Patent ID: 11958037
Assignee: LG CHEM, LTD.
Field: Macromolecular chemistry, polymers (Chemistry)
Classification: CPC B  C | IPC B  C

Claim 0:
1. A method of preparing a superabsorbent polymer, the method comprising:
forming a water-containing gel polymer by performing crosslinking polymerization of water-soluble ethylenically unsaturated monomers having acidic groups, of which at least part is neutralized, in the presence of an internal crosslinking agent including a compound represented by the following Chemical Formula 1, an encapsulated foaming agent, and a polymerization initiator;
forming a base polymer in the form of powder by drying and pulverizing the water-containing gel polymer; and
performing heat-treatment of only the base polymer,
wherein the encapsulated foaming agent is used in an amount of 0.1 part by weight to 0.4 parts by weight with respect to 100 parts by weight of the water-soluble ethylenically unsaturated monomer:, in Chemical Formula 1, R1 is a divalent organic group derived from alkane having 1 to 10 carbon atoms, and R2 is hydrogen or a methyl group.