Abstract: A process for classifying water-absorbing polymer beads, wherein screens having different mesh sizes are used before and after the postcrosslinking to remove the oversize.

Abstract: The invention relates to processes for preparing water absorbing polymers by polymerization of a monomer solution comprising allyl acrylate and/or allyl alcohol, the solution comprising not more than 0.002% by weight of allyl acrylate and/or allyl alcohol, based on acrylic acid, to aqueous monomer solutions for producing water absorbing polymers, to water absorbing polymers, to processes for producing hygiene articles and also to hygiene articles.

Abstract: A process for producing water-absorbing polymer particles by polymerizing droplets of a monomer solution in a gas phase surrounding the droplets and postcrosslinking the polymer particles, wherein the postcrosslinked polymer particles are at least partly coated.

Abstract: A process for producing water-absorbing polymer particles, wherein the water-absorbing polymer particles are surface postcrosslinked with unsaturated fatty acids or derivatives thereof.

Abstract: A process for thermally surface postcrosslinking water-absorbing polymer particles in a fluidized bed generated by means of a carrier gas, wherein the surface postcrosslinker is supplied to the fluidized bed in gaseous form.

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 process for producing water-absorbing polymer particles by polymerizing droplets of a monomer solution in a surrounding gas phase, wherein the monomer solution comprises at least 0.0002% by weight of oxygen and the oxygen content of the gas phase is at least 0.5% by volume.

Abstract: The present invention relates to novel hydrophilic swellable addition polymers comprising improved odor control, a process for their preparation and their use for absorbing aqueous fluids and a process for screening superabsorbents.

Abstract: The present invention relates to a process for producing water-absorbent polymer particles by polymerizing droplets of a monomer solution in a surrounding heated gas phase and flowing the gas cocurrent through the polymerization chamber, wherein the temperature of the gas leaving the polymerization chamber is 130° C. or less, the gas velocity inside the polymerization chamber is at least 0.5 m/s, and the droplets are generated by using a droplet plate having a multitude of bores.

Abstract: Water-absorbing polymeric particles are produced by polymerizing a monomer solution or suspension comprising at least one unsaturated carboxylic acid, at least one hydroquinone monoether and at least one inorganic peroxide and coating the polymeric particles with at least one basic salt of a bivalent metal cation.

Abstract: The invention relates to a process for producing a water-absorbing resin by polymerization of a reaction mixture comprising at least one hydrophilic monomer and, if appropriate, at least one crosslinker in a reactor, which comprises admixing the reaction mixture with at least one first portion of a particulate additive before the reaction mixture has reached a residence time of 40% of the overall residence time in the reactor and with at least one second portion of a particulate additive when the reaction mixture has reached a residence time of 45% or more of the overall residence time in the reactor, the additive being selected from water-absorbing resin powders, fillers and mixtures thereof, the total solids content of monomer and additive being in the range from 30% to 60% by weight, the amount of additive being in the range from 5% to 50% by weight, based on the monomers, and the weight ratio of the first portion to the second portion of the additive being in the range from 10:1 to 1:5.

Abstract: A process for producing water-absorbing polymer particles by polymerizing droplets of a monomer solution in a gas phase surrounding the droplets, wherein the particle surface is coated at least partly with at least one polymer and/or wax.

Abstract: Surface-crosslinked superabsorbents are produced using a process that comprises the steps of contacting a superabsorbent base polymer with a polyvalent metal salt solution produced by dissolving at least two different polyvalent metal salts, at least one of which comprises a chelate-forming anion, and heat-treating to produce a surface-crosslinked superabsorbent.

Abstract: The present invention relates to novel hydrophilic swellable addition polymers comprising improved odor control, a process for their preparation and their use for absorbing aqueous fluids and a process for screening superabsorbents.

Abstract: The invention relates to a process for producing a water-absorbing resin by polymerization of a reaction mixture comprising at least one hydrophilic monomer and, if appropriate, at least one crosslinker in a reactor, which comprises admixing the reaction mixture with at least one first portion of a particulate additive before the reaction mixture has reached a residence time of 40% of the overall residence time in the reactor and with at least one second portion of a particulate additive when the reaction mixture has reached a residence time of 45% or more of the overall residence time in the reactor, the additive being selected from water-absorbing resin powders, fillers and mixtures thereof, the total solids content of monomer and additive being in the range from 30% to 60% by weight, the amount of additive being in the range from 5% to 50% by weight, based on the monomers, and the weight ratio of the first portion to the second portion of the additive being in the range from 10:1 to 1:5.

Abstract: A process for producing water-absorbing polymeric particles by dropletization polymerization in the gas phase, which comprises drying the polymeric particles after the polymerization in a fluidized bed, the water-absorbing polymeric particles themselves, hygiene articles comprising these water-absorbing polymeric particles and also apparatus for implementing the process.

Abstract: The present invention relates to a process for postcrosslinking water-absorbing polymeric particles in the absence of oxidizing gases, to the water-absorbing polymers preparable by the process and to their use in hygiene articles and packaging materials.

Abstract: A process for preparing water-absorbing polymer beads with high permeability by polymerizing droplets of a monomer solution in a gas phase surrounding the droplets, wherein the monomer solution comprises at least 0.5% by weight of a crosslinker, based on the monomer, the polymerization in the droplet takes place in homogeneous phase, and the polymer beads have a mean diameter of at least 150 ?m.

Abstract: Water-absorbing polymeric particles are produced by polymerizing a monomer solution or suspension comprising at least one unsaturated carboxylic acid and at least one hydroquinone monoether, and coating the polymeric particles with at least one salt of a tervalent metal cation of a carboxylic acid and/or at least one basic salt of a tervalent metal cation.

Abstract: A process for producing water-absorbing polymer particles by polymerizing droplets of a monomer solution in a gas phase surrounding the droplets and postcrosslinking the polymer particles, wherein the postcrosslinked polymer particles are at least partly coated.