TWI727827B - Superabsorbent polymer composition, superabsorbent polymer, and method for producing the same - Google Patents

Abstract

The present invention relates to a superabsorbent polymer composition, a superabsorbent polymer, and a method for producing the same. By a specific structure of a first internal crosslinking agent, the superabsorbent polymer produced according to the method in the present invention has a good antibacterial property and a long-term absorption capacity.

Description

Water-absorbent resin composition, water-absorbent resin and manufacturing method thereof

The present invention relates to a water-absorbent resin composition, a water-absorbent resin and a manufacturing method thereof, and in particular to a water-absorbent resin composition, a water-absorbent resin and a manufacturing method thereof that have both good antibacterial ability and long-term absorption capacity method.

Water-absorbent resins are widely used in water retention agents in agriculture or gardening, anti-dew coagulants for building materials, materials for removing water from petroleum, waterproof coatings for the outer layer of cables, and sanitary products. For example, diapers, feminine hygiene products and disposable wipes, among which diapers are the largest.

At present, functional diapers are the main development direction, especially adult diapers. In addition to emphasizing absorptive capacity and dryness, it is also developing towards anti-bacterial ability. Based on the demand for antibacterial ability, various researches are actively being carried out to develop water-absorbent resins with antibacterial ability and long-term absorption ability.

With the global increase in raw materials, the price of pulp has also risen rapidly, and the tendency of water-absorbent resins to replace paper pulp is becoming more and more obvious. In addition to having the characteristics of long-term absorption capacity, it must also have antibacterial capacity to avoid the growth of bacteria during the long period of use, which will cause the user's skin to develop red rashes.

In order to make the water-absorbent resin meet the above-mentioned requirements, a well-known method in the technical field of the present invention is to increase the water absorption capacity by increasing the degree of neutralization. Another way is to add a copolymer to improve water absorption. For example, use a copolymer of acrylic acid and acrylamide, and control the polymerization temperature in the range of 50 to 110°C (US Patent Publication No. 5496890), but residual propylene Amide is harmful to the human body when used.

In addition, graft polymerization is used to improve the water absorption capacity of water-absorbent resins, for example: superabsorbent resins made by adding konjac flour (Chinese Patent Publication No. 1410463A) and starch and cellulose (Chinese Patent Application No. 200410050060.0), It has the advantages of high absorption rate and high absorption speed. However, after absorbing water, the gel strength of this grafted water-absorbent resin is low, which easily causes dissolution loss and affects water retention capacity. Furthermore, the starch chain segment is also susceptible to microbial damage, and loses its water retention capacity and reduces its service life.

In addition, World Patent Publication No. WO2003028778 mentions a method for preparing a water-absorbent resin with antibacterial ability by lowering the pH value of the water-absorbent resin. Furthermore, US Patent Publication No. 20010053807 mentions that the addition of aminoacetic acid can reduce the occurrence of odor. However, the water-absorbent resin prepared by the above method has poor resistance to urine under pressure.

By mixing tannin (Gallotannin) (US Patent Publication No. 8658146) and its derivatives with a water-absorbent resin, a water-absorbent resin with deodorizing ability can be produced. However, due to the high cost and high temperature and humidity conditions , Water-absorbent resin has the problem of turning yellow or brown, and is not suitable for long-term storage.

In addition, the use of activated carbon, nanosilver ions or zeolite coated with silver ions can also reduce the occurrence of odor or bacterial growth (US Patent Publication No. 6663949, European Patent Publication No. 1404385 and US Patent Publication No. 7868075 ). European Patent Publication No. 1275404 mentions that mixing cyclodextrin or a derivative thereof with a water-absorbent resin can reduce the occurrence of odor. In addition, heat treatment of 1,2 decanediol and a water-absorbent resin can reduce the occurrence of odor (U.S. Patent No. 20150306272). However, none of these patents can provide both antibacterial and deodorizing capabilities at the same time, and they only have better suppression capabilities for ammonia.

In addition, U.S. Patent Publication No. 8,647,317 mentions that silane derivatives can increase the long-term absorption of water-absorbent resins, but silane derivatives have the disadvantages of high price and poor stability.

In view of this, there is an urgent need to develop a water-absorbent resin composition, a water-absorbent resin and a manufacturing method thereof that have both good antibacterial ability and long-term absorption capacity, so as to improve the above-mentioned shortcomings of conventional water-absorbent resins.

Accordingly, one aspect of the present invention is to provide a water-absorbent resin composition, in which the water-absorbent resin prepared by the first internal crosslinking agent with a specific structure has both good antibacterial properties and long-term absorption. ability.

Another aspect of the present invention is to provide a method for producing a water-absorbent resin, which uses the aforementioned water-absorbent resin composition to prepare the water-absorbent resin of the present invention.

Another aspect of the present invention is to provide a water-absorbent resin. The water-absorbent resin is prepared by the aforementioned manufacturing method, and the water-absorbent resin has organic acid ester bonds. When the organic acid ester bond is hydrolyzed, the generated hydroxyl group and the released organic acid can respectively provide long-term absorption capacity and good antibacterial properties.

(I)。 According to one aspect of the present invention, a water-absorbent resin composition is provided. The water-absorbent resin composition has an acid group-containing monomer aqueous solution, an internal crosslinking agent, a polymerization initiator, and a surface crosslinking agent. The degree of neutralization of the acid group-containing monomer aqueous solution ranges from 45 mol% to 85 mol%. The internal crosslinking agent includes a first internal crosslinking agent, wherein the first internal crosslinking agent includes an ester compound having a structure as shown in formula (I):

(I).

In the above formula (I), X represents a linear or branched alkenyl group having a carbon number of 3 to 5, and the end of X away from Y is a double bond structure; n represents 8 to 15; and a plurality of Y independently represents Ethylene glycol or propylene glycol group, and the oxygen atoms of the ethylene glycol group and propylene glycol group are bonded to X; Z represents a substituted saturated linear carboxyl group with 3 to 7 carbon atoms, and the end of Z away from the carbon atom is a carboxyl structure , The substituent of the saturated linear carboxyl group includes a hydroxyl group, and the number of the hydroxyl group is 1 to 3.

According to an embodiment of the present invention, the acid group-containing monomer aqueous solution contains a neutralized acid group-containing monomer, and based on the usage amount of the acid group-containing monomer aqueous solution is 100 parts by weight, the neutralized acid group-containing monomer The usage amount is 20 parts by weight to 55 parts by weight.

According to another embodiment of the present invention, based on the total usage amount of the neutralized acid group-containing monomer, internal crosslinking agent and polymerization initiator is 100 parts by weight, the usage amount of the internal crosslinking agent is 0.001 parts by weight to 5 parts by weight.

