JP6864479B2 - Cement admixture and cement composition - Google Patents

Description

The present invention relates to cement admixtures and cement compositions.

Cement compositions such as mortar and concrete generally contain cement, aggregate and water, preferably further with a cement admixture to increase fluidity and reduce water.

Recently, there have been increasing demands for cement compositions to improve the strength performance of cured products in addition to the improvement of water reduction performance. For example, depending on the use of the cement composition, early development of strength is desired, and various studies have been conducted (for example, Patent Document 1).

On the other hand, depending on the use of the cement composition, it is required to improve the strength of the cured product of the cement composition over a long period of time (for example, to improve the strength at the level of 4 weeks).

Japanese Unexamined Patent Publication No. 2011-84459

An object of the present invention is to provide a cement admixture capable of significantly improving the strength of a cured product of a cement composition over a long period of time. Another object of the present invention is to provide a cement composition in which the strength of a cured product can be remarkably improved over a long period of time.

The cement admixture of the present invention
A cement admixture containing a polyoxyalkylene compound (A), an alkanolamine compound (B), and a dispersant (C).
The polyoxyalkylene compound (A)
(I) General formula (1): YO (A ¹ O) _{Unsaturated polyalkylene glycol ether-based monomer represented by m} R ⁰ (a) (In the general formula (1), Y has 2 carbon atoms. Represents an alkenyl group of ~ 8, R ⁰ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, A ¹ O represents an oxyalkylene group having 2 to 18 carbon atoms, and m represents A. ^{It represents the average number of moles of the oxyalkylene group represented by 1} O, and m is 2 to 300) -derived structural unit (I) and unsaturated amide-based monomer (b) -derived structural unit (II). ) And / or a copolymer (A1) having a structural unit (III) derived from the hydroxyalkyl ester (c) of the unsaturated carboxylic acid.
(Ii) Polymer (A2) having a structural unit derived from an alkylene oxide adduct of unsaturated carboxylic acid,
(Iii) An alkylene oxide adduct (A3) of a trihydric or higher polyhydric alcohol,
(Iv) Polyalkylene glycol (A4),
At least one selected from
The dispersant (C)
(V) General formula (1): YO (A ¹ O) _{Unsaturated polyalkylene glycol ether-based monomer represented by m} R ⁰ (a) (In the general formula (1), Y has 2 carbon atoms. Represents an alkenyl group of ~ 8, R ⁰ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, A ¹ O represents an oxyalkylene group having 2 to 18 carbon atoms, and m represents A. ^{It represents the average number of moles of the oxyalkylene group represented by 1} O, and m is 2 to 300) -derived structural unit (I) and unsaturated carboxylic acid-based monomer (d) -derived structural unit (d). Polycarboxylic acid-based dispersant (C1), which is a polycarboxylic acid-based copolymer having IV),
(Vi) Sulfonic acid-based dispersant (C2),
(Vii) Phosphoric acid-based dispersant (C3),
At least one selected from.

The cement composition of the present invention
A cement composition containing a polyoxyalkylene compound (A), an alkanolamine compound (B), a dispersant (C), and cement.
The polyoxyalkylene compound (A)
(I) General formula (1): YO (A ¹ O) _{Unsaturated polyalkylene glycol ether-based monomer represented by m} R ⁰ (a) (In the general formula (1), Y has 2 carbon atoms. Represents an alkenyl group of ~ 8, R ⁰ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, A ¹ O represents an oxyalkylene group having 2 to 18 carbon atoms, and m represents A. ^{It represents the average number of moles of the oxyalkylene group represented by 1} O, and m is 2 to 300) -derived structural unit (I) and unsaturated amide-based monomer (b) -derived structural unit (II). ) And / or a copolymer (A1) having a structural unit (III) derived from the hydroxyalkyl ester (c) of the unsaturated carboxylic acid.
(Ii) Polymer (A2) having a structural unit derived from an alkylene oxide adduct of unsaturated carboxylic acid,
(Iii) An alkylene oxide adduct (A3) of a trihydric or higher polyhydric alcohol,
(Iv) Polyalkylene glycol (A4),
At least one selected from
The dispersant (C)
(V) General formula (1): YO (A ¹ O) _{Unsaturated polyalkylene glycol ether-based monomer represented by m} R ⁰ (a) (In the general formula (1), Y has 2 carbon atoms. Represents an alkenyl group of ~ 8, R ⁰ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, A ¹ O represents an oxyalkylene group having 2 to 18 carbon atoms, and m represents A. ^{It represents the average number of moles of the oxyalkylene group represented by 1} O, and m is 2 to 300) -derived structural unit (I) and unsaturated carboxylic acid-based monomer (d) -derived structural unit (d). Polycarboxylic acid-based dispersant (C1), which is a polycarboxylic acid-based copolymer having IV),
(Vi) Sulfonic acid-based dispersant (C2),
(Vii) Phosphoric acid-based dispersant (C3),
At least one selected from.

According to the present invention, it is possible to provide a cement admixture capable of significantly improving the strength of a cured product of a cement composition over a long period of time. Further, it is possible to provide a cement composition in which the strength of the cured product can be remarkably improved over a long period of time.

In the present specification, the expression "(meth) acrylic" means "acrylic and / or methacrolein", and the expression "(meth) acrylate" means "acrylate and / or methacrylate". When the expression "(meth) allyl" is used, it means "allyl and / or methacrolein", and when the expression "(meth) acrolein" is used, "acrolein and / or methacrolein" is used. It means "rain". In addition, when the expression "acid (salt)" is used in the present specification, it means "acid and / or a salt thereof".

≪≪Cement admixture≫≫
The cement admixture of the present invention contains a polyoxyalkylene compound (A), an alkanolamine compound (B) and a dispersant (C).

The polyoxyalkylene compound (A) may be one kind or two or more kinds.

The alkanolamine compound (B) may be one kind or two or more kinds.

The dispersant (C) may be one kind or two or more kinds.

The cement admixture of the present invention can contribute to the improvement of the dispersibility of the cement composition by containing the polyoxyalkylene compound (A), the alkanolamine compound (B) and the dispersant (C), and the cement composition. It exerts the effect that the strength of the cured product can be remarkably improved over a long period of time.

The content ratio of the total amount of the polyoxyalkylene compound (A), the alkanolamine compound (B) and the dispersant (C) in the cement admixture of the present invention is preferably 50% by mass to 100% by mass, and more. It is preferably 70% by mass to 100% by mass, more preferably 90% by mass to 100% by mass, particularly preferably 95% by mass to 100% by mass, and most preferably substantially 100% by mass. That is, most preferably, the cement admixture of the present invention comprises only the polyoxyalkylene compound (A), the alkanolamine compound (B) and the dispersant (C). By adjusting the content ratio of the total amount of the polyoxyalkylene compound (A), the alkanolamine compound (B) and the dispersant (C) in the cement admixture of the present invention within the above range, the cement admixture of the present invention can be mixed. The agent can improve the strength of the cured product of the cement composition more significantly over the long term.

The content ratio of the polyoxyalkylene compound (A) in the cement admixture of the present invention is preferably 0.5% by mass to 80% by mass, more preferably 1% by mass to 70% by mass, and even more preferably. It is 3% by mass to 60% by mass, particularly preferably 5% by mass to 50% by mass, and most preferably 10% by mass to 40% by mass. By adjusting the content ratio of the polyoxyalkylene compound (A) in the cement admixture of the present invention within the above range, the cement admixture of the present invention makes the strength of the cured product of the cement composition more remarkable over a long period of time. Can be improved. When the content of the polyoxyalkylene compound (A) in the cement admixture of the present invention is less than 0.5% by mass, the cement admixture of the present invention improves the strength of the cured product of the cement composition over a long period of time. It may be difficult.

The content ratio of the alkanolamine compound (B) in the cement admixture of the present invention is preferably 0.2% by mass to 60% by mass, more preferably 0.5% by mass to 50% by mass, and further preferably. Is 1% by mass to 40% by mass, and particularly preferably 3% by mass to 30% by mass. By adjusting the content ratio of the alkanolamine compound (B) in the cement admixture of the present invention within the above range, the cement admixture of the present invention significantly improves the strength of the cured product of the cement composition over a long period of time. I can let you. When the content of the alkanolamine compound (B) in the cement admixture of the present invention is less than 0.2% by mass, it is difficult for the cement admixture of the present invention to improve the strength of the cured product of the cement composition over a long period of time. There is a risk.

The content ratio of the dispersant (C) in the cement admixture of the present invention is preferably 25% by mass to 99% by mass, more preferably 30% by mass to 97% by mass, and further preferably 35% by mass to 35% by mass. It is 95% by mass, particularly preferably 40% by mass to 93% by mass, and most preferably 45% by mass to 90% by mass. By adjusting the content ratio of the dispersant (C) in the cement admixture of the present invention within the above range, the cement admixture of the present invention can more significantly improve the dispersibility of the cement composition. When the content ratio of the dispersant (C) in the cement admixture of the present invention is less than 25% by mass, it may be difficult for the cement admixture of the present invention to improve the dispersibility of the cement composition.

The content ratio of the polyoxyalkylene compound (A) in the cement admixture of the present invention is preferably 0.005% by mass to 0.3% by mass, more preferably 0.01% by mass or more, based on the cement. It is 0.25% by mass, more preferably 0.02% by mass to 0.2% by mass, particularly preferably 0.02% by mass to 0.15% by mass, and most preferably 0.05% by mass. ~ 0.1% by mass. By adjusting the content ratio of the polyoxyalkylene compound (A) in the cement admixture of the present invention within the above range, the cement admixture of the present invention makes the strength of the cured product of the cement composition more remarkable over a long period of time. Can be improved. When the content ratio of the polyoxyalkylene compound (A) in the cement admixture of the present invention is less than 0.005% by mass with respect to the cement, the cement admixture of the present invention has the strength of the cured product of the cement composition. May be difficult to improve over the long term.

The content ratio of the alkanolamine compound (B) in the cement admixture of the present invention is preferably 0.002% by mass to 0.2% by mass, more preferably 0.005% by mass to 0, based on the cement. It is .15% by mass, more preferably 0.01% by mass to 0.1% by mass, particularly preferably 0.015% by mass to 0.07% by mass, and most preferably 0.02% by mass to 0.02% by mass. It is 0.05% by mass. By adjusting the content ratio of the alkanolamine compound (B) in the cement admixture of the present invention within the above range, the cement admixture of the present invention significantly improves the strength of the cured product of the cement composition over a long period of time. I can let you. When the content ratio of the alkanolamine compound (B) in the cement admixture of the present invention is less than 0.002% by mass with respect to the cement, the cement admixture of the present invention determines the strength of the cured product of the cement composition. It may be difficult to improve over a long period of time.

The content ratio of the dispersant (C) in the cement admixture of the present invention is preferably 0.01% by mass to 1% by mass, and more preferably 0.03% by mass to 0.8% by mass with respect to the cement. %, More preferably 0.05% by mass to 0.6% by mass, particularly preferably 0.1% by mass to 0.5% by mass, and most preferably 0.15% by mass to 0.4. It is mass%. By adjusting the content ratio of the dispersant (C) in the cement admixture of the present invention within the above range, the cement admixture of the present invention can more significantly improve the dispersibility of the cement composition. When the content ratio of the dispersant (C) in the cement admixture of the present invention is less than 0.01% by mass with respect to the cement, the cement admixture of the present invention is difficult to improve the dispersibility of the cement composition. There is a risk.

