JP4832873B2 - Concrete composition - Google Patents

Description

  The present invention relates to a concrete composition.

  In addition to workability and strength, the quality control of concrete has become an important issue in recent years, and improvement of durability has become an important issue, and management of unit water volume and water-cement ratio has become important. .

When the unit water amount of concrete increases, drying shrinkage, breathing, sedimentation after driving, and the like increase, and cracks and the like occur in the structure concrete, and there is a tendency that properties that are undesirable in terms of durability increase. For example, the reinforced concrete construction standard specification (JASS 5) stipulates that the unit water amount 185 kg / m ³ is the upper limit value in order to make the drying shrinkage rate 8 × 10 ⁻⁴ or less.

  The unit water volume of plain concrete (concrete without dispersant) varies greatly depending on the aggregate used. In order to reduce the unit water volume, high-quality aggregates with good grain shape are required, but the aggregate situation has deteriorated due to the depletion of high-quality and inexpensive natural aggregates, especially in urban areas. Obtaining good aggregate is becoming difficult. And when using the aggregate with many usage ratios of crushed stone and crushed sand, or the aggregate with unstable particle size, in order to obtain workability like a natural aggregate, unit water quantity tends to increase.

In this way, concrete with a high usage rate of aggregates with poor particle shape such as crushed stone and crushed sand (aggregates with a small track record), and the unit water volume of concrete is as high as 170 to 185 kg / m ³ , so-called “high unit water concrete” It is often used especially in the west of Kinki.

  Conventionally, lignin sulfonic acid and oxycarboxylic acid admixtures have been used as dispersants for high unit water content concrete, especially poorly blended concrete with low cement content, but water separation (breathing) and gravel separation have been used. However, workability and properties of the hardened concrete may be impaired.

Patent Document 1 discloses a surfactant composition containing a polycarboxylic acid polymer to which alkylene oxide is added in order to improve these. Patent Document 2 discloses a technique of using a specific phosphate monoester and phosphate diester additive as an additive for poor blended concrete. In Patent Document 3, a phosphate ester polymer is proposed as a cement dispersant.
JP 2000-351992 A JP 2005-22907 A JP 2000-327386 A

  In high-unit-water concrete, since a large amount of breathing water is likely to be generated, adhesion of the mortar part and coarse aggregate is prevented, and the coarse aggregate is discharged onto the concrete surface, resulting in a rough concrete surface. In addition, such a concrete having a high amount of breathing water reduces the concrete strength itself, the adhesion strength with the reinforcing bars, the workability / fillability, or the water permeability / air permeability of the hardened concrete. It is adversely affected.

  The lignin-based cement dispersant, which is a high unit water content concrete and is widely used as an additive for concrete used at a W / P of 40 to 70%, can impart good fluidity to the fresh state. As described above, there are problems such as insufficient material separation resistance, occurrence of breathing, and unstable entrained air amount in concrete that plays an important role in the frost damage resistance of concrete. By using a polycarboxylic acid-based cement dispersant (for example, Patent Document 1) that has been widely used in recent years, the occurrence of breathing can be suppressed, but it is not yet sufficient, and the stability of the entrained air amount has been sufficiently improved. That's not true.

  Furthermore, the specific phosphoric acid monoester and phosphoric acid diester additive as in Patent Document 2 is very excellent in workability, breathing suppressing power, and stabilization of entrained air amount, but the strength and appearance of the obtained cured product. There is a tendency that a certain amount of antifoaming agent is required to reduce the variation of the product (improvement of product stability).

  An object of the present invention is to provide a concrete composition having good workability such as driving, compacting, finishing, etc., stable entrained air amount in a fresh state, fluidity and fluidity retention, and suppressed breathing. is there.

The present invention relates to a monomer 1 represented by the following general formula (1), a monomer 2 represented by the following general formula (2), and a monomer 3 represented by the following general formula (3). A phosphate ester polymer (A) [hereinafter referred to as component (A)] having a weight average molecular weight of 10,000 to 40,000, and a hydraulic powder. A concrete composition containing (B), aggregate (C), and water (D),
The present invention relates to a concrete composition in which the amount of water per 1 m ³ is 170 to 185 kg / m ³ and the paste volume per 1 m ³ (volume of water and hydraulic powder) is 250 to 320 L / m ³ .

