JP5898292B2 - Cement admixture and cement composition using the same - Google Patents

Description

  The present invention relates to a cement admixture and a cement composition using the same. More specifically, when mixed with a so-called cement composition (cement composition) such as cement paste, mortar, concrete, etc., it is excellent in water reduction and slump loss prevention performance, and can reduce the viscosity of the produced cement composition. The present invention relates to a cement admixture and a cement composition containing the cement admixture.

  In order to improve the workability and durability of concrete, it is effective to reduce the amount of unit water in the concrete. However, it is known that when the unit water amount is reduced, the fluidity of concrete is lowered and the workability is impaired. Therefore, in order to ensure efficient workability of the concrete even when the unit water amount is reduced, various dispersants having a function of dispersing cement particles are used.

  Examples of such dispersants include AE water reducing agents such as lignin sulfonic acid dispersants and oxycarboxylic acids; high performance AE water reducing agents such as naphthalene sulfonic acid dispersants, amino sulfonic acid dispersants and polycarboxylic acid dispersants. Agents (Patent Documents 1 to 4) are known. Among these, from the viewpoint of reducing environmental impact, the use of lignin sulfonic acid-based dispersants mainly composed of lignin sulfonates derived from natural products or their derivatives, and dispersants mainly composed of oxycarboxylic acids is again used. In the spotlight. In particular, lignin sulfonic acid-based dispersants are attracting attention because they lead to effective use of sulfite pulp cooking effluent and the like, and the effect of reducing environmental burdens is enhanced.

  These dispersants are required to have initial water-reducing properties and slump retention properties, and in recent years, there has been an increasing demand for slump retention properties. In concrete construction, after being manufactured at a production plant, it is transported to a construction site by a truck agitator car, unloaded from a pump car, and pumped to a placement site for construction. Therefore, it takes a long time from being manufactured to being placed on site. For this reason, unless the slump retainability is imparted to the concrete, the workability is significantly deteriorated. Although oxycarboxylic acid and lignin sulfonic acid-based dispersants are effective for initial water reduction, satisfactory performance cannot be obtained with respect to slump retention.

  For this reason, in order to improve the slump retention of cement compositions (cement paste, concrete, mortar, etc.), cement admixtures in which various dispersants are combined are used. For example, a cement admixture containing an ester of (meth) acrylic acid and a copolymer of α, β-unsaturated carboxylic acid and / or a salt thereof and lignin sulfonate in a predetermined ratio (Patent Document 5), Cement admixture in which a copolymer of a structural unit derived from a polyalkylene glycol monoalkenyl ether and a structural unit derived from an unsaturated monocarboxylic acid monomer is mixed with a sulfonic acid-based dispersant containing an aromatic group (Patent Document 6), a cement admixture (Patent Document 7) in which a copolymer of a polyalkylene glycol monoalkenyl ether and an unsaturated monocarboxylic acid monomer and an oxycarboxylic acid are mixed has been proposed.

JP-A-9-86990 JP 2005-281022 A JP-A-11-157898 JP 2003-146717 A International Publication No. WO99 / 62838 JP 2003-212624 A JP 2003-212622 A

  However, like cement admixtures described in Patent Documents 5 to 7, lignin sulfonic acid dispersants, oxycarboxylic acids and polycarboxylic dispersants (polyalkylene glycol monoalkenyl ether monomers and unsaturated monocarboxylic acids). When a copolymer with an acid monomer is used in combination, the adsorption of the polycarboxylic acid dispersant to the cement is hindered due to the difference in the adsorption property to each cement. In other words, when a lignin sulfonic acid dispersant and a polycarboxylic acid dispersant are used in combination, and an oxycarboxylic acid and a polycarboxylic dispersant are used together, the resulting admixture has sufficient cement dispersibility inherent in the polycarboxylic acid dispersant. Therefore, there is a problem that the slump retention property is also deteriorated. In order to improve cement dispersibility and slump retention, it can be solved by increasing the amount of cement admixture, but in this case, material separation of the concrete occurs, resulting in deterioration of workability and proper hardened concrete cannot be obtained. The problem arises.

  On the other hand, when these conventional cement admixtures are used, the viscosity of the cement composition increases. The increase in the viscosity of the cement composition significantly deteriorates the workability of the cement composition, increases the energy loss from concrete production to placement, and increases the environmental load. Moreover, the increase in the viscosity of the cement composition is not enough to fill the concrete at the time of placing, and causes the strength of the hardened concrete to be reduced.

  Therefore, in the present invention, in order to solve the above-mentioned problems, it has excellent cement dispersibility and slump retainability, can reduce the viscosity of the cement composition and improve workability (workability), and environment. An object of the present invention is to provide a cement admixture capable of reducing the load and a cement composition using the same.

  As a result of intensive studies to achieve the above object, the present inventors have found that the first polycarboxylic acid copolymer or a salt thereof (A) containing a structural unit having an alkenyl group having a specific number of carbon atoms. The second polycarboxylic acid copolymer containing a specific unsaturated carboxylic acid ester structural unit or a salt thereof (B), a sulfonic acid compound (C), an oxycarboxylic acid or a sugar (D) was mixed. The present inventors have found that the above problems can be solved by using a cement admixture, and have reached the present invention.

（式中、Ｒ¹は、炭素原子数２〜５のアルケニル基を表す。Ａ¹Ｏは、同一若しくは異なって、炭素原子数２〜１８のオキシアルキレン基を表す。ｎ１は、オキシアルキレン基の平均付加モル数であり、１〜８０の数を表す。Ｒ²は、水素原子または炭素原子数１〜３０の炭化水素基を表す。）

（式中、Ｒ³、Ｒ⁴およびＲ⁵は、それぞれ独立に、水素原子または炭素原子数１〜３のアルキル基を表す。ｍは、０〜２の数を表す。Ａ²Ｏは、同一若しくは異なって、炭素原子数２〜１８のオキシアルキレン基を表す。ｎ２は、オキシアルキレン基の平均付加モル数であり、１〜８０の数を表す。Ｘは、水素原子または炭素原子数１〜３０の炭化水素基を表す。） That is, the present invention includes the following [1] to [12].
[1] Monomer (I) represented by the following general formula (1) 5 to 95% by weight, unsaturated monocarboxylic acid monomer (II) 1 to 50% by weight, and monomer (I ) And / or (II) copolymerizable monomer (III), a polycarboxylic acid copolymer obtained by copolymerizing a monomer containing 0 to 10% by weight or a salt thereof (A) And 5 to 95% by weight of monomer (IV) represented by the following general formula (2), 1 to 50% by weight of unsaturated monocarboxylic acid monomer (II), and monomer (II) And / or a polycarboxylic acid copolymer obtained by copolymerizing a monomer containing 0 to 10% by weight of a monomer (V) copolymerizable with (IV) or a salt thereof (B) A cement admixture comprising a sulfonic acid compound (C) and an oxycarboxylic acid or sugar (D) The content ratios of (A), (B), (C) and (D) are (A) :( B) :( C) :( D) = 1 to 90% by weight: 1 to 90% by weight. %: 1 to 90% by weight: 1 to 90% by weight (provided that (A) + (B) + (C) + (D) = 100% by weight).

(In the formula, R ¹ represents an alkenyl group having 2 to 5 carbon atoms. A ¹ O is the same or different and represents an oxyalkylene group having 2 to 18 carbon atoms. N1 represents an oxyalkylene group. (The average number of moles added represents a number of 1 to 80. R ² represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms.)

(In the formula, R ³ , R ⁴ and R ⁵ each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. M represents a number of 0 to ^2. A ² O is the same. Or, differently, it represents an oxyalkylene group having 2 to 18 carbon atoms, n2 is the average number of added moles of the oxyalkylene group, and represents a number of 1 to 80. X is a hydrogen atom or 1 to 1 carbon atoms. Represents 30 hydrocarbon groups.)

[2] The cement admixture according to [1], wherein the monomer (III) and / or (V) includes a (meth) allylbisphenol monomer.
[3] The cement admixture according to the above [1] or [2], wherein the polycarboxylic acid copolymer or salt (A) thereof has a weight average molecular weight of 5000 to 50000 in terms of polyethylene glycol.
[4] The polycarboxylic acid copolymer or salt (A) thereof is a salt obtained by neutralizing the copolymer with an alkaline substance, according to any one of [1] to [3]. Cement admixture.
[5] The polycarboxylic acid copolymer or the salt (B) thereof is a salt obtained by neutralizing the copolymer with an alkaline substance, according to any one of [1] to [4]. Cement admixture.
[6] The cement admixture according to any one of [1] to [5], wherein the sulfonic acid compound (C) has a sulfonic acid group in the molecule.
[7] The cement admixture according to any one of [1] to [6], wherein the sulfonic acid compound (C) has an aromatic group in the molecule.
[8] The cement admixture according to any one of [1] to [7], further containing a (poly) alkylene glycol alkenyl ether monomer (E).
[9] The content of the (poly) alkylene glycol alkenyl ether monomer (E) is 1 to 90% by weight with respect to the polycarboxylic acid copolymer or salt (A) thereof [8] The cement admixture described in 1.
[10] The cement admixture according to any one of [1] to [8], further containing a water-soluble polyalkylene glycol (F) in which both terminal groups are hydrogen atoms.
[11] The content of the water-soluble polyalkylene glycol (F) in which both terminal groups are hydrogen atoms is less than 1% by weight based on the polycarboxylic acid copolymer or salt (A) thereof [ [10] The cement admixture according to [10].
[12] A cement composition containing the cement admixture according to any one of [1] to [11].