According to another embodiment of the present invention, the internal crosslinking agent optionally includes a second internal crosslinking agent, and the second internal crosslinking agent is selected from amines with acrylic groups, esters with acrylic acid, and at least two A group of ethylene oxide ethers and any combination thereof.

According to another embodiment of the present invention, based on the usage amount of the internal crosslinking agent being 100% by weight, the usage amount of the first internal crosslinking agent is not less than 20% by weight.

(I)。 Another aspect of the present invention is to provide a method for manufacturing a water-absorbent resin. The manufacturing method of the water-absorbent resin first provides an acid group-containing monomer aqueous solution, wherein the neutralization degree of the acid group-containing monomer aqueous solution ranges from 45 mole percent to 85 mole percent. Then mix the internal crosslinking agent, the polymerization initiator and the acid group-containing monomer aqueous solution to carry out free radical polymerization to prepare the hydrogel, wherein the internal crosslinking agent includes a first internal crosslinking agent, and the first The internal crosslinking agent includes an ester compound having a structure as shown in formula (I):

(I).

In the above formula (I), X represents a linear or branched alkenyl group with a carbon number of 3 to 5, and the end of X away from Y has a double bond structure; n represents 8 to 15; and the plural Ys are each independently Represents a glycol group or a propylene glycol group, and the oxygen atoms of the ethylene glycol group and the propylene glycol group are bonded to X; Z represents a substituted saturated linear carboxyl group with 3 to 7 carbon atoms, and the end of Z away from the carbon atom is a carboxyl group In the structure, the substituent of the saturated linear carboxyl group contains a hydroxyl group, and the number of the hydroxyl group is 1 to 3. Then, a surface cross-linking agent is used to perform a surface cross-linking reaction on the hydrogel to prepare a water-absorbent resin.

According to an embodiment of the present invention, the total usage amount of the neutralized acid group-containing monomer, internal crosslinking agent and polymerization initiator contained in the acid group-containing monomer aqueous solution is 100 parts by weight, and the internal crosslinking agent The usage amount of is 0.001 parts by weight to 5 parts by weight.

According to another embodiment of the present invention, the internal crosslinking agent optionally includes a second internal crosslinking agent, and the second internal crosslinking agent is selected from amines with acrylic groups, esters with acrylic acid, and at least two A group of ethylene oxide ethers and any combination thereof.

According to another embodiment of the present invention, based on the usage amount of the internal crosslinking agent being 100% by weight, the usage amount of the first internal crosslinking agent is not less than 20% by weight.

Another aspect of the present invention is to provide a water-absorbent resin. The water-absorbent resin is prepared by the aforementioned method for producing water-absorbent resin, wherein the water-absorbent resin has organic acid ester bonds.

The method for producing the water-absorbent resin composition and the water-absorbent resin of the present invention, wherein the first internal crosslinking agent with a specific structure and a specific amount of use is used to prepare the water-absorbent resin with good absorption capacity for synthetic urine , And at the same time has excellent antibacterial function. Furthermore, with regard to the water-absorbent resin of the present invention, during production, the particles will not leak out of the production equipment, or even suspend in the air of the workshop, thereby harming the respiratory tract of personnel.

The manufacture and use of the embodiments of the present invention are discussed in detail below. However, it is understandable that the embodiments provide many applicable inventive concepts, which can be implemented in various specific contents. The specific embodiments discussed are for illustration only, and are not intended to limit the scope of the present invention.

The water-absorbent resin composition of the present invention includes an acid group-containing monomer aqueous solution, an internal crosslinking agent, a polymerization initiator, and a surface crosslinking agent. The aforementioned acid group-containing monomer aqueous solution contains water as a solvent and an acid group-containing monomer as a solute, in which an acid group-containing single-system water-soluble unsaturated monomer. In some embodiments, the acid group-containing monomer may include, but is not limited to, an acrylic compound, other suitable acid group-containing unsaturated monomer compounds, or any combination of the foregoing compounds. In some specific examples, the acrylic compound may include, but is not limited to, acrylic acid, methacrylic acid, and 2-propenylamine-2-methylpropanesulfonic acid. In other specific examples, other suitable unsaturated monomer compounds containing acid groups may include, but are not limited to, maleic acid, maleic anhydride, fumaric acid and fumaric anhydride. Group of unsaturated compounds.

In other embodiments, the acid group-containing monomer may optionally include other hydrophilic monomer compounds with unsaturated double bonds. In some specific examples, other hydrophilic monomer compounds with unsaturated double bonds may include but are not limited to acrylamide, methacrylamide, 2-carboxyethyl acrylate, 2-carboxyethyl methacrylate, acrylic acid Compounds with unsaturated double bonds such as methyl ester, ethyl acrylate, dimethylamine propylene acrylamide, and propylene acrylamide trimethyl ammonium chloride. However, it is understandable that the usage amount of the aforementioned unsaturated monomer compound containing acid groups is based on the principle that the physical properties of the water-absorbent resin are not damaged.

In addition, neutralizing the carboxyl group of the acid group-containing monomer can adjust the pH value of the acid group-containing monomer aqueous solution. In some embodiments, the pH value of the acid group-containing monomer aqueous solution is equal to or greater than 5.5, and preferably 5.6 to 6.5. The aforementioned neutralization can be accomplished using a neutralizing agent. When the neutralization degree of the acid group-containing monomer aqueous solution is less than 45 mole percent, the pH value of the acid group-containing monomer aqueous solution is less than 5.5, and the residual monomer content in the hydrogel after polymerization is too high, resulting in the physical properties of the water-absorbent resin Poor, and affect the long-term absorption capacity of the absorber.

In some embodiments, the neutralizer may include, but is not limited to, hydroxides, carbonic acid compounds, or combinations of alkali gold elements or alkaline earth elements, and/or other suitable alkaline compounds. In a specific example, the neutralizer may include, but is not limited to, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, ammonia compounds, or a combination thereof. The neutralizer can be used alone or in combination of multiple neutralizers.

After the acid group-containing monomer is neutralized by the neutralizer, the acid group of the acid group-containing monomer can form salts such as sodium salt, potassium salt or ammonium salt to provide a water-absorbent resin with a pH value suitable for skin contact. In some embodiments, the neutralization degree of the acid group-containing monomer aqueous solution may be 45 mol% to 85 mol%, and preferably may be 50 mol% to 75 mol%. When the neutralization degree of the acid group-containing monomer aqueous solution is less than 45 mol%, the pH value of the water-absorbent resin finished product made from the water-absorbent resin will be low (ie, the pH is less than 5.5). When the neutralization degree of the acid group-containing monomer aqueous solution is greater than 85 mole percent, the pH value of the water-absorbent resin product made from the water-absorbent resin will be higher (pH greater than 6.5). When the pH of the finished product of the water-absorbent resin is slightly acidic (that is, the pH is 5.5) to neutral (that is, the pH is 7), the finished product of the water-absorbent resin is suitable for contact with the human body and is safer.

