WO1999055767A1 - Mechanically stable hydrogels - Google Patents
Mechanically stable hydrogels Download PDFInfo
- Publication number
- WO1999055767A1 WO1999055767A1 PCT/EP1999/002702 EP9902702W WO9955767A1 WO 1999055767 A1 WO1999055767 A1 WO 1999055767A1 EP 9902702 W EP9902702 W EP 9902702W WO 9955767 A1 WO9955767 A1 WO 9955767A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- hydrogel
- ionically crosslinked
- hydrogels according
- crosslinked hydrogels
- gel
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J3/00—Processes of treating or compounding macromolecular substances
- C08J3/24—Crosslinking, e.g. vulcanising, of macromolecules
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
- A61L15/16—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons
- A61L15/42—Use of materials characterised by their function or physical properties
- A61L15/60—Liquid-swellable gel-forming materials, e.g. super-absorbents
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F8/00—Chemical modification by after-treatment
- C08F8/44—Preparation of metal salts or ammonium salts
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
- A61F13/00—Bandages or dressings; Absorbent pads
- A61F13/15—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators
- A61F13/53—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the absorbing medium
- A61F2013/530481—Absorbent pads, e.g. sanitary towels, swabs or tampons for external or internal application to the body; Supporting or fastening means therefor; Tampon applicators characterised by the absorbing medium having superabsorbent materials, i.e. highly absorbent polymer gel materials
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2300/00—Characterised by the use of unspecified polymers
- C08J2300/14—Water soluble or water swellable polymers, e.g. aqueous gels
Definitions
- the present invention relates to ionically crosslinked hydrogels, obtainable by adding aluminates of the formula (I)
- M is potassium or sodium and n is an integer from 1 to 10,
- water-insoluble, crosslinked polymers containing carboxyl groups which are capable of swelling and forming hydrogels in aqueous liquids and body fluids, such as e.g. Take up urine or blood and retain the amount of fluid absorbed under a certain pressure.
- Substances are preferably used which contain two or more groups which can form covalent bonds with the carboxyl groups of the hydrophilic polymers (EP-A-0 349 240).
- Polyglycidyl ethers, haloepoxy compounds, polyols, polyamines or polyisocyanates can be used as crosslinking agents.
- DE-A-3 314 019, EP-A-0 317 106 and DE-A-3 737 196 describe polyfunctional azidine compounds, 2
- EP-A-372 981, JP-A-03 179 008, US-A-5 314 420 and US-A-4 690 971 describe the use of polyvalent metal ions in general for surface crosslinking.
- the invention thus relates to ionically crosslinked hydrogels, obtainable by adding aluminates of the formula (I)
- M is potassium or sodium and n is an integer from 1 to 10,
- the ionic crosslinking by means of aluminate ions takes place homogeneously in the gel form of the polymeric hydrogels before drying to form powders or granules.
- hydrogel structures are produced by adding aluminumates I, preferably [Al (OH) 4 ] " , to polymers containing carboxyl groups and / or alkali metal or ammonium carboxylate groups, aqueous gels, so-called hydrogels, which can be uncrosslinked or pre-crosslinked by covalent bonds.
- AI (OH) 3 dissolves as an amphoteric hydroxide both in acid
- the Alumination [AI (OH) 4 ] is not stable and condenses easily to higher molecular weight oxo compounds under water. Instead of condensation, the Alumination [AKOH 4 )] - like the isolation of sodium salts of the composition 3 Na 2 0 -Al 2 ⁇ 3 -6H 2 0 shows can also be stabilized by taking up 2 OH ions
- K 2 [H 6 A1 2 0 7 ] K 2 0 • A1 2 0 3 • 3 H 2 0
- covalently crosslinked hydrogels which are obtained by polymerizing 90-99.99 mol% of a monounsaturated monomer containing carboxyl groups and / or alkali metal or ammonium carboxylate groups and 0.01-10 mol% of a crosslinking agent.
- Suitable crosslinkers are in particular methylenebisacryl or methacrylamide, esters of unsaturated mono- or polycarboxylic acids of polyols, such as diacrylate or triacrylate, e.g. Butanediol or ethylene glycol diacrylate or methacrylate as well as triethylolpropane triacrylate and allyl compounds such as allyl (meth) acrylate, tri-allylcyanurate, maleic acid diallyl ester, polyallyl ester, tetraallyloxyethane, triallylamine, tetraallyl ethylene diphosphate such as phosphate and allyl ester diamine, for example allyl esters, A-0 343 427.
