Patent ID: 8802786
Filing Date: 2014-08-12
Classification: A61L,B01J,C08F,C08J,C08K

Abstract:
1. A particulate superabsorbent polymer composition comprising a polymer comprising: a) from about 55 wt % to about 99.9 wt % of polymerizable unsaturated acid group containing monomers; b) from 0 wt % to 40 wt % of polymerized, ethylenically unsaturated monomers copolymerizable with a); c) from about 0.001 wt % to about 5.0 wt % based on the weight of a) of an internal crosslinking agent, wherein the components a), b) and c) are polymerized into a hydrogel which is granulated into particulate superabsorbent polymer having a surface; d) from about 0.001 wt % to about 5.0 wt % based on the dry particulate superabsorbent composition weight of surface crosslinking agent applied to the surface of the particulate superabsorbent polymer; and e) from 0.01 wt % to about 5 wt % based on the dry particulate superabsorbent composition weight of a neutralized multivalent metal salt applied to the surface of the particulate superabsorbent polymer, wherein said neutralized multivalent metal salt further comprises an organic acid or its salt, wherein the molar ratio of said organic acid to the multivalent metal is between about 0.75:1 to about 1.5:1, and wherein the neutralized multivalent metal is in the form of an aqueous solution having a pH value from about 5.5 to about 7 wherein the superabsorbent polymer composition has a degree of neutralization of from about 50 mol % to about 80 mol %; and the particulate superabsorbent polymer composition have a Gel Bed Permeability of from about 30 Darcy to about 100 Darcy as measured by the Free-Swell Gel Bed Permeability Test as set forth herein; a Centrifuge Retention Capacity of from about 25 g/g to about 50 g/g as measured by the Centrifuge Retention Capacity Test as set forth herein, and an absorbency under load at 0.9 psi from about 16 g/g to 24 g/g as measured by the Absorbency Under Load Test (AUL(0.9 psi)) as set forth herein.