In some embodiments, the amount of the acid group-containing monomer used in the present invention is not particularly limited. In other embodiments, based on the usage amount of the acid group-containing monomer aqueous solution is 100 parts by weight, the usage amount of the acid group-containing monomer is 20 parts by weight to 55 parts by weight, and preferably 30 parts by weight to 45 parts by weight. When the used amount of the acid group-containing monomer is less than 20 parts by weight, the hydrogel after polymerization is too soft and sticky, which is not conducive to mechanical processing. When the used amount of the acid group-containing monomer is greater than 55 parts by weight, the concentration of the acid group-containing monomer aqueous solution is close to the saturated concentration, and it is difficult to prepare, and the polymerization reaction is too fast, and it is difficult to control the reaction heat.

In some embodiments, the aqueous acid group-containing monomer solution may optionally contain water-soluble polymers to reduce costs. In these embodiments, the water-soluble polymer may include, but is not limited to, partially saponified or fully saponified polyvinyl alcohol, polyethylene glycol, polyacrylic acid, polypropylene amide, starch and/or starch derivatives. In some specific examples, starch and/or starch derivatives may include, but are not limited to, polymers such as methyl cellulose, methyl cellulose acrylate, and ethyl cellulose.

The molecular weight of the aforementioned water-soluble polymer is not particularly limited. Preferably, the water-soluble polymer can be starch, partially saponified polyvinyl alcohol, fully saponified polyvinyl alcohol, and any combination thereof. Based on 100 parts by weight of the acid group-containing monomer aqueous solution, the use amount of the water-soluble polymer may be 0 to 20 parts by weight, preferably 0 to 10 parts by weight, and more preferably 0 to 5 parts by weight . When the amount of water-soluble polymer used is greater than 20 parts by weight, the water-soluble polymer will affect the physical properties of the water-absorbent resin, resulting in poor physical properties.

(I)。 In the water-absorbent resin composition of the present invention, the internal crosslinking agent includes a first internal crosslinking agent, and the first internal crosslinking agent includes an ester compound having a structure as shown in formula (I):

(I).

In the formula (I), X represents a linear or branched alkenyl group having a carbon number of 3 to 5, and preferably represents a linear or branched chain alkenyl group having a carbon number of 3, or a branched chain alkenyl group having a carbon number of 4 The base, where X is far from Y, has a double bond structure. The aforementioned double bond structure is used for cross-linking with acid group-containing monomers. When the alkenyl group represented by X does not have a terminal alkenyl group, the first internal crosslinking agent cannot crosslink with the acid group-containing monomer.

In the aforementioned formula (I), n represents 8-15, and preferably 9-12. When n is less than 8, the water solubility of the first internal crosslinking agent is poor, and the poor water solubility leads to poor reactivity of the first internal crosslinking agent. When n is greater than 15, the price of the first internal crosslinking agent is expensive, which is not economical.

Further, a plurality of Y independently represents an ethylene glycol group or a propylene glycol group, and is preferably an ethylene glycol group, wherein the oxygen atoms of the ethylene glycol group and the propylene glycol group are bonded to X.

In addition, Z represents a substituted saturated linear carboxyl group having 3 to 7 carbon atoms, and one end of Z away from the carbon atom has a carboxyl structure, wherein the substituent of the saturated linear carboxyl group includes a hydroxyl group, and the number of the hydroxyl group is 1 to 3. In some embodiments, the number of hydroxyl groups is one. The hydroxyl group in the aforementioned saturated linear carboxyl group can be used for cross-linking reaction with the carboxyl group of the acid group-containing monomer to form an ester bond. In some embodiments, the substituent of the saturated linear carboxyl group optionally includes a carboxyl group, and preferably, the number of the carboxyl group is 1 to 3. In other embodiments, the number of hydroxyl groups is one, and the number of carboxyl groups is zero or one.

Furthermore, the first internal crosslinking agent of the present invention uses the concept of Protecting Group in organic synthesis to react unsaturated double bond compounds with hydroxyl groups in the structure with organic acids with antibacterial properties to form unsaturated double bonds An acid ester compound (ie, an ester compound having the structure shown in the above formula (I)).

In some embodiments, specific examples of the unsaturated double bond compound having a hydroxyl group may include, but are not limited to, polyethylene glycol propylene ether, polyethylene glycol methacrylic ether, polypropylene glycol propylene ether, or polypropylene glycol methacrylic ether, etc. Ethers. The organic acid compound with antibacterial ability may include, but is not limited to, compounds such as hydroxydiacid compounds or hydroxytriacid compounds. Specific examples of the hydroxydiacid compound may be 2,3-dihydroxysuccinic acid (tartaric acid) and 2-hydroxysuccinic acid (malic acid). A specific example of the hydroxy triacid compound may be 3-hydroxy-3-carboxyglutaric acid (citric acid).

(I-1)

(I-2)

(I-3)

(I-4) In other embodiments, the ester compound may be a commercially available product. Specific examples of ester compounds may include, but are not limited to, polyethylene glycol propylene ether 2-hydroxysuccinate (n=9) (manufactured by Dorcas, and the trade name is DK450, such as formula (I-1) The structure shown), polyethylene glycol propylene ether 3-hydroxy-3-carboxyglutarate (n=9) (manufactured by Dorcas, and the trade name is DK455, as shown in formula (I-2) The structure shown), polyethylene glycol propylene ether 2-hydroxysuccinate (n=12) (manufactured by Dorcas, and the trade name is DK600, or manufactured by Longmao, and the trade name is LM6012, Such as the structure shown in formula (I-3)), polyethylene glycol propylene ether 2-hydroxysuccinate (n=10) (manufactured by Long Mao Company, and the trade name is LM4510, as in formula (I-4) ) Shows the structure).

(I-1)

(I-2)

(I-3)

(I-4)

In other embodiments, the internal crosslinking agent optionally includes a second internal crosslinking agent, wherein the second internal crosslinking agent is selected from amines with acrylic groups, esters with acrylic acid, and at least two epoxy resins. A group composed of ethers of ethane and any combination thereof.

