Dielectric properties of new fully conjugated 2H- and metal-pyrazinoporphyrazine network polymers
Article first published online: 12 APR 2011
Copyright © 2011 Wiley Periodicals, Inc.
Journal of Applied Polymer Science
Volume 121, Issue 6, pages 3579–3589, 15 September 2011
How to Cite
Abdel-Razik, H. H., El-Sayed, S. and Hassen, A. (2011), Dielectric properties of new fully conjugated 2H- and metal-pyrazinoporphyrazine network polymers. J. Appl. Polym. Sci., 121: 3579–3589. doi: 10.1002/app.34169
- Issue published online: 31 MAY 2011
- Article first published online: 12 APR 2011
- Manuscript Accepted: 10 JAN 2011
- Manuscript Received: 21 JUL 2010
- dielectric permittivity;
- ac conductivity;
- hopping conduction mechanism
2,7-Di-tert-butylpyrene was oxidized to 2,7-di-tert-butylpyrene-4,5,9,10-tetraone. The latter through condensation reaction with vicinal diamine such as diaminomaleodinitrile afforded heterocyclic monomer, 2,7-di-tert-butyl pyrene[4,5][9,10]bis(2,3-pyrazine-5,6-dinitrile), which was cyclotetramerized to the corresponding 2H- and metal-pyrazinoporphyrazine-based network polymers (2H-PyzPz and M-PyzPz, M = Co, Ni, Zn, or Cu). Elemental analytical results, Infrared, and NMR spectral data of the new prepared molecules are consistent with their assigned formulations. Molecular masses and metal contents of the synthesized polymers proved to be of high molecular masses, which confirm the efficiency of tetramerization polymerization and complexation reactions. Dielectric permittivity, ε′, loss tangent, tan δ, and ac conductivity, σac(ω), of 2H-PyzPz and M-PyzPz films were studied as a function of temperature and frequency. It was found that dielectric permittivity, ε′, decreases with the increase of frequency and increases with the increase in temperature. Ac conductivity, σac(ω), is found to vary as Bωs and the frequency exponent, s, is less than unity around room temperature indicating a dominant hopping process. On the other hand, σac(T) of all samples is thermally activated with low activation energies. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.