[Technology]
Mutual citations and related application (s)
This application claims the benefit of priority based on the December 27 issue of Korea Patent Application No. 10-2016-0180348 and No. 4, 2017 May 19, 2016 Date of Korea Patent Application No. 10-20Γ7-0050399 call it, and that Korea Patent everything described in the literature of the application are included as part of the specification.
The present invention relates to a water-absorbent resin and a method of manufacturing and excellent in absorbing performance.

[Background Art]

The superabsorbent resin (Super Absorbent Polymer, SAP) is a synthetic polymeric material having the ability to absorb 500 to about a thousand times the water of its own weight, each developer SAM (Super Absorbency Mater i al), AGM ( Absorbent Gel Mater i al), etc. are each named with a different name. Superabsorbent polymer as described above is to begin commercialization of physiological equipment, currently freshness at Children diapers, etc. sanitary ware in addition to horticultural soil repair filler, engineering, construction index material, nursery sheets, food for distribution areas first, and It has been widely used for a material such as a poultice.

In most cases, these super-absorbent resins are widely used in the field of sanitary materials such as diapers and sanitary napkins. Within such hygienic material, the superabsorbent resin is usually to be included in a state spread in the pulp. However, the recent years, and more, and efforts continue dwago to provide a sanitary material such as a thin diaper, the amount of pilpeu increased or as the part, and further the pulp is not used at all so-called pulp-less (pulpless) diapers of the proceeds are being developed actively.

In this way, decrease the content of pulp or, for sanitary material of pulp is not used, relatively high water-absorbent resin is contained in the high ratio, and such is inevitably included in a multi-layer water-absorbent resin particles in the sanitary material. So that the whole contained in a multi-layer in order to absorb a liquid such as water-absorbent resin particles efficiently in the urine of all, the high as well as the required water-absorbent resin exhibit high absorption capability and the absorption rate by default, and more. The improved barrel-component there must point. That is, the super-absorbent resin is improved barrel must exhibit liquid, the urine, such as liquid and the first superabsorbent polymer particles of the surface layer which contacts to and absorbed and rapidly pass through the remaining liquid, this remaining liquid super-absorbent resin of the back layer the particles are able to quickly and effectively absorbed.

Accordingly, recently improved, but he is trying to develop a water-absorbent resin made of a multi-faceted, a situation that does not yet fully meet these technical requirements.

[Contents of the present invention;

- to solve problems;

The present invention is to provide an excellent super-absorbent resin and a method of manufacturing the absorbing performance.

[Solving means of a problem]

In order to achieve the foregoing object, the present invention provides a super-absorbent resin of the following:

Water-soluble ethylenic base resin including a first cross-linked polymer of an unsaturated monomer having a powder at least partially neutralizing the acid; And

A super-absorbent resin to the base resin is formed on the powder and the first cross-linked polymer comprises a cross-linked surface layer and a second cross-linked polymer cross-linking the surface cross-linking agent is added to the medium,

And a 0.3 psi AUL-gel 15 bun at least 13 g / g,

Pressure absorption capacity (AUL) is more than 18 g / g, and eu

And a gel bed permeability (GBP) of 30 Darcy (darcy) above,

The absorption rate is not more than 45 seconds, the superabsorbent polymer measured according to the measurement method Vortex.

Further, the present invention provides a super-absorbent resin of the following: Water-soluble ethylenic base resin including a first cross-linked polymer of an unsaturated monomer having a powder at least partially neutralizing the acid; And

A super-absorbent resin to the first cross-linked polymer is formed on the base resin powder, a cross-linked layer includes a surface including a second cross-linked polymer cross-linking a surface cross-linking agent is added to the medium,

From 15 minutes gel-AUL is at least 13 g / g of 0.3 ps i,

And a gel bed permeability (GBP) of 30 Darcy (darcy) above,

The absorption rate is not more than 45 seconds, the superabsorbent polymer measured according to the measurement method Vortex.

And there is a way to increase the surface area of ​​the superabsorbent resin is studied, in order to improve the absorbing performance of the water absorbent resin. And to widen the surface area of ​​the water-absorbent resin, but a method of using a polymerization a blowing agent of the water-soluble ethylenically unsaturated monomers is known, the use of excessive foaming agent is caused a problem with the gel strength is low or the density distribution and storage lower the superabsorbent polymer can. Alternatively, the problem of when to grant excessive shearing force upon this, but the pulverized how to reduce the size of the particles through the coarse ground particles of the hydrogel polymer and degrade the physical properties of the water absorbent resin or difficult to process the pulverized have.

In the present invention, by using a surface active agent with the polymerization when the blowing agent of the water-soluble ethylenically unsaturated monomer, and prevent the lower the gel strength or the density is lowered to a uniform foaming, and Division of hydrogel polymer pulverized as described below when thus the final product, and improves the absorption performance of the water-absorbent resin due to the surfactant by reducing crushing than that normally produced particle size.

Hereinafter the present invention will be described in detail.

Superabsorbent polymer

Water-soluble ethylenically unsaturated monomer constituting the cross-linked polymer system 1 may be any of the monomers conventionally used in the manufacture of a superabsorbent polymer. Non-limiting examples of the water-soluble ethylenically unsaturated monomer may be a compound represented by the following general formula (1):

Formula 1

In the formula 1,

Ri is an alkyl group of 2 to 5 carbon atoms including an unsaturated bond,

M 1 is a hydrogen atom, or one divalent metal, an ammonium group or an organic amine salt.

Preferably, the monomer may be at least one member selected from acrylic acid, methacrylic acid, and monovalent metal salts of these acids, the group consisting of a divalent metal salt, ammonium salt and organic amine salt. Thus, when using an acrylic acid or a salt of a water-soluble ethylenically unsaturated monomer advantageously superabsorbent improved to obtain a water-absorbent resin. In addition to the monomers maleic anhydride, fumaric acid, crotonic acid, itaconic acid, one ethanesulfonic acid, 2-meth yl-acryloyl ethane sulfonic acid, 2- (meth) propanoic acid or 2- (2-meth-acryloyl acrylic ) acrylamide-2-methylpropanesulfonic acid, (meth) acrylamide, N- substituted (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, polyethylene during meteuk glycol

(Meth) acrylate, polyethylene glycol (meth) acrylate, (Ν, Ν) - and the like dimethylaminopropyl (meth) acrylamide may be used - dimethylaminoethyl (meth) acrylate, (Ν, Ν).

Here, the water-soluble ethylenically unsaturated monomer having an acidic group, may be at least partially neutralizing the acid groups. Preferably it is used which is partially neutralized the monomers with an alkali substance such as sodium hydroxide, potassium hydroxide, ammonium hydroxide.

In this case, the neutralization degree of the monomer may be 40 to 95 mol ¾>, or 40 to 80 mole ¾>, or 45 to 75 mol%. Range of the degree of neutralization may be different depending on the final physical properties, the degree of neutralization precipitation is too high, the neutralized monomer may be difficult to polymerization proceeds smoothly, whereas if the degree of neutralization is too low, as well as decrease the absorption capacity of the polymer greatly handling can exhibit properties such as hard rubber.

To the second cross-linked polymer is that the surface of the base resin powder were added to the surface cross-linking agent cross-linked to a parameter, the surface cross-linking agent and surface cross-linking method will be described later.

^ Hand, super-absorbent resin according to the present invention is at least 13 g / 15 g gel-bun of AUL 0.3 psi. 15 minutes is the AUL-gel, a reduction in samurai saline 1.5 g 1 primary swelling and with respect to the water absorbent resin 0. 16 g, physiological saline a superabsorbent polymer to absorb under a 0.3 psi pressure for 15 minutes in the 0.3 psi ( means an amount of 0.9 wt% NaCl), which high and the water-absorbent resin refers to the ability to continue to absorb large amounts of water in a short time under a 0.3 psi pressure after the swollen primary in samurai reduction eu specific measurement method thereof, It is embodied in more, the following examples.

