Method for preparing high solid content aqueous polyurethane emulsion by continuous process

The invention provides a method for preparing water-borne polyurethane emulsion with high solid content by the continuous method. The method comprises the following steps that: oligomer polylol after vacuum dehydration, isocyanate, a chain extender, a solvent and a catalyst are added into a reactor at a time under the protection of dry nitrogen; the mixture is mechanically stirred and simultaneously controlled at a certain temperature for reaction to a certain degree; the system temperature is reduced to between 20 and 50 DEG C; the hydrophilic chain extender is slowly dripped into a prepolymer which is then added with the solvent so as to prevent gel coagulation caused by overlarge viscosity; the isocyanate-based NCO content in the prepolymer which is generated through reaction is not changed again; and the prepolymer is added with water again to perform emulsion dispersion and undergoes vacuum distillation to remove the solvent, and then the water-borne polyurethane solution is prepared. The water-borne polyurethane solution prepared by the method has high solid content, low viscosity, large initial bonding strength, and good heat resistance, can be used as textile fabric coating agent, shoe coating agent, leather finishing agent, and adhesives used in the fields of wood, architecture, automobile, paper-making, electronics and so on.