Patent application number | Description | Published |
20080200623 | Polymerization Process - The invention relates to a process for preparing water-absorbing polymer particles, comprising the inertization of monomer solutions, wherein the monomer solution, based on the dissolved monomer, comprises from 0.001 to 0.016% by weight of at least one polymerization inhibitor and at least 50% by volume of the inert gas used to inertize the monomer solution is transferred into the polymerization reactor together with the inertized monomer solution, and also to apparatus for performing the process. | 08-21-2008 |
20080202987 | Method for Grading a Particulate Water-Absorbing Resin - Process for classifying a particulate water-absorbing resin using a sieving apparatus at a reduced pressure compared with the ambient pressure and a sieving apparatus for classifying a particulate water-absorbing resin at a reduced pressure compared with the ambient pressure. | 08-28-2008 |
20080214749 | Method for the Production of Water Absorbing Polymers - A process for producing a water-absorbing polymer by polymerizing a monomer solution and drying the resulting hydrogel by means of a heated gas stream comprises
| 09-04-2008 |
20080221282 | Polymerization Process - The invention relates to a process for continuously preparing water-absorbing polymer particles by mixing a monomer solution with a redox initiator consisting of at least one oxidizing agent and at least one reducing agent and polymerizing it, wherein the monomer solution is mixed with at least one oxidizing agent upstream of the polymerization reactor and the at least one reducing agent is metered into the polymerization reactor, and also to an apparatus for performing the process. | 09-11-2008 |
20080227933 | Method For Producing Water-Absorbing Polymers - The invention relates to a process for preparing water-absorbing polymers by polymerizing a monomer solution, wherein the oxygen content of the monomer solution has been reduced by addition of at least one reducing agent before the polymerization. | 09-18-2008 |
20080242816 | Neutralization Process - The invention relates to a neutralization process in which at least one ethylenically unsaturated carboxylic acid is neutralized at least partly with a base and at least one stream of the neutralization is determined continuously, and also to an apparatus for carrying out the process. | 10-02-2008 |
20080275195 | Polymerization Process - The present invention relates to a process for continuously preparing water-absorbing polymers by mixing a monomer solution with at least one crosslinker and polymerizing the resulting mixture, wherein the residence time of the mixture between the addition of the at least one crosslinker and the entry into the polymerization reactor is less than 180 seconds, and also to an apparatus for performing the process. | 11-06-2008 |
20080306209 | Production of a Water-Absorbing Resin to Which a Particulate Additive is Admixed - 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. The resin powder is recycled fine-sized material for example. Not only the residual monomer content, specifically the residual crosslinker content, but also the level of extractables in the water-absorbing resin are reduced by the method of addition described. A high fraction of additives can be incorporated without the properties of the water-absorbing resin obtained being adversely affected. The additives enter a sufficiently firm bond with the resin, so that no excessive dusting occurs on exposure to mechanical stress. | 12-11-2008 |
20090192035 | Method for Producing Water-Absorbent Polymer Particles with a Higher Permeability by Polymerising Droplets of a Monomer Solution - 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 a water-insoluble inorganic salt is suspended in the monomer solution and the polymer beads have a mean diameter of at least 150 μm. | 07-30-2009 |
20090192036 | Method for the Production of Water Absorbent Polymer Particles by Polymerizing Drops of a Monomer Solution - The invention relates to a method for the production of water absorbent polymer particles by polymerizing drops, comprising at least one monomer in a gas phase surrounding the drops, wherein the drops are produced by surrounding a first monomer solution with a second monomer solution and polymerizing the second monomer solution to a higher cross-linked polymer than the first monomer solution. | 07-30-2009 |
20090194462 | Method for Grading Water-Absorbent Polymer Particles - 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. | 08-06-2009 |
20090221746 | Neutralization Process - The invention relates to a neutralization process in which at least one ethylenically unsaturated carboxylic acid is preneutralized at least partly with a base, wherein the preneutralized solution is divided into at least two part-solutions and at least one part-solution is aftertreated so as to form part-solutions with different degree of neutralization and/or solids content, and also to an apparatus for carrying out the process. | 09-03-2009 |
20090239071 | Method for Producing Water-Absorbent Polymer Particles with a Higher Permeability by Polymerising Droplets of a Monomer Solution - 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 μm. | 09-24-2009 |
20090258994 | Method for Producing Post-Cured Water-Absorbent Polymer Particles with a Higher Absorption by Polymerising Droplets of a Monomer Solution - A process for preparing postcrosslinked water-absorbing polymer beads with high absorption by polymerizing droplets of a monomer solution in a gas phase surrounding the droplets, wherein the solids content of the monomer solution is at least 35% by weight and the polymer beads have a mean diameter of at least 150 μm. | 10-15-2009 |
20090261023 | Method for the Classification of Water Absorbent Polymer Particles - A process for continuously classifying water-absorbing polymer beads by means of at least one screen, at least one screen having at least one guide device on the screen surface. | 10-22-2009 |
20100189994 | AQUEOUS DISPERSIONS OF CROSS-LINKED, TERTIARY ESTER GROUPS CONTAINING EMULSION POLYMERISATES AND WATER-ABSORBENT MATERIALS ON A CARRIER MATERIAL MADE THEREOF - Aqueous dispersions of crosslinked emulsion polymers comprising tertiary ester groups, comprising
| 07-29-2010 |
20120296297 | FEMININE HYGIENE ABSORBENT ARTICLES COMPRISING WATER-ABSORBING POLYMERIC FOAMS - A feminine hygiene absorbent article comprising water-absorbing polymeric foams obtainable 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. | 11-22-2012 |
20120296298 | FEMININE HYGIENE ABSORBENT ARTICLES COMPRISING WATER-ABSORBING POLYMER PARTICLES - A feminine hygiene absorbent article comprising water-absorbing polymer particles, obtainable by polymerization of a foamed monomer solution or suspension, drying, grinding and classification. | 11-22-2012 |