The ratio of the alkanolamine compound (B) to the polyoxyalkylene compound (A) in the cement admixture of the present invention is preferably 1% by mass to 10000% by mass, more preferably 5% by mass to 1000% by mass. Yes, more preferably 10% by mass to 500% by mass, further preferably 15% by mass to 300% by mass, still more preferably 20% by mass to 200% by mass, and particularly preferably 30% by mass to 150% by mass. %, Most preferably 50% by mass to 100% by mass. By adjusting the ratio of the alkanolamine compound (B) to the polyoxyalkylene compound (A) in the cement admixture of the present invention within the above range, the cement admixture of the present invention is a cured product of the cement composition. The strength can be improved more significantly over the long term.

<< Polyoxyalkylene compound (A) >>
The polyoxyalkylene compound (A) is
(I) General formula (1): YO (A ¹ O) _{Unsaturated polyalkylene glycol ether-based monomer represented by m} R ⁰ (a) (In the general formula (1), Y has 2 carbon atoms. Represents an alkenyl group of ~ 8, R ⁰ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, A ¹ O represents an oxyalkylene group having 2 to 18 carbon atoms, and m represents A. ^{It represents the average number of moles of the oxyalkylene group represented by 1} O, and m is 2 to 300) -derived structural unit (I) and unsaturated amide-based monomer (b) -derived structural unit (II). ) And / or a copolymer (A1) having a structural unit (III) derived from the hydroxyalkyl ester (c) of the unsaturated carboxylic acid.
(Ii) Polymer (A2) having a structural unit derived from an alkylene oxide adduct of unsaturated carboxylic acid,
(Iii) An alkylene oxide adduct (A3) of a trihydric or higher polyhydric alcohol,
(Iv) Polyalkylene glycol (A4),
At least one selected from.

The polyoxyalkylene compound (A) can mainly contribute to the improvement of the strength-enhancing effect of the cured product of the cement composition in the cement admixture of the present invention.

<Copolymer (A1)>
The copolymer (A1) is unsaturated with the structural unit (I) derived from the unsaturated polyalkylene glycol ether-based monomer (a) represented by the general formula (1): YO (A ¹ O) _m R ^0. It has a structural unit (II) derived from the amide-based monomer (b) and / or a structural unit (III) derived from the hydroxyalkyl ester (c) of the unsaturated carboxylic acid. When the copolymer (A1) has such a structure, the cement admixture of the present invention can improve the strength of the cured product of the cement composition more remarkably over a long period of time.

General formula (1): The structural unit (I) derived from the unsaturated polyalkylene glycol ether-based monomer (a) represented by ^{YO (A 1} O) _m R ^{0 is specifically a general formula (1).} It is a structural unit in which the unsaturated double bond (C = C) of Y in the unsaturated polyalkylene glycol ether-based monomer (a) represented by 1) becomes −C—C− by the polymerization reaction.

In the general formula (1), Y represents an alkenyl group having 2 to 8 carbon atoms.

As Y, for example, a vinyl group (CH ₂ = CH- group), a 1-methyl-1-vinyl group (CH ₂ = C (CH ₃ ) -group), a 2-propenyl group (allyl group) (CH ₂ =). CHCH ₂ -group), 2-methyl-2-propenyl group (metallic group) (CH ₂ = C (CH ₃ ) -CH _2- group), 3-methyl-3-butenyl group (isoprenyl group) (CH ₂ = C (CH ₃ ) -CH ₂ CH ₂ -group) and the like. Among these, a vinyl group, a 2-propenyl group (allyl group), a 2-methyl-2-propenyl group (metharyl group), and a 3-methyl-3-butenyl group (isoprenyl group) are preferable.

In the general formula (1), R ⁰ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms. Examples of the hydrocarbon group having 1 to 30 carbon atoms include an alkyl group having 1 to 30 carbon atoms (aliphatic alkyl group and alicyclic alkyl group), an alkenyl group having 1 to 30 carbon atoms, and a carbon atom number. Examples thereof include an alkynyl group of 1 to 30 and an aromatic group having 6 to 30 carbon atoms. A point capable of further exhibit the effect of the present invention, R ³ is preferably a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, more preferably, carbon hydrogen atom or 1 to 12 carbon atoms It is a hydrogen group, more preferably a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and particularly preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

In the general formula (1), A ¹ O represents an oxyalkylene group having 2 to 18 carbon atoms. The oxyalkylene group preferably has 2 to 8 carbon atoms, more preferably 2 to 4 carbon atoms.

Examples of A ¹ O include an oxyethylene group, an oxypropylene group, an oxybutylene group, and an oxystyrene group. Among these, an oxyethylene group, an oxypropylene group and an oxybutylene group are preferable, and an oxyethylene group and an oxypropylene group are more preferable. In the case where two or more different A ^{1 O} structure is present, these different A ^{1 O} structure, random addition, block addition, may be present in any form of alternating addition, and the like. In order to secure a balance between hydrophilicity and hydrophobicity, it is preferable that the oxyethylene group contains an oxyethylene group as an essential component. More specifically, with respect to 100 mol% of all oxyalkylene groups, 50 mol% or more is preferably an oxyethylene group, 80 mol% or more is more preferably an oxyethylene group, and 90 mol% or more is It is particularly preferably an oxyethylene group, and 100 mol% is particularly preferably an oxyethylene group.

In the general formula (1), m represents the average number of moles of oxyalkylene group represented by ^{A 1 O, and is 2 to 300.} n is preferably 5 to 150, more preferably 10 to 100, still more preferably 15 to 75, and particularly preferably 20 to 50. The "average number of moles added" means the average number of moles of oxyalkylene groups added in one mole of the compound. When m is within such a range, the cement admixture of the present invention can more significantly improve the strength of the cured product of the cement composition over a long period of time.

The unsaturated amide-based monomer (b) is preferably represented by the general formula (2).

The structural unit (II) derived from the unsaturated amide-based monomer (b) represented by the general formula (2) is specifically the unsaturated amide-based monomer represented by the general formula (2). This is a structural unit in which the unsaturated double bond (C = C) possessed by (b) becomes −C—C− by the polymerization reaction.

In general formula (2), R ¹ , R ² and R ³ represent the same or different hydrogen atom, methyl group, or − (CH ₂ ) _p COM group. p is an integer from 0 to 2. M represents a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group, an organic ammonium group, or an organic amine group.

In the general formula (2), ^{R 4} and ^{R _{5, - (CR 6 2) n}} - represents an _{(R 7)} r -R ⁸ group ^- _(A 2 O) q. R ⁶ is a hydrogen atom or an alkyl group having 1 to 18 carbon atoms. n is an integer from 0 to 5. R ⁷ represents a hydrogen atom or a methylene group. r is an integer from 0 to 5. R ⁸ represents a hydrogen atom, a phosphate (salt) group, a sulfonic acid (salt) group, a carboxylic acid (salt) group, or a hydroxyl group.

In the general formula (2), A ² O represents an oxyalkylene group having 2 to 18 carbon atoms. A point capable of further exhibit the effect of the present invention, A 2 ^O is preferably an oxyalkylene group having 2 to 8 carbon atoms, more preferably an oxyalkylene group having 2 to 4 carbon atoms. When A ² O is any two or more types selected from an oxyethylene group, an oxypropylene group, an oxybutylene group, an oxystyrene group, etc., ^{the addition form of A 2} O is random addition or block addition. , Alternate addition, etc. may be used. In order to secure a balance between hydrophilicity and hydrophobicity, it is preferable that the oxyethylene group contains an oxyethylene group as an essential component, and 50 mol% or more of the total oxyalkylene group is an oxyethylene group. Preferably, 90 mol% or more of the total oxyalkylene group is an oxyethylene group, 95 mol% or more of the total oxyalkylene group is particularly preferably an oxyethylene group, and 100 mol% of the total oxyalkylene group. Is most preferably an oxyethylene group.

In the general formula (2), q represents the average number of moles of oxyalkylene group represented by ^{A 2 O, and is 0 to 200.} In terms of further exhibiting the effects of the present invention, q is preferably 0 to 180, more preferably 0 to 160, still more preferably 0 to 140, and particularly preferably 0 to 120. Most preferably 0 to 100.

Examples of the unsaturated amide-based monomer (b) represented by the general formula (2) include (meth) acrylic (alkyl) amide, N-methylol (meth) acrylamide, and N, N-dimethyl (meth) acrylamide. And so on.

The unsaturated amide-based monomer (b) represented by the general formula (2) is preferably acrylamide in that the effects of the present invention can be further exhibited.

The unsaturated amide-based monomer (b) represented by the general formula (2) may be of only one type or of two or more types.

The structural unit (III) derived from the hydroxyalkyl ester (c) of the unsaturated carboxylic acid is specifically an unsaturated double bond (C = C) contained in the hydroxyalkyl ester (c) of the unsaturated carboxylic acid. It is a structural unit that has become -CC- by the polymerization reaction.

The hydroxyalkyl ester (c) of unsaturated carboxylic acid is preferably a hydroxyalkyl ester of (meth) acrylic acid, more preferably a hydroxyethyl ester of (meth) acrylic acid or hydroxypropyl of (meth) acrylic acid. It is an ester, more preferably a hydroxyethyl ester of (meth) acrylic acid, and specifically, a hydroxyethyl acrylate or a hydroxypropyl acrylate.

The hydroxyalkyl ester (c) of the unsaturated carboxylic acid may be of only one type or of two or more types.

In the copolymer (A1), in addition to the structural unit (I) and the structural unit (II) and / or the structural unit (III), the structural unit (IV) derived from the unsaturated carboxylic acid-based monomer (d) And / or other structural units (V) derived from the monomer (e) may be included. Specific examples of the unsaturated carboxylic acid-based monomer (d) will be described later.

The other monomer (e) is a monomer copolymerizable with the monomer (a), the monomer (b), the monomer (c), and the monomer (d). The other monomer (e) may be only one kind or two or more kinds.

