JP2009114040A - Copolymer composition for concrete admixture, concrete admixture, and cement composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a copolymer composition for a concrete admixture, capable of giving excellent flowability to a cement composition, capable of exerting high flowability for a long time, and simultaneously capable of giving, to the cement composition, a viscosity easily handleable in a site for handling the cement composition; and a concrete admixture and a cement composition, both containing the polymer composition. <P>SOLUTION: The copolymer composition for a concrete admixture contains a polycarboxylic acid-based copolymer and a polyamine-polyalkylene oxide adduct. The polycarboxylic acid-based copolymer has a polyalkylene glycol chain with an average repeating number of an alkylene glycol unit is 8 or more and a weight average molecular weight (Mw) of less than 10,000. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a copolymer composition for a concrete admixture, a concrete admixture and a cement composition. More specifically, the present invention relates to a copolymer composition for a concrete admixture that can be used as a water reducing agent such as a cement composition, a concrete admixture containing the copolymer composition, and a cement composition containing the concrete admixture.

Concrete admixtures are widely used in cement compositions such as cement paste, mortar and concrete, and are indispensable for constructing civil engineering and building structures from cement compositions. Such a concrete admixture is used as a water reducing agent, etc., and has the effect of improving the strength and durability of the cured product by reducing the water content of the cement composition by increasing the fluidity of the cement composition. . As a water reducing agent, a water reducing agent such as a naphthalene type has been conventionally used. However, a polycarboxylic acid type water reducing agent that exhibits higher water reducing performance than this has been proposed (for example, see Patent Document 1). Therefore, it has come to have many use results as a high performance AE water reducing agent. However, with such a water reducing agent, although the fluidity of the cement composition is sufficient immediately after production, the fluidity is not sufficient over time, so that it can exhibit high fluidity even after a long time has passed. There is room for improvement to improve the workability by reducing the viscosity of the cement composition.

Therefore, in order to improve the fluidity of such a cement composition, fluidity retention with time, and viscosity, a technique using a polycarboxylic acid copolymer in which the molecular weight and molecular weight distribution are adjusted to a specific range ( For example, Patent Documents 2 and 3) and a method of using a mixture of a plurality of polycarboxylic acid copolymers having a specific structure (for example, see Patent Documents 4 and 5) have been proposed. Although it has become possible to improve each of the various performances by the method, these performances have not been improved at the same time, and further technical improvements are being demanded. .

As another method for adjusting the viscosity of concrete by imparting some hydrophobicity to the polycarboxylic acid polymer and expressing hydrophobic interaction in the aqueous phase of concrete, for example, a hydrophobic monomer is used. A method for polymerizing (for example, see Patent Document 6) and a method for introducing a hydrophobic group such as propylene oxide into a polyalkylene glycol chain that is a cement dispersing group (for example, see Patent Document 7) have also been proposed. However, there is room for ingenuity to make it possible to exhibit higher performance, and there is also room for ingenuity to increase productivity and economy by sufficiently suppressing the formation of gel during polymerization. .
Similarly, in order to improve hydrophobicity, a method of shortening the polyalkylene glycol chain itself, which is a cement dispersing group, has also been proposed (see, for example, Patent Document 7). In order to further reduce the addition amount, there is room for further improvement in dispersibility.

On the other hand, in addition to the contrivance of the copolymer, various methods for separately adding an auxiliary agent capable of adjusting the physical properties of the concrete have been proposed. For example, a method in which a polycarboxylic acid polymer and a polyalkyleneimine alkylene oxide adduct are used in combination has been developed (see, for example, Patent Documents 8 to 10). However, in these methods, there has been room for improvement to make it possible to adjust the viscosity of the concrete more sufficiently, or to reduce the amount added to the concrete and increase the economy.
JP 58-74552 A JP-A-9-86990 JP 2005-281022 A JP 2006-069859 A JP 2004-256320 A JP 2006-525938 A JP 2006-525219 A JP 2000-109357 A JP 2005-126279 A JP 2005-200288 A

The present invention has been made in view of the above-mentioned present situation, can impart excellent fluidity to the cement composition, and can exhibit high fluidity over a long period of time, while at the same time handling the cement composition. It is an object of the present invention to provide a copolymer composition for a concrete admixture that can be made viscous so that it can be easily operated, and a concrete admixture and a cement composition comprising the same.

As a result of various studies on materials suitable for concrete admixture, the present inventors have demonstrated that the polycarboxylic acid copolymer having a polyalkylene glycol in the side chain exhibits excellent water reduction performance for cement compositions and the like. In particular, the weight average molecular weight (Mw) of the copolymer is specified to be less than 10,000, and the average added mole number of the alkylene glycol unit of the polyalkylene glycol chain is specified to be 8 or more. When used in combination with an alkylene oxide adduct, sufficient fluidity can be imparted to the cement composition, the fluidity of the cement composition is stable over time, and the viscosity is reduced. It has been found that a cement composition having excellent properties can be provided.

Here, the concrete admixture usually has a fluidity (= dispersibility, water reduction), retention (= stability of fluidity over time), and good viscosity (= workability, handling of cement composition). Various performances such as ease, the sense of unity between the cement paste and the aggregate in the cement composition, and pumpability are required. However, conventional concrete admixtures exhibit these performances simultaneously. However, if one of the performances was to be improved, the other performance would be significantly impaired. However, the inventors of the present invention have appropriately specified the constitution of the polycarboxylic acid copolymer as described above, and used it together with the polyamine polyalkylene oxide adduct to thereby improve the fluidity, retention and work of the cement composition. It has been found that any performance such as property (good viscosity) can be exhibited at the same time without any loss, and one or more performances can be further enhanced.

It has also been found that by using the polycarboxylic acid copolymer and the polyamine polyalkylene oxide adduct in combination, the kneading speed of the cement composition can be improved and the productivity can be increased. It has also been found that the strength of objects can be sufficiently improved.
Furthermore, in the copolymer composition containing such a polycarboxylic acid copolymer (A) and a polyamine polyalkylene oxide adduct, two or more of the copolymers (A) may be used, or the copolymer It has been found that, when a copolymer (B) different from (A) is used in combination, various properties such as sufficient fluidity, retainability and workability required for a cement composition can be exhibited in a balanced manner. Among the combinations (B), when a copolymer having a weight average molecular weight of 10,000 or more and an An value calculated from the amount of the carboxylic acid group and the polyalkylene glycol chain length is a specific value or more is used. The inventors have found that the performance is good and have reached the present invention.

That is, the present invention is a copolymer composition for a concrete admixture containing a polycarboxylic acid copolymer (A) and a polyamine polyalkylene oxide adduct (C), wherein the polycarboxylic acid copolymer ( A) is a copolymer composition for a concrete admixture having a polyalkylene glycol chain having an average number of repeating alkylene glycol units of 8 or more and a weight average molecular weight (Mw) of less than 10,000.
The present invention is also a concrete admixture comprising the above-described copolymer composition for a concrete admixture.
The present invention is also a cement composition comprising the above concrete admixture.
The present invention is described in detail below.

The copolymer composition for concrete admixture of the present invention comprises a polycarboxylic acid copolymer (A) and a polyamine polyalkylene oxide adduct (C).
The polycarboxylic acid copolymer (A) (hereinafter also referred to as “copolymer (A)”) has a polyalkylene glycol in the side chain, and the average number of repeating alkylene glycol units in the chain is 8. The above is appropriate. As a result, the fluidity, retainability, and workability of the cement composition can all be made well in a balanced manner. However, if it is less than 8, these performances can be simultaneously satisfied with high performance. In addition, a gel is generated during the polymerization reaction for obtaining the copolymer (A), and the productivity of the copolymer may not be sufficient. The average number of repetitions is preferably 9 or more, more preferably 10 or more. On the other hand, if the average number of repetitions exceeds 300, problems in production may occur, and when used as a concrete admixture, the viscosity of the cement composition may increase, and workability may not be sufficient. Therefore, from the viewpoint of manufacturing, it is preferable that it is 300 or less. Preferably, it is 150 or less, more preferably 100 or less, and from the viewpoint of viscosity, it is further preferably 50 or less, still more preferably 25 or less, particularly preferably 15 or less, most preferably. 10 or less.

In the region where the average number of repetitions is relatively small, a slight change in the number greatly affects the performance of the copolymer (A) as a cement admixture. In an area of 10 or less, the difference of 1 in the number is a difference of 10% or more. Further, since the copolymer (A) has a small weight average molecular weight of less than 10,000 and a short main chain portion as will be described later, the side chain is a polyalkylene glycol chain as compared with the main chain portion of the copolymer. It can be said that the influence on the performance is significantly large.

The copolymer (A) also suitably has a weight average molecular weight of less than 10,000. As a result, it becomes possible to improve the workability by reducing the viscosity while maintaining sufficient retention of the cement composition, but if it is 10,000 or more, there is a possibility that these performances cannot be sufficiently exhibited. is there. Preferably it is 9500 or less, More preferably, it is 9200 or less, More preferably, it is 9000 or less, Most preferably, it is 8800 or less. In addition, the copolymer (A) has a weight average molecular weight of preferably 2000 or more from the viewpoint that adsorbing power increases as the weight average molecular weight increases as the copolymer (A) adsorbs to cement particles to some extent. . More preferably, it is 3000 or more, More preferably, it is 4000 or more, Especially preferably, it is 4500 or more, Most preferably, it is 5000 or more.

The molecular weight distribution (= weight average molecular weight (Mw) / number average molecular weight (Mn)) of the copolymer (A) is not particularly limited, but is preferably more than 1.5. Here, if the Mw / Mn of the copolymer (A) is too small or too large, it may affect various performances. This is because the cement particles have a certain particle size distribution. It is presumed that when / Mn also has a distribution suitable to some extent, it can be adsorbed on cement particles with a wide particle size and exhibit performance. More preferably, it is 1.52 or more, More preferably, it is 1.54 or more, Especially preferably, it is 1.56 or more, Most preferably, it is 1.58 or more. Moreover, it is preferable that it is 2 or less. More preferably, it is 1.9 or less, More preferably, it is 1.8 or less, Especially preferably, it is 1.7 or less, Most preferably, it is 1.65 or less.

In the copolymer (A), the molecular weight distribution (Mw / Mn) is preferably regarded as uniform. Here, “uniform” does not mean “monodisperse”. This is because the (co) polymer usually has a molecular weight distribution. In order to obtain a monodisperse (co) polymer in a strict sense, it is necessary to use a method such as a living polymerization method or molecular weight fractionation. In the GPC (gel permeation chromatography) chromatogram of the copolymer (A), when the chromatogram curve on the higher molecular weight side than Mp (peak top molecular weight) is a gentle curve, it can be regarded as a uniform molecular weight distribution. . On the other hand, when there is a remarkable bent portion (shoulder) on the high molecular weight side or when there are a plurality of peak tops, the molecular weight distribution cannot be said to be uniform.
The copolymer (A) having a shoulder on the high molecular weight side or having a plurality of peak tops can be obtained, for example, by changing the monomer amount, the chain transfer agent amount, and other conditions during the polymerization process. it can. Since such a copolymer can be regarded as a mixture of a copolymer (A) satisfying the above-mentioned various conditions such as molecular weight and a copolymer (AA) having different molecular weights, the molecular weight is calculated separately. When the copolymer (AA) satisfies a predetermined condition, it can also be regarded as a copolymer (B) to be described later (hereinafter sometimes referred to as a copolymer (AB)).

The copolymer (A) containing the copolymers (AA) and (AB) having different molecular weights as described above is more preferable as described in the present invention than the copolymer (A) having a uniform molecular weight distribution. Performance may not be sufficient. Therefore, it is preferable that the content of the copolymer (A) is sufficiently high. In the RI (differential refractive index) area ratio of GPC, the area ratio of the copolymer (A) with respect to 100% of the total of the copolymer (A) and the copolymer (AA) or the copolymer (AB) is: It is preferably 70% or more, more preferably 80% or more, more preferably 90% or more, and more preferably 95% or more. In the calculation of the area ratio in this case, the copolymer (A) and the copolymer (AA) or copolymer (AB) shall be divided vertically at the intersection of the tangent lines of the RI chromatogram.
In the GPC chromatogram, the chromatogram curve on the lower molecular weight side than Mp (peak top molecular weight) often has peaks derived from dimers, trimers and the like. This is due to the separation conditions and should not be used to determine the uniformity of the molecular weight distribution.

Further, since the copolymer (A) has a small Mw of less than 10,000, when the molecular weight is measured under GPC conditions described later, it is derived from the oligomer, residual monomer and monomer-derived compound in addition to the polymer peak in the chromatogram. A peak may appear. The monomer-derived compound refers to a compound that appears in almost the same elution capacity as that of the monomer and in which the double bond of the monomer is lost by a radical or the like.
In the molecular weight analysis of the copolymer (A), the residual monomer and the monomer-derived compound are excluded from the definition because they are not included in the polymer and have little influence on the performance. Oligomers such as dimer and trimer are included in the polymer. Further, when impurity peaks derived from monomers or raw materials are detected, they are excluded as much as possible.