Preferably, the super-absorbent resin according to the present invention is 15 minutes gel-AUL 0.3 psi of 13.5 - a g / g or more, 14.0 g / g or more, 14.5 g / g or more, or 15.0 g / g or more. Further, Because the value is high The higher the value, but is limited in the practical upper limit, 25.0 g / g or less, 24.0 g / g or less, 23.0 g / g or less, 22.0 g / g or less, 21.0 g / g for example or less, or 20.0 g / g or less.

In addition, the super-absorbent resin according to the present invention, 0.6 psi and 15 minutes gel-AUL is at least 12 g / g. 15 minutes of gel-AUL 0.6 psi is a, the same 15 minutes gel-AUL 0.3 psi of the above, instead of just 0.3 psi as measured under 0.6 ps i pressure. In addition, the excellent values ​​because the higher the value, the actual

Although there is no upper limit of a 25.0 g / g or less, 24.0 g / g or less, 23.0 g / g or less, 22.0 g / g or less, 21.0 g / g or less, or 20.0 g / g or less, for example.

In addition, the super-absorbent resin according to the present invention is an AUL at least 18 g / g. The AUL is to mean the amount of brine absorbed for an hour under a 0.9 psi pressure, which means that the total amount of water in a water absorbent resin can absorb. Specific measuring method thereof is embodied in more, the following Examples.

Preferably, the AUL is 18. 1 g / g or higher, 18.2 g / g or more, 18.3 g / g or more, 18.4 g / g or more, or 18.5 g / g or more. Further, Because the value is high The higher the value, but is limited in the practical upper limit, 25.0 g / g or less, 24.0 g / g or less, 23.0 g / g or less, 22.0 g / g or less, 21.0 g / g for example or less, or 20.0 g / g or less.

In addition, the super-absorbent resin according to the invention is at least 30 Darcy (darcy) gel bed permeability (GBP). The GBP is said to mean a flow of absorbed water to the water-absorbent resin, which means a high capacity of absorbing moisture in the water-absorbent resin to be quickly transmitted to the other super-absorbent resin. Specific measuring method thereof is embodied in more, the following Examples.

Preferably, the GBP is at least 35 Darcy, at least 40 Darcy, or at least 45 Darcy. In addition, the upper limit of GBP is less than 65 Darcy, 60 Darcy or less, or less than 55 Darcy.

In addition, the super-absorbent resin according to the present invention is that the absorption rate measured in accordance with the Vortex method of measuring less than 45 seconds. The absorption rate is high when sikyeoteul in physiological saline was added to stirring water-absorbent resin, as meaning that the missing time swirl (vortex) of the fluid by the fast absorption, the high mean faster absorption capacity of absorbent resin. Specific measuring method thereof is embodied in more, the following Examples. The lower limit of the absorption rate is, as an example at least 26 seconds, at least 27 seconds, or more than 28 seconds.

In addition, the super-absorbent resin according to the present invention, the centrifugation beam SAT (CRC) for half an hour for the physiological saline (0.9 wt% aqueous sodium chloride solution) is at least 29 g / g. The centrifugation beam SAT, means the ability of a superabsorbent resin as pictures of absorbed moisture. Specific measuring method thereof is embodied in more, the following Examples.

Preferably, the centrifugation beam SAT is 29.5 g / g or more, and 30.0 g / g or more, or at least 30.5 g / g, 35 g / g or less, 34 g / g or less, or 33 g / g or less.

In addition, preferably, the high water-absorbent resin according to the present invention is an average particle diameter of 300 to 600. In addition, preferably, a superabsorbent polymer wherein said a particle diameter of the water-absorbent resin is 300 to 600 according to the invention to 45 to 85% by weight eu addition, preferably, in which the particle size of the water-absorbent resin is 300 im or less superabsorbent a resin at least 15% by weight.

Method for producing a superabsorbent resin

The present invention provides a method comprising the steps of, by the production process of the above-mentioned super-absorbent resin:

In the presence of an internal cross-linking agent, a blowing agent and a surfactant, by cross-linking polymerization of the water-soluble ethylenically unsaturated monomer having at least partially neutralized acid, comprising the steps of forming a hydrogel polymer 1 comprises a cross-linked polymer (phase 1);

The method comprising the average particle diameter to tighten the hydrogel polymer pulverized to prepare a hydrogel polymer 隱 1.0 to 2.0 隱 (step 2);

And drying and pulverizing the hydrogel polymer to prepare a base resin powder (Step 3); And

In the presence of a surface crosslinking agent, a method of manufacturing a super-absorbent resin, including a step (step 4) for producing a water-absorbent resin particles and the surface cross-linked by heating a base resin powder

Hereinafter, the manufacturing method in detail for each step.

(Step 1)

The step 1 is a step of forming a hydrogel polymer, a step of crosslinking polymerization of a monomer composition comprising a water-soluble ethylenically unsaturated monomer having an internal cross-linking agent, a blowing agent, a surfactant, and an at least partially neutralized acid.

In this case the same as the water-soluble ethylenically unsaturated monomers mentioned above. Further, the monomer composition of the concentration of the water-soluble ethylenically unsaturated monomer may be may be appropriately adjusted in consideration of the polymerization time and the reaction conditions, preferably from 20 to 90% by weight, or 40 to 65 weight ¾. These concentration ranges, yet eliminate the need to remove the unreacted monomers after polymerization by using a gel banung effect phenomenon in banung polymerization of the high concentration solution, it may be advantageous to control the grinding efficiency in the grinding of the polymer, which will be described later. However, it is possible that when the concentration of the monomer is too low, a drop in yield of the water-absorbent resin. On the other hand, the concentration of the monomer may lead to a too high step surface portion is such as precipitation polymerization or the function falling crushed during grinding efficiency of the gel-like polymer of the monomer problem, and can be the physical properties of the super-absorbent resin decreases.

Further, the internal crosslinking agent may also be used if any compound which allows the introduction of a cross-linking polymerization of the water-soluble ethylenically unsaturated monomer. Non-limiting examples, the internal cross-linking agent is Ν, Ν '- methylenebisacrylamide, teurimetilreul tri (meth) acrylate, ethylene glycol di (meth) acrylate, polyethylene glycol (meth) acrylate, propylene glycol di (meth ) acrylate, polypropylene glycol (meth) acrylate, butane diol di (meth) acrylate, butylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, acid di (meth) acrylate, triethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, di-penta the EPO Li pentaacrylate, glycerin tri (meth) acrylate, a penta EPO tetraacrylate, triarylamine, ethylene glycol Glycidyl it not intended to ether, propylene glycol, glycerin, or a multi-functional crosslinking agent such as ethylene carbonate may be used in combination than alone, or two, limited.

These internal cross-linking agent may be added at a concentration of about 0.001 to 1% by weight relative to the monomer composition. That is, when the concentration of the internal cross-linking agent is too low, the absorption rate of the resin is not lowered is preferable because the gel strength may be weakened. In contrast, the absorption capacity of the resin when the concentration of the internal cross-linking agent is too high, can be so low as not preferred absorber.

Further, in the above Step 1, it can be included in the polymerization initiator which is commonly used in the production of superabsorbent polymer. Non-limiting examples, the polymerization initiator and the like, a thermal polymerization initiator or a photopolymerization initiator may be used in accordance with the polymerization method, in particular, it may be used as thermal polymerization initiators. However, even in light of the polymerization process, it occurs a certain amount of heat due to ultraviolet radiation, and also a certain amount of heat generated with the progress of polymerization heat generation banong banung, may be included to add a thermal polymerization initiator.

