JP2947637B2 - Bis (N-vinylcarboxylic acid amide) compound, crosslinked polymer using the same, process for producing the same, and liquid absorbent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel bis (N-vinylcarboxylic acid amide) compound which is useful, for example, as a crosslinking agent for producing a crosslinked polymer. The present invention is also produced using the novel compound, excellent in gel strength and chemical stability, its properties are less affected by the electrolyte solution, water, alcohol and other organic solvents The present invention relates to a novel crosslinked polymer having affinity and a method for producing the same.

[0002] The present invention further relates to a water or organic solvent mainly containing a crosslinked N-vinylcarboxylic acid amide resin obtained by crosslinking the main chain of a homo- or copolymer containing an N-vinylcarboxylic acid amide component with a crosslinking agent. Related to liquid absorbent.
More specifically, the present invention is chemically stable, has excellent absorption capacity for organic solvents such as water and alcohols,
It has a good absorption rate for liquids in which metal ions and organic ions coexist in the system, and is less affected by coexisting ions. In addition, as a result of absorbing liquid, the liquid itself swells and gels, making the coexisting liquid system non-fluid and solidifying,
The present invention relates to a liquid absorbent having a wide range of applications in various fields, utilizing the excellent features and functions of an iso-crosslinked N-vinylcarboxylic acid amide resin exhibiting sustained release and adhesion.

[0003]

2. Description of the Related Art Crosslinked polymers are known for their solvent insolubility,
Since it often has special properties different from non-crosslinked polymers in terms of strength as a material and other points, it is industrially used for various purposes such as photosensitive resins and reinforcing materials. In particular, in recent years, a water-swellable polymer (hydrogel) having a crosslinked structure of a water-soluble polymer has been attracting attention in various industrial fields utilizing its water absorption and water retention. For example, applications and research in hygiene materials such as disposable diapers, sanitary products, contact lenses, cosmetics, paints, adhesives, water blocking agents, soil modifiers, and other medical fields such as controlled drug release are active. . Research and development are also being conducted on application fields that utilize the stimulus responsiveness of hydrogels to pH, heat, light, solvents, and the like.

[0004] These crosslinked polymers are produced by various methods, but as a method often used industrially, one or more kinds of vinyl compounds are added as a monomer by a method such as radical polymerization. A compound having a plurality of functional groups such as a vinyl group copolymerizable with the vinyl compound when a polymer is obtained by polymerization (ie, a crosslinking agent)
Is typically introduced by introducing a crosslinking point into the polymer chain by copolymerizing

As a cross-linking agent used for producing a hydrogel or other cross-linked polymer by the above-mentioned method, a compound having a plurality of vinyl groups copolymerizable with the monomer is generally used. Examples of such crosslinking agents currently known include a plurality of acrylic groups such as N, N'-methylenebisacrylamide, ethylene glycol di (meth) acrylate, and trimethylolpropane tri (meth) acrylate. And / or compounds having two or more unsaturated groups in one molecule, such as compounds having a methacryl group, triallyl isocyanurate, and divinylbenzene.

[0006] However, as described above, compounds capable of functioning as a cross-linking agent are known to have various structures, but depending on the use of the cross-linked polymer and the type of the monomer, the performance, structure and the like are not necessarily required. In many cases, there were no cross-linking agents that met all the requirements. For example, copolymerizability of a vinyl compound as a monomer and a crosslinking agent,
This is the case where a cross-linking agent having a performance that sufficiently satisfies conditions such as solubility of the cross-linking agent in a solvent and stability upon denaturation after cross-linking is not known. When an attempt is made to synthesize a cross-linked polymer using a cross-linking agent that does not sufficiently meet the intended requirements, the cross-linking reaction does not proceed uniformly, so that the cross-linking agent is not effectively used and thus obtained. Insufficient strength of the crosslinked polymer, a large amount of polymer soluble in the solvent due to insufficient crosslinkage, or an extremely large amount of crosslinking agent necessary to obtain a satisfactory crosslinked polymer Problems occur. In particular, the copolymerizability of the vinyl group and the monomer in the cross-linking agent is an important factor. No coalescence is obtained. In the present specification, the expression `` the copolymerizability of the monomer and the crosslinking agent is good '' is the reactivity of the vinyl group of the crosslinking agent and the vinyl group of the monomer, as defined in the Mayo-Lewis formula. Ratio r ₁ , r ₂
Is a close value and means a system in which the cross-linking point is relatively uniformly introduced into the polymer molecular chain from the beginning to the end of the polymerization reaction.

For example, N-vinylpyrrolidone is often used as a monomer to give a hydrophilic polymer by polymerization, and its crosslinked polymer is suitable as a hydrogel for applications such as contact lenses. Almost no crosslinking agent having a vinyl group and a vinyl group having good copolymerizability has been known.

Further, the present inventors have previously described the following formula [6]:

[0009]

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(Wherein, R ¹ and R ⁵ each independently represent a hydrogen atom or a methyl group) by polymerizing a monomer containing N-vinylcarboxylic acid amide as a main component in the presence of a crosslinking agent. As a result, a water-swellable crosslinked polymer containing a repeating unit derived from the monomer of the formula [6] in a structural unit in an amount of 50 to 100 mol% (excluding a branched structure derived from a crosslinking agent) is obtained. When the performance of the coalesced resin as a water-absorbing resin was evaluated, it was found that the crosslinked polymer had a high absorptivity to the aqueous electrolyte solution and could be produced by an economical and simple production method. 1
A patent application was previously filed as -302409. That is, most of the conventional so-called water-absorbing polymers are based on polycarboxylic acids, and their water-absorbing ability largely depends on the electrolyte concentration solution in the aqueous solution. Furthermore, when polyvalent metal ions are present in the electrolyte, the swelling rate of the polymer cannot be prevented from being significantly reduced due to ionic crosslinking between molecular chains of the polymer. A water-swellable crosslinked polymer containing 50 to 100 mol% of a repeating unit derived from an N-vinylcarboxylic acid amide represented by the formula [6] (excluding a branched structure derived from a crosslinking agent) is prepared by a conventional crosslinking method. It is a novel crosslinked polymer with features not found in polymers. In other words, this crosslinked polymer is a hydrophilic and water-swellable gel, but also has an affinity for certain organic solvents such as alcohol, dimethylformamide, and dimethylsulfoxide, and absorbs these solvents. Can swell. It was also found that this crosslinked polymer was hardly affected by the electrolyte in the solution.
Therefore, when a water-absorbing resin was produced using a known cross-linking agent such as those mentioned above as a cross-linking agent, compared with the conventional water-absorbing resin, it was extremely excellent particularly in the absorption rate for an aqueous electrolyte solution and the like. One with performance was obtained. However, since the copolymerizability of the N-vinylcarboxylic acid amide and the crosslinking agent is not always good, the crosslinking is not sufficiently performed, and a polymer soluble in a solvent is generated or a crosslinked polymer having a sufficient crosslinking density is obtained. However, there is a problem that the amount of the cross-linking agent necessary for the above-mentioned process becomes very large. Therefore, in order to further improve the performance of this crosslinked polymer as a water-swellable gel, it has been desired to develop a crosslinker having good copolymerizability with N-vinylcarboxylic acid amide.

In order to further solve the above problems, the present inventors have studied the development of a novel crosslinking agent, and have found that N, N'-methylenebis (N-vinylcarboxylic acid having the structure of the following chemical formula [7] Amide) can be produced by a simple method and is particularly suitable as a crosslinking agent in the production of a crosslinked polymer containing an N-vinyl compound as a main component. Filed a patent application.

[0012]

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(In the formula, R ¹ represents a hydrogen atom or a methyl group.)

However, since the compound of the formula [7] has good polymerizability with an N-vinyl compound, the production of a crosslinked polymer mainly using a water-absorbing resin containing an N-vinyl compound as a main component is considered. As compared with the case of using an existing cross-linking agent, a polymer excellent in strength, water absorption and the like can be obtained, but two vinyl groups in the molecule of the formula [7] Because of the close proximity, self-cyclization reaction is likely to occur during the polymerization, so that it is not efficient to introduce a cross-linking point or that the nitrogen atom of the N-vinyl compound has 2 carbon atoms at the carbon atom of the methylene group.
Further improvements have been desired, such as not being always satisfactory in terms of chemical stability, for example, hydrolysis resistance, etc. due to the structure of individual bonding.

On the other hand, water-absorbing resins are widely used in the fields of medicine, sanitary, food industry, agriculture, civil engineering, etc. by utilizing their water absorption and water retention. In each case, a high swelling ratio and a high gel strength are required.
Examples of the conventionally known water-absorbing resin include, for example, a hydrolyzate of a starch-acrylonitrile graft copolymer, a neutralized product of a starch-acrylic acid graft copolymer, and vinyl acetate-
Examples include saponified acrylate copolymers, hydrolyzed acrylonitrile or acrylamide copolymer crosslinked products, and polyacrylate crosslinked products. However, these water-absorbing resins are all crosslinked with a polyelectrolyte, and therefore exhibit excellent swelling performance with respect to water containing no electrolyte. However, blood, urine, aqueous fertilizers, cement slurries, etc. It has a significantly lower swelling property for aqueous liquids containing high amounts of these electrolytes. It is considered that such a phenomenon appears as a result of a reduction in the spread of the chain because the dissociation of the polymer electrolyte which is the main chain of the crosslinked product is suppressed in the presence of ions. Furthermore, when polyvalent metal ions are present, ionic cross-linking occurs further via the main chain carboxylic acid, and a cross-linked polymer having an unnecessarily high cross-link density also contributes to a decrease in the swelling ratio.

In order to solve such a drawback, for example,
Japanese Patent Application Laid-Open No. 61-97312 discloses a method for producing a water-absorbent resin containing a carboxyl group in a chain structural unit by graft-polymerizing an acrylic acid compound or the like onto hydroxyethyl cellulose and then hydrolyzing it. This is a method of obtaining an ion-resistant water-absorbing resin by introducing a nonionic polymer into the polymer electrolyte main chain, but it is not always necessary in terms of the chemical stability of the main chain or the simplicity of the manufacturing method. This is not a satisfactory method. JP-A-60-55011 discloses that three kinds of compounds, a (meth) acrylamide-based compound, a (meth) acrylic-acid-based compound and a (meth) acryl-based compound having a sulfonic acid group at a terminal, are used as divinyl-based compounds. A method for producing a water-absorbent resin having improved ability to absorb an aqueous solution of an electrolyte such as a saline solution by polymerizing in the presence of the same is disclosed. Further, a water-swellable crosslinked polymer containing an N-vinyl compound is proposed in Japanese Patent Application Laid-Open No. 58-5305, but any of them introduces a relatively strong dissociation group having an ionic dissociation strength, so that it can be used in an electrolyte solution. In order to avoid the suppression of the spread of the main chain, a (meth) acrylamide or N-vinyl compound is not substantially a main component, and a water-absorbent resin having high ionic resistance is obtained. Has not been reached. Furthermore, as described above, since the main chain is a polyelectrolyte, the swollen gel necessarily contains a large amount of electrolyte, and therefore, the water retention gel is used as a water replenishing material for agricultural use or the like. However, it cannot be said that the material is sufficiently effective, and a material having a high function has been demanded in this field.
Similarly, these rehydration materials are required to have excellent light resistance due to their usage, but this point has not yet been sufficiently solved.

As the name implies, conventional water-absorbing resins form a gel by absorbing water, but these resins do not exhibit any swelling properties in organic solvents such as alcohols. Therefore, its use has been limited to purposes such as water absorption and water retention.

[0018]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve some problems, such as copolymerizability with a polymerizable monomer, of a conventional crosslinking agent for producing a crosslinked polymer, especially N-
In the production of a cross-linked polymer containing a vinyl carboxylic acid amide compound as one component, a cross-linking agent that has good copolymerizability with a monomer, has excellent chemical stability, and can provide a good cross-linked polymer. And a crosslinked polymer obtained therefrom.

The present invention also has the disadvantages of the conventionally known water-absorbing resins represented by crosslinked sodium polyacrylate,
In particular, the liquid (electrolyte solution) in which inorganic and organic ions such as metal salts, amines, and carboxylic acids coexist has a significant decrease in absorption capacity and is a disadvantage of natural polymer compounds or their chemically modified products. Improves the lack of stability, furthermore, it has an absorption capacity not only for aqueous systems but also for alcohols and other organic solvents, and the gel formed by absorption of the liquid has good adhesion and is absorbed. An object of the present invention is to develop a liquid absorbent having excellent performance in reusing water by plants and the like.

[0020]

According to the present invention, the formula [1]:

[0021]

Embedded image [Wherein, R ¹ represents a hydrogen atom or a methyl group, R ² represents an alkylene group having 3 to 10 carbon atoms; a group — (CH ₂ .CHR ³ .O) _n −
CH ₂ · CHR ^3- (wherein, R ³ represents a hydrogen atom or a methyl group, and n represents an integer of 1 to 4);

Embedded image (Where m represents 0 or 4)]
-Vinylcarboxylic acid amide) compounds are provided.

