Preparation method of waterborne polyurethane dispersion

The invention relates to the technical field of polyurethane preparation, in particular to a preparation method of a waterborne polyurethane dispersoid, which comprises the following steps: S1, pretreating a polyurethane raw material; s2, carrying out a reaction to prepare polyurethane; s3, dispersing the polyurethane; s4, refining and filtering; and S5, packaging and storing. Equipment involved in the step S3 and the step S4 comprises a reaction cylinder, a partition plate, a stirring mechanism and a filtering mechanism. An external motor I drives a rotating shaft to rotate, and a V-shaped plate is meshed with teeth through a corresponding driving gear, so that the V-shaped plate revolves around the rotating shaft and rotates at the same time, a polyurethane raw material and a reactant are stirred, and the polyurethane raw material and the reactant react conveniently; meanwhile, one side of the two sides of the V-shaped plate is made to be tightly attached to the upper end face of the partition plate through