Examples of the other monomer (e) include an alkoxy (poly) alkylene glycol obtained by adding an average of 1 to 500 mol of an alkylene oxide having 2 to 18 carbon atoms to an alcohol having 1 to 30 carbon atoms and (meth). Esters with unsaturated monocarboxylic acids such as acrylic acid and crotonic acid; Esters with unsaturated monocarboxylic acids such as methyl (meth) acrylate and glycidyl (meth) acrylate and alcohols with 1 to 30 carbon atoms; ( Half esters of unsaturated dicarboxylic acids such as (anhydrous) maleic acid, fumaric acid and itaconic acid with alcohols having 1 to 30 carbon atoms; unsaturated dicarboxylic acids such as (anhydrous) maleic acid, fumaric acid and itaconic acid and carbon. Diesters with alcohols having 1 to 30 atoms; Diamides of unsaturated dicarboxylic acids and amines having 1 to 30 carbon atoms; alkylene oxides having 2 to 18 carbon atoms on average 1 to 500 in the alcohols and amines. Half-esters of molar-added alkoxy (poly) alkylene glycol and the unsaturated dicarboxylic acids; alkoxy (poly) alkylene obtained by adding an average of 1 to 500 mol of alkylene oxide having 2 to 18 carbon atoms to the alcohol or amine. Diesters of glycols and unsaturated dicarboxylic acids; Half esters of unsaturated dicarboxylic acids and glycols with 2 to 18 carbon atoms or polyalkylene glycols with an average addition molar number of 2 to 500 of these glycols; Diesters of saturated dicarboxylic acids and glycols with 2 to 18 carbon atoms or polyalkylene glycols with an average addition molar number of 2 to 500 of these glycols; (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (Poly) alkylene glycol di (meth) acrylates such as (meth) acrylates; polyfunctional (meth) acrylates such as hexanediol di (meth) acrylates and trimethylpropantri (meth) acrylates; polyethylene glycol dimalates and the like. (Poly) alkylene glycol dimalates; unsaturated sulfonic acids (salts) such as vinyl sulfonate, (meth) allyl sulfonate, 2-methylpropanesulfonic acid (meth) acrylamide, styrenesulfonic acid; styrene, α-methylstyrene, Vinyl aromatics such as vinyl toluene; alcandiol mono (meth) acrylates such as 1,4-butanediol mono (meth) acrylate; Dienes such as tadiene and isoprene; unsaturated cyanides such as (meth) acrylonitrile; unsaturated esters such as vinyl acetate; non-residuals such as aminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, vinylpyridine, etc. Saturated amines; divinyl aromatics such as divinylbenzene; allyls such as (meth) allyl alcohol and glycidyl (meth) allyl ether; and the like. Examples of the salt referred to here include alkali metal salts, alkaline earth metal salts, ammonium salts, organic ammonium salts, and organic amine salts. Examples of the alkali metal salt include lithium salt, sodium salt, potassium salt and the like. Examples of the alkaline earth metal salt include calcium salt and magnesium salt. Examples of the organic ammonium salt include methylammonium salt, ethylammonium salt, dimethylammonium salt, diethylammonium salt, trimethylammonium salt, triethylammonium salt and the like. Examples of the organic amine salt include alkanolamine salts such as ethanolamine salt, diethanolamine salt, triethanolamine salt, and triisopropanolamine salt.

The content ratio of the structural unit having a carboxyl group or a salt thereof to the total structural units constituting the copolymer (A1) is preferably less than 20 mol%, preferably 0 mol% to 15 mol%. Yes, more preferably 0 mol% to 10 mol%, further preferably 0 mol% to 5 mol%, and particularly preferably 0 mol% to 3 mol%. When the content ratio of the structural unit having a carboxyl group or a salt thereof to all the structural units constituting the copolymer (A1) is within the above range, the cement admixture of the present invention has the strength of the cured product of the cement composition. Can be improved more significantly over the long term. The "carboxyl group or a salt thereof" here is a group represented by -COOM, and M is a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group, an organic ammonium group, or an organic amine group. ..

When the polymer (A1) contains structural units derived from other copolymerizable monomers, the total content of the structural unit (I) and the structural unit (II) and / or the structural unit (III) is determined. It is preferable that the structural unit constituting the polymer is the main component, and the structural unit (I) and the structural unit (II) and / or the structural unit (III) in the copolymer (A1) The total content of the above is preferably 51% by mass to 100% by mass, more preferably 70% by mass to 100% by mass, still more preferably 90% by mass to 100% by mass, and particularly preferably 95% by mass. % To 100% by mass, most preferably substantially 100% by mass. When the total content ratio of the structural unit (I) and the structural unit (II) and / or the structural unit (III) in the copolymer (A1) is within the above range, the cement admixture of the present invention can be used. The strength of the cured product of the cement composition can be improved more significantly over the long term.

The content ratio of the structural unit (I) and the structural unit (II) and / or the structural unit (III) in the copolymer (A1) is the structural unit (I) / structural unit (II) and / or the structural unit. The mass ratio of (III) is preferably 99/1% by weight to 1/99% by weight, more preferably 98/2% by weight to 5/95% by weight, and further preferably 95/5% by weight to 95% by weight. It is 10/90% by weight, particularly preferably 93/7% by weight to 20/80% by weight, and most preferably 90/10% by weight to 30/70% by weight. When the content ratio of the structural unit (I) and the structural unit (II) and / or the structural unit (III) in the copolymer (A1) is within the above range, the cement admixture of the present invention is a cement. The strength of the cured product of the composition can be improved more significantly over the long term.

The content ratio of each structural unit in the copolymer (A1) can be known by, for example, various structural analyzes (for example, NMR) of the copolymer (A1). Further, the structure derived from the monomer is calculated based on the amount of each monomer used in producing the copolymer (A1) and the polymerization rate without performing various structural analyzes as described above. The content ratio of the unit may be used as the content ratio of each structural unit in the copolymer (A1).

When determining the content ratio of the structural unit in the copolymer (A1), if the structural unit has a carboxyl group, the calculation is performed assuming that the structural unit is completely neutralized (sodium salt).

The mass average molecular weight (Mw) of the copolymer (A1) is preferably 3000 or more, more preferably 4000 to 1000000, further preferably 5000 to 500000, particularly preferably 1000 to 300000, and most preferably. It is preferably 30,000 to 200,000. When the mass average molecular weight (Mw) of the copolymer (A1) is within the above range, the cement admixture of the present invention can significantly improve the strength of the cured product of the cement composition over a long period of time.

The copolymer (A1) can be produced by any suitable method as long as the effects of the present invention are not impaired. The copolymer (A1) is preferably composed of an unsaturated polyalkylene glycol ether-based monomer (a) and an unsaturated amide-based monomer (b) and / or a hydroxyalkyl ester of an unsaturated carboxylic acid (c). It can be produced by polymerizing a monomer component containing the above in the presence of a polymerization initiator.

An unsaturated polyalkylene glycol ether-based monomer (a), an unsaturated amide-based monomer (b) and / or a hydroxyalkyl ester of an unsaturated carboxylic acid (c), which can be used for producing the copolymer (A1), And, if necessary, the amount of the structural unit (IV) and / or the other monomer (e) derived from the unsaturated carboxylic acid-based monomer (d) constitutes the copolymer (A1). It may be appropriately adjusted so that the ratio of the structural units derived from each monomer in the total structural units is as described above.

The polymerization of the monomer component can be carried out by any suitable method. For example, solution polymerization and bulk polymerization can be mentioned. Examples of the solution polymerization method include batch type and continuous type. Solvents that can be used in solution polymerization include water; alcohols such as methyl alcohol, ethyl alcohol, and isopropyl alcohol; aromatic or aliphatic hydrocarbons such as benzene, toluene, xylene, cyclohexane, and n-hexane; and esters such as ethyl acetate. Compounds; ketone compounds such as acetone and methyl ethyl ketone; cyclic ether compounds such as tetrahydrofuran and dioxane; and the like.

When the monomer component is polymerized, the polymerization initiator is a water-soluble polymerization initiator, for example, persulfate such as ammonium persulfate, sodium persulfate, potassium persulfate; hydrogen peroxide; 2,2'-. Azobisin compounds such as azobis-2-methylpropionamidine hydrochloride, cyclic azoamidin compounds such as 2,2'-azobis-2- (2-imidazolin-2-yl) propane hydrochloride, 2-carbamoyl azoisobutyronitrile and the like. A water-soluble azo-based initiator such as the azonitrile compound of the above; etc. can be used. These polymerization initiators include alkali metal sulfites such as sodium hydrogen sulfite, Fe (II) salts such as metadiosulfate, sodium hypophosphite, and molle salts, sodium hydroxymethanesulfinate dihydrate, and hydroxylamine hydrochloride. Accelerators such as salt, thiourea, L-ascorbic acid (salt), and elisorbic acid (salt) can also be used in combination. Among these combined forms, a combination of hydrogen peroxide and an accelerator such as L-ascorbic acid (salt) is preferable. These polymerization initiators and accelerators may be used alone or in combination of two or more.

When solution polymerization is performed using a lower alcohol, aromatic hydrocarbon, aliphatic hydrocarbon, ester compound, or ketone compound as a solvent, or when bulk polymerization is performed, benzoylper oxide or lauroylper is used as a polymerization initiator. Peroxides such as oxides and sodium peroxides; hydroperoxides such as t-butylhydroperoxides and cumenehydroperoxides; azo compounds such as azobisisobutyronitrile; and the like can be used. When such a polymerization initiator is used, an accelerator such as an amine compound can also be used in combination. Further, when a water-lower alcohol mixed solvent is used, it can be appropriately selected and used from the above-mentioned various polymerization initiators or combinations of the polymerization initiator and the accelerator.

The reaction temperature at the time of polymerization of the monomer component is appropriately determined by the polymerization method, solvent, polymerization initiator, and chain transfer agent used. Such a reaction temperature is preferably 0 ° C. or higher, more preferably 30 ° C. or higher, further preferably 50 ° C. or higher, and preferably 150 ° C. or lower, more preferably 120 ° C. or lower. It is more preferably 100 ° C. or lower.

Any suitable method can be adopted as the method for charging the monomer component into the reaction vessel. Examples of such a charging method include a method in which the entire amount is initially charged into the reaction vessel, a method in which the entire amount is divided or continuously charged into the reaction vessel, a part is initially charged into the reaction vessel, and the rest is charged into the reaction vessel. Examples thereof include a method of dividing or continuously feeding. Specifically, a method of continuously charging the total amount of the monomer (a) and the total amount of the monomer (b) and / or the monomer (c) into the reaction vessel, a part of the monomer (a). Is initially charged into the reaction vessel, and the remainder of the monomer (a) and the total amount of the monomer (b) and / or the monomer (c) are continuously charged into the reaction vessel, the monomer (a). ) And a part of the monomer (b) and / or a part of the monomer (c) are initially charged into the reaction vessel, and the rest of the monomer (a) and the monomer (b) and / Alternatively, a method in which the rest of the monomer (c) is alternately charged into the reaction vessel in several batches and the like can be mentioned. Further, by continuously or stepwise changing the charging rate of each monomer into the reaction vessel during the reaction, the charging mass ratio of each monomer per unit time is continuously or stepwise changed. Two or more copolymers having different ratios of the structural unit (I) and the structural unit (II) and / or the structural unit (III) may be synthesized at the same time during the polymerization reaction. The polymerization initiator may be charged into the reaction vessel from the beginning, may be added dropwise to the reaction vessel, or these may be combined depending on the intended purpose.

When polymerizing the monomer component, a chain transfer agent can be preferably used. When a chain transfer agent is used, it becomes easy to adjust the molecular weight of the obtained copolymer. Only one type of chain transfer agent may be used, or two or more types may be used.