According to the present invention, the molar ratio of (i) the monomer repeating unit represented by the formula [2] or [3] to (ii) the crosslinking unit repeating unit represented by the formula [1 '] is also defined. [(I) / (ii)] provides a crosslinked polymer comprising 30/70 to 99.9999 / 0.0001 in a ratio.

[0023]

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[0024]

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[0025]

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[Wherein R ¹ , R ⁴ , R ⁵ and R ⁶ each independently represent hydrogen or a methyl group, and R ² has 3 to 3 carbon atoms.
10 alkylene groups; group-(CH ₂ · CHR ³ · O) _n -CH ₂ · CHR ³
-(Wherein, R ³ represents a hydrogen atom or a methyl group, and n is 1
Represents an integer of from 1 to 4);

[0027]

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(Wherein m represents 0 or 4), A represents 2-
Shows a ketopyrrolidinyl group. ]

According to the present invention, a monomer represented by the formula [2 '] or N-vinyl-2-pyrrolidone is further copolymerized with a bis (N-vinylcarboxylic acid amide) compound of the formula [1]. A method for producing the above crosslinked polymer is provided.

[0030]

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[0031]

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(Wherein R ¹ , R ² , R ³ and R ⁴ are as defined above)

According to the present invention, further, a monomer repeating unit represented by the formula (i) (a) (2) and a monomer (b) represented by the formula (4) and / or the formula (5) A monomer repeating unit containing a repeating unit in a molar ratio of ((a) / (b)) of 30/70 to 99/1; and (ii) a crosslinking agent repeating unit represented by the formula [1 ']. In a molar ratio [(i) / (ii)] of 30/70 to 99.
A crosslinked polymer comprising 9999 / 0.0001 is provided.

[0034]

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[0035]

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[0036]

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[0037]

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Wherein R ¹ , R ² , R ⁴ and R ⁵ are as defined above, R ⁷ is a hydrogen atom or a methyl group, A ′ is a group —COOX (where X is hydrogen An atom, an alkali metal, an alkyl group having 1 to 6 carbon atoms or a lower alkyl group substituted with a hydroxyl group, a dialkylamino group or a quaternary ammonium group; a group -CONHY (where Y is a hydrogen atom or a dialkylamino A lower alkyl group substituted with a quaternary ammonium group, a sulfonic acid or an alkali metal salt thereof); a cyano group; a 2-ketopyrrolidinyl group; a lower alkoxy group; a lower acyl group; a lower acyloxy group or a sulfonic acid or a sulfonic acid or the same. Represents a lower alkyl group substituted with an alkali metal salt, M represents a hydrogen atom, an ammonium group or an alkali metal, and p represents 0 or 1,
When R ⁷ is a methyl group, A ′ is not a cyano group, a 2-ketopyrrolidinyl group; a lower alkoxy group; a lower acyl group; a lower acyloxy group or a lower alkyl group substituted with sulfonic acid or a salt thereof. ]

According to the present invention, (i) (a) a monomer represented by the formula [2 '] and (b) a monomer represented by the formula [4'] and / or [5 '] CH ₂ = CR ⁷ A '[4'] MOOCCH = CH (CH ₂ ) _p COOM [5 '] (wherein R ⁷ , A', M and p are as defined above) (ii) There is provided a method for producing the above crosslinked copolymer, comprising copolymerizing a bis (N-vinylcarboxylic acid amide) compound of the formula [1].

[0040]

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[0041]

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(Wherein R ¹ , R ² , R ⁴ and R ⁵ are as defined above)

According to the present invention, there is further provided a liquid absorbent for water or an organic solvent containing at least one of the above-mentioned crosslinked polymers as a main component.

Hereinafter, the present invention will be described in more detail. The compound [1] of the present invention can be synthesized using various known organic synthesis reactions. For example, N-vinylcarboxylic acid amide is used as a starting material, and is reacted with a compound having two suitable leaving groups to replace a hydrogen atom bonded to a nitrogen atom of N-vinylcarboxylic acid amide with an alkyl group. -A route synthesized by an alkylation reaction is simple.

N-vinylcarboxylic acid amide is, for example, N- (α-alkoxyethyl) easily synthesized from acetaldehyde and carboxylic acid amide and alcohol, or by electrolysis of N-ethylcarboxylic acid amide in the presence of alcohol. It can be synthesized by thermally decomposing an acylamide (see JP-A-50-76015). Alternatively, it can be synthesized by thermal decomposition of ethylidene bisacetamide synthesized from acetaldehyde and acetamide (see The Journal of American Chemical Society, Vol. 98, p. 5996, 1976).

Compounds having two suitable leaving groups used for N-alkylation of N-vinylcarboxylic acid amide include, for example, alkyl halide, p-toluenesulfonic acid ester (tosylate), p-bromobenzene Leaving groups such as sulfonates (brosylate), p-nitrobenzenesulfonate (nosylate), methanesulfonate (mesylate), trifluoromethanesulfonate (triflate), nonafluorobutanesulfonate (nonaflate) and the like Compounds having two per molecule are suitable, preferably chlorides, bromides and tosyl esters, particularly preferably tosyl esters. Examples of such precursors of the compound of the present invention include 1,3-propane dichloride, 1,3-propane dibromide, 1,3-propanediol ditosylate, 1,4-butane dibromide,
1,4-butanediol ditosylate, 1,10-decanediol ditosylate, diethylene glycol dichloride, diethylene glycol ditosylate, triethylene glycol ditosylate, p-xylylene dichloride, 1,4-cyclohexanedimethanol ditosylate Rate and the like. Of these precursors, dihalides are relatively easily available in many cases, and tosyl esters are more easily available than polyhalide compounds, and diol compounds are tosylated by a known method using tosyl chloride or the like. Can be easily obtained.

Using these precursors (dihalide, ditosylate, etc.) and N-vinylcarboxylic acid amide,
There are several ways to carry out the alkylation reaction to obtain the desired compounds of the invention. For example, a method in which two raw materials are simultaneously present in a system in which an aqueous phase and an organic phase are in contact with each other, and are reacted using a phase transfer catalyst in the presence of a base catalyst such as sodium hydroxide, or a method such as dimethylformamide in advance. Using a base such as sodium hydride in an aprotic polar solvent to extract the hydrogen atom bonded to the nitrogen atom of the N-vinylcarboxylic acid amide, convert the amide to sodio, and then react the ditosylate compound with the desired A compound can be obtained.

As the N-vinylcarboxylic acid amide compound, N-vinylacetamide, N-vinylformamide, N-methylvinylacetamide and the like have been widely known, but have two N-vinyl structures in the molecule. The compound is hardly known. Particularly, a compound having two N-vinyl carboxylic acid amide groups was found by the above-mentioned inventors prior to the present invention, and a patent application was filed as Japanese Patent Application No. Hei 2-23239. Nothing was known other than methylene-bis (N-vinylcarboxylic acid amide). We have:
As a result of further studies on the production of a compound having a bis (N-vinylcarboxylic acid amide) structure, N, N'-alkylenebis (N-vinylcarboxylic acid amide) can be produced by a simple method, and the present invention The compound has excellent performance as a cross-linking agent for polymers, and has excellent cross-linking efficiency and chemical properties as compared with N, N'-methylenebis (N-vinylcarboxylic acid amide) previously proposed by the present inventors. The inventors have also found that the present invention is excellent in terms of mechanical stability, and have completed the present invention.

Specific examples of the compound according to the present invention include:
It is as follows. (1) Examples in which R ² is a C ₃ -C ₁₀ alkylene group N, N′-1,3-propylenebis (N-vinylacetamide) N, N′-1,4-butylenebis (N-vinylacetamide) N, N'-1,5-pentylenebis (N-vinylacetamide) N, N'-1,6-hexylenebis (N-vinylacetamide) N, N'-1,7-heptylenebis (N-vinylacetamide) N, N ' -1,8-octylenebis (N-vinylacetamide) N, N'-1,9-nonylenebis (N-vinylacetamide) N, N'-1,10-decylenebis (N-vinylacetamide) N, N'-diacetyl -N, N'-divinyl-1,3-
Butanediamine N, N'-diacetyl-N, N'-divinyl-2,5-
Hexanediamine N, N'-diacetyl-N, N'-divinyl-2,4-
Pentanediamine N, N'-diacetyl-N, N'-divinyl-2,2-
Diethyl-1,3-propanediamine N, N'-diacetyl-N, N'-divinyl-2,5-
Dimethyl-2,5-hexanediamine N, N'-diacetyl-N, N'-divinyl-2,4-
Dimethyl-2,4-pentanediamine N, N'-diacetyl-N, N'-divinyl-2,2-
Dimethyl-1,3-propanediamine N, N'-diacetyl-N, N'-divinyl-2-ethyl-1,5-hexanediamine N, N'-diacetyl-N, N'-divinyl-2-ethyl- 2-methyl-1,3-propanediamine N, N'-diacetyl-N, N'-divinyl-2-methyl-1,3-butanediamine N, N'-diacetyl-N, N'-divinyl-2- Methyl-1,5-pentanediamine N, N'-1,3-propylenebis (N-vinylformamide) N, N'-1,4-butylenebis (N-vinylformamide) N, N'-1,5- Pentylenebis (N-vinylformamide) N, N'-1,6-hexylenebis (N-vinylformamide) N, N'-1,7-heptylenebis (N-vinylformamide) N, N'-1,8 -Octylenebis (N-vinylformamide) N, N'-1,9-nonylenebis (N-vinylformamide) N, N'-1,10-decylenebis (N-vinylformamide) N, N'-diformyl-N, N '-Divinyl-1,3-
Butanediamine N, N'-diformyl-N, N'-divinyl-2,5-
Hexanediamine N, N'-diformyl-N, N'-divinyl-2,4-
Pentanediamine N, N'-diformyl-N, N'-divinyl-2,2-
Diethyl-1,3-propanediamine N, N'-diformyl-N, N'-divinyl-2,5-
Dimethyl-2,5-hexanediamine N, N'-diformyl-N, N'-divinyl-2,4-
Dimethyl-2,4-pentanediamine N, N'-diformyl-N, N'-divinyl-2,2-
Dimethyl-1,3-propanediamine N, N'-diformyl-N, N'-divinyl-2-ethyl-1,5-hexanediamine N, N'-diformyl-N, N'-divinyl-2-ethyl- 2-methyl-1,3-propanediamine N, N'-diformyl-N, N'-divinyl-2-methyl-1,3-butanediamine N, N'-diformyl-N, N'-divinyl-2- Methyl-1,5-pentanediamine

(2) Examples in which R ² is a polyoxyalkylene glycol chain N, N'-3-oxa-1,5-pentylenebis (N-
N, N'-3,6-dioxa-1,8-octylenebis (N-vinylacetamide) N, N'-3,6,9-Trioxa-1,11-undecylenebis (N-vinylacetamide) N, N'-3,6,9,12-tetraoxa-1,14-tetradecylenebis (N-vinylacetamide) N, N'-3-oxa-1,5-pentylenebis (N-
N, N'-3,6-dioxa-1,8-octylenebis (N-vinylformamide) N, N'-3,6,9-Trioxa-1,11-undecylenebis (N-vinylformamide) N, N'-3,6,9,12-tetraoxa-1,14-tetradecylenebis (N-vinylformamide)

N, N'-1,4-dimethyl-3-oxa-1,5-pentylenebis (N-vinylacetamide) N, N'-1,4,7-trimethyl-3,6-dioxa-1, 8-octylenebis (N-vinylacetamide) N, N'-1,4,7,10-tetramethyl-3,6,9
-Trioxa-1,11-undecylenebis (N-vinylacetamide) N, N'-1,4,7,10,13-pentamethyl-3,
6,9,12-tetraoxa-1,14-tetradecylenebis (N-vinylacetamide) N, N'-1,4-dimethyl-3-oxa-1,5-pentylenebis (N-vinylformamide) N, N'-1,4,7-trimethyl-3,6-dioxa-1,8-octylenebis (N-vinylformamide) N, N'-1,4,7,10-tetramethyl-3,6,9
-Trioxa-1,11-undecylenebis (N-vinylformamide) N, N'-1,4,7,10,13-pentamethyl-3,
6,9,12-tetraoxa-1,14-tetradecylenebis (N-vinylformamide)

(3) Examples in which R ² is a para- or meta-xylylene group para-xylylene bis (N-vinylacetamide) meta-xylylene bis (N-vinylacetamide) para-xylylene bis (N-vinylformamide) meta-xylylene bis (N- Vinyl formamide)

(4) Examples of a cyclohexane ring in which R ² has a methylene group at the 1,3- or 1,4-position N, N'-diacetyl-N, N'-divinyl-1,3-
Bisaminomethylcyclohexane N, N'-diacetyl-N, N'-divinyl-1,4-
Bisaminomethylcyclohexane N, N'-diformyl-N, N'-divinyl-1,3-
Bisaminomethylcyclohexane N, N'-diformyl-N, N'-divinyl-1,4-
Bisaminomethylcyclohexane

Although there is no intention to limit the use of the compounds of the present invention, as noted above, the compounds of the present invention are suitable for use as crosslinkers for preparing crosslinked polymers. In particular, it is suitable for use as a cross-linking agent for producing a cross-linked polymer containing an N-vinyl compound as one component of a monomer. More preferably, it is used as a crosslinking agent for producing a water-swellable gel (hydrogel) containing an N-vinylcarboxylic acid amide compound as a main component.

