Rheokinetic changes during polyurea reactions in solution

The viscosity rise and conversion profile of polyurea reaction in solution were measured using a Haake viscometer and an FTIR, respectively. In a three‐component polyurea system, it was found that the liquid–solid transition is dominated by the microphase separation from the formation of hard segments. The formation of soft segments mainly contributes to the initial viscosity buildup. A series of experiments were carried out to study the effects of resin composition, solvent concentration, and reaction temperature on the viscosity rise and gelation of polyureas.