As the chain transfer agent, any suitable chain transfer agent may be adopted. Examples of such a chain transfer agent include thiol-based chain transfer agents such as mercaptoethanol, thioglycerol, thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thioapple acid, and 2-mercaptoethanesulfonic acid; Secondary alcohols such as isopropanol; phosphite, hypophosphoric acid, and salts thereof (sodium bisulfite, potassium hypophosphate, etc.), sulfite, hydrogen sulfite, dithionic acid, metabisulfite, And lower oxides and salts thereof (sodium bisulfite, potassium sulfite, sodium hydrogen sulfite, potassium hydrogen sulfite, sodium bisulfite, potassium bisulfite, sodium metabisulfite, potassium metabisulfite, etc.), etc. Can be mentioned.

The produced copolymer (A1) can be used as it is as a copolymer (A1), but from the viewpoint of handleability, the pH of the reaction solution after the production of the copolymer (A1) is set to 5 or more. It is preferable to adjust it. However, in order to improve the polymerization rate, it is preferable to carry out the polymerization at a pH of less than 5, and adjust the pH to 5 or more after the polymerization. The pH can be adjusted by using, for example, an inorganic salt such as a hydroxide or carbonate of a monovalent metal or a divalent metal; an alkaline substance such as ammonia; an organic amine;

The concentration of the produced copolymer (A1) can be adjusted, if necessary, with respect to the solution obtained by the production.

The produced copolymer (A1) may be used as it is in the form of a solution, or it may be neutralized with a hydroxide of a divalent metal such as calcium or magnesium to form a polyvalent metal salt, and then dried. It may be powdered and used by allowing it to be powdered or by supporting it on an inorganic powder such as a silica-based fine powder and drying it.

<Polymer (A2)>
The polymer (A2) is a polymer having a structural unit derived from an alkylene oxide adduct of an unsaturated carboxylic acid.

The structural unit derived from the alkylene oxide adduct of unsaturated carboxylic acid is specifically -CC in which the unsaturated double bond (C = C) contained in the alkylene oxide adduct of unsaturated carboxylic acid is polymerized. It is a structural unit that has become −.

Examples of unsaturated carboxylic acids include monocarboxylic acids such as (meth) acrylic acid and crotonic acid; dicarboxylic acids such as maleic acid, itaconic acid and fumaric acid; and dicarboxylic acids such as maleic acid, itaconic acid and fumaric acid. Quantitative anhydrides; and the like.

The unsaturated carboxylic acid is preferably a monocarboxylic acid-based monomer such as (meth) acrylic acid or crotonic acid, and more preferably (meth) acrylic, in that the effects of the present invention can be more exhibited. It is an acid.

The unsaturated carboxylic acid may be only one kind or two or more kinds.

The alkylene oxide adduct of an unsaturated carboxylic acid is one in which an alkylene oxide is added to the carboxyl group-COOH of an unsaturated carboxylic acid, and when the alkylene oxide is AO and the average number of moles is t, it is -COO- (AO). It is represented by _{t H.}

The alkylene oxide is preferably an alkylene oxide having 2 to 18 carbon atoms, more preferably an alkylene oxide having 2 to 8 carbon atoms, and further preferably an alkylene oxide having 2 to 4 carbon atoms. is there. When the alkylene oxide is any two or more kinds selected from ethylene oxide, propylene oxide, butylene oxide, styrene oxide and the like, the addition form of the alkylene oxide is any of random addition, block addition, alternating addition and the like. It may be in the form. In order to secure a balance between hydrophilicity and hydrophobicity, ethylene oxide is preferably contained as an essential component in the alkylene oxide, and more preferably 50 mol% or more of the total alkylene oxide is ethylene oxide, and the whole alkylene oxide. It is more preferable that 90 mol% or more is ethylene oxide, 95 mol% or more of the total alkylene oxide is ethylene oxide, and 100 mol% of the total alkylene oxide is ethylene oxide most preferably.

The average number of moles of alkylene oxide added is preferably 2 to 300, more preferably 4 to 150, still more preferably 5 to 100, and particularly preferably 8 to 50. By adjusting the average number of moles of alkylene oxide added within the above range, the cement admixture of the present invention can improve the strength of the cured product of the cement composition more remarkably over a long period of time.

The polymer (A2) is an unsaturated polyalkylene glycol ether-based monomer (a) as a structural unit derived from other copolymerizable monomers in addition to the structural unit derived from the alkylene oxide adduct of unsaturated carboxylic acid. ) Derived structural unit (I), unsaturated amide monomer (b) derived structural unit (II), unsaturated carboxylic acid hydroxyalkyl ester (c) derived structural unit (III), unsaturated carboxylic acid It may contain either a structural unit (IV) derived from the system monomer (d) or a structural unit (V) derived from another monomer (e). Specific examples of each monomer are as described above or described later.

When the polymer (A2) contains a structural unit other than the structural unit derived from the alkylene oxide adduct of unsaturated carboxylic acid, the structural unit having a carboxyl group or a salt thereof with respect to all the structural units constituting the polymer (A2). The content of is preferably less than 20 mol%, preferably 0 mol% to 15 mol%, more preferably 0 mol% to 10 mol%, still more preferably 0 mol% to 5 mol%. Yes, particularly preferably 0 mol% to 3 mol%. When the content ratio of the structural unit having a carboxyl group or a salt thereof to all the structural units constituting the polymer (A2) is within the above range, the cement admixture of the present invention can increase the strength of the cured product of the cement composition. It can be improved more significantly over the long term. The "carboxyl group or a salt thereof" here is a group represented by -COOM, and M is a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group, an organic ammonium group, or an organic amine group. ..

When the polymer (A2) contains structural units derived from other copolymerizable monomers, the structural units derived from the alkylene oxide adduct of unsaturated carboxylic acid are the main components among the structural units constituting the polymer. The content ratio of the structural unit derived from the alkylene oxide adduct of the unsaturated carboxylic acid in the polymer (A2) is preferably 51% by mass to 100% by mass, more preferably. It is 70% by mass to 100% by mass, more preferably 90% by mass to 100% by mass, particularly preferably 95% by mass to 100% by mass, and most preferably substantially 100% by mass. Since the content ratio of the structural unit derived from the alkylene oxide adduct of the unsaturated carboxylic acid in the polymer (A2) is within the above range, the cement admixture of the present invention has a long-term strength of the cured product of the cement composition. Can be improved more significantly over.

The content ratio of each structural unit in the polymer (A2) can be known by, for example, various structural analyzes (for example, NMR) of the polymer (A2). Further, a structural unit derived from the monomer is calculated based on the amount of each monomer used in producing the polymer (A2) and the polymerization rate without performing various structural analyzes as described above. The content ratio of each structural unit in the polymer (A2) may be used as the content ratio of.

When determining the content ratio of the structural unit in the polymer (A2), if the structural unit has a carboxyl group, the calculation is performed assuming that the structural unit is completely neutralized (sodium salt).

The mass average molecular weight (Mw) of the polymer (A2) is preferably 3000 or more, more preferably 4000 to 1000000, further preferably 5000 to 500000, particularly preferably 1000 to 300000, and most preferably. Is 30,000 to 200,000. When the mass average molecular weight (Mw) of the polymer (A2) is within the above range, the cement admixture of the present invention can significantly improve the strength of the cured product of the cement composition over a long period of time.

<alkylene oxide adduct of trihydric or higher polyhydric alcohol (A3)>
The alkylene oxide adduct (A3) of a trihydric or higher polyhydric alcohol is a compound obtained by adding an alkylene oxide to a trihydric or higher polyhydric alcohol.

The trihydric or higher polyhydric alcohol may be a compound having 3 or more hydroxyl groups, a low molecular weight compound or a polymer, and any appropriate trivalent or higher valent alcohol as long as the effect of the present invention is not impaired. Polyhydric alcohol can be adopted. Such a trihydric or higher polyhydric alcohol is preferably a trihydric to 500 valent alcohol, more preferably a trivalent to 100 valent alcohol, and even more preferably a trivalent to 50 valent alcohol. .. Examples of such a trihydric or higher polyhydric alcohol include glycerin and sorbitol.

The average number of moles of alkylene oxide added to 1 mol of trihydric or higher polyhydric alcohol is preferably 2 to 300, more preferably 5 to 150, still more preferably 10 to 100, and particularly preferably 20 to 100. It is 50. By adjusting the average number of moles of alkylene oxide added to 1 mol of trihydric or higher polyhydric alcohol within the above range, the cement admixture of the present invention significantly improves the strength of the cured product of the cement composition over a long period of time. I can let you.

The mass average molecular weight (Mw) of the alkylene oxide adduct (A3) of a trihydric or higher polyhydric alcohol is preferably 3000 or more, more preferably 4000 to 1000000, still more preferably 5000 to 500000, and particularly. It is preferably 1000 to 300,000, and most preferably 30,000 to 200,000. When the mass average molecular weight (Mw) of the alkylene oxide adduct (A3) of a trihydric or higher polyhydric alcohol is within the above range, the cement admixture of the present invention can increase the strength of the cured product of the cement composition over a long period of time. It can be improved more significantly.

<Polyalkylene glycol (A4)>
The polyalkylene glycol (A4) is represented by the general formula (3).
_{^{R 9 - (A 3 O)}} s -R 10 (3)

In the general formula (3), R ⁹ and R ¹⁰ represent the same or different hydrocarbon groups having 1 to 30 hydrogen atoms or carbon atoms. Examples of the hydrocarbon group having 1 to 30 carbon atoms include an alkyl group having 1 to 30 carbon atoms (aliphatic alkyl group and alicyclic alkyl group), an alkenyl group having 1 to 30 carbon atoms, and a carbon atom number. Examples thereof include an alkynyl group of 1 to 30 and an aromatic group having 6 to 30 carbon atoms. ^{R 9} and R ¹⁰ are preferably hydrogen atoms or hydrocarbon groups having 1 to 20 carbon atoms, and more preferably 1 to 1 hydrogen atoms or carbon atoms, in that the effects of the present invention can be further exhibited. It is 12 hydrocarbon groups, more preferably a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and particularly preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

In the general formula (3), A 3 ^O is an oxyalkylene group having 2 to 18 carbon atoms, preferably an oxyalkylene group having 2 to 8 carbon atoms, more preferably 2 to 4 carbon atoms It is an oxyalkylene group. Also, A 3 ^O is an oxyethylene group, oxypropylene group, oxybutylene group, in the case of any two or more selected from among such oxystyrene group, addition form of A 3 ^O is a random addition, block addition , Alternate addition, etc. may be used. In order to secure a balance between hydrophilicity and hydrophobicity, it is preferable that the oxyethylene group contains an oxyethylene group as an essential component, and 50 mol% or more of the total oxyalkylene group is an oxyethylene group. It is more preferable that 90 mol% or more of the total oxyalkylene group is an oxyethylene group, and 100 mol% or more of the total oxyalkylene group is particularly preferably an oxyethylene group. The oxyalkylene group may be one kind or two or more kinds.

In the general formula (3), s represents an average addition mol number of the oxyalkylene group represented by ^{A 3} O (sometimes referred to as "chain length") is from 70 to 30,000, preferably from 90 to 10,000 It is more preferably 100 to 5000, further preferably 200 to 3000, particularly preferably 300 to 1000, and most preferably 400 to 800. When s is within the above range, the cement admixture of the present invention can improve the strength of the cured product of the cement composition more remarkably over a long period of time.