The molecular weight in this specification is a measured value by gel permeation chromatography (GPC), and is preferably measured under the following conditions.
<GPC measurement conditions>
Column used: manufactured by Tosoh Corporation, TSK guard column SWXL + TSKgel G4000SWXL + G3000SWXL + G2000SWXL;
Eluent: Dissolve 115.6 g of sodium acetate trihydrate in a mixed solvent of 10999 g of water and 6001 g of acetonitrile, and use a solution further adjusted to pH 6.0 with acetic acid;
Sample injection amount: 100 μL;
Flow rate: 0.8 mL / min;
Column temperature: 40 ° C .;
Detector: Nippon Waters, 2414 differential refraction detector;
Analysis software: Nippon Waters, Empower Software + GPC option;
Standard material for creating calibration curve: polyethylene glycol [peak top molecular weight (Mp) 272500, 219300, 107000, 50000, 24000, 12600, 7100, 4250, 1470];
Calibration curve: Prepared by cubic equation based on Mp value and elution time of polyethylene glycol;
A sample is prepared by dissolving an aqueous polymer solution with the above eluent so that the polymer concentration is 0.5 mass%.

<Analysis of molecular weight>
In the obtained RI chromatogram, the portions that are flat and stable in the baseline immediately before and after elution of the polymer are connected by a straight line to detect and analyze the polymer. However, when the monomer, impurities derived from the monomer, etc. are measured partially overlapping with the polymer peak, the polymer part and the monomer part are separated by vertically dividing them at the most concave part of the overlapping part of the polymer and only the polymer part. Measure molecular weight and molecular weight distribution. If the polymer part and the rest cannot be completely overlapped and separated, they are calculated together.

As the copolymer (A), if the copolymer has a polyalkylene glycol in the side chain and the average number of repeating units and the weight average molecular weight of the alkylene glycol unit are specified as described above, its structure, etc. Is not particularly limited, for example, obtained by copolymerizing an unsaturated monomer composition essentially comprising an unsaturated carboxylic acid monomer and an unsaturated polyalkylene glycol monomer It is preferable that In addition, these monomer components can use 1 type (s) or 2 or more types, respectively.

Here, the carboxylic acid group possessed by the unsaturated carboxylic acid monomer imparts water-solubility and adsorption force to inorganic fine particles such as cement to the copolymer (A). When using the copolymer (A) as a concrete admixture, the content of the unsaturated carboxylic acid monomer is used to produce the copolymer (A) in order to express the required performance in a well-balanced manner. It is preferable that the content is 5% by mass or more with respect to 100% by mass of all the monomer components (unsaturated monomer composition) used in the above. More preferably, it is 10 mass% or more, More preferably, it is 15 mass% or more. Further, from the same viewpoint, it is preferably 40% by mass or less. More preferably, it is 35 mass% or less, More preferably, it is 30 mass% or less, Especially preferably, it is 25 mass% or less, Most preferably, it is 22.5 mass% or less.

In addition, the polyalkylene glycol chain of the unsaturated polyalkylene glycol-based monomer imparts water-solubility and dispersibility of inorganic fine particles such as cement to the copolymer (A). When the copolymer (A) is used as a concrete admixture, the content of the unsaturated polyalkylene glycol monomer is used to produce the copolymer (A) in order to express the required performance in a balanced manner. It is preferable that the amount be 60% by weight or more with respect to 100% by weight of all the monomer components (unsaturated monomer composition) used for the treatment. More preferably, it is 65 mass% or more, More preferably, it is 70 mass% or more, Especially preferably, it is 75 mass% or more, Most preferably, it is 77.5 mass% or more. From the same viewpoint, it is preferably 95% by mass or less. More preferably, it is 90 mass% or less, More preferably, it is 85 mass% or less, Especially preferably, it is 82.5 mass% or less, Most preferably, it is 80 mass% or less.

As a more preferable form as the copolymer (A), for example, the following general formula (1);

(In the formula, R ¹ , R ² and R ³ are the same or different and each represents a hydrogen atom, a methyl group or — (CH ₂ ) x COOM ^2. Note that — (CH ₂ ) x COOM ² represents —COOM ¹ or other _- (CH ²⁾ _xCOOM 2 and good .x also form an anhydride is .M ¹ and ^{M 2} is an integer of 0 to 2 are the same or different, a hydrogen atom, a monovalent metal atom Represents a divalent metal atom, a trivalent metal atom, a quaternary ammonium base or an organic amine base.) (Hereinafter referred to as “monomer (a1)”) And the following general formula (2);

(.AO ^wherein, R 4, ^{R 5} and ^{R 6} are the same or different, .R ⁷ represents a hydrogen atom or a methyl group, represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms are the same Or, differently, it represents one or more of oxyalkylene groups having 2 to 18 carbon atoms, and when there are two or more oxyalkylene groups represented by AO, these groups are introduced in a block form. And y is an integer of 0 to 2. z is 0 or 1. n1 represents the average number of added moles of the oxyalkylene group; An unsaturated monomer composition comprising an unsaturated polyalkylene glycol monomer (b1) (hereinafter also referred to as “monomer (b1)”) represented by the formula: Is obtained by copolymerization.

In the general formula (1), examples of the metal atom represented by M ¹ and M ² include monovalent metal atoms such as alkali metal atoms such as lithium, sodium and potassium; alkaline earth metals such as calcium and magnesium And divalent metal atoms such as atoms; trivalent metal atoms such as aluminum and iron. Examples of the organic amine base include alkanolamine groups such as ethanolamine group, diethanolamine group, triethanolamine group, and triethylamine group.

Specific examples of the monomer (a1) represented by the general formula (1) include, for example, monocarboxylic acid monomers such as acrylic acid, methacrylic acid, and crotonic acid; maleic acid, itaconic acid, fumaric acid, and the like. Dicarboxylic acid monomers of the above; anhydrides or salts of these carboxylic acids (for example, alkali metal salts, alkaline earth metal salts, trivalent metal salts, ammonium salts, organic amine salts) and the like. Among these, acrylic acid, methacrylic acid, maleic acid, maleic anhydride and salts thereof are preferable from the viewpoint of polymerizability, and acrylic acid, methacrylic acid and salts thereof are more preferable.

In the general formula (2), the hydrocarbon group having 1 to 20 carbon atoms represented by ^{R 7,} aliphatic alkyl group having 1 to 20 carbon atoms, alicyclic alkyl group having 3 to 20 carbon atoms, carbon A C2-C20 alkenyl group, a C2-C20 alkynyl group, a C6-C20 aryl group, etc. are mentioned. R ⁷ is preferably a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, more preferably a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, still more preferably a hydrogen atom or a methyl group. is there.

In the general formula (2), the polyalkylene glycol chain represented by (AO) _n1 is preferably composed mainly of an oxyethylene group having 2 carbon atoms (ethylene oxide). As a result, the copolymer (A) becomes sufficiently hydrophilic, and sufficient water-solubility and cement particle dispersion performance are imparted to the copolymer (A).
Here, “mainly” means, for example, 50 to 100 mol% when oxyethylene groups in 100 mol% of all oxyalkylene groups (alkylene glycol units) constituting the polyalkylene glycol chain are expressed in mol%. It is preferable that If it is less than 50 mol%, the hydrophilicity of the oxyalkylene group may not be sufficient, and the dispersion performance of cement particles may not be sufficiently imparted. More preferably, it is 60 mol% or more, More preferably, it is 70 mol% or more, Especially preferably, it is 80 mol% or more, Most preferably, it is 90 mol% or more.

The polyalkylene glycol chain represented by the above (AO) _n1 may also include a part of the oxyalkylene group having 3 or more carbon atoms having higher hydrophobicity. When such a hydrophobic group is introduced, when used as a cement dispersant, the viscosity of the cement composition is adjusted due to the light hydrophobic interaction between polyalkylene glycol chains in an aqueous solution. This is because may be improved. When introducing an oxyalkylene group having 3 or more carbon atoms, the amount introduced is, for example, to maintain sufficient water solubility with respect to 100 mol% of all oxyalkylene groups (alkylene glycol units) constituting the polyalkylene glycol chain. Is preferably 50 mol% or less. More preferably, it is 25 mol% or less, More preferably, it is 10 mol% or less. Moreover, it is preferable that it is 1 mol% or more for workability | operativity improvement. More preferably, it is 2.5 mol% or more, More preferably, it is 5 mol% or more.
As the oxyalkylene group having 3 or more carbon atoms, a propylene oxide group and a butylene oxide group are preferable from the viewpoint of ease of production, and among them, a propylene oxide group is more preferable.

When the polyalkylene glycol chain is composed of an oxyethylene group having 2 carbon atoms and an oxyalkylene group having 3 or more carbon atoms, these sequences may be random or block, When the block arrangement is used, the hydrophilicity of the hydrophilic block is expressed more strongly than the random arrangement, and the hydrophobicity of the hydrophobic block seems to be expressed more strongly. This is preferable because workability is further improved. In particular, it is preferably arranged in an ABA block shape as (oxygen group having 2 carbon atoms)-(oxyalkylene group having 3 or more carbon atoms)-(oxyethylene group having 2 carbon atoms).

In the above general formula (2), n1 is a number of 8 to 300, but if it exceeds 300, problems in production occur, and the viscosity of the cement composition becomes high when used as a concrete admixture. May not be sufficient. As described above, from the viewpoint of production, n1 is preferably 300 or less, preferably 150 or less, more preferably 100 or less, and from the viewpoint of viscosity, more preferably 50 or less, More preferably, it is 25 or less, particularly preferably 15 or less, and most preferably 10 or less.
As described above, n1 is suitably 8 or more, preferably 9 or more, more preferably 10 or more, from the viewpoint of the balance of fluidity, retention and workability of the cement composition as described above. is there.
The unsaturated polyalkylene glycol monomer (b1) represented by the general formula (2) may be a mixture of one or more of n1 = 0 or more, such as gel reduction during production. Therefore, in order to provide sufficient water solubility, the average polyalkylene glycol chain repeating unit (n1) is set to average n1 ≧ 8.

Specific examples of the monomer (b1) represented by the general formula (2) include an unsaturated alcohol polyalkylene glycol adduct and a polyalkylene glycol ester monomer.
The unsaturated alcohol polyalkylene glycol adduct may be a compound having a structure in which a polyalkylene glycol chain is added to an alcohol having an unsaturated group. The polyalkylene glycol ester-based monomer may be a monomer having a structure in which an unsaturated group and a polyalkylene glycol chain are bonded via an ester bond. Ester compounds are preferred, and (alkoxy) polyalkylene glycol mono (meth) acrylate is particularly preferred.

Examples of the unsaturated alcohol polyalkylene glycol adduct include vinyl alcohol alkylene oxide adduct, (meth) allyl alcohol alkylene oxide adduct, 3-buten-1-ol alkylene oxide adduct, isoprene alcohol (3-methyl- 3-buten-1-ol) alkylene oxide adduct, 3-methyl-2-buten-1-ol alkylene oxide adduct, 2-methyl-3-buten-2-ol alkylene oxide adduct, 2-methyl-2 -Butene-1-ol alkylene oxide adducts and 2-methyl-3-buten-1-ol alkylene oxide adducts are preferred.

Specific examples of the unsaturated alcohol polyalkylene glycol adduct include, for example, polyethylene glycol monovinyl ether, polyethylene glycol monoallyl ether, polyethylene glycol mono (2-methyl-2-propenyl) ether, polyethylene glycol mono (2-butenyl). Ether, polyethylene glycol mono (3-methyl-3-butenyl) ether, polyethylene glycol mono (3-methyl-2-butenyl) ether, polyethylene glycol mono (2-methyl-3-butenyl) ether, polyethylene glycol mono (2- Methyl-2-butenyl) ether, polyethylene glycol mono (1,1-dimethyl-2-propenyl) ether, polyethylene polypropylene glycol mono (3-methyl-3-butene) Nyl) ether, methoxy polyethylene glycol mono (3-methyl-3-butenyl) ether, ethoxy polyethylene glycol mono (3-methyl-3-butenyl) ether, 1-propoxy polyethylene glycol mono (3-methyl-3-butenyl) ether , Cyclohexyloxypolyethylene glycol mono (3-methyl-3-butenyl) ether, phenoxypolyethyleneglycolmono (3-methyl-3-butenyl) ether, methoxypolyethyleneglycolmonoallylether, ethoxypolyethyleneglycolmonoallylether, phenoxypolyethyleneglycolmono Allyl ether, methoxypolyethylene glycol mono (2-methyl-2-propenyl) ether, ethoxypolyethylene glycol mono (2-methyl -2-propenyl) ether, phenoxy polyethylene glycol mono (2-methyl-2-propenyl) ether and the like.

Examples of the (alkoxy) polyalkylene glycol mono (meth) acrylate include, for example, alkoxy polyalkylene glycols obtained by adding 1 to 25 moles of an alkylene oxide group having 2 to 18 carbon atoms to alcohols, particularly alkoxy polyoxyethylene mainly composed of ethylene oxide. An esterified product of an alkylene glycol and (meth) acrylic acid is preferred.
Examples of the alcohols include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 1-hexanol, and 2-hexanol. C1-C30 aliphatic alcohols such as 3-hexanol, octanol, 2-ethyl-1-hexanol, nonyl alcohol, lauryl alcohol, cetyl alcohol and stearyl alcohol; C3-C30 fats such as cyclohexanol Cyclic alcohols; unsaturated alcohols having 3 to 30 carbon atoms such as (meth) allyl alcohol, 3-buten-1-ol, 3-methyl-3-buten-1-ol, and the like.

