Patent ID: 8309682

Claim:
A superabsorbent polymer particulate composition made by the process of including recycled superabsorbent polymer fines: a) treating the superabsorbent polymer fines with a caustic solution containing from about 0.1 to about 12% caustic based on the weight of the superabsorbent polymer fines to form caustic treated superabsorbent polymer fines; b) mixing the caustic treated superabsorbent polymer fines obtained in step a) with a polymerization solution containing at least one cross linking agent and a partially neutralized monomer in which the content of the caustic treated superabsorbent polymer fines relative to the total amount of the monomer is from about 0.1 to about 30 wt %; c) polymerizing the mixture obtained in step b) to produce the superabsorbent polymer gel; d) comminuting the superabsorbent polymer gel of step c) to form superabsorbent polymer particulate; and e) coating the superabsorbent polymer particulate of step d) with a surface crosslinking agent and surface additives, heating said coated polymer, separating said dried superabsorbent polymer particulate into a portion having a desired particle size from about 150 μm to about 850 μm as measured by screening through a U.S. standard 20 mesh screen and retained on a U.S. standard 100 mesh screen, wherein at least about 40% by weight of the superabsorbent polymer particulate has a particle size from about 300 μm to about 600 μm as measured by screening through a U.S. standard 30 mesh screen and retained on a U.S. standard 50 mesh screen wherein the superabsorbent polymer particulate composition made by the process as set forth in steps a) to e) above have values of an absorption under load at 0.9 psi and free swell gel bed permeability greater than the values of an absorption under load at 0.9 psi and free swell gel bed permeability of the superabsorbent polymer particulate composition made by the process of including recycled superabsorbent polymer fines wherein the recycled superabsorbent polymer fines are not treated with caustic solution containing from about 0.1 to about 12% caustic based on the weight of the superabsorbent polymer fines.