  According to the present invention, when a cement composition is used, it has excellent cement dispersibility and slump retention, can suppress the viscosity of the cement composition, improve workability, and reduce environmental load. A cement admixture and a cement composition using the same are provided.

  The cement dispersant of the present invention comprises a polycarboxylic acid copolymer or a salt thereof (A), a polycarboxylic acid copolymer or a salt thereof (B), a sulfonic acid compound (C), and an oxycarboxylic acid or It is a cement admixture having sugar (D) in a predetermined ratio.

  The polycarboxylic acid copolymer or its salt (A) is composed of 5 to 95% by weight of the monomer (I) represented by the general formula (1), 1 to 1 of the unsaturated monocarboxylic acid monomer (II) 1 to It is obtained by copolymerizing 50% by weight of a monomer containing 0 to 10% by weight of monomer (III) copolymerizable with monomer (I) and / or (II). The copolymer has a structural unit derived from the monomer (I), a structural unit derived from the monomer (II), and a structural unit derived from the monomer (III) as essential structural units. It is a polymer.

  The blending ratio of each monomer in obtaining the polycarboxylic acid copolymer or salt (A) is as follows. The blending ratio of the monomer (I) is 5% to 95% by weight, preferably 20% to 95% by weight, more preferably 30% to 95% by weight, and still more preferably 40% to 95%. % By weight, still more preferably 50% by weight to 95% by weight, particularly preferably 60% by weight to 95% by weight, most preferably 70% by weight to 95% by weight. The blending ratio of the monomer (II) is 1% to 50% by weight, preferably 2% to 40% by weight, more preferably 5% to 30% by weight, and still more preferably 7%. % By weight to 25% by weight. The blending ratio of the monomer (III) is 0% by weight to 50% by weight, preferably 0% by weight to 30% by weight, more preferably 0% by weight to 10% by weight, and still more preferably 0%. 0.01 wt% to 10 wt%, particularly preferably 0.01 wt% to 7 wt%. The blending ratio is a blending ratio when the blending ratio of the monomer (I) + the blending ratio derived from the monomer (II) + the blending ratio of the monomer (III) = 100% by weight.

  Hereinafter, first, the monomer (I) will be described. The monomer (II) and the monomer (III) will be described later in the description of the monomer (IV) constituting the polycarboxylic acid copolymer or the salt (B) thereof.

（式中、Ｒ¹は、炭素原子数２〜５のアルケニル基を表す。Ａ¹Ｏは、同一若しくは異なって、炭素原子数２〜１８のオキシアルキレン基を表す。ｎ１は、オキシアルキレン基の平均付加モル数であり、１〜８０の数を表す。Ｒ²は、水素原子または炭素原子数１〜３０の炭化水素基を表す。） Monomer (I) is a polyalkylene glycol monoalkenyl ether represented by the following general formula (1).

(In the formula, R ¹ represents an alkenyl group having 2 to 5 carbon atoms. A ¹ O is the same or different and represents an oxyalkylene group having 2 to 18 carbon atoms. N1 represents an oxyalkylene group. (The average number of moles added represents a number of 1 to 80. R ² represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms.)

R ¹ in the general formula (1) represents an alkenyl group having 2 to 5 carbon atoms. The number of carbon atoms of the alkenyl group is preferably 3-5. Specific examples of R ¹ include an allyl group, a methallyl group, a residue of 3-methyl-3-buten-1-ol, and the like, but are not limited thereto.

A ¹ O in the general formula (1) is the same or different and represents an oxyalkylene group having 2 to 18 carbon atoms. Examples of the oxyalkylene group include oxyethylene group (ethylene glycol), oxypropylene group (propylene glycol), oxybutylene group (butylene glycol), oxyethylene group (ethylene glycol), oxypropylene group (propylene glycol) ) Is preferred.

The above “same or different” means that when A ¹ O is contained in the general formula (1) (when n1 is 2 or more), each A ¹ O may be the same oxyalkylene group. Meaning that it may be different (two or more) oxyalkylene groups. The case where a plurality of A ¹ O are contained in the general formula (1) is selected from the group consisting of oxyethylene group (ethylene glycol), oxypropylene group (propylene glycol) and oxybutylene group (butylene glycol) 2 Examples include a mixture of the above oxyalkylene groups, a mixture of oxyethylene groups (ethylene glycol) and oxypropylene groups (propylene glycol), or oxyethylene groups (ethylene glycol) and oxybutylene groups (butylene glycol). Is preferable, and an aspect in which an oxyethylene group (ethylene glycol) and an oxypropylene group (propylene glycol) are mixed is more preferable. In an embodiment in which different oxyalkylene groups are mixed, the addition of two or more oxyalkylene groups may be a block addition or a random addition.

  N1 in General formula (1) is the average addition mole number of an oxyalkylene group, and represents the number of 1-80. n1 is preferably 1 to 40, more preferably 5 to 30, further preferably 7 to 30, and most preferably 7 to 25. The average number of moles added means the average number of moles of alkylene glycol units added to 1 mole of monomer.

R ² in the general formula (1) represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms. When the number of carbon atoms increases, the cement dispersibility of the cement admixture may not be sufficiently exhibited. Therefore, R ² is preferably a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. A hydrocarbon group of 1 to 5 is more preferable, and hydrogen or a methyl group is most preferable.

  As a manufacturing method of monomer (I), the method of adding 1-80 mol of alkylene oxides to unsaturated alcohols, such as allyl alcohol, methallyl alcohol, 3-methyl-3-buten-1-ol, is mentioned, for example. It is done. As the monomer (I), for example, (poly) ethylene glycol allyl ether, (poly) ethylene glycol methallyl ether, (poly) ethylene glycol 3-methyl-3-butenyl ether, (poly) ethylene (poly) propylene Glycol allyl ether, (poly) ethylene (poly) propylene glycol methallyl ether, (poly) ethylene (poly) propylene glycol 3-methyl-3-butenyl ether, (poly) ethylene (poly) butylene glycol allyl ether, (poly) Ethylene (poly) butylene glycol methallyl ether, (poly) ethylene (poly) butylene glycol 3-methyl-3-butenyl ether, methoxy (poly) ethylene glycol allyl ether, methoxy (poly) ethylene glycol methallyl ether , Methoxy (poly) ethylene glycol 3-methyl-3-butenyl ether, methoxy (poly) ethylene (poly) propylene glycol allyl ether, methoxy (poly) ethylene (poly) propylene glycol methallyl ether, methoxy (poly) ethylene ( Poly) propylene glycol 3-methyl-3-butenyl ether, methoxy (poly) ethylene (poly) butylene glycol allyl ether, methoxy (poly) ethylene (poly) butylene glycol methallyl ether, methoxy (poly) ethylene (poly) butylene glycol 3-methyl-3-butenyl ether is mentioned. As the monomer (I), one or more of these can be used, but it is preferable to use (poly) ethylene glycol (meth) allyl ether from the balance of hydrophilicity and hydrophobicity. Also in the specific example of the monomer (I), the average added mole number of the oxyalkylene group (polyalkylene glycol) is preferably 5 to 30, more preferably 7 to 30, and 7 to 25. More preferably it is. In the present specification, “(poly)” means that the number of substituents immediately after that is one or two or more.

  The polycarboxylic acid copolymer or its salt (B) is composed of 5 to 95% by weight of the monomer (IV) represented by the general formula (2), 1 to 1 of the unsaturated monocarboxylic acid monomer (II) It is obtained by copolymerizing 50% by weight of a monomer containing 0 to 10% by weight of monomer (V) copolymerizable with monomer (II) and / or (IV). The copolymer essentially comprises a structural unit derived from the monomer (IV), a structural unit derived from the unsaturated monocarboxylic acid monomer (II), and a structural unit derived from the monomer (IV). It is a copolymer which has as a structural unit.