In producing a crosslinked polymer using the crosslinking agent of the present invention, for example, ethylene, vinyl acetate, acrylamide, N-methyl-N-vinylacetamide, etc.
Although any conventionally known vinyl compound can be used, it is particularly preferable to use N-vinylcarboxylic acid amide and / or N-vinylpyrrolidone as a part or all of the monomer to be used. It is possible to obtain a novel gel having features that are not united. In other words, although it is a hydrophilic and water-swellable gel, it has an affinity for certain organic solvents such as alcohol, dimethylformamide, and dimethylsulfoxide, and can absorb and swell these solvents. . Most of the conventional so-called water-absorbing polymers are based on polycarboxylic acids, and their water-absorbing ability largely depends on the electrolyte concentration solution in the aqueous solution. Furthermore, if polyvalent metal ions are present in the electrolyte, the swelling rate of the polymer cannot be prevented from significantly decreasing due to ionic crosslinking between polymer molecular chains.
In comparison, as disclosed in JP-A-1-302409, the gel produced using N-vinylcarboxylic amide as a monomer is hardly affected by the electrolyte in the solution. I knew it. However, as described above, when these N-vinyl compounds are used as monomers, a crosslinking agent having a good copolymerizability with them has not been known so far, while having a satisfactory gel strength, It was difficult to achieve a high crosslinking density and a high swelling ratio with respect to the solvent. The crosslinked polymer having a novel structure of the present invention is a unique polymer that can not be achieved with a gel synthesized using a conventional crosslinking agent, which simultaneously achieves gel strength, sufficient crosslink density, and swelling ratio with respect to a solvent. It has a characteristic.

As described above, according to the present invention, it is chemically stable, has excellent light fastness, has an excellent absorption capacity for organic solvents such as water and alcohol, and particularly has a metal salt in the system. Exhibits a high water absorption (organic absorption solvent) magnification for liquids in which inorganic and organic ions such as amines and carboxylic acids coexist, and as a result, swells and gels to make the coexisting liquid system non-fluid and solidified Slow release, adhesion, etc.
-Provided is a liquid absorbent having a wide range of applications in various fields utilizing the excellent features and functions of a resin obtained by crosslinking a trunk polymer mainly composed of vinylcarboxylic acid amide. For this reason, preferred resins have an average degree of polymerization of the main chain of 100 to 500,0.
00 and the crosslink density is 1/100 to 1 / 500,000.

Although the liquid absorbent of the present invention basically has a function of absorbing water and an organic solvent as described above, the water or organic solvent absorbed by the resin may be released depending on the external circumstances. Since the function of absorption-retention-release is reversible, these liquids have a regulating function (for example, in the case of an aqueous system, absorption (de) water, water retention, water supply,
Water regulation etc.). Moreover, since the resin of the present invention is chemically stable and excellent in light resistance, it can be repeatedly expressed many times, and the water retained in the resin has good reusability by plants and the like, and germination, germination Does not adversely affect roots and growth.

The resin that has absorbed the liquid itself swells and gels, but the system (liquid) to which the resin is added has a reduced fluidity as a whole and eventually becomes non-fluidized and solidified.
Therefore, the added system has shapeability, and the non-fluidized, solidified (shaped) system has a certain degree of elasticity from a very soft state depending on conditions. Various states can be taken up to the molded product, and various functions are exhibited according to each state. For example, in a relatively soft state, it has adhesion to an object, exhibits sealing properties and a certain kind of adhesiveness, and, in a molded article having elasticity, the above-mentioned water retention, water supply and the like. In addition, it absorbs vibration and shock, and exhibits sound absorption.

The liquid absorbent of the present invention can further utilize properties such as sustained release of components held in the gel, conductivity of water, and high specific heat (heat storage, cooling, heat retention). . The function of absorbing, retaining, (slowly) releasing, and non-fluidizing the liquid organic compound is one of the major features of the absorbent of the present invention together with the above-mentioned ionic resistance, and is a performance not found in conventional absorbents.

The functions of absorbing, releasing and controlling these liquids, releasing them slowly, reducing the fluidity of the added system, solidifying,
Various functions such as shaping properties or adhesion to the outside world, covering properties, etc. are so-called causes and effects, and a series of closely related phenomena are viewed from various viewpoints. Absorption-gelation. Therefore, in the present invention, the term liquid absorbent should not be interpreted in a narrow sense only in terms of simply absorbing liquid, and as a result of the use of the crosslinked N-vinylcarboxylic acid amide resin as described above ( It also means various functions, actions, and phenomena that are provided.

Such various functions (basically, absorbents for water and organic solvents) are particularly useful for the homo- or copolymer main chain containing 50 to 100 mol% of the N-vinylcarboxylic acid amide component of the above formula [2]. It is brought about by using a cross-linked N-vinylcarboxylic acid amide resin obtained by cross-linking with a cross-linking agent,
With respect to the component a (N-vinylcarboxylic acid amide component) and the component b (copolymerization component) of the repeating unit represented by the above general formula, typical examples of the respective monomers are specifically exemplified. And the like.

Component a: N-vinylformamide, N-vinylacetamide, N-methyl-N-vinylformamide, N-methyl-N-vinylacetamide, etc., with N-vinylacetamide being particularly preferred.

Component b: acrylic acid, methacrylic acid (hereinafter collectively referred to as (meth) acrylic acid) or their alkali metal salts such as sodium salt and potassium salt;

The methyl ester, ethyl ester, propyl ester, butyl ester, pentyl ester,
Alkyl esters such as hexyl ester, heptyl ester, octyl ester, nonyl ester, decyl ester, stearyl ester, palmityl ester;

Hydroxy lower alkyl esters such as hydroxyethyl ester, hydroxypropyl ester and hydroxybutyl ester;

The lower group substituted by a lower alkylamino group such as dimethylaminomethyl ester, dimethylaminoethyl ester, dimethylaminopropyl ester, dimethylaminobutyl ester, diethylaminomethyl ester, diethylaminoethyl ester, diethylaminopropyl ester and diethylaminobutyl ester Alkyl esters;

The trimethylammonioethyl ester halide, trimethylammoniopropyl ester halide, triethylammonioethyl ester halide,
Lower alkyl esters substituted with a quaternary ammonium group such as triethylammoniopropyl ester halide;

The amide;

Amides substituted by lower alkylamino groups such as dimethylaminomethylamide, dimethylaminoethylamide, dimethylaminopropylamide, dimethylaminobutylamide, diethylaminomethylamide, diethylaminoethylamide, diethylaminopropylamide and diethylaminobutylamide ;

Lower alkylamides substituted with quaternary ammonium groups such as trimethylammonioethylamide amide halide, trimethylammoniopropylamide halide, triethylammonioethylamide halide, triethylammoniopropylamide halide;

The sulfomethylamide, sulfoethylamide, sulfopropylamide, sulfobutylamide, sodium sulfomethylamide, sodium sulfoethylamide, sodium sulfopropylamide, sodium Lower alkyl amides substituted with sulfonic acids or alkali metal sulfonic acids such as sodium sulfobutylamide, potassium sulfomethylamide, potassium sulfoethylamide, potassium sulfopropylamide, and potassium sulfobutylamide;

Acrylonitrile;

N-vinyl-2-pyrrolidone;

Vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether and butyl vinyl ether;

Vinyl ketones such as methyl vinyl ketone and ethyl vinyl ketone;

Lower vinyl carboxylate such as vinyl acetate and vinyl propionate;

Allyl sulfonic acid such as allyl sulfonic acid, sodium allyl sulfonate, potassium allyl sulfonate and the like or alkali metal salts thereof;

Maleic acid, sodium maleate, potassium maleate, fumaric acid, sodium fumarate,
Itaconic acid, sodium itaconate, potassium itaconate, etc.

Among these, (meth) acrylic acid,
Sodium (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth)
Acrylate, hydroxybutyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, trimethylaminoethyl (meth) acrylate, acrylamide, sulfopropylacrylamide, sulfobutylacrylamide, sodium sulfopropylacrylamide, sodium sulfate Phobutyl acrylamide,
Acrylonitrile, methyl vinyl ether, ethyl vinyl ether, methyl vinyl ketone, ethyl vinyl ketone, vinyl acetate, sodium allyl sulfonate, N-
Preferred are vinyl-2-pyrrolidone, maleic acid, sodium maleate, itaconic acid, sodium itaconate, and the like.

In the case of a copolymer, the component a preferably contains at least 50 mol% as described above. Below this, the ionic resistance, absorption of organic compounds, and light resistance characteristic of the absorbent of the present invention are obtained. Not fully demonstrated. Since the preferred range of the copolymer composition varies depending on the type of liquid to be absorbed, particularly the type and concentration of coexisting solute, it cannot be specified unconditionally, but is preferably 50 to 99: 1 to 50 in molar ratio.

As the crosslinking agent, the bis (N-vinylcarboxylic acid amide) compound represented by the above general formula [1] is used.
The specific compounds are as exemplified above.

Of these, N, N'-1,4-butylenebis (N-vinylacetamide), N, N'-1,6
-Hexylenebis (N-vinylacetamide), N,
N'-1,10-decylenebis (N-vinylacetamide), N, N'-3-oxa-1,5-pentylenebis (N-vinylacetamide), N, N'-3,6-dioxa-1,8 -Octylenebis (N-vinylacetamide), N, N'-p-xylylenebis (N-vinylacetamide), N, N'-diacetyl-N, N'-divinyl-1,4-bisaminomethylcyclohexane and the like are particularly preferred. Are listed.

The liquid absorbent according to the invention further comprises:
A general crosslinking agent having two or more unsaturated groups in the molecule may be used in combination with the bis (N-vinylcarboxylic acid amide) compound at a molar ratio of 9 or less as the crosslinking agent. Examples of such crosslinking agents include N, N'-methylenebisacrylamide, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate,
A compound having a plurality of acrylic groups and / or methacryl groups, such as polyethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, and pentaerythritol tri (meth) acrylate;
Triallyl isocyanurate, trimethylolpropane diallyl ether, diallyl phthalate, diallyl maleate, diallylamine, triallyl trimellitate, compounds having two or more allyl groups such as tetraallyl pyromellitic acid, and others, divinylbenzene, divinyl ether, Compounds having two or more unsaturated groups in one molecule, such as allyl (meth) acrylate. Although it is not clear why the use of a plurality of cross-linking agents in combination provides an advantage, monomers having different reactivity and a cross-linking agent having good copolymerizability are simultaneously added to the system. It is presumed that by doing so, the crosslinking points are uniformly introduced.

The amount of the crosslinking agent used is 2 × 10 ^-4 to 1 mol%, preferably 2.5 × 10 ⁴ mol%, based on the (co) polymerization component.
^{-4 to} 0.2 mol%, particularly preferably 5 × 10 ^-4 to 1 × 10 ^-2 mol%. When the amount of the crosslinking agent used is more than 1 mol% based on the (co) polymerization component, the crosslinking density of the obtained resin becomes too high, so that the absorption performance of the resin is remarkably reduced. If the amount is less than 10 ^-4 mol%, the proportion of the polymer chains that are not crosslinked increases, and the polymer chains are easily dissolved in water or an organic solvent, so that the performance expected as an absorbent cannot be exhibited.

The polymerization process is not particularly limited, but it is usually preferable to employ a method such as an aqueous solution polymerization method, a reversed phase suspension polymerization method or a reversed phase emulsion polymerization method. For example, in the aqueous solution polymerization method, a monomer component and a cross-linking agent are uniformly dissolved in a solvent such as water or a hydrophilic organic solvent which can be uniformly mixed with water, or a mixed solvent thereof, and then deaerated in vacuum or nitrogen gas or carbon dioxide gas. After removing the dissolved oxygen in the system by replacement with an inert gas such as the above, a polymerization initiator is added and reacted. The polymerization initiation temperature is usually about −10 to 60 ° C., and the reaction time is 1 to
About 10 hours.

Representative examples of the hydrophilic organic solvent include lower alcohols such as methyl alcohol, ethyl alcohol and propyl alcohol, cyclic ethers such as tetrahydrofuran and dioxane, acetone, acetonitrile, dimethylformamide, dimethylacetamide, and the like. Dimethyl sulfoxide and the like. Among these, tetrahydrofuran, acetonitrile,
Dimethylformamide, dimethylacetamide, dimethylsulfoxide and the like are preferred.