Specifically, the following (alkoxy) polyethylene glycol (poly) (C2-C4 alkylene glycol) (meth) acrylic acid esters and the like are preferable as the esterified product.
Methoxy polyethylene glycol mono (meth) acrylate, methoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, methoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, methoxy {polyethylene glycol (poly) propylene glycol (Poly) butylene glycol} mono (meth) acrylate, ethoxypolyethyleneglycol mono (meth) acrylate, ethoxy {polyethyleneglycol (poly) propyleneglycol} mono (meth) acrylate, ethoxy {polyethyleneglycol (poly) butyleneglycol} mono (meta ) Acrylate, ethoxy {polyethylene glycol (poly) propylene glycol (poly) butylene glycol} mono (Meth) acrylate, propoxy polyethylene glycol mono (meth) acrylate, propoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, propoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, propoxy {polyethylene glycol ( Poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate,

Butoxy polyethylene glycol mono (meth) acrylate, butoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, butoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, butoxy {polyethylene glycol (poly) propylene glycol (Poly) butylene glycol} mono (meth) acrylate, pentoxypolyethylene glycol mono (meth) acrylate, pentoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, pentoxy {polyethylene glycol (poly) butylene glycol} mono ( Meth) acrylate, pentoxy {polyethylene glycol (poly) propylene glycol (poly) butylene glycol } Mono (meth) acrylate, hexoxypolyethylene glycol mono (meth) acrylate, hexoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, hexoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, hexoxy {Polyethylene glycol (poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate,

Heptoxy polyethylene glycol mono (meth) acrylate, heptoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, heptoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, heptoxy {polyethylene glycol (poly) propylene Glycol (poly) butylene glycol} mono (meth) acrylate, octoxypolyethylene glycol mono (meth) acrylate, octoxy {polyethyleneglycol (poly) propyleneglycol} mono (meth) acrylate, octoxy {polyethyleneglycol (poly) butyleneglycol} mono (Meth) acrylate, octoxy {polyethylene glycol (poly) propylene glycol (poly) butylene Recall} mono (meth) acrylate, nonanoxy polyethylene glycol mono (meth) acrylate, nonanoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, nonanoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, Nonanoxy {polyethylene glycol (poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate.

The unsaturated monomer composition used to obtain the copolymer (A) may also include other copolymerizable monomers other than the monomers (a1) and (b1) described above ( Hereinafter, it may also be referred to as “monomer (c)”.
When the monomer (c) is used, the content thereof is 100% by mass of all monomer components (unsaturated monomer compositions) used to produce the copolymer (A). On the other hand, it is suitable that it is 30 mass% or less. More preferably, it is 25 mass% or less, More preferably, it is 20 mass% or less.

Specific examples of the monomer (c) include the following compounds, and one or more of these can be used.
Half esters and diesters of unsaturated dicarboxylic acid monomers such as maleic acid, maleic anhydride, fumaric acid, itaconic acid, citraconic acid and the like and alcohols having 23 to 30 carbon atoms; Half amides and diamides of an alkyl group and an amine having 23 to 30 carbon atoms; 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 above unsaturated Half esters and diesters with dicarboxylic acid monomers; half of the above unsaturated dicarboxylic acid monomers and glycols having 5 to 18 carbon atoms or polyalkylene glycols having 2 to 500 addition moles of these glycols Esters, diesters; maleamic acid and glycols having 5 to 18 carbon atoms, or Half amides of polyalkylene glycols of addition mole number 2 to 500 of glycol;

(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; triethylene glycol dimaleate, polyethylene glycol (Poly) alkylene glycol dimaleates such as dimaleate; vinyl sulfonate, (meth) allyl sulfonate, 2- (meth) acryloxyethyl sulfonate, 3- (meth) acrylate Xylpropyl sulfonate, 3- (meth) acryloxy-2-hydroxypropyl sulfonate, 3- (meth) acryloxy-2-hydroxypropylsulfophenyl ether, 3- (meth) acryloxy-2-hydroxypropyloxysulfobenzoate, 4- ( Unsaturated sulfonic acids such as (meth) acryloxybutyl sulfonate, (meth) acrylamide methyl sulfonic acid, (meth) acrylamide ethyl sulfonic acid, 2-methylpropane sulfonic acid (meth) acrylamide, styrene sulfonic acid, and monovalents thereof Metal salts, divalent metal salts, ammonium salts and organic amine salts;

Amides of unsaturated monocarboxylic acids and amines having 1 to 30 carbon atoms such as methyl (meth) acrylamide; vinyl aromatics such as styrene, α-methylstyrene, vinyltoluene, p-methylstyrene; Alkanediol mono (meth) acrylates such as 4-butanediol mono (meth) acrylate, 1,5-pentanediol mono (meth) acrylate, 1,6-hexanediol mono (meth) acrylate; butadiene, isoprene, 2- Dienes such as methyl-1,3-butadiene and 2-chloro-1,3-butadiene; (meth) acrylamide, (meth) acrylalkylamide, N-methylol (meth) acrylamide, N, N-dimethyl (meth) Unsaturated amides such as acrylamide; (meth) acrylonitrile, α-chloroa Unsaturated cyanides such as acrylonitrile; unsaturated esters such as vinyl acetate and vinyl propionate.

Here, when the copolymer (A) is used as a concrete admixture, it is often used as an aqueous solution. Therefore, the copolymer (A) is economically produced in an aqueous solution. Is preferable. Therefore, it is preferable that the unsaturated monomer composition is mainly composed of a water-soluble monomer. “Main component” means comprising 92% by mass or more of a water-soluble monomer with respect to 100% by mass of the unsaturated monomer composition. If the ratio of the water-soluble monomer is small, the composition of the copolymer may not be sufficiently uniform due to separation from the aqueous phase during production, and an unnecessary gel is likely to be formed. There is a possibility that the performance, particularly the viscosity, the condition of the concrete, etc. cannot be improved. In addition, due to the formation of gel, the filtration process of the resulting aqueous copolymer solution takes a long time, or the gel adheres to the reaction kettle or transfer pipe, resulting in excessive time and cost for cleaning and transfer. May be economically inconvenient. The proportion of the water-soluble monomer with respect to 100% by mass of the unsaturated monomer composition is preferably 95% by mass or more, more preferably 100% by mass, that is, only the water-soluble monomer. Is Rukoto.
In addition, as a particularly preferable form of the copolymer (A), the unsaturated carboxylic acid monomer (a1) represented by the general formula (1) and the unsaturated carboxylic acid monomer represented by the general formula (2) are used. The saturated polyalkylene glycol monomer (b1) is a water-soluble monomer, that is, the copolymer (A) is a water-soluble monomer (a1) and a monomer. It is a form which is a binary copolymer composed of the monomer (b1).

The water solubility of the monomer may be such that a necessary amount of the unsaturated monomer is dissolved without being separated into water. For example, a 10% by mass aqueous solution of the unsaturated monomer is homogeneous at 20 ° C. It is suitable that it is such that it does not separate for 24 hours under the same conditions.
In addition, for example, it can be specified by a hydrophilic-lipophilic balance (HLB) value of griffin. In this case, the water-soluble monomer has a side chain portion ((alkoxy) polyalkylene glycol chain). It is preferable that the HLB value is 13 or more. More preferably, it is 15 or more, More preferably, it is 18 or more.

The HLB value of the griffin can be obtained by the following formula, for example.
HLB = (molecular weight of hydrophilic group) / (total molecular weight) × 100/5 = (mass% of hydrophilic group) / 5
In the above formula, the alkyl group is a hydrophobic group, and ethylene oxide (CH ₂ CH ₂ O (molecular weight 44)) is calculated as a hydrophilic group. In the case of a propylene oxide chain (CH (CH ₃ ) CH ₂ O), the methyl group is a hydrophobic group and the rest is a hydrophilic group (not determined for Griffin's HLB).

When determining the HLB value of the monomer component, it applies to a portion that can be a side chain of the copolymer when polymerized using the monomer (however, the carboxylic acid and the ester portion (COO ) Is excluded.) The side chain means that when the monomer is represented by “X- (side chain)”, X is, for example, C═C—COO, C═C—C—C, C═C—C or the like. Side chain part. That is, in the case of a monomer represented by “CH ₂ ═CH (CH ₃ ) COO— (AO) n—R”, the side chain portion is “(AO) nR”.
For example, it is calculated as follows.
In the case of methyl methacrylate (MMA), the side chain is a methyl group and the HLB value is zero.
In the case of methoxypolyethylene glycol monomethacrylate (average added mole number of ethylene oxide 10), the side chain is a part of methoxypolyethylene glycol (methoxyPEG), and the HLB value is calculated as follows.
HLB = (44 × 10) / (15 + 44 × 10) × 100/5 = 19.34

Next, the manufacturing method of the copolymer (A) in this invention is demonstrated.
As said manufacturing method, it can carry out by methods, such as superposition | polymerization in a solvent, and block polymerization, using the said unsaturated monomer composition and a polymerization initiator, for example.
The solution polymerization can be performed batchwise, continuously, or a combination thereof. Examples of the solvent used in this case include water; alcohols such as methyl alcohol, ethyl alcohol, and isopropyl alcohol; benzene, toluene, Aromatic or aliphatic hydrocarbons such as xylene, cyclohexane and n-hexane; ester compounds such as ethyl acetate; ketone compounds such as acetone and methyl ethyl ketone; cyclic ether compounds such as tetrahydrofuran and dioxane.
In particular, as described above, when used in a concrete admixture, it is often used as an aqueous solution, so that it is preferable to polymerize by an aqueous solution polymerization method. Thus, after the said copolymer (A) is obtained by aqueous solution polymerization method, the manufacturing method of the concrete admixture including the process of mixing with the polyamine polyalkylene oxide adduct mentioned later is also suitable embodiment of this invention. It is one of.

Among the above solution polymerizations, in aqueous solution polymerization, as a radical polymerization initiator, a water-soluble polymerization initiator, for example, a persulfate such as ammonium persulfate, sodium persulfate, or potassium persulfate; hydrogen peroxide; 2,2′- Azoamidine compounds such as azobis-2-methylpropionamidine hydrochloride, cyclic azoamidine compounds such as 2,2′-azobis-2- (2-imidazolin-2-yl) propane hydrochloride, 2-carbamoylazoisobutyronitrile, etc. Water-soluble azo initiators such as azonitrile compounds are used. In this case, alkali metal sulfites such as sodium hydrogen sulfite, metabisulfites, sodium hypophosphite, Fe (II) salts such as molle salts, hydroxy Sodium methanesulfinate dihydrate, hydroxylamine hydrochloride, thiourea, L-ascorbic acid (salt), Accelerator such as Risorubin acid (salt) (reducing agent) can be used in combination. Among them, a combination of hydrogen peroxide and an organic reducing agent is preferable. As the organic reducing agent, L-ascorbic acid (salt), L-ascorbic acid ester, erythorbic acid (salt), erythorbic acid ester, and the like are preferable. Can be used. These radical polymerization initiators and accelerators (reducing agents) may be used alone or in combination of two or more.

In solution polymerization or bulk polymerization using a lower alcohol, aromatic or aliphatic hydrocarbon, ester compound, or ketone compound as a solvent, radical polymerization initiators such as benzoyl peroxide, lauroyl peroxide, sodium peroxide, etc. Peroxides; hydroperoxides such as t-butyl hydroperoxide and cumene hydroperoxide; azo compounds such as azobisisobutyronitrile can be used. In this case, an accelerator such as an amine compound is used in combination. It is also suitable.
Further, when a water-lower alcohol mixed solvent is used, it can be appropriately selected from the above-mentioned various radical polymerization initiators or a combination of radical polymerization initiators and accelerators.

In the above copolymerization, the polymerization conditions such as the polymerization temperature are appropriately determined depending on the polymerization method used, the solvent, the polymerization initiator, and the chain transfer agent, but the polymerization temperature is preferably 0 ° C. or higher, It is preferable that it is 150 degrees C or less. More preferably, it is 30 degreeC or more, More preferably, it is 50 degreeC or more. More preferably, it is 120 degrees C or less, More preferably, it is 100 degrees C or less. In particular, in order to bring the copolymer (A) into a predetermined molecular weight or molecular weight distribution range, it is preferably 80 ° C. or lower, more preferably 70 ° C. or lower, and further preferably 60 ° C. or lower.

In the copolymerization, in order to obtain a copolymer having a predetermined molecular weight with good reproducibility, it is preferable to allow the polymerization reaction to proceed stably. Therefore, in the solution polymerization, the dissolved oxygen concentration at 25 ° C. of the solvent to be used is set to a range of 5 ppm or less (preferably 0.01 to 4 ppm, more preferably 0.01 to 2 ppm, still more preferably 0.01 to 1 ppm). It is preferable to do. In addition, when nitrogen substitution etc. are performed after adding an unsaturated monomer to a solvent, it is appropriate that the dissolved oxygen concentration of the system including the unsaturated monomer is within the above range.