  The blending ratio of each monomer when obtaining the polycarboxylic acid copolymer or salt (B) is as follows. The blending ratio of the monomer (IV) is 5% to 95% by weight, preferably 20% to 95% by weight, more preferably 30% to 95% by weight, and still more preferably 40% by weight. ˜95 wt%, even more preferably 50 wt% to 95 wt%, particularly preferably 60 wt% to 95 wt%, and most preferably 70 wt% to 95 wt%. The blending ratio of the monomer (II) is 1% to 50% by weight, preferably 2% to 40% by weight, more preferably 5% to 30% by weight, and still more preferably 7%. % By weight to 25% by weight. The blending ratio of the monomer (V) is 0% by weight to 50% by weight, preferably 0% by weight to 30% by weight, more preferably 0% by weight to 10% by weight, and still more preferably 0.01%. % By weight to 10% by weight, particularly preferably 0.01% by weight to 7% by weight. The blending ratio is a blending ratio when the blending ratio of the monomer (IV) + the blending ratio derived from the monomer (II) + the blending ratio of the monomer (V) = 100 wt%.

（式中、Ｒ³、Ｒ⁴およびＲ⁵は、それぞれ独立に水素原子または炭素原子数１〜３のアルキル基を表す。ｍは、０〜２の数を表す。Ａ²Ｏは、同一若しくは異なって、炭素原子数２〜１８のオキシアルキレン基を表す。ｎ２は、オキシアルキレン基の平均付加モル数であり、１〜８０の数を表す。Ｘは、水素原子または炭素原子数１〜３０の炭化水素基を表す。） Monomer (IV) is represented by the structure represented by the following general formula (2).

(In the formula, R ³ , R ⁴ and R ⁵ each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. M represents a number of 0 to ^2. A ² O is the same or Differently, it represents an oxyalkylene group having 2 to 18 carbon atoms, n2 is an average addition mole number of the oxyalkylene group, and represents a number of 1 to 80. X is a hydrogen atom or 1 to 30 carbon atoms. Represents a hydrocarbon group of

R ³ , R ⁴ and R ⁵ in the general formula (2) each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

A ² O in the general formula (2) is the same or different and represents an oxyalkylene group having 2 to 18 carbon atoms. Examples of the oxyalkylene group include oxyethylene group (ethylene glycol), oxypropylene group (propylene glycol), oxybutylene group (butylene glycol), oxyethylene group (ethylene glycol), oxypropylene group (propylene glycol) ) Is preferred.

The above “same or different” means that when A ² O is contained in the general formula (2) (when n2 is 2 or more), each A ² O may be the same oxyalkylene group. Meaning that it may be different (two or more) oxyalkylene groups. In the case where a plurality of A ² O are contained in the general formula (2), ² is selected from the group consisting of oxyethylene group (ethylene glycol), oxypropylene group (propylene glycol) and oxybutylene group (butylene glycol). Examples include a mixture of the above oxyalkylene groups, a mixture of oxyethylene groups (ethylene glycol) and oxypropylene groups (propylene glycol), or oxyethylene groups (ethylene glycol) and oxybutylene groups (butylene glycol). Is preferable, and an oxyethylene group (ethylene glycol) and an oxypropylene group (propylene glycol) are more preferable. In an embodiment in which different oxyalkylene groups are mixed, the addition of two or more oxyalkylene groups may be a block addition or a random addition.

  N2 in General formula (2) is the average addition mole number of an oxyalkylene group, and represents the number of 1-80. n2 is preferably 1 to 40, more preferably 5 to 30, still more preferably 7 to 30, and most preferably 10 to 25. The average number of moles added means the average number of moles of alkylene glycol units added to 1 mole of monomer.

  X in the general formula (2) represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms. If the number of carbon atoms increases, the cement dispersibility of the cement admixture may not be sufficiently exhibited, so X is preferably hydrogen or a hydrocarbon group having 1 to 10 carbon atoms, 5 is more preferable, and hydrogen or a methyl group is most preferable.

  Examples of the monomer (IV) include an unsaturated monocarboxylic acid such as (meth) acrylate (hereinafter, “(meth) acrylate” means “acrylate or methacrylate”), and (poly) ethylene glycol. , (Poly) ethylene (poly) propylene glycol, (poly) ethylene (poly) butylene glycol, methoxy (poly) ethylene glycol, methoxy (poly) ethylene (poly) propylene glycol, methoxy (poly) ethylene (poly) butylene glycol, etc. Of (poly) alkylene glycols. Specifically, for example, (poly) ethylene glycol (meth) acrylate, (poly) ethylene (poly) propylene glycol (meth) acrylate, (poly) ethylene (poly) butylene glycol (meth) acrylate, methoxy (poly) ethylene Examples include (poly) alkylene glycol (meth) acrylates such as glycol (meth) acrylate, methoxy (poly) ethylene (poly) propylene glycol (meth) acrylate, and methoxy (poly) ethylene (poly) butylene glycol (meth) acrylate. . As the monomer (IV), one or more of these can be used in combination, but (poly) alkylene glycol (meth) acrylate is preferably used, and methoxy (poly) ethylene glycol (meth) It is more preferable to use acrylate. The average number of added moles of (poly) alkylene glycol is preferably 5 to 30, preferably 7 to 30, and most preferably 10 to 25.

  In the present invention, the unsaturated monocarboxylic acid monomer (II) constitutes each of the polycarboxylic acid copolymer or its salts (A) and (B). Specific examples of the unsaturated monocarboxylic acid monomer (II) include carboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid, and salts thereof (for example, monovalent metal salts and divalent metals). Salt, ammonium salt, organic amine salt). One or more of these can be used as the unsaturated monocarboxylic acid monomer (II). Among them, acrylic acid or a salt thereof, methacrylic acid or a salt thereof is preferable. Unsaturated monocarboxylic acid monomer (II) in polycarboxylic acid copolymer or salt (A) thereof, and unsaturated monocarboxylic acid monomer in polycarboxylic acid copolymer or salt (B) thereof The body (II) may be the same or different.

  The monomer (III) is not particularly limited as long as it is a monomer copolymerizable with the monomer (I) and / or (II). The monomer (V) is not particularly limited as long as it is a monomer copolymerizable with the monomer (IV) and / or (II). Monomer (III) does not include monomer (I) and monomer (IV). Further, the monomer (V) does not include the monomer (IV) and the monomer (I).

  Examples of the monomer (III) and the monomer (V) include the following, and one or more of these can be used. Monomer (III) and monomer (V) may be the same or different.

Half esters and diesters of unsaturated dicarboxylic acids such as maleic acid, maleic anhydride, fumaric acid, itaconic acid, citraconic acid and alcohols having 1 to 30 carbon atoms;
Half amides and diamides of the above unsaturated dicarboxylic acids and amines having 1 to 30 carbon atoms;
Half esters and diesters of an alkyl (poly) alkylene glycol obtained by adding 1 to 500 moles of an alkylene oxide having 2 to 18 carbon atoms to the alcohol or amine and the unsaturated dicarboxylic acid;
Half esters and diesters of the above unsaturated dicarboxylic acids and glycols having 2 to 18 carbon atoms or polyalkylene glycols having 2 to 500 addition moles of these glycols;
Half amides of maleamic acid and glycols having 2 to 18 carbon atoms or polyalkylene glycols having 2 to 500 addition moles of these glycols.

(Poly) alkylene glycols such as triethylene glycol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, (poly) ethylene glycol (poly) propylene glycol di (meth) acrylate, etc. Di (meth) acrylates;
Polyfunctional (meth) acrylates such as hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane di (meth) acrylate;
(Poly) alkylene glycol dimaleates such as triethylene glycol dimaleate and polyethylene glycol dimaleate;
Vinyl sulfonate, (meth) allyl sulfonate, 2- (meth) acryloxyethyl sulfonate, 3- (meth) acryloxypropyl sulfonate, 3- (meth) acryloxy-2-hydroxypropyl sulfonate, 3- (meth) acryloxy-2 -Hydroxypropylsulfophenyl ether, 3- (meth) acryloxy-2-hydroxypropyloxysulfobenzoate, 4- (meth) acryloxybutylsulfonate, (meth) acrylamidomethylsulfonic acid, (meth) acrylamidoethylsulfonic acid, 2- Unsaturated sulfonic acids such as methylpropanesulfonic acid (meth) acrylamide and styrenesulfonic acid, and monovalent metal salts, divalent metal salts, ammonium salts and organic amine salts thereof;
Amides of unsaturated monocarboxylic acids such as methyl (meth) acrylamide and amines having 1 to 30 carbon atoms;
Vinyl aromatics such as styrene, α-methylstyrene, vinyltoluene, p-methylstyrene;
(Meth) allylphenol, (meth) allylbisphenol (compound in which one or more carbon atoms contained in bisphenol (eg, bisphenol A, bisphenol E, bisphenol AD, 4,4′-dihydroxydiphenylsulfone) are substituted with allyl) Kind;
Alkanediol mono (meth) acrylates such as 1,4-butanediol mono (meth) acrylate, 1,5-pentanediol mono (meth) acrylate, 1,6-hexanediol mono (meth) acrylate;
Dienes such as butadiene, isoprene, 2-methyl-1,3-butadiene, and 2-chloro-1,3-butadiene.