As the polymerization initiator, peroxides, organic and inorganic peracids or salts thereof which are uniformly dissolved in a solvent,
Redox-based azobis-based compounds alone or in combination with a reducing agent are used, and typical examples thereof include the following.

T-butyl peroxide, t-amyl peroxide, cumyl peroxide, acetyl peroxide, propionyl peroxide, benzoyl peroxide, benzoyl isobutyryl peroxide, lauroyl peroxide, t-butyl hydroperoxide, cyclohexyl hydro Peroxide, tetralin hydroperoxide, t-butyl peracetate, t-butyl perbenzoate, bis (2
-Ethylhexyl peroxydicarbonate), 2,2
-Azobis i-butyronitrile, phenylazotriphenylmethane, 2,2-azobis (2-amidinopropane) dihydrochloride, 2,2-azobis [2- (5-methyl-
2-imidazolin-2-yl) propane] dihydrochloride,
2,2-azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride, sodium persulfate, potassium persulfate, ammonium persulfate, hydrogen peroxide, persulfate and triethylamine, triethanolamine, dimethylaniline And the like with a tertiary amine.

Among these, t-butyl peroxide, benzoyl peroxide, 2,2-azobis i
-Butyronitrile, 2,2-azobis (2-amidinopropane) dihydrochloride, 2,2-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloride, 2,2-azobis [2- (2-imidazoline-2-
Il) propane] dihydrochloride, sodium persulfate, potassium persulfate or ammonium persulfate alone or in combination with these persulfates and tertiary amines such as triethylamine, triethanolamine or dimethylaniline.

The amount of the polymerization initiator used is 0.0005 to 5 mol%, preferably 0.001 to 5 mol%, based on the (co) polymerization component.
To 1 mol%, particularly preferably 0.005 to 0.5 mol%. When the amount of the polymerization initiator used is more than 5 mol% based on the (co) polymerization component, the degree of polymerization of the main chain polymer chains does not increase, and the proportion of non-crosslinked polymer chains increases. The performance expected as an absorbent cannot be exhibited because it is easily dissolved in water or an organic solvent.On the other hand, when it is less than 0.0005 mol%, the reaction rate of the polymerization reaction does not increase and the amount of residual monomer increases. is there.

The reaction product is in the form of a gel containing the solvent used in the reaction, and is usually pulverized with a rotary cutter or the like.
The solvent is removed by a method such as heating or decompression, dried, and pulverized and classified to obtain a powder having a particle size of about 50 μm to 1 mm.

In the reverse phase suspension polymerization method and the reverse phase emulsion polymerization method, a monomer component and a crosslinking agent are uniformly dissolved in water, and the resulting solution is suspended or emulsified in an organic solvent which is not uniformly mixed with water. Let it react. As the polymerization initiator, not only a water-soluble polymerization initiator but also a polymerization initiator soluble in an organic solvent is used. Therefore, in addition to the above, for example, hexane, cyclohexane, heptane, octane, benzene,
Hydrocarbons such as toluene, xylene and ethylbenzene, halogenated hydrocarbons such as hydrogen tetrachloride and dichloroethane, and mineral oils such as Isopar are also used.

In the inverse emulsion polymerization method, a surfactant is used as a dispersant, and a protective colloid is used together if necessary. Representative examples thereof include, for example, sorbitan monostearate, sorbitan monopalmitate,
Examples include polyvinyl alcohol, methyl cellulose, ethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, carboxyethyl cellulose, and the like.

The removal of dissolved oxygen in the system, the treatment of the reaction product, and the like are the same as described above. The reaction conditions are not necessarily limited, but are generally as follows. Amount of solvent used: Equivalent to 20-fold, preferably equivalent to 10-fold, particularly preferably equivalent to 5-fold, the amount of the polymerization initiator used; 0.0005 to 5 mol%, preferably based on the monomer component, of the monomer component 0.001-1
Mol%, particularly preferably 0.005 to 0.5 mol%, polymerization initiation temperature: about 10 to 90 ° C., and reaction time: about 1 to 10 hours.

The molecular structure of the resin thus obtained was such that a linear polymer comprising a homopolymer of N-vinylcarboxylic amide or a copolymer with another copolymerization component formed a main chain, which was crosslinked by a crosslinking agent. Has a three-dimensional structure,
Mainly, the molecular size and the state of cross-linking, that is, the molecular weight of the main chain and the cross-link density largely control the function as the liquid absorbent of the present invention. For example, in theory, the main chain can be made as large as possible, and the crosslink density can be made as small as possible to increase the liquid absorption capacity. However, the liquid absorption capacity has its own limit, and the distance between crosslinks can be increased. In this case, the physical strength of the gel formed by absorbing the liquid is remarkably reduced, and the number of molecules that do not participate in cross-linking increases to increase the solubility. Therefore, the degree of polymerization of the main chain: 500,000 to 100, preferably 400,000 to 1,000, particularly preferably 200,000 to 1
0,000, and crosslinking density: 1 / 500,000 to 1/100, preferably 1 / 300,000 to 1/1000, particularly preferably 1
It is important to be in the range of / 200,000 to 1 / 10,000. In the case where the main chain is a copolymer, there is a slight difference in the structure due to the difference in reactivity of the copolymer component.
When acrylamide, maleic acid, or the like is used as a copolymer component, alternating copolymerization often occurs depending on the molar ratio of the charged reactants. When acrylic acid or the like is used, block copolymerization is often used, and when vinyl acetate or the like is used, random copolymerization is often used. However, the difference in the structure of the main chain copolymer due to the difference in the reactivity of these copolymer components may cause a characteristic function to be added to each of the use examples, but the liquid absorption of the present invention as a whole It is not essential in the agent.

The crosslinked N-vinylcarboxylic acid amide resin (liquid absorbent) of the present invention has a diameter of 50 μm as described above.
It can be obtained in powder form of about 1 mm, but in the state of absorbing liquid, it is in the form of beads or dispersion, cream, paste-like viscous material, etc. It is also formed by itself to form a string, film, sheet, plate It is used in various shapes and forms in combination with various bases (materials).

The liquid absorbent containing a crosslinked N-vinylcarboxylic acid amide resin of the present invention as a main component is basically composed of water and an organic solvent having ionic resistance, chemical stability and light resistance as described above. The superior absorption function is mainly used for liquid absorption, release and control functions and sustained release properties, decrease in fluidity to the added system, solidification, shapeability or adhesion to the outside world, sealing property and a kind of Adhesive, covering,
A molded article having elasticity absorbs vibration and impact in addition to the above-described water retention, water supply, etc., and exhibits sound absorption. Furthermore, the sustained release of the components held in the gel and the conductivity of water,
Properties such as high specific heat (heat storage, cooling, heat retention) are also available.

In the liquid absorbent of the present invention, in particular, a crosslinked product of sodium polyacrylate, which is conventionally represented by a water-absorbing polymer, is incorporated into a liquid to be absorbed by inorganic or organic compounds such as metal salts, amines and carboxylic acids. In the case where ions coexist, there is a disadvantage that the water absorption performance is remarkably impaired. On the other hand, the water absorption performance is hardly affected by the coexistence of ions. In addition, the water absorbed and retained in the resin has good reusability by plants and the like, and does not adversely affect germination, rooting, and growth. Applications that take advantage of such features, for example, general farmland,
In addition to forests, of course, relatively salty soil such as desert greening, or medium containing inorganic salts or fertilizers such as tissue culture or artificial cultivation, water solution for artificial cultivation (water supply); sanitary goods (diapers,
Absorbent for body fluids (urine, menstrual blood) with high salt content such as napkins and tampons; absorbent for water with high calcium content such as concrete curing and cement modifier; non-fluidizing agent for deliquescent of calcium chloride-based hygroscopic agent A metal salt solution dispersant (composite forming agent with a metal compound) for producing ultrafine ceramics;

Further, in the liquid absorbent of the present invention, in particular, the liquid to be absorbed of a crosslinked product of sodium polyacrylate, which is a typical water-absorbing polymer, is limited to water or a mixture of water and some lower alcohols. On the other hand, it can also absorb water, various organic solvents or mixtures thereof. Specific examples of typical organic solvents that can be absorbed include, for example, the following, which are generally referred to as relatively polar solvents.

Methanol, ethanol, 1-propanol, 1-butanol, 2-butanol, isobutyl alcohol, isoamyl alcohol, cyclopentanol,
Allyl alcohol, 1,1,1,3,3,3-hexafluoro-2-propanol, 2-methoxyethanol,
2-ethoxyethanol, 2-butoxyethanol, 2
Alcohols such as aminoethanol, ethylene glycol, trimethylene glycol, propylene glycol, 1,4-butanediol, 1,3-butanediol, 2,3-butanediol, triethylene glycol and glycerin; phenol, cresol and the like Phenols;
Others include formamide, acetic acid, 2-pyrrolidinone, dimethylsulfoxide, pyridine and the like. Further, they have no or very poor absorption by themselves, but can be absorbed in a mixed system, for example, water and N , N-dimethylformamide, phenol, acetone, tetrahydrofuran or dioxane, etc .; water-organic solvent system; ethanol-
A mixed solvent system of organic solvents such as acetone, ethanol-chloroform, ethanol-benzene, ethanol-ethyl acetate, methanol-methylene chloride, and ethyl acetate-acetic acid is shown.

The liquid absorbent of the present invention can be used in such a wide range.
Although the reason for absorbing the solvent is not always clear, the present invention
-Linked N-vinyl carboxy as a main component of liquid absorbent
Strength of interaction between acid amide resin and absorbable solvent system
As a measure, the high polarity of the solvent system can be considered. General
In addition, dielectric constant (ε), dissolution
Degree parameter (δ), solvent polarity parameter (E_Tvalue
Or Z value) are known, but these parameters
As a result of various analyzes using a
E in one solvent_TValue is 45 or more, and in the mixed solvent
E of the solvent system _TValue is 43 or more, and conversely, less than this value
Was found to be hardly absorbed. Follow
As an organic solvent that can be absorbed by the liquid absorbent of the present invention,
Is E in a single solvent_TValue of 45 or more,
E of medium system_TIt can be said that the value is 43 or more. Especially,
E_TThe relationship between the value and the absorbency applies only to a single solvent,
E for any mixed solvent_TValue 50 or more, more preferably
More than 53.

Specific examples of typical uses other than those described above include, for example, the following.
Of course, these are merely examples, and the use of the liquid absorbent of the present invention is not limited to the following, and it can be used in a wide variety of fields and products by utilizing the above functions. It is. Food products (freshness preservation products, dehydration, water retention, water supply, moisture regulators); agricultural and horticultural products (soil conditioners, seedlings and cultivation base materials, plant preservation (planting, desert greening, etc.) water preservation and supply agents, seeds Formulation, anti-frost and dew-prevention agent (material)); Household and architectural moisture absorption, dew-prevention, anti-drip agent; Communication cable, waterproofing of equipment, dehydration of water-stopping agent (material), water retention, water supply,
Water regulators; various sustained-release preparations for oral and enteral pharmaceuticals, health foods, feed additives, agricultural chemicals, fertilizers, etc .; medical supplies (pastes, mucosal preparations, suppositories); Toiletries and sanitary products (paper diapers, sanitary napkins, and other excrement treatment agents); civil engineering, construction, household,
Various industrial sealing agents, putty, paint assistants, adhesive tapes, salt damage and dust inhibitor (materials); adhesion, covering bases and assistants; civil engineering waterproofing agents, sandbags, stomatal shields and mines,
Drilling aids and lubricants for foundations such as tunnels, buildings and piers; Household air fresheners, deodorants, fire extinguishers, heat storage agents (cooling, heat retention);
Batteries, electrodes, sensor members; electrical components such as antistatic agents (materials); conductivity improvers (materials); heat insulation (convection) prevention, vibration absorption, sound absorbing materials, packing; cosmetics (scrub face wash, packing agents, fragrances) Agent); decrease in fluidity, solidification, or excipient in a contact lens cleaning agent or the like.

Specific usage of the liquid absorbent of the present invention,
The amount of use is somewhat different depending on each application, so it cannot be said unconditionally. However, in principle, it does not greatly differ from general and standard specifications in each application. However, because of its excellent functions and effects, it is possible to expect use cases that have never been seen before,
Needless to say, the amount of use can be reduced to achieve the same effect.

[0104]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but it goes without saying that the technical scope of the present invention is not limited to these Examples.