In some specific examples, the amines with propenyl groups may include, but are not limited to, N,N'-bis(2-propenyl)amine, N,N'-methine bisacrylamide, N,N'- Amines such as methyl bismethacrylamide and N,N,N-tris(2-propenyl)amine. The esters with acrylic acid may include, but are not limited to, propylene acrylate, ethylene glycol diacrylate, polyethylene glycol diacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, triglyceride Acrylate, glycerol trimethacrylate, glycerin triacrylate or trimethacrylate with ethylene oxide added, trimethylolpropane triacrylate or trimethacrylate with ethylene oxide added, trimethylolpropane Esters such as methacrylate, trimethanol propane triacrylate, ethylene glycol diacrylate, polyoxyethylene glyceryl triacrylate, diethyl polyoxyethylene glyceryl triacrylate, and dipropylene triethylene glycol ester. The ethers having at least two ethylene oxides may include, but are not limited to, sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, polyethylene Ethers such as glycol diglycidyl ether or diglycerol polyglycidyl ether.

In some embodiments, based on the total usage amount of the neutralized acid group-containing monomer, the internal crosslinking agent, and the polymerization initiator is 100 parts by weight, the usage amount of the internal crosslinking agent is 0.001 to 5 parts by weight , And preferably 0.01 parts by weight to 3 parts by weight. When the internal crosslinking agent is used in an amount of 0.001 parts by weight to 5 parts by weight, the hydrogel after polymerization does not have viscosity, which is conducive to mechanical processing, and has good water absorption, which improves the performance of the water-absorbent resin.

In some embodiments, based on the usage amount of the internal crosslinking agent being 100% by weight, the usage amount of the first internal crosslinking agent is not less than 20% by weight, and preferably equal to or greater than 50% by weight. When the use amount of the first internal crosslinking agent is not less than 20% by weight, the first internal crosslinking agent can improve the antibacterial properties and long-term water absorption of the water-absorbent resin.

In detail, after the water-absorbent resin absorbs the liquid, the water-absorbent resin presents a weak acidity. This weak acidity causes the ester bond of the first internal crosslinking agent to be hydrolyzed to produce a hydroxyl group (that is, the hydroxyl group of the aforementioned unsaturated double bond compound) and Carboxyl group (i.e., the aforementioned carboxyl group of organic acid with antibacterial ability). This hydroxyl group generates hydrogen bonds with water molecules, thereby enhancing the absorption capacity of the water-absorbent resin. Furthermore, the ester bond formed by the hydroxyl group of the saturated linear carboxyl group represented by Z and the carboxyl group of the acid group-containing monomer can also be hydrolyzed and broken by the aforementioned weak acidity. Accordingly, organic acids are released, and the antibacterial properties of the water-absorbent resin can be provided.

Although the esters with acrylic acid in the second internal crosslinking agent (for example: polyethylene glycol diacrylate) also have ester bonds, the first internal crosslinking agent has more hydroxyl and carboxyl groups. Therefore, compared with The aforementioned esters with acrylic acid and the first internal crosslinking agent can greatly enhance the long-term water absorption capacity and antibacterial properties of the water-absorbent resin.

In the water-absorbent resin composition of the present invention, the polymerization initiator is used to generate free radicals to induce polymerization reaction. The polymerization initiator may include, but is not limited to, a thermal decomposition initiator, a redox initiator, or a combination thereof. In the case where the aforementioned redox initiator is used in combination with the thermal decomposition initiator, the redox initiator first reacts to generate free radicals, and then the free radicals are transferred to the acid group-containing monomer to induce the first stage The free radical polymerization reaction. The radical polymerization reaction in the first stage releases a lot of heat, and the high temperature caused by this heat induces the decomposition of the thermal decomposition initiator, which in turn induces the radical polymerization reaction in the second stage, thereby increasing the completeness of the radical polymerization reaction degree.

In some embodiments, the thermal decomposition initiator may include, but is not limited to, peroxides and/or azo compounds. In some specific examples, the peroxide may include, but is not limited to, peroxides such as hydrogen peroxide, di-tertiary butyl peroxide, amide peroxide, or persulfate (ammonium salt or alkali metal salt). In other specific examples, the azo compound may include, but is not limited to, 2.2'-azobis(2-amidinopropane) dihydrochloride or 2.2'-azobis(N,N-dimethylene iso Butamidine) dihydrochloride and other azo compounds. In other embodiments, the redox initiator may include, but is not limited to, an initiator such as acid sulfite, thiosulfate, ascorbic acid, or ferrous salt.

In some embodiments, based on the weight of the acrylate (that is, the usage amount of the neutralized acid group-containing monomer) is 100% by weight, the usage amount of the polymerization initiator can be 0.001% by weight to 10% by weight, and more Preferably, it is 0.1 weight percent to 5 weight percent. When the amount of polymerization initiator used is 0.001% to 10% by weight, the free radical polymerization reaction rate is moderate, which is in line with economic benefits, and it is easy to control the heat of reaction, so that the degree of polymerization is not easy to be too high and does not form a gel. solid.

In the water-absorbent resin composition of the present invention, the surface cross-linking agent is used to carry out a surface cross-linking reaction on the surface of the hydrogel to form an external cross-linking structure on the surface of the hydrogel to obtain water absorption Resin. The surface crosslinking agent may include, but is not limited to, polyols, polyamines, compounds with at least two epoxy groups, alkylene carbonates, and any combination thereof.

Specific examples of the aforementioned polyols may include, but are not limited to, polyols such as glycerol, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, and propylene glycol. Specific examples of the aforementioned polyamines may include, but are not limited to, polyamines such as ethylenediamine, diethylenediamine, or triethylenediamine. Specific examples of the aforementioned compound having at least two epoxy groups may include, but are not limited to, sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, ethylene glycol diglycidyl ether, and diethylene glycol diglycidyl ether , Glycidyl ethers such as polyethylene glycol diglycidyl ether and diglycerol polyglycidyl ether.

Specific examples of the aforementioned alkylene carbonate may include, but are not limited to, ethylene glycol carbonate, 4-methyl-1,3-dioxolane-2-one, 4,5-dimethyl-1, 3-dioxolane-2-one, 4,4-dimethyl-1,3-dioxolane-2-one, 4-ethyl-1,3-dioxolane Alkane-2-one, 1,3-dioxane-2-one, 4,6-dimethyl-1,3-dioxane-2-one and 1,3-dioxane Heptan-2-one and other compounds.

The usage amount of the hydrogel prepared based on the polymerization reaction is 100 parts by weight, and the usage amount of the surface crosslinking agent is 0.001 parts by weight to 10 parts by weight, and preferably 0.005 parts by weight to 5 parts by weight. When the used amount of the surface crosslinking agent is 0.001 parts by weight to 10 parts by weight, the crosslinking effect of the surface of the water-absorbent resin is obvious, and the water absorption of the water-absorbent resin is improved, thereby improving the performance of the water-absorbent resin.

