抄録
The study of waterborne dispersions of polymer resins with zero or low content of harmful organic compounds has much attention due to increasing of environmental and ecological legislative pressures. Waterborne polymer dispersion is a colloidal system of discrete polymer particles disperse in an aqueous continuous medium. Stable aqueous dispersions of polyurethane anionomer were successfully prepared by phase inversion emulsification. Phase inversion is induced by increasing the fraction of the dispersed phase to change the phase ratio in a liquid-liquid dispersion until the dispersed phase become the continuous phase. In this presentation here, water was added to polyurethane anionomer until the water became the continuous phase. As the phase inversion was complete, all water droplets in the system were simultaneously transformed into the continuous phase and discrete waterborne particles of polyurethane were formed. The rheological behaviors, torque change measurements, during the phase inversion process were characterized to detect the phase inversion point. The maximum torque change was considered as the character of phase inversion in the process of emulsification. The effect of stoichiometric formulation and molecular weight of polyol on the particle size and phase inversion behaviors will be discussed.