Unsaturated amides such as (meth) acrylamide, (meth) acrylic alkylamide, N-methylol (meth) acrylamide, N, N-dimethyl (meth) acrylamide;
Unsaturated cyanides such as (meth) acrylonitrile, α-chloroacrylonitrile;
Unsaturated esters such as vinyl acetate and vinyl propionate; aminoethyl (meth) acrylate, methylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, (meth ) Unsaturated amines such as dibutylaminoethyl acrylate and vinylpyridine;
Divinyl aromatics such as divinylbenzene; cyanurates such as triallyl cyanurate;
Allyls such as (meth) allyl alcohol and glycidyl (meth) allyl ether;
Vinyl ethers or allyl ethers such as methoxypolyethylene glycol monovinyl ether, polyethylene glycol monovinyl ether, methoxypolyethylene glycol mono (meth) allyl ether, polyethylene glycol mono (meth) allyl ether;
Polydimethylsiloxanepropylaminomaleamic acid, polydimethylsiloxaneaminopropylaminomaleamic acid, polydimethylsiloxane-bis- (propylaminomaleamic acid), polydimethylsiloxane-bis- (dipropylaminomaleamic acid), polydimethyl Siloxane- (1-propyl-3-acrylate), polydimethylsiloxane- (1-propyl-3-methacrylate), polydimethylsiloxane-bis- (1-propyl-3-acrylate), polydimethylsiloxane-bis- (1 Siloxane derivatives such as -propyl-3-methacrylate).

  Of these, aromatic allyls are preferably used, and (meth) allylphenol is more preferable. (Meth) allylphenol preferably has two or more phenol groups. The (meth) allylphenol preferably has two or more allyl groups. As (meth) allylphenol, those having two or more phenol groups and two or more allyl groups are preferable, and compounds in which 4,4′-dihydroxydiphenylsulfone is allyl-substituted are more preferable, and 4,4′-dihydroxydiphenylsulfone More preferred are compounds in which the 3 and 3 ′ positions are allyl substituted.

  Monomers essential for obtaining the polycarboxylic acid copolymer or its salt (A) are monomer (I), monomer (II) and monomer (III). In addition, monomers other than these may be used. The polycarboxylic acid copolymer or salt (A) thereof is different from the polycarboxylic acid copolymer or salt (B) thereof. That is, the polycarboxylic acid copolymer or its salt (A) does not substantially contain a structural unit derived from the monomer (IV). The term “substantially free” in the present invention means that it is not contained at all or is contained in a very small amount, preferably not contained at all.

  Monomers essential for obtaining the polycarboxylic acid copolymer or salt (B) thereof are monomer (IV), monomer (II) and monomer (V). In addition, monomers other than these may be used. The polycarboxylic acid copolymer or salt (B) thereof is different from the polycarboxylic acid copolymer or salt (A) thereof. That is, the polycarboxylic acid copolymer or its salt (B) does not contain a structural unit derived from the monomer (I).

  In the present invention, the polycarboxylic acid copolymer or each of its salts (A) and (B) can be produced by copolymerizing each predetermined monomer by a known method. . Examples of the method include polymerization methods such as polymerization in a solvent and bulk polymerization.

  Examples of the solvent used in the polymerization in the solvent include water; lower alcohols such as methyl alcohol, ethyl alcohol and isopropyl alcohol; aromatic hydrocarbons such as benzene, toluene and xylene; fats such as cyclohexane and n-hexane. Group hydrocarbons; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone. From the viewpoint of solubility of the raw material monomer and the resulting copolymer, it is preferable to use one or more selected from the group consisting of water and lower alcohols, and among these, water is more preferable.

  When copolymerization is performed in a solvent, each monomer and a polymerization initiator may be continuously dropped into each reaction vessel, or a mixture of each monomer and a polymerization initiator are dropped continuously into each reaction vessel. Also good. Alternatively, a solvent may be charged into the reaction vessel, and a mixture of the monomer and the solvent and a polymerization initiator solution may be continuously dropped into the reaction vessel, or a part or all of the monomer may be charged into the reaction vessel and polymerized. The initiator may be continuously dropped.

  The polymerization initiator that can be used for copolymerization is, for example, persulfates such as ammonium persulfate, sodium persulfate, and potassium persulfate; and water-soluble such as t-butyl hydroperoxide. An organic peroxide is mentioned. In this case, an accelerator such as sodium hydrogen sulfite and a mol salt can be used in combination. When copolymerization is performed in a solvent such as a lower alcohol, aromatic monohydrocarbon, aliphatic hydrocarbon, ester or ketone, for example, a peroxide such as benzoyl peroxide or lauryl peroxide; Hydroperoxides such as oxides; aromatic azo compounds such as azobisisobutyronitrile can be used as the polymerization initiator. In this case, an accelerator such as an amine compound can be used in combination. Furthermore, when copolymerization is carried out in a water-lower alcohol mixed solvent, it can be used by appropriately selecting from the aforementioned polymerization initiator or a combination of a polymerization initiator and an accelerator. Although superposition | polymerization temperature changes suitably with the solvent to be used and a polymerization initiator, it is normally performed in 50-120 degreeC.

  In the copolymerization, the molecular weight can be adjusted using a chain transfer agent as required. Examples of the chain transfer agent used include mercaptoethanol, thioglycerol, thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thiomalic acid, octyl thioglycolate, and 2-mercaptoethanesulfonic acid. Known thiol compounds: phosphorous acid, hypophosphorous acid, and salts thereof (sodium hypophosphite, potassium hypophosphite, etc.), sulfurous acid, hydrogen sulfite, dithionite, metabisulfite, and Lower oxides of salts thereof (sodium sulfite, potassium sulfite, sodium hydrogen sulfite, potassium hydrogen sulfite, sodium dithionite, potassium dithionite, sodium metabisulfite, potassium metabisulfite, etc.) and salts thereof; Can be mentioned. These may be used alone or in combination of two or more. Furthermore, in order to adjust the molecular weight of the polycarboxylic acid copolymer or its salts (A) and (B), a monomer having a higher chain transfer property may be used as a monomer for obtaining each. It is valid. Examples of the monomer (VI) having a high chain transfer property include (meth) allylsulfonic acid (salt) monomers. The blending ratio of the monomer (VI) is usually 20% by weight or less and 10% by weight or less in any of the polycarboxylic acid copolymer or its salts (A) and (B). preferable. In addition, the above-mentioned blending ratio is (A) when the blending ratio of the monomer (I) + the blending ratio derived from the monomer (II) + the blending ratio of the monomer (III) = 100% by weight. It is a blending ratio, and (B) is a blending ratio when the blending ratio of the monomer (IV) + the blending ratio derived from the monomer (II) + the blending ratio of the monomer (V) = 100% by weight. It is.

When copolymerization is carried out in an aqueous solvent when obtaining a copolymer, the pH during polymerization usually becomes strongly acidic due to the influence of a monomer having an unsaturated bond, but this may be adjusted to an appropriate pH. . If it is necessary to adjust the pH during polymerization, adjust the pH using an acidic substance such as phosphoric acid, sulfuric acid, nitric acid, alkylphosphoric acid, alkylsulfuric acid, alkylsulfonic acid, or (alkyl) benzenesulfonic acid. Can do. Among these acidic substances, it is preferable to use phosphoric acid because it has a pH buffering action. However, in order to eliminate the instability of the ester bond of the ester monomer, it is preferable to perform the polymerization at pH 2-7. Moreover, although there is no limitation in particular in the alkaline substance which can be used for adjustment of pH, alkaline substances, such as NaOH and Ca (OH) _2, are common. The pH adjustment may be performed on the monomer before polymerization or may be performed on the copolymer solution after polymerization. In addition, these may be subjected to polymerization by adding a part of an alkaline substance before polymerization, and then the pH of the copolymer may be further adjusted.

The copolymer thus obtained from a predetermined monomer can be used as it is as the components (A) and (B) of the cement admixture of the present invention as it is, but these copolymers can be used as needed. Alternatively or in addition to these copolymers, salts of the copolymer may be used as the components (A) and (B) of the cement admixture. Examples of the salt of the copolymer include a salt obtained by neutralizing the copolymer with an alkaline substance. When the cement admixture of the present invention contains the salt as components (A) and (B), the cement admixture is less susceptible to inhibition of adsorption to the cement and exhibits superior cement dispersibility. Such an alkaline substance is not particularly limited, but usually, inorganic substances such as hydroxides, chlorides and carbon salts of monovalent metals and divalent metals such as NaOH and Ca (OH) ₂ ; ammonia; organic Preferred examples include amines.

  The weight average molecular weight of the polycarboxylic acid copolymer or salt (A) is preferably 5,000 to 50,000. When the weight average molecular weight is less than 5,000, the cement dispersibility of the cement admixture is not sufficiently exhibited, and the water reduction rate exceeding the AE water reducing agent such as lignin sulfonic acid type or oxycarboxylic acid type cannot be obtained, and fluidity There is a possibility that the intended effect as a cement admixture may not be sufficiently exhibited, such as improvement of workability and operability. On the other hand, if the weight average molecular weight exceeds 50,000, the cohesive action is exhibited and the workability may be reduced. Furthermore, when the cement admixture of the present invention is used in combination with another cement admixture, the amount of adsorption of the other cement admixture to the cement particles per unit area becomes high, and the cement admixture of the present invention is subject to adsorption inhibition. The required cement dispersibility may not be obtained. The weight average molecular weight of the polycarboxylic acid copolymer or its salt (A) is more preferably 7,000 to 35,000, still more preferably 8,000 to 30,000.