The thermal polymerization initiator is a persulfate-based initiator, an azo type there is going to 1, hydrogen peroxide, and at least one compound selected from the group consisting of ascorbic acid can be provided. Specifically, the persulfate-based initiator and sodium sulfate (Sodium persul fate; Ν & 2¾0 8 ), potassium persulfate (Potassium persul fate; K 2 S 2 0 8 ), ammonium persulfate (Ammonium persul fate; (NH 4 ) 2 S 2 0 8 ) and the like are exemplified. Further, azo (Azo) based initiators include 2,2-azo bis- (2

Amidinopropane) dihydrochloride (2,2-azobis (2-amidinopropane) di hydrochloride), 2, 2- azobis - (Ν, Ν- dimethylene) isobutoxy Thira Mai Dean dihydrochloride (2, 2-azob i s- (Ν, Nd i me t hy 1 ene) is obut yr am idi ne di hydrochloride), 2- (carbamoyl-azo) isobutyronitrile (2- (carbamoy lazo) i sobutyl onitril), 2,2- azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride (2,2-azobis [2- (2-imidazol in-2-yl) propane] dihydrochlor ide), 4,4- azobis 一 the like are exemplified (4-cyano ballet rigs acid) (4,4- & 20 3- (4 ^ 0 ¥ 31 ^ acid)). Than it is disclosed in various heat Odia book, "For the polymerization initiator Principle of Polymerization (Wiley, 1981 year)," page 203, and can refer to it.

The photo polymerization initiators include, for example, benzoin ethers (benzoin ether), dialkyl acetophenones (dialkyl acetophenone), hydroxyl-alkyl ketones (hydroxyl alkylketone), phenyl glyoxylic rate (phenyl glyoxylate), benzyl dimethyl ketal ( there is at least one compound selected from the group consisting of amino-ketone (α-aminoketone) may be used - Benzyl Dimethyl Ketal), acylphosphine (acyl phosphine) and alpha. Specific examples of the acylphosphine of that, commercial lucirin TP0, i.e., 2,4,6-trimethyl-to-benzoyl-trimethyl-phosphine oxide may be used (2,4,6-trimethyl-benzoyl-trimethyl phosphine oxide) . Wider range of light for the polymerization initiator Reinhold Schwa lm book,: is disclosed in page 115 of "UV Coatings Basics, Recent Developments and New Ap 1 i cat i on (El sevi er 2007 year)," and may refer to them.

The polymerization initiator may be added at a concentration of about 0.001 to 1% by weight relative to the monomer composition. That is, when the concentration of the polymerization initiator is too low and may slow the rate of polymerization is not preferable because it can be residual monomers are extracted in a large amount in the final product. On the other hand, it is not preferable because the resin properties such as the concentration of the polymerization initiator increases the concentration of component for the number becomes the polymer chains that make up the network shorter is higher than the above range, absorption capacity under pressure that is lowered can be reduced.

In addition, the monomer composition comprises a foaming agent. The foaming agent is foamed up and the polymerization serves to increase the surface area by forming the pores hydrogel polymer increases. The blowing agent may be used a carbonate, for example sodium ratio ^! " Carbonate (sodium bi carbonate), sodium Gabor carbonate (sodium carbonate), potassium bicarbonate (potassium bi carbonate), Porta thoracic carbonate (potassium carbonate), calcium bicarbonate (calcium bi carbonate), calcium carbonate (calcium bicarbonate), magnesium ratio 71 "carbonate (magnesiumbicarbonate) or:" may be used magnesium 7] · carbonate (magnes ium carbonate).

In addition, the blowing agent is preferably used in more than 1500 ppmw contrast weight of the water-soluble ethylenically unsaturated monomer. When the amount of the foaming agent exceeds 1500 pp 丽 has a high porosity becomes too much gel strength of the water-absorbent resin drops decreases the density can lead to problems with the distribution and storage. In addition, the blowing agent is preferably used as the water-soluble ethylenically unsaturated monomer, based on the weight of more than 500 ppmw, or at least 1000 ppmw.

In addition, the monomer composition comprises a surfactant. The surfactant to induce the uniform distribution of the blowing agent is prevented from being lowered the gel strength or the density is lowered at a uniform foam during foaming. Also it causes the grain size to be smaller than normal due to the production of surface active agent when pulverized hydrogel polymer that will be described later in step 2 and grinding a final product, enhance the absorption performance of the water absorbent resin.

To the surfactant is an anionic surfactant used ■ is preferred. Specifically, the surfactant S0. 3 - to be, containing the anion may be a compound represented by the formula (2).

[Formula 2]

-S03Na

In Formula 2,

R is alkyl having 8 to 16.

Also, the surfactant is preferably used in weight than compared to the water-soluble ethylenically unsaturated monomer 300 ppmw. If the amount of the surface active agent exceeds 300 ppmw, which is not preferable it becomes the content of the surfactant increases the super-absorbent resin. Also, the surfactant is preferably used as the water-soluble ethylenically unsaturated monomer, based on the weight of more than 100 ppmw, or at least 150 ppmw.

In addition, the monomer composition has an additive such as a thickener, a plasticizer, a preservation stabilizer, an antioxidant can be further included if necessary.

Then, this monomer composition can be a raw material such as the aforementioned monomers prepared in the form of a solution dissolved in a solvent. At this time, a usable solvent as long as it can dissolve the above-described raw materials may be used without any limitation in its configuration. For example, as the solvent is water, ethanol, ethylene glycol, diethylene glycol, triethylene glycol, 1,4-butanediol, propylene glycol, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate , methyl ethyl ketone, acetone, methyl amyl ketone, cyclo hex rice, cyclopentanone, diethylene glycol monomethyl ether, diethylene glycol ethyl ether, the toluene, xylene, cellosolve a lactone, a carboxylic non-butyronitrile, methyl cells acetate , it may be used Ν, Ν- dimethylacetamide, or a compound such as common.

And, forming a hydrogel polymer by polymerization of the monomer composition can be carried out in a conventional polymerization process, the process is not particularly limited. Non-limiting examples, the polymerization process is divided into large thermal polymerization and photo polymerization according to the type of the polymerization energy source, if the progress of the thermal polymerization may take place in half unggi with axis agitation, such as a kneader (kneader), light when proceeding the polymerization it may take place in a half unggi provided with a movable conveyor belt.

For example, it is possible to half unggi such as the stirring shaft provided with a kneader to obtain a gel-like polymer by charging function, and a thermal polymerization by supplying hot air to this heating, the reactor or the monomer composition. At this time, depending on the form of a stirring shaft provided with a function to the reactor the gel polymer to be discharged to the outlet half unggi may be obtained with particles of a few millimeters to several centimeters. Specifically, the gel-like polymer obtained is a function may be obtained in various forms depending on the concentration and the injection rate of the monomer composition to be injected, it is normal (weight average) grain size of 2 to 50 mm function gel polymer can be obtained.

And, one another example, if the progress of photopolymerization of the monomer composition in the conveyor belt provided with a movable half unggi has a function gel polymer in the form of a sheet can be obtained. That case that there the thickness of the sheet may vary depending on the concentration and the injection rate of the monomer composition to be injected, to ensure the production speed, but that the entire sheet can be uniformly polymerized, usually adjusted to a thickness of 0.5 to 5 cm desirable.

In this case usually the water content of the hydrogel polymer obtained by the same method

40 to 80% by weight may be. On the other hand, the throughout the specification, "water content" "refers to a value on the weight of the hydrogel polymer in an amount of water which accounts for the entire hydrogel polymer weight minus the weight of the dry polymer. Specifically, through infrared heating by measuring the weight decrease due to evaporation of water in the polymer in the process of up and dried the temperature of the polymer is defined as a calculated value. in this case, drying conditions at room temperature, about 180 ° 180 after raising the temperature up to C ° for holding at C the total drying time in such a manner is set to 20 minutes, including the silver is rise of 5 minutes to measure the water content.

