Kinetics of thermal degradation of water borne polyurethane dispersion containing polycaprolactone with either isophorone diisocyanate or metatetramethyl xylene diisocyanate

Abstract

Water borne polyurethane dispersions synthesized using poly caprolactone–isophorone diisocyanate combination and caprolactone–metatetramethyl xylene diisocyanate combination. Thermal stability of the polyurethane dispersions was studied using thermogravimetric technique. The activation energy of decomposition of these polyurethane dispersions was determined by applying classical kinetic models and isoconversional method. Though the classical kinetic models assume constant activation energy for any reaction, the activation energy determined is in good agreement with that obtained via isoconversional analysis. However, the advantage of isoconversional analysis is highlighted compared to classical kinetic models based on the mechanism delineating capacity of isoconversional analysis. The present work compares the thermal stability of the aqueous polyurethane dispersion formed from poly caprolactone–isophorone diisocyanate with caprolactone–metatetramethyl xylene diisocyanate.