Isothermal curing of the glycidyl azide polymer binder system by microcalorimetry

Microcalorimetry was used to monitor the heat flow of the curing reaction between glycidyl azido polymer (GAP) and various isocyanate curatives. The curing kinetics was investigated in the temperature range 308.15-323.15 K, and the activation energy, activation free energy, activation enthalpy, and activation entropy of the curing reaction between GAP and polyaryl polymethylene isocyanate (PAPI) were obtained. The thermodynamic properties of the reaction were also studied by varying the amount of PAPI at 323.15 K. The rate constant slightly increased with the increasing content of PAPI. Moreover, a model function of da/dt = 10−4.30 (1-a)1.62 was applied to describe the curing reaction of the GAP-PAPI binder system at 323.15 K.