(Step 2)

The step 2 is a step for preparing the small average particle size function gel polymer was pulverized crude a hydrogel polymer produced in the first step.

In particular, the present invention can be made using a surface active agent in the manufacture hydrogel polymer, and thus usually ground to a smaller particle size of 1.0 mm to 2.0 mm than the production of the hydrogel polymer in accordance, as described above. The need to excessive shear force process difficult and also the physical properties of the super-absorbent resin is lowered in order to crush the hydrogel polymer without the surface active agent as in the present invention in the above-described particle size. However, in the present invention and can be crushed to a smaller particle size because of the use of the surface active agent, and becomes accordingly wider the surface area of ​​the water absorbent resin may have an excellent absorption capacity.

Grinder used for the coarse ground particles are limited in configuration, but, specifically, a vertical cutter (Vertical pulverizer), turbo cutter (Turbo cutter), a turbo grinder (Turbo grinder), rotary cutting mill (Rotary cutter mill) , cutting mill (cutter mill), disc mill (disc mill), a piece crusher (Shred crusher), crusher (crusher), the chopper (chopper) and one-plate type cutting machine one selected from the grinding machine the group consisting of (disc cutter) It can include, but are not limited to the above example.

Further, it is possible to perform a plurality of coarse ground particles of the circuit according to the particle size for the efficiency of the pulverized. For example, it may be pulverized first tighten the hydrogel polymer to the average particle size of about 10 咖 and having them re secondary pulverized to average particle size of about 5 mm and then pulverized three perilla in the above-described particle size.

(Step 3)

The step 3 is a step of drying and pulverizing a hydrogel polymer prepared in Step 2, prepare the surface cross-linking to be described later.

The drying temperature is 50 to 250 ° may be C. The dry silver is 50 ° C

, And that the drying time is too longer and forming end, and the possibility that the physical properties of the water absorbent resin decreases, the drying temperature is 250 less than ° , and if it exceeds C, the drying only over the polymer surface and may result in the differential, the final forming and that there is a fear that the physical properties of the water absorbent resin decreases. More preferably, the drying is 150 to 200 ° can be carried out at a temperature of C, more preferably at a temperature of 160 to 19CTC. On the other hand, drying time is in consideration of process efficiency, it may proceed for 20 minutes to 15 hours, but are not limited to this.

As long as it is usually used in the drying step can be used are selected, without limitation of its construction. Specifically, a method such as hot air supply, infrared irradiation, microwave irradiation, or the ultraviolet irradiation may be carried out a drying step. The water content after the drying phase, such polymers can be from 0.05 to 10 parts by ¾.

Next, the steps of crushing the dried polymer obtained through this drying steps.

After the grinding step the resulting polymer powder may be a particle diameter of 150 to 850. In this mill it is used to crush the particle size of the concrete, a ball mill (ball mill), pin mill (pin mill), a hammer mill (ha 誦 er mill), screw mill (screw mill), wheat (roll mill) to , but can use a disc mill, etc. (disc mill) or the jog mill (jog mill), but it is not limited to the above example.

And, after this step, such as grinding , to that end and commercialized to manage the physical properties of the water-absorbent resin powder, it may be subjected to a separate step of classifying the obtained polymer powder according to the particle diameter after grinding. Preferably the particle size is classified to 150 to 850, the polymer can be commercialized through this surface cross-linking step to be described later banung only the polymer powder of the same particle size.

(Step 4)

The step 4 is a step of crosslinking a surface of a base resin prepared as described in Step 3, in the presence of a surface cross-linking solution containing the surface crosslinking agent, by surface cross-linked by heating a base resin powder and forming a water-absorbent resin particles a step.

Here, the type of the surface cross-linking agent contained in the surface cross-linking solution is not particularly limited. Non-limiting examples, the surface cross-linking agent is ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glyceryl polyglycidyl ether, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, ethylene carbonate, ethylene glycol, diethylene glycol, propylene glycol, triethylene glycol, tetraethylene glycol, propane diol, dipropylene glycol, polypropylene glycol, glycerin, polyglycerin, butane diol, heptane diol, nucleic dayieul teurimetilreul propane , penta EPO recalled, it may be a sorbitan ratio, at least one compound selected from calcium hydroxide, magnesium hydroxide, aluminum hydroxide, iron hydroxide, calcium chloride, magnesium chloride, aluminum chloride, and the group consisting of iron chloride.

At this time, the amount of the surface cross-linking agent may be appropriately adjusted depending on its type or banung conditions, and preferably can be adjusted as part of 0.001 to 5 parts by weight per 100 parts by weight of the base resin. When the amount of the surface cross-linking agent is too low, the surface cross-linking can not be properly introduced, the physical properties of the final superabsorbent polymer may be lowered. Conversely the surface cross-linking agent is used in an excessive amount is not high due to excessive surface cross-linking banung preferable because the absorption capacity of the water-absorbent resin can be rather low.

Further, the surface cross-linking liquid is water, ethanol, ethylene glycol, diethylene glycol, triethylene glycol, 1,4-butanediol, propylene glycol, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, methyl ethyl ketone, acetone, cellosolve, methyl amyl ketone, cyclo hex rice, cyclopentanone, diethylene glycol monomethyl ether, diethylene glycol ethyl ether, frame toluene, xylene, lactone, butyl acid rain, methyl cells acetate and Ν, it may further include one or more solvents selected from the group consisting of Ν- dimethylacetamide. The solvent is 100, the base resin , can be included as part of 0.5 to 10 parts by weight based on parts by weight.

Further, the surface cross-linking solution may further comprise a thickening agent. This cross-linking under the thickening agent present in adding the surface of the base resin powder can minimize the physical property degradation even after grinding. Specifically, the thickener in may be used at least one selected of the polysaccharide and a hydroxy-containing polymer. The polysaccharides include the like can be used agarose-based thickener with gum-based thickening agents and saelreul. Examples of the Sword series thickener, xanthan gum (xanthan gum), Arabic gums (arabic gum), karaya gum (karaya gum), tragacanth gums (tragacanth gum), Gatti gum (ghatt i gum), guar gums (guar gum), there may be mentioned locust bean gum (locust bean gum) and four days Solarium seed gum (psyl l ium seed gum), etc., and specific examples of the trehalose-based thickener in the saelreul is a hydroxypropylmethylcellulose selreul OSU , carboxymethyl selreul as agarose, methyl selreul as agarose, hydroxymethyl selreul as agarose, hydroxy as hydroxyethyl saelreul agarose, hydroxypropyl saelreul as agarose, hydroxyethyl methyl selreul as agarose, hydroxy methyl propyl saelreul agarose, hydroxy hydroxyethyl may be mentioned agarose such as hydroxypropyl selreul OSU OSU as in, ethyl hydroxyethyl selreul and methylhydroxy ethoxypropyl selreul. On the other hand, specific examples of the hydroxy-containing polymers and the like can be mentioned polyethylene glycol and polyvinyl alcohol.

On the other hand, in order to perform the surface cross-linking, the surface cross-linking solution as the base resin the insert article banung common summing method, a method for spraying a surface cross-linking solution in the base resin, continuous surface with the base resin in the mixer crosslinking driven by there is a method to sum the liquid continuously supplied to shake or the like can be used.