- esters of unsaturated mono- or polycarboxylic acids of polyols such as diacrylate or triacrylate, e.g. Butanediol or ethylene glycol diacrylate or methacrylate as well as triethyl
- hydrogels which are prepared using polyallyl ethers as crosslinking agents and by acidic homopolymerization of acrylic acid are particularly preferred.
- Suitable crosslinkers are pentaerythritol tri- and tetraallyl ether, polyethylene glycol diallyl ether, monoethylene glycol diallyl ether, glycerol di- and tri-allyl ether, polyallyl ether based on sorbitol, and alkoxylated variants thereof.
- Monounsaturated monomers are, for example, vinyl acetic acid and preferably acrylic acid and methacrylic acid and their alkali metal or ammonium salts, e.g. Sodium, potassium and ammonium acrylates. Preference is given to ionically crosslinked hydrogel structures which are composed of 50 to 99.99% by weight of structural units which are derived from acrylic acid.
- Such hydrogels are generally known and are produced by conventional processes.
- the ionically crosslinked hydrogel structures according to the invention are preferably obtained by free-radically polymerizing aqueous acrylic acid solutions with the addition of polyolefinically unsaturated compounds, for example the above-mentioned crosslinking agents.
- the polymerization process gives water-containing hydrogels, which are then added to pH values between 3.0 and 9.5, preferably between 4.0 and 7.5, by adding illuminations as described above in connection with bases such as sodium or potassium hydroxide. 5 places.
- the bases can be added either before the addition of the aluminate or together with the aluminate. In the former case, neutralized or partially neutralized gels are crosslinked. It is also possible to polymerize partially neutralized aqueous acrylic acid solutions, preferably in the presence of a crosslinking agent, and then to crosslink them with aluminates, if appropriate with the addition of a base.
- the amount of aluminates used is 0.05 to 80 mol%, preferably 0.05 to 30 mol% of aluminum, based on the sum of carboxyl groups and alkali metal or ammonium carboxylate groups, preferably based on the acid units to be neutralized in the hydrogel.
- the polymerization can be triggered by radical formers, such as organic or inorganic peroxides and azo compounds.
- radical formers such as organic or inorganic peroxides and azo compounds. Examples are benzoyl peroxide, tert. -Butyl hydroperoxide, cumene hydroperoxide, (H) 2 S 2 08, K 2 S 2 0 ⁇ , H 2 S 2 0 8 , H 2 0 2 or azodiisobutyronitrile.
- Redox systems are also outstandingly suitable as polymerization initiators.
- the polymerization can also be triggered by high-energy radiation.
- compounds of the general formula I are first added to an uncrosslinked pre (co) polymer, this is usually done before drying by homogeneous mixing, for example by kneading an aqueous polymer gel in a kneader.
- the gel particles are subjected to a drying process to remove the water. 6, then grind and set a desired particle size distribution by sieving.
- the polymer particles produced in this way are able to absorb many times their own weight in aqueous liquids.
- Hydrogel particles are formed, which are characterized by special physical properties.
- hydrogel particles which have been produced in a similar way by polymerizing unsaturated water-soluble acids with the addition of polyolefinically unsaturated compounds, are subjected to repeated mechanical stress, such as exposure to strong shear forces, irreversible degradation of the hydrogel network structure takes place through the destruction of covalent bonds under mechanical stress. This has the result that the mechanical stability of the gel particles that is, the so-called gel ⁇ strength drastically decreases.
- hydrogel structures according to the invention which in addition to covalent crosslinking elements are crosslinked according to an ionic mechanism, do not show this disadvantage since the ionic crosslinking elements are capable of recombination.
- hydrogels according to the invention are outstandingly suitable as absorbents for aqueous liquids, for the formulation of cosmetic preparations, as consolidators and / or binders of fibrous sheet-like structures containing reactive groups, and as drilling fluids and cement sludge in the production of petroleum.
- Hydrogels according to the invention based on acrylic acid are particularly suitable for use as so-called “super absorbing polymers” (SAP) for the use of hygiene articles, for example diapers, tampons or sanitary napkins. These preferably contain 50 to 99.99, in particular up to 98% by weight of structural units which are derived from acrylic acid. Particularly preferred are hydrogels, which are copolymers of acrylic acid and di- or polyunsaturated compounds, which have been prepared in aqueous solution.