[In the formula, R ¹ and R ² are each a hydrogen atom or a methyl group, R ³ is a hydrogen atom, or — (CH ₂ ) _q (CO) _p O (AO) _r R ⁴ , and AO has 2 to 4 carbon atoms. An oxyalkylene group or an oxystyrene group, p is a number of 0 or 1, q is a number of 0 to 2, r is an average added mole number of AO, a number of 3 to 50, R ⁴ is a hydrogen atom or a carbon number of 1 Represents an alkyl group of ˜18. ]

[Wherein R ¹¹ is a hydrogen atom or a methyl group, R ¹² is an alkylene group having 2 to 12 carbon atoms, m1 is a number of 1 to 30, M ³ and M ⁴ are a hydrogen atom, an alkali metal or an alkaline earth metal, respectively. Represents. ]

[Wherein R ¹³ and R ¹⁵ are each a hydrogen atom or a methyl group, R ¹⁴ and R ¹⁶ are each an alkylene group having 2 to 12 carbon atoms, m2 and m3 are each a number of 1 to 30 and M ⁵ is Represents a hydrogen atom, an alkali metal or an alkaline earth metal. ]

The present invention also relates to a monomer 1 represented by the general formula (1), a monomer 2 represented by the general formula (2), and a single monomer represented by the general formula (3). It is a polymer obtained by copolymerizing the body 3, and is an additive for concrete containing a phosphate ester polymer having a weight average molecular weight of 10,000 to 40,000,
It is composed of hydraulic powder, aggregate and water, and the amount of water per 1 m ³ at the time of mixing is 170 to 185 kg / m ³ and the paste volume per 1 m ³ (volume of water and hydraulic powder) ) Relates to an additive for concrete used in concrete having 250 to 320 L / m ³ .

In the present invention, the concrete additive (A) of the present invention is mixed with the hydraulic powder (B), the aggregate (C), and water (D), and the amount of water per 1 m ³ is 170- 185kg / m ^3, 1m ³ per paste volume (volume of water and hydraulic powder) is 250~320L / m ^3, and slump to produce a concrete composition which is 6～23Cm, the concrete composition It relates to a manufacturing method.

  According to the present invention, there is provided a concrete composition having good workability such as driving, compacting and finishing, stable entrained air amount, fluidity and fluidity retention in a fresh state, and suppressed breathing.

  The present inventors have a concrete composition that has a stable entrained air amount without deteriorating the fluidity and fluidity holding ability and breathing suppressing power in the fresh state, and also has good air bubbles (surface aesthetics) on the hardened concrete surface. As a result of various investigations, it has been found that such a problem can be solved by a concrete composition containing a phosphate ester polymer having a specific structure.

Examples of high unit water concrete to which the present invention is directed, in concrete used in the unit water ^{175kg / m 3 ~185kg / m 3} , in particular, reinforced concrete construction Standard Specification (JASS5), 5 Section Formulation , Commentary Table 5.4 Concrete with the conditions shown in parentheses in the table described in the standard unit water volume of ordinary concrete using ordinary Portland cement and AE water reducing agent is preferred. For example, when crushed stone is used, the slump is 18, 21 cm, etc. at a water cement ratio of 40-50% (crushed stone: maximum dimension 20 mm, unit volume mass 1.54 kg / L, actual rate 59.4%, sand: (In the case of a coarse particle ratio of 2.8, a unit volume mass of 1.70 kg / L, and a performance ratio of 65.4%)

<(A) component>
The component (A) is represented by the monomer 1 represented by the general formula (1), the monomer 2 represented by the general formula (2), and the general formula (3). It is a polymer obtained by copolymerizing the monomer 3, and a phosphate ester polymer having a weight average molecular weight of 10,000 to 40,000.

