Synthesis, characterization, optical and electrochemical band gaps of green poly(azomethine-ester)s containing oxalyl and succinyl units

A new series of poly(azomethine-ester)s (PAZ-E)s with different (turning ortho, meta and para) positions were synthesized by condensation polymerization. The chemical structure of polymers was verified by $$¹$$ H-NMR, $$¹³$$ C-NMR, FTIR and UV–Vis measurements. Electrochemical characteristics of the corresponding polymers were obtained with cyclic voltammetric (CV) analysis. Thermal characteristics of the obtained polymers were analysed by TG-DTA, DMA and DSC measurements. The first degradation temperature values of PAZ-E compounds were found between 198 and $$250{^\circ }\hbox {C}$$ from TGA measurements. Photophysical characteristics of the obtained polymers were explained with photoluminescence (PL) spectroscopy. Molecular weight distributions of (PAZ-E)s were obtained by gel permeation chromatographic (GPC) analysis. Two- and three-dimensional (2D and 3D) properties and images of the synthesized (PAZ-E)s were analysed by SEM and AFM surface analysis techniques, respectively. Electrochemical band gap ( $${E}^\prime _{\mathrm{g}}$$ ) values of (PAZ-E)s P-9, P-10, P-11, P-12, P-13 and P-14 were calculated as 2.58, 2.14, 1.90, 2.06, 1.89 and 1.69 eV, respectively. The $${E}^\prime _{\mathrm{g}}$$ values of the (PAZ-E)s were found to be quite low.