- Hydrogels according to the invention based on carboxymethyl polysaccharides are also outstandingly suitable for use as SAP.
- hydrogels In addition to high absorption capacity, hydrogels also have high gel strength.
- the improved mechanical property profile of the hydrogel structures according to the invention compared to conventional covalently crosslinked products can be shown by measuring the gel recovery index.
- the gel recovery index is measured using a Creep Meter, model RE-3305 from Yamaden Co., Ltd.
- This device is a penetrometer, which can be used to carry out investigations of changes in structure and consistency over time or due to changing load factors.
- the centerpiece of the device is a measuring slide that can be moved in the vertical direction with a force transducer and a stamp as a test specimen.
- the force transducer measures the compressive or tensile forces that act on the test specimen when the slide is moved from the sample.
- the maximum penetration depth of the test specimen when measuring the force
- the maximum force absorption when measuring the penetration depth
- the depth of penetration of the star apex is selected so that the force absorption in the 20th cycle (50 "3%) is the force absorption in the 1st cycle, and must therefore be individually determined for each product through preliminary tests. 8 be averaged.
- the gel is left on the sample plate for 20 minutes at room temperature. During this time, the gel has the opportunity to recover and repair the network defects caused by the mechanical stress. After this time the test program is repeated (2nd cycle series), the depth of penetration of the stamp remains unchanged.
- Tables 1 and 2 show the force absorption data for gels that do not have a repair effect or a complete repair effect to clarify the test method.
- the 0 gel recovery index is calculated as follows:
- a redox system consisting of 2.2 g 2, 2 '-azobisamidinopropane dihydrochloride, dissolved in 20 g demineralized water, 4 g potassium peroxodisulfate, dissolved in 150 g demineralized water and 0 , 4 g of ascorbic acid, dissolved in 20 g of demineralized water, added in succession and stirred.
- the reaction solution is then left to stand without stirring, a solid gel being formed by the onset of polymerization, in the course of which the temperature rises to approximately 89.degree.
- Example 2 The procedure is analogous to Example 1, except that only a 30% aqueous solution of NaOH is used to adjust the acidic gel to a pH of 5.8.
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- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Epidemiology (AREA)
- General Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Dispersion Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Animal Behavior & Ethology (AREA)
- Hematology (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- General Chemical & Material Sciences (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Processes Of Treating Macromolecular Substances (AREA)
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2000545923A JP2002513059A (en) | 1998-04-28 | 1999-04-22 | Mechanically stable hydrogel |
EP99922121A EP1084174A1 (en) | 1998-04-28 | 1999-04-22 | Mechanically stable hydrogels |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19818852 | 1998-04-28 | ||
DE19818852.8 | 1998-04-28 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1999055767A1 true WO1999055767A1 (en) | 1999-11-04 |
Family
ID=7865977
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP1999/002702 WO1999055767A1 (en) | 1998-04-28 | 1999-04-22 | Mechanically stable hydrogels |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP1084174A1 (en) |
JP (1) | JP2002513059A (en) |
WO (1) | WO1999055767A1 (en) |
Cited By (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6562743B1 (en) | 1998-12-24 | 2003-05-13 | Bki Holding Corporation | Absorbent structures of chemically treated cellulose fibers |
WO2003043670A1 (en) | 2001-11-21 | 2003-05-30 | Basf Aktiengesellschaft | Crosslinked polyamine coating on superabsorbent hydrogels |
