Abstract: The invention relates to environment management, particularly to methods for purifying a wastewater in order to climate a toxic impact of heavy and radioactive metals. A method for purifying fresh, combined and saline wastewater from radioactive and heavy metals using an electrolysis and a special active substance (sorbent), wherein the wastewater is fed to an electrolyzer with a chamber that is separated by a special membrane that is permeable for ions of metals separately of water, then changes of the pH occur in order to form complex compounds, which comprise ions of radioactive and heavy metals. Afterwards, the adsorption of the obtained compounds by the special active substance (sorbent) and filtering-off on a precoat filter that retains ions of heavy and radioactive metals are performed. The obtained filtrate is cemented without drying and evaporation in order to perform final deposition of the radioactive compounds.

Abstract: The present disclosure relates to a preparation method of a super absorbent polymer capable of improving absorption performance of the super absorbent polymer by adding a simple additive later. The preparation method includes the steps of: forming a hydrogel polymer by cross-linking and polymerizing a water-soluble ethylene-based unsaturated monomer having at least partially neutralized acidic groups in the presence of an internal cross-linking agent; drying, pulverizing and classifying the hydrogel polymer to form a base resin powder; forming a surface cross-linked layer by further cross-linking a surface of the base resin powder in the presence of a surface cross-linking agent, adding a monovalent to trivalent metal cation on the surface cross-linked base resin powder at a temperature of 25° C. to 80° C., and maintaining and aging the resulting metal cation-added product at a temperature of 40° C. to 60° C. for 10 to 30 minutes.

Abstract: The method and materials of this invention make possible substantially faster techniques for organic-aqueous extractions and routine chemical reactions work-ups. The inventive material uses silicone elastomer-coated glass powders, magnetic powders, and sponges as absorbents to extract organic products from an aqueous mixture. After separation from the mixture, these different forms now loaded with organic products can serve as a convenient input for flash chromatographic separations or other processing. With these techniques, tedious liquid-liquid extractions are replaced by a simple solid filtration or transfer and emulsion formation is eliminated. These versatile sorbents can also be used for larger scale work-ups, various extractions of organics from an aqueous solution (e.g., water purification) or gas phase and various analytical or other applications.

Abstract: A chromatography medium includes a porous matrix and nonporous globules bound on the inner and outer surfaces of the porous matrix. The average radius of the microglobules is not more than 30% of the average pore diameter of the porous matrix. The chromatography medium can be used in affinity chromatography. A method for preparing the chromatography medium may include providing a porous starting matrix, providing a polymerization solution, and initiating polymerization of the polymerization solution in the presence of the porous starting matrix to form insoluble nonporous microglobules that are bound to the inner and outer surfaces of the porous starting matrix.

Abstract: Disclosed are water-absorbent resin particles comprising a crosslinked polymer comprising a monomer unit derived from a water-soluble ethylenically unsaturated monomer, wherein an artificial menstrual blood volume increase rate as measured in an artificial menstrual blood swelling test conducted in the order of i), ii), and iii) is 70% or more. i) putting 1.0 g of water-absorbent resin particles into a measuring cylinder with an inner diameter of 27 mm. ii) injecting 10 ml of artificial menstrual blood into the cylinder at once to swell the water-absorbent resin particles. iii) measuring a volume (A) of the swollen water-absorbent resin particles after 60 seconds from the injection and calculating an artificial menstrual blood volume increase rate according to Equation (I) below. Artificial menstrual blood volume increase rate (%)=(A?B)/B×100 . . . (I), A . . . Volume (ml) of swollen water-absorbent resin particles, B . . . Volume (ml) of injected artificial menstrual blood.

Abstract: A composite material containing a porous body having pores inside the porous body and a porous coordination polymer compound (PCP), in which the porous body has a network structure of Si—O bonds obtained by copolymerizing a dialkoxysilane and a trialkoxysilane, and the porous coordination polymer compound is carried in the pores of the porous body. Also, a method for producing a composite material containing a porous body having pores inside the porous body and a porous coordination polymer compound, in which the porous body has a network structure of Si—O bonds obtained by copolymerizing a dialkoxysilane and a trialkoxysilane, and the porous coordination polymer compound is carried in the pores of the porous body via a solvent.