The dissolved oxygen concentration of the solvent may be adjusted in a polymerization reaction tank, or a dissolved oxygen amount may be adjusted in advance. Examples of the method for driving off oxygen in the solvent include the following methods (1) to (5).
(1) After pressure-filling an inert gas such as nitrogen in a sealed container containing a solvent, the partial pressure of oxygen in the solvent is lowered by lowering the pressure in the sealed container. In that case, you may reduce the pressure in a sealed container under nitrogen stream.
(2) The liquid phase portion is vigorously stirred for a long time while the gas phase portion in the container containing the solvent is replaced with an inert gas such as nitrogen.
(3) An inert gas such as nitrogen is bubbled in the solvent in the container for a long time.
(4) The solvent is once boiled and then cooled in an inert gas atmosphere such as nitrogen.
(5) A static mixer (static mixer) is installed in the middle of the pipe, and an inert gas such as nitrogen is mixed in the pipe for transferring the solvent to the polymerization reaction tank.

The copolymer (A) obtained by the above copolymerization is adjusted to a pH range of slightly acidic or higher (more preferably pH 4 or higher, more preferably pH 5 or higher, particularly preferably pH 6 or higher) in an aqueous solution state. It can be easy to handle.
On the other hand, if the copolymerization reaction is carried out at a pH of 7 or more, the polymerization rate decreases, and at the same time, the copolymerizability is not sufficient, and the dispersion performance of the copolymer (A) may not be excellent. There is. Therefore, in the copolymerization reaction, it is preferable to perform the copolymerization reaction in a pH range from acidic to neutral (more preferably less than pH 6, more preferably less than pH 5.5, and still more preferably less than pH 5). Examples of preferable polymerization initiators that change the polymerization system from acidic to neutral include persulfates such as ammonium persulfate, sodium persulfate, and potassium persulfate, and azoamidine compounds such as azobis-2-methylpropionamidine hydrochloride. It is preferable to use a water-soluble azo initiator such as hydrogen peroxide, a combination of hydrogen peroxide and an organic reducing agent, or the like.

Therefore, after carrying out the copolymerization reaction at a low pH, it is preferable to adjust to a higher pH by adding an alkaline substance or the like. Specifically, a method of adjusting the pH to 6 or more by adding an alkaline substance after carrying out a copolymerization reaction at a pH of less than 6; a method of adjusting to a pH of 5 or more by adding an alkaline substance after carrying out a copolymerization reaction at a pH of less than 5 A method of adjusting the pH to 6 or more by adding an alkaline substance after carrying out the copolymerization reaction at a pH of less than 5;
The pH can be adjusted using, for example, an alkaline substance such as inorganic salt such as hydroxide or carbonate of monovalent metal or divalent metal; ammonia; organic amine; In addition, when pH is lowered, particularly when pH adjustment is required during polymerization, acidic substances such as phosphoric acid, sulfuric acid, nitric acid, alkylphosphoric acid, alkylsulfuric acid, alkylsulfonic acid, (alkyl) benzenesulfonic acid are used. Among these acidic substances, phosphoric acid and sulfuric acid capable of lowering the pH with addition of a small amount are preferable among these acidic substances. Further, after the reaction is completed, the concentration can be adjusted as necessary.

As a method for producing the copolymer (A), in order to produce the copolymer (A) having the “homogeneous molecular weight distribution” as described above, a factor affecting the molecular weight distribution is determined during production. It is preferable to keep within the range. In particular, since the influence of polymerization temperature, initiator, and chain transfer agent is large, it is preferable to keep them as constant as possible.
Specifically, the change in polymerization temperature during the production process is preferably ± 10 ° C, more preferably ± 5 ° C. However, immediately after the start of the polymerization reaction, the temperature is likely to change temporarily due to the addition of a monomer or an initiator, so this is not the case.
Further, during the production process, the initiator is preferably added to the reaction system at a constant rate. When using a relatively high thermal stability initiator such as hydrogen peroxide in the redox system, the initiator and the reducing agent may be added to the reaction system at a constant rate. The reducing agent may be added at a constant rate.
Further, during the production process, it is preferable not to use a chain transfer agent or to add it at a constant rate in the reaction system.
As the production method, it is preferable that the semi-batch method and the stirred tank type continuous method are mainly used rather than the batch method and the tube-type continuous method from the viewpoint of suppressing the concentration change during the production.
The above conditions are not limited to this because the influence on the molecular weight distribution is small in the aging step after the polymerization reaction is almost completed.

Next, the polyamine polyalkylene oxide adduct (C), which is an essential component of the concrete admixture copolymer composition of the present invention, will be described.
The polyamine polyalkylene oxide adduct (C) (hereinafter also referred to as “compound (C)”) is a compound obtained by adding alkylene oxide to an active hydrogen atom on a nitrogen atom of a polyamine compound. In particular, a compound obtained by adding an alkylene oxide having 2 to 8 carbon atoms to an active hydrogen atom on a nitrogen atom of a polyamine compound containing 3 or more nitrogen atoms in one molecule is preferable.

The polyamine compound may be a compound having two or more amino groups and / or imino groups in one molecule. For example, methylamine, ethylamine, propylamine, butylamine, 2-ethylbutylamine, octylamine, dimethylamine , Dipropylamine, dimethylethanolamine, dibutylamine, trimethylamine, triethylamine, cyclobutylamine, cyclohexylamine, alkylamines such as laurylamine; alkyleneamines such as allylamine; aromatic amines such as aniline and diphenylamine; ammonia, urea, thiourea Homopolymers and copolymers obtained by polymerizing one or more monoamine compounds such as nitrogen compounds, etc. by a conventional method: ethyleneimine, propyleneimine, 1,2-butyleneimine, 2,3 Butylene imine, 1,1-dimethylethylene imine one or solely of two or more obtained by polymerization in a conventional manner a polymer or copolymer of alkylene imine having 2 to 8 carbon atoms such as and the like. In these, a polyamine chain (or polyalkyleneimine chain) is formed, and the chain has any of a linear structure, a branched structure, and a three-dimensionally crosslinked structure. May be. Further, ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, dipropylenetriamine, tripropylenetetramine, tetrapropylenepentamine and the like may be used. Polyalkyleneimines are three-dimensionally crosslinked by polymerization, and usually have a primary amino group or secondary amino group (imino group) having an active hydrogen atom in addition to a tertiary amino group in the structure. become.

Among the polyamine compounds, polyalkylamines and polyalkyleneimines are preferably used. As the alkylamines constituting the polyalkylamines, alkylamines having 8 to 18 carbon atoms such as laurylamine are preferable. As the alkyleneimine that constitutes, an alkyleneimine having 2 to 8 carbon atoms is preferred. More preferred is a polyalkyleneimine, and particularly preferred is a polyalkyleneimine mainly composed of ethyleneimine.

The “main body” in this case means that when the polyalkyleneimine is formed by two or more kinds of alkyleneimines, it accounts for the majority of the total number of alkyleneimines present. In the present invention, the alkyleneimine that forms a polyalkyleneimine chain is mainly composed of ethyleneimine, so that the hydrophilicity of the compound (C) is improved and the effects are sufficiently exerted. When ethyleneimine is used as an alkyleneimine that forms a polyalkyleneimine chain to such an extent that the above-mentioned effects are sufficiently exerted, the above-mentioned “occupies the majority”. When “dominating” is expressed in terms of mol% of ethyleneimine in 100 mol% of all alkyleneimines, it is preferably 50 to 100 mol%. If it is less than 50 mol%, the hydrophilicity of the polyalkyleneimine chain may not be sufficient. More preferably, it is 60 mol% or more, More preferably, it is 70 mol% or more, Especially preferably, it is 80 mol% or more, Most preferably, it is 90 mol% or more.

The average polymerization number of the alkyleneimine per one polyalkyleneimine chain is preferably 2 or more, and preferably 300 or less. If it is out of such a range, the action and effect attributable to the compound (C) may not be sufficiently exhibited. As a lower limit, More preferably, it is 3, More preferably, it is 5, Especially preferably, it is 10. Moreover, as an upper limit, More preferably, it is 200, More preferably, it is 100, Especially preferably, it is 50, Most preferably, it is 25. The average polymerization number of diethylenetriamine is 2, and the average polymerization number of triethylenetetramine is 3.

As a number average molecular weight of the said polyamine compound, 100-100000 are preferable, More preferably, it is 300-50000, More preferably, it is 600-10000, Most preferably, it is 800-5000.

The alkylene oxide may be any alkylene oxide having 2 or more carbon atoms (polyalkylene oxide), and the alkylene oxide is preferably an alkylene oxide having 2 to 18 carbon atoms. More preferably, it is an alkylene oxide having 2 to 8 carbon atoms, such as ethylene oxide, propylene oxide, butylene oxide, isobutylene oxide, 1-butene oxide, 2-butene oxide, trimethylethylene oxide, tetramethylene oxide, tetramethylethylene oxide, butadiene. Examples include monooxide and octylene oxide. In addition, aliphatic epoxides such as dipentane ethylene oxide and dihexane ethylene oxide; alicyclic epoxides such as trimethylene oxide, tetramethylene oxide, tetrahydrofuran, tetrahydropyran, and octylene oxide; aromatics such as styrene oxide and 1,1-diphenylethylene oxide Epoxides and the like can also be used.
Among these, ethylene oxide, propylene oxide, and butylene oxide are preferable, and those mainly composed of ethylene oxide are particularly preferable.

The “main body” as used herein means that when the polyalkylene oxide is composed of two or more kinds of alkylene oxides, it accounts for the majority of the total number of alkylene oxides present. When “dominating” is expressed in terms of mol% of ethylene oxide in 100 mol% of all alkylene oxides, 50 to 100 mol% is preferable. If it is less than 50 mol%, the hydrophilicity of the group formed from the alkylene oxide may not be sufficient. More preferably, it is 60 mol% or more, More preferably, it is 70 mol% or more, Especially preferably, it is 80 mol% or more, Most preferably, it is 90 mol% or more.

When the polyalkylene oxide is composed of two or more alkylene oxides, two or more alkylene oxides may be added in any form of random addition, block addition, alternating addition, etc. When a plurality of the polyalkylene oxides are present in one molecule of the compound (C), these may be the same or different.

The average number of added moles of the alkylene oxide to the polyamine compound is preferably more than 0 and 300 or less. If it is out of such a range, there is a possibility that the effect of making the fluidity of the cement composition etc. excellent will not be sufficiently exhibited. As a lower limit, More preferably, it is 3, More preferably, it is 5, Especially preferably, it is 10, Most preferably, it is 20. Moreover, as an upper limit, More preferably, it is 200, More preferably, it is 150, More preferably, it is 100, Especially preferably, it is 75, Most preferably, it is 50.
The average added mole number means the average value of the number of moles of alkylene oxide added in 1 mole of the polyalkylene oxide of the compound (C) or the compound (C). It means the average value of the number of moles of alkylene oxide added per mole of hydrogen atom (active hydrogen atom) on the nitrogen atom of the polyamine compound.

As a method for adding alkylene oxide to the polyamine compound, polymerization can be carried out by a usual method, and a method using an acid catalyst or an alkali catalyst is suitable. As the acid catalyst, metal and metalloid halogen compounds that are Lewis acid catalysts such as boron trifluoride; mineral acids such as hydrogen chloride, hydrogen bromide, and sulfuric acid are suitable. As the alkali catalyst, potassium hydroxide, Sodium hydroxide and sodium hydride are preferred.

In the polyamine polyalkylene oxide adduct (C), the end of the alkylene oxide (oxyalkylene group) not bonded to the amine residue (or imine residue) of the polyamine compound is, for example, a hydrogen atom or a monovalent metal. Atom, divalent metal atom, ammonium group, organic amine group, hydrocarbon group having 1 to 30 carbon atoms, oxo hydrocarbon group, amide hydrocarbon group, carboxyl hydrocarbon group, sulfonyl group having 0 to 30 carbon atoms (hydrocarbon) It is preferable to have a structure bonded to any of the groups, and when two or more oxyalkylene groups are present in one molecule, the terminal structures may be the same or different. Among such terminal structures, from the viewpoint of versatility, it is bonded to a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, preferably a hydrogen atom or a carbon hydrogen group having 1 to 10 carbon atoms, to an alkyl group or an alkylene group. It is preferable that it is the structure.

Specific examples of the polyamine polyalkylene oxide adduct (C) include, for example, a compound (C-1) obtained by adding alkylene imine to both ends of polyalkylene oxide, an alkylene imine graft product of polyalkylene oxide ( C-2), at least one compound selected from the group consisting of amine alkylene oxide adduct (C-3) and polyalkyleneimine alkylene oxide adduct (C-4) is preferable. Alkylene oxide adducts (C-4) are particularly preferred.

As the compound (C-1) obtained by adding an alkyleneimine to both ends of the polyalkylene oxide, carbon atoms are added to hydroxyl groups at both ends of one or more polymers of alkylene oxide having 2 to 18 carbon atoms. It is preferable that it is a compound obtained by superposing | polymerizing 1 type (s) or 2 or more types of the alkyleneimine (preferably what mainly has ethyleneimine) of 2-8.

