Curing Kinetics of TDI/PTMEG-based Urethane Prepolymers Depending on the Amount of Curing Agent and Curing Temperatures by DSC and Real Time FT-IR Spectroscopy

This study describes the influence of the amount of curing agent and curing temperature on the kinetics of poly-urethane elastomers. The urethane prepolymer series was prepared by reacting toluene diisocyanate with polytetramethylene ether glycol at 80°C for 1 h, and 4,4’-methylene bis(2-chloroaniline) was used as the curing agent. The ratio of the amine group of the curing agent to the isocyanate group of the urethane prepolymer was controlled from 0.85 to 1.05 at curing temperatures ranging from 80 to 120°C. The curing rate of the urethane prepolymer was monitored by observing the change in heat flow during the curing process using differential scanning calorimetry (DSC). As either the content of curing agent or the curing temperature was higher, the conversion rate to the polyurethane elastomer was high. The DSC results were compared with those obtained from using real-time FT-IR.