US7157141B2 (en) | 2000-03-31 | 2007-01-02 | Stockhausen Gmbh | Pulverulent polymers crosslinked on the surface |
US7329701B2 (en) | 2002-08-23 | 2008-02-12 | Basf Aktiengesellschaft | Superabsorbent polymers and method of manufacturing the same |
DE102006061005A1 (en) | 2006-12-22 | 2008-07-03 | Admedes Schuessler Gmbh | Workpiece i.e. stent, compressing device for protecting e.g. blood vessel, has pressure housing comprising pressure chamber for accommodation of workpiece, and compression medium provided in chamber to compress workpiece |
US7507475B2 (en) | 2001-03-07 | 2009-03-24 | Evonik Stockhausen Gmbh | Pulverulent polymers crosslinked on the surface |
US7803880B2 (en) | 2003-09-19 | 2010-09-28 | Nippon Shokubai Co., Ltd. | Water absorbent and producing method of same |
US7867623B2 (en) | 2003-10-31 | 2011-01-11 | Basf Aktiengesellschaft | Polymeric particles capable of absorbing blood and/or body fluids |
US8071202B2 (en) | 2005-04-22 | 2011-12-06 | Evonik Stockhausen Gmbh | Water-absorbing polymer structures with improved absorption properties |
WO2014034897A1 (en) | 2012-08-30 | 2014-03-06 | 株式会社日本触媒 | Particulate water-absorbing agent and method for manufacturing same |
US8946100B2 (en) | 2003-12-19 | 2015-02-03 | Buckeye Technologies Inc. | Fibers of variable wettability and materials containing the fibers |
US8952116B2 (en) | 2009-09-29 | 2015-02-10 | Nippon Shokubai Co., Ltd. | Particulate water absorbent and process for production thereof |
US9062140B2 (en) | 2005-04-07 | 2015-06-23 | Nippon Shokubai Co., Ltd. | Polyacrylic acid (salt) water-absorbent resin, production process thereof, and acrylic acid used in polymerization for production of water-absorbent resin |
US9090718B2 (en) | 2006-03-24 | 2015-07-28 | Nippon Shokubai Co., Ltd. | Water-absorbing resin and method for manufacturing the same |
US9133342B2 (en) | 2006-04-21 | 2015-09-15 | Evonik Degussa Gmbh | Preparation of highly permeable, superabsorbent polymer structures |
US9926449B2 (en) | 2005-12-22 | 2018-03-27 | Nippon Shokubai Co., Ltd. | Water-absorbent resin composition, method of manufacturing the same, and absorbent article |
WO2019137833A1 (en) | 2018-01-09 | 2019-07-18 | Basf Se | Superabsorber mixtures |
WO2019154652A1 (en) | 2018-02-06 | 2019-08-15 | Basf Se | Method for the pneumatic delivery of superabsorbent particles |
WO2019197194A1 (en) | 2018-04-10 | 2019-10-17 | Basf Se | Permeable superabsorber and method for the production thereof |
WO2021013639A1 (en) | 2019-07-24 | 2021-01-28 | Basf Se | Permeable superabsorbent and process for production thereof |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2004069293A1 (en) | 2003-02-10 | 2004-08-19 | Nippon Shokubai Co., Ltd. | Water-absorbent resin composition and its production process |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4690971A (en) * | 1985-03-05 | 1987-09-01 | Allied Colloids Limited | Water absorbing polymers |
WO1995011932A1 (en) * | 1993-10-27 | 1995-05-04 | Allied Colloids Limited | Superabsorbent polymers and products containing them |
-
1999
- 1999-04-22 JP JP2000545923A patent/JP2002513059A/en not_active Withdrawn
- 1999-04-22 EP EP99922121A patent/EP1084174A1/en not_active Withdrawn
- 1999-04-22 WO PCT/EP1999/002702 patent/WO1999055767A1/en not_active Application Discontinuation
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4690971A (en) * | 1985-03-05 | 1987-09-01 | Allied Colloids Limited | Water absorbing polymers |
WO1995011932A1 (en) * | 1993-10-27 | 1995-05-04 | Allied Colloids Limited | Superabsorbent polymers and products containing them |
US5684106A (en) * | 1993-10-27 | 1997-11-04 | Allied Colloids Limited | Superabsorbent polymers and products containing them |
Cited By (30)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6562743B1 (en) | 1998-12-24 | 2003-05-13 | Bki Holding Corporation | Absorbent structures of chemically treated cellulose fibers |
US7157141B2 (en) | 2000-03-31 | 2007-01-02 | Stockhausen Gmbh | Pulverulent polymers crosslinked on the surface |
US7507475B2 (en) | 2001-03-07 | 2009-03-24 | Evonik Stockhausen Gmbh | Pulverulent polymers crosslinked on the surface |