As the alkyleneimine graft product (C-2) of the above polyalkylene oxide, 1 type of alkyleneimine having 2 to 8 carbon atoms can be added to methylene hydrogen of one or more polymers having 2 to 18 carbon atoms. It is preferable that it is a compound obtained by graft-polymerizing seed | species or 2 or more types.

The amine alkylene oxide adduct (C-3) may be a compound having a structure in which an oxyalkylene group is bonded to an amine residue. Among them, the amine residue is preferably an alkylamine residue. . That is, the amine alkylene oxide adduct (C-3) is preferably an alkylamine alkylene oxide adduct.
The amine residue means a group having a structure excluding a hydrogen atom (active hydrogen atom) on the nitrogen atom of the amine, but is not particularly limited to a group formed by reaction with an amine, In addition, the amine residue is preferably composed of three elements of carbon, hydrogen, and nitrogen.
As a number average molecular weight of the said amine alkylene oxide adduct (C-3), it is preferable that it is 300 or more, and it is preferable that it is 50000 or less. As a lower limit, More preferably, it is 400, More preferably, it is 500. Moreover, as an upper limit, More preferably, it is 30000, More preferably, it is 10,000, Most preferably, it is 5000.

The polyalkyleneimine alkylene oxide adduct (C-4) may be any polyalkyleneimine having an oxyalkylene group, and is obtained by adding alkylene oxide to the nitrogen atom of the amino group or imino group of the polyalkyleneimine. Are preferred.
The number average molecular weight of the polyalkyleneimine alkylene oxide adduct (C-4) is preferably 1000 or more and more preferably 50000 or less. As a lower limit, More preferably, it is 2000, More preferably, it is 5000, Especially preferably, it is 10,000. Moreover, as an upper limit, More preferably, it is 30000, More preferably, it is 20000, Most preferably, it is 15000.

In the copolymer composition for a concrete admixture of the present invention, the proportion of the polyamine polyalkylene oxide adduct (C) used is a mass ratio of the total amount of the copolymer and the compound (C) (of the copolymer). It is preferable to set the total amount / compound (C)) to be 95/5 to 5/95. The mass ratio is more preferably 90/10 to 10/90, still more preferably 80/20 to 20/80, and particularly preferably 70/30 to 30/70.
Here, the “total amount of copolymer” means the sum when two or more types of copolymers are included. For example, when two or more types of copolymers (A) are used, the total amount When the copolymer (A) and another copolymer (for example, the copolymer (B) described later) are used in combination, the total is the sum.

Although it does not specifically limit as a manufacturing method of the said copolymer composition for concrete admixtures, The said copolymer (A) and the said compound (C) are mixed before adding to a cement composition etc., and the said concrete The copolymer composition for admixture may be in the form in which it is manufactured, or the above-mentioned copolymer composition for concrete admixture in cement composition etc. by being added separately to cement composition etc. It may be.

The copolymer composition for a concrete admixture of the present invention preferably comprises two or more of the polycarboxylic acid copolymers (A). As a result, various performances such as fluidity, retention and workability (good viscosity) of the cement composition can be exhibited at the same time, and moreover, the effects of the present invention can be further enhanced by further improving one or more performances. Is possible.
Here, including two or more kinds of the above-mentioned copolymers (A) means that the average number of repeating alkylene glycol units and the weight average molecular weight satisfy the above ranges, and the acid value, molecular weight, molecular weight distribution, structural unit What is necessary is just to contain 2 or more types of copolymers which differ in points, such as a structure and a composition of a structural unit.
Although it does not specifically limit as a manufacturing method of the copolymer composition containing the said 2 or more types of said copolymer (A) and the said compound (C), For example, copolymer (A) is 2 It is preferable to employ a method of mixing them with the compound (C) after obtaining more than one species.

The copolymer composition for concrete admixture of the present invention preferably further comprises a polycarboxylic acid copolymer (B) different from the polycarboxylic acid copolymer (A). . In this case, 1 type (s) or 2 or more types can be used for the copolymer (A) and (B) which is a containing component, respectively.
In this way, two or more polycarboxylic acid copolymers of the copolymer (A) and a copolymer (B) different from the copolymer (A) are used in combination with the compound (C). Therefore, when used as a concrete admixture, the various properties of the polycarboxylic acid copolymer blended with the concrete admixture are combined, so that sufficient fluidity and retention required for a cement composition are obtained. In addition, various performances such as workability can be exhibited in a balanced manner.

The polycarboxylic acid copolymer (B) (hereinafter, also referred to as “copolymer (B)”) includes the copolymer (A), acid value, molecular weight, molecular weight distribution, and structural unit structure. Any of the polycarboxylic acid copolymers differing in terms of the composition of the structural units, etc., among which the numerical values specified in the copolymer (A) in terms of the average number of repeating alkylene glycol units or the weight average molecular weight. It is preferable that it does not satisfy the range.
Such a copolymer (B) is obtained by copolymerizing an unsaturated monomer composition essentially comprising an unsaturated carboxylic acid monomer and an unsaturated polyalkylene glycol monomer. It is preferable that In addition, these monomer components can use 1 type (s) or 2 or more types, respectively.

Here, the carboxylic acid group possessed by the unsaturated carboxylic acid monomer imparts water-solubility and adsorption force to inorganic fine particles such as cement to the copolymer (B). When the copolymer (B) is used as a concrete admixture in combination with the copolymer (A), in order to sufficiently develop the adsorption force to the inorganic fine particles, it contains an unsaturated carboxylic acid monomer. The amount is preferably 2.5% by mass or more with respect to 100% by mass of all the monomer components (unsaturated monomer compositions) used to produce the copolymer (B). It is. More preferably, it is 5 mass% or more, More preferably, it is 10 mass% or more, Especially preferably, it is 15 mass% or more, Most preferably, it is 20 mass%. Further, from the same viewpoint, it is preferably 40% by mass or less. More preferably, it is 35 mass% or less, More preferably, it is 30 mass% or less, Especially preferably, it is 25 mass% or less, Most preferably, it is 22.5 mass% or less.

Moreover, the polyalkylene glycol chain which the said unsaturated polyalkylene glycol-type monomer has will provide the dispersion power of inorganic fine particles, such as water solubility and cement, with respect to a copolymer (B). When the copolymer (B) is used in combination with the copolymer (A) as a concrete admixture, the content of the unsaturated polyalkylene glycol monomer should be It is preferable that the content be 60% by weight or more with respect to 100% by mass of all monomer components (unsaturated monomer compositions) used to produce the polymer (B). More preferably, it is 70 mass% or more, More preferably, it is 75 mass% or more, Especially preferably, it is 80 mass% or more, Most preferably, it is 85 mass% or more. On the other hand, if the amount of the unsaturated polyalkylene glycol monomer is too large, the amount of the unsaturated carboxylic acid monomer having an adsorptive power to cement particles becomes relatively small. The following is preferable. More preferably, it is 95 mass% or less, More preferably, it is 92.5 mass% or less, Especially preferably, it is 90 mass% or less, Most preferably, it is 87.5 mass% or less.

As a more preferable form as the copolymer (B), for example, the following general formula (3);

^(Wherein, R 8, ^{R 9} and ^{R 10} are the same or different, a hydrogen atom, a methyl group or _- represents a (CH 2) pCOOM ⁴ _{Note, -. (CH 2) pCOOM} 4 is -COOM ³ or It may form an anhydride with other — (CH ₂ ) pCOOM ^4. p is an integer of 0 to 2. M ³ and M ⁴ are the same or different and are a hydrogen atom or a monovalent metal atom. , Represents a divalent metal atom, a trivalent metal atom, a quaternary ammonium base or an organic amine base.) (Hereinafter referred to as “monomer (a2)”) And general formula (4) below;

(.AO ^wherein, R ^{11, R 12} and ^{R 13} are the same or different, ^{.R 14} represents a hydrogen atom or a methyl group, represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms are the same Or, differently, it represents one or more of oxyalkylene groups having 2 to 18 carbon atoms, and when there are two or more oxyalkylene groups represented by AO, these groups are introduced in a block form. May be introduced randomly, q is an integer of 0 to 2. r is 0 or 1. n2 represents the average number of added moles of the oxyalkylene group; The unsaturated polyalkylene glycol monomer (b2) (hereinafter also referred to as “monomer (b2)”) represented by the following formula: Is obtained by copolymerization.

In the above general formula (3), the metal atom represented by M ³ and M ⁴ is the same as M ¹ and M ² in the above general formula (1), and the single atom represented by the above general formula (3). Specific examples of the monomer (a2) are also the same as those of the monomer (a1) represented by the general formula (1).

In the general formula (4), the group represented by R ¹⁴ and the polyalkylene glycol chain represented by (AO) _n2 are also represented by the group represented by R ⁷ and (AO) n1 in the general formula (2). The specific example of the monomer (b2) represented by the general formula (4) is also the same as the polyalkylene glycol chain represented by the general formula (4). ).

N2 in the above general formula (4) is a number from 1 to 300, but if it exceeds 300, problems in production occur or the viscosity of the cement composition becomes high when used as a concrete admixture, May not be sufficient. From the viewpoint of production, n2 is suitably 300 or less, preferably 200 or less, more preferably 150 or less, still more preferably 100 or less, particularly preferably 75 or less, and most preferably 50. It is as follows. Further, n2 is preferably 4 or more from the viewpoint of strongly dispersing cement particles. More preferably, it is 6 or more, More preferably, it is 10 or more, Most preferably, it is 25 or more.

The unsaturated monomer composition used to obtain the copolymer (B) may also include other copolymerizable monomers other than the monomers (a2) and (b3) described above ( Hereinafter, it may be also referred to as “monomer (c2)”), and specific examples thereof are the same as those of the monomer (c1) in the copolymer (A).
As content of such a monomer (c2), 100 mass% of all monomer components (unsaturated monomer compositions) used to produce the copolymer (B). 30% by mass or less is preferable. More preferably, it is 25 mass% or less, More preferably, it is 20 mass% or less.

The copolymer (B) preferably has a weight average molecular weight (Mw) of 150,000 or less. If the Mw exceeds 150,000, the retainability and viscosity of the cement composition may not be improved. Preferably it is 100,000 or less, more preferably 70,000 or less, still more preferably 60,000 or less, even more preferably 50,000 or less, particularly preferably 40,000 or less, most preferably 30,000. It is as follows. Moreover, it is preferable that Mw is 10,000 or more from the viewpoint that the copolymer (B) is more likely to exhibit performance when adsorbed to cement particles to some extent, and that the adsorbing force increases as Mw increases. More preferably, it is 15000 or more, More preferably, it is 18000 or more, Most preferably, it is 20,000 or more.

In the copolymer (B), if the weight average molecular weight / number average molecular weight (Mw / Mn) of the copolymer (B) is too large, the dispersion performance may be affected. It is preferable that it is 4 or less. More preferably, it is 3.5 or less, More preferably, it is 3 or less, Especially preferably, it is 2.5 or less, Most preferably, it is 2.2 or less.

The copolymer (B) further has the following formula:
An value = A value × 100 × n
(In the formula, the value A is the total mass of all monomer components when the carboxylic acid groups in the charged monomer are all sodium salts during the production of the polycarboxylic acid copolymer (B). This represents the mass ratio (mass%) of the sodium carboxylate-containing monomer with respect to 100 mass%, where n is the average number of alkylene glycol unit repeats of the polyalkylene glycol chain of the polycarboxylic acid copolymer (B). In addition, it is preferable that the An value represented by the An value is rounded to an integer by rounding off the decimal point.
An example of such a polymer that satisfies the An value is a copolymer of 363.5 parts by weight of methoxypolyethylene glycol methacrylate (n = 10) and 96.5 parts by weight of methacrylic acid (Mw 86.09). In this case, assuming that methacrylic acid is a sodium salt, sodium methacrylate (Mw 108.07) corresponds to 121.1 parts by weight, and the A value is 121.1 / (363.5 + 121). .1) = 25%. Therefore, An value = 25% × 100 × 10 = 250.

The An value of the copolymer (B) indicates the balance between the amount of carboxylic acid groups that are adsorbing groups on the cement particles and the length of the polyalkylene glycol chain in which cement and particles are dispersed. When the An value of the copolymer (B) is too small, sufficient performance may not be exhibited when used as a concrete admixture with the copolymer (A). Is preferably 230 or more. More preferably, it is 250 or more, More preferably, it is 300 or more, Most preferably, it is 400 or more. On the other hand, when the An value of the copolymer (B) is too large, sufficient performance may not be exhibited when used as a concrete admixture with the copolymer (A). is there. More preferably, it is 1500 or less, More preferably, it is 1000 or less, Especially preferably, it is 750 or less, Most preferably, it is 500 or less.