According to the type of the surface crosslinking agent, the method of adding the surface crosslinking agent may include a direct addition method or an addition method of preparing a crosslinking solution. Among them, the cross-linking solution can be water or a hydrophilic organic solvent, such as methanol, ethanol, propanol, isobutanol, acetone, methyl ether, or ether. In some embodiments, the hydrophilic organic solvent may preferably be methanol or ethanol. As shown in the contents disclosed in US Patent Publication No. 6849665.

Please refer to FIG. 1 below, which is a flowchart of a method for manufacturing a water-absorbent resin according to an embodiment of the present invention. In the method 100, the acid group-containing monomer aqueous solution as described above is provided first, and the neutralization degree of the acid group-containing monomer aqueous solution is 45 mol% to 85 mol%, as shown in operation 110.

Then, the internal crosslinking agent, the polymerization initiator, and the acid group-containing monomer aqueous solution are mixed to carry out a radical polymerization reaction to prepare a hydrogel, as shown in operation 120. The aforementioned internal crosslinking agent includes a first internal crosslinking agent, and the first internal crosslinking agent includes an ester compound having the structure shown in the above formula (I).

The aforementioned free radical polymerization reaction can be carried out in a conventional batch reaction vessel or on a conveyor belt reactor. The hydrogel obtained by the reaction can first be cut into hydrogel particles with a particle size of less than or equal to 20 mm by a chopper, and preferably the particle size of the hydrogel particles is less than or equal to 10 mm. Then, filter.

The aforementioned screening is to screen out hydrogel particles with a fixed particle size of less than or equal to 2.00 mm, preferably the particle size of the hydrogel particles is 0.05 to 1.5 mm. If the particle size of the hydrogel particles is greater than 2.00 mm, the hydrogel particles will be returned to the reactor to be shredded again. When the particle size of the hydrogel particles is less than 0.05mm, it is easy to increase the amount of fine powder of the water-absorbent resin after drying and crushing. When the particle size of the hydrogel particles is greater than 2.00mm, during drying, the hydrogel particles are prone to poor thermal conductivity, which may lead to the disadvantages of high residual monomers and poor performance of other physical properties in the water-absorbent resin. According to the present invention, the narrower the particle size distribution of the hydrogel particles is, the better the physical properties of the hydrogel particles after drying can be achieved, and it is beneficial to control the drying time and temperature.

After the hydrogel particles are screened, they are dried, where the drying temperature can be 100 to 180°C. When the drying temperature is less than 100°C, the drying time is too long and it is not economical. When the drying temperature is greater than 180°C, the internal cross-linking agent will proceed the cross-linking reaction early, and in the subsequent drying process, the excessive cross-linking degree will not effectively remove the residual monomers, so the residual monomers cannot be reduced. The effect.

After drying, the hydrogel particles are crushed and screened to fix the particle size. Then, a coating treatment of the surface crosslinking agent is performed to perform a surface crosslinking reaction on the dried hydrogel particles to prepare a water-absorbent resin, as shown in operation 130. The fixed particle size for screening is 0.06 to 1.00 mm, and preferably 0.10 to 0.85 mm. When the fixed particle size is less than 0.06mm, the finely powdered hydrogel particles increase the dust of the water-absorbent resin product. When the particle size of the hydrogel particles is greater than 1.00 mm, the hydrogel particles slow down the water absorption rate of the water-absorbent resin product. According to the present invention, the particle size distribution of the hydrogel particles is as narrow as possible.

As mentioned above, the dried hydrogel particles have low water content (for example, 100% based on the total weight of the hydrogel particles, and the water content is less than 5%) and have water absorption, so they can also be called As the preliminary water-absorbent resin particles, the water-absorbent resin has a uniform cross-linking and bridging structure inside, and is an insoluble hydrophilic polymer. In order to further improve the absorption rate, colloidal strength, blocking resistance and liquid permeability of the water-absorbent resin, the water-absorbent resin can be selectively subjected to a surface cross-linking process to obtain the water-absorbent resin of the present invention , The surface crosslinking agent used in the surface crosslinking treatment process is as described above, and will not be repeated here.

At present, many patent documents have disclosed the method of surface cross-linking treatment. For example, the surface cross-linking treatment is performed by dispersing preliminary water-absorbing resin and cross-linking agent in an organic solvent (JP-A-56-131608, JP -A-57-44627, JP-A-58-42602, JP-A58-117222); using inorganic powder, the crosslinking agent and the crosslinking agent solution are directly mixed into the water-absorbent resin for surface crosslinking treatment (JP -A-60-163956, JP-A-60-255814); after adding a crosslinking agent, steam treatment (JP-A-1-113406); use organic solvents, water and polyols for surface treatment (JP-A-1-113406) A-1-292004, U.S. Patent Publication No. 6346569); use organic solutions, water, ether and other compounds (JP-A-2-153903). Although these surface cross-linking treatment methods can increase the absorption rate and increase the water absorption rate under pressure, they will cause the undesirable consequences of excessive reduction in retention and reduce the performance of practical applications. However, the surface cross-linking treatment method of the present invention does not cause the above-mentioned disadvantages.

The water-absorbent resin prepared by applying the method for manufacturing the water-absorbent resin of the present invention has an organic acid ester bond. These organic acid ester bonds are derived from the ester bonds of the internal crosslinker structure. After the water-absorbent resin absorbs the liquid, the water-absorbent resin exhibits a weak acidity, and this weak acidity leads to the hydrolysis of the organic acid ester bonds. The breaking of these organic acid ester bonds improves the water absorption capacity of the water-absorbent resin and provides antibacterial properties of the water-absorbent resin.

In addition, if the method for producing the water-absorbent resin of the present invention is kept under an inert gas environment, a water-absorbent resin with better physical properties can be obtained.

In some specific examples, the water-absorbent resin prepared by the present invention can be applied to sanitary products such as diapers (for example, Fluffless (using a large amount of water-absorbent resin at the same time)) or adult diapers. It has both good antibacterial properties and long-term absorption capacity.

In some application examples, the absorbent system of the present invention is molded with water-absorbent resin and hydrophilic fibers to form a sheet-shaped absorbent body. The bottom of the absorbent body is composed of a liquid-impermeable polyethylene (PE) film and the use of liquid-permeable The non-woven fabric is composed of the surface layer; or the water-absorbent resin is fixed on the airlaid and/or non-woven fabric. The pulp fiber is crushed wood pulp, cross-linked cellulose fiber, cotton, wool, vinyl acetate fiber, etc. fiber.

