01.07.13
U.S. Patent No.: 8,222,477 B2
Inventor(s): Michael M. Azad, Reidsville, NC, U.S.; Scott J. Smith, Greensboro, NC, U.S.; Mark Joy, Reidsville, NC, U.S.; Geoffrey Wyatt Blake, Kernersville, NC, U.S.; and Michael S. Jarman, High Point, NC, U.S.
Company: Evonik Stockhausen, LLC, Greensboro, NC, U.S.
Issued: 7/17/12
Description
A superabsorbent polymer containing clay particulate comprising: a) a superabsorbent polymer particulate comprising an intimately admixed blend of from about 90 wt % to about 99.5 wt % of a superabsorbent polymer hydrogel and from about 0.5 wt % to about 10 wt % of a clay; wherein the admixed blend is dried and comminuted into superabsorbent polymer particulate; b) wherein the superabsorbent polymer particulate of a) is surface treated with from about 0.001 wt % to about 5 wt % of a surface crosslinking agent to form a surface crosslinked superabsorbent polymer particulate; c) wherein the surface crosslinked particulate composition of b) is surface treated with from about 0.01 wt % to about 5 wt % of a multivalent salt to form the superabsorbent polymer containing clay particulate; d) wherein the superabsorbent polymer particulate composition of b), c), or b) and c) is further surface treated with from about 0.01 wt % to about 5 wt % of a cationic polymer; and wherein the superabsorbent polymer containing clay particulate has a free swell gel bed permeability of at least about 10 Darcy, as measured by the Free Swell Gel Bed Permeability Test.
Inventor(s): Michael M. Azad, Reidsville, NC, U.S.; Scott J. Smith, Greensboro, NC, U.S.; Mark Joy, Reidsville, NC, U.S.; Geoffrey Wyatt Blake, Kernersville, NC, U.S.; and Michael S. Jarman, High Point, NC, U.S.
Company: Evonik Stockhausen, LLC, Greensboro, NC, U.S.
Issued: 7/17/12
Description
A superabsorbent polymer containing clay particulate comprising: a) a superabsorbent polymer particulate comprising an intimately admixed blend of from about 90 wt % to about 99.5 wt % of a superabsorbent polymer hydrogel and from about 0.5 wt % to about 10 wt % of a clay; wherein the admixed blend is dried and comminuted into superabsorbent polymer particulate; b) wherein the superabsorbent polymer particulate of a) is surface treated with from about 0.001 wt % to about 5 wt % of a surface crosslinking agent to form a surface crosslinked superabsorbent polymer particulate; c) wherein the surface crosslinked particulate composition of b) is surface treated with from about 0.01 wt % to about 5 wt % of a multivalent salt to form the superabsorbent polymer containing clay particulate; d) wherein the superabsorbent polymer particulate composition of b), c), or b) and c) is further surface treated with from about 0.01 wt % to about 5 wt % of a cationic polymer; and wherein the superabsorbent polymer containing clay particulate has a free swell gel bed permeability of at least about 10 Darcy, as measured by the Free Swell Gel Bed Permeability Test.