In the present invention, it is particularly preferable that the copolymer (B) has a weight average molecular weight (Mw) of 10,000 or more and an An value of 230 or more. By using such a copolymer (B) together with the copolymer (A), it becomes possible to impart sufficient fluidity, retention and viscosity to the cement composition.
In addition, as a manufacturing method of the said copolymer (B), it can carry out similarly to the said copolymer (A). Further, as described above with respect to the copolymer (A), also in the production method of the copolymer (B), a mixture of two or more kinds of copolymers can be obtained by changing the conditions of the polymerization reaction. The above copolymer can be mixed to make a blend mixture. Even in such a case, the weight average molecular weight of the copolymer mixture can be measured, or the alkylene glycol in the polyalkylene glycol chain can be measured. Even if the number of repeating units is measured or calculated, it can be evaluated that it falls under the copolymer (B) of the present invention even when specified as described above.

In the copolymer composition, the mass ratio (A / B) between the copolymer (A) and the copolymer (B) is preferably 5/95 to 95/5, more preferably. Is 20/80 to 80/20. More preferably, the proportion of the copolymer (A) is 30% by mass or more with respect to 100% by mass of the total amount of the copolymer composition for concrete admixture. In addition, the function and effect of the present invention can be more sufficiently exhibited at the same time with high workability. More preferably, it is 40 mass% or more, and is 30-70 mass% as a suitable range.
Although it does not specifically limit as a manufacturing method of the copolymer composition which further contains the said copolymer (B), For example, after obtaining a copolymer (A) and a copolymer (B), respectively, these and said compound It is preferable to employ a method of mixing (C).

The copolymer composition for concrete admixture of the present invention is suitable as a main component of the concrete admixture, and the concrete admixture comprising the above-mentioned copolymer composition for concrete admixture is also the present invention. It is one of.
Furthermore, the concrete admixture can be used in addition to a cement composition such as cement paste, mortar, concrete, and the like. A cement composition comprising the concrete admixture as described above is also one aspect of the present invention. is there.

As the above-mentioned cement composition, those containing cement, water, fine aggregate, coarse aggregate and the like are suitable. As the cement, Portland cement (ordinary, early strength, very early strength, moderate heat, sulfate resistance, 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, high content of belite); ultra high strength cement; cement-based solidified material; ecocement (city waste) Cement produced from one or more of incineration ash and sewage sludge incineration ash G) other such, these blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica fume, silica powder, and a film obtained by adding a fine powder and gypsum limestone powder.
As the above aggregate, in addition to gravel, crushed stone, granulated slag, recycled aggregate, etc., siliceous, clay, zircon, high alumina, silicon carbide, graphite, chrome, chromic, magnesia, etc. Refractory aggregate and the like.

Examples of the unit water amount per 1 m ³ of the cement composition, the cement use amount, and the water / cement ratio (mass ratio) include, for example, a unit water amount of 100 to 185 kg / m ³ , a use cement amount of 200 to 800 kg / m ³ , and a water / cement ratio. The cement ratio (mass ratio) is preferably 0.1 to 0.7, and more preferably, the unit water amount is 120 to 175 kg / m ³ , the cement amount used is 250 to 800 kg / m ³ , and the water / cement ratio ( (Mass ratio) = 0.2 to 0.65. Thus, the concrete admixture containing the copolymer (A) or copolymer composition of the present invention can be used in a wide range from poor blending to rich blending, and has a high water reduction rate range, that is, It can be used even in a region where the water / cement ratio is low, such as water / cement ratio (mass ratio) = 0.15 to 0.5 (preferably 0.15 to 0.4). It is effective for both high-strength concrete with a small cement ratio and poor blended concrete with a unit cement amount of 300 kg / m ³ or less.

The concrete admixture of the present invention can exhibit fluidity, retention and workability in a well balanced and high performance even in a high water reduction rate region, and has excellent workability. Therefore, ready-mixed concrete, concrete secondary products ( It can be used effectively for concrete for precast concrete), concrete for centrifugal molding, concrete for vibration compaction, steam-cured concrete, shotcrete, etc. Furthermore, medium-fluidity concrete (slump value is 22-25cm) Mortar and concrete that require high fluidity, such as concrete with high fluidity (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, etc. Also effective.

When the above concrete admixture is used in the cement composition, as a blending ratio thereof, the copolymer (A), which is an essential component of the present invention, is calculated in terms of solid content and is 100% by mass of the total mass of cement. It is preferable to set so that it may become 0.01-10 mass%. If it is less than 0.01% by mass, the performance may not be sufficient. On the other hand, if it exceeds 10% by mass, the effect will substantially reach its peak, which may be disadvantageous in terms of economy. More preferably, it is 0.02-8 mass%, More preferably, it is 0.05-6 mass%.

The concrete admixture can also be used in combination with other cement additives. As another cement additive, 1 type (s) or 2 or more types, such as a cement additive (material) as shown below, can be used, for example. Among these, it is particularly preferable to use an oxyalkylene antifoaming agent or an AE agent in combination.
In addition, it is suitable for the addition ratio of a cement additive to be 0.0001-10 weight part with respect to 100 weight part of solid content of the said copolymer (A).

(1) Water-soluble polymer substances: polyacrylic acid (sodium), polymethacrylic acid (sodium), polymaleic acid (sodium), unsaturated carboxylic acid polymer such as sodium salt of acrylic acid / maleic acid copolymer; polyethylene Polyoxyethylene or polyoxypropylene polymers such as glycol and polypropylene glycol or copolymers thereof; Nonionic cellulose ethers such as methylcellulose, ethylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, carboxymethylcellulose, carboxyethylcellulose, hydroxypropylcellulose; yeast glucan Or xanthan gum, β-1,3 glucans (both linear and branched), for example, curdlan, paramylon, pachyman Polysaccharides produced by microbial fermentation such as scleroglucan, laminaran, etc .; polyacrylamide; polyvinyl alcohol; starch; starch phosphate ester; sodium alginate; gelatin; Grade compounds and the like.

(2) Polymer emulsion.
(3) Retardant: Gluconic acid, malic acid or citric acid, and oxycarboxylic acids such as inorganic salts or organic salts such as sodium, potassium, calcium, magnesium, ammonium, triethanolamine, and salts thereof; glucose , Fructose, galactose, saccharose; sugar alcohols such as sorbitol; magnesium silicate; phosphoric acid and its salts or borate esters; aminocarboxylic acid and its salts; alkali-soluble protein; humic acid; tannic acid; Polyhydric alcohols such as aminotri (methylenephosphonic acid), 1-hydroxyethylidene-1,1-diphosphonic acid, ethylenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta (methylenephosphonic acid) and alkali metal salts thereof, al Phosphonic acids and derivatives thereof such as Li earth metal salts.

(4) Early strengthening agent / accelerator: soluble calcium salt such as calcium chloride, calcium nitrite, calcium nitrate, calcium bromide, calcium iodide; alkanolamine; alumina cement; calcium aluminate silicate.
(5) Mineral oil-based antifoaming agent: cocoon oil, liquid paraffin, etc.
(6) Fat and oil-based antifoaming agents: animal and vegetable oils, sesame oil, castor oil, and alkylene oxide adducts thereof.
(7) Fatty acid-based antifoaming agent: oleic acid, stearic acid, and these alkylene oxide adducts.
(8) Fatty acid ester antifoaming agent: glycerin monoricinoleate, alkenyl succinic acid derivative, sorbitol monolaurate, sorbitol trioleate, natural wax and the like.

(9) Oxyalkylene antifoaming agents: polyoxyalkylenes such as (poly) oxyethylene (poly) oxypropylene adducts; diethylene glycol heptyl ether, polyoxyethylene oleyl ether, polyoxypropylene butyl ether, polyoxyethylene polyoxypropylene (Poly) oxyalkyl ethers such as 2-ethylhexyl ether and higher alcohols having 12 to 14 carbon atoms such as oxyethyleneoxypropylene adducts; (poly) oxy such as polyoxypropylene phenyl ether and polyoxyethylene nonylphenyl ether Alkylene (alkyl) aryl ethers; 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 2,5-dimethyl-3-hexyne-2,5-diol, 3-methyl-1 -Bu Acetylene ethers obtained by addition polymerization of alkylene oxide to acetylene alcohol such as n-3-ol; (poly) oxyalkylene fatty acid esters such as diethylene glycol oleate, diethylene glycol laurate, ethylene glycol distearate; polyoxyethylene (Poly) oxyalkylene sorbitan fatty acid esters such as sorbitan monolaurate and polyoxyethylene sorbitan trioleate; (poly) oxyalkylene alkyls such as sodium polyoxypropylene methyl ether sulfate and sodium polyoxyethylene dodecylphenol ether sulfate ( Aryl) ether sulfates; (poly) oxyethylene stearyl phosphates, etc. Polyoxyalkylene alkyl phosphoric acid esters; polyoxyethylene such as polyoxyethylene lauryl amine (poly) oxyalkylene alkyl amines; polyoxyalkylene amide.

(10) Alcohol-based antifoaming agent: octyl alcohol, hexadecyl alcohol, acetylene alcohol, glycols and the like.
(11) Amide antifoaming agent: acrylate polyamine and the like.
(12) Phosphate ester antifoaming agent: tributyl phosphate, sodium octyl phosphate, etc.
(13) Metal soap type antifoaming agent: aluminum stearate, calcium oleate, etc.
(14) Silicone antifoaming agent: dimethyl silicone oil, silicone paste, silicone emulsion, organically modified polysiloxane (polyorganosiloxane such as dimethylpolysiloxane), fluorosilicone oil and the like.
(15) AE agent: resin soap, saturated or unsaturated fatty acid, sodium hydroxystearate, lauryl sulfate, ABS (alkyl benzene sulfonic acid), LAS (linear alkyl benzene sulfonic acid), alkane sulfonate, polyoxyethylene alkyl (phenyl) ether , Polyoxyethylene alkyl (phenyl) ether sulfate or a salt thereof, polyoxyethylene alkyl (phenyl) ether phosphate or a salt thereof, protein material, alkenyl sulfosuccinic acid, α-olefin sulfonate, and the like.

(16) Other surfactants: aliphatic monohydric alcohols having 6 to 30 carbon atoms in the molecule such as octadecyl alcohol and stearyl alcohol, and those having 6 to 30 carbon atoms in the molecule such as abiethyl alcohol Intramolecular such as alicyclic monohydric alcohol, dodecyl mercaptan, etc. Intramolecular such as monovalent mercaptan having 6-30 carbon atoms in the molecule, such as nonylphenol, alkylphenol having 6-30 carbon atoms in the molecule, dodecylamine, etc. 10 mol or more of an alkylene oxide such as ethylene oxide or propylene oxide was added to a carboxylic acid having 6 to 30 carbon atoms in the molecule such as an amine having 6 to 30 carbon atoms, lauric acid or stearic acid. Polyalkylene oxide derivatives; having an alkyl group or alkoxyl group as a substituent Alkyl diphenyl ether sulfonates in which two phenyl groups having a sulfone group are ether-bonded; various anionic surfactants; various cationic surfactants such as alkylamine acetate and alkyltrimethylammonium chloride; various nonions Surfactants; various amphoteric surfactants.
(17) Waterproofing agent: fatty acid (salt), fatty acid ester, oil and fat, silicon, paraffin, asphalt, wax and the like.
(18) Rust inhibitor: nitrite, phosphate, zinc oxide and the like.
(19) Crack reducing agent: polyoxyalkyl ethers; alkanediols such as 2-methyl-2,4-pentanediol.
(20) Expansion material: Ettlingite, coal, etc.

Other cement additives (materials) include, for example, cement wetting agents, thickeners, separation reducing agents, flocculants, drying shrinkage reducing agents, strength enhancing agents, self-leveling agents, rust preventives, colorants, antifungal agents , Blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica fume, silica powder, gypsum and the like.

Since the copolymer composition for a concrete admixture of the present invention is configured as described above, it can impart excellent fluidity to the cement composition and can exhibit high fluidity over a long period of time. At the same time, it can be made viscous so that it is easy to work at the site where the cement composition is handled, so it is very useful as a concrete admixture.

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by weight” and “%” means “mass%”.
The weight average molecular weight (Mw), number average molecular weight (Mn), and peak top molecular weight (Mp) of the polymers obtained in the following production examples were measured under the above-described measurement conditions, and the An value was also as described above. Was calculated as follows.

Production Example 1
Into a reaction vessel equipped with a thermometer, a stirrer, a reflux device, and a dropping device, 204.8 parts by weight of water was charged, heated to 70 ° C., and purged with nitrogen at 200 ml / min for 1 hour. Thereafter, a mixed solution of 373.6 parts by weight of methoxypolyethyleneglycol methacrylate (average added mole number 10), 86.4 parts by weight of methacrylic acid, 123.5 parts by weight of water, and 15.3 parts by weight of 2-mercaptopropionic acid ( 1) for 4 hours, a mixed solution (2) of 3.8 parts by weight of 30% aqueous hydrogen peroxide and 71.2 parts by weight of water, a mixed solution of 1.5 parts by weight of L-ascorbic acid and 73.5 g of water ( 3) was continuously added dropwise to a reaction vessel maintained at 70 ° C. for 5 hours. Furthermore, the temperature was maintained at 70 ° C. for 1 hour to obtain a copolymer solution. When the solution temperature was 30 ° C., a 30% NaOH aqueous solution was added dropwise to adjust the solution pH to 7. The weight average molecular weight of the obtained copolymer was 5500, and Mw / Mn was 1.55. This copolymer is referred to as “copolymer (A1)”.

