEG/CBNPs nanocomposites were investigated using Fourier-transform infrared (FTIR) spectroscopy, indicating the strong interaction of CBNPs with the polymer blend. The thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) results respectively confirmed the enhanced thermal stability and the variation in the melting temperature with the addition of CBNPs in polymer blend . The dielectric measurements of nanocomposite films were carried out over a frequency range from 50 Hz–20 MHz at a varied temperature range from 40 °C–150 °C using impedance analyzer . The maximum dielectric constant for neat PVA was observed to be about 21.4 at 50 Hz and 150 °C. For PVA/PEG/CBNPs nanocomposites having higher loading of CBNPs (25 wt%) the maximum value of dielectric constant was found to be ε = 375.1 at 50 Hz, 150 °C. The dielectric properties increased with the addition of CBNPs which validates a significant control on percolation threshold attributing to the well-dispersed CBNPs in the polymer blend. The electromagnetic interference (EMI) shielding effectiveness (SE) was improved from 0.1 dB to 10.6 dB with the addition of CBNPs in the PVA/PEG blend. The improved EMI SE and dielectric performance of these nanocomposites suggest CBNPs as excellent nanofillers for the development of flexible, lightweight and low-cost material for electronic applications.

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Graphene quantum dots (GQDs) reinforced poly(vinyl alcohol) (PVA)/polypyrrole (WPPy) nanocomposite films with various GQDs loadings were synthesized using the versatile solvent casting method. The structural and morphological properties of PVA/WPPy/GQDs nanocomposite films were investigated by employing Fourier transform infrared spectroscopy, X‐ray diffraction, and scanning electron microscopy. The thermogravimetric analysis revealed enhanced thermal stability of synthesized nanocomposites while enhanced dielectric properties were also observed. The maximum dielectric constant value for PVA/WPPy/GQDs nanocomposite films was observed to be ε = 6,311.85 (50 Hz, 150°C). The electromagnetic interference (EMI) shielding effectiveness (SE) of nanocomposite films was determined in the X‐band (8–12 GHz) and Ku‐band (12–18 GHz) frequency region. The EMI SE was found to be increased from 0.8 dB for the pure PVA film to 9.8 dB for the PVA/WPPy/GQDs nanocomposite film containing 10 wt% GQDs loading. The enhanced EMI shielding efficiency of nanocomposite films has resulted from the homogenous dispersion of GQDs in PVA/WPPy blend nanocomposites. Thus, the prepared nanocomposites are envisioned to utilize as a lightweight, flexible, and low‐cost material for EMI shielding applications.