[0105]Example 1: N, N'-1,4-butylenebis
Production of (N-vinylacetamide) (Part 1) 6.08 g (80 mmol) of N-vinylacetamide was
To a solution dissolved in 30 ml of Lumamide, add sodium hydride
(60% mineral oil dispersion) 4.0g (100mmol)
Was. Vigorous bubbling into an almost uniform pale yellow solution,
To this, 4.32 g (20 mmol) of 1,4-butanedibromide was added.
And stirred at room temperature for 12 hours. The solution is distilled under reduced pressure.
After removing, 30 ml of water was added and neutralized with 1N hydrochloric acid. this
The aqueous layer was extracted several times with toluene, and the toluene layer was evaporated.
Was. Evaporate the remaining colorless liquid through a silica gel column with ethyl acetate.
/ N-hexane (100/4 volume ratio) as a developing solution
After recrystallization from water, a white needle with a melting point of 42 ° C was formed.
Crystals were obtained in a yield of 8%. Table 1B shows the physical properties of this compound.
Show.

[0106]Example 2: N, N'-1,4-butylenebis
Production of (N-vinylacetamide) (Part 2) 1.02 g (12 mmol) of N-vinylacetamide
In a solution dissolved in 20 ml of Lumamide, add sodium hydride
(60% mineral oil dispersion) 0.50g (13mmol)
Was. Vigorous bubbling into an almost uniform pale yellow solution,
1.82 g of 1,4-butanediol tosylate (5 mm
ol) and stirred at room temperature for 12 hours. This solution under reduced pressure
After evaporating the solvent, add 20 ml of water and neutralize with 1 N hydrochloric acid.
Was. The aqueous layer was extracted several times with diethyl ether,
The toluene layer was evaporated. Remove the remaining colorless liquid
Ethyl acetate / n-hexane (100/4 volume)
Ratio) as a developing solution and then recrystallized from water
By filtration, white needle crystals having a melting point of 42 ° C. were obtained in a yield of 83%. This transformation
Table 1B shows the physical property values of the compound.

[0107]Example 3: N, N'-1,10-decylene bis
Production of (N-vinylacetamide) In Example 2, 1,4-butanediol ditosylate was
Same as above except that 1,10-decanediol ditosylate was used.
Was performed. Yield of oily colorless liquid at room temperature
63% was obtained. Table 1H shows the physical properties of this compound.

Example 4: N, N'-3-oxa-1,5-pe
The same operation was performed except that 1,4-butanediol ditosylate was changed to diethylene glycol ditosylate in Production Example 2 of nethylene bis (N-vinylacetamide) . Yield of oily colorless liquid at room temperature
43% obtained. Table 1I shows the physical properties of this compound.

Example 5: N, N'-3,6-dioxa-1,
The same operation was performed as in Production Example 2 of 5-pentylenebis (N-vinylacetamide) except that 1,4-butanediol ditosylate was replaced with triethylene glycol ditosylate . At room temperature, an oily colorless liquid was obtained with a yield of 57%. Table 1J shows the physical properties of this compound.

Example 6: para-xylylenebis (N-vinyl
Acetamide) was prepared in the same manner as in Production Example 1 except that 1,4-dibromobutane was changed to para-xylylene chloride.
A white solid with a melting point of 121-124 ° C. was obtained in a yield of 28%. Table 10 shows the physical properties of this compound.

Example 7: N, N'-diacetyl-N, N'-
Divinyl-1,4-bis (aminomethyl) cyclohexa
A similar operation was performed except that 1,4-butanediol ditosylate was changed to 1,4-cyclohexanedimethanol ditosylate (trans form) in Production Example 2 of styrene. Melting point
131 ° C., colorless and transparent crystals were obtained in a yield of 39%. Table 1Q shows the physical properties of this compound.

Table 1 shows the physical properties of other bis (N-vinylcarboxylic acid amide) compounds produced in the same manner.

[0113]

[Table 1]

[0114]

[Table 2]

[0115]

[Table 3]

[0116]

[Table 4]

[0117]Example 8: N, N'-1,4-butylenebis
(N-vinylacetamide) as a crosslinking agent
Production of crosslinked polymer of ri (N-vinylacetamide) In a bath maintained at 30 ° C, equipped with a nitrogen inlet pipe, thermometer, and exhaust pipe
In a three-necked 200 ml separable flask,
40 g of luacetamide, N, N'-1,4-butylenebis
(N-vinylacetamide) 2.0mg dissolved in 150g water
And degas by introducing nitrogen into the system at 1 liter / minute for about 30 minutes
did. Then, 2,2'-azobi dissolved in 10 ml of degassed water
(2-amidinopropane) dihydrochloride (120 mg)
Let stand for hours. The resulting gel is cut with a mincer and
After washing with a ton, vacuum drying was performed at 80 ° C. for 12 hours. Obtained
Dried gel is water, ethanol, dimethylformamide, etc.
Swells and has no soluble part, maintaining gel shape
Was something.

[0118]Example 9: N, N'-1,10-decylene bis
(N-vinylacetamide) as a crosslinking agent
Production of crosslinked polymer of ri (N-vinylacetamide) In Example 8, N, N'-1,4-butylenebis (N-
Vinylacetamide) instead of N, N'-1,10-de
Except for using silenebis (N-vinylacetamide)
The same operation was performed. The resulting dried gel has no soluble part.
And the shape of the gel was maintained.

Example 10: N, N'-3-oxa-1,5-pe
Nintylene butylene bis (N-vinylacetamide)
Of poly (N-vinylacetamide) used as a crosslinking agent
In Production Example 8 of the crosslinked polymer , N, N'-1,4-butylenebis (N-
The same operation was performed except that N, N'-3-oxa-1,5-pentylenebutylenebis (N-vinylacetamide) was used instead of (vinylacetamide). The obtained dried gel had no soluble portion and maintained the gel shape.

Example 11: N, N'-3,6-dioxa-1,
Crosslinking 8-octylene bis (N-vinylacetamide)
Of poly (N-vinylacetamide) used as an agent
In Production Example 8 of the bridge polymer , N, N'-1,4-butylenebis (N-
The same operation was performed except that N, N'-3,6-dioxa-1,8-octylenebis (N-vinylacetamide) was used instead of (vinylacetamide). The obtained dried gel had no soluble portion and maintained the gel shape.

[0121]Example 12: N, N'-para-xylylenebis
(N-vinylacetamide) as a crosslinking agent
Production of crosslinked polymer of ri (N-vinylacetamide) In Example 8, N, N'-1,4-butylenebis (N-
Vinylacetamide) instead of N, N'-para-xy
Except using rylene bis (N-vinylacetamide)
The same operation was performed. The resulting dried gel has no soluble part.
And the shape of the gel was maintained.

Example 13: N, N'-diacetyl-N, N'-
Divinyl-1,4-bis (aminomethyl) cyclohexa
(N-vinylacetamide)
C ) in Production Example 8 of the crosslinked polymer of N, N'-1,4-butylenebis (N-
Vinylacetamide) instead of N, N'-diacetyl-N, N'-divinyl-1,4-bis (aminomethyl)
The same operation was performed except that cyclohexane was used.
The obtained dried gel had no soluble portion and maintained the gel shape.

[0123]Example 14: N, N'-1,4-butylenebis
Water using (N-vinylacetamide) as a crosslinking agent
/ Poly (N-vinyl)
Production of cross-linked polymer In a bath maintained at 40 ° C, install a nitrogen inlet tube, thermometer, and exhaust tube.
In a four-necked 1-liter separable flask,
Vinylacetamide 120g, N, N'-1,4-butyle
Nbis (N-vinylacetamide) 120 mg, hydroxy
2.4 g of ethylcellulose (Fuji Chemical)
Dissolved in 180 g of exchanged water and nitrogen was introduced into the system at 1 liter / min.
It was introduced for about 1 hour and degassed. Separately, cyclo degassed in advance
0.6 g of sorbitan monostearate in 300 g of hexane
After dispersing, heating to about 40 ° C and dissolving,
Transfer to a separable flask containing
did. Then, 2,2'-azobi dissolved in 10 ml of degassed water
(2-amidinopropane) dihydrochloride (360 mg)
The mixture was stirred at 0 rpm for 6 hours. After heating and stirring, filter the contents.
Separately, the solid content was vacuum-dried at 80 ° C. for 12 hours. The resulting dried
The fine particles are in the form of beads with a particle size of 100 to 500 μm
It was a good gel having a melting part of less than 10% by weight.

[0124]Example 15: N, N'-1,4-butylenebis
(N-vinylacetamide) as a crosslinking agent
Production of cross-linked polymer of poly (N-vinylformamide) In a bath maintained at 40 ° C, install a nitrogen inlet tube, thermometer, and exhaust tube.
In a three-necked 200 ml separable flask,
40 g of ruformamide, N, N'-1,4-butylenebis
Dissolve 8.0 mg of (N-vinylacetamide) in 150 g of water
And degas by introducing nitrogen into the system at 1 liter / minute for about 30 minutes
I do. Then, 2,2'-azobi dissolved in 10 ml of degassed water
(2-amidinopropane) dihydrochloride (120 mg)
Let stand for a while. The resulting gel is cut with a mincer and
After washing with tons, vacuum drying at 80 ° C. for 12 hours. Obtained
Dried gel has no soluble part and maintains the shape of the gel.
there were.

Example 16: N, N'-1,4-butylenebisN
Poly (N-vinyl-2-pi) using VA as a crosslinking agent
Rolidone) in Preparation Example 15 for the cross-linked polymer , N-vinylacetamide was replaced with N-vinylacetamide.
The same operation was performed except that vinylpyrrolidone was used. The obtained dried gel had no soluble portion and maintained the gel shape.

Example 17: N, N'-1,4-butylenebisN
N-vinylacetamide using VA as a crosslinking agent
In Preparation Example 8 of sodium acrylate copolymer gel , instead of N-vinylacetamide 40 g,
The same operation was performed except that a mixture of 36 g of N-vinylacetamide and 4 g of sodium acrylate was used. The obtained dried gel had no soluble portion and maintained the gel shape.

[0127]Example 18: N, N'-1,4-butylenebis
(N-vinylacetamide) and N, N ' Using methylene bisacrylamide as a crosslinking agent,
N-vinylacetamide / sodium acrylate / 2-Ac
Lilamide-2-methylpropanesulfonic acid sodium salt
Production of original copolymer gel In a bath maintained at 30 ° C, equipped with a nitrogen inlet pipe, thermometer, and exhaust pipe
In a three-necked 200 ml separable flask,
16.8 g of luacetamide, 15.2 g of sodium acrylate and 2-
Acrylamide-2-methylpropanesulfonate
8 g, N, N'-1,4-butylenebis (N-vinyl
Acetamide) 1.0 mg, N, N'-methylenebisacrylic
Dissolve 1.0mg of Lamide in 150g of water
Degas by introducing nitrogen into the system for about 30 minutes. Then degassed water
2,2'-azobis (2-amidinopro) dissolved in 10 ml
Bread) Add 120 mg of dihydrochloride and let stand for 12 hours. Obtained
The gel is cut with a mincer, washed with acetone, and then
Vacuum dry at 12 ° C for 12 hours. The resulting dry gel is water, ethanol
Swells in ethanol, dimethylformamide, etc.
There was no melting part and the gel shape was maintained.

Comparative Example 1 In Example 8, N, N'-1,4-butylenebis (N-
The same operation was performed except that N, N'-methylenebisacrylamide was used instead of (vinylacetamide). The obtained polymer was soluble in water.

Comparative Example 2 In Example 8, N, N'-1,4-butylenebis (N-
The same operation was performed except that N, N'-methylenebis (N-vinylacetamide) was used instead of (vinylacetamide). The obtained polymer was soluble in water.

Comparative Example 3 In Example 8, instead of 40 g of N-vinylacetamide,
7.4 g of N-vinylacetamide and 32.6 of sodium acrylate
The same operation was performed except that the mixture of g was used. The obtained polymer was soluble in water.

Comparative Example 4 The same operation was performed as in Example 17 except that N, N'-methylenebisacrylamide was used instead of N, N'-1,4-butylenebis (N-vinylacetamide). . The obtained polymer was soluble in water.

Example 19: Poly (N-vinylacetamide) ge
Le poly prepared in swelling ratio Example 8 in an organic solvent of (N- vinylacetamide) gels, the swelling ratio in various organic solvents shown in Table 2. As a comparative example, the swelling ratio of sodium polyacrylate gel is shown in the table. The swelling ratio was determined by dispersing 0.5 g of gel pulverized to 32 to 100 mesh in 200 ml of each solvent, allowing the mixture to stand for 2 hours, filtering through a 200-mesh wire net, and weighing the weight of the swollen gel. However, the swelling ratio is given by the following equation.

Swelling ratio = (weight of swollen gel−weight of dry gel) / (weight of dry gel)

[0134]

[Table 5]

Example 20: Poly (N-vinylacetamide) gel
Table 3 shows the swelling ratio for poly (N- vinylacetamide) various aqueous electrolyte solution of the gel was measured using the same method as swelling ratio Example 19 for the electrolyte solution Le. As a comparative example, the swelling ratio of sodium polyacrylate gel is shown in the table.

[0136]

[Table 6]

*) Composition of artificial urine (component amount in 1 liter of artificial urine) Urea: 20 g, sodium chloride: 8.2 g, potassium sulfate:
2.04 g, magnesium sulfate: 1.14 g, calcium chloride: 0.64 g.

