Method for producing water-absorbing polymer particles with high swelling rate and high centrifuge retention capacity with simultaneously high permeability of the swollen gel bed

• Main Authors: Weismantel Matthias, Gieger Thomas, Klock Volker, Haag Monica, Krauss Roland
• Format: Patent
• Language: English
• Published: 21.11.2017
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS, ORSURGICAL ARTICLES; CHEMISTRY; COMPOSITIONS BASED THEREON; DISINFECTION, STERILISATION, OR DEODORISATION OF AIR; GENERAL PROCESSES OF COMPOUNDING; HUMAN NECESSITIES; HYGIENE; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS, OR SURGICALARTICLES; MEDICAL OR VETERINARY SCIENCE; METALLURGY; METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS INGENERAL; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; WORKING-UP

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.