[Monomer 1]
In monomer 1, R ¹ and R ² in general formula (1) are each a hydrogen atom or a methyl group. R ³ is a hydrogen atom or — (CH ₂ ) _q (CO) _p O (AO) _r R ⁴ , preferably a hydrogen atom. R ⁴ is a hydrogen atom or an alkyl group having 1 to 18 carbon atoms, preferably 1 to 12, more preferably 1 to 4, and further preferably 1 or 2, and particularly preferably a methyl group. When p is 0, AO forms an ether bond with (CH ₂ ) _q, and when p is 1, it forms an ester bond. q is 0 to 2, preferably 0 or 1, and more preferably 0. AO is an oxyalkylene group having 2 to 4 carbon atoms or an oxystyrene group, and AO is preferably an oxyalkylene group having 2 to 4 carbon atoms, more preferably an ethyleneoxy group (hereinafter referred to as EO group), and an EO group. Is 70 mol% or more, more preferably 80 mol% or more, and further preferably 90 mol% or more, and in particular, all AO is preferably an EO group. r is the average number of added moles of AO, and is a number of 3-50, preferably 4-30, more preferably 5-25, still more preferably 6-20, particularly preferably from the viewpoint of suppressing breathing. 6-15. Moreover, AO is different in an average of r repeating units, and random addition, block addition, or a mixture thereof may be included. For example, AO can contain a propyleneoxy group etc. besides EO group.

  Monomer 1 includes a half-terminated alkyl-capped polyalkylene glycol such as methoxypolyethylene glycol, methoxypolypropylene glycol, methoxypolybutylene glycol, methoxypolystyrene glycol, ethoxypolyethylenepolypropyleneglycol, (meth) acrylic acid, maleic acid (half ) Esterified products, etherified products with (meth) allyl alcohol, and (meth) acrylic acid, maleic acid, and (meth) allyl alcohol adducts having 2 to 4 carbon atoms are preferably used. In addition, (meth) acrylic acid means acrylic acid and / or methacrylic acid, and (meth) allyl means allyl and / or methallyl (the same applies hereinafter).

  More preferred is an esterified product of alkoxy, particularly methoxypolyethylene glycol and (meth) acrylic acid. Specific examples include ω-methoxypolyoxyalkylene methacrylate and ω-methoxypolyoxyalkylene acrylate, and ω-methoxypolyoxyalkylene methacrylate is more preferable.

  The monomer 1 used for the production of the component (A) can be obtained, for example, by esterification of an alkoxypolyalkylene glycol and (meth) acrylic acid. From the viewpoint of the required addition amount and viscosity reduction when the esterified product is used in the concrete composition of the present invention, the unreacted (meth) acrylic acid is 5% by weight with respect to the monomer 1 in terms of acid type. The following is preferable, 3% by weight or less is more preferable, 1.5% by weight or less is further preferable, and 1% by weight or less is more preferable. Examples of a method for reducing the amount of (meth) acrylic acid remaining during the production of the monomer 1 include topping, steaming, and solvent extraction.

[Monomer 2]
In the monomer (2), R ¹¹ is a hydrogen atom or a methyl group, and R ¹² is an alkylene group having 2 to 12 carbon atoms. m1 is a number from 1 to 30, and M ³ and M ⁴ are each a hydrogen atom, an alkali metal, or an alkaline earth metal. 1-20 are preferable, as for m1 in General formula (2), 1-10 are more preferable, and 1-5 are especially preferable.

  Specific examples include phosphoric acid monoesters of organic hydroxy compounds. Specific examples include polyalkylene glycol mono (meth) acrylate acid phosphates. For example, phosphoric acid mono-[(2-hydroxyethyl) methacrylic acid] ester, phosphoric acid mono-[(2-hydroxyethyl) acrylic acid ester] and the like can be mentioned. Among these, phosphoric acid mono-[(2-hydroxyethyl) methacrylic acid] ester is preferable from the viewpoint of ease of production and product quality stability. Further, alkali metal salts, alkaline earth metal salts, ammonium salts, alkylammonium salts and the like of these compounds may be used.

