Water-soluble branched polymer as well as preparation method and application thereof

The invention discloses a water-soluble branched polymer and a preparation method thereof. The preparation method comprises the following steps: (1) dissolving acrylamide in water and adding a cerium salt to have a reaction; (2) adding a hydroxyl-terminated polyetherester polyol and the cerium salt to the reaction system in the step (1) and continuing reacting: (3) continuously adding the acrylamide and a fluorocarbon amphiphilic surfactant to the reaction system in the step (2) and continuing reacting; and (4) putting the reaction system in the step (3) in an oven, and then adding sodium hydroxide to have a hydrolysis reaction, thereby obtaining the water-soluble branched polymer. The water-soluble branched polymer is prepared by use of an oxidation-reduction initiating system which is composed of the cerium salt and a hydroxyl terminal, and then the polymerization of the free radicals of the acrylamide is directly initiated to obtain a water-soluble hyper-branched multi-arm copolymer. The preparation method of the water-soluble branched polymer employs a post-curing and post-hydrolyzing process, and the obtained product is stable in performance.