Studies on the thermal stability of vinyl ester/polyurethane IPNs by gravimetric analysis

Interpenetrating polymer networks based on vinyl ester resin and polyurethane were synthesized using different blend ratio, for example, 93:7, 90:10, and 80:20 (w/w). The samples were subjected to thermogravimetric analysis under non-isothermal conditions in presence of an inert atmosphere within the temperature range of 303–773K. Determination of distributed activation energy at various stages of degradation process and its implication in the reaction mechanism was investigated by using various isoconversional models and Kissinger’s model fitting approaches. It was observed that IPNs showed higher thermal stability and also possessed higher activation energy for degradation than pure VE in the selected range of temperature when heated at a specific rate.