[Monomer 3]
In the monomer 3, in the general formula (3), R ¹³ and R ¹⁵ are each a hydrogen atom or a methyl group, and R ¹⁴ and R ¹⁶ are each an alkylene group having 2 to 12 carbon atoms. m2, m3 is a number of each 1 to 30, M ⁵ represents a hydrogen atom, an alkali metal or alkaline earth metal. M2 and m3 in the general formula (3) are each preferably 1 to 20, more preferably 1 to 10, and particularly preferably 1 to 5.

  Specific examples include phosphoric acid diesters of organic hydroxy compounds. Specific examples include polyalkylene glycol di (meth) acrylate acid phosphoric acid diester. Examples include phosphoric acid di-[(2-hydroxyethyl) methacrylic acid] ester, phosphoric acid di-[(2-hydroxyethyl) acrylic acid] ester, and the like. Among these, di-[(2-hydroxyethyl) methacrylic acid] ester phosphate is preferable from the viewpoint of ease of production and quality stability of the product. Further, alkali metal salts, alkaline earth metal salts, ammonium salts, alkylammonium salts and the like of these compounds may be used.

  Monomers 2 and 3 can be used as a mixed monomer including monomer 2 and monomer 3. Further, as the monomer 2 and the monomer 3, a phosphate ester obtained by reacting the organic hydroxy compound represented by the general formula (4) with a phosphorylating agent may be used.

  The mixed monomer including the monomer 2 and the monomer 3 is obtained as a reaction product by reacting, for example, an organic hydroxy compound represented by the general formula (4) and a phosphorylating agent at a predetermined charge ratio. It can also be manufactured.

[Wherein, R ²⁰ represents a hydrogen atom or a methyl group, R ²¹ represents an alkylene group having 2 to 12 carbon atoms, and m4 represents a number of 1 to 30. ]

  1-20 are preferable, as for m4 in General formula (4), 1-10 are more preferable, and 1-5 are especially preferable.

  Examples of the phosphorylating agent include orthophosphoric acid, phosphorus pentoxide (anhydrous phosphoric acid), polyphosphoric acid, phosphorus oxychloride and the like, and orthophosphoric acid and phosphorus pentoxide are preferable. These may be used alone or in combination of two or more. The amount of the phosphorylating agent in the reaction of the organic hydroxy compound and the phosphorylating agent can be appropriately determined according to the target phosphate ester composition.

  Examples of mixed monomers including monomer 2 and monomer 3 include mono-[(2-hydroxyethyl) methacrylic acid] phosphate and di-[(2-hydroxyethyl) methacrylic acid] phosphate. When the mixture is produced, it can be synthesized by a known technique (for example, JP-A-57-180618).

  As the mixed monomer including the monomer 2 and the monomer 3, a commercial product including a monoester and a diester can be used. For example, Phosmer M, Phosmer PE, Phosmer P (Unichemical) , JAMP514, JAMP514P, JMP100 (all Johoku Chemical), light ester P-1M, light acrylate P-1A (all Kyoeisha Chemical), MR200 (Daihachi Chemical), Kayamar (Nippon Kayaku), Ethyleneglycol methacrylate phosphate (Aldrich) Reagent).

  It has been confirmed that the above-mentioned commercial products and reaction products contain compounds other than the monoester (monomer 2) and diester (monomer 3). These other compounds are considered to be a mixture of polymerizable and non-polymerizable compounds, but in the present invention, such a mixture (mixed monomer) can be used as it is.

  The component (A) according to the present invention is a phosphate ester polymer obtained by copolymerizing the monomer 1, the monomer 2, and the monomer 3. It is also preferable to use a mixed monomer containing monomer 2 and monomer 3.

  In the copolymerization of the monomers, the molar ratio between the monomer 1 and the monomers 2 and 3 is as follows: monomer 1 / (monomer 2 + monomer 3) = 5/95 to 95/5, Furthermore, 10/90 to 90/10 are preferable. The molar ratio of monomer 1, monomer 2 and monomer 3 is as follows: monomer 1 / monomer 2 / monomer 3 = 5 to 95/3 to 90/1 to 80, and further 5 -96 / 3-80 / 1-60 (however, the total is 100) is preferable. In addition, about the monomer 2 and the monomer 3, the molar ratio and mol% shall be calculated based on an acid type compound (hereinafter the same).

