Dielectric Behavior of Thin Films made from poly(oxadiazole-naphthylimide)s

Abstract Oxadiazole-containing poly(naphthylimide)s were prepared by polycondensation reaction and their solid-state properties were investigated. Flexible films having good mechanical properties were made therefrom. The tougher polymer films were the subject of electrical insulating properties measurements. The dielectric constant values, measured at room temperature and in the frequency domain of 1 Hz–1 MHz, are in the range of 2.63–3.24, being lower or comparable with those of Kapton HN measured under the same conditions. The dielectric loss values are low, in the same range with those of Kapton HN. The dielectric spectroscopy data showed distinct subglass transitions for these polymers: γ relaxations with activation energies of 35 and 46 kJ/mol, and a β relaxation with the activation energy of 86 kJ/mol. Keywords: Poly(oxadiazole-naphthylimide)sTensile testsDielectric properties ACKNOWLEDGMENTS One of the authors (M. D. Damaceanu) acknowledges the financial support of European Social Fund—"Cristofor I. Simionescu" Postdoctoral Fellowship Programme (ID POSDRU/89/1.5/S/55216), Sectoral Operational Programme Human Resources Development 2007–2013. R. D. Rusu is grateful for the financial support provided by CNCSIS-UEFISCDI through Romanian Program PN II-RU, code TE-221, no. 31/10.08.2010.