Example 21: Poly (N-vinylacetamide) ge
Prepared in weather resistance Example 8 in a swollen state Le poly (N- vinylacetamide) gels, the results of evaluation of the weather resistance at the swollen state are shown in Table 4.
As a comparative example, the results of evaluation of the weather resistance of sodium polyacrylate gel are shown in the same table. The evaluation of the weather resistance was performed as follows.

Evaluation of weather resistance (UV irradiation test) 100 to 400 mg of the gel was weighed in a 100 ml beaker, swollen with ion-exchanged water, and then subjected to a 100 V, 15 W UV lamp.
It was left under 30 cm. After a certain time, the swelling ratio of the gel was measured.

[0140]

[Table 7]

Example 22 A glass reactor was charged with 750 g of water, 200 g (2.4 mol) of N-vinylacetamide, and N, N'-1,4 as a crosslinking agent.
1.0 g of butylenebis (N-vinylacetamide) was added and dissolved, and dissolved oxygen was removed in advance in a constant temperature bath at 30 ° C. with nitrogen gas. Then, 2,2′-azobis (2-amidino) was used as a polymerization initiator. Propane) dihydrochloride 0.4g to water 49.6g
, And reacted for 16 hours under nitrogen flow.
The gel-like reaction product was taken out, finely divided, dehydrated with acetone, and dried at 105 ° C. for 5 hours. The dried product was pulverized and classified to obtain a 48 to 100 mesh product. The average degree of polymerization of this resin was 20,000, and the crosslink density was 1 / 16,000.

Example 23 A resin was obtained in exactly the same manner as in Example 22, except that N-vinylacetamide was replaced with the same weight of N-vinylformamide. The average degree of polymerization of this resin is 19,000 and the crosslink density is 1 /
19,000.

Example 24 N-Vinylacetamide to N-methyl-N-
The reaction was carried out in exactly the same manner as in Example 22 except that vinylformamide was used, to obtain a resin. The average polymerization degree of this resin was 19,000, and the crosslink density was 1 / 19,000.

Example 25 N-Vinylacetamide to N-methyl-N-
The reaction was carried out in exactly the same manner as in Example 22 except that vinylacetamide was used, to obtain a resin. The average polymerization degree of this resin was 15,000, and the crosslink density was 1 / 14,000.

Example 26 200 g of N-vinylacetamide to 160 g (1.88 mol) of N-vinylacetamide and 40 g of sodium acrylate
(0.43 mol), except that the reaction was carried out in the same manner as in Example 22 to obtain a resin. The average degree of polymerization of this resin was 22,000, and the crosslink density was 1 / 16,000.

Examples 27 to 49 A resin was obtained in exactly the same manner as in Example 26 except that the same weight of various copolymerized monomer components was used in place of the non-polymerized monomer component sodium acrylate. These are summarized in Table 5.

[0147]

[Table 8]

Example 50 The same as Example 26 except that N, N'-1,4-butylenebis (N-vinylacetamide) was used as the crosslinking agent and the same molar amount of N, N'-hexylenebis (N-vinylacetamide) was used. The same reaction was performed to obtain a resin. The average degree of polymerization of this resin was 18,000, and the crosslink density was 1 / 16,000.

Examples 51 to 55 The reaction was carried out in exactly the same manner as in Example 26 except that the same molar amounts of various crosslinking agents were used instead of N, N'-1,4-butylenebis (N-vinylacetamide) as the crosslinking agent. A resin was obtained. These are summarized in Table 6.

[0150]

[Table 9]

Example 56 150 g of N-vinylacetamide (1.76 mol
l) and 50 g (0.53 mol) of sodium acrylate, 1.0 g of N, N'-1,4-butylenebis (N-vinylacetamide) as a crosslinking agent and 2,2 'as a polymerization initiator
-The reaction was carried out in exactly the same manner as in Example 26 except that the amount was changed to 0.29 g of azobis (2-amidinopropane) dihydrochloride to obtain a resin. The average degree of polymerization of this resin was 21,000, and the crosslink density was 1 / 16,000.

Examples 57 to 63 The reaction was carried out in exactly the same manner as in Example 56 except that various polymerization initiators were used in place of 2,2'-azobis (2-amidinopropane) dihydrochloride as the polymerization initiator. Obtained. These are summarized in Table 7.

[0153]

[Table 10]

Example 64 Reaction was carried out in exactly the same manner as in Example 50, except that N, N'-1,4-butylenebis (N-vinylacetamide) was reduced to 24 mg as a crosslinking agent and 5 mg of N, N'-methylenebisacrylamide was added. And a resin was obtained. The average degree of polymerization of this resin is 20,0
00, the crosslink density was 1 / 16,000.

Example 65 98 g (1.15 mol) of N-vinylacetamide as a monomer
And 107 g (1.14 mol) of sodium acrylate, N, N'-1,4-butylenebisacrylamide as a crosslinking agent
Except for using 11 mg, the reaction was carried out in exactly the same manner as in Example 56 to obtain a resin. The average degree of polymerization of this resin is 21,000 and the crosslink density is 1/1
It was 6,000.

Example 66 A glass reactor was charged with 250 g of water, 98 g (1.15 mol) of N-vinylacetamide, and 107 g (1.14 mol) of sodium acrylate.
mol), 11 mg of N, N'-methylenebisacrylamide and 15 mg of N, N'-1,4-butylenebisacrylamide as cross-linking agents were added and dissolved.
And 20 g of sorbitan monopalmitate, and dissolved oxygen was previously removed with nitrogen gas under a vigorous stirring in a thermostat at 30 ° C., and then 2,2′-azobis (2
A liquid obtained by dissolving 0.4 g of (amidinopropane) dihydrochloride in 49.6 g of water was added, and the mixture was reacted for 16 hours under nitrogen flow. Take out the particulate reaction product dispersed in the solvent and filter it out. 1
Dried at 05 ° C for 5 hours. The dried product was classified to obtain a product of 48 to 100 mesh. The average degree of polymerization of this resin was 21,000, and the crosslink density was 1 / 16,000.

Example 67 A resin was obtained in exactly the same manner as in Example 66 except that the same amount of sorbitan monostearate was used as the surfactant. The average degree of polymerization of this resin was 21,000, and the crosslink density was 1 / 16,000.

Example 68 A resin was obtained in exactly the same manner as in Example 66 except that 250 g of N-vinylacetamide alone was used as the monomer. The average degree of polymerization of this resin was 20,000, and the crosslink density was 1 / 16,000.

Example 69 A resin was obtained in the same manner as in Example 68 except that the same amount of sorbitan monostearate was used instead of sorbitan monopalmitate as the surfactant component. The average degree of polymerization of this resin was 20,000, and the crosslink density was 1 / 16,000.

Comparative Example 5 Resin X was obtained in the same manner as in Example 22 except that 7 g of a crosslinking agent, N, N'-1,4-butylenebis (N-vinylacetamide), was used. The average degree of polymerization of this resin is 18,000,
The crosslink density was 1/75.

Comparative Example 6 Resin Y was obtained in the same manner as in Example 22, except that 0.5 mg of N, N'-1,4-butylenebis (N-vinylacetamide) as a crosslinking agent was used. The average degree of polymerization of this resin is 19,00
0, crosslink density was 1 / 1,050,000.

Comparative Example 7 50 g (0.59 mol) of N-vinylacetamide as a monomer
The reaction was carried out in exactly the same manner as in Example 22, except that 150 g (1.60 mol) of sodium acrylate was used, to obtain a resin Z. The average degree of polymerization of this resin was 21,000, and the crosslink density was 1 / 15,000.

The monomers, crosslinking agents and initiators in Tables 5, 6 and 7 are as follows. Monomers B ₁ : sodium methacrylate, B ₂ : methyl acrylate, B ₃ : ethyl acrylate, B ₄ : butyl acrylate, B ₅ : butyl methacrylate, B ₆ : hydroxyethyl acrylate, B ₇ : hydroxyethyl methacrylate, B ₈ : Hydroxypropyl acrylate,
B ₉ : hydroxypropyl methacrylate, B ₁₀ : acrylamide, B ₁₁ : dimethylaminoethyl methacrylate, B ₁₂ : dimethylaminoethyl methacrylate methyl chloride quaternary salt, B ₁₃ : sodium 2-acrylamido-2-methylpropanesulfonate, B ₁₄ : Acrylonitrile, B ₁₅ : methyl vinyl ketone, B ₁₆ : ethyl vinyl ketone, B ₁₇ : vinyl acetate, B ₁₈ : methyl vinyl ether, B ₁₉ : ethyl vinyl ether, B ₂₀ : sodium allyl sulfonate, B ₂₁ : N-vinyl- 2-pyrrolidone, B _22: maleic acid sodium, B _23: sodium itaconate

Crosslinking agents C ₁ : ethylene glycol diacrylate, C ₂ : ethylene glycol dimethacrylate, C ₃ : diethylene glycol diacrylate, C ₄ : diethylene glycol dimethacrylate, C ₅ : divinylbenzene

Initiator D ₁ : potassium persulfate, D ₂ : ammonium persulfate, D
_3: sodium persulfate, D _4: hydrogen peroxide, D _5: ammonium persulfate / triethanolamine, D _6: ammonium persulfate / sodium sulfite, D _7: ammonium persulfate / sodium thiosulfate

(Performance test) Test example 1 (absorption of aqueous solution) 500 mg of absorbent resin was gradually added to 200 ml of the liquid to be absorbed with stirring, and after the resin was sufficiently dispersed in the liquid, the stirring was stopped and the mixture was allowed to stand for 2 hours. After the placement, the resin that had absorbed and swollen and gelled was filtered using a 200-mesh sieve, and the weight of the resin (gel) on the sieve was measured. Absorption capacity = (weight of gelled resin−weight of resin) / weight of resin

Kinds of liquid to be absorbed A: saline solution (0.9% physiological saline) B: mixed aqueous solution of inorganic salt and organic substance (human urine equivalent liquid) NaCl
_{79%, K 2 SO 4 0.20} %, MgSO 4 0.11%, CaCl 2 · 2H 2 O 0.0
8%, Urea 1.94% Ca: aqueous solution of calcium chloride (10%) b: ： (saturated aqueous solution) c: aqueous solution of calcium hydroxide (saturated aqueous solution) The results are summarized in Tables 8 to 11.

[0168]

[Table 11]

[0169]

[Table 12]

[0170]

[Table 13]

[0171]

[Table 14]

Test Example 2 (Absorption of Organic Solvent) 100 mg of an absorptive resin was added to 50 ml of a liquid to be absorbed, and the resin was absorbed at room temperature with occasional stirring to observe swelling and gelation. Those with good liquid absorbing properties gelled in 30 minutes to several hours, while those without liquid absorbing properties remained almost white powder after one week. Judgment of absorption performance was made for gelation within one day.
Those that did not gel after a week were evaluated as x,
_The results are shown in Tables 12 and 13 (single solvent) and Table 14 (mixed solvent) together with the _T values. In addition, there was substantially no gelation in one day or more to several days. The abbreviations in Tables 15 to 17 are as follows.

HFIP: 1,1,1,3,3,3-hexafluoro-2-propanol THF: tetrahydrofuran DMSO: dimethylsulfoxide NMP: N-methylpyrrolidinone DMF: N, N-dimethylformamide DMAc: N, N-dimethylacetamide

[0174]

[Table 15]

[0175]

[Table 16]

[0176]

[Table 17]

Use Example 1 The water in the water-absorbing gel of the resin of the present invention can be reused by plants, and the water is gradually released. It can absorb and release (supply water) water containing inorganic and organic ionic components, so that it can be used for fertilization, soil improvement, artificial culture, etc., and especially in afforestation and land development in mountains where water is inconvenient. It is convenient for transplanting of seedlings, turf, etc. in the prevention of dust and revegetation, etc., or water retention / supply in deserts, etc. Incidentally, the so-called water-absorbent resin that has been conventionally commercially available has an extremely low water absorption rate containing water containing an ionic component, and also has poor utilization of water in the gel even if it is gelled with water that does not contain ions in advance. The use as described above is difficult because phytotoxicity may occur. Hereinafter, a representative example will be shown and specifically described.

