Hydration kinetics of the epoxy resin-modified cement at different temperatures

Hydration heat evolution rate and cumulative hydration heat of epoxy resin-modified cement were measured at 30 °C and 70 °C by isothermal calorimetry. Based on a new developed kinetics model, which supposed that nucleation and growth of the hydration product of cement takes place randomly on the surface of cement particles, the influence of epoxy resin on the hydration kinetics of cement was analyzed. The results illustrate that the early hydration of cement is retarded due to the formation of epoxy resin film on the surface of cement particles, which has been clearly observed by ESEM. The simulating results of kinetic parameters show that the retardation effect of epoxy resin mainly refers to the decreasing of nucleation rate of hydration product of cement at 30 °C. At 70 °C, both the nucleation rate and growth rate of nuclei are decreased due to the property modification of cement by epoxy resin. The degree of polymerization of epoxy resin has little influence on the hydration kinetics of epoxy resin-modified cement at 30 °C. But at 70 °C, the retardation effect of epoxy resin with high degree of polymerization is less obvious.