100% by weight based on the weight of the absorber, the content of the water-absorbent resin (core concentration) is equal to or greater than 20% by weight and less than 100% by weight, preferably equal to or greater than 40% by weight and less than 100% by weight, and more Preferably, it is equal to or greater than 50 weight percent and less than 100 weight percent. The use of such a high content of water-absorbent resin in the core concentration can significantly exert the antibacterial and long-term absorption capabilities of the present invention.

Generally speaking, the basis weight (weight per unit area) of the absorbent body of the present invention can be 0.01 g/cm ² to 0.30 g/cm ² , and the thickness of the absorbent body is not more than 30 mm.

The following examples are used to illustrate the application of the present invention, but they are not intended to limit the present invention. Anyone who is familiar with the art can make various changes and modifications without departing from the spirit and scope of the present invention. Preparation of polyethylene glycol propylene ether 3-hydroxy-3-carboxyglutarate

99.6 g (0.2 mol) of polyethylene glycol propylene ether (n=9) (manufactured by Jingqun Company, and the trade name is P3009) was added to 42.3 g (0.22 mol) of 3-hydroxy-3-carboxyl In an aqueous solution of glutaric acid, the temperature is maintained at 120°C and refluxed for 1 hour to proceed the esterification reaction. After cooling to room temperature, 30 mL of saturated sodium bicarbonate aqueous solution was added to quench the reaction. Use a separatory funnel to extract with 30 mL of ethyl acetate, and then use a rotary concentrator to concentrate the organic phase obtained from the extraction to obtain 115 g of polyethylene glycol propylene ether represented by the aforementioned formula (I-2) 3-hydroxy-3-carboxyglutarate. Preparation of water-absorbent resin Example 1

Put 583.2 g of water and 540 g of acrylic acid in a 2000 ml conical flask. After stirring to dissolve, 437.5 g of 48% sodium hydroxide aqueous solution is added dropwise. The dropping time is 2 hours, and the sodium hydroxide and The dropping ratio of acrylic acid is 0.85 to 0.95 while maintaining the temperature at 15°C to 40°C to obtain a sodium acrylate aqueous solution with a monomer concentration of 42 parts by weight, in which 70 mole percent of acrylic acid is partially neutralized to sodium acrylate .

Then add 2.3 g of polyethylene glycol propylene ether 3-hydroxy-3-carboxyglutarate (n=10) to the aforementioned sodium acrylate aqueous solution, and keep the temperature at about 20°C. Then, 0.3 g of hydrogen peroxide, 3.6 g of sodium bisulfite, and 3.6 g of ammonium persulfate were added as a polymerization initiator for radical polymerization. Then, the hydrogel produced after the reaction is shredded by a cutting pulverizer, and hydrogel particles with a diameter equal to and less than 2 mm are screened out according to the particle size.

After drying for 2 hours at 130° C., it was sieved with a fixed particle size screen of 0.1 mm to 0.85 mm to obtain dried hydrogel particles (that is, preliminary water-absorbent resin particles). Then, the test was performed using the evaluation method of the retention force described later, and the results are shown in Table 1.

Prepare a mixed solution of ethylene glycol (manufactured by Sigma-Aldrich) and methanol at a volume ratio of 1.5:0.5, and then add 5 grams of the aforementioned mixed solution to 200 grams of preliminary water-absorbent resin particles, and Heat treatment at a temperature of 150°C for 1 hour. After cooling, the water-absorbent resin of Example 1 is obtained. Then, the test was performed using the following evaluation method, and the results are shown in Table 2 below. Examples 2 to 7 and Comparative Examples 1 to 5

Examples 2 to 7 and Comparative Examples 1 to 5 were prepared using the same method as Example 1. The difference is that the types and usage amounts of the internal crosslinking agents of Examples 2 to 7 and Comparative Examples 1 to 5 are different from those of Example 1. In Example 2, the usage amount of polyethylene glycol propylene ether 3-hydroxy-3-carboxyglutarate (n=10) was 1.2 grams, and the internal crosslinking agent further contained 1.0 grams of polyethylene glycol di Acrylate (n=9) (manufactured by Changxing Chemical Company, and trade name EM226, molecular weight is 523g/mol). Based on the usage amount of the internal crosslinking agent being 100% by weight, the usage amount of polyethylene glycol propylene ether 3-hydroxy-3-carboxyglutarate is 54.5% by weight.

In Example 3, polyethylene glycol allyl ether 2-hydroxysuccinate (n=12) (manufactured by Long Mao Company, and trade name LM6012) was used instead of polyethylene glycol allyl ether 3-hydroxy-3 -Carboxyglutarate (n=10).

In Example 4, polyethylene glycol allyl ether 3-hydroxy-3-carboxyglutarate (n=9) (manufactured by Dorcas and the trade name DK455) was used instead of polyethylene glycol allyl ether 3-hydroxy-3-carboxyglutarate (n=10), the usage amount is 1.2 grams, and the internal crosslinking agent contains 1.0 grams of polyethylene glycol diacrylate (n=9) (by Changxing Chemical Manufactured by the company, and the trade name is EM226, the molecular weight is 523g/mol). Based on the usage amount of the internal crosslinking agent being 100% by weight, the usage amount of polyethylene glycol propylene ether 3-hydroxy-3-carboxyglutarate is 54.5% by weight.

In Example 5, the usage amount of polyethylene glycol propylene ether 3-hydroxy-3-carboxyglutarate (n=10) was 1.2 grams, and the internal crosslinking agent further contained 1.0 grams of polyethylene glycol di Glycidyl ether (n=9) (manufactured by Nagase, and trade name is EX830, molecular weight is 586 g/mol). Based on the usage amount of the internal crosslinking agent being 100% by weight, the usage amount of polyethylene glycol propylene ether 3-hydroxy-3-carboxyglutarate is 54.5% by weight.

In Example 6, the usage amount of polyethylene glycol propylene ether 3-hydroxy-3-carboxyglutarate (n=10) was 1.2 g.

In Example 7, the usage amount of polyethylene glycol propylene ether 3-hydroxy-3-carboxyglutarate (n=10) was 1.1 grams, and the internal crosslinking agent further contained 1.0 grams of polyethylene glycol di Acrylate (n=9) (manufactured by Changxing Chemical Company, and trade name EM226, molecular weight is 523g/mol). Based on the usage amount of the internal crosslinking agent being 100% by weight, the usage amount of polyethylene glycol propylene ether 3-hydroxy-3-carboxyglutarate is 52.4% by weight.

In Comparative Example 1, polyethylene glycol allyl ether (n=10) (manufactured by Jingqun Co., Ltd., and trade name P3009) was used instead of polyethylene glycol allyl ether 3-hydroxy-3-carboxyglutarate (n=10), and the amount used is 2.5 grams.

