Water-in-water polymer dispersion and preparation method thereof

The invention provides a water-in-water polymer dispersion and a preparation method thereof. The water-in-water type polymer dispersion comprises, by weight, 800-950 parts of a monomer solution; 50-200 parts of a continuous phase solution; and 1-20 parts of a reducing agent. The preparation method comprises the following steps: firstly, adding part of THE monomer solution into THE continuous phase to form a water-in-water system, then adding an initiator to initiate polymerization, continuously controlling the system at medium and low temperatures through refrigeration, and continuously and slowly dropwise adding the residual monomer solution after the temperature is stable, so as to prepare the water-in-water polymer dispersion with high effective content. The problems of low water-in-water polymer content, easiness in demulsification to form gel, poor stability and the like are solved, and stable-quality, high-content, safe and controllable production is realized. 本发明提供了一种水包水型聚合物分散体及其制备方法，所述水包水型聚合物分散体，包括以下重