Polymer blend based on polyvinylidene fluoride (PVDF)/polymethyl methacrylate (PMMA) and the blend incorporated with low content ( £ 0.08) of graphene (GN) oxide were prepared. The characteristic bands for PVDF and PMMA were detected in Raman and IR spectroscopy. There are shifts in Raman and IR spectra due to interaction between the polymer and the blend with OH and C5O in GN oxide. The TGA thermograms show main weight loss in temperature range from 3218C to 4818C attributed to thermal decompositions of polymeric chain. The thermal decomposition was shifted toward higher temperature than that the blend confirms enhancement of thermal stability of the films. The AC electrical conductivity and kinetic parameters were measured at different temperature frequencies. The addition of GN increases the conductivity. The values of e 00 are high at low frequencies and it is decrease with increase frequencies due to polarization effects or to the dipoles not begin to follow the field variation at higher frequencies. The increase in tan d with increase in GN oxide content due to interfacial polarization mechanism occurred in the films corresponding to frequencies. All results data indicate that the nanocomposites contain GN were enhanced.

Films of polymethyl methacrylate (PMMA)/polycarbonate (PC) polymer blend doped silicon carbide (SiC) nanopowder are synthesized by the casting method. The study for the structural, optical and electrical behavior of PMMA/PC blend without and with low contents (≤0.8 wt%) of SiC is done. The change of the structure is investigated from X-ray spectra. After the addition of SiC, the intensity of the main X-ray halo peak at 2θ = 20.26˚ of PMMA/PC is decreased, attributed to an interaction between PMMA/PC. It's clear that SiC is causing an increase in the amorphous regions inside the PMMA/PC blend. The peaks related to SiC are not found attributed using a small amount of SiC with complete dissolution of SiC. The shift of the intensity for IR bands has supported an interaction between all components. The values of the optical band gap from UV-Vis spectra using indirect transition are decreased with the increase of SiC. The values of the electrical conductivity are low at low frequency attributed to the charge accumulation at the electrode which takes place. The conductivity is increased as the increase of frequency due to the mobility of charge carriers. Furthermore, the conductivity is increased with the increase of SiC contents. The values of ε ′ and ε ′′ are very high at the lower frequency and they decrease when the frequency is increased attributed to the effect. The plot of both Z ′ and Z ′′ shows dramatic decrease with the increase of frequency.

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