  Moreover, in manufacture of (A) component, it is preferable that the ratio of the monomer 3 shall be 1-60 mol% and also 1-30 mol% in all the monomers used for reaction.

  The molar ratio of monomer 2 to monomer 3 is preferably monomer 2 / monomer 3 = 99/1 to 4/96, more preferably 99/1 to 5/95.

From the viewpoint of suppressing gelation, the monomer solution containing monomer 2 and / or monomer 3 is preferably used for the reaction at a pH of 7 or less.

Hereinafter, more preferable production conditions will be described from the viewpoints of suppression of gelation, adjustment of a suitable molecular weight, and performance design of the component (A). From such a viewpoint, at the time of copolymerization, 4 mol% or more, further 6 mol% or more, particularly 8 mol% or more of the chain transfer agent is used with respect to the total number of moles of the monomers 1, 2 and 3. It is preferable. The upper limit of the amount of chain transfer agent used is preferably 100 mol% or less, more preferably 60 mol% or less, still more preferably 30 mol% or less, based on the total number of moles of monomers 1, 2 and 3. Most preferably, it can be 15 mol% or less. More specifically, (1) when r of monomer 1 is 3 to 30,
(1-1) When the total molar ratio of the monomers 1, 2 and 3 of the monomer 2 and the monomer 3 is 50 mol% or more, the chain transfer agent is the monomers 1, 2 and 3 It is preferable to use 6 to 100 mol%, particularly 8 to 60 mol%, based on the total of
(1-2) When the molar ratio in the sum of monomers 1, 2 and 3 of monomer 2 and monomer 3 is less than 50 mol%, the chain transfer agent is monomer 1, 2 and It is preferable to use 4 to 60 mol%, particularly 5 to 30 mol%, based on the total of 3.
(2) When r of monomer 1 used for component (A) is more than 30, the chain transfer agent is used in an amount of 6 to 50 mol%, particularly 8 to 40 mol%, based on monomers 1 to 3. Is preferred.

  The reaction rate of the monomers 2 and 3 is preferably 60% or more, more preferably 70% or more, more preferably 80% or more, more preferably 90% or more, and particularly preferably 95% or more. It can be selected from the viewpoint. Here, the reaction rate of the monomers 2 and 3 is calculated by the following equation.

In addition, the ratio (mol%) of the ethylenically unsaturated bond of the monomer 2 and the monomer 3 in the phosphorus-containing compound in the reaction system at the start and end of the reaction is measured by the following ¹ H-NMR. It can be calculated based on the result.
[ ¹ H-NMR conditions]
The component (A) dissolved in water and dried under reduced pressure is dissolved in deuterated methanol at a concentration of 3 to 4% by weight, and ¹ H-NMR is measured. The residual ratio of ethylenically unsaturated bonds is measured by an integral value of 5.5 to 6.2 ppm. In addition, the measurement of ¹ H-NMR uses “Mercury 400 NMR” manufactured by Varian, the number of data points is 42052, the measurement range is 6410.3 Hz, the pulse width is 4.5 μs, the pulse waiting time is 10 S, and the measurement temperature is 25.0 ° C. Perform under conditions.

  In the production of the component (A), in addition to the monomers 1, 2, and 3, other monomers that can be copolymerized can be used. Examples of other copolymerizable monomers include allyl sulfonic acid, methallyl sulfonic acid, any of these alkali metal salts, alkaline earth metal salts, ammonium salts, and amine salts. In addition, acrylic monomers such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, and the like, and any one or more of alkali metal salts, alkalis Anhydrous compounds such as earth metal salts, ammonium salts, amine salts, methyl esters, ethyl esters and maleic anhydride may also be used. Furthermore, (meth) acrylamide, N-methyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, 2- (meth) acrylamide-2-metasulfonic acid, 2- (meth) acrylamide-2-ethanesulfonic acid, Examples include 2- (meth) acrylamide-2-propanesulfonic acid, styrene, styrenesulfonic acid and the like. The total proportion of monomers 1, 2, and 3 in all monomers is preferably 30 to 100 mol%, more preferably 50 to 100 mol%, particularly preferably 75 to 100 mol%, and more than 95 mol% to 100 Mole%, more preferably 97-100 mol% is preferred.

