Acid catalyzed resin: Physico-chemical and its thermal degradation studies

Abstract

Aims

Terpolymer (BPEDF) has been synthesized by the condensation of the monomers 2, 2′- biphenol, ethylene diamine and formaldehyde in 1:1:2 molar proportions in the presence of 2 M HCl as a catalyst.

Methods

The purity of newly synthesized resin has been tested and confirmed by the thin layer chromatography (TLC) technique. The structure of BPEDF has been elucidated on the basis of elemental analysis and various physicochemical techniques, i.e. FTIR, ¹HNMR, and UV–Visible spectral studies.

Result

Detailed thermal degradation study of the new terpolymer has been carried out to ascertain its thermal stability. The thermal degradation curve shows three decomposition steps (40–210 °C, 220–410 °C and 410 °C–900 °C). The thermal degradation curve was examined in order to determine their mode of decomposition, order of reaction, apparent activation energy, frequency factor, free energy change, entropy change and apparent energy change. Sharp–Wentworth and Freeman–Carroll methods have been used to calculate activation energies and thermal stability. The activation energy (25.84 KJ/mole⁻¹) calculated by using the Sharp–Wentworth method has been found to be in good agreement with that calculated by Freeman–Carroll method (23.11 KJ/mole⁻¹). The decomposition temperature is found to be 251 °C. The order of reaction (n) is found to be 0.95.