Abstract: Provided is a water-absorbent resin that quickly absorbs water, even in sandbag in which a large amount of the water-absorbent resin has been used, that does not easily form unswollen lump, and that has a high gel swelling volume when water is used to swell the water-absorbent resin. This water-absorbent resin is configured from a polymer of water-soluble ethylenic unsaturated monomers. The physiological-saline absorption capacity of the water-absorbent resin is 40-60 g/g. When a cross-sectional image of the water-absorbent resin is observed by x-ray computed tomography, the fraction of the area of the cross-sectional image that is hollow portions (the hollow area ratio of the cross-sectional image), as calculated on the basis of formula (I), is no more than 10%.

Abstract: A process for producing superabsorbents, comprising polymerization of a monomer solution and thermal surface postcrosslinking, wherein the monomer solution comprises at least 0.75% by weight of a hydroxyphosphonic acid or salts thereof, calculated on the basis of the total amount of monomer used, and at least 0.09% by weight of aluminum cations, calculated on the basis of the total amount of polymer particles used, is added to the polymer particles before, during or after the thermal surface postcrosslinking.

Abstract: The present invention relates to an organic-inorganic hybrid nanoporous material, maintaining a nanoporous skeleton structure formed by coordination of an organic ligand containing an aromatic compound to a trivalent central metal ion, and further having an intramolecular acid anhydride functional group modified on the aromatic compound of the nanoporous skeleton structure, and thereby exhibits selectivity for olefins, and an adsorbent comprising the same. Specifically, the organic-inorganic hybrid nanoporous material of the present invention exhibits an excellent olefin-selective adsorption capacity through differences in adsorption equilibrium and adsorption rate, and thus can be usefully employed in the separation of C2-C4 hydrocarbons.

Abstract: The present disclosure relates to a super absorbent polymer exhibiting improved rewetting property and excellent absorption property, and a preparation method of the same. This preparation method of a super absorbent polymer includes the steps of: preparing a base resin in which an acrylic acid-based monomer having at least partially neutralized acidic groups and an internal cross-linking agent are cross-linked and polymerized; and heating the base resin in the presence of a surface cross-linking agent to carry out surface modification, wherein the internal cross-linking agent includes a poly(meth)acrylate of polyols-based first internal cross-linking agent and a polyglycidyl ether of polyols-based second internal cross-linking agent in a specific weight ratio.

Abstract: The invention provides a composite material formed from an inorganic mesoporous, or mesoporous-like, material that is dispersed throughout a polymeric matrix formed by a crosslinked polymer that has acidic- or basic-residues and which may also optionally have further acidic- or basic-residues grafted onto the inorganic mesoporous material. The resulting composite material may be used to remove acidic or basic impurities from a gas in need thereof and can be easily regenerated.

Abstract: Disclosed are water-absorbent resin particles comprising a crosslinked polymer comprising a monomer unit derived from a water-soluble ethylenically unsaturated monomer, wherein an initial swelling force as measured according to a swelling force test conducted by a predetermined method is 8 N or more, and further, a ratio of the particles having a particle diameter of more than 250 ?m and 850 ?m or less is 70% by mass or more and a ratio of the particles having a particle diameter of 250 ?m or less is 20% by mass or less, with respect to the total amount of the water-absorbent resin particles.

Abstract: A porous formed article includes an organic polymer resin and an inorganic ion adsorbent and having the most frequent pore size of 0.08 to 0.70 ?m measured with a mercury porosimeter. Such a porous formed article can be prepared by crushing and mixing a good solvent for the organic polymer resin and the inorganic ion adsorbent to obtain slurry; dissolving the organic polymer resin and a water-soluble polymer in the slurry; shape-forming the slurry; promoting coagulation of the shape-formed product by controlling the temperature and humidity of a spatial portion coming into contact with the shape-formed product, until the shape-formed product is coagulated in a poor solvent; and coagulating the coagulation-promoted shape-formed product in a poor solvent. A production apparatus can be used to prepare such a porous formed article.

Abstract: A water absorbent agent having a high water absorption multiplying factor where stickiness after absorbing liquid can be reduced when used as a hygienic material is produce by a method for manufacturing the water absorbing agent. The method for manufacturing a water absorbent agent having a centrifuge retention capacity (CRC) of 30 g/g or greater, includes subjecting an aqueous solution of a monomer that includes an acrylic acid (salt) to a polymerization step, a drying step, and a surface cross-linking step, and a step for adding ?-hydroxycarboxylic acid (salt) before the drying step. The atomic weight of the soluble portion eluted when the water absorbent agent absorbs liquid and swells can be reduced by the ?-hydroxycarboxylic acid (salt) before the drying step to reduce the stickiness of the water absorbent agent after absorption of liquid, which leads to discomfort during use of disposable diapers and the like.