  The molecular weight distribution (Mw / Mn) of the polycarboxylic acid copolymer or salt (A) is preferably in the range of 1.2 to 3.0. Mw / Mn is preferably in the range of 1.3 to 2.0, more preferably 1.5 to 2.0. When Mw / Mn is less than 1.2, the fluidity of the concrete is insufficient, and good slump retention may not be obtained. If it exceeds 3.0, the fluidity may be insufficient.

  The weight average molecular weight of the polycarboxylic acid copolymer or salt (B) is preferably in the range of 5,000 to 60,000. By being in this range, good cement dispersibility is obtained, and concrete with reduced viscosity is obtained. Furthermore, it is more preferably in the range of 8,000 to 60,000, and still more preferably in the range of 10,000 to 56,000.

  The molecular weight distribution (Mw / Mn) of the polycarboxylic acid copolymer or salt (B) is preferably in the range of 1.2 to 3.0. A range of 1.3 to 3.0 is more preferable, and a range of 1.4 to 2.7 is even more preferable. When Mw / Mn is less than 1.2, the fluidity of the concrete is insufficient, and good slump retention may not be obtained. If it exceeds 3.0, the fluidity may be insufficient.

  In addition, the weight average molecular weight in this invention can be measured by the well-known method converted into polyethyleneglycol by gel permeation chromatography (GPC).

Although there is no limitation in particular as measurement conditions of GPC, the following conditions can be mentioned as an example.
Measuring device; column used by Tosoh; Shodex Column OH-pak SB-806HQ, SB-804HQ, SB-802.5HQ
Eluent: 0.05 mM sodium nitrate / acetonitrile 8/2 (v / v)
Standard material: Polyethylene glycol (Tosoh, GL Science)
Detector: differential refractometer (manufactured by Tosoh)
Calibration curve; polyethylene glycol standard

  In the present invention, the polycarboxylic acid copolymer or the salts (A) and (B) thereof may be one or more compounds. In addition, each of the components (A) and (B) may be used alone or as a mixture of the components (A) and (B), and may or may not have the function of a cement dispersant. Moreover, if there exists a commercially available dispersing agent containing these copolymers or its salt, a polycarboxylic acid type | system | group copolymer or its salt (A) and its (B) will respectively be (A) and (B) component as it is May be used as

  The sulfonic acid compound (C) preferably has a sulfonic acid group in the molecule from the viewpoint of expressing the cement dispersibility of the cement admixture. By having a sulfonic acid group in the molecule, electrostatic repulsion occurs between the sulfonic acid group and the cement, and higher cement dispersibility is exhibited.

  In the present invention, as the sulfonic acid compound (C), a known compound can be used and is not limited, but it is preferable to use a compound having an aromatic group in the molecule. In other words, in combination with the above points, the sulfonic acid compound (C) preferably has a sulfonic acid group and an aromatic group in the molecule. Specific examples of the sulfonic acid compound (C) include polyalkylaryl sulfonates such as naphthalene sulfonic acid formaldehyde condensate, methyl naphthalene sulfonic acid formaldehyde condensate, anthracene sulfonic acid formaldehyde condensate; melamine sulfonic acid Melamine formalin sulfonates such as formaldehyde condensates; aromatic amino sulfonates such as aminoaryl sulfonic acid-phenol-formaldehyde condensates; lignin sulfonates such as lignin sulfonates and modified lignin sulfonates; polystyrene sulfones Acid salt; and the like. Of these, lignin sulfonate is preferred. As the sulfonic acid compound (C), a commercially available cement dispersant (eg, lignin sulfonic acid dispersant) containing a sulfonic acid compound may be used.

  When the cement dispersant of the present invention is used for concrete having a large water / cement ratio, a lignin sulfonate dispersant is preferably used as the sulfonic acid compound (C). On the other hand, when the cement admixture of the present invention is used for concrete having a medium water / cement ratio that is required to exhibit higher water reduction, the polysulfonic acid compound (C) may be a polyalkyl. Aryl sulfonate compounds, melamine formalin resin sulfonate compounds, aromatic amino sulfonate compounds, polystyrene sulfonate compounds and the like are preferably used.

  The oxycarboxylic acid, sugar, or salt (D) thereof may be one or a combination of two or more selected from the group consisting of oxycarboxylic acids, saccharides, and salts thereof. Examples of oxycarboxylic acids include gluconic acid, glucoheptonic acid, arabonic acid, malic acid, and citric acid. Examples of the salts of oxycarboxylic acids include inorganic or organic salts such as sodium, potassium, calcium, magnesium, ammonium, triethanolamine, and the like of the compounds mentioned as specific examples of the oxycarboxylic acids.

  Examples of the saccharide include monosaccharides such as glucose, fructose, galactose, saccharose, xylose, apiose, ribose, and isomerized sugar, oligosaccharides such as disaccharide and trisaccharide, oligosaccharide such as dextrin, and dextran. And the like. Examples of sugars include molasses containing these sugars and sugar alcohols such as sorbitol. Examples of the saccharide salt include inorganic or organic salts such as sodium, potassium, calcium, magnesium, ammonium and triethanolamine of the compounds mentioned as specific examples of the saccharide.

  As the oxycarboxylic acid, sugar or salt (D) thereof, oxycarboxylic acids are preferably used, and gluconic acid or a salt thereof is particularly preferably used. In addition, oxycarboxylic acid, saccharide | sugar, or these salts (D) may be used individually by 1 type, and may use 2 or more types together. In addition, as oxycarboxylic acid, sugar, or salts thereof (D), a commercially available cement dispersant (eg, sodium gluconate cement dispersant) containing oxycarboxylic acid, sugar, or salt thereof may be used. .

  In the present invention, the content ratios of the polycarboxylic acid copolymer or salts (A) and (B) thereof, the sulfonic acid compound (C), and the oxycarboxylic acid, sugar or salt thereof (D) are as follows: The solid content is (A) :( B) :( C) :( D) = 1 to 90% by weight: 1 to 90% by weight: 1 to 90% by weight: 1 to 90% by weight. From the point of expression of the dispersibility (fluidity) of the cement admixture, (A) :( B) :( C) :( D) = 5-90 wt%: 10-90 wt%: 1-70 % By weight: preferably 1 to 50% by weight, (A): (B): (C): (D) = 20-90% by weight: 10-80% by weight: 3-80% by weight: 1 More preferably, it is 60% by weight. In addition, all said content rate is a numerical value when (A) + (B) + (C) + (D) = 100 weight%.

  The cement admixture of the present invention comprises polycarboxylic acid copolymers or salts thereof (A) and (B), sulfonic acid compounds (C) and oxycarboxylic acids, sugars or salts thereof (D) as essential components. Prepared.

  The cement admixture of the present invention may further contain other components as necessary. Examples of other components include (poly) alkylene glycol alkenyl ether monomers (E) and water-soluble polyalkylene glycols (F) in which both terminal groups are hydrogen atoms.

  When the cement admixture of the present invention contains the (poly) alkylene glycol alkenyl ether monomer (E), the resulting cement admixture can reduce the viscosity of the cement composition and improve workability. It is preferable in that it can be performed.

  The content ratio of the (poly) alkylene glycol alkenyl ether monomer (E) in the cement admixture of the present invention is 90% by weight or less based on the polycarboxylic acid copolymer or salt (A) thereof. More preferably, it is 80% by weight or less, more preferably 60% by weight or less, particularly preferably 50% by weight or less, and particularly preferably 40% by weight or less. If it exceeds 90% by weight, the dispersibility of the cement may not be sufficiently exhibited, which is not preferable. Moreover, in order to obtain the workability improvement effect by the (poly) alkylene glycol alkenyl ether monomer (E), the lower limit is usually 1% by weight or more.

  Specific examples and preferred examples of the (poly) alkylene glycol alkenyl ether monomer (E) are the same as those described for the monomer (I). The (poly) alkylene glycol alkenyl ether monomer (E) may be the same as or different from the monomer (I). Furthermore, as the (poly) alkylene glycol alkenyl ether monomer monomer (E), one or more (poly) alkylene glycol alkenyl ether monomers may be used.

