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Nickel oxide (NiO) nanoparticles (NPs) and graphene quantum dots (GQDs) reinforced polyvinyl alcohol (PVA) nanocomposite films were prepared using a solution casting technique. The physicochemical characteristics of PVA/NiO/GQDs (PNG) nanocomposite films were studied using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM). The obtained PNG nanocomposite films showed good mechanical flexibility and improved tensile strength. The influence of nanofiller concentrations on PNG nanocomposite film. The obtained results demonstrate an increase in the activation energy (Ea) up to PNG3 upon increasing the GQDs concentration and thereafter, its decreases. The fundamental interactions of the constituents of PNG nanocomposite film were investigated using density functional theory (DFT). This study on electronic structure reveals that the PVA model indirectly interacts with GQDs through the NiO model. This configuration is favoured in terms of interaction energy (-78 kJ/mol) compared to the one in which PVA interacts directly with the GQDs model., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The present work reports the preparation of polyvinyl formal (PVF)/Titanium dioxide (TiO 2 ) nanocomposite films using a solution casting method followed by the characterization of the synthesized PVF/TiO 2 nanocomposite films using various analytical techniques namely FTIR, XRD, UV-vis, SEM and TGA analysis. The results obtained from different analyses confirmed that the TiO 2 NPs was fine dispersed within the PVF matrix and there exists well compatibility among the polymer matrix and the nanofiller. The pristine TiO 2 NPs based fabricated chemiresistive sensor exhibits the maximum sensitivity of 50.25% at 370 °C where as PVF/TiO 2 nanocomposite sensor showed the enhanced sensitivity of 83.75% at a relatively low operating temperature of 150 °C towards 600 ppm sulfur dioxide (SO 2 ) gas. The 25 wt% PVF/TiO 2 nanocomposite film sensor exhibited good sensitivity (∼83.75%), selectivity, rapid response time (66 s)/recovery time (107 s), and long-term stability of 60 days for SO 2 gas detection. The fabricated PVF/TiO 2 nanocomposite film sensors in our work possesses the advantages of low power consumption, cost-effective, and distinguished sensing abilities for SO 2 detection makes it possible for potential applications. Thus, the fabricated chemiresistive sensors based on TiO 2 NPs reinforced PVF nanocomposites films are evaluated and experimental results to show an excellent behavior towards SO 2 gas detection for industrial processes control and environmental monitoring applications., Competing Interests: Declaration of competing interest All the authors declare no conflict of interest., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Polymer composites have established an excellent position among the technologically essential materials because of their wide range of applications. An enormous research interest has been devoted to zinc oxide (ZnO) based polymer nanocomposites, due to their exceptional electrical, optical, thermal, mechanical, catalytic, and biomedical properties. This article provides a review of various polymer composites consisting of ZnO nanoparticles (NPs) as reinforcements, exhibiting excellent properties for applications such as the dielectric, sensing, piezoelectric, electromagnetic shielding, thermal conductivity and energy storage. The preparation methods of such composites including solution blending, in situ polymerization, and melt intercalation are also explained. The current challenges and potential applications of these composites are provided in order to guide future progress on the development of more promising materials. Finally, a detailed summary of the current trends in the field is presented to progressively show the future prospects for the development of ZnO containing polymer nanocomposite materials., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The current work deals with the synthesis and characterization of strontium titanate (SrTiO3) nanoparticles reinforced polyvinyl chloride (PVC) and polyvinylidene fluoride (PVDF) blend nanocomposite films prepared via a solution casting approach. The structural, thermal, morphological characteristics of the PVC/PVDF/SrTiO3 nanocomposite films were explored through Fourier transform infrared spectroscopy- FTIR, X-ray diffraction–XRD, thermogravimetric analysis–TGA, scanning electron microscopy–SEM and atomic force microscopy–AFM. The electromagnetic interference (EMI) shielding efficiency (SE) of the PVC/PVDF/SrTiO3 nanocomposite films were investigated in Ku-band (12–18 GHz). The EMI shielding result demonstrated the enhancement in EMI SE values with an increase in the SrTiO3 loading. The PVC/PVDF/SrTiO3 nanocomposite exhibits the maximum EMI SE values ∼ − 12.51 dB at 10 wt% of SrTiO3 loading. These findings affirm the dominating absorption behaviour of the nanocomposite (73.9%) with an overall shielding ability of 99.6% and negligible transmittance. [ABSTRACT FROM AUTHOR]