The mass average molecular weight (Mw) of the polyalkylene glycol (A4) is preferably 3000 or more, more preferably 4000 to 1000000, further preferably 5000 to 500000, particularly preferably 1000 to 300000, and most preferably. It is preferably 30,000 to 200,000. When the mass average molecular weight (Mw) of the polyalkylene glycol (A4) is within the above range, the cement admixture of the present invention can improve the strength of the cured product of the cement composition more remarkably over a long period of time.

Examples of the polyalkylene glycol (A4) represented by the general formula (3) include polyethylene glycol and polypropylene glycol.

≪Alkanolamine compound (B) ≫
As the alkanolamine compound (B), any suitable alkanolamine compound can be adopted as long as the effects of the present invention are not impaired. Examples of such an alkanolamine compound include a low molecular weight alkanolamine compound and a high molecular weight alkanolamine compound.

Examples of the low-molecular-weight alkanolamine compound include monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, methylethanolamine, methylisopropanolamine, methyldiethanolamine, and methyldiisopropanolamine. Diethanolisopropanolamine, diisopropanolethanolamine, tetrahydroxyethylethylenediamine, N, N-bis (2-hydroxyethyl) 2-propanolamine, N, N-bis (2-hydroxypropyl) -N- (hydroxyethyl) amine, N, N-bis (2-hydroxyethyl) -N- (2-hydroxypropyl) amine, N, N, N', N'-tetrakis (2-hydroxypropyl) ethylenediamine, tris (2-hydroxybutyl) amine, And so on. Among these, preferred low-molecular-weight alkanolamine compounds include triisopropanolamine, N, N, N', N'-tetrakis (2-hydroxypropyl) ethylenediamine, and diisopropanolethanolamine. Other low-molecular-weight alkanolamine compounds include, for example, a monomer having a skeleton of triisopropanolamine.

Examples of the high molecular weight alkanolamine compound include alkanolamine having a structure in which a part of the alkanolamine is bonded to the polymer. Examples of such a polymer-type alkanolamine compound include a polymer having a skeleton of triisopropanolamine.

≪Dispersant (C) ≫
The dispersant (C) is at least one selected from a polycarboxylic acid-based dispersant (C1), a sulfonic acid-based dispersant (C2), and a phosphoric acid-based dispersant (C3).

The dispersant (C) can contribute to improving the dispersibility of the cement composition in the cement admixture of the present invention.

The polycarboxylic acid-based dispersant (C1) may be one type or two or more types.

The sulfonic acid-based dispersant (C2) may be one type or two or more types.

The phosphoric acid-based dispersant (C3) may be one type or two or more types.

<Polycarboxylic acid dispersant (C1)>
The polycarboxylic acid-based dispersant (C1) is a structural unit (I) derived from an unsaturated polyalkylene glycol ether-based monomer (a) represented by ^{the general formula (1): YO (A 1} O) _m R ^0. It is a polycarboxylic acid-based copolymer having a structural unit (IV) derived from the unsaturated carboxylic acid-based monomer (d).

The content ratio of the structural unit having a carboxyl group or a salt thereof with respect to all the structural units constituting the polycarboxylic acid-based dispersant (C1) is preferably 20 mol% or more, preferably 25 mol% to 90. It is mol%, more preferably 30 mol% to 85 mol%, further preferably 35 mol% to 80 mol%, and particularly preferably 40 mol% to 75 mol%. When the content ratio of the structural unit having a carboxyl group or a salt thereof to all the structural units constituting the polycarboxylic acid-based dispersant (C1) is within the above range, the cement admixture of the present invention disperses the cement composition. The sex can be improved more significantly. The "carboxyl group or a salt thereof" here is a group represented by -COOM, and M is a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group, an organic ammonium group, or an organic amine group. ..

General formula (1): The structural unit (I) derived from the unsaturated polyalkylene glycol ether-based monomer (a) represented by ^{YO (A 1} O) _m R ^{0 is specifically a general formula (1).} It is a structural unit in which the unsaturated double bond (C = C) of Y in the unsaturated polyalkylene glycol ether-based monomer (a) represented by 1) becomes −C—C− by the polymerization reaction.

General formula (1): For the structural unit (I) derived from the unsaturated polyalkylene glycol ether-based monomer (a) represented by ^{YO (A 1} O) _m R ^{0, <copolymer (A1)>} The explanation in the section of

The unsaturated carboxylic acid-based monomer (d) is represented by the general formula (4).

The structural unit (IV) derived from the unsaturated carboxylic acid-based monomer (d) represented by the general formula (4) is specifically represented by the following formula.

In general formula (4) and structural unit (IV), R ^11- R ¹³ represent the same or different hydrogen atoms, methyl groups, _{or-(CH 2} ) _z COM groups. The − (CH ₂ ) _z COM group may form an anhydride with _{the − (CH 2} ) _z COM group or other − (CH 2) z COM groups. z is an integer from 0 to 2.

M represents a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group, an organic ammonium group, or an organic amine group.

X represents a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group, an organic ammonium group, or an organic amine group.

Examples of the unsaturated carboxylic acid-based monomer (d) represented by the general formula (4) include monocarboxylic acid-based monomers such as (meth) acrylic acid and crotonic acid, or salts thereof; maleic acid, Dicarboxylic acid-based monomers such as itaconic acid and fumaric acid or salts thereof; anhydrides of dicarboxylic acid-based monomers such as maleic acid, itaconic acid and fumaric acid or salts thereof; and the like. Examples of the salt referred to here include alkali metal salts, alkaline earth metal salts, ammonium salts, organic ammonium salts, and organic amine salts.

Examples of the alkali metal salt include lithium salt, sodium salt, potassium salt and the like. Examples of the alkaline earth metal salt include calcium salt and magnesium salt.

Examples of the organic ammonium salt include methylammonium salt, ethylammonium salt, dimethylammonium salt, diethylammonium salt, trimethylammonium salt, triethylammonium salt and the like.

Examples of the organic amine salt include ethanolamine salt, diethanolamine salt, triethanolamine salt, monoisopropanolamine salt, diisopropanolamine salt, triisopropanolamine salt, hydroxyethyldiisopropanolamine salt, dihydroxyethylisopropanolamine salt, and tetrakis (dihydroxyethylisopropanolamine salt). Examples thereof include alkanolamine salts such as 2-hydroxypropyl) ethylenediamine and pentax (2-hydroxypropyl) diethylenetriamine. Among these, preferably diisopropanolamine salt, triisopropanolamine salt, hydroxyethyldiisopropanolamine salt, tetrakis (2-hydroxypropyl) ethylenediamine salt, pentakis (2-hydroxypropyl) diethylenetriamine salt are preferable. Triisopropanolamine salt and hydroxyethyldiisopropanolamine salt.

The unsaturated carboxylic acid-based monomer (d) represented by the general formula (4) is preferably (meth) acrylic acid, maleic acid, or maleic anhydride in that the effects of the present invention can be further exhibited. It is more preferably acrylic acid or maleic acid.

The unsaturated carboxylic acid-based monomer (d) represented by the general formula (4) may be of only one type or of two or more types.

The total content ratio of the structural unit (I) and the structural unit (IV) in the polycarboxylic acid-based dispersant (C1) should be the main component of the structural units constituting the copolymer. Is preferable, 51% by mass to 100% by mass, more preferably 70% by mass to 100% by mass, still more preferably 90% by mass to 100% by mass, and particularly preferably 95% by mass to 100% by mass. %, Most preferably substantially 100% by mass. When the total content ratio of the structural unit (I) and the structural unit (IV) in the polycarboxylic acid-based dispersant (C1) is within the above range, the cement admixture of the present invention has the dispersibility of the cement composition. Can contribute to the improvement of.

In addition to the structural unit (I) and the structural unit (IV), the polycarboxylic acid-based dispersant (C1) contains structural units (II) derived from the unsaturated amide-based monomer (b) and unsaturated carboxylic acids. It contains any of a structural unit (III) derived from the hydroxyalkyl ester (c), a structural unit derived from an alkylene oxide adduct of an unsaturated carboxylic acid, and a structural unit (V) derived from another monomer (e). May be good. Specific examples of each monomer are as described above.

The other monomer (e) is copolymerized with the monomer (a), the monomer (b), the monomer (c), the monomer (d), and the alkylene oxide adduct of the unsaturated carboxylic acid. It is a possible monomer. The other monomer (e) may be only one kind or two or more kinds.

The content ratio of each structural unit in the polycarboxylic acid-based dispersant (C1) can be known by, for example, various structural analyzes (for example, NMR) of the polycarboxylic acid-based dispersant (C1). Further, the monomer calculated based on the amount of each monomer used in producing the polycarboxylic acid-based dispersant (C1) and the polymerization rate without performing various structural analyzes as described above. The content ratio of the derived structural unit may be used as the content ratio of each structural unit in the polycarboxylic acid-based dispersant (C1).

The content ratio of the structural unit (I) in the polycarboxylic acid-based dispersant (C1) is preferably 60% by mass to 99% by mass, more preferably 65% by mass to 97% by mass, and further preferably 70. It is from mass% to 95% by mass, particularly preferably 75% by mass to 90% by mass, and most preferably 80% by mass to 85% by mass.

The content ratio of the structural unit (IV) in the polycarboxylic acid-based dispersant (C1) is preferably 1% by mass to 40% by mass, more preferably 3% by mass to 35% by mass, and further preferably 5. It is from mass% to 30% by mass, particularly preferably from 10% by mass to 25% by mass, and most preferably from 15% by mass to 20% by mass.

When determining the content ratio of structural units in the polycarboxylic acid-based dispersant (C1), if the structural unit has a carboxyl group, the calculation is performed assuming that it is completely neutralized (sodium salt). ..

The mass average molecular weight (Mw) of the polycarboxylic acid-based dispersant (C1) is preferably 1000 or more, more preferably 3000 to 500000, still more preferably 5000 to 300000, still more preferably 1000 to 250,000. It is more preferably 20000 to 20000, particularly preferably 30,000 to 150,000, and most preferably 40,000 to 100,000. When the mass average molecular weight (Mw) of the polycarboxylic acid-based dispersant (C1) is within the above range, the cement admixture of the present invention can contribute to the improvement of the dispersibility of the cement composition.

The polycarboxylic acid-based dispersant (C1) can be produced by any suitable method as long as the effects of the present invention are not impaired. Preferably, as the method for producing the polycarboxylic acid-based dispersant (C1), the above-mentioned method for producing the polycarboxylic acid-based copolymer (A1) can be incorporated.