  The (poly) alkylene glycol alkenyl ether monomer (E) may be blended separately from the polycarboxylic acid copolymer or salt (A) thereof, and is produced, for example, as follows. You may mix | blend as a composition (cement dispersing agent) with a polycarboxylic acid-type copolymer or its salt (A). The monomer (I) used as a raw material when the polycarboxylic acid copolymer or its salt (A) is produced remains in the polycarboxylic acid copolymer or its salt (A). By stopping the polymerization reaction at the time, a composition containing the (poly) alkylene glycol alkenyl ether monomer (E) and the polycarboxylic acid copolymer or salt (A) thereof can be obtained. The point at which the polymerization reaction is stopped can be determined according to the blending ratio of the (poly) alkylene glycol alkenyl ether monomer to the polycarboxylic acid copolymer or salt (A) thereof. That is, the residual amount of the (poly) alkylene glycol alkenyl ether monomer (E) with respect to the polycarboxylic acid copolymer or salt (A) is preferably 80% by weight or less, more preferably 60% by weight or less. More preferably, the polymerization reaction is stopped at a point of 50% by weight or less, particularly preferably 40% by weight or less. The polymerization reaction is stopped when the lower limit of the residual amount is usually 1% by weight or more.

  As described above, the cement admixture of the present invention may further contain a water-soluble polyalkylene glycol (F) in which both terminal groups are hydrogen atoms. That both terminal groups are hydrogen atoms means that the terminal of the main chain is a hydrogen atom, that is, the terminal of the main chain is not substituted with a substituent other than a hydrogen atom. Water-soluble means soluble in water. The blending ratio of the water-soluble polyalkylene glycol (F) in which both terminal groups are hydrogen atoms is usually less than 1% by weight with respect to the polycarboxylic acid copolymer or salt (A) thereof. Although the minimum of this mixture ratio is not specifically limited, Usually, it is 0.001 weight% or more with respect to a polycarboxylic acid type copolymer or its salt (A). The water-soluble polyalkylene glycol (F) in which both terminal groups are hydrogen atoms may be blended separately from the polycarboxylic acid copolymer or salt (A) thereof. On the other hand, when producing the monomer (I) which is a raw material of the polycarboxylic acid copolymer or its salt (A), a water-soluble polyalkylene glycol in which both terminal groups are hydrogen atoms is produced as a by-product. This may be used. The weight average molecular weight of the water-soluble polyalkylene glycol (F) in which both terminal groups are hydrogen atoms is preferably 300 to 2,000, and more preferably 300 to 1,000.

  Specific examples of the water-soluble polyalkylene glycol (F) in which both terminal groups are hydrogen atoms include polyethylene glycol, polypropylene glycol, polyethylene polypropylene glycol, polyethylene polybutylene glycol and the like, and polyethylene glycol is preferred. The water-soluble polyalkylene glycol (F) whose both terminal groups are hydrogen atoms can be used alone or in combination of two or more.

  The cement admixture of the present invention is an AE agent, a water reducing agent, an AE water reducing agent, a high performance water reducing agent, a high performance AE water reducing agent, a flow agent, a retarder, a quick setting agent, and a dust reduction as long as the desired effect is not impaired. Agent, underwater non-separable admixture, separation reducing agent, pumping aid, antifreeze / cold resistant agent, alkali aggregate reaction inhibitor, neutralization inhibitor, shrinkage reducing agent, heat of hydration inhibitor, foaming agent, It is possible to use a foaming agent, a quick-release admixture, and the like in combination.

  The cement admixture of the present invention can be used in the form of an aqueous solution or in the form of powder after drying. The time when the cement admixture is added to other components constituting the cement composition or hydraulic materials other than the cement composition may be during use of the cement composition. In addition, the cement admixture of the present invention in a powdered form is previously mixed with components other than water constituting the cement composition, such as cement powder and dry mortar, and plastering, floor finishing, grout, etc. In this case, it can also be used as a premix product to which water is added.

  The cement admixture of the present invention can be added to a hydraulic material such as cement and used as a cement composition such as cement paste, mortar, concrete, or plaster.

  The cement composition of this invention should just contain a cement admixture, and the hydraulic material to combine is not specifically limited. Examples of the hydraulic material include cement, gypsum (semihydrate gypsum, dihydrate gypsum, etc.), and dolomite. The most common hydraulic material is cement.

  The cement is not particularly limited. For example, Portland cement (ordinary, early strength, very early strength, moderate heat, sulfate-resistant and low alkali type of each), various mixed cements (blast furnace cement, silica cement, fly ash cement), white Portland cement, alumina cement, Super fast cement (1 clinker fast cement, 2 clinker fast cement, magnesium phosphate cement), grout cement, oil well cement, low exothermic cement (low exothermic blast furnace cement, fly ash mixed low exothermic blast furnace cement, belite High-content cement), ultra-high-strength cement, cement-based solidified material, eco-cement (cement produced using at least one of municipal waste incineration ash and sewage sludge incineration ash). Blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica fume, silica powder, limestone powder and other fine powder, gypsum and the like may be added to the cement.

  Moreover, the cement composition may contain the aggregate. The aggregate may be either a fine aggregate or a coarse aggregate. Examples of aggregates include sand, gravel, crushed stone; granulated slag; recycled aggregate, etc .; siliceous, clay, zircon, high alumina, silicon carbide, graphite, chrome, chromic, magnesia Fireproof aggregates such as

  There is no particular limitation on the blending ratio of the cement admixture in the cement composition. For example, when the cement composition is mortar, concrete or the like, a cement admixture (polycarboxylic acid copolymers or salts thereof (A) and (B), sulfonic acid compounds (C) and oxycarboxylic acids) , Sugar or their salts (D) (total weight) is added in an amount of 0.01 to 5.0% by weight, preferably 0.02 to 2.0% by weight, based on the total weight of the cement. %, More preferably 0.05 to 1.0% by weight. By setting this addition amount, the resulting cement composition has various preferable effects such as a reduction of 30 unit water amount, an increase in strength, and an improvement in durability. If the blending ratio is less than 0.01% by weight, the resulting cement composition may not be sufficient in terms of performance, and conversely, even if a large amount exceeding 5.0% by weight is used, the effect is substantially reduced. There is a risk that it will hit a peak and be disadvantageous in terms of economy.

  The cement composition is effective as, for example, ready-mixed concrete, concrete for concrete secondary products (precast concrete), concrete for centrifugal molding, concrete for vibration compaction, steam-cured concrete, shotcrete, and the like. Furthermore, 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, self-leveling material It is also effective as mortar or concrete that requires high fluidity such as.

  The cement admixture of the present invention can be used as a cement dispersant as it is. Still other cement dispersants, water-soluble polymers, polymer emulsions, air entrainers, cement wetting agents, swelling agents, waterproofing agents, retarders, thickeners, flocculants, drying shrinkage reducing agents, strength enhancers, effects It can also be used in combination with known additives for concrete such as accelerators, antifoaming agents, AE agents, and other surfactants. These may be used alone or in combination of two or more.

  The present invention will be described more specifically with reference to the following examples, but the present invention is not limited thereto. In the examples, unless otherwise indicated, “%” means “% by weight” and “parts” means “parts by weight”.

<Production Example 1>
[Production of Polycarboxylic Acid Copolymer (M-1) and its Salt (A-1)]
148 parts of water, 347 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added 10) in a glass reaction vessel equipped with a thermometer, a stirring device, a reflux device, a nitrogen introduction tube and a dropping device, and 4,4 ′ -1 part of a compound in which the 3 and 3 'positions of dihydroxydiphenylsulfone were allyl substituted was charged, the reaction vessel was purged with nitrogen under stirring, and the temperature was raised to 100 ° C under a nitrogen atmosphere. Thereafter, a monomer aqueous solution in which 78 parts of acrylic acid, 1 part of 30% NaOH aqueous solution, and 288 parts of water were mixed, and a mixed solution of 7 parts of ammonium persulfate and 113 parts of water were each maintained at 100 ° C. for 2 hours. It was dripped continuously into the container. Furthermore, the aqueous solution of copolymer (M-1) was obtained by making it react for 1 hour in the state hold | maintained at 100 degreeC. The content of polyethylene glycol allyl ether relative to the copolymer (M-1) was 11% by weight, and the content of water-soluble polyethylene glycol whose both terminal groups were hydrogen atoms was 0.7% by weight. This solution was adjusted to pH 7 with a 30% NaOH aqueous solution to obtain an aqueous solution of a salt (A-1) of a polycarboxylic acid copolymer having a weight average molecular weight of 16,000 and Mw / Mn1.8. The weight average molecular weight and Mw / Mn of the copolymer (M-1) were almost the same as the weight average molecular weight and Mw / Mn of the salt (A-1) of the copolymer.

