Patent ID: 7906585

Claim:
A method to make a superabsorbent polymer composition comprising the steps of: a) preparing a superabsorbent polymer by the process of polymerizing from about 55 to about 99.9% by weight of polymerizable unsaturated acid group containing monomer based on the superabsorbent polymer, and from about 0.001 to about 5% by weight of an internal crosslinking agent based on the polymerizable unsaturated acid group containing monomer, and wherein the superabsorbent polymer has a degree of neutralization of greater than about 25%; b) preparing superabsorbent polymer particles from the superabsorbent polymer; c) treating the superabsorbent polymer particles with surface additives including: i) from about 0.001 to about 5% by weight of surface crosslinking agent based on the dry superabsorbent polymer composition; ii) from about 0.01 to about 10% by weight of a penetration modifier based on the dry superabsorbent polymer composition; iii) from about 0.01 to about 5% by weight of an insoluble, inorganic powder based on the dry superabsorbent polymer composition; and iv) from about 0.01 to 1% by weight of a thermoplastic polymer based on the dry superabsorbent polymer composition is applied on the particle surface, and wherein the thermoplastic polymer surface treated superabsorbent polymer particles are heat treated wherein the thermoplastic polymer of iv) is applied to the superabsorbent polymer particles prior to the heat treatment; and d) heat treating the coated superabsorbent polymer particle to form heat treated coated superabsorbent polymer particle; and e) treating the heat treated coated superabsorbent polymer particle with from about 0.01 to 5% by weight of a cationic polymer selected from poly(vinyl amines), poly(allylamines), poly(ethylene imine), poly(amino propanol vinyl ethers), poly(acrylamidopropyl trimethyl ammonium chloride), poly(diallyldimethyl ammonium chloride), partially deacetylated chitin, chitosan, polyasparagins, polylysines, polyglutamines, polyarginines, including salts thereof; wherein the superabsorbent polymer composition has the characteristics of centrifuge retention capacity as measured by the Centrifuge Retention Capacity Test of at least about 23 g/g; a free swell gel bed permeability as measured by the Free Swell Gel Bed Permeability Test of at least about 100 Darcy.