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Lead oxide nanoparticles (PbO NPs) and carboxymethyl cellulose (CMC)/polyvinylpyrrolidone (PVP) nanocomposite films were prepared by sol‐gel and solution casting methods respectively. The structural properties of the samples were investigated by X‐ray diffraction (XRD), high‐resolution transmission electron microscopy (HR‐TEM) and Fourier transformation infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) revealed the good dispersion of PbO NPs on the surface of the blend films. CMC film exhibits a transmittance (T) of 72%, increased after mixing with PVP and then decreased to <38% after adding 4.0 wt% PbO NPs. Both the direct and indirect optical band gaps (Eg) of CMC equal to 3.97 and 3.7 eV, respectively. These values were increased after PVP addition and then decreased after loading PbO NPs. The conduction mechanism in CMC/PVP blend has changed from Schottky emission to Poole–Frenkel due to the effects of temperature and PbO NPs content. The effect of adding PVP & PbO NPs on the DC conductivity and the activation energy Ea values of the CMC are discussed. The dielectric constant (ε′) was investigated in the frequency and temperature ranges of 1 kHz–1.0 MHz and 293–393 K respectively. Its values depend on both the PbO content and temperature. The AC conductivity σac was increased with increasing PbO content. The correlated barrier hopping (CBH) was found to be the most appropriate mechanism for explaining the AC conduction behavior. POLYM. COMPOS., 39:3712–3725, 2018. © 2017 Society of Plastics Engineers

Magnesium oxide/polyvinyl alcohol/polyacrylamide (MgO/PVA/PAM) nanocomposite films were prepared via a solution chemical method. The effect of PVA and MgO nanoparticles (NPs) loading on the physical properties of PAM is discussed. X-ray diffraction reveals that the average MgO crystallite size of the NPs is ∼25 nm, while adding PVA increases the crystallinity of PAM. FTIR spectra confirm the interaction between blend chains and MgO NPs. Differential scanning calorimetry thermograms illustrate the miscibility between the PVA and the PAM. The melting temperature, the glass transition, as well as the equilibrium swelling ratio, depend on the films' composition. PAM showed a transmittance of 87%, that increased to 90% after PVA addition, but decreased to 74% after MgO loading. Meaningful changes are observed in the extinction coefficient and indirect/direct band gap of PAM due to PVA blending and MgO addition. The influence of MgO NPs on the dielectric constant ( ɛ′) of the blend film is reported. The maximum value of AC conductivity of the blend is 4.77 × 10−3 Sm−1, which increased to 8.07 × 10−3 Sm−1 by increasing the MgO loading to 5.0 wt.%. The conduction mechanism changed from the correlated barrier hopping, in the blend, to the large Polaron tunneling with MgO loading. The observed improvements in optical properties and AC conductivity encourage the use of these nanocomposite films in the semiconductors industry.