Patent ID: 8367774

Claim:
A process for producing an agglomerated superabsorbent polymer particle comprising less than about 10 wt. %, based on the total weight of the agglomerated superabsorbent polymer particle, of superabsorbent polymer fine particles having a particle size of less than about 150 μm, said process steps comprising: (A) supplying (i) post crosslinked superabsorbent polymer fine particles having at least about 40 wt. %, based on the total weight of the agglomerated superabsorbent polymer particle, a particle size of less than about 150 μm (B) spraying or mixing the post crosslinked superabsorbent polymer fine particles of (A) with a fluid comprising a) more than about 18 wt. % to about 55 wt %, based on the total weight of the fluid, of a cross-linkable, uncross-linked polyacrylate solution neutralized to from about 45 mol % to about 55 mole %, which polyacrylate solution is based on polymerized, polyacrylic acid or salts thereof to at least about 20 wt. %, based on the total weight of the cross-linkable, uncrosslinked polymer, and b) a crosslinker; (C) heating the post crosslinked superabsorbent polymer fine particles brought into contact with the fluid of step (B) to a temperature within a range from about 100 to about 200° C., so that the cross-linkable, uncross-linked polymer at least partially crosslinks to form agglomerated superabsorbent polymer particles having a particle size of more than about 850 μm; and (D) comminuting the agglomerated superabsorbent polymer particles of step (C) to produce at least about 80 wt. % of the agglomerated superabsorbent polymer particles of step (C) to have a particle size within the range of about 200 μm to about 900 μm; wherein (a) the cross-linkable, uncross-linked polyacrylate solution comprises, besides the polymerized, ethylenically unsaturated, acid groups-bearing monomers, further polymerized, ethylenically unsaturated monomers (M) capable of reacting with polymerized acid group-bearing monomers in a condensation reaction, in an addition reaction, or in a ring opening reaction, and (b) wherein the agglomerated superabsorbent polymer particle has less than about 10 wt. %, based on the total weight of the agglomerated superabsorbent polymer particle, of superabsorbent polymer fine particle size of less than about 150 μm.