In addition, the surface cross-linking is from 100 to 250 ° may be formed continuously to the drying and grinding step is conducted after a relatively high temperature may take place at a temperature of C. At this time. The surface cross-linking reaction may proceed for 1 to 120 minutes, or 1 to 100 minutes, or 10 to 60 minutes. That is, the cross-linking reaction can be carried out under the conditions of the aforementioned surface in order to prevent the surface cross-linking is induced while the banung mins when excess banung polymer particles damage the physical properties is reduced.

【Effects of the Invention】

As described above, the. Super-absorbent resin according to the present invention, is to develop the excellent absorption performance is preferably used in the sanitary material such as diapers can be exhibited an excellent performance.

- specific information for carrying out the invention;

Below, it is presented to a preferred embodiment for better understanding of the present invention. However, the practice of the following examples are not intended to limit the invention to these may make to illustrate the present invention.

Example

(Step 1)

Common in the combined solution the IRGACURE 819 initiator, 9 g (80 ppmw relative to the monomer composition) and a polyethylene glycol dilution to 5% acrylic acid diacrylate (PEGDA, Mw = 400) 40 g was diluted with 0.5% to acrylic acid (A solution) was prepared; In addition, the dilution to 5% acrylic acid allyl methacrylate (al lyl methacrylate) 2. 1 g to prepare a common combined solution (B solution).

25 ° of 2L capacity wrapped around the jacket is a pre-cooling heat medium C to the glass half cycle unggi, it was fed 490 g of acrylic acid and the A solution and the B solution. Then, the glass in the half unggi, 24% sodium hydroxide solution 850 g (C solution) was slowly added dropwise to heunhap. Junghwayeol by the temperature of the mixture from about

72 ° after confirming that rise to over C, I waited for the heunhap nyaenggak solution. This neutralization of the acrylic acid in the resultant solution heunhap degree was about 70 mol%. A surface active agent, to thereby prepare a sodium dodecyl sulfate silsul (sodium dodecylsul fate) solution (Dl solution) diluted in water to 5 g of 2%. In addition, prepare a sodium persulfate solution (solution E) 30 g was diluted with a sodium bicarbonate diluted to 4% in water (sodium bi carbonate) solution (D-2 solution) and 20 g, 4% in water. Then, the temperature of the solution heunhap about 45 ° when in nyaenggak C, was injected into the heunhap heunhap solution previously prepared D-1, D-2 and E in solution.

(Step 2)

Then, the light irradiation apparatus is mounted on the top and inside is 8 ( the tray of Vat form provided in a square polymerization reactor preheated to rc (tray, width 15 cm X 15 cm), was poured heunhap solution prepared in Step 1 then, it was irradiated with light in the heunhap solution. was confirmed that the gel from light irradiation point from the surface in about 20 seconds formed, it was confirmed that this takes place at the same time as the foam polymerization banung after about 30 seconds from light irradiation point, followed by , was further cut into a size of 3 cm X 3 cm in progress the polymerization banung for 2 min, taken out of the polymerized sheet in. then, the above cut through a meat chopper using the (meat chopper) and chops step (chopping) sheet was prepared as powder (crump). the average particle size of the produced powder (crump) is 1.5隱.

(Step 3)

Then it was possible in the air flow adjusted to the upper and lower oven dried to a powder (crump) prepared in Step 2. The water content of the dried powder is less than or equal to about 2%, 180 ° to flow the hot air (hot air) of C upward from the bottom for 15 minutes, to flow downwardly in the back above for 15 minutes, the powder (crump) to uniformly dry. The dried powder is ground in grinder, and then classified to obtain a base resin of 150 to 850 in size. This beam SAT of the prepared base resin was 35.4 g / g. The SAT correction was determined according to the following experimental examples.

(Step 4)

Thereafter, a 100 g base resin prepared as described in Step 3, and water 4 g, ethylene carbonate, 1 g, Aerosil 200 (l Aerosi 200, Evonik, Inc.) plus 0. 1 g of common plus cross-linking agent solution and then shake, 190 ° in C for 30 minutes and the surface cross-linking banung. And, crushing the resulting product and sieve (sieve) using a particle size of 150 to 850 in the surface cross-linking and to obtain a water-absorbent resin. Obtained and by adding Aerosil 200 0.1 g water-absorbent resin in a dry process to prepare a water-absorbent resin were combined in a dry state and common.

Example 2

(Step 1)

B solution using 1.3 g (allyl methacrylate (al lyl methacrylate) 1 g of common 2. The combined solution was diluted to 5% acrylic acid), and, D-2 solution (sodium bicarbonate diluted to 4% in water ( sodium bi carbonate) solution) heunhap solution was prepared in the same procedures as in step 1 of example 1 except for using 30 g.

(Step 2)

Then, the light irradiation apparatus is mounted on the top and inside the 80 ° tray of Vat form installed in a square polymerization preheated to C group in (tray, width 15 cm X 15 cm), was poured into a mixed solution prepared in the above step 1 . It was then irradiated with light in the heunhap solution. It was confirmed that the light irradiated from the time a gel formed from the surface in about 20 seconds, it was confirmed that at the same time and the foaming polymerization banung occurs from light irradiation point, after about 30 seconds. It was then cut into a size of 3 cm X 3 cm proceeding further polymerization banung for 2 minutes, and taken out of the polymerized sheet. Geurago was prepared in the cut sheets through a meat chopper using the (meat chopper) and chops step (chopping) to the powder (crump). The average particle size of the produced powder (crump) was 1.7 mm.

(Step 3)

Then it was possible in the air flow adjusted to the upper and lower oven dried to a powder (crump) prepared in Step 2. The water content of the dried powder is less than or equal to about 2%, 180 ° to flow the hot air (hot air) of C upward from the bottom for 15 minutes, to flow downwardly in the back above for 15 minutes, the powder (crump) to uniformly dry. The dried powder is ground in grinder, and then classified to 150 to 850 m to obtain a base resin of the size. This beam SAT of the prepared base resin was 36.1 g / g. The SAT correction was determined according to the following experimental examples.

(Step 4)

Then, a base resin 100 g prepared as described in Step 3, and water 4 g, ethylene carbonate, 1 g, propylene carbonate, 1 g, Aerosil 200 (Aerosil 200, Evonik Co.) 0.1 g a common combined cross-linking agent solution and the common sum of the following, 190 ° at C for 30 minutes and the surface cross-linking banung. And, crushing the resulting product and sieve (sieve) using a particle size of 150 to 850 in the surface cross-linking and to obtain a water-absorbent resin. In addition to the water-absorbent resin obtained and a powder of alumina (Alul30, Evonik Co.) 0.1 g was produced as a dry water-absorbent resin were combined in a dry state and common.

Example 3

(Step 1)

D-1 solution was prepared and is, heunhap solution in the same manner as in Step 1 of Example 1 above but using (sodium dodecyl silsul sulfate (sodium dodecyl sulfate) solution was diluted with water to 2%) 10 g.

(Step 2)

Then, the light irradiation apparatus is mounted on the top and inside the 80 ° tray of Vat form installed in a square polymerization preheated to C group in (tray, width 15 cm X 15 cm), was poured heunhap solution prepared in Step 1 . It was then irradiated with light in the heunhap solution. It was confirmed that the light irradiated from the time a gel formed from the surface in about 20 seconds, it was confirmed that at the same time and the foaming polymerization banung occurs from light irradiation point, after about 30 seconds. It was then cut into a size of 3 cm X 3 cm proceeding further polymerization banung for 2 minutes, and taken out of the polymerized sheet. And, to prepare the cut sheets through a meat chopper using the (meat chopper) and chops step (chopping) to the powder (crump). The average particle size of the produced powder (crump) is 1.2 mm.

