SUPER ABSORBENT POLYMER AND ITS PREPARATION METHOD

摘要

The present invention relates to a superabsorbent resin having excellent physical properties with enhanced gel strength, centrifuge retention capacity (CRC) and absorptivity under pressure (AUP) through having an optimized crosslinking structure of base resin powder inside a surface crosslinking layer, and to a preparation method of the same. The superabsorbent resin comprises: a base resin powder including a first crosslinked polymer of a water-soluble ethylene-based unsaturated monomer having acid groups which are at least partially neutralized; a second crosslinked polymer which is formed by additionally crosslinking the first crosslinked polymer; and a surface crosslinking layer formed on the base resin powder. The first crosslinked polymer can be chemically bonded to inorganic particles through crosslink bonding, oxygen bonding or nitrogen bonding (-NR-; R is an alkyl group or an amide bond having hydrogen or carbon number of one to three).