In this study, zinc sulphide nanoparticles (ZnS NPs) have been synthesized by green synthesis approach. These ZnS NPs were used as nanofiller to fabricate polyvinyl alcohol (PVA) based nanocomposite films via solution casting method. The PVA/ZnS nanocomposite films have been characterized by X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, atomic force microscopy and thermogravimetric analysis. The results from these characterization techniques evidenced the improvement in structural, morphological and thermal properties of PVA/ZnS nanocomposite films and also confirmed the incorporation of ZnS NPs in the PVA matrix. In addition to that, the dielectric properties of the PVA/ZnS nanocomposite films were investigated for different frequencies (50 Hz-1 MHz) and temperatures (40-140 °C) using an impedance analyzer. The values of dielectric constant and dielectric loss of PVA/ZnS nanocomposite films were observed to be 328.93 (50 Hz, 140 °C) and 6.02 (50 Hz, 140 °C) with 3 wt% ZnS NPs content. This enhancement in dielectric properties demonstrated the good interaction between ZnS NPs and PVA matrix. The aforementioned results evidenced that the ZnS NPs were homogeneously distributed within the PVA matrix. [ABSTRACT FROM AUTHOR]

Germanium dioxide (GeO2) nanoparticles reinforced poly(vinyl chloride) (PVC) and poly(methyl methacrylate) (PMMA) blend nanocomposite films were prepared using solution casting technique. The PVC/PMMA/GeO2 nanocomposite films were characterized by FTIR—Fourier transform infrared spectroscopy, XRD—X-ray diffraction and TGA—thermogravimetric analysis. The morphological and structural characteristics were examined using POM—polarized optical microscopy, SEM—scanning electron microscopy and AFM—atomic force microscopy. The dielectric properties and the electromagnetic interference (EMI) shielding effectiveness of these nanocomposite films were also studied. The EMI shielding properties were studied in the broadband microwave region of X (8-12 GHz) and Ku band (12-18 GHz). From SEM micrographs, the porous network was unfolded that enriches the absorption behaviour. The EMI shielding effectiveness of − 17.1 dB was observed for PVC/PMMA/GeO2 nanocomposite film with 10 wt % GeO2 loading and the nanocomposite film with 8 wt% of GeO2 loading showed the potential to attenuate electromagnetic waves through absorption up to 75%. Hence, the EMI shielding results demonstrate that the PVC/PMMA/GeO2 nanocomposite films can be used as an absorption dominating shielding materials. [ABSTRACT FROM AUTHOR]

Poly(vinyl alcohol)/copper oxide/graphene nanoplatelets (PVA/CuO/Gr-NPls) nanocomposite based chemiresistive alcohol sensors were fabricated using colloidal blending method. The PVA/CuO/Gr-NPls nanocomposite films were characterized using Fourier transform infrared spectroscopy, X-ray diffraction, UV–Vis spectroscopy, thermogravimetric analysis, scanning electron microscopy, atomic force microscopy and the sensing behaviour of PVA/CuO/Gr-NPls nanocomposite films was evaluated for volatile organic compounds (VOCs). The improvement in the thermal, mechanical and VOCs sensing properties of nanocomposite film was observed attributing to the homogeneity of the nanocomposites and strong interfacial interaction between Gr-NPls, CuO and PVA matrix. The sensors were analyzed in the concentration range from 1800 to 4000 ppm. It was observed that PVA/CuO/Gr-NPls nanocomposite film exhibited excellent propanol sensing at a room temperature, typically at an applied voltage of 10 V when compared with other VOCs. Thus, the strong interaction between CuO and Gr-NPls helps in achieving excellent reinforcement effect in a PVA matrix for fabrication of high performance nanocomposite films for VOC’s sensing applications. [ABSTRACT FROM AUTHOR]

Polymer/inorganic nanocomposites comprising of hydroxypropyl methylcellulose and polyvinyl alcohol as a polymer matrix and unique combination of graphene oxide and zinc oxide nanoparticles as fillers have been prepared using colloidal processing technique and characterized using various analytical methods. The dielectric properties of the nanocomposites are investigated using impedance analyzer. The nanocomposites show improvement in the dielectric properties compared to hydroxypropyl methylcellulose/polyvinyl alcohol (50/50) blends, which results from the homogeneous dispersion of fillers into the polymer matrix. The results indicate that these nanocomposites have a potential to meet the technological demands of high-k dielectrics and/or embedded capacitors. [ABSTRACT FROM AUTHOR]