(Step 3)

Then it was possible in the air flow adjusted to the upper and lower oven dried to a powder (crump) prepared in Step 2. The water content of the dried powder is less than or equal to about 2%, to flow upward from below the hot air (hot ai r) of 18CTC for 15 minutes, to flow downwardly in the back above for 15 minutes, even the powder (crump) it was dried. The dried powder is ground in grinder, and then classified to 150 to 850 urn to obtain a base resin of the size. This beam SAT of the prepared base resin was 34.2 g / g. The SAT correction was determined according to the following experimental examples.

(Step 4)

Thereafter, a 100 g base resin prepared as described in Step 3, and water 4 g, ethylene carbonate, 1 g, alumina powder (Alul30, Evonik Corporation) 0. 1 g of common plus cross-linking agent solution and the combined common and then, 190 ° at C 30 minutes was a surface cross-linking reaction. And, crushing the resulting product and sieve (sieve) using a particle size of 150 to 850 in the surface cross-linking and to obtain a water-absorbent resin. In addition to the water-absorbent resin obtained and a powder of alumina (Alul30, Evonik Corporation) 0. 1 g in a dry process to prepare a water-absorbent resin were combined in a dry state and common.

Comparative Example 1

Common in the combined solution the IRGACU E 819 initiator, 9 g of polyethylene glycol diacrylate dilution of 5% to (80 ppmw relative to the monomer composition) and acrylic acid (PEGDA, Mw = 400) 19 g was diluted with 0.5% to acrylic acid (A solution ) was prepared. In addition, ethylene oxide is a solution (B solution) 13 diluting the trimethylolpropane triacrylate (TMPTA-ethoxylated, TMP (E0) 9TA, M- 3190 Miwon Specialty Chemicals Co.) comprising 9 mol% to 5% acrylic acid g was prepared.

25 ° of 2L capacity wrapped around the jacket is a pre-cooling heat medium C to the glass half cycle unggi, it was fed 470 g of acrylic acid and the A solution and the B solution. Then, the glass in the half unggi, 24% sodium hydroxide solution 850 g (C solution) was slowly added dropwise to heunhap. Common in the temperature of about 72 hapaek by junghwayeol ° Check to rise to over C, waited for heunhap solution is cooled. Thus resulting in a degree of neutralization solution heunhap Oh rilsan was about 70 mol ¾>. The sodium persulfate solution was diluted to 4% in water (E solution) was prepared in 30 g. Then, the temperature of the solution heunhap about 45 ° when in nyaenggak C, was heunhap injecting a previously prepared solution E to the solution heunhap.

Then, the polymerization step and the chopper (chopping) was carried out in the same manner as in Example 1. The average particle size of the produced powder (crump) was 3.4 匪. Then, the drying and milling process was performed in the same manner as in Example 1. This beam SAT of the prepared base resin was 36.4 g / g. The beam SAT was measured according yesse following experiments. Next, the exemplary embodiment by the same method and then surface cross-linking treatment as in Example 1 to thereby give a superabsorbent resin.

Comparative Example 2

The acrylic acid (diluted with λ 5% IRGACURE 819 initiator, 11 g (a polyethylene glycol diacrylate diluted with a 5% to 80 ppmw) and acrylic acid with respect to the monomer composition (PEGDA, Mw = 400) 36 g of common combined solution (A solution) was prepared.

25 ° in advance of being wrapped around with a heat medium circulating jacket nyaenggak 2L capacity glass half unggi to C, 480 g of acrylic acid was injected with the A solution. Then, the glass in the half unggi, 24% sodium hydroxide solution 850 g (C solution) was slowly added dropwise to heunhap. After the temperature of the common hapaek by junghwayeol confirming that rises to at least about T2X, waited for heunhap solution is cooled. This neutralization of the acrylic acid in the resultant solution heunhap degree was about 70 mol%. The sodium persulfate solution was diluted to 4% in water (E solution) was prepared in 30 g. Then, the temperature of the solution heunhap about 45 ° when in nyaenggak C, was heunhap injecting a previously prepared solution E to the solution heunhap.

Then, the polymerization step and the chopper (chopping) was carried out in the same manner as in Example 1. The average particle size of the produced powder (crump) was 3.8 隱. Then, the drying and milling process was performed in the same manner as in Example 1. This beam SAT of the prepared base resin was 39.7 g / g. The SAT correction was determined according to the following experimental examples. Next, the exemplary embodiment by the same method and then surface cross-linking treatment as in Example 1 to thereby give a superabsorbent resin.

Comparative Example 3

Common in the combined solution the IRGACURE 819 initiator, 11 g of polyethylene glycol diacrylate (PEGDA, Mw = 400) 42 g was diluted to 5% (80 ppmw relative to the monomer composition) and acrylic acid diluted to 0.5% to acrylic acid (A solution) It was prepared.

25 ° in advance of being wrapped around with a heat medium circulating jacket nyaenggak 2L capacity glass half unggi to C, 470 g of acrylic acid was injected with the A solution. Then, the glass in the half unggi, 24% sodium hydroxide solution 850 g (C solution) was slowly added dropwise to heunhap. The common temperature hapaek junghwayeol by about 72 ° after confirming that rise to over C, waited for the heunhap nyaenggak solution. This neutralization of the acrylic acid in the resultant solution heunhap degree was about 70 mol%. A surfactant, a sugar ester of acrylic acid as a dilution in 1% (Sugar ester; S- 1670) to prepare a solution (D-3 solution) 1.8 g. In addition, prepare a sodium persulfate solution (solution E) 30 g was diluted with a sodium bicarbonate diluted to 4% in water (sodium bi carbonate) solution (D-4 solution) and 15 g, 4% in water. Then, the temperature of the solution heunhap about 45 ° when in nyaenggak C, prepared in the mummy heunhap solution D-3, was injected into the heunhap D- and E 4 solution.

Then, the polymerization step and the chopper (chopping) was carried out in the same manner as in Example 1. The average particle size of the produced powder (crump) was 2.8 瞧. Then, the drying and milling process was performed in the same manner as in Example 1. This beam SAT of the prepared base resin is 38.4. g / g, respectively. The SAT correction was determined according to the following experimental examples. Next, the exemplary embodiment by the same method and then surface cross-linking treatment as in Example 1 to thereby give a superabsorbent resin.

Comparative Example 4

Common in the combined solution the polyethylene glycol diacrylate (PEGDA, Mw = 400) 32 g was diluted to 5% (80 ppmw relative to the monomer composition) and acrylic acid with IRGACU E 819 initiator 11 g dilution with 0.5% to acrylic acid (A solution ) was prepared.

25 ° in advance of being wrapped around with a heat medium circulating jacket nyaenggak 2L capacity glass half unggi to C, 470 g of acrylic acid was injected with the A solution. Then, the glass in the half unggi, 24% sodium hydroxide solution 850 g (C solution) was slowly added dropwise to heunhap. The common temperature hapaek junghwayeol by about 72 ° after confirming that rise to over C, waited for the heunhap nyaenggak solution. This neutralization of the acrylic acid in the resultant solution heunhap degree was about 70 mol%. A surfactant, a sugar ester of acrylic acid is diluted to a 1% (Sugar ester; S- 1670) to prepare a solution (D-5 solution) 2. 1 g. In addition, prepare a sodium persulfate solution (solution E) 30 g was diluted with 4% in water. Then, the temperature of the solution heunhap about 45 ° when in nyaenggak C, was heunhap injecting a previously prepared solution of D-5 and E in the heunhap solution.

Then, the polymerization step and the chopper (chopping) was carried out in the same manner as in Example 1. The average particle size of the produced powder (crump) was 4.4 隱. Then, in Example 1, the drying and grinding step in the same manner

It was performed. This beam SAT of the prepared base resin was 44.5 g / g. The SAT correction was determined according to the following experimental examples. Next, the exemplary embodiment by the same method and then surface cross-linking treatment as in Example 1 to thereby give a superabsorbent resin.

