Reaction Conditions, Photophysical, Electrochemical, Conductivity, and Thermal Properties of Polyazomethines

Abstract

In this paper, a series of Schiff bases and their polyazomethine derivatives were synthesized via condensation and oxidative polycondensation reactions of 4-aminophenol with 4-isopropylbenzaldehyde or 4-t-butylbenzaldehyde. Polymerization reaction conditions for polymerization yield of polyazomethines were investigated by changing some experimental parameters such as time and temperature using different oxidants like alkaline NaOCl (30%) and air. The structural characterizations of Schiff bases and polymers were performed using FT-IR, H-1 NMR, C-13 NMR and SEC techniques. Photophysical properties were studied UV-vis and photoluminescence spectroscopies. Electrochemical properties were also investigated cyclic voltammetry (CV) and electrochemical band gaps determined in the range 1.73 to 2.63 eV. Thermal properties of the compounds were investigated using TG-DTA and DSC techniques and char residue at 1000 degrees C determined between 3-6% and 39-34% for Schiff bases and polyazomethines, respectively. Moreover, conductivity measurements were done using four-point probe technique at both doped with iodine vapor and un-doped state.