Test resin: A) Crosslinked product of poly N-vinylacetamide (average degree of main chain polymerization: about 20,000, crosslinking agent: N, N'-1,4-butylenebis (N-vinylacetamide), crosslinking density: about 1/1
6,000) B) Poly N-vinylacetamide / sodium acrylate
Crosslinked product (monomer molar ratio; 50:50, main chain average polymerization degree;
About 20,000, crosslinking agent; N, N'-1,4-butylenebis (N-vinylacetamide) and N, N'-methylenebisacrylamide, crosslinking density: about 1 / 17,000) C) sodium polyacrylate-crosslinked product ( Main chain average polymerization degree: about 60,000, crosslinking agent: N, N'-methylenebisacrylamide, crosslinking density: about 1 / 10,000) D) Agar

Influence on growth 1) To a group of petri dishes (diameter 10 cm), 1% by weight of a test resin or agar was added to each of distilled water and uniformly mixed, and then edible shrimp and Lettuce seeds were placed on the floor and allowed to stand in a greenhouse, and their effects on germination, rooting and growth were investigated. Germination, rooting and growth were not significantly different from the agar gel used for comparison in the gel of the test resin A), and the germination was slightly delayed in the gel of the test resin B). There was no particular problem on growth. On the other hand, in the gel of the test resin C), rooting and germination were significantly inhibited, and the growth was very poor.

2) To a group of pots (diameter 15 cm), 1% by weight of each of the test resins was added, and a certain amount of uniformly mixed sand was filled, and seeds of wheat were sown, and the seeds were allowed to stand in a greenhouse and watered daily. 5 weeks after sowing by thinning out, the standard seedlings
When the water reached about 10 cm, the last water supply was performed and the water supply was left as it was to investigate the withering status of the seedlings. In the pot mixed with the test resin A), wilting began on the 9th day after water cut off, and in the pot mixed with the test resin B), wilting started on the 7th day after water cut off.
On the other hand, in the pot mixed with the test resin C), wilting started on the fourth day after the water was cut off, and with the resin-free sand started on the third day after the water cut off.

3) To a group of pots (diameter 15 cm), 1% by weight of each of the test resins was added and mixed uniformly (volcanic ash soil /
Fill a fixed amount of sand 1: 1 mixed soil)
(Plant length: 15 to 20 cm), transplanted, irrigated once after transplantation, and then allowed to stand for 10 days without water to investigate the status of seedling survival. In the pot mixed with the test resin A), all the transplanted seedlings survived, and in the pot mixed with the test resin B), most of the pots survived. Was. In the pot mixed with the test resin C), nearly 2/3 were dead or almost dead, and the remaining seedlings were also withered.

4) The test resin was added to a group of pots (diameter 15 cm) in an amount of 1% by weight, and the mixture was mixed uniformly (volcanic ash soil /
A fixed amount of sand (1: 1 mixed soil) was filled, a fertilizer solution having the following composition was irrigated, and then seedlings of tomato (two true leaves, plant height: 10 to 15 cm) were transplanted to investigate the effect on survival and growth. _{NH 4 NO 3 58ppm, NaNO 3} 74ppm, MnSO 4 · 7H 2 O 2ppm,
Fe / EDTA 18ppm, KNO ₃ 58ppm, KH ₂ PO ₄ 38ppm, CaCl ₂
· 2H ₂ O 52 ppm, significance difference to the situation of survival and growth pot resin without additives in pots mixed with test resin A) was not observed, transplant seedlings all showed a strong growth conditions, test resin Most of the pots mixed with B) also survived and showed a vigorous growth state. On the other hand, most of the pots mixed with the test resin C) were dead or nearly dead after 2 weeks.

Use Example 2 When an aqueous solution or suspension containing a reaction component (metal ion, oxide, etc.) is brought into contact with the resin of the present invention, a gel containing the aqueous solution is formed, which is dried and then heated and calcined. As a result, the resin component is decomposed and vaporized, and the component (metal oxide) incorporated in the matrix of the crosslinked polymer is obtained as fine particles of about several nm. If the heating and sintering are performed in a non-oxidizing atmosphere, fine particles of a mixture or a reaction product with carbon in the resin component can be obtained. In addition, even for a component which evaporates by heating, such as aluminum chloride, its aqueous solution is once gelled, then reacted with ammonium hydroxide to be converted into aluminum hydroxide in the gel, and then heated and calcined. Furthermore, some alumina sols and silica sols are suspended in water as fine particles of about several nm, but can be taken into a polymer matrix as a water-absorbing gel like dissolved components such as metal ions. On the other hand, in order to obtain a ceramic article other than powder, a water-absorbing gel may be formed and then heated and fired.
In this case, it is necessary to cause strong coagulation, contrary to the case of obtaining fine powder particles. Therefore, it is necessary to increase the temperature during heating and firing and lengthen the time depending on the case. In any case, it can be realized by using the resin of the present invention having the ability to absorb an aqueous solution or a colloid solution containing ions as they are and to gel. Hereinafter, a typical example will be specifically described.

Test resin: crosslinked product of poly N-vinylacetamide (average polymerization degree of main chain: about 20,000, crosslinking agent: N, N'-1,4-butylenebis (N-vinylacetamide), crosslink density: about 1 / 16,000)

1) Al (NO_Three)_Three・ 9H_TwoDissolve 10 g of O in 25 ml of water
Then, add 1 g of the test resin, mix evenly,
After gelling, dry thoroughly and place in alumina crucible
The temperature rises to 1000 ° C in about 6 hours in a gon stream,
During this time, the mixture was heated to 1000 ° C. and fired. Remove contents after cooling
, Specific surface area sA (BET method), α conversion (X-ray diffraction
Method), median particle diameter d₅₀(Centrifugal sedimentation method) was measured
However, sA: 20 (5) m ^Two / G, α conversion: 95 (90)
%, D₅₀: 0.2 (1) μ, almost no condensation due to heating
I was not able to admit. In addition, the value of () does not use resin
It is a measured value when it is measured. In addition to the above, d₅₀: 0.05μ
A similar test was conducted by adding 10 mg of α-alumina fine particles.
Roller, sA: 18 (3) m^Two / G, α conversion: 100 (95)
%, D₅₀: 0.2 (1) μ. What is the value in parentheses?
These are measured values when no resin is used.

[0186] 2) The AlCl ₃ · 6H ₂ O 13g was dissolved in water 25 ml, which in the whole was uniformly mixed with the test resin 1g and gel, it was further added 28% aqueous ammonia solution 20 ml. The gel which was initially transparent due to the addition of the aqueous ammonia solution became cloudy. After drying, the gel was placed in an alumina crucible and heated to 1000 ° C. in an argon stream for about 6 hours.
It was heated and baked for hours. The physical properties of the obtained powder were sA: 95 m ^2.
/ G, pre-gelatinization rate: 41%, but when reheated at 105 ° C. for 5 hours, sA: 20 m ² / g, pre-gelatinization rate: 99% or more, d
₅₀ : A powder of 0.1 μ was obtained.

3) Boehmite 1.6 g, α-alumina (d
₅₀ : 0.05μ) 20 mg and 0.1 g of 68% nitric acid were added to 18 ml of water to prepare an alumina sol, and 1 g of the resin was added and uniformly mixed to form a gel, which was dried and then placed in an alumina crucible. The temperature was raised to 1000 ° C. in about 6 hours in an argon stream, and the mixture was heated and calcined for 6 hours. The physical properties of the obtained powder are s
A: 39 m ² / g, α conversion: 92%, d ₅₀ : 0.08 μ.

4) 1 g of resin in 7.1 g of 20% SiO ₂ colloid solution
, And uniformly mixed to form a gel. After drying, the gel was placed in a silicon carbide crucible, heated to 1500 ° C in about 7 hours in an argon stream, and further heated to 150 ° C for about 1 hour. Fired. Physical properties of the obtained powder were sA: 5 m ² / g, stationary phase in X-ray diffraction method: β-Si single phase, and d ₅₀ : 0.5μ.

5) The gel prepared in the same manner as in 3) above was sufficiently kneaded and extruded with a syringe through a needle of about 700 μm to form a thread. After drying, the gel was dried in a muffle furnace in air for about 1 minute.
The mixture was heated to 00 ° C. and fired to obtain a 200 μm-thick filamentary alumina.

Use Example 3 In general, the strength of a concrete or mortar product depends on the water-cement ratio of the cement composition. That is, it is known that the strength after casting and hardening increases when the amount of water is reduced as much as possible. However, at actual sites, reducing the amount of water lowers the fluidity of the cement composition, that is, lowers the workability, so there is naturally a lower limit to the water-cement ratio. In order to solve this, a water reducing agent has been used, and although a certain strength can be obtained, it has not yet been satisfied. Excess water of the concrete and mortar composition emerges on the concrete and mortar after casting as breathing water. For this reason, the water-cement ratio of the concrete and the mortar upper part becomes large, and the strength decreases toward the upper part. Also, since the breathing water does not proceed to the next step unless it disappears, the construction period is lengthened.
Therefore, a method has been proposed in which excess water is removed using an absorbent, and the gel that has absorbed water gradually releases water inside the concrete to perform internal wet curing, but currently commercially available water absorbents have an ionic component, particularly calcium. Since it hardly absorbs an aqueous solution containing polyvalent ion components such as ions, a sufficient effect cannot be exhibited. However, as apparent from the absorption performance table, the resin of the present invention absorbs even a saturated aqueous solution of calcium hydroxide, which is a main component of cement, and can be used as described above.

Further, the cement composition containing the resin of the present invention hardly causes rapid dryout at the time of hardening, prevents the generation of cracks by the effect of wet curing, increases the strength, and reduces the dimensional change rate. improves. In addition to the method of mixing with the concrete and mortar composition, there is also a method of preparing an absorbent sheet using the resin of the present invention and covering the concrete and mortar after casting. In this method, the strength is increased by the wet curing effect because the absorbent sheet absorbs the breathing water and is in close contact with the casting surface.

By curing the mortar composition containing the resin of the present invention, the gelled portions remain as voids, and as a result, the density of the mortar can be reduced (the weight of the mortar can be reduced). Incidentally, currently available water-absorbing agents hardly absorb an aqueous solution containing a polyvalent ion component, and therefore have few voids in the mortar and are difficult to use as described above. In any case, the effect is exhibited by using the resin of the present invention having an ability to absorb a saturated calcium hydroxide aqueous solution.

1) A test resin was prepared for a concrete composition containing 300 kg of ordinary Portland cement (manufactured by Nippon Cement), 225 kg of tap water, 670.6 kg of fine aggregate and 1031.1 kg of coarse aggregate.
(A), (B) and (C) were mixed together in an amount of 600 g. Except that the kneading time is 4 minutes, it is manufactured according to JISA 1138 “How to make concrete in a test room”, the breathing amount and breathing rate are measured according to JIS A 1123, and the compressive strength is measured according to JIS A 1108. Measured. Table 15 shows the results.

Test resin: A) Crosslinked product of poly N-vinylacetamide (average degree of polymerization of main chain: about 20,000, crosslinking agent: N, N'-1,4-butylenebis (N-vinylacetamide), crosslinking density: about 1/1
6,000) B) Cross-linked poly N-vinylacetamide / sodium acrylate (monomer molar ratio: 50/50, main chain average polymerization degree: about
20,000, crosslinking agent; N, N'-1,4-butylenebis (N
-Vinylacetamide) and N, N'-methylenebisacrylamide, crosslink density: about 1 / 17,000) C) The results when no commercially available water-absorbent resin "Sumikagel S-50" was added are also shown in Table 15 as comparative examples. did.

[0195]

[Table 18]

By incorporating the resin of the present invention, the breathing was clearly reduced and the compressive strength was improved.

2) 6.0 g of each of the test resins (A), (B) and (C) was mixed with a mortar composition containing 3000 g of ordinary Portland cement (manufactured by Nippon Cement), 1500 g of tap water and 6000 g of fine aggregate. Knead, length change rate is JIS A 1129
It measured based on. Table 16 shows the results.

Test resin: A) Crosslinked product of poly N-vinylacetamide (average degree of polymerization of main chain: about 20,000, crosslinking agent: N, N'-1,4-butylenebis (N-vinylacetamide), crosslink density: about 1/1
6,000) B) Cross-linked poly N-vinylacetamide / sodium acrylate (monomer molar ratio: 50/50, main chain average polymerization degree: about
20,000, crosslinking agent; N, N'-1,4-butylenebis (N
-Vinylacetamide), crosslink density: about 1 / 17,000) C) The results when no commercially available water-absorbent resin "Sumikagel S-50" resin was added are also shown in Table 16 as comparative examples.

[0199]

[Table 19]

By incorporating the resin of the present invention, the rate of change in length was clearly reduced.

3) Each of the test resins (A), (B) and (C) is uniformly spread at 26.5 g / m ² on the nonwoven fabric, and the nonwoven fabric is put on the sprayed resin. This absorbent sheet is placed on the concrete after casting to produce a test specimen. The mix of this concrete is ordinary Portland cement (Nippon Cement) 3
00 kg / m ³ , tap water 225 kg / m ³ , fine aggregate 670.6 kg / m
³ and 1031.1 kg / m ³ of coarse aggregate, and were prepared according to JIS A 1138. The specimen was removed from the mold on 7 days of age and the absorbent sheet was left as it was, and the compressive strength of 28 days and 91 days of age was JIS A 11
It was measured according to 08. Table 17 shows the results.

