US 11,655,318 B2
Super absorbent polymer
Sang Gi Lee, Daejeon (KR); Hye Mi Nam, Daejeon (KR); Min Ho Hwang, Daejeon (KR); Soo Jin Lee, Daejeon (KR); and Tae Hwan Jang, Daejeon (KR)
Assigned to LG Chem, Ltd.
Filed by LG Chem, Ltd., Seoul (KR)
Filed on Sep. 30, 2020, as Appl. No. 17/38,957.
Application 17/038,957 is a division of application No. 15/564,487, granted, now 10,822,441, previously published as PCT/KR2016/006202, filed on Jun. 10, 2016.
Claims priority of application No. 10-2015-0084371 (KR), filed on Jun. 15, 2015.
Prior Publication US 2021/0061932 A1, Mar. 4, 2021
Int. Cl. C08F 220/06 (2006.01); C08J 3/075 (2006.01); C08J 3/12 (2006.01); C08J 3/24 (2006.01); C08J 9/08 (2006.01); C08F 220/10 (2006.01); C08F 2/44 (2006.01); B01J 20/26 (2006.01); B01J 20/28 (2006.01)
CPC C08F 220/06 (2013.01) [B01J 20/267 (2013.01); B01J 20/28004 (2013.01); C08F 2/44 (2013.01); C08F 220/10 (2013.01); C08J 3/075 (2013.01); C08J 3/12 (2013.01); C08J 3/24 (2013.01); C08J 9/08 (2013.01)] 5 Claims
 
1. A method for preparing a super absorbent polymer comprising:
carrying out a crosslinking polymerization of a monomer mixture comprising a water-soluble ethylenically unsaturated monomer having at least partially neutralized acidic groups, a forming agent, a foam-promoting agent and a silicone-based surfactant in the presence of an internal crosslinking agent to form a hydrogel polymer;
drying, pulverizing and classifying the hydrogel polymer to form a base polymer powder; and
further crosslinking a surface of the base polymer powder in the presence of a surface crosslinking agent to form a surface crosslinked layer.