Abstract: An absorbent disposable article, such as a diaper, panty diaper, panty liner, sanitary napkin or incontinence device is disclosed. The article has a porous polymer-based structure obtainable by a process of: (a) depositing and photopolymerizing, layer-by-layer in accordance with a predetermined 3D model, an emulsion having an external continuous phase surrounding droplets of an internal phase having has one or more photopolymerizable monomers and/or oligomers and a photopolymerization initiator; and (b) removing the internal phase from the continuous polymer phase formed from the one or more photopolymerizable monomers and/or oligomers. The process produces a monolithic porous structure having three types of pores: (i) pores resulting from the location from which the internal phase was removed, (ii) pores interconnecting the pores according to (i), and (iii) pores as predetermined by the 3D model. The invention also relates to a method of making the article.

Abstract: The invention relates to systems and methods for recharging sorbent materials and other rechargeable dialysis components. The systems and methods include rechargers, flow paths, and related components for connecting multiple rechargers together to sharing infrastructure and resources. The rechargeable dialysis components can include zirconium phosphate, zirconium oxide, and other sorbent cartridge materials including any combination thereof or any other rechargeable component of a dialysis system. Additionally, a single-use cartridge or a multi-use cartridge can be used in the present invention.

Abstract: An endotoxin adsorbent comprising a crystalline cellulose having a nitrogen atom-containing cationic group can sufficiently remove endotoxin from a material containing endotoxin to be removed and containing a substance having a cationic group and can efficiently remove endotoxin also from a highly viscous material. The nitrogen atom-containing cationic group may be typically a functional group derived from a polyvalent amine and/or a quaternary ammonium salt. The crystalline cellulose having a nitrogen atom-containing cationic group may comprise the nitrogen atom-containing cationic group at a content of 0.05 to 3 meq/dry·g in terms of anion exchange capacity.

Abstract: To provide a molded article which can have excellent strength, can also have high durability during repeated use, and can maintain high adsorption performance even when the content of a binder resin is reduced. A molded article containing cerium oxide particles and a binder resin, wherein cerium oxide particles which has an average particle diameter of 1 to 15 ?m and in each of which a crystallite size is 40 to 200 ? are used.

Abstract: A honeycomb body having a porous ceramic honeycomb structure with a first end, a second end, and a plurality of walls having wall surfaces defining a plurality of inner channels. A highly porous layer is disposed on one or more of the wall surfaces of the honeycomb body. The highly porous layer has a porosity greater than 90%, and has an average thickness of greater than or equal to 0.5 ?m and less than or equal to 10 ?m. A method of making a honeycomb body includes depositing a layer precursor on a ceramic honeycomb body and binding the layer precursor to the ceramic honeycomb body to form the highly porous layer.

Abstract: A water-absorbent resin that exhibits a high liquid-retention capacity under a load and a small amount of re-wet, even when it is used in an absorbent material having a low proportion of hydrophilic fibers. The water-absorbent resin includes a polymer of a water-soluble ethylenically unsaturated monomer, wherein when a cross-sectional image of the water-absorbent resin is observed using X-ray computed tomography, the water-absorbent resin has cavity area percentage in the cross-sectional image of 10% or less.

Abstract: Provided is a stationary phase for supercritical fluid chromatography, the stationary phase having satisfactory molecule-identifying ability, in particular, satisfactory separating properties with respect to not only acidic compounds or basic compounds but also fused aromatic compounds or aromatic isomers. The stationary phase for supercritical fluid chromatography includes a support having, bonded thereto, a polymer in which the main chain has nitrogenous aromatic rings in the repeating units.

Abstract: Provided is a resin bead comprising functional groups of structure (S1).

Abstract: A super absorbent polymer according to the present invention has excellent dryness while maintaining excellent absorption performance, and thus is preferably used for hygienic materials such as diapers, and can exhibit excellent performance.

Abstract: The present invention relates to a superabsorbent polymer that not only has excellent basic absorption performance, but also exhibits more improved absorption speed, permeability, etc., and a method for preparing the same. The superabsorbent polymer includes a base polymer powder including: a first crosslinked polymer of water soluble ethylenically unsaturated monomers having acid groups of which at least a part are neutralized; and a surface crosslink layer that is formed on the base polymer powder, and further includes a second crosslinked polymer in which the first crosslinked polymer is additionally crosslinked by a C2-5 alkylene carbonate, wherein an absorption degree, SFC, an absorption speed, and a porosity fulfill specific ranges.

