الفهرس 
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Abstract
In the present work Polyacrylonitrile-homopolymer and its metal complexes such as Cu, Ni, Co, and Fe are prepared by electrochemical polymerization technique. The prepared samples are investigated by elemental analysis, IR, UV-visible, and X-ray spectroscopies.
The fabricated samples exhibited the formation of different amorphous-like structures depending on the current density of preparation. The molecular weight obtained from the viscosity measurements is enhanced with increasing the current density.
Thermogravimetric analysis emphasized that the synthesized homopolymer and its complexes are stable up to a temperature of 255 oC. The glass-transition temperature, Tg, is found to lie in the temperature range from 90 oC to 100 oC. All the formed samples are found to be soluble in organic solvents (DMF, DMSO).
It is seen from the UV-visible spectra that the optical energy gaps for homopolymer and its complexes decrease with enhancing the current density. It is also found that the optical energy gaps associated with the MPAN-metal samples are lower in magnitude than those associated with homopolymers that fabricated at the same current densities. The optical measurements indicated the presence of a well-defined transition which may be attributed to л- л* transition.
The dielectric spectra for homopolymer and its complexes have been investigated and showed that the dielectric constant decreases with increasing both frequency and current density of preparation. The relaxation time and its associated activation energy are also determined from the loss factor spectra.
The a.c. conductivity for the present samples are measured for a frequency range from 50 mHz to 100 kHz and a temperature range that is varied from ~ 300 K to 474 K. Three characteristic behaviors associated with frequency are found.
Furthermore, the electric modulus spectra for MPAN- homopolymer and its metal complexes are performed, which present an alternative method for the measurements of the a.c. conductivity and the dielectric spectra. The electric loss modulus spectra showed a frequency independent region from which the glass-transition temperature is determined which is in good agreement with that found from the DSC analyses.