Engineering analysis of Reaction Injection Molding (RIM) process of polyurethane was carried out by simultaneously solving the balance equations of Mass, Momentum, and Energy by a computer simulation.
The polyurethane system evaluated was the reaction system of 4-4' diphenyl methane diisocyanate (MDI) and poly(propylene glycol) ($\bar{Mn}$:752) catalyzed by dibutyl tin dilaurate (T-12).
Basic data for simulation, such as the reaction rate constants and the viscosity variations on time were obtained emperically by running adiabatic reaction.
Temperature and conversion profiles at different points of the mold under constant temperature of heat transfer medium condition were obtained through computer simulation.
The effects of reaction rate constant at feed temperature, flow rate, heat of reaction, mold thickness, thermal conductivity, and overall heat transfer coefficient of the mold were discussed.
Actual Reaction Injection Molding experiment using acrylic mold with dimension of 20L*4W*0.5T(in cm) was conducted and temperature profiles at 5 different locations were obtained.
The actual temperature profiles were compared with computer simulation.
