Water-absorbing polymers with improved properties, process for the preparation and use thereof

Abstract

The present invention relates to powdery absorbents for water and aqueous liquids, which are based on water-swellable, but not water-soluble, polymers, are cross-linked, and are built up of partially neutralized, monoethylenically unsaturated, acid groups-containing monomers, optional further monomers copolymerizable with these, and optional polymers suitable as a graft basis. These polymers are produced by using a cross-linker combination consisting of CH.sub.2 .dbd.CR.sup.5 --CO--(OCHR.sup.3 --CHR.sup.3).sub.z O--CH.sub.2 --CR.sup.5 .dbd.CH.sub.2 I. R.sup.1 --[O(CHR.sup.3 --CHR.sup.3 O).sub.u --CO--R.sup.2 ].sub.x II. with R.sup.1 : multivalent C.sub.2-10 -alkyl, R.sup.2 : linear or branched C.sub.2-10 -alkenyl, R.sup.3 : H, CH.sub.3, C.sub.2 H.sub.5, R.sup.5 : H, CH.sub.3, x: 2-6, u: 0-15, z: 3-20 and a secondary cross-linker. Superficial secondary cross-linkage achieves a property combination of high retention, high absorption under pressure, low soluble contents, and a rapid liquid absorption. The polymers are used in constructions, such as diapers, for the absorption of body fluids, in current-conducting or light-transmitting cables, and in the cultivation of plants.

Dependencies are inferred from the claim text.