  In the production of component (A), the monomer is preferably copolymerized in the presence of a predetermined amount of chain transfer agent. Moreover, you may use the other monomer, polymerization initiator, etc. which can be copolymerized.

  The reaction temperature of the monomers 1, 2 and 3 is preferably 40 to 100 ° C., more preferably 60 to 90 ° C., and the reaction pressure is 101.3 to 111.5 kPa (1 to 1.1 atm) in gauge pressure. 3-106.4 kPa (1-1.05 atm) is preferred.

  The pH of the reaction system can be adjusted with an inorganic acid (phosphoric acid, hydrochloric acid, nitric acid, sulfuric acid, etc.), NaOH, KOH, triethanolamine, or the like, if necessary.

  Here, the monomer solution containing the monomer 2 and / or the monomer 3 is preferably a water-containing system (that is, the solvent contains water) for pH measurement. May be measured by adding the required amount of water. From the viewpoint of uniformity of the monomer solution, prevention of gelation, and suppression of performance degradation, the pH is preferably 7 or less, more preferably 0.1 to 6, and further preferably 0.2 to 4.5. Monomer 1 is also preferably used as a monomer solution having a pH of 7 or less. This pH is at 20 ° C.

  In the present invention, the pH at 20 ° C. of the reaction solution collected during the reaction (from the start of the reaction to the end of the reaction) is defined as the pH during the reaction. It is preferable to start the reaction under conditions that clearly show that the pH during the reaction is 7 or less (monomer ratio, solvent, other components, etc.).

  When the reaction system is non-aqueous, it can be measured by adding an amount of water capable of measuring pH to the reaction system.

In the method for producing the component (A), the monomers 1, 2 and 3 are reacted under the conditions exemplified in the following (1) and (2), usually under consideration of other conditions, The pH during the reaction is considered to be 7 or less.
(1) A monomer solution having a pH of 7 or less containing all of the monomers 1, 2 and 3 is used for the copolymerization reaction of the monomers 1, 2 and 3.
(2) The copolymerization reaction of the monomers 1, 2 and 3 is started at pH 7 or less. That is, the reaction is started after the reaction system containing the monomers 1, 2 and 3 is brought to pH 7 or lower.

[Chain transfer agent]
The chain transfer agent has a function of causing a chain transfer reaction in radical polymerization (a reaction in which a growing polymer radical reacts with another molecule to move a radical active site). It is a substance to be added.

  Examples of chain transfer agents include thiol chain transfer agents and halogenated hydrocarbon chain transfer agents, and thiol chain transfer agents are preferred.

As the thiol chain transfer agent, those having a —SH group are preferable, and in particular, the general formula HS—R—Eg (wherein R represents a hydrocarbon-derived group having 1 to 4 carbon atoms, and E is − OH, —COOM, —COOR ′ or —SO ₃ M group, M represents a hydrogen atom, monovalent metal, divalent metal, ammonium group or organic amine group, and R ′ represents an alkyl having 1 to 10 carbon atoms. In which g represents an integer of 1 to 2, for example, mercaptoethanol, thioglycerol, thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thiomalic acid, Examples include octyl thioglycolate, octyl 3-mercaptopropionate, and the like from the viewpoint of chain transfer effect in a copolymerization reaction including monomers 1 to 3. Mercaptoethanol are preferable, more preferably mercaptopropionic acid. These 1 type (s) or 2 or more types can be used.

  Examples of the halogenated hydrocarbon chain transfer agent include carbon tetrachloride and carbon tetrabromide.

  Examples of other chain transfer agents include α-methylstyrene dimer, terpinolene, α-terpinene, γ-terpinene, dipentene, 2-aminopropan-1-ol and the like. A chain transfer agent can use 1 type (s) or 2 or more types.

