Method for producing water-absorbing polymer particles

• Main Authors: HAAG MONIKA, KRAUSS ROLAND, BRAUN MARKUS ALBERT, DEUERLEIN STEPHAN, KLOCK VOLKER
• Format: Patent
• Language: Chinese; English
• Published: 18.08.2017
• 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

The invention relates to a method for producing water-absorbing polymer particles, having the following steps: a) a polymerization step in which an aqueous monomer solution comprising at least one ethylenically unsaturated acid group-carrying monomer (M) that can be at least partly neutralized and at least one crosslinking agent is polymerized, an aqueous polymer gel being obtained; b) a granulation step in which the aqueous polymer gel with a solid content of 35 to 70 wt.% and a temperature between 75 and 125 DEG C is pressed out of a high-pressures zone into a low-pressure zone through a perforated plate and a granulate is obtained, the pressure difference between the high-pressure zone and the low-pressure zone equaling 4 to less than 14 bar and the opening ratio of the perforation plate equaling 30 to 80%; c) a drying step in which the granulate is dried to a moisture content of less than 10 wt.%; d) a grinding step and a classifying step, wherein water-absorbing polymer particles are obtained; and e) a s