Synthesis, characterization, reaction conditions, conductivity and thermal properties of poly(phenoxy-imine)s containing methoxy unit

Abstract

Two Schiff bases were accomplished through a condensation reaction between salicylaldehyde and ortho-anisidine or para-anisidine. The oxidative polycondenzation reaction conditions of 2-[(2-methoxyphenylimino)methyl)phenol (SB1) and 2-[(4-methoxyphenylimino)methyl] phenol (SB2) were determined by H2O2, NaOCl, and air oxidants in an aqueous alkaline medium at different temperatures and reaction times. The % conversion ratios (oligo-2-[(2-methoxyphenylimino)methyl)phenol (oligo-SB1) and oligo-2-[(4-methoxyphenylimino) methyl]phenol (oligo-SB2) were studied in optimum reaction conditions. The structural characterizations of compounds were defined with 1H- 13C-NMR, FT-IR, and size exclusion chromatography (SEC) measurements. Electrochemical and thermal features of compounds were studied by UV–Vis spectroscopy, cyclic voltammetry (CV), FE-SEM, and TG-DTA, respectively. Moreover, conductivity and surface morphologies measurements of oligo-SB1 and oligo-SB2 were carried out by four-point probe technique and FE-SEM, respectively. The conductivity values of the oligo-SB1 and oligo-SB2 were found to be 4.12×10−6 S cm−1 and 4.87×10−4 S cm−1, respectively. The residue amounts of oligo-SB1 and oligo-SB2 at 1000 °C were found as 45.52% and 55.46%, respectively. Thermal stability, optical properties and conductivity values of oligo-SB2 were better than oligo-SB1.