In Comparative Example 2, polyethylene glycol propylene ether 3-hydroxy-3-carboxyglutarate (n=10) was not used, and only 1.0 g of polyethylene glycol diacrylate (n=9) was used (from Manufactured by Changxing Chemical Co., Ltd., and the trade name is EM226, and the molecular weight is 523g/mol)

In Comparative Example 3, polyethylene glycol propylene ether 3-hydroxy-3-carboxyglutarate (n=10) was not used, and only 1.0 g of polyethylene glycol diglycidyl ether (n=9) was used ( It is manufactured by Nagase Company and has a trade name of EX830 and a molecular weight of 586 g/mol).

In Comparative Example 4, polyethylene glycol diglycidyl ether (n=9) (manufactured by Nagase, with a trade name of EX830 and a molecular weight of 586 g/mol) was used instead of polyethylene glycol propylene ether 3-hydroxy-3 -Carboxyglutarate (n=10), the usage amount is 1.2 g, and the internal crosslinking agent further contains 1.0 g of polyethylene glycol diacrylate (n=9) (manufactured by Changxing Chemical Co., Ltd., and commodity Named EM226, molecular weight is 523g/mol)

In Comparative Example 5, the usage amount of polyethylene glycol propylene ether 3-hydroxy-3-carboxyglutarate (n=10) was 0.3 grams, and the internal crosslinking agent further contained 2.0 grams of polyethylene glycol di Acrylate (n=9) (manufactured by Changxing Chemical Company, and trade name EM226, molecular weight is 523g/mol). Based on the usage amount of the internal crosslinking agent being 100% by weight, the usage amount of polyethylene glycol propylene ether 3-hydroxy-3-carboxyglutarate is 13.0% by weight. The evaluation results of Examples 2 to 7 and Comparative Examples 1 to 5 are shown in Table 1.

Table 1

吸收體之製造 應用例1 Table 1 (continued)

Absorber manufacturing application example 1

First, using an absorbent body forming machine, 10.0g of the water-absorbent resin of Example 1 and 10.0g of ground wood pulp are mixed and molded. The forming mesh is a 400 mesh (38μm) metal mesh and the absorbent body area is 160 cm² ( 8 cm × 20 cm). Then, place the formed absorbent body on top of the PE film, and place the non-woven fabric on the absorbent body. Next, apply a pressure of 18.39kPa (area 160 cm², weight 30 Kg) on it. After applying pressure for 5 minutes, stick around with white glue to obtain the absorbent body of Application Example 1, wherein the absorbent body of Application Example 1 has a basis weight of 0.08 g/cm ² and a thickness of 17 mm. Application examples 2 to 7 and comparative application examples 1 to 5

Application examples 2 to 7 and comparative application examples 1 to 5 were prepared in the same way as application example 1. The difference is that application examples 2 to 7 and comparative application examples 1 to 5 use the water-absorbent resins of examples 2 to 7 and comparative examples 1 to 5 respectively. In addition, the basis weight and thickness of the water-absorbent resins of Application Examples 2 to 7 and Comparative Application Examples 1 to 5 are shown in Table 2, and the evaluation results are also shown in Table 2. Evaluation method

In the following evaluation methods, unless otherwise specified, they are all carried out at room temperature (23±2°C) and relative air humidity of 45±10%. 1. Retention

The retention capacity (Centrifuge Retention Capacity, CRC) is tested in accordance with the measurement method of ERT 441.3 (10) regulated by the European Disposables and Nonwovens Association (EDANA). 2. Core retention

The core retention capacity (Core Centrifuge Retention Capacity, CCRC) is tested in accordance with the ERT 441.3 (10) measurement method specified by EDANA, but the test time is extended to 240 minutes. 3. Water absorption rate under pressure

Absorption Against Pressure (AAP) is tested in accordance with the measurement method of ERT 442.2(5) specified by EDANA. It is to measure the water absorption rate of the water-absorbent resin to a 0.9% sodium chloride aqueous solution under the conditions of a pressure of 4.9kPa and a test time of 60 minutes. The water absorption rate under pressure is preferably greater than 15 g/g, and more preferably 20 to 30 g/g. 4. Free absorption rate

Free Swell Capacity (FSC) is tested in accordance with the ERT 440.3(10) test method specified by EDANA. 5. Core free absorption rate

Core Free Swell Capacity (CFSC) is tested in accordance with the ERT 440.3(10) test method specified by EDANA, but the test time is extended to 240 minutes. 6. Absorption index

其中核心保持力、核心自由吸收倍率、保持力與自由吸收倍率之定義如前所述。 7.殘存單體 Absorption Index (AI) is calculated by the following formula (II):

The definitions of core retention, core free absorption rate, retention force and free absorption rate are as described above. 7. Residual monomer

Residual Monomers (RAA) are tested in accordance with the ERT 410.3(10) test method specified by EDANA. 8. Antibacterial test

The antibacterial test is to analyze the antibacterial ability of water-absorbent resin or absorbent body containing water-absorbent resin against Escherichia coli using the method specified by AATCC100 of the American Textile Chemical Association. When the amount of Escherichia coli in the test group of the water-absorbent resin or absorbent body containing the water-absorbent resin is less than that of the control group, the water-absorbent resin is judged to have antibacterial ability, and the evaluation result is indicated by "○". On the other hand, when the proliferation of Escherichia coli in the test group of water-absorbent resin or absorbent body containing water-absorbent resin is the same as or more than that of the control group, it is judged that the water-absorbent resin does not have antibacterial ability and is indicated by "╳" Evaluation results. 9. The amount of re-seepage

The test process of Rewet (dryness) is to place a weight of 4.8kPa (area 160cm² and weight 7.8Kg) on the absorbent body for the test, and apply the weight evenly on the absorbent body for the test. body. Then, synthetic urine (according to the Jayco synthetic urine described in U.S. Patent Publication No. 20040106745) was added three times at the central point, and added to the absorber at a frequency of 30 minutes each time. The total amount of synthetic urine Is 180 ml. After adding the synthetic urine, and after 30 minutes, remove the heavy objects above the absorbent body for the test, and place a filter paper (8 cm x 20 cm) with a pre-measured total weight (W1(g)) on the absorbent body for the test 30 sheets, and then immediately put a 4.8kPa weight on the absorbent body for testing for 5 minutes to allow the filter paper to absorb the liquid that has permeated back, and then measure the weight (W2(g)) of 30 sheets of filter paper. The amount of liquid reperfusion (g) is the weight value of W2 minus W1. When the amount of re-penetration is lower, it means that the dryness of the water-absorbent resin is better.

