الفهرس 
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Abstract
The present work involved the preparation of composite derivatives from phosphate glass and polyaniline together with additional doped samples containing increasing CuO or ZnO (3→10 mol%). All prepared pure glass and polyaniline together with their composites were characterized by structural FTIR analysis, X-ray diffraction examinations and surface scanning electron microscope (SEM). Further antimicrobial properties of the base glass, base polyaniline and composites with one of the two dopants (CuO,ZnO) were studied and evaluated. FT infrared spectrum of the base undoped glass revealed vibrational bands due to PO4 tetrahedral groups which are extended from 400 cm-1 to 1500 cm-1 within the mid region. The base polyaniline exhibits extended vibrational bands characteristic for vibrations of C - C, C - H, C = C and N - H groupings. The composite (glass + polyaniline) showed mixed or interfering vibrations of all constitutional groupings. The dopant oxides showed only limited variations to the IR spectra. X-ray diffraction patterns of base and doped glass samples revealed only undefined humps with no indication for crystalline species but only amorphous structures. On the other hand, polyaniline revealed diffraction peaks which were correlated with crystalline components of the polymerized granular texture of the (PANI). SEM investigations revealed mostly amorphous texture for the parent glass and its derivatives but the polyaniline exhibited granular texture which extended to all composites in different forms. Glass and polyaniline composites showed varying responses to microorganisms. In general, the composites showed favourable data and better results than the individual glass or polyaniline.
The dielectric properties of different composite derivatives prepared from the two mixed phosphate glass and polyaniline (PANI) together with 7 mol% CuO or 7 mol% ZnO have been investigated over a wide frequency range at room temperature by means of the dielectric spectrometer. The permittivity is found to be increased with increasing frequency and becomes almost constant at higher frequencies whereas the conductivity shows a transition from the frequency independent DC conductivity to the dispersive frequency dependent AC conductivity. The conductivity continuously increases with increasing frequency obeying the universal power law. The dielectric properties of the studied samples are suggested to be dominated by the space charge polarization at low frequency as well as phenyl and NH2 groups at higher frequency. Interestingly, 7 mol% CuO-doped glass/PANI composite exhibited superior dielectric properties, i.e. low dielectric loss tangent (0.11), giant permittivity (16000) and high AC conductivity (6.8×10-4 S/cm). These collected dielectric properties make the prepared composite promising in the field of energy generation and storage.