[Polymerization initiator]
(A) In the manufacturing method of a component, it is preferable to use a polymerization initiator, and it is 5 mol% or more, especially 7-50 mol with respect to the total number of moles of the monomers 1, 2, and 3 especially. %, Particularly 10 to 30 mol% is preferred.

  Examples of aqueous polymerization initiators include ammonium persulfate salt or alkali metal salt, hydrogen peroxide, 2,2′-azobis (2-amidinopropane) dihydrochloride, 2,2′-azobis (2-methylpropionamide) dihydrate, etc. These water-soluble azo compounds can be used. In addition, an accelerator such as sodium bisulfite and an amine compound can be used in combination with the polymerization initiator.

[solvent]
In the production of the component (A), it can be carried out by a solution polymerization method, and the solvent used in that case contains water or water and methyl alcohol, ethyl alcohol, isopropyl alcohol acetone, methyl ethyl ketone or the like. And hydrous solvent solvents. In view of handling and reaction equipment, water is preferred. In particular, when an aqueous solvent is used, the pH of the monomer solution containing the monomer 2 and / or the monomer 3 is preferably 7 or less, more preferably 0.1 to 6, particularly 0.2 to 4. A copolymerization reaction is preferably used for the reaction in terms of uniformity of the monomer mixture (handleability), monomer reaction rate, and suppression of crosslinking by hydrolysis of the pyro compound of the phosphoric acid compound.

  (A) An example of the manufacturing method of a component is shown. A predetermined amount of water is charged into a reaction vessel, the atmosphere is replaced with an inert gas such as nitrogen, and the temperature is raised. Prepare monomer 1, monomer 2, monomer 3, chain transfer agent mixed and dissolved in water, and polymerization initiator dissolved in water, and take 0.5 to 5 hours. Drip into the reaction vessel. At that time, each monomer, chain transfer agent and polymerization initiator may be dropped separately, or a mixed solution of monomers can be charged in a reaction vessel in advance and only the polymerization initiator can be dropped. is there. That is, the chain transfer agent, the polymerization initiator, and other additives may be added as an additive solution separately from the monomer solution, or may be added to the monomer solution after being added. From the viewpoint of stability, it is preferable to supply the reaction system as an additive solution separately from the monomer solution. In any case, the pH of the solution containing the monomer 2 and / or the monomer 3 is preferably 7 or less. Further, the copolymerization reaction is preferably performed with an acid agent or the like while maintaining the pH at 7 or less, and preferably aging is performed for a predetermined time. The polymerization initiator may be added dropwise at the same time as the monomer, or may be added in portions, but it is preferable to add in portions in terms of reducing unreacted monomers. For example, in the total amount of the polymerization initiator to be finally used, 1/2 to 2/3 polymerization initiator is added simultaneously with the monomer, and the remainder is aged for 1 to 2 hours after the completion of the monomer dropping, It is preferable to add. If necessary, it is further neutralized with an alkali agent (such as sodium hydroxide) after completion of ripening to obtain the phosphate ester polymer according to the present invention. This production example is suitable as a method for producing the component (A) according to the present invention.

  The total amount of monomers 1, 2 and 3 in the reaction system and other copolymerizable monomers is preferably 5 to 80% by weight, more preferably 10 to 65% by weight, and particularly preferably 20 to 50% by weight. .

  The component (A) has a weight average molecular weight (Mw) of 10,000 to 40,000. This component (A) has an Mw of 10,000 or more, preferably 12,000 or more, more preferably 13,000 or more, more preferably from the viewpoint of suppressing unreacted monomers (reducing the reaction rate). 14,000 or more, particularly preferably 15,000 or more, and 40,000 or less, preferably 38,000 or less, more preferably 36,000 or less, more preferably 34,000 or less, from the viewpoint of suppressing breathing. Particularly preferably, it is 32,000 or less, and from the viewpoints of both, preferably 12,000 to 38,000, more preferably 13,000 to 36,000, still more preferably 14,000 to 34,000, particularly preferably. Is 15,000-32,000. It is preferable to have Mw in this range and Mw / Mn is 1.0 to 2.6. Here, Mn is a number average molecular weight.