<Sulfonic acid-based dispersant (C2)>
The sulfonic acid-based dispersant (C2) is a dispersant that develops dispersibility with respect to cement mainly by electrostatic repulsion caused by a sulfonic acid group, and any suitable sulfonic acid-based dispersant can be used. , It is preferable that the compound has an aromatic group in the molecule. Specifically, polyalkylaryl sulfonate-based sulfonic acid-based dispersants such as naphthalene sulfonic acid formaldehyde condensate, methyl naphthalene sulfonic acid formaldehyde condensate, anthracene sulfonic acid formaldehyde condensate, etc .; , Melamine formalin resin sulfonate sulfonic acid dispersant; aromatic amino sulfonate sulfonic acid dispersant such as aminoaryl sulfonic acid-phenol-formaldehyde condensate; lignin sulfonate, modified lignin sulfonate Lignin sulfonate-based sulfonic acid-based dispersant; polystyrene sulfonate-based sulfonic acid-based dispersant; and the like. In the case of concrete having a high water / cement ratio, a lignin sulfonate-based dispersant is preferably used, while in the case of concrete having a medium water / cement ratio, which requires higher water reduction performance, a lignin sulfonate-based dispersant is preferably used. , Polyalkylaryl sulfonate-based, melamine formalin resin sulfonate-based, aromatic amino sulfonate-based, polystyrene sulfonate-based dispersants and the like are preferably used.

<Phosphoric acid-based dispersant (C3)>
As the phosphoric acid-based dispersant (C3), any suitable phosphoric acid-based dispersant having a phosphoric acid group in the molecule can be used, and for example, the phosphoric acid-based dispersion described in JP-A-2006-52381. Agents, phosphoric acid-based dispersants described in JP-A-2008-517080, and the like can be mentioned.

≪≪Cement composition≫≫
The cement composition of the present invention is a cement composition containing a polyoxyalkylene compound (A), an alkanolamine compound (B), a dispersant (C), and cement.

The cement composition of the present invention preferably contains water and aggregate.

As the aggregate, any suitable aggregate such as fine aggregate (sand or the like) or coarse aggregate (crushed stone or the like) can be adopted. Examples of such aggregates include gravel, crushed stone, granulated slag, and recycled aggregate. Further, examples of such an aggregate include refractory aggregates such as silica stone, clay, zircon, high alumina, silicon carbide, graphite, chromium, chromog and magnesia.

The cement composition of the present invention may contain any suitable cement additive (material) as long as the effects of the present invention are not impaired. Examples of such a cement additive (material) include cement additives (materials) as exemplified in the following (1) to (12). As the blending amount of the cement additive (material), any appropriate blending amount can be adopted according to the type and purpose of the cement additive (material) to be used.

(1) Water-soluble polymer substances: nonionic cellulose ethers such as methyl cellulose, ethyl cellulose and carboxymethyl cellulose; polysaccharides produced by microbial fermentation such as yeast glucan, xanthan gum and β-1.3 glucan; polyacrylamide and the like. ..

(2) Polymer emulsion: A copolymer of various vinyl monomers such as alkyl (meth) acrylate.

(3) Curing retardant: oxycarboxylic acid such as gluconic acid, glucoheptonic acid, arabonic acid, malic acid, citric acid or a salt thereof; sugar and sugar alcohol; polyhydric alcohol such as glycerin; aminotri (methylenephosphonic acid) and the like Phosphonic acid and its derivatives, etc.

The ratio of the curing retarder to the compound (A) is preferably 1% by mass to 1000% by mass, more preferably 2% by mass to 700% by mass, and further preferably 5% by mass to 500% by mass. It is particularly preferably 10% by mass to 300% by mass, and most preferably 20% by mass to 200% by mass.

(4) Fast-strengthening agent / accelerator: soluble calcium salts such as calcium chloride, calcium nitrite, calcium nitrate, calcium bromide, calcium iodide; chlorides such as iron chloride and magnesium chloride; sulfates; potassium hydroxide; Sodium hydroxide; carbonate; thiosulfate; formate such as formic acid and calcium formate; alumina cement; calcium aluminate silicate and the like.

(5) Oxyalkylene-based defoaming agent: polyoxyalkylene alkyl ethers such as diethylene glycol heptyl ether; polyoxyalkylene acetylene ethers; (poly) oxyalkylene fatty acid esters; polyoxyalkylene sorbitan fatty acid esters; polyoxyalkylene alkyl (Aryl) ether sulfate ester salts; polyoxyalkylene alkyl phosphate esters; polyoxypropylene polyoxyethylene laurylamine (propylene oxide average 1 to 20 mol adduct, ethylene oxide average 1 to 20 mol adduct, etc.), alkylene oxide Polyoxyalkylene alkylamines such as amines derived from fatty acids obtained from the added hardened beef fat (propylene oxide average 1 to 20 mol additions, ethylene oxide average 1 to 20 mol additions, etc.); polyoxyalkylene amides and the like.

(6) Defoamers other than oxyalkylene-based: Mineral oil-based, oil-based, fatty acid-based, fatty acid ester-based, alcohol-based, amide-based, phosphoric acid ester-based, metal soap-based, silicone-based defoaming agents.

(7) AE agent: resin soap, saturated or unsaturated fatty acid, sodium hydroxystearate, lauryl sulfate, ABS (alkylbenzene sulfonic acid), alkane sulfonate, polyoxyethylene alkyl (phenyl) ether, polyoxyethylene alkyl (phenyl) ether Sulfate ester or salt thereof, polyoxyethylene alkyl (phenyl) ether phosphate ester or salt thereof, protein material, alkenyl sulfosuccinic acid, α-olefin sulfonate, etc.

(8) Other surfactants: Various anionic surfactants; various cationic surfactants such as alkyltrimethylammonium chloride; various nonionic surfactants; various amphoteric surfactants and the like.

(9) Waterproofing agent: fatty acid (salt), fatty acid ester, fat, silicone, paraffin, asphalt, wax, etc.

(10) Rust inhibitor: nitrite, phosphate, zinc oxide, etc.

(11) Crack reducing agent: polyoxyalkyl ether or the like.

(12) Expansion material; ettringite-based, coal-based, etc.

Other known cement additives (materials) include cement wetting agents, thickeners, separation reducing agents, coagulants, drying shrinkage reducing agents, strength enhancing agents, self-leveling agents, coloring agents, fungicides and the like. be able to. Only one kind of these known cement additives (materials) may be used, or two or more kinds thereof may be used.

As the cement contained in the cement composition of the present invention, any suitable cement can be adopted. Examples of such cement include Portoland cement (ordinary, early-strength, ultra-fast-strength, moderate heat, sulfate-resistant and each low-alkali form), various mixed cements (blast furnace cement, silica cement, fly ash cement), and the like. White Portoland cement, alumina cement, ultra-fast-hardening cement (1 clinker fast-hardening cement, 2 clinker fast-hardening cement, magnesium phosphate cement), grout cement, oil well cement, low heat-generating cement (low-heat-generating blast furnace cement, fly ash mixed low) Heat-generating blast furnace cement, belite-rich cement), ultra-high-strength cement, cement-based solidifying material, eco-cement (cement manufactured from one or more of municipal waste incineration ash and sewage sludge incineration ash). Further, fine powder such as blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica powder, limestone powder and gypsum may be added to the cement composition of the present invention. The cement contained in the cement composition of the present invention may be only one kind or two or more kinds.

In the cement composition of the present invention, any appropriate value can be set as the unit water amount per ^{1 m 3 of the cement composition, the amount of cement used, and the water / cement ratio.} Such values, preferably, unit water is ^{100kg / m 3 ~185kg / m 3} , the amount of cement used is ^{250kg / m 3 ~800kg / m 3} , water / cement ratio (mass ratio) = is 0.1 to 0.7, more preferably, a unit water amount is ^{120kg / m 3 ~175kg / m 3} , the amount of cement used is ^{270kg / m 3 ~800kg / m 3} , water / cement ratio ( Mass ratio) = 0.12 to 0.65. As described above, the cement composition of the present invention can be widely used from poor to rich concrete, and can be used for both high-strength concrete having a large unit cement amount ^{and poor concrete with a unit cement amount of 300 kg / m 3} or less. It is valid.

The cement composition of the present invention may be effective for ready-mixed concrete, concrete for secondary concrete products, concrete for centrifugal molding, concrete for vibration compaction, steam curing concrete, sprayed concrete and the like. The cement composition of the present invention includes medium-fluidity concrete (concrete with a slump value of 22 to 25 cm), high-fluidity concrete (concrete with a slump value of 25 cm or more and a slump flow value of 50 to 70 cm), self-filling concrete, and self. It can also be effective for mortar and concrete that require high fluidity such as leveling materials.

The cement composition of the present invention may be prepared by blending the constituent components by any appropriate method. For example, a method of kneading the constituents in a mixer can be mentioned.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples. Unless otherwise specified, the term "parts" means parts by mass, and the term "%" means% by mass.

<Mass average molecular weight analysis conditions>
-Columns used: TSKguardcolumnα + TSKgelα-5000 + TSKgelα-4000 + TSKgelα-3000 manufactured by Tosoh Corporation were connected and used one by one.
-Eluent: Sodium dihydrogen phosphate, 2H ₂ O: 62.4 g, disodium hydrogen phosphate, 12H ₂ O: 143.3 g in a solution dissolved in ion-exchanged water: 7794.3 g, acetonitrile: 2000 g Was used as a mixed solution.
-Detector: Triple detector "Model 302 light scattering detector" manufactured by Viscotek, 90 ° scattering angle for right angle light scattering, 7 ° scattering angle for low angle light scattering, 18 μL cell capacity, 670 nm wavelength.
-Standard sample: Polyethylene glycol SE-8 (Mw = l07000) manufactured by Tosoh Corporation was used, the dn / dC was 0.135 ml / g, and the refractive index of the eluent was 1.333, and the device constant was determined.
-Driving amount Standard sample: 100 μL of the solution dissolved in the above eluent was injected so that the polymer concentration was 0.2 vol%.
Sample: 100 μL of the solution dissolved in the above eluent was injected so that the polymer concentration became 1.0 vol%.
-Flow velocity: 0.8 ml / min
-Column temperature: 40 ° C

<Concrete test>
Ordinary Portoland cement (manufactured by Pacific Cement Co., Ltd.) as cement, land sand from Oigawa water system as fine aggregate, crushed stone from Qinghai as coarse aggregate, tap water as kneading water, cement: 301 ^{kg / m 3} , water: 160 kg / m ³ , fine aggregate: 821 kg / m ³ , coarse aggregate: 1002 kg / m ³ , fine aggregate ratio (fine aggregate / fine coarse aggregate + coarse aggregate) (volume ratio): 47%, water / cement ratio A concrete composition was prepared with a composition of (mass ratio) = 0.53. The materials used for the test, the forced kneading mixer, and the measuring instruments were adjusted in the above test temperature atmosphere so that the temperature of the concrete composition became the test temperature of 20 ° C., and the kneading and each measurement were performed as described above. The test was performed in a temperature atmosphere. Further, in order to avoid the influence of air bubbles in the concrete composition on the fluidity of the concrete composition, an air amount adjusting agent is used as necessary to adjust the air amount to 4.0 ± 0.5%. did.
Under the above conditions, concrete was produced using a forced kneading mixer with a kneading time of 90 seconds, and the slump value and the amount of air were measured. The slump value and the amount of air were measured in accordance with the Japanese Industrial Standards (JIS-A-1101, 1128). The amount of the cement admixture added was such that the slump value was 8 to 15 cm.

