Abstract: A process for producing water-absorbing polymer particles with high free swell rate and high permeability by polymerization of an aqueous monomer solution or suspension to give an aqueous polymer gel, wherein a thermal blowing agent essentially free of inorganic acid anions is mixed into the polymer gel, and subsequent thermal drying of the polymer gel.

Abstract: A process for preparing water-absorbing polymer particles, comprising polymerization of a foamed monomer solution or suspension, drying, grinding and classification.

Abstract: A process for preparing water-absorbing polymer beads with high permeability by polymerizing droplets of a monomer solution, comprising monomers bearing acid groups, in a gas phase surrounding the droplets, wherein the monomer solution comprises polyvalent cations and the polymer beads have a mean diameter of at least 150 ?m.

Abstract: A process for classifying water-absorbing polymer particles, wherein screens having different mesh sizes are used before and after surface postcrosslinking to remove the undersize (fines).

Abstract: The invention relates to the production of superabsorbent polymers comprising conveying a polymer gel having acid groups on an oscillating conveyor belt to a continuous through-circulation belt dryer, wherein the belt speed of the conveyor belt is at least 0.4 m/s.

Abstract: The invention relates to a process for producing water-absorbing polymer particles, comprising polymerization, drying the resulting polymer gel on a through circulation belt dryer, crushing the dried polymer gel, pre-grinding, separating of incompletely dried particles with a perforated plate, grinding and classifying the resulting polymer particles.

Abstract: The present invention relates to a process for producing fluid-absorbent cores, comprising mixing a fibrous material and fluid-absorbent polymer particles having low moisture content and low apparent density and pressing the obtained mixture under specific conditions.

Abstract: The invention relates to a process for producing water-absorbing polymer particles, comprising the steps of: —processing an aqueous polymer gel from polymerization of a monomer solution or suspension, —drying the aqueous polymer gel in a conveyer dryer, in particular in a forced air conveyer dryer, wherein —the conveyer dryer has a circulating conveyer belt and the aqueous polymer gel is conveyed on the circulating conveyer belt, and wherein —the circulating conveyer belt is formed as a circulating plate conveyer belt, comprising a number of belt plates separated by a hinge line of a hinge assembly and each belt plate having a surface for receiving the aqueous polymer gel, wherein said hinge assembly comprises a knuckle joint (301) with the hinge line in form of a straight hinge line.

Abstract: The invention relates to a process for producing water-absorbing polymer particles, comprising polymerization and drying the resulting polymer gel on a through-circulation belt dryer having at the end of the belt in transport direction a means for guiding the dried polymer gel down towards a means for crushing the dried polymer gel.

Abstract: A process for producing water-absorbing polymer particles, wherein surface postcrosslinked water-absorbing polymer particles are remoisturized and classified, and wherein the time between remoisturization and classification is at least 15 minutes.

Abstract: A process for continuously preparing water-absorbing polymer beads, comprising the drying of a polymer gel on a forced-air belt dryer, the water content of the polymer gel being used to control the forced-air belt dryer during or after the drying.

Abstract: The use of water-absorbing polymer particles for dewatering feces, the water-absorbing polymer particles being obtainable by polymerizing a foamed monomer solution or suspension, drying the polymeric foam and grinding the dried foam.

Abstract: A process for classifying water-absorbing polymer particles, wherein screens having different mesh sizes are used before and after surface postcrosslinking to remove the undersize (fines).

Abstract: An apparatus for producing a water-absorbing polymer by polymerizing a monomer solution and drying the resulting hydrogel by means of a heated gas stream through effecting the drying in two or more temperature zones. A gas stream is flowed against the hydrogel upwardly in the upstream sector of the belt dryer and downwardly in the downstream sector of the belt dryer, the direction of flow being reversed at a water content of 15% to 45% by weight for the hydrogel. The hydrogel layer is flowed against in a belt dryer upwardly to some extent at least, the gas velocity being 5% to 30% of the gas velocity required to lift the hydrogel off the belt, to produce hygiene articles.

Abstract: A process for producing water-absorbing polymer particles with high free swell rate and high permeability by polymerization of an aqueous monomer solution or suspension to give an aqueous polymer gel, wherein a thermal blowing agent essentially free of inorganic acid anions is mixed into the polymer gel, and subsequent thermal drying of the polymer gel.

Abstract: A process for producing water-absorbing polymer particles having high free swell rate and high centrifuge retention capacity with simultaneously high permeability of the swollen gel bed by polymerization of an aqueous monomer solution in a polymerization reactor having at least two shafts (kneaders) which rotate in an axially parallel manner, subsequent extrusion at high temperatures and thermal surface postcrosslinking.

Abstract: The invention relates to a process for producing water-absorbing polymer particles, comprising polymerization and drying the resulting polymer gel on a through-circulation belt dryer having at the end of the belt in transport direction a means for guiding the dried polymer gel down towards a means for crushing the dried polymer gel.

Abstract: A process for preparing water-absorbing polymeric foams by polymerization of a foamed aqueous monomer solution or suspension, comprising an ethylenically unsaturated monomer which bears acid groups and may be at least partly neutralized, a crosslinker, a photoinitiator and a surfactant.

Abstract: A process for producing water-absorbing polymer particles by polymerizing droplets of a monomer solution in a surrounding gas phase in a reaction chamber, wherein the monomer solution is metered into the reaction chamber via at least one bore, and the diameter is from 210 to 290 ?m per bore and the metering rate is from 0.9 to 5 kg/h per bore.

Abstract: A feminine hygiene absorbent article comprising water-absorbing polymer particles, obtainable by polymerization of a foamed monomer solution or suspension, drying, grinding and classification.