Patent ID: 11383221

Abstract:
The present disclosure relates to a preparation method of a super absorbent polymer capable of improving absorption performance of the super absorbent polymer by adding a simple additive later. The preparation method includes the steps of: forming a hydrogel polymer by cross-linking and polymerizing a water-soluble ethylene-based unsaturated monomer having at least partially neutralized acidic groups in the presence of an internal cross-linking agent; drying, pulverizing and classifying the hydrogel polymer to form a base resin powder; forming a surface cross-linked layer by further cross-linking a surface of the base resin powder in the presence of a surface cross-linking agent, adding a monovalent to trivalent metal cation on the surface cross-linked base resin powder at a temperature of 25° C. to 80° C., and maintaining and aging the resulting metal cation-added product at a temperature of 40° C. to 60° C. for 10 to 30 minutes.