THERMAL DEGRADATION AND KINETIC ANALYSIS OF A SULPHANILIC ACID–MELAMINE–FORMALDEHYDE COPOLYMER FOR HIGH-PERFORMANCE INDUSTRIAL APPLICATIONS

Abstract

            The SAMF copolymer was prepared by the polycondensation of Sulphanilic acid, Melamine, and formaldehyde in a 1:1:4 molar ratio in the presence of 1 M HCl as a catalyst. Structural characterization of the synthesized copolymer was carried out using several physicochemical techniques, namely Ultraviolet–Visible spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, and proton nuclear magnetic resonance (¹H NMR) spectroscopy. The number-average molecular weight of the SAMF copolymer was determined by employing the non-aqueous conductometric titration method. Viscosity studies performed in DMF solvent indicated that the polymer solution exhibited normal behavior. The surface characteristics and morphological features of the copolymer were examined using scanning electron microscopy (SEM). Furthermore, kinetic parameters such as activation energy and reaction order (n), together with thermodynamic parameters including entropy change, Gibbs free energy change, apparent entropy, and frequency factor, were estimated employing the Freeman–Carroll and Sharp–Wentworth methods. The activation energy values derived from both methods were found to be in close agreement, whereas the reaction order was determined to be 0.90.