Abstract: Disclosed herein are cyclodextrin molecules covalently modified to store and release nitric oxide, as well as methods of making and uses thereof. The covalently modified cyclodextrin molecules may be tailored, in several embodiments, to release nitric oxide in a controlled manner and are useful for reduction and/or eradication of bacteria and for the treatment of disease.

Abstract: The present invention relates to a super-absorbent polymer having excellent properties, both centrifugal retention capacity (CRC) and absorption under pressure (AUP) having been improved by introducing a surface crosslinked layer crosslinked by surface-modified inorganic particles, and to a method for preparing the same. The super-absorbent polymer comprises: a base resin powder containing a crosslinked polymer of water-soluble ethylene-based unsaturated monomers having an at least partially neutralized acidic group; and a surface crosslinked layer formed on the base resin powder, wherein inorganic particles may be chemically bound to the crosslinked polymer contained in the surface crosslinked layer, via an oxygen-containing bond or a nitrogen-containing bond.

Abstract: A method for producing a medical device, and a medical device are provided, and the production method includes a step of heating a device together with a solution containing a polymer having the following repeating unit (A) and the following repeating unit (B), or a step of bringing a device into contact with a heated product of a solution containing a polymer having the following repeating unit (A) and the following repeating unit (B): (A) a hydrophilic repeating unit; and (B) a repeating unit having a polyoxyalkylene group in a side chain, the terminal of the side chain being composed of an alkyl group having 5 to 30 carbon atoms, an alkanoyl group having 5 to 30 carbon atoms, or an aryl group having 6 to 30 carbon atoms.

Abstract: To provide a water-absorbing resin composition having both a high centrifuge retention capacity (CRC) and a sufficient urine resistance and a method for producing such a water-absorbing resin composition, an aspect of the present invention is a water-absorbing resin composition having the following properties: (1) A centrifuge retention capacity (CRC) being not less than 35 g/g; (2) A post-degradation-test one-hour eluted soluble component being not more than 19% by mass; (3) An absorbency against pressure 0.7 psi (AAP0.7) being not less than 10 g/g; and (4) A content of a water-absorbing resin in dust being not more than 300 ppm with respect to a total mass of the water-absorbing resin composition.

Abstract: A multi-ply absorbent sheet includes a first absorbent ply of cellulosic sheet; a second absorbent ply of cellulosic sheet; and a ply bonding adhesive interposed between the first absorbent ply and the second absorbent ply, the ply-bonding adhesive thereby adhering said absorbent plies together. The ply-bonding adhesive comprises polyvinyl alcohol and nanofibrillated cellulose. In a particularly preferred embodiment the adhesive is applied as a dilute aqueous composition to tissue plies and the nanofibrillated cellulose has a Characteristic Breaking Length of 6.5 km or above.

Abstract: A method of forming a scaffold comprises the steps of: preparing a high internal phase emulsion (HIPE) comprising an aqueous solution of: proteins selected from the group consisting of collagen and mixtures of collagen and chitosan; and a cross-linking agent; by addition of an immiscible solvent to the solution to form the HIPE; reducing the temperature of the HIPE to solidify the HIPE; removing water and solvent by vaporisation at a temperature above the melting point of the solvent to form a porous structure; and before or after removal of solvent, causing cross-linking of the protein with the cross-linking agent to form a crosslinked scaffold structure.

Abstract: The present invention relates to a manufacturing method of a super absorbent polymer. More specifically, the present invention relates to a manufacturing method of a super absorbent polymer capable of reducing energy, reducing a process cost, and reducing a load on a device, at the time of drying due to reduction in an amount of water used during reassembly of fines, while manufacturing a super absorbent polymer exhibiting a reduced generation amount of re-fines and having excellent physical properties.

Abstract: An absorbent pad has: a first, outer layer comprising a permeable or non-permeable film; a second, outer layer comprising a permeable or non-permeable film, placed on a side of the pad opposite the first, outer layer; a third layer disposed between the first layer and the second layer, and comprising a tissue laminate comprising at least a first ply and a second ply, with at least one chemical agent or system fixed in the third layer and being either activated by contact with or soluble in an aqueous liquid, the at least one chemical agent or system being in a predetermined amount distributed substantially uniformly per unit area of the surface area between the at least first ply and second ply: and a fourth layer disposed between the first layer and the second layer and comprising fluff, with or without a chemical agent or system, the third layer being joined to the fourth layer to serve as a substrate for the fourth layer.