Comparative Example 5

For comparison, four commercially Sandi a production and sale products (product name: IM-930) were from the in Comparative Example 5.

Experimental Example: Evaluation of physical properties of the superabsorbent resin

Evaluated the physical properties of a super-absorbent resin prepared in Examples and Comparative Examples by the method, the results are shown in Table 2.

(1) absorption capacity under pressure (AUL, Absorbing under Load)

The above Examples and Comparative Examples and the pressure absorption capacity (AUL) of 0.9 psi for a physiological saline solution of the water-absorbent resin were measured according to the method of the method EDANA WSP 242.2. And by of the water absorbent resin passing through the US standard 30 mesh screen, and the screened superabsorbent polymer is maintained above the US standard 50 mesh screen, particle size of 300 iM to 600 / in and with respect to the water absorbent resin to be measured, to measure the AUL .

Specifically, the stainless steel cylinder having an inner diameter of the bottom of a plastic 25 睡

It was fitted with a 400 mesh screen. Then, the absorbent and to measure the absorption capacity under pressure to the screen under the normal temperature and humidity of 50% resin W 0 (g, from about 0. 16 g) was uniformly sprayed. Then, the high was added to a piston (piston) that can be more uniformly impart a load of 6.3 kPa (0.9 psi) over the water-absorbent resin. At this time, the piston has no inner walls and openings of the outer cylinder is slightly smaller than 25 mm, was used as a designed to be moved up and down topge freedom. And to measure the weight Kg) of thus prepared device.

Then, the diameter 90 on the inside of the dish with a diameter of 150 Petro 匪 隱, laying a glass filter having a thickness of 5 隱, was poured into the physiological saline solution of 0.9% by weight in the petro plate. In this case, the poured physiological saline until the physiological saline surface is the top side and the level of the glass filter. Then, the filter paper placed one having a diameter of 90 mm on the glass filter.

Then, the super-absorbent resin in the topped with a device prepared on the filter paper device was allowed to swell with physiological saline under a load. After 1 hour, the weight W of containing the swollen superabsorbent polymer device 2 was measured (g).

To use the thus-measured weight it was calculated according to equation 1 the pressure absorption capacity.

Equation 1

AUP(g/g) = [ff2(g) - Wi(g)]/ W0(g)

In the equation (1),

W 0 ( g a) is the initial weight (g) of the superabsorbent polymer, Kg) is the sum of the unit weight which can impart a load to the weight and the high water-absorbent resin having a high water-absorbent resin, W 2 (g) is a load and wherein for one hour under (0.9 psi) it is the total weight of the device that can after absorption of physiological saline, to give the load weight, and the super-absorbent resin having a high water-absorbent resin to the water-absorbent resin.

(2) Gel-AUL

Using the same equipment used in the above (1) absorption capacity under pressure, to measure the AUL of a Gel-0.3 psi. Of the super-absorbent resin to be measured, the United States passes through a standard 30 mesh screen, US Standard 50 by mesh screening the superabsorbent polymer is maintained above the screen, the particle size is about the 300 to 600 superabsorbent polymer, was measured for Gel-AUL .

Specifically, the examples and the comparative resin W obtained in Example 0, and then into the (g, 0.16 g), the AUL ki t used in the above "(1) a pressure absorption capacity, addition of a piston capable of imparting a 0.3 psi load, to do this was measured for weight (g) of the finished device. Then remove the piston and immersed the superabsorbent resin in samurai reduction in saline solution of 1.5 g was swollen primary. Then 0.3 ps i pressurized under 15 minutes 30 seconds under a 5 psi in vacuo after absorption of physiological saline by vacuum desorption to remove the saline solution present between the gel and the gel and, AUL ki t laden is completely gel, including saline for the weight (g) was measured.

To do this, using the each obtained mass was determined 15 minutes gel-AUL (g / g) of 0.3 psi according to the following expression (2).

Equation (2)

15 of 0.3 psi AUL-minute gel (g / g) = [W 4 (g) - W 3 (g)] / W 0 (g)

In Equation 2,

W 0 (g) is the initial weight (0. 16 g) of the superabsorbent resin,

W 3 , and (g) is a super-absorbent resin The initial weight and the sum of i and 0.3 ps unit weight that can impart a load (g) of the water-absorbent resin,

W 4 (g) is that the in samurai reduction to absorb physiological saline 1.5 g in the water-absorbent resin primary swelling and, 0.3 psi 15 minutes under pressure absorbs the saline solution and for, under 5 psi was for 30 seconds, the vacuum desorption in vacuo is then super-absorbent resin and the high total weight (g) Weight of the device capable of providing a 0.3 psi load of the water-absorbent resin.

Further, but as defined above, by changing the load of 0.3 psi to 0.6 psi was measured for Gel-AUL of 0.6 psi.

(3) centrifuging beam SAT (Centrifuge Retention Capacity, CRC) European Nonwoven Industry Association (European Di sposables and Nonwovens Associ at ion, EDANA) standard EDANA Examples and Comparative Examples and with respect to the water absorbent resin, Mucha Heavy absorption according to WSP 241.3 a centrifuge beam SAT (CRC) according to the scale was measured. Of the super-absorbent resin to be measured, the US standard 30 through the mesh screen, and the screened superabsorbent polymer is maintained above the US standard 50 mesh screen, particle size of 300 / zm to 600 at a high relative to the water-absorbent resin were measured CRC .

Specifically, Examples and Comparative Examples Resin W 0 (g, about 0.2 g) After put uniformly on the envelope of the nonwoven fabric is sealed (seal), was submerged in the saline solution is a sodium chloride solution of 0.9 weight% at room temperature . After 30 minutes using a centrifuge after the envelope, leave for 3 minutes to dry the mass of the bag 250G W 6 was measured (g). Also at that time and a weight w after the same manner without using the water-absorbent resin 5 it was measured (g). Eu

To do this, using the each obtained mass was calculated CRC (g / g) according to the equation (3).

[Equation 3]

CRC(g/g) = { [W6(g) - W5(g) - W0(g) ] /Wo(g) }

In Equation (3),

W 0 (g) is the initial weight (g) of the superabsorbent resin,

W 5 (g) without the use of superabsorbent polymer, and in which absorption by immersion for 30 minutes in physiological saline solution and the weight measuring device after using the centrifuge dehydrated 3 minutes at 250G,

W 6 (g) is then, using the following, the centrifuge was absorbed at room temperature, and submerged in saline solution to the absorbent resin for 30 minutes, dehydrated 3 minutes at 250G, and a measuring device, including the water-absorbent resin weight.

(4) the gel bed permeability (GBP, Gel Bed Permeabi l ity)

Examples and Comparative Examples and a free swell gel bed permeability (GBP) of the physiological saline solution of the water-absorbent resin were measured according to the following method described in Korea Patent Application No. 10-2014-7018005 call.

Specifically, measuring the Free Swell GBP Korea was used as the apparatus shown in Patent Application Serial No. 10-2014-7018005. 1 to Fig. 3 of Fig order. First, the weight 548 is to position the plunger device 536 is in an empty sample container 530, of using a suitable gauge accurate to 0.01mm, to the bottom of the sample container 530 from the top of the weight 548 It was measured height. During measurement, force applied to the thickness gauge was adjusted to less than about 0.74N.

On the other hand, the US standard 30 mesh screen of the super-absorbent resin to be measured is passed, and the GBP, US standard 50 mesh screened superabsorbent polymer is maintained above the screen to obtain a particle size of superabsorbent polymer 300 to 600 // m.