<Production Example 2>
[Production of Polycarboxylic Acid Copolymer (M-2) and its Salt (A-2)]
1 part of water, 94 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added 20) in a glass reaction vessel equipped with a thermometer, a stirring device, a reflux device, a nitrogen introducing tube and a dropping device, and 4,4 ′ -1 part of a compound in which the 3 and 3 'positions of dihydroxydiphenylsulfone were allyl substituted was charged, the reaction vessel was purged with nitrogen under stirring, and the temperature was raised to 100 ° C under a nitrogen atmosphere. Thereafter, a monomer aqueous solution in which 14 parts of acrylic acid and 71 parts of water were mixed and a mixed liquid of 2 parts of ammonium persulfate and 29 parts of water were continuously dropped into a reaction vessel maintained at 100 ° C. for 1 hour each. Furthermore, the aqueous solution of copolymer (M-2) was obtained by making it react for 1 hour in the state hold | maintained at 100 degreeC. The content of polyethylene glycol allyl ether with respect to the copolymer (M-2) was 16% by weight, and the content of water-soluble polyethylene glycol in which both terminal groups were hydrogen atoms was 0.3%. This solution was adjusted to pH 7 with a 30% aqueous NaOH solution to obtain an aqueous solution of a salt (A-2) of a polycarboxylic acid copolymer having a weight average molecular weight of 17,000 and Mw / Mn1.5. The weight average molecular weight and Mw / Mn of the copolymer (M-2) were almost the same as the weight average molecular weight and Mw / Mn of the copolymer salt (A-2).

<Production Example 3>
[Production of Polycarboxylic Acid Copolymer (M-3) and its Salt (A-3)]
1 part of water, 94 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added 20) in a glass reaction vessel equipped with a thermometer, a stirring device, a reflux device, a nitrogen introducing tube and a dropping device, and 4,4 ′ -1 part of a compound in which the 3 and 3 'positions of dihydroxydiphenylsulfone were allyl substituted was charged, the reaction vessel was purged with nitrogen under stirring, and the temperature was raised to 100 ° C under a nitrogen atmosphere. Thereafter, an aqueous monomer solution obtained by mixing 11 parts of acrylic acid and 66 parts of water and a mixed solution of 1 part of ammonium persulfate and 29 parts of water were continuously added dropwise to a reaction vessel maintained at 100 ° C. for 1 hour each. Furthermore, the aqueous solution of copolymer (M-3) was obtained by making it react for 1 hour in the state hold | maintained at 100 degreeC. The content of polyethylene glycol allyl ether with respect to the copolymer (M-3) was 29% by weight, and the content of water-soluble polyethylene glycol in which both terminal groups were hydrogen atoms was 0.6%. This solution was adjusted to pH 7 with a 30% NaOH aqueous solution to obtain an aqueous solution of a polycarboxylic acid copolymer salt (A-3) having a weight average molecular weight of 11,000 and Mw / Mn 1.6. The weight average molecular weight and Mw / Mn of the copolymer (M-3) were almost the same as the weight average molecular weight and Mw / Mn of the salt (A-3) of the copolymer.

<Production Example 4>
[Production of Polycarboxylic Acid Copolymer (M-4) and its Salt (A-4)]
329 parts of water, 771 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added 10), and 4,4 ′ in a glass reaction vessel equipped with a thermometer, a stirring device, a reflux device, a nitrogen introduction tube and a dropping device -3 parts of the compound in which the 3 and 3 'positions of dihydroxydiphenylsulfone were substituted with allyl were charged, the reaction vessel was purged with nitrogen under stirring, and the temperature was raised to 100 ° C under a nitrogen atmosphere. Thereafter, an aqueous monomer solution obtained by mixing 92 parts of acrylic acid and 573 parts of water and a mixed solution of 11 parts of ammonium persulfate and 229 parts of water were continuously added dropwise to a reaction vessel maintained at 100 ° C. for 1 hour each. Furthermore, the aqueous solution of copolymer (M-4) was obtained by making it react for 1 hour in the state hold | maintained at 100 degreeC. The content of unsaturated polyethylene glycol allyl ether with respect to the copolymer (M-4) was 30% by weight, and the content of water-soluble polyethylene glycol in which both terminal groups were hydrogen atoms was 0.2%. . This solution was adjusted to pH 7 with a 30% NaOH aqueous solution to obtain an aqueous solution of a salt (A-4) of a polycarboxylic acid copolymer having a weight average molecular weight of 9,000 and Mw / Mn1.5. The weight average molecular weight and Mw / Mn of the copolymer (M-4) were almost the same as the weight average molecular weight and Mw / Mn of the salt (A-4) of the copolymer.

<Production Example 5>
[Production of Polycarboxylic Acid Copolymer (M-5) and its Salt (A-5)]
329 parts of water, 771 parts of polyethylene glycol monoallyl ether (average number of moles of ethylene oxide added 10), and 4,4 ′ in a glass reaction vessel equipped with a thermometer, a stirring device, a reflux device, a nitrogen introduction tube and a dropping device -3 parts of the compound in which the 3 and 3 'positions of dihydroxydiphenylsulfone were substituted with allyl were charged, the reaction vessel was purged with nitrogen under stirring, and the temperature was raised to 100 ° C under a nitrogen atmosphere. Thereafter, an aqueous monomer solution obtained by mixing 115 parts of acrylic acid and 600 parts of water and a mixed solution of 12 parts of ammonium persulfate and 228 parts of water were continuously added dropwise to a reaction vessel maintained at 100 ° C. for 1 hour each. Furthermore, the aqueous solution of copolymer (M-5) was obtained by making it react for 1 hour in the state hold | maintained at 100 degreeC. The content of polyethylene glycol allyl ether in the copolymer (M-5) was 22% by weight, and the content of water-soluble polyethylene glycol in which both terminal groups were hydrogen atoms was 0.1%. This solution was adjusted to pH 7 with a 30% aqueous NaOH solution to obtain an aqueous solution of a salt (A-5) of a polycarboxylic acid copolymer having a weight average molecular weight of 11,000 and Mw / Mn 1.6. The weight average molecular weight and Mw / Mn of the copolymer (M-5) were almost the same as the weight average molecular weight and Mw / Mn of the salt (A-5) of the copolymer.

<Production Example 6>
[Production of Polycarboxylic Acid Copolymer (N-1) and its Salt (B-1)]
A glass reaction vessel equipped with a thermometer, a stirrer, a reflux device, a nitrogen introduction tube and a dropping device was charged with 1052 parts of water, the reaction vessel was purged with nitrogen under stirring, and the temperature was raised to 100 ° C. under a nitrogen atmosphere. Thereafter, 323 parts of methoxypolyethylene glycol methacrylate (average number of added moles of ethylene oxide: 13), 2 parts of compound in which 3 and 3 'positions of 4,4'-dihydroxydiphenylsulfone were allyl substituted, 39 parts of methacrylic acid, and water A monomer solution mixed with 357 parts and a mixed solution of 7 parts of sodium persulfate and 113 parts of water were continuously added dropwise to a reaction vessel maintained at 100 ° C. for 2 hours each. Furthermore, the aqueous solution of copolymer (N-1) was obtained by making it react for 1 hour in the state hold | maintained at 100 degreeC. This solution was adjusted to pH 7 with a 30% NaOH aqueous solution to obtain an aqueous solution of a salt (B-1) of a polycarboxylic acid copolymer having a weight average molecular weight of 19,000 and Mw / Mn 1.6. The weight average molecular weight and Mw / Mn of the copolymer (N-1) were almost the same as the weight average molecular weight and Mw / Mn of the salt (B-1) of the copolymer.

<Production Example 7>
[Production of Polycarboxylic Acid Copolymer (N-2) and its Salt (B-2)]
100 parts of water was charged into a glass reaction vessel equipped with a thermometer, a stirrer, a reflux device, a nitrogen introduction tube and a dropping device, the reaction vessel was purged with nitrogen under stirring, and the temperature was raised to 75 ° C. under a nitrogen atmosphere. Thereafter, an aqueous monomer solution in which 90 parts of methoxypolyethylene glycol methacrylate (average number of added moles of ethylene oxide 67), 5 parts of methacrylic acid, 21 parts of water, and 0.3 part of 3-mercaptopropionic acid were mixed, and sodium persulfate A mixed solution of 1 part and 29 parts of water was continuously dropped into a reaction vessel maintained at 75 ° C. for 2 hours each. Furthermore, the aqueous solution of copolymer (N-2) was obtained by making it react for 1 hour in the state hold | maintained at 75 degreeC. This solution was adjusted to pH 7 with a 30% NaOH aqueous solution to obtain an aqueous solution of a salt (B-2) of a polycarboxylic acid copolymer having a weight average molecular weight of 56,000 and Mw / Mn 2.6. The weight average molecular weight and Mw / Mn of the copolymer (N-2) were almost the same as the weight average molecular weight and Mw / Mn of the copolymer salt (B-2).