WO2003043670A1 (en) | 2001-11-21 | 2003-05-30 | Basf Aktiengesellschaft | Crosslinked polyamine coating on superabsorbent hydrogels |
US7329701B2 (en) | 2002-08-23 | 2008-02-12 | Basf Aktiengesellschaft | Superabsorbent polymers and method of manufacturing the same |
US7803880B2 (en) | 2003-09-19 | 2010-09-28 | Nippon Shokubai Co., Ltd. | Water absorbent and producing method of same |
US8497226B2 (en) | 2003-09-19 | 2013-07-30 | Nippon Shokubai Co., Ltd. | Water absorbent and producing method of same |
US7867623B2 (en) | 2003-10-31 | 2011-01-11 | Basf Aktiengesellschaft | Polymeric particles capable of absorbing blood and/or body fluids |
US8063265B2 (en) | 2003-10-31 | 2011-11-22 | Basf Aktiengesellschaft | Hydrogel capable of absorbing blood and/or body fluids |
US8071222B2 (en) | 2003-10-31 | 2011-12-06 | Basf Se | Polymeric particles capable of absorbing blood and/or body fluids |
US10300457B2 (en) | 2003-12-19 | 2019-05-28 | Georgia-Pacific Nonwovens LLC | Fibers of variable wettability and materials containing the fibers |
US8946100B2 (en) | 2003-12-19 | 2015-02-03 | Buckeye Technologies Inc. | Fibers of variable wettability and materials containing the fibers |
US9062140B2 (en) | 2005-04-07 | 2015-06-23 | Nippon Shokubai Co., Ltd. | Polyacrylic acid (salt) water-absorbent resin, production process thereof, and acrylic acid used in polymerization for production of water-absorbent resin |
US8071202B2 (en) | 2005-04-22 | 2011-12-06 | Evonik Stockhausen Gmbh | Water-absorbing polymer structures with improved absorption properties |
US10358558B2 (en) | 2005-12-22 | 2019-07-23 | Nippon Shokubai Co., Ltd. | Water-absorbent resin composition, method of manufacturing the same, and absorbent article |
US9926449B2 (en) | 2005-12-22 | 2018-03-27 | Nippon Shokubai Co., Ltd. | Water-absorbent resin composition, method of manufacturing the same, and absorbent article |
US9090718B2 (en) | 2006-03-24 | 2015-07-28 | Nippon Shokubai Co., Ltd. | Water-absorbing resin and method for manufacturing the same |
US9133342B2 (en) | 2006-04-21 | 2015-09-15 | Evonik Degussa Gmbh | Preparation of highly permeable, superabsorbent polymer structures |
DE102006061005A1 (en) | 2006-12-22 | 2008-07-03 | Admedes Schuessler Gmbh | Workpiece i.e. stent, compressing device for protecting e.g. blood vessel, has pressure housing comprising pressure chamber for accommodation of workpiece, and compression medium provided in chamber to compress workpiece |
US8952116B2 (en) | 2009-09-29 | 2015-02-10 | Nippon Shokubai Co., Ltd. | Particulate water absorbent and process for production thereof |
US9775927B2 (en) | 2009-09-29 | 2017-10-03 | Nippon Shokubai Co., Ltd. | Particulate water absorbent and process for production thereof |
US10189009B2 (en) | 2012-08-30 | 2019-01-29 | Nippon Shokubai Co., Ltd. | Particulate water absorbing agent and method for manufacturing same |
KR20150048785A (en) | 2012-08-30 | 2015-05-07 | 가부시키가이샤 닛폰 쇼쿠바이 | Particulate water-absorbing agent and method for manufacturing same |
WO2014034897A1 (en) | 2012-08-30 | 2014-03-06 | 株式会社日本触媒 | Particulate water-absorbing agent and method for manufacturing same |
US10525445B2 (en) | 2012-08-30 | 2020-01-07 | Nippon Shokubai Co., Ltd. | Particulate water absorbing agent and water absorbent article |
WO2019137833A1 (en) | 2018-01-09 | 2019-07-18 | Basf Se | Superabsorber mixtures |
WO2019154652A1 (en) | 2018-02-06 | 2019-08-15 | Basf Se | Method for the pneumatic delivery of superabsorbent particles |
WO2019197194A1 (en) | 2018-04-10 | 2019-10-17 | Basf Se | Permeable superabsorber and method for the production thereof |
US11986798B2 (en) | 2018-04-10 | 2024-05-21 | Basf Se | Permeable superabsorbent and process for production thereof |
WO2021013639A1 (en) | 2019-07-24 | 2021-01-28 | Basf Se | Permeable superabsorbent and process for production thereof |
Also Published As
Publication number | Publication date |
---|---|
JP2002513059A (en) | 2002-05-08 |
EP1084174A1 (en) | 2001-03-21 |
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