Conducting polymers IX: Optical properties, dielectric constants and conduction mechanism of poly(N,N′-Bis-salphinyl 2,6-diaminipyridine-3,5-diamini-1,2,4-trizole)

Abstract

Poly(N,N′-Bis-salphinyl 2,6-diaminipyridine-3,5-diamini-1,2,4-trizole) (PBDPT) is synthesized starting with 2,6-diamino-pyridine using thionyl chloride (SOCl2) as an oxidizing agent and then is polymerized with 3,5-diamino-1,2,4-triazole. The chemical structure of the produced PBDPT is confirmed by spectroscopic analyses techniques. The average molecular weight of PBDPT is determined using 1H NMR technique. The optical investigations of PBDPT showed two absorption peaks and two remarkable emission peaks. The oscillator strength of the absorption peaks is calculated and is found to be 4.4×1012 and 1.96×1012 for the peaks at 9.19×1014 and 7.54×1014Hz, respectively. The energy gap (Eg) is found to be 2.66eV. Direct current electrical conductivity (σDC), alternating current electrical conductivity (σAC) and conduction mechanisms are investigated in the temperature range 298–373K. The thermal activation energy for DC conductivity, ΔEDC, is determined and found to be 0.54eV while the thermal activation energy for AC conductivity, ΔEAC, is found to be in the range 0.09–0.17eV; depending on the test frequency. The semi-circle behavior of the impedance spectra confirmed that the equivalent circuit of the sample can be represented by a resistor Rp in parallel with a capacitor Cp.