<Measurement of compressive strength>
After kneading, the flow value and the amount of air were measured to prepare a sample for a compressive strength test, and the compressive strength after 28 days was measured under the following conditions.
Specimen preparation: 100 mm x 200 mm
Specimen curing (28 days): Temperature approx. 20 ° C, humidity 60%, constant temperature and humidity constant air curing for 24 hours, then curing in water for 27 days Specimen polishing: Specimen surface polishing (using specimen polishing finishing machine)
Compressive strength measurement: Automatic compressive strength measuring device (Maekawa Mfg. Co., Ltd.)

[Manufacturing Example A-1]
80.0 g of ion-exchanged water was placed in a glass reaction vessel equipped with a Dimroth condenser, a stirrer with a Teflon (registered trademark) stirring blade and a stirring seal, a nitrogen introduction tube, and a temperature sensor, and nitrogen was stirred at 250 rpm. Was heated to 70 ° C. while introducing at 200 mL / min. Next, from 160.0 g of methacrylic acid supplemented with ethylene oxide (average number of moles of ethylene oxide added: PE350), 3.87 g of 3-mercaptopropionic acid, and 106.7 g of ion-exchanged water. The mixed solution was added dropwise over 4 hours, and at the same time, a mixed solution consisting of 0.749 g of ammonium persulfate and 48.71 g of ion-exchanged water was added dropwise over 5 hours. After the dropping was completed, the polymerization reaction was completed by keeping the temperature at 70 ° C. for 1 hour. Then, it was neutralized to pH 7 with an aqueous sodium hydroxide solution to obtain an aqueous solution of a polymer (A-1) having a mass average molecular weight (Mw) of 20000.

[Manufacturing Example A-2]
Instead of PE350, PE200 (manufactured by NOF CORPORATION, average number of moles of ethylene oxide added 4) was used for synthesis in the same manner as in A-1.

[Manufacturing Example A-3]
A glass reaction vessel equipped with a Dimroth condenser, a stirrer with a Teflon (registered trademark) stirrer and a stirrer seal, a nitrogen introduction tube, and a temperature sensor is charged with 103.7 g of ion-exchanged water and stirred at 250 rpm. The mixture was heated to 70 ° C. while introducing nitrogen at 200 mL / min. Next, a mixed solution consisting of 144 g of an ethylene oxide adduct of 3-methyl-3-buten-1-ol (average number of moles of ethylene oxide added: 50 mol), 16.0 g of hydroxyethyl acrylate, and 80.0 g of ion-exchanged water was prepared. Dropped over time, and at the same time, a mixed solution of 0.06 g of 3-mercaptopropionic acid and 40.2 g of ion-exchanged water and a mixed solution of 1.98 g of ammonium persulfate and 64.05 g of ion-exchanged water were added for 5 hours each. Dropped over. After the dropping was completed, the polymerization reaction was completed by keeping the temperature at 70 ° C. for 1 hour. The polymerization rate of the ethylene oxide adduct of 3-methyl-3-butene-1-ol was 80%, and the polymerization rate of hydroxyethyl acrylate was 99%. The obtained copolymer was neutralized to pH 7 with an aqueous sodium hydroxide solution to obtain an aqueous solution of the copolymer (A-3) having a mass average molecular weight (Mw) of 350,000. The copolymer composition ratio of the copolymer (A-3) was calculated from the polymerization rate of each raw material monomer. Specifically, the polymerization rate of 3-methyl-3-butene-1-ol was 80% with respect to 144 g of the ethylene oxide adduct used, and the polymerization rate was 99% with respect to 16 g of hydroxyethyl acrylate. The ethylene oxide adduct content of -1-ol can be calculated as 144 × 0.80 / (144 × 0.80 + 16 × 0.99) = 88%. Table 1 shows the copolymer composition ratio (mass%), copolymer composition ratio (mol%), and mass average molecular weight of the obtained polymer (A-3).

[Manufacturing Examples A-4 to A-8]
The copolymerization reaction was carried out according to Production Example A-3 or the method described in JP-A-2004-519406, and the copolymers A-4 to A having the copolymerization composition ratio and mass average molecular weight as shown in Table 1 were carried out. An aqueous solution of −8 was obtained.

[Manufacturing Example C-1]
Unsaturated polyalkylene glycol ether 134 in which 82.5 g of ion-exchanged water and an average of 50 mol of ethylene oxide are added to metallic alcohol in a glass reaction vessel equipped with a thermometer, a stirrer, a dropping funnel, a nitrogen introduction tube and a reflux condenser. 0.6 g was charged, the reactor was replaced with nitrogen under stirring, and the temperature was raised to 80 ° C. Next, an aqueous solution obtained by diluting 15.41 g of acrylic acid with 23.12 g of ion-exchanged water was added dropwise over 5 hours. At the same time, an aqueous solution prepared by dissolving 0.62 g of ammonium persulfate in 14.95 g of ion-exchanged water and 0.58 g of 3-mercaptopropionic acid in 28.24 g of ion-exchanged water was added dropwise over 5 hours. After completion of the dropping, stirring was continued at 80 ° C. for 1 hour to complete the polymerization reaction, and an aqueous solution of a polycarboxylic acid-based copolymer having a mass average molecular weight (Mw) of 32000 was obtained. The polymerization rate of the ethylene oxide adduct of metallic alcohol was 86%, and the polymerization rate of acrylic acid was 99%. A sodium hydroxide aqueous solution was added to the obtained polycarboxylic acid-based copolymer aqueous solution, and the mixture was neutralized to pH 7. In this way, a polycarboxylic acid-based dispersant (C-1) was obtained. The copolymer composition ratio of the copolymer (C-1) was calculated from the polymerization rate of each raw material. Specifically, from the polymerization rate of 86% with respect to the amount of ethylene oxide adduct used of 134.6 g and the polymerization rate of 99% with respect to 15.41 g of acrylic acid, the content ratio of ethylene oxide adduct of the polymer metalyl alcohol is 134. It can be calculated as .6 × 0.86 / (134.6 × 0.86 + 15.41 × 0.99 × 94/72) = 85%. (Acrylic acid is converted to sodium salt) The copolymer composition ratio (mass%), copolymer composition ratio (mol%), and mass average molecular weight of the obtained polymer (C-1) are shown in Table 2.

[Production Examples C-2 to C-4, C-7 to C-9]
The copolymerization reaction was carried out according to Production Example C-1 or the method described in JP-A-2004-519406, and the copolymers C-2 to C having the copolymerization composition ratio and mass average molecular weight as shown in Table 2 were carried out. An aqueous solution of -4, C-7 to C-9 was obtained.

[Manufacturing Example C-5]
The copolymerization reaction was carried out according to the method described in JP-A-2006-52381, and methoxypolyethylene glycol methacrylate (average number of molar additions of ethylene oxide: 23 mol), monophosphate (2-hydroxyethyl) methacrylic acid ester, and phosphoric acid. A phosphoric acid-based dispersant (C) containing a copolymer having a copolymer composition ratio of di- [2- (hydroxyethyl) methacrylic acid] of 30/47/23 (mol%) and a mass average molecular weight (Mw) of 20000. An aqueous solution of -5) was obtained.

[Manufacturing Example C-6]
The condensation reaction was carried out according to the method described in JP-A-2008-517080, and polyethylene glycol (average addition of ethylene oxide: 20 mol) by condensation of monophenyl ether and phenoxyethanol phosphate with formaldehyde. Number of moles: 20 mol) An aqueous solution of a phosphoric acid-based dispersant (C-6) containing a condensate having a monophenyl ether to phenoxyethanol phosphate ratio of 30/70 (mol%) and a mass average molecular weight (Mw) of 25,000. Obtained.

[Example 1]
As the polyoxyalkylene compound (A), PEG5000 (polyethylene glycol, manufactured by Aldrich, mass average molecular weight = 5000), as the alkanolamine compound (B), EDIPA (hydroxyethyldiisopropanolamine, manufactured by Aldrich), as the dispersant (C). A polycarboxylic acid-based dispersant (C-1) was used and blended as shown in Table 3 to prepare a cement admixture (1). The results are shown in Table 3.

[Example 2]
PEG20000 (polyethylene glycol, manufactured by Aldrich, mass average molecular weight = 20000) as the polyoxyalkylene compound (A), THEDA (N, N, N', N'-tetrakis (2-hydroxypropyl)) as the alkanolamine compound (B). Ethylenediamine (manufactured by Tokyo Kasei Co., Ltd.) and a polycarboxylic acid-based dispersant (C-2) as the dispersant (C) were used and blended as shown in Table 3 to prepare a cement admixture (2). The results are shown in Table 3.

[Example 3]
PEG1000000 (polyethylene glycol, manufactured by Wako Pure Chemical Industries, Ltd., mass average molecular weight = 1000000) as the polyoxyalkylene compound (A), EDIPA (hydroxyethyldiisopropanolamine, manufactured by Aldrich) as the alkanolamine compound (B), dispersant ( Mighty 150 (manufactured by Kao Co., Ltd.) was used as C) and blended as shown in Table 3 to prepare a cement admixture (3). The results are shown in Table 3.

[Example 4]
The copolymer (A-1) was used as the polyoxyalkylene compound (A), EDIPA (hydroxyethyldiisopropanolamine, manufactured by Aldrich) was used as the alkanolamine compound (B), and Master Pozoris No. was used as the dispersant (C). 8 (manufactured by BASF Japan Ltd.) was used and blended as shown in Table 3 to prepare a cement admixture (4). The results are shown in Table 3.

[Example 5]
The copolymer (A-2) as the polyoxyalkylene compound (A), TIPA (triisopropanolamine, manufactured by Wako Pure Chemical Industries, Ltd.) as the alkanolamine compound (B), and the polycarboxylic acid-based dispersant as the dispersant (C). (C-3) was used and blended as shown in Table 3 to prepare a cement admixture (5). The results are shown in Table 3.

[Example 6]
SB600 (mass average molecular weight = 26000, an average of 600 mol of ethylene oxide added to 1 mol of sorbitol) as the polyoxyalkylene compound (A), and THEDA (N, N, N', N) as the alkanolamine compound (B). '-Tetrax (2-hydroxypropyl) ethylenediamine, manufactured by Tokyo Kasei Co., Ltd., using a polycarboxylic acid-based dispersant (C-4) as the dispersant (C), and blending as shown in Table 3, a cement admixture ( 6) was prepared. The results are shown in Table 3.

[Example 7]
SB1000 as the polyoxyalkylene compound (A) (mass average molecular weight = 44,000, with an average of 1000 mol of ethylene oxide added to 1 mol of sorbitol), and TIPA (triisopropanolamine, Wako Pure Chemical Industries, Ltd.) as the alkanolamine compound (B). A phosphate-based dispersant (C-5) was used as the dispersant (C), and the mixture was blended as shown in Table 3 to prepare a cement admixture (7). The results are shown in Table 3.

[Example 8]
The copolymer (A-3) as the polyoxyalkylene compound (A), EDIPA (hydroxyethyldiisopropanolamine, manufactured by Aldrich) as the alkanolamine compound (B), and the phosphoric acid-based dispersant (C) as the dispersant (C). Using -6), the cement admixture (8) was prepared by blending as shown in Table 3. The results are shown in Table 3.