Test resin: A) Crosslinked product of poly N-vinylacetamide (average degree of main chain polymerization: about 20,000, crosslinking agent: N, N'-1,4-butylenebis (N-vinylacetamide), crosslinking density: about 1/1
6,000) B) Cross-linked poly N-vinylacetamide / sodium acrylate (monomer molar ratio: 50/50, main chain average polymerization degree: about
20,000, crosslinking agent; N, N'-1,4-butylenebis (N
-Vinylacetamide) and N, N'-methylenebisacrylamide, crosslinking density; about 1 / 17,000) C) Commercially available water-absorbent resin "Sumikagel S-50" The results when no resin is added are also shown in Table 17 as comparative examples. did.

[0203]

[Table 20]

The absorbent sheet made by using the resin of the present invention clearly has improved compressive strength.

4) A mortar composition containing 3000 g of ordinary Portland cement (manufactured by Nippon Cement), 1500 g of tap water and 6000 g of fine aggregate was kneaded with 12 g of each of the test resins (A), (B) and (C). Then, the density on the 7th day was measured. Table 18 shows the results.

Test resin: A) Crosslinked poly N-vinylacetamide (average degree of polymerization of main chain; about 20,000, crosslinking agent: N, N'-1,4-butylenebis (N-vinylacetamide), crosslinking density: about 1/1
6,000) B) Cross-linked poly N-vinylacetamide / sodium acrylate (monomer molar ratio: 50/50, main chain average polymerization degree: about
20,000, crosslinking agent; N, N'-1,4-butylenebis (N
-Vinylacetamide) and N, N'-methylenebisacrylamide, crosslink density: about 1 / 17,000) C) Commercially available water-absorbing resin "Sumikagel S-50" The results when no resin is added are also shown in Table 18 as comparative examples. did.

[0207]

[Table 21]

By mixing the absorbent of the present invention, the weight of the mortar was clearly reduced.

Use Example 4 The resin of the present invention does not show a significant decrease in the absorption rate even in an aqueous solution containing a large amount of calcium ions. Therefore, the desiccant containing the resin of the present invention absorbs a large amount of calcium chloride deliquescent resulting from moisture absorption, and the entire desiccant becomes non-fluidized due to gelling of the resin. As a result, there is no contamination of other substances. Incidentally, a so-called water-absorbing resin which has been conventionally commercially available is not suitable for the above-mentioned applications because the water absorption of an aqueous solution containing polyvalent ions such as calcium ions is extremely reduced. A typical example is shown below.

5 g, 10 g, and 50 g of the resin (A) of the present invention were added to 100 g of the pulverized product of calcium chloride (a product passed through 200 MESH), and the resulting mixture was mechanically mixed with each other to absorb moisture absorbents 1, 2, and 3.
I got Calcium chloride crushed product (200MESH passed product) 1
10 g of the resin (B) of the present invention was added to 00 g and mechanically mixed to obtain a hygroscopic agent 4. Ground calcium chloride (200MESH
50 g of the resin (C) was added to 100 g of the passed product, and the mixture was mechanically mixed to obtain a hygroscopic agent 5. Ground calcium chloride (200MES
H-passed product) was used alone as the moisture absorbent 6.

Each of 50 g of the hygroscopic agent obtained by the above preparation was left in a thermo-hygrostat (temperature: 30 ° C., humidity: 95%). Table 19 shows the results.

Test resin: A) Crosslinked product of poly N-vinylacetamide (average degree of polymerization of main chain: about 20,000, crosslinking agent: N, N'-1,4-butylenebis (N-vinylacetamide), crosslinking density: about 1/1
6,000) B) Cross-linked poly N-vinylacetamide / sodium acrylate (monomer molar ratio: 50/50, main chain average polymerization degree: about
20,000, crosslinking agent; N, N'-1,4-butylenebis (N
-Vinylacetamide) and N, N'-methylenebisacrylamide, crosslinking density: about 1 / 17,000) C) Commercially available water-absorbent resin "Diawet S-II"

[0213]

[Table 22]

By adding the resin of the present invention, the fluidity of the hygroscopic agent was obviously lost.

Use Example 5 The resin of the present invention can be used for sanitary articles such as disposable diapers and napkins since the water absorption rate hardly decreases even for body fluids (urine and menses) containing a large amount of salts. Conventionally commercially available so-called water-absorbent resin, the disposable diaper containing the resin of the present invention has a large urine water absorption capacity, as a result, the amount of resin required to absorb the same amount of urine can be reduced, It can be said that the bodily fluid absorbent is more suitable for the above uses. The basic form of sanitary goods is 1. 1. liquid permeable surface sheet; Absorbing layer (polymer absorber,
2. cotton-like pulp, etc.); It is a breathable waterproof sheet. Among them, the resin of the present invention is used for the absorption layer. There are many shapes of the absorbing layer, but typical ones are those in which a resin is sprayed on a nonwoven fabric, and those in which a resin is sandwiched between nonwoven fabrics. Absorption capacity was measured in a form close to these. The method for measuring the water absorption capacity is shown below.

0.4 g of each of the test resins (A), (B), (C) and (D) was evenly spread on a 165 × 60 mm tissue paper, and one more tissue paper was placed thereon. ,
Spray water with light pressure (spray amount is appropriate). Press down with an embossing roller heated to about 140 ° C. 80 ° C due to insufficient drying of the emboss roller alone
For 2 hours under vacuum. This sheet is placed on a wire mesh and immersed in artificial urine at a liquid temperature of 30 ° C. After 1 hour, the sheet is taken out together with the wire net, tilted at 45 °, drained for 1 minute, and weighed. Table 20 shows the results.

Test resin: A) Crosslinked product of poly N-vinylacetamide (average degree of polymerization of main chain; about 20,000, crosslinking agent: N, N'-1,4-butylenebis (N-vinylacetamide), crosslinking density: about 1/1
6,000) B) Cross-linked poly N-vinylacetamide / sodium acrylate (monomer molar ratio: 50/50, main chain average polymerization degree: about
20,000, crosslinking agent; N, N'-1,4-butylenebis (N
-Vinylacetamide) and N, N'-methylenebisacrylamide, crosslinking density: about 1 / 17,000) C) Commercially available water-absorbent resin "Sumikagel S-50" D) Commercially available water-absorbent resin "Diawet S-II"

[0218]

[Table 23]

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C07C 233/18 C07C 233/18 C08F 226/02 C08F 226/02 C09K 3/00 103 C09K 3/00 103L 17/18 17/18 H (72) Inventor Kuniomi Marumo 2 Oaza-shi, Oita-shi, Oita Prefecture Showa Denko K.K.In Oita Research Laboratory (72) Inventor Kiichi Hosoda 5-1 Ogimachi, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Showa Denko KK (56) References JP-A-3-227310 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) CA (STN) REGISTRY (STN)

Claims (14)

(57) [Claims] [Claim 1] Formula [1]: [Wherein, R ¹ represents a hydrogen atom or a methyl group, R ² represents an alkylene group having 3 to 10 carbon atoms; a group — (CH ₂ .CHR ³ .O) _n −
CH ₂ · CHR ³ — (wherein, R ³ represents a hydrogen atom or a methyl group, and n represents an integer of 1 to 4); (Where m represents 0 or 4)]
-Vinyl carboxylic acid amide) compounds. 2. A molar ratio of (i) a monomer repeating unit represented by the formula [2] or [3] to (ii) a crosslinking agent repeating unit represented by the formula [1 ′] [(i) / ( ii)] 30/70 ~
A crosslinked polymer comprising a ratio of 99.9999 / 0.0001. Embedded image Embedded image Embedded image [Wherein, R ¹ , R ⁴ , R ⁵ and R ⁶ each independently represent hydrogen or a methyl group, and R ² represents an alkylene group having 3 to 10 carbon atoms; a group — (CH ₂ .CHR ³ .O) _n -CH ₂ · CHR ^3- (wherein, R
³ represents a hydrogen atom or a methyl group, and n represents an integer of 1 to 4); (Where m represents 0 or 4), and A represents a 2-ketopyrrolidinyl group. ] 3. A monomer represented by the formula [2 '] or N-
3. The method for producing a crosslinked polymer according to claim 2, wherein vinyl-2-pyrrolidone and a bis (N-vinylcarboxylic acid amide) compound of the formula [1] are copolymerized. Embedded image Embedded image (In the formula, R ¹ , R ² , R ³ and R ⁴ are as defined above.) 4. A molar ratio of (i) (a) a monomer repeating unit represented by the formula [2] to (b) a monomer repeating unit represented by the formula [4] and / or [5]. [(A) / (b)] is 30 /
The monomer repeating unit containing 70-99 / 1 at a ratio of (ii) the crosslinking unit repeating unit represented by the formula [1 '] in a molar ratio [(i) / (ii)] of 30 / 70-99.9999 / A crosslinked polymer comprising 0.0001. Embedded image [Formula 10] [Formula 11] Embedded image [Wherein R ¹ , R ² , R ⁴ and R ⁵ are as defined above, R ⁷ represents a hydrogen atom or a methyl group, and A ′ represents a group-
COOX (where X is a hydrogen atom, an alkali metal, and has 1 to 1 carbon atoms)
6 represents an alkyl group or a hydroxyl group, a dialkylamino group or a lower alkyl group substituted with a quaternary ammonium group); a group -CONHY (where Y is a hydrogen atom or a dialkylamino group, a quaternary ammonium group, a sulfone) A lower alkyl group substituted with an acid or an alkali metal salt thereof); a cyano group; a 2-ketopyrrolidinyl group; a lower alkoxy group; a lower acyl group; a lower acyloxy group or a lower alkyl substituted with a sulfonic acid or an alkali metal salt thereof. M represents a hydrogen atom, an ammonium group or an alkali metal, and p represents 0 or 1. When R ⁷ is a methyl group, A ′ represents a cyano group, 2-ketopyrrolidinyl group; a lower alkoxy group; a lower acyl group. Not a lower acyloxy group or a lower alkyl group substituted with sulfonic acid or a salt thereof. ] 5. (i) (a) a monomer represented by the formula [2 '] and (b) a monomer represented by the formula [4'] and / or [5 '], CH ₂ = CR ⁷ A '[4'] MOOCCH = CH (CH ₂ ) _p COOM [5 '] (wherein R ⁷ , A', M and p are as defined above) (ii) bis of formula [1] 5. The method for producing a crosslinked copolymer according to claim 4, wherein the copolymer is copolymerized with an (N-vinylcarboxylic acid amide) compound. Embedded image Embedded image (In the formula, R ¹ , R ² , R ⁴ and R ⁵ are as defined above.) 6. A liquid absorbent for water or an organic solvent, comprising the crosslinked polymer according to claim 2 or 4 as a main component. 7. The liquid absorbent according to claim 6, wherein the average degree of polymerization of the main chain is in the range of 100 to 500,000, and the crosslinking density of the crosslinking agent is in the range of 1/100 to 1 / 500,000. 8. The liquid absorbent according to claim 6, wherein the crosslinking agent is at least one of the following compounds: N, N'-1,4.
-Butylenebis (N-vinylacetamide), N, N '
-1,6-hexylenebis (N-vinylacetamide), N, N'-1,10-decylenebis (N-vinylacetamide), N, N'-3-oxa-1,5-pentylenebis (N-vinylacetamide) , N, N'-3,
6-dioxa-1,8-octylenebis (N-vinylacetamide), N, N'-p-xylylenebis (N-vinylacetamide), N, N'-diacetyl-N, N '
-Divinyl-1,4-bisaminomethylcyclohexane. 9. The liquid absorbent according to claim 6, wherein the cross-linking agent is a complex of at least one of the following compound (A) and at least one of the following compound (B): (A) N, N′-methylene Bisacrylamide, N, N'-1,4-butylenebis (N-vinylacetamide), N, N'-1,6-
Hexylene bis (N-vinylacetamide), N, N '
-1,10-decylenebis (N-vinylacetamide),
N, N'-3-oxapentylenebis (N-vinylacetamide), N, N'-3,6-dioxa-1,8-octylenebis (N-vinylacetamide), N, N'-
p-xylylenebis (N-vinylacetamide), N,
N'-diacetyl-N, N'-divinyl-1,4-bisaminomethylcyclohexane; (B) N, N'-methylenebisacrylamide, ethylene glycol di (meth)
Acrylate, diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, divinylbenzene, divinyl ether. 10. The organic solvent is a solvent polarity parameter E _T value.
The liquid absorbent according to claim 6, which is a single liquid of 45 or more or a mixed liquid of _ET value of 43 or more. 11. The liquid absorbent according to claim 6, wherein the liquid absorbent is used for planting material or as an agent for retaining (supplying) an artificial medium. 12. The liquid absorbent according to claim 6, which is used as a body fluid absorbent for hygiene articles. 13. The liquid absorbent according to claim 6, which is an absorbent containing calcium, such as a concrete curing agent, a cement modifier, and a moisture absorbent. 14. The liquid absorbent according to claim 6, which is used as a dispersant for a metal salt solution (complex forming agent with a metal compound).