Production Example 2
A reaction vessel equipped with a thermometer, a stirrer, a reflux device and a dropping device was charged with 213.3 parts by weight of water, heated to 70 ° C., and purged with nitrogen at 200 ml / min for 1 hour. Thereafter, a mixed solution of 363.5 parts by weight of methoxypolyethyleneglycol methacrylate (average added mole number 10), 96.5 parts by weight of methacrylic acid, 123.5 parts by weight of water, and 7.6 parts by weight of 2-mercaptopropionic acid ( 1) for 4 hours, a mixed solution (2) of 4.1 parts by weight of 30% aqueous hydrogen peroxide and 70.9 parts by weight of water, a mixed solution of 1.6 parts by weight of L-ascorbic acid and 73.4 parts of water ( 3) was continuously added dropwise to a reaction vessel maintained at 70 ° C. for 5 hours. Furthermore, the temperature was maintained at 70 ° C. for 1 hour to obtain a copolymer solution. When the solution temperature was 30 ° C., a 30% NaOH aqueous solution was added dropwise to adjust the solution pH to 7. The weight average molecular weight of the obtained copolymer was 8200, and Mw / Mn was 1.67. This copolymer is referred to as “copolymer (A2)”.

Production Example 3
A reaction vessel equipped with a thermometer, a stirrer, a reflux device and a dropping device was charged with 350.0 parts by weight of water, heated to 70 ° C., and purged with nitrogen at 200 ml / min for 1 hour. Then, 373.6 parts by weight of methacrylic acid ester of H- (OC ₂ H ₄ ) _3- (OC ₃ H ₆ )-(OC ₂ H ₄ ) ₆ -OCH ₃ , 74.4 parts by weight of methacrylic acid, water 112. 1 part by weight and a mixed solution (1) of 9.09 parts by weight of 2-mercaptopropionic acid over 4 hours, a mixed solution of 3.5 parts by weight of 30% aqueous hydrogen peroxide and 31.5 parts by weight of water (2 ), A mixed solution (3) of 1.3 parts by weight of L-ascorbic acid and 29.0 of water was continuously added dropwise to a reaction vessel kept at 70 ° C. for 5 hours. Furthermore, the temperature was maintained at 70 ° C. for 1 hour to obtain a copolymer solution. When the solution temperature was 30 ° C., a 30% NaOH aqueous solution was added dropwise to adjust the solution pH to 7. The weight average molecular weight of the obtained copolymer was 7500, and Mw / Mn was 1.65. This copolymer is referred to as “copolymer (A3)”.

Production Example 4
A reaction vessel equipped with a thermometer, a stirrer, a reflux device and a dropping device was charged with 219.0 parts by weight of water, heated to 60 ° C., and purged with nitrogen at 200 ml / min for 1 hour. _{Thereafter, H- (OC 2 H 4)} 13 - (OC 3 H 6) 2 - (OC 2 H 4) 351.2 parts by weight of methacrylic acid esters of 10 -OCH _3, 108.8 parts by weight of methacrylic acid, water 119 A mixed solution (1) of 3 parts by weight and 7.6 parts by weight of 2-mercaptopropionic acid in 3 hours is a mixed solution of 3.5 parts by weight of 30% hydrogen peroxide aqueous solution and 71.5 parts by weight of water ( 2) A mixed solution (3) of 1.4 parts by weight of L-ascorbic acid and 73.6 parts by weight of water was continuously added dropwise to a reaction vessel maintained at 60 ° C. for 4 hours. Furthermore, the temperature was maintained at 60 ° C. for 1 hour to obtain a copolymer solution. When the solution temperature was 30 ° C., a 30% NaOH aqueous solution was added dropwise to adjust the solution pH to 7. The weight average molecular weight of the obtained copolymer was 8600, and Mw / Mn was 1.56. This copolymer is referred to as “copolymer (A4)”.

Production Example 5
A reaction vessel equipped with a thermometer, a stirrer, a reflux device and a dropping device was charged with 283.4 parts by weight of water and heated to 100 ° C. Thereafter, a mixed solution of 373.6 parts by weight of methoxypolyethyleneglycol methacrylate (average added mole number 10), 86.4 parts by weight of methacrylic acid, 126.9 parts by weight of water, and 15.3 parts by weight of 2-mercaptopropionic acid ( A mixed solution (2) of 5.6 parts by weight of ammonium persulfate and 69.4 parts by weight of water was continuously added dropwise to the reaction vessel maintained at 100 ° C. for 5 hours. Furthermore, the temperature was maintained at 100 ° C. for 1 hour to obtain a copolymer solution. When the solution temperature was 30 ° C., a 30% NaOH aqueous solution was added dropwise to adjust the solution pH to 7. The weight average molecular weight of the obtained copolymer was 5800, and Mw / Mn was 1.42. This copolymer is referred to as “copolymer (A5)”.

Production Example 6
In a reaction vessel equipped with a thermometer, a stirrer, a reflux device and a dropping device, 293.7 parts by weight of water was charged, the temperature was raised to 70 ° C., and the atmosphere was replaced with nitrogen at 200 ml / min for 1 hour. Thereafter, a mixed solution of 363.5 parts by weight of methoxypolyethyleneglycol methacrylate (average added mole number 10), 96.5 parts by weight of methacrylic acid, 123.5 parts by weight of water, and 6.8 parts by weight of 2-mercaptopropionic acid ( 1) was added dropwise over 4 hours, and a mixed solution (2) of 4.6 parts by weight of ammonium persulfate and 70.4 parts by weight of water was continuously added dropwise to a reaction vessel maintained at 100 ° C. for 5 hours. Furthermore, the temperature was maintained at 70 ° C. for 1 hour to obtain a copolymer solution. When the solution temperature was 30 ° C., a 30% NaOH aqueous solution was added dropwise to adjust the solution pH to 7. The weight average molecular weight of the obtained copolymer was 18000, and Mw / Mn was 2.05. This copolymer is referred to as “copolymer (B1)”.

Production Example 7
In a reaction vessel equipped with a thermometer, a stirrer, a reflux apparatus and a dropping apparatus, 2373 parts by weight of water and an unsaturated polyalkylene glycol monomer as an ethylene oxide adduct (average addition) of 3-methyl-3-buten-1-ol Mole number 50) 4800 parts by weight and 8.7 parts by weight of acrylic acid were charged, heated to 58 ° C., and purged with nitrogen at 200 ml / min for 1 hour. Thereafter, a mixed solution (1) of 21.5 parts by weight of 30% hydrogen peroxide and 460 parts by weight of water was added to the reaction vessel, 640.4 parts by weight of acrylic acid was added dropwise over 3 hours, and L-ascorbic acid 9. A mixed solution (2) of 8 parts by weight, 25.3 parts by weight of 2-mercaptopropionic acid and 1310 parts by weight of water was continuously added dropwise to a reaction vessel maintained at 58 ° C. for 3.5 hours. Furthermore, the temperature was maintained at 58 ° C. for 1 hour to obtain a copolymer solution. When the solution temperature was 30 ° C., a 30% aqueous NaOH solution was added dropwise to adjust the solution pH to 6.5. The weight average molecular weight of the obtained copolymer was 35000, and Mw / Mn was 2.04. This copolymer is referred to as “copolymer (B2)”.

Production Example 8
Epomin (registered trademark) SP-006 (manufactured by Nippon Shokubai Co., Ltd., polyethyleneimine, Mn = 600, acetonitrile content 1 ppm or less) 414.8 g was equipped with an ethylene oxide introduction tube, a nitrogen introduction tube, a stirring blade and a pressure gauge The mixture was charged into a .75 L autoclave, sufficiently purged with nitrogen, and then heated to 145 ° C. After introducing nitrogen to adjust the internal pressure to 0.3 MPa, 392.5 g of ethylene oxide was fed. After maintaining the feed at 145 ° C. for 1 hour after the end of the feed, it was cooled to 80 ° C. The internal pressure is brought to normal pressure, 66.6 g of 48% KOH aqueous solution is added, the temperature is raised to 130 ° C., the pressure is reduced to 0.05 MPa while nitrogen bubbling at a flow rate of 40 ml / min, and sufficient dehydration takes about 5 hours. Went. After completion of the dehydration, the system temperature was set to 155 ° C., nitrogen was introduced to adjust the internal pressure to 0.25 MPa, and then 1060.2 g of ethylene oxide was fed and maintained at 155 ° C. for 1 hour, and the polyethyleneimine polyethylene oxide adduct A Got. However, in the above reaction, the internal pressure was 0.8 MPa or less and the temperature was ± 5 ° C.

The obtained polyethyleneimine polyethylene oxide adduct A (367.5 g) was charged into a 3.75 L autoclave equipped with an ethylene oxide introduction tube, a nitrogen introduction tube, a stirring blade and a pressure gauge, and after sufficient nitrogen substitution, 160 The temperature was raised to ° C. After introducing nitrogen and adjusting the internal pressure to 0.1 MPa, 1350.5 g of ethylene oxide was fed. After keeping the feed at 160 ° C. for 1 hour, it was cooled to 50 ° C. The system was brought to atmospheric pressure, and 9.0 g of 68% acetic acid and 37.5 g of ion-exchanged water were added to obtain a polyethyleneimine polyethylene oxide adduct B. However, in the above reaction, the internal pressure was 0.8 MPa or less and the temperature was ± 5 ° C.
Polyethyleneimine polyethylene oxide adduct B had an OHV (hydroxyl value) of 73.1 and a UV transmittance of 88.0%. The thus obtained polyethyleneimine polyethylene oxide adduct B is referred to as “compound (C1)”.
In actual use, an 80% aqueous solution was used for easy handling.

The OHV (hydroxyl value) and UV transmittance of the polyethyleneimine polyethylene oxide adduct B were determined as follows.
<OHV (hydroxyl value)>
As a blank, put a stir bar in a flask containing no sample, and then add 9 ml of a phthalating reagent (a reagent in which 444 g of phthalic anhydride was dissolved in pyridine to make 3.0 L. The phthalic anhydride concentration was about 1 mol / L). Three points were added using a dispenser (automatic dispenser, manufactured by Hiranuma Sangyo Co., Ltd., UCB-100).
In addition, as a sample, about 0.8 g of the sample was collected in the flask with care not to adhere to the inner wall and weighed carefully. Then, a stirring bar was placed in the flask, and 9 ml of the phthalating reagent was dispensed (automatic dispenser, Hiranuma Sangyo). Three points were prepared by adding them with UCB-100) and stirring.
Each flask was covered and heated on a hot plate (Inai NEO HOTPLATE HI-100 type) adjusted to a surface temperature of 115 ± 5 ° C. (actual measurement value), and reacted for 60 minutes. During the reaction, stirring was performed once every 15 minutes.
After completion of heating, 60 ml of pure water was added to each flask and stirred, followed by titration from a blank with a 0.5 mol / L-KOH solution (manufactured by Wako Pure Chemical Industries, Ltd., for volumetric analysis). In addition, as a dispenser for adding the 0.5 mol / L-KOH solution, an automatic dispenser (manufactured by Kyoto Electronics Co., Ltd., EBU-610-20B type) is used, and an automatic titrator (Kyoto) is used for the titration. An electronic company, AT-610 type) was used.
The hydroxyl value (OHV) was calculated according to the following formula, and the average value of the results was defined as the hydroxyl value (OHV) of the polyethyleneimine polyethylene oxide adduct B.

The notations in the above formula are as follows.
VBl: Blank titration (ml)
VSa: Sample titration (ml)
N: Concentration of KOH solution (mol / L)
F: Factor of 0.5 mol / L KOH solution S: Sample collection amount (g)
56.11: Molecular weight of KOH

<UV transmittance>
The UV transmittance (%) of the polyethyleneimine polyethylene oxide adduct B at a wavelength of 440 nm was evaluated using an absorptiometer (manufactured by Shimadzu Corporation, spectrophotometer UV-1700).

Comparative production example 1
A reaction vessel equipped with a thermometer, a stirrer, a reflux device and a dropping device was charged with 201.8 parts by weight of water, heated to 70 ° C., and purged with nitrogen at 200 ml / min for 1 hour. Thereafter, a mixed solution of 363.5 parts by weight of methoxypolyethylene glycol methacrylate (average addition mole number 6), 96.5 parts by weight of methacrylic acid, 123.5 parts by weight of water, and 6.7 parts by weight of 2-mercaptopropionic acid ( 1) for 4 hours, a mixed solution (2) of 4.8 parts by weight of a 30% aqueous hydrogen peroxide solution and 70.2 parts by weight of water, a mixed solution of 1.9 parts by weight of L-ascorbic acid and 73.1 parts of water ( 3) was continuously added dropwise to a reaction vessel maintained at 70 ° C. for 5 hours. Furthermore, the temperature was maintained at 70 ° C. for 1 hour to obtain a copolymer solution. When the solution temperature was 30 ° C., a 30% NaOH aqueous solution was added dropwise to adjust the solution pH to 7. The weight average molecular weight of the obtained copolymer was 8500, and Mw / Mn was 1.67. This copolymer is referred to as “copolymer (D1)”.

