Modeling and simulation of urethane acrylates synthesis. I. Kinetics of uncatalyzed reaction of toluene diisocyanate with a monoalcohol

Toluene diisocyanate (TDI) reacts with 2-hydroxyethyl acrylate (HEA) during the synthesis of some urethane acrylate oligomers. The present work deals with kinetic studies of the uncatalyzed bulk reaction of TDI with this monoalcohol. Back-titration and 1H -NMR in combination with HPLC are used to follow the reaction and allow a complete description of the system. The global reaction rate as well as those of each individual isocyanate group are well described by a second-order equation. Kinetic constants were calculated using the software SIMULBATCH®. The rates of the different isocyanate groups, which characterize their selectivity, are compared and the model developed in the present study allows for a good prediction of the product structure and a better control of the polymerization process and the end-use properties as well.