Thus, insert the super-absorbent resin of the classified about 2.0g in the sample container 530, spread evenly over the bottom of the sample vessel. Then, the high-soaked for about 60 minutes under no pressure in the container does not include a plunger 536 and weight 548 in the condition of 0.9% saline solution was swell the water-absorbent resin. At this time, the sample vessel 530, the effect on the movement of the physiological saline to was placed so that a bit up than the bottom of the liquid storage eulryeo the sample containers 530 on a mesh located in the liquid reservoir, roneun the mesh sample containers 530 that we do not use. The surface in the sample vessel while the height of the saline solution is saturated was adjusted to defined by the superabsorbent polymer swelling rather than saline.

At the end of this period, the plunger 536, and then the sample container 530, plunger 536 is placed eulryeo over the swollen superabsorbent polymer 568 in the assembly of the weight 548, the sample vessel 530, the weight ( 548) and the swollen and pulled out the water-absorbent resin (568) from the solution. Since, GBP Before measurement, the sample container 530, plunger 536, weight 548, and swelling the highly uniform thickness ratio of the flat, large grid for a water-absorbent resin (568) for about 30 seconds on the deformable plate while kept intact. Then, by using the same thickness gauge that was used previously to measure the height of the bottom of the sample container 530 from the top of the weight 548 again. Then, the above estimation 548, a swelling of the device, the plunger (536) swelling the height measured values ​​of that device located in the empty sample container 530 and the second on the height measurement of the unit containing the water-absorbent resin (568) the high thickness of the black water-absorbent resin was determined the height "H".

For GBP measurements, the swelling superabsorbent resin 568, the plunger 536 and weight 548 were flowing through the lead 9 weight% physiological saline solution in the sample vessel 530 containing the control. Saline were to consistent head pressure equal to the height of the overflow so that the sample container 530, the flow rate of the saline solution in the (f low rate) adjusted to a sample container 530 is shown in the upper portion of the cylinder 534. Then, by using the scale 602 and a beaker 603, the amount of time for the solution to pass through the swollen high-absorbent resin 568 it was measured by a weight measuring method. Once the overflow begins, and collecting data points from the scale 602 per second for at least 60 seconds. To a swelling and through the water-absorbent resin (568) flow rate (Q) is a linear least squares fit of the fluid (g) vs. time (sec) of the swollen and pass through the water-absorbent resin 568 (l inear least-square fit) by decided g / sec unit.

To do this using the obtained data value, the GBP (cm according to the following equation (4) of the two yielded a).

[Equation 4]

= [QXHX m] / [A X P px]

In Equation (4),

Κ the gel bed permeability (cm 2 a),

Q is the flow rate (g / sec),

H is the height (cm) of the swollen superabsorbent polymer,

μ is the liquid viscosity (Ρ) and (viscosity of physiological saline used in this test is about 1 cP),

A is (28.27 ciif for the sample containers used for this test), the cross-sectional area for liquid flow,

p is the liquid density (g / cm 3 ) (about 1 g / cm for a physiological saline solution used in this Test 3 , and),

P is the hydrostatic pressure (dyne / cm 2 ) (normally approximately 7, 797 dyne / cm 2 a).

Hydrostatic pressure is calculated from the equation P = X pg h, where p is the liquid density (g / cm 3 a), g is the acceleration of gravity (cm nominally in the 981 / sec 2 a), h is

A filling height (e.g., 7.95 cm for the GBP test described herein).

Testing the at least two samples, and as a result, and that by the average determining the Free Swell GBP of the water-absorbent resin, a conversion unit (Idarcy = 0.98692 x 10 darcy as "8 cm 2 are shown in Table 1).

5, the absorption rate (Vortex time)

Examples and Comparative Examples and the absorption rate of the absorbent resin was measured in seconds according to the method described in International Patent Publication No. 1987-003208 to call.

Specifically, the rate of absorption (or vortex t ime) is 23 ° C to 24 ° stirring saline 50 mL of C into the super-absorbent resin of 2g, magnetic bars (diameter: 8 mm, length 31.8隱) at 600 rpm and it was calculated by measuring the time until the vortex (vortex) disappear in seconds.

The results measured as described above in Table 1 below.

[Table 11

[Claims]
[Claim 1]
Water-soluble ethylenic base resin including a first cross-linked polymer of an unsaturated monomer having a powder at least partially neutralizing the acid; And

A superabsorbent polymer comprising a surface cross-linked layer is formed on the base of the resin powder, the crosslinked polymer to 1, and includes a more cross-linked second cross-linked polymer to the surface cross-linking agent as a medium,

And a 0.3 psi AUL-gel 15 bun at least 13 g / g,

AUL is at least 18 g / g,

And a gel bed permeability (GBP) of 30 Darcy (darcy) above,

The absorption rate is not more than 45 seconds, the superabsorbent polymer measured according to the measurement method Vortex.

[Claim 2]

I in the U, wherein

15 minutes of gel-AUL 0.6 psi is 12 g / g or more,

Superabsorbent polymer.

[Claim 3]

' According to claim 1,

Centrifugation beam SAT (CRC) is 29 g / g or more,

Superabsorbent polymer.

[Claim 4]

According to claim 1,

And the average particle diameter of the water-absorbent resin is 300 to 600 of, the superabsorbent resin.

[5.]

Crab according to claim 1, wherein

The high-containing water-absorbent resin particle diameter of 300 to 600 of super-absorbent resin of a 45 to 85 wt ¾>,

Superabsorbent polymer.

[6.]

Further comprising: in the presence of an internal cross-linking agent, a blowing agent and a surfactant, by cross-linking polymerization of the water-soluble ethylenically unsaturated monomer having at least some of the neutralizing acid to form a hydrogel polymer comprising a first cross-linked polymer;

The method comprising the average particle diameter to tighten the hydrogel polymer pulverized to prepare a hydrogel polymer 1.0 mm to 2.0 隱;

The method comprising the hydrogel polymer was dried and pulverized to prepare a base resin powder; And

In the presence of a surface crosslinking agent, by heat-treating the surface cross-linking the base resin powder and a step of producing a water-absorbent resin particles,

The method of superabsorbent polymer.

[7.]

7. The method of claim 6,

The foaming agent is sodium bicarbonate (sodium bi carbonate), sodium carbonate (sodium carbonate), potassium bicarbonate (potassium bi carbonate), potassium carbonyl you 1 byte (potassium carbonate), calcium bicarbonate (calcium bicarbonate), calcium carbonate (calcium a bicarbonate), magnesium non-7-carbonate (magnesiumbi carbonate) or 1 "magnesium ^!" carbonate (magnesium carbonate),

The method of superabsorbent polymer.

[8.]

In going to 17,

The foaming agent is used more than 1500 ppmw contrast weight of the water-soluble ethylenically unsaturated monomer,

Method for producing a superabsorbent resin

[9.]

In to 6,

The surfactant to method for producing a high water-absorbent resin compound represented by the formula (2):

[Formula 2]

R-S03Na

In Formula 2,

R is alkyl having 8 to 16.

[10.]

10. The method of claim 9,

The surfactant used in less than the weight of the water-soluble ethylenically unsaturated monomer 300 ppmw,

The method of superabsorbent polymer.

[Claim 11]

Water-soluble ethylenic base resin including a first cross-linked polymer of an unsaturated monomer having a powder at least partially neutralizing the acid; And

A super-absorbent resin to the first cross-linked polymer is formed on the base resin powder, a cross-linked layer includes a surface including a second cross-linked polymer cross-linking a surface cross-linking agent is added to the medium,

And 15 minutes of 0.3 psi AUL-gel at least 13 gig,

And a gel bed permeability (GBP) of 30 Darcy (darcy) above,

The absorption rate is not more than 45 seconds, the superabsorbent polymer measured according to the measurement method Vortex.