The transition from batch to continuous polyurethane (PU) process is considered for process intensification. An integrated methodological and technological study is proposed. The development of the new process is based on modeling and product characteristics. In order to do so, the kinetics of the polyaddition of polycaprolactone diol (polyol) and 4,4'-diphenylmethane diisocyanate were studied and identified by using offline measurement of the diisocyanate concentration. Some characteristics of the final polymer were also investigated, such as the heat capacity and viscosity that affect the behavior of the continuous process. These results were used to design a tubular reactor for continuous production of PU. Since online monitoring of intensified processes is primordial, in situ near-infrared spectroscopy was used to predict the concentration of free diisocyanate in real time.