[Example 9]
Copolymer (A-4) as polyoxyalkylene compound (A), THEDA (N, N, N', N'-tetrakis (2-hydroxypropyl) ethylenediamine as alkanolamine compound (B), manufactured by Tokyo Kasei Co., Ltd.) , Mighty 150 (manufactured by Kao Corporation) was used as the dispersant (C) and blended as shown in Table 3 to prepare a cement admixture (9). The results are shown in Table 3.

[Example 10]
The copolymer (A-5) was used as the polyoxyalkylene compound (A), TIPA (triisopropanolamine, manufactured by Wako Pure Chemical Industries, Ltd.) was used as the alkanolamine compound (B), and Master Pozoris No. was used as the dispersant (C). 8 (manufactured by BASF Japan Ltd.) was used and blended as shown in Table 3 to prepare a cement admixture (10). The results are shown in Table 3.

[Example 11]
Copolymer (A-6) as polyoxyalkylene compound (A), THEDA (N, N, N', N'-tetrakis (2-hydroxypropyl) ethylenediamine as alkanolamine compound (B), manufactured by Tokyo Kasei Co., Ltd.) , Phosphoric acid-based dispersant (C-5) was used as the dispersant (C), and the mixture was blended as shown in Table 3 to prepare a cement admixture (11). The results are shown in Table 3.

[Example 12]
The polyoxyalkylene compound (A) is a copolymer (A-7), the alkanolamine compound (B) is EDIPA (hydroxyethyldiisopropanolamine, manufactured by Aldrich), and the dispersant (C) is a phosphoric acid-based dispersant (C). Using -6), the cement admixture (12) was prepared by blending as shown in Table 3. The results are shown in Table 3.

[Example 13]
The copolymer (A-8) as the polyoxyalkylene compound (A), TIPA (triisopropanolamine, manufactured by Wako Pure Chemical Industries, Ltd.) as the alkanolamine compound (B), and the polycarboxylic acid-based dispersant as the dispersant (C). (C-7) was used and blended as shown in Table 3 to prepare a cement admixture (13). The results are shown in Table 3.

[Example 14]
PEG20000 (polyethylene glycol, manufactured by Aldrich, mass average molecular weight = 20000) as the polyoxyalkylene compound (A), THEDA (N, N, N', N'-tetrakis (2-hydroxypropyl)) as the alkanolamine compound (B). Ethylenediamine (manufactured by Tokyo Kasei Co., Ltd.) and a polycarboxylic acid-based dispersant (C-8) as the dispersant (C) were used and blended as shown in Table 3 to prepare a cement admixture (14). The results are shown in Table 3.

[Example 15]
SB600 (mass average molecular weight = 26000, average 600 mol of ethylene oxide added to 1 mol of sorbitol), EDIPA (hydroxyethyldiisopropanolamine, manufactured by Aldrich), dispersant (C) as polyoxyalkylene compound (A) ), A polycarboxylic acid-based dispersant (C-9) was used, and the mixture was blended as shown in Table 3 to prepare a cement admixture (15). The results are shown in Table 3.

[Example 16]
The copolymer (A-1) as the polyoxyalkylene compound (A), TIPA (triisopropanolamine, manufactured by Wako Pure Chemical Industries, Ltd.) as the alkanolamine compound (B), and the polycarboxylic acid-based dispersant as the dispersant (C). (C-4) was used and blended as shown in Table 3 to prepare a cement admixture (16). The results are shown in Table 3.

[Example 17]
The copolymer (A-4) as the polyoxyalkylene compound (A), EDIPA (hydroxyethyldiisopropanolamine, manufactured by Aldrich) as the alkanolamine compound (B), and the polycarboxylic acid-based dispersant (C) as the dispersant (C). Using C-2), the cement admixture (17) was prepared by blending as shown in Table 3. The results are shown in Table 3.

[Example 18]
Copolymer (A-6) as polyoxyalkylene compound (A), THEDA (N, N, N', N'-tetrakis (2-hydroxypropyl) ethylenediamine as alkanolamine compound (B), manufactured by Tokyo Kasei Co., Ltd.) , Mighty 150 (manufactured by Kao Corporation) was used as the dispersant (C) and blended as shown in Table 3 to prepare a cement admixture (18). The results are shown in Table 3.

[Example 19]
The copolymer (A-3) as the polyoxyalkylene compound (A), EDIPA (hydroxyethyldiisopropanolamine, manufactured by Aldrich) as the alkanolamine compound (B), and the phosphoric acid-based dispersant (C) as the dispersant (C). -6) was used and blended as shown in Table 3 to prepare a cement admixture (19). The results are shown in Table 3.

[Example 20]
Copolymer (A-6) as polyoxyalkylene compound (A), THEDA (N, N, N', N'-tetrakis (2-hydroxypropyl) ethylenediamine as alkanolamine compound (B), manufactured by Tokyo Kasei Co., Ltd.) , A polycarboxylic acid-based dispersant (C-1) was used as the dispersant (C), and the mixture was blended as shown in Table 3 to prepare a cement admixture (20). The results are shown in Table 3.

[Example 21]
SB1000 as a polyoxyalkylene compound (A) (mass average molecular weight = 44000, an average of 1000 mol of ethylene oxide added to 1 mol of sorbitol), and TIPA (triisopropanolamine, Wako Pure Chemical Industries, Ltd.) as an alkanolamine compound (B). A polycarboxylic acid-based dispersant (C-8) was used as the dispersant (C), and the mixture was blended as shown in Table 3 to prepare a cement admixture (21). The results are shown in Table 3.

[Comparative Example 1]
As shown in Table 3, the polycarboxylic acid-based dispersant (C-2) was used as the cement admixture (C1). The results are shown in Table 3.

[Comparative Example 2]
As shown in Table 3, Mighty 150 (manufactured by Kao Corporation) was used as a cement admixture (C2). The results are shown in Table 3.

[Comparative Example 3]
As shown in Table 3, Master Pozoris No. 8 (manufactured by BASF Japan Ltd.) was used as a cement admixture (C3). The results are shown in Table 3.

[Comparative Example 4]
As shown in Table 3, the polycarboxylic acid-based dispersant (C-3) was used as the cement admixture (C4). The results are shown in Table 3.

[Comparative Example 5]
As shown in Table 3, the phosphoric acid-based dispersant (C-5) was used as the cement admixture (C5). The results are shown in Table 3.

As shown in Table 3, the 28-day compressive strengths of Examples 1 to 21 showed a remarkably excellent effect.

The cement admixture of the present invention is suitably used for cement compositions such as mortar and concrete.

Claims (2)

A cement admixture containing a polyoxyalkylene compound (A), an alkanolamine compound (B), and a dispersant (C).
The polyoxyalkylene compound (A)
(I) General formula (1): YO (A ¹ O) _{Unsaturated polyalkylene glycol ether-based monomer represented by m} R ⁰ (a) (In the general formula (1), Y has 2 carbon atoms. Represents an alkenyl group of ~ 8, R ⁰ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, A ¹ O represents an oxyalkylene group having 2 to 18 carbon atoms, and m represents A. ^{It represents the average number of moles of the oxyalkylene group represented by 1} O, and m is 2 to 300.) The structural unit (I) derived from the structural unit (I) and the unsaturated amide-based monomer (b) derived from the structural unit (II). ) And / or a copolymer (A1) having a structural unit (III) derived from the hydroxyalkyl ester (c) of an unsaturated carboxylic acid , and the structural unit (I) in the copolymer (A1). The copolymer (A1), wherein the total content of the structural unit (II) and / or the structural unit (III) is 95% by mass to 100% by mass.
(Ii) Polymer (A2) having a structural unit derived from an alkylene oxide adduct of unsaturated carboxylic acid,
(Iii) An alkylene oxide adduct (A3) of a trihydric or higher polyhydric alcohol,
(Iv) Polyalkylene glycol (A4),
At least one selected from
The dispersant (C)
(V) General formula (1): YO (A ¹ O) _{Unsaturated polyalkylene glycol ether-based monomer represented by m} R ⁰ (a) (In the general formula (1), Y has 2 carbon atoms. Represents an alkenyl group of ~ 8, R ⁰ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, A ¹ O represents an oxyalkylene group having 2 to 18 carbon atoms, and m represents A. ^{It represents the average number of moles of the oxyalkylene group represented by 1} O, and m is 2 to 300) -derived structural unit (I) and unsaturated carboxylic acid-based monomer (d) -derived structural unit (d). A polycarboxylic acid-based dispersant (C1) which is a polycarboxylic acid-based copolymer having IV), and the content ratio of the structural unit (IV) in the polycarboxylic acid-based dispersant (C1). However, the polycarboxylic acid-based dispersant (C1), which is 15% by mass to 40% by mass,
(Vii) Phosphoric acid-based dispersant (C3),
At least one selected from
Cement admixture. A cement composition containing a polyoxyalkylene compound (A), an alkanolamine compound (B), a dispersant (C), and cement.
The polyoxyalkylene compound (A)
(I) General formula (1): YO (A ¹ O) _{Unsaturated polyalkylene glycol ether-based monomer represented by m} R ⁰ (a) (In the general formula (1), Y has 2 carbon atoms. Represents an alkenyl group of ~ 8, R ⁰ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, A ¹ O represents an oxyalkylene group having 2 to 18 carbon atoms, and m represents A. ^{It represents the average number of moles of the oxyalkylene group represented by 1} O, and m is 2 to 300.) The structural unit (I) derived from the structural unit (I) and the unsaturated amide-based monomer (b) derived from the structural unit (II). ) And / or a copolymer (A1) having a structural unit (III) derived from the hydroxyalkyl ester (c) of an unsaturated carboxylic acid , and the structural unit (I) in the copolymer (A1). The copolymer (A1), wherein the total content of the structural unit (II) and / or the structural unit (III) is 95% by mass to 100% by mass.
(Ii) Polymer (A2) having a structural unit derived from an alkylene oxide adduct of unsaturated carboxylic acid,
(Iii) An alkylene oxide adduct (A3) of a trihydric or higher polyhydric alcohol,
(Iv) Polyalkylene glycol (A4),
At least one selected from
The dispersant (C)
(V) General formula (1): YO (A ¹ O) _{Unsaturated polyalkylene glycol ether-based monomer represented by m} R ⁰ (a) (In the general formula (1), Y has 2 carbon atoms. Represents an alkenyl group of ~ 8, R ⁰ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, A ¹ O represents an oxyalkylene group having 2 to 18 carbon atoms, and m represents A. ^{It represents the average number of moles of the oxyalkylene group represented by 1} O, and m is 2 to 300) -derived structural unit (I) and unsaturated carboxylic acid-based monomer (d) -derived structural unit (d). A polycarboxylic acid-based dispersant (C1) which is a polycarboxylic acid-based copolymer having IV), and the content ratio of the structural unit (IV) in the polycarboxylic acid-based dispersant (C1). However, the polycarboxylic acid-based dispersant (C1), which is 15% by mass to 40% by mass,
(Vii) Phosphoric acid-based dispersant (C3),
At least one selected from
Cement composition.