Abstract: Adsorbent polymeric structures are described. These adsorbent polymeric structures are capable of separating non-polar hydrocarbons, such as crude oil or diesel fuel, from polar liquids, such as water. The adsorbent polymeric structures may include acid grafted graphene and at least one styrene. A method of preparing an adsorbent polymeric structure may include mixing graphene and at least one acid catalyst in a polar liquid in the presence of at least one alcohol to form an acid grafted graphene via an esterification reaction; and the acid grafted graphene and at least one styrene monomer are introduced to water in the presence of an initiator to form the adsorbent polymeric structure according to any of the previously-described embodiments via an emulsion polymerization reaction. Moreover, the adsorbent polymeric structures may be incorporated into methods of fluidly separating at least one non-polar hydrocarbon from a polar liquid.

Abstract: A composition configured to create a superhydrophobic surface includes a fluorinated hydrophobic component dispersible in an aqueous dispersion; cellulosic elements of a size ranging from 100 nm to 100 ?m; and water. The hydrophobic component is selected from the group consisting of fluorinated polymers, perfluorinated polymers, and mixtures thereof; and the cellulosic elements are micro- and nano-fibrillated cellulose. A disposable absorbent article includes a substrate having a surface, the surface including a composition including a fluorinated hydrophobic component dispersible in an aqueous dispersion; cellulosic elements of a size ranging from 100 nm to 100 ?m; and water, wherein the surface exhibits a contact angle greater than 150 degrees.

Abstract: The present invention relates to a super absorbent polymer and a production method thereof which enable production of a super absorbent polymer exhibiting a more improved absorption rate while maintaining excellent absorption characteristics.

Abstract: In accordance with the present subject matter there is provided a compound of Formula I wherein, R1 is substituted C1 to C10 alkyl; and R2 is substituted C1 to C10 alkyl, a process for preparing a compound of Formula I, and a gel comprising a compound of Formula I. There is also provided a process for separating a hydrophobic material from a mixture of hydrophobic and hydrophilic material using a compound of Formula I.

Abstract: A polyelectrolyte coated fly ash is described with a method of making and a method of using for the adsorption of a contaminant from a solution. The polyelectrolyte coated fly ash may be made by treating the oil fly ash with acid, and then contacting the product with a positive polyelectrolyte to create a first polyelectrolyte layer, and then with a negative polyelectrolyte to create a negative polyelectrolyte layer. The resulting polyelectrolyte coated fly ash quickly adsorbs contaminants from solution, and may be cleaned and reused.

Abstract: An engineered collection medium for use in mineral separation is described. The engineered collection medium has a solid phase body configured with a three-dimensional open-cell structure like foam or sponge to provide collection surfaces. The surfaces are functionalized with a hydrophobic chemical having molecules with a functional group for attaching mineral particles to the collection surfaces. The engineered collection medium can be a foam block, a filter or conveyor belt to be placed in a slurry to collect mineral particles in the slurry. The engineered collection medium carrying the mineral particles is provided to a release apparatus where the mineral particles can be released by using mechanical agitation, sonic agitation and so forth.

Abstract: A superabsorbent polymer composition includes superabsorbent polymer particles, having a crosslinked polymer of water-soluble ethylenically unsaturated monomers including acid groups, of which at least a part are neutralized; and a particulate antimicrobial agent having a quaternary ammonium salt of a silane-based compound. The superabsorbent polymer composition exhibits improved antimicrobial and deodorizing properties without deterioration of the superabsorbent polymer properties such as centrifugal retention capacity.

Abstract: A method of water treatment includes flowing water that includes nitrogen and phosphorus compounds through a sorption media composition within at least one chamber of a water treatment system. The composition comprises iron filings comprising at most 5 volume (vol) % of the composition, sand particles comprising at least 80 vol % of the composition, and clay particles comprising at most 5 vol % of the composition. The iron filings, sand particles, and clay particles are mixed together. During the flowing, the clay particles attract the nitrogen and phosphorus compounds, which become absorbed onto a surface of the iron filings and the clay, resulting in a removal of the nitrogen and phosphorus compounds and the generation of reaction products. Nitrogen and phosphorus are then recovered from the reaction products.