Table 2

Please refer to Table 1. According to the results of core free absorption rate, absorption index and antibacterial test, compared with Comparative Example 1 without the first internal crosslinking agent and Comparative Examples 2 to 4 with only the second internal crosslinking agent, The water-absorbent resin of each embodiment has a higher core free absorption rate and absorption index, and better antibacterial properties. In addition, in Comparative Example 5, based on the usage amount of the internal crosslinking agent being 100% by weight, the usage amount of the first internal crosslinking agent was 13.0% by weight, because Comparative Example 5 used too low the first internal crosslinking agent ( Less than 20% by weight), so compared with the examples, the water-absorbent resin of Comparative Example 5 has a lower core free absorption rate and absorption index and poor antibacterial properties. This shows that with a specific structure and specific usage amount of the first internal cross-linking agent, the water-absorbent resin prepared therefrom has good antibacterial properties and long-term absorption capacity.

Please refer to Table 2. According to the results of the antibacterial test, compared to Comparative Application Example 1 without using the first internal crosslinking agent and Comparative Application Examples 2 to 4 using only the second internal crosslinking agent, the absorber of each application example Has better antibacterial properties. In addition, in Comparative Application Example 5, similar to the foregoing, since Comparative Application Example 5 uses too low a first internal crosslinking agent, the absorbent body of Comparative Application Example 5 has poor antibacterial properties compared to each application example. . This shows that with a specific structure and a specific usage amount of the first internal crosslinking agent, the absorbent body made therefrom has good antibacterial properties.

Applying the water-absorbent resin composition and the method of manufacturing water-absorbent resin of the present invention, the water-absorbent resin obtained has good antibacterial properties and long-term properties by using a specific structure and a specific amount of the first internal crosslinking agent. Effective absorptive capacity.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field of the present invention can make various changes and modifications without departing from the spirit and scope of the present invention. Retouching, therefore, the scope of protection of the present invention shall be subject to the scope of the attached patent application.

100: method 110, 120, 130: Operation

In order to have a more complete understanding of the embodiments of the present invention and its advantages, please refer to the following description and the corresponding drawings. It must be emphasized that the various features are not drawn to scale and are for illustration purposes only. The contents of the relevant diagrams are described as follows: [Fig. 1] is a flowchart showing a method for manufacturing a water-absorbent resin according to an embodiment of the present invention.

100: method

110, 120, 130: Operation

Claims (10)

A water-absorbent resin composition, comprising: an acid group-containing monomer aqueous solution, wherein a neutralization degree of the acid group-containing monomer aqueous solution is 45 mol% to 85 mol%; an internal crosslinking agent, including a first An internal crosslinking agent, wherein the first internal crosslinking agent comprises an ester compound having a structure as shown in formula (I):

(I) Where X represents a linear or branched alkenyl group with carbon number of 3 to 5, and the end of X away from Y is a double bond structure; n represents 8 to 15; plural Ys each independently represent a glycol group Or a propylene glycol group, and the oxygen atom of the ethylene glycol group and the propylene glycol group is bonded to X; Z represents a substituted saturated linear carboxyl group with 3 to 7 carbon atoms, and one end of Z away from the carbon atom is a carboxyl structure. The substituent of the saturated linear carboxyl group includes a hydroxyl group, and the number of the hydroxyl group is 1 to 3; a polymerization initiator; and a surface crosslinking agent. The water-absorbent resin composition according to claim 1, wherein the acid group-containing monomer aqueous solution contains a neutralized acid group-containing monomer, and the usage amount based on one of the acid group-containing monomer aqueous solution is 100 parts by weight A usage amount of the neutralized acid group-containing monomer is 20 parts by weight to 55 parts by weight. The water-absorbent resin composition according to claim 2, wherein based on the total usage amount of the neutralized acid group-containing monomer, the internal crosslinking agent, and the polymerization initiator is 100 parts by weight, the internal crosslinking A usage amount of the agent is 0.001 parts by weight to 5 parts by weight. The water-absorbent resin composition according to claim 1, wherein the internal crosslinking agent further comprises a second internal crosslinking agent, and the second internal crosslinking agent is selected from the group consisting of amines having acrylic groups and acrylic resins. The group of esters, ethers with at least two ethylene oxides, and any combination thereof. The water-absorbent resin composition according to claim 1 or 4, wherein a usage amount of the first internal crosslinking agent is not less than 20% by weight based on 100 weight percent of the internal crosslinking agent. A method for manufacturing a water-absorbent resin, comprising: providing an acid group-containing monomer aqueous solution, wherein the acid group-containing monomer aqueous solution has a neutralization degree of 45 mol% to 85 mol%; mixing an internal crosslinking agent, A polymerization initiator and the acid group-containing monomer aqueous solution undergo a radical polymerization reaction to prepare a hydrogel, wherein the internal crosslinking agent includes a first internal crosslinking agent, and the first internal crosslinking agent The internal crosslinking agent includes an ester compound having a structure as shown in formula (I):

(I) Where X represents a linear or branched alkenyl group with carbon number of 3 to 5, and the end of X away from Y is a double bond structure; n represents 8 to 15; plural Ys each independently represent a glycol group Or a propylene glycol group, and the oxygen atom of the ethylene glycol group and the propylene glycol group is bonded to X; Z represents a substituted saturated linear carboxyl group with 3 to 7 carbon atoms, and one end of Z away from the carbon atom is a carboxyl structure. The substituent of the saturated linear carboxyl group includes a hydroxyl group, and the number of the hydroxyl group is 1 to 3; and a surface crosslinking agent is used to perform a surface crosslinking reaction on the hydrogel to prepare the water-absorbent resin. The method for producing a water-absorbent resin according to claim 6, wherein the neutralized acid group-containing monomer, the internal crosslinking agent, and the polymerization initiator contained in the acid group-containing monomer aqueous solution are combined The usage amount is 100 parts by weight, and a usage amount of the internal crosslinking agent is 0.001 parts by weight to 5 parts by weight. The method for producing a water-absorbent resin according to claim 6, wherein the internal crosslinking agent further comprises a second internal crosslinking agent, and the second internal crosslinking agent is selected from amines having acrylic groups, Acrylic esters, ethers with at least two ethylene oxides, and any combination thereof. The method for producing a water-absorbent resin according to claim 8, wherein a usage amount of the first internal crosslinking agent is not less than 20% by weight based on a usage amount of the internal crosslinking agent being 100% by weight. A water-absorbent resin prepared by the method for producing a water-absorbent resin according to any one of claims 6 to 9, wherein the water-absorbent resin has an organic acid ester bond.

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