<Production Example 8>
[Production of Polycarboxylic Acid Copolymer (N-3) and its Salt (B-3)]
752 parts of water was charged into a glass reaction vessel equipped with a thermometer, a stirrer, a reflux device, a nitrogen introduction tube and a dropping device, the reaction vessel was purged with nitrogen under stirring, and the temperature was raised to 75 ° C. under a nitrogen atmosphere. Thereafter, an aqueous monomer solution in which 600 parts of methoxypolyethylene glycol methacrylate (average number of added moles of ethylene oxide 67), 29 parts of acrylic acid, 133 parts of water, and 2 parts of 3-mercaptopropionic acid were mixed, and 3 parts of sodium persulfate And 97 parts of water were continuously added dropwise to a reaction vessel maintained at 75 ° C. for 2 hours each. Furthermore, the aqueous solution of copolymer (N-3) was obtained by making it react for 1 hour in the state hold | maintained at 75 degreeC. This solution was adjusted to pH 7 with a 30% aqueous NaOH solution to obtain an aqueous solution of a salt of a polycarboxylic acid copolymer (B-3) having a weight average molecular weight of 38,000 and Mw / Mn2.1. The weight average molecular weight and Mw / Mn of the copolymer (N-3) were almost the same as the weight average molecular weight and Mw / Mn of the salt (B-3) of the copolymer.

<Production Example 9>
[Production of Polycarboxylic Acid Copolymer (N-4) and its Salt (B-4)]
739 parts of water was charged into a glass reaction vessel equipped with a thermometer, a stirrer, a reflux device, a nitrogen introduction tube, and a dropping device, the reaction vessel was purged with nitrogen under stirring, and the temperature was raised to 75 ° C. under a nitrogen atmosphere. Thereafter, an aqueous monomer solution obtained by mixing 600 parts of methoxypolyethylene glycol methacrylate (average number of moles of ethylene oxide added 67), 22 parts of acrylic acid, 127 parts of water, and 2 parts of 3-mercaptopropionic acid, and 2 parts of sodium persulfate And 98 parts of water were each continuously added dropwise to the reaction vessel maintained at 75 ° C. for 2 hours. Furthermore, the aqueous solution of copolymer (N-4) was obtained by making it react for 1 hour in the state hold | maintained at 75 degreeC. This solution was adjusted to pH 7 with a 30% aqueous NaOH solution to obtain an aqueous solution of a salt (B-4) of a polycarboxylic acid copolymer having a weight average molecular weight of 41,000 and Mw / Mn2.1. The weight average molecular weight and Mw / Mn of the copolymer (N-4) were almost the same as the weight average molecular weight and Mw / Mn of the salt (B-4) of the copolymer.

Examples 1-6 and Comparative Examples 1-7 <mortar test>
Polycarboxylic acid copolymer (M-1), polycarboxylic acid polymer salts (A-1) and (A-2), polycarboxylic acid copolymer (N-1), Carboxylic acid polymer salts (B-1), (B-2), (B-3) and (B-4), sulfonic acid dispersants (C) and oxycarboxylic acid dispersants shown below (D) was blended in the combinations shown in Table 1 to prepare a cement admixture.
・ Sulphonic acid dispersant (C) (Lignin sulfonic acid cement dispersant: Nippon Paper Chemical Co., Ltd., trade name: Sunflow RH) LG agent ・ Oxycarboxylic acid dispersant (D) (sodium gluconate cement Dispersant: Fuso Chemical Industry Co., Ltd., trade name: C-PARN)
In addition, each polycarboxylic acid-type copolymer and its salt were added to cement in the state of the aqueous solution obtained by each manufacture example.

  The fine aggregate, cement, water and the cement admixture shown in Table 1 were added as follows, and mortar was prepared by mechanical kneading with a mortar mixer. The water / cement mass ratio (W / C) of the mortar was 52.5%. Each mortar was evaluated for mortar flow and J14 funnel flow time. The results are shown in Table 1.

Normal Portland cement (Mitsubishi Ube, Ltd., specific gravity 3.16)
210g
Ordinary Portland cement (manufactured by Taiheiyo Cement Co., Ltd., specific gravity 3.16)
210g
Normal Portland cement (specific gravity 3.16 manufactured by Tokuyama Corporation)
209g
330 g of tap water
Kakegawa land sand (fine aggregate, specific gravity 2.58, surface water 0.4%) 1069g
Cement admixture (solid content conversion) See Table 1

<Measurement of mortar flow value>
The above-mentioned mortar is packed in a hollow cylindrical mini slump cone with a bottom diameter of 20 cm, a top diameter of 10 cm, and a height of 30 cm, and the average value of the two directions of the mortar spread on the table when the mini slump cone is lifted vertically. Was the mortar flow value. The evaluation of the slump retention was performed by repeating the above operation after a predetermined time and determining the change with time of the mortar flow. The higher the mortar flow value after change with time, the better the slump retention of the admixture.

<Measurement of J14 funnel flow time>
A cylindrical J14 funnel having an upper end of 70 mm, a lower end of 14 mm, and a height of 392 mm was filled with a mortar having a mortar flow value of 230 mm, and the time until the mortar flowed down the J14 funnel was measured. It is estimated that the shorter the J14 funnel flow time, the lower the viscosity of the mortar.

  In Table 1, “addition rate” of the cement admixture indicates a solid content addition rate of the admixture to the cement.

  As is apparent from Table 1, the mortar of the example showed a high mortar flow equivalent to the comparative example. Moreover, the J14 funnel flow time of the mortar of the example was shorter than that of the mortar of the comparative example. As a result, when the cement admixture of the present invention exhibits excellent cement dispersibility and water-reducing properties, and is excellent in slump loss prevention performance, and when it is used as a cement composition, the viscosity of the cement composition is reduced. It shows that it can be reduced.

Claims (12)

Monomer (I) represented by the following general formula (1) 5 to 95% by weight, unsaturated monocarboxylic acid monomer (II) 1 to 50% by weight, and monomer (I) and / or Or, a polycarboxylic acid copolymer obtained by copolymerizing a monomer containing 0 to 10% by weight of a monomer (III) copolymerizable with (II) or a salt thereof (A),
The monomer (IV) represented by the following general formula (2) exceeds 50% by weight and is 95% by weight or less, the unsaturated monocarboxylic acid monomer (II) 1 to 50% by weight, and the monomer (II) and / or (IV) copolymerizable monomer (V) obtained by copolymerizing a monomer containing 0.01 to 10% by weight, and gel permeation chromatography (GPC) ), A polycarboxylic acid copolymer having a weight average molecular weight measured in terms of polyethylene glycol of 10,000 to 56,000 or a salt thereof (B),
A sulfonic acid compound (C);
A cement admixture having oxycarboxylic acid or sugar (D),
The monomer (V) includes a (meth) allyl bisphenol monomer,
Each content ratio of (A), (B), (C) and (D) is (A) :( B) :( C) :( D) = 26 to 35 % by weight: 12 to 35 % by weight: 5 to 50 % by weight: Cement admixture that is 18 to 25 % by weight (provided that (A) + (B) + (C) + (D) = 100% by weight).

(In the formula, R ¹ represents an alkenyl group having 2 to 5 carbon atoms. A ¹ O is the same or different and represents an oxyalkylene group having 2 to 18 carbon atoms. N1 represents an oxyalkylene group. (The average number of moles added represents a number of 1 to 40. R ² represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms.)

(In the formula, R ³ , R ⁴ and R ⁵ each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. M represents a number of 0 to ^2. A ² O is the same. Or, differently, it represents an oxyalkylene group having 2 to 18 carbon atoms, n2 is the average number of added moles of the oxyalkylene group, and represents a number of 1 to 80. X is a hydrogen atom or 1 to 1 carbon atoms. Represents 30 hydrocarbon groups.) The cement admixture according to claim 1, wherein the monomer ( V) is a (meth) allylbisphenol monomer.   The cement admixture according to claim 1 or 2, wherein a weight average molecular weight of the polycarboxylic acid copolymer or a salt thereof (A) is 5,000 to 50,000 in terms of polyethylene glycol.   The cement admixture according to any one of claims 1 to 3, wherein the polycarboxylic acid copolymer or a salt thereof (A) is a salt obtained by neutralizing the copolymer with an alkaline substance.   The cement admixture according to any one of claims 1 to 4, wherein the polycarboxylic acid copolymer or a salt thereof (B) is a salt obtained by neutralizing the copolymer with an alkaline substance.   The cement admixture according to any one of claims 1 to 5, wherein the sulfonic acid compound (C) has a sulfonic acid group in the molecule.   The cement admixture according to any one of claims 1 to 6, wherein the sulfonic acid compound (C) has an aromatic group in the molecule.   The cement admixture according to any one of claims 1 to 7, further comprising a (poly) alkylene glycol alkenyl ether monomer (E).   The cement according to claim 8, wherein a content ratio of the (poly) alkylene glycol alkenyl ether monomer (E) is 1 to 90% by weight with respect to the polycarboxylic acid copolymer or a salt (A) thereof. Admixture.   The cement admixture according to any one of claims 1 to 9, further comprising a water-soluble polyalkylene glycol (F) in which both terminal groups are hydrogen atoms.   The content rate of the water-soluble polyalkylene glycol (F) whose both terminal groups are hydrogen atoms is less than 1 weight% with respect to a polycarboxylic acid-type copolymer or its salt (A). Cement admixture.   The cement composition containing the cement admixture as described in any one of Claims 1-11.