Abstract: Amine functional solid sorbents for carbon dioxide capture and sequestration may be prepared from metal oxide foam solid sorbent supports by treating an appropriate metal oxide foam solid sorbent support with an amine material. Desirable are metal oxide foam solid sorbent supports with a foam structure and morphology at least substantially absent hollow sphere, layered sphere, wormlike and amorphous structure and morphology components. The amine materials may be sorbed into the metal oxide foam solid sorbent support, or alternatively chemically bonded, such as but not limited to covalently bonded, to the metal oxide foam solid sorbent support.

Abstract: The present invention provides a separating medium including porous resin particles which has a sufficient pore diameter suitable for liquid chromatography applications and which has high strength, is reduced in pressure loss during liquid passing, has the excellent property of separating a desired substance, and has low nonspecific adsorption properties. The separating medium of the invention is a separating medium obtained by treating porous epoxy resin particles and having an average pore diameter of 10 to 2,000 nm, or a separating medium obtained by treating porous epoxy resin particles and having a water content of 50% or higher.

Abstract: A method for producing a hydrocarbon absorber by extraction and processing of vegetable fibers from the Australian king palm (Archontophoenix cunninghamiana), discarded as waste by the agricultural industry and possessing a high hydrocarbon sorption and agglutination capacity in land environments.

Abstract: A flooring panel is provided with a quick-release adhesive sheet such that the flooring panel can be quickly attached to a support surface and removed therefrom. More particularly, the flooring panel includes a top floor layer attached or laminated to the adhesive sheet, which underlies the floor layer. The top flooring layer can be any type of flooring material, such as vinyl flooring, real or engineered wood flooring, etc.

Abstract: Apparatus or recovering a mineral particle of interest from a slurry in a mineral extraction process, featuring a core or substrate; and multiple layers arranged on the core or substrate, each layer of the multiple layers configured with a respective outer surface having a plurality of molecules attached thereto, the molecules comprising a functional group selected for attracting and attaching one or more mineral particles of interest to the molecules. Each layer is made from a polymer having a thickness of less than or equal to about 125 microns. The polymer is selected from a group consisting of polydimethylsiloxane or dimethyl siloxane.

Abstract: The present invention relates to an attrition-resistant superabsorbent polymer comprising a superabsorbent polymer; water; and at least three selected from the group consisting of particles having i) a BET specific surface area of 300 to 1500 m2/g and ii) a porosity of 50% or more, a multivalent metal salt, an organic acid and a polyhydric alcohol, and a preparation method thereof.

Abstract: Provided is a water absorption treatment material and a method for manufacturing the same, according to which a clump can be formed after use without incurring a decrease in water absorptivity. A water absorption treatment material includes a granular core portion and an embedded portion. A recessed portion is formed on the surface of the granular core portion. The embedded portion is provided in the recessed portion of the granular core portion. The embedded portion contains an adhesive material.

Abstract: Provided herein are systems, and methods of using such systems, for producing superabsorbent polymers from ethylene oxide and carbon monoxide. The production systems have various unit operations, including, for example, a (?-propiolactone production system configured to produce (?-propiolactone from ethylene oxide and carbon monoxide and a superabsorbent polymer production system configured to produce superabsorbent polymers from (?-propio lactone and/or acrylic acid.

Abstract: The present invention relates to a super absorbent polymer and a method for preparing the same. According to the super absorbent polymer and the method for preparing a super absorbent polymer of the present invention, a laponite is contained in a colloidal solution state during polymerization of the monomer composition, and thus achieves an appropriate crosslinking density, thereby contributing to improvement of various physical properties such as a gel strength and a centrifuge retention capacity of the super absorbent polymer.

Abstract: The present invention provides a novel acrylic acid crosslinked polymer and the use thereof. The present invention provides the acrylic acid crosslinked polymer in which the content of soluble components is 40 wt. % or higher. The present invention also provides a method for adjusting the viscosity of a fracturing fluid in a hydraulic fracturing method, the viscosity adjustment method including: A) a step of measuring the types and quantities of metal cations which are in water and which are the object of viscosity adjustment; B) a step of selecting the type and quantity of an acrylic acid crosslinked polymer on the basis of the types and quantities of metal cations and the pH so as to achieve a viscosity that is required for fracturing in a hydraulic fracturing method; and C) a step of adjusting the viscosity of the fracturing fluid using the acrylic acid crosslinked polymer of the selected type and quantity.