Comparative production example 2
A reaction vessel equipped with a thermometer, a stirrer, a reflux device and a dropping device was charged with 212.6 parts by weight of water, heated to 70 ° C., and purged with nitrogen at 200 ml / min for 1 hour. Thereafter, a mixed solution of 373.6 parts by weight of methoxypolyethyleneglycol methacrylate (average added mole number 10), 86.4 parts by weight of methacrylic acid, 126.9 parts by weight of water, and 7.2 parts by weight of 2-mercaptopropionic acid ( 1) for 4 hours, a mixed solution (2) of 3.8 parts by weight of 30% aqueous hydrogen peroxide and 71.2 parts by weight of water, a mixed solution of 1.5 parts by weight of L-ascorbic acid and 73.5 parts of water ( 3) was continuously added dropwise to a reaction vessel maintained at 70 ° C. for 5 hours. Furthermore, the temperature was maintained at 70 ° C. for 1 hour to obtain a copolymer solution. When the solution temperature was 30 ° C., a 30% NaOH aqueous solution was added dropwise to adjust the solution pH to 7. The weight average molecular weight of the obtained copolymer was 12000, and Mw / Mn was 1.80. This copolymer is referred to as “copolymer (D2)”.

Table 1 shows specific compositions of the copolymers obtained in the production examples and comparative production examples.
However, the composition represents the weight ratio when all the carboxylic acid groups in the charged monomer are converted into sodium salts. For example, in Production Example 2, the feeds were 363.5 parts by weight of methoxypolyethylene glycol methacrylate (n = 10) and 96.5 parts by weight of methacrylic acid (Mw 86.09). In this case, methacrylic acid was converted to a sodium salt. Then, it corresponds to 121.1 parts by weight as sodium methacrylate (Mw 108.17). Therefore, PGM10E / SMAA = 363.5 / 121.1 = 75/25.

The symbols in Table 1 are as follows.
SMAA: sodium methacrylate SAA: sodium acrylate PGM10E: methoxypolyethylene glycol methacrylate (average added mole number 10)
PGM6E: Methoxypolyethylene glycol methacrylate (average added mole number 6)
_{EPE613E: H- (OC 2 H 4} ) 3 - (OC 3 H 6) - (OC 2 H 4) 6 -OCH 3 methacrylic acid ester _{EPE10213E: H- (OC 2 H 4} ) 13 - (OC 3 H 6 _{) 2 - (OC 2 H 4} ) 10 -OCH 3 methacrylic acid ester IPN50: 3- methyl-3-butene-1-ethylene oxide adduct ol (average addition mole number 50)
Polyethyleneimine polyethylene oxide adduct B: Compound (C1) obtained in Production Example 8

Examples 1-6, Comparative Examples 1-5
The copolymers obtained in Production Examples and Comparative Production Examples were mixed in the following composition, and concrete evaluation tests were performed under the following conditions as concrete admixtures. For Example 1 and Comparative Example 2, the kneading time was also measured. The results are shown in Table 2.

<Concrete evaluation test>
1. Concrete mixing water: 172 kg / m ³
Cement (ordinary Portland cement manufactured by Taiheiyo Cement): 573.3 kg / m ³
Coarse aggregate (Ome hard sandstone): 866.0 kg / m ³
Fine aggregate (mixture of Shizuoka Kakegawa land sand and Chiba Kimitsu sand, mixing ratio is Kakegawa: Kimitsu = 50/50): 739.0 kg / m ³
In order to adjust the amount of entrained air in the concrete, micro air MA404 (made by Pozzolith Products), which is an antifoaming agent, and micro air MA202 (made by Pozzolith Products), which is an AE agent, are blended, and the amount of air taken is 3 ±. Adjusted to 1%. In addition, the compounding quantity of the concrete admixture with respect to the cement mass was calculated by the solid content of the admixture, and indicated by “% (mass%)” in the table.

2. Concrete production method In the above composition, 50L forced kneading (bread type) mixer is charged with cement and fine aggregate and kneaded for 10 seconds, then water containing concrete admixture, antifoaming agent and AE agent. And kneaded until the mortar was kneaded, and then the coarse aggregate was added and further kneaded for 90 seconds to prepare concrete.

3. Evaluation Method, Evaluation Criteria (1) Addition Amount Based on the addition amount of concrete admixture shown in Table 2 (addition amount with respect to cement mass, solid content conversion), evaluation was performed as follows.
(Double-circle): The said addition amount is less than 0.3.
○: 0.3 or more and less than 0.35.
Δ: 0.35 or more and less than 0.4.
X: It is 0.4 or more.

(2) Retention property First, the slump flow value (unit: mm) of the obtained concrete was measured in accordance with Japanese Industrial Standards (JIS A 1101, 1128, 6204 (2005)) and immediately after kneading (0 minutes) After) After obtaining the slump flow value after 10 minutes, 35 minutes and 65 minutes, the slump flow value immediately after kneading (0 minutes) is subtracted from the slump flow value after 65 minutes after kneading. The value is shown in Table 2 as “65-0”. Based on the value, “retention” was evaluated as follows.
A: The value is 0 or more.
○: -20 or more and less than 0.
Δ: -40 or more and less than -20.
X: Less than -40.

(3) Concrete condition The condition of concrete was evaluated as follows.
When concrete is rubbed with a scoop, the viscosity of the concrete is high, and a large amount of mortar adheres to the scoop. The condition of the concrete is poor, the lower the viscosity of the concrete, the less mortar adheres to the scoop. The better, the better the concrete. Specifically, it is as follows.
(Double-circle): The viscosity of concrete is low at the time of kneading, and there is almost no adhesion of the mortar part to a scoop.
○: The viscosity of the concrete is low at the time of re-mixing, but adhesion of mortar to the scoop is observed.
(Triangle | delta): The viscosity of concrete is high at the time of mixing, and adhesion of the mortar part to a scoop is also seen.
X: The viscosity of the concrete is high at the time of kneading, and there is much adhesion of mortar to the scoop.

(4) T-stop (second) value T-stop value was measured as one of the indexes representing the viscosity of concrete. The T-stop value is the number of seconds it takes for the concrete to stop flowing from the moment the slump cone is pulled up when measuring the slump / flow value of the concrete. The smaller the T-stop value, the faster the concrete flows and the lower the viscosity of the concrete. However, since the T-stop value is affected by the flow value of concrete and the elapsed time after concrete kneading, the flow value immediately after kneading is adjusted to approximately the same level (within 590 ± 20 mm) in the examples / comparative examples. T-stop (second) values were measured.
Based on the value, evaluation was performed as follows.
A: The value is less than 25 seconds.
○: 25 seconds or more and less than 30 seconds.
Δ: 30 seconds or more and less than 35 seconds.
X: 35 seconds or more.

<Measurement of kneading speed>
Cement and fine aggregate are put into a 50L biaxial forced kneader mixer for 10 seconds and blended with water mixed with concrete admixture, and kneaded with the blending of 1 above, resulting in sufficient smoothness. The time (second) at that time was measured in increments of 10 seconds, and this was taken as the kneading time (second).

From the results in Table 2, the following can be understood.
That is, in Examples 1 to 6 using a concrete admixture containing at least the copolymer (A) and the compound (C) of the present invention, fluidity (water-reducing property), retainability and workability (concrete state and In any of the cases of good viscosity, it is shown that suitable results were obtained, and it can be seen that the effect of simultaneously exhibiting the fluidity, retention and workability of the present invention is excellent. Moreover, from the comparison result of the kneading speed in Example 1 and Comparative Example 2 performed in the same manner as in Example 1 except that the compound (C) was not used, the copolymer (A) of the present invention and the compound (C ) In combination with the effect of simultaneously exhibiting fluidity, retention and workability, the kneading speed with the cement composition can be greatly improved, and productivity can be increased. I understand that.

On the other hand, in Comparative Example 1 in which only one type of copolymer other than the copolymer (A) was used, the required amount of addition was small compared to Examples 1 to 6, but the change in slump flow value with time and evaluation of viscosity The T-stop value that can be obtained is remarkably large, which is inferior to those of Examples 1 to 6 in terms of retention and viscosity. Further, in Comparative Example 3 in which one type of copolymer (A) and another copolymer are used in combination, and the compound (C) is not used, the amount added is larger than those in Examples 1 to 6, and T -Stop value is remarkably large, resulting in poor water reduction and viscosity. Further, in Comparative Example 2 in which only the copolymers (A) and (B) are used and the compound (C) is not used, the necessary addition amount is large, the T-stop value is remarkably large, water reduction and viscosity are reduced. In Comparative Example 6 in which the blending ratio of the copolymer (B) and the copolymer was different from that in Comparative Example 2, the required addition amount was small, but the change in slump flow value with time and T- The stop value is remarkably large, resulting in inferior retention and viscosity. And in the comparative example 4 which uses only a copolymer (B) and a compound (C) and does not use the copolymer (A), a favorable result is obtained about retainability, the state of concrete, and a viscosity. However, it can be seen that the amount added is much larger and the water-reducing property is remarkably inferior.

Claims (8)

A concrete admixture copolymer composition comprising a polycarboxylic acid copolymer and a polyamine polyalkylene oxide adduct,
The polycarboxylic acid-based copolymer has a polyalkylene glycol chain having an average number of repeating alkylene glycol units of 8 or more, and has a weight average molecular weight (Mw) of less than 10,000. Copolymer composition for agent. The polycarboxylic acid copolymer is represented by the following general formula (1);

(In the formula, R ¹ , R ² and R ³ are the same or different and each represents a hydrogen atom, a methyl group or — (CH ₂ ) x COOM ^2. Note that — (CH ₂ ) x COOM ² represents —COOM ¹ or other _- (CH ²⁾ _xCOOM 2 and good .x also form an anhydride is .M ¹ and ^{M 2} is an integer of 0 to 2 are the same or different, a hydrogen atom, a monovalent metal atom Represents a divalent metal atom, a trivalent metal atom, a quaternary ammonium base or an organic amine base.) And an unsaturated carboxylic acid monomer (a1) represented by the following general formula (2);

(.AO ^wherein, R 4, ^{R 5} and ^{R 6} are the same or different, .R ⁷ represents a hydrogen atom or a methyl group, represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms are the same Or, differently, it represents one or more of oxyalkylene groups having 2 to 18 carbon atoms, and when there are two or more oxyalkylene groups represented by AO, these groups are introduced in a block form. And y is an integer of 0 to 2. z is 0 or 1. n1 represents the average number of added moles of the oxyalkylene group; The unsaturated polyalkylene glycol monomer (b1) represented by the unsaturated polyalkylene glycol monomer (b1) represented by the copolymer is obtained by copolymerization. The copolymer set for concrete admixture according to claim 1. Thing. The copolymer composition for a concrete admixture according to claim 1 or 2, comprising two or more of the polycarboxylic acid copolymers. The co-polymer for concrete admixture according to any one of claims 1 to 3, further comprising a polycarboxylic acid copolymer (B) different from the polycarboxylic acid copolymer (A). Combined composition. The polycarboxylic acid copolymer (B) has the following general formula (3);

^(Wherein, R 8, ^{R 9} and ^{R 10} are the same or different, a hydrogen atom, a methyl group or _- represents a (CH 2) pCOOM ⁴ _{Note, -. (CH 2) pCOOM} 4 is -COOM ³ or It may form an anhydride with other — (CH ₂ ) pCOOM ^4. p is an integer of 0 to 2. M ³ and M ⁴ are the same or different and are a hydrogen atom or a monovalent metal atom. Represents a divalent metal atom, a trivalent metal atom, a quaternary ammonium base or an organic amine base.) And an unsaturated carboxylic acid monomer (a2) represented by the following general formula (4);

(.AO ^wherein, R ^{11, R 12} and ^{R 13} are the same or different, ^{.R 14} represents a hydrogen atom or a methyl group, represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms are the same Or, differently, it represents one or more of oxyalkylene groups having 2 to 18 carbon atoms, and when there are two or more oxyalkylene groups represented by AO, these groups are introduced in a block form. May be introduced randomly, q is an integer of 0 to 2. r is 0 or 1. n2 represents the average number of added moles of the oxyalkylene group; The unsaturated polyalkylene glycol monomer (b2) represented by the unsaturated polyalkylene glycol monomer (b2) represented by the copolymer is obtained by copolymerization. The concrete admixture of claim 4 Combined composition. The polycarboxylic acid copolymer (B) has a weight average molecular weight (Mw) of 10,000 or more, and the following formula:
An value = A value × 100 × n
(In the formula, the value A is the total mass of all monomer components when the carboxylic acid groups in the charged monomer are all sodium salts during the production of the polycarboxylic acid copolymer (B). This represents the mass ratio (mass%) of the sodium carboxylate-containing monomer with respect to 100 mass%, where n is the average number of alkylene glycol unit repeats of the polyalkylene glycol chain of the polycarboxylic acid copolymer (B). The An value represented by “An value is rounded to an integer by rounding off after the decimal point.” Is described in claim 4, wherein the An value is 230 or more. Copolymer composition for concrete admixture. A concrete admixture comprising the copolymer composition for a concrete admixture according to any one of claims 1 to 6. A cement composition comprising the concrete admixture according to claim 7.