Evonik Corporation

Evonik Stockhausen Gmbh

Evonik Superabsorber Gmbh

Michael M Azad

Mark Joy

Scott J Smith

Scott Smith

Markus Frank

Whei-Neen Hsu

Geoffrey Wyatt Blake

Michael S Jarman

Gonglu Tian

Bernfried A Messner

Laurent Wattebled

David L Bergman

Frank Loeker

Christoph Loick

Matthew Thomas Ondisco

Anne Ix-Mund

Nicolaas De Bruin

Regina Gilmer

Geoffrey W Blake

Rani Wieand

Ron Wiedbusch

Andrew J Lang

The present invention relates to an anti-stick processing aid for use in a process for producing water-absorbing polymers, comprising the steps of: i) mixing (&#x3b1;1) 0.1 to 99.999% by weight of polymerizable, ethylenically unsaturated monomers containing acid groups, or salts thereof, (&#x3b1;2) 0 to 70% by weight of monomers copolymerizable with (&#x3b1;1), (&#x3b1;3) 0.001 to 10% by weight of crosslinkers, (&#x3b1;4) 0 to 30% by weight of polymers, (&#x3b1;5) 0 to 80% by weight of water, and (&#x3b1;6) 0 to 20% by weight of assistants, (ii) free-radical polymerization with crosslinking to form a hydrogel polymer, (iii) drying the hydrogel polymer, (iv) grinding and sieving the hydrogel polymer, (v) surface postcrosslinking the hydrogel polymer and (vi) drying and finishing the water-absorbing polymer,wherein the anti-stick processing aid is used before and/or in steps (iii).

Anti-stick processing aids and use thereof in the production of water-absorbing particles

The present invention relates to a fast particulate superabsorbent polymer composition comprising a polymer comprising a neutralized aluminum salt solution applied to the surface of a particulate superabsorbent polymer; wherein an aqueous solution of the neutralized aluminum salt has a pH value from about 5.5 to about 8; and subsequent to subjecting the particulate superabsorbent polymer composition to the Processing Test, the particulate superabsorbent polymer composition has a permeability stability index of from about 0.60 to about 0.99, and a compressibility from 1.30 mm/N to about 4 mm/N as measured by the Compression Test, and wherein the particulate superabsorbent polymer composition may have a Vortex time of from 25 to 60 seconds and absorbency under load at 0.9 psi of from 15 to 21 g/g.

Particulate superabsorbent polymer composition having improved stability and fast absorption

A process for the preparation of superabsorbent polymer containing clay, the process including the steps of (I) polymerizing a polymerization mixture comprising: (a) one or more ethylenically unsaturated carboxyl-containing monomers, (b) one or more crosslinking agents, (c) optionally one or more comonomers copolymerizable with the carboxyl-containing monomer, (d) neutralizing agent to partially neutralize the polymer to from about 50% to about 99%, by weight, and (e) a polymerization medium, to form a crosslinked partially neutralized hydrogel, (II) admixing a clay with the crosslinked partially neutralized hydrogel to form partially neutralized superabsorbent polymer-clay hydrogel; (III) drying the crosslinked partially neutralized hydrogel at a temperature from about 190&#xb0; C. to about 210&#xb0; C. and for a time period of from about 15 minutes to about 120 minutes, and (IV) comminuting the dried partially neutralized superabsorbent polymer-clay hydrogel to particles.

Superabsorbent polymer containing clay particulate, and method of making same

The invention relates to absorptive, crosslinked polymers which are based on partly neutralized, monoethylenically unsaturated monomers carrying acid groups, and have improved properties, in particular in respect of their capacity for transportation of liquids in the swollen state, and which has a high gel bed permeability and high centrifuge retention capacity.

Superabsorbent polymer with high permeability

Superabsorbent polymer containing clay, particulate, and method of making same

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Reidsville, NC, United States of America

Michael M Azad