(A) Mw and Mn of a component are measured by the gel permeation chromatography (GPC) method of the following conditions.
[GPC conditions]
Column: G4000PWXL + G2500PWXL (Tosoh)
Eluent: 0.2M phosphate buffer / CH ₃ CN = 9/1
Flow rate: 1.0mL / min
Column temperature: 40 ° C
Detection: RI
Sample size: 0.2mg / mL
Reference material: Polyethylene glycol equivalent

  Further, in the chart pattern showing the molecular weight distribution obtained by the GPC method under the above conditions, the area where the molecular weight is 100,000 or more is 5% or less of the total area of the chart, and the fluidity (required addition amount reduction) More preferable in terms.

<Hydraulic powder (B)>
Cement is an example of the hydraulic powder (B). Examples of the cement include ordinary Portland cement, early-strength Portland cement, ultra-early-strength Portland cement, and eco-cement (for example, JIS R5214). As hydraulic powder other than cement, blast furnace slag, fly ash, silica fume and the like may be included, and non-hydraulic limestone fine powder and the like may be included. Silica fume cement or blast furnace cement mixed with cement may be used.

<Aggregate (C)>
Aggregates (C) include fine aggregates and coarse aggregates. Fine aggregates are preferably mountain sand, land sand, river sand and crushed sand, and coarse aggregates are mountain gravel, land gravel, river gravel and crushed stone. preferable. Depending on the application, lightweight aggregates may be used. The term “aggregate” is based on “Concrete Overview” (published on June 10, 1998, published by Technical Shoin).

<Concrete composition>
The present invention relates to a concrete composition containing the component (A) of the present invention, a hydraulic powder (B), an aggregate (C), and water (D). In the concrete composition of the present invention, the amount of water per 1 m ^{3 of the} composition is 170 to 185 kg / m ³ , preferably 175 to 185 kg / m ³ . The concrete composition of the present invention can be applied as high unit water content concrete.

In the concrete composition of the present invention, the paste volume (volume of water and hydraulic powder) per 1 m ^{3 of the} composition is 250 to 320 L / m ³ , preferably 255 to 315 L / m ³ , more preferably. Is 260 to 310 L / m ³ .

Furthermore, the concrete composition of the present invention, the weight of the hydraulic powder per the composition 1 m ³ (B) is 190~420kg / m ^3, more preferably 200~410kg / m ^3, in particular Preferably it is 210-400 kg / m < ³ >.

  In the concrete composition of the present invention, W / P is preferably 40 to 70%, more preferably 42 to 65%, and particularly preferably 45 to 65%.

  In the concrete composition concrete of the present invention, the component (A) is 0.05 to 0.80 parts by weight, more preferably 0.07 to 0.70 parts by weight, and particularly preferably 0. It is preferable to contain 10-0.50 weight part.

The amount of aggregate (C) is calculated by subtracting the total volume of phosphate ester polymer (A), hydraulic powder (B), water (D), and air volume from 1 m ^{3 of} concrete volume. Amount.

  In producing the concrete composition of the present invention, the component (A) is preferably used as a solution from the viewpoint of workability. Water or an organic solvent can be used as the solvent, and it is preferable from the viewpoint of safety to use an aqueous solution containing water as a solvent, and an aqueous solution in which the concentration (effective component concentration) of the component (A) is 20% by weight or more, It is preferable to exhibit a uniform appearance at 20 ° C. Further, the viscosity at 20 ° C. of the aqueous solution is preferably 500 mPa · s or less, more preferably 300 mPa · s or less, further 1 to 300 mPa · s, further 150 mPa · s or less, and further 1 to 150 mPa · s, It is preferable in terms of workability.

  Moreover, in manufacture of the concrete composition of this invention, a well-known additive (material) other than (A) component can be used. For example, AE agent, fluidizing agent, retarder, early strengthening agent, accelerator, foaming agent, water retention agent, thickener, waterproofing agent, antifoaming agent, shrinkage reducing agent, water-soluble polymer, interface Examples of the activator include silica powder, blast furnace slag, fly ash, and silica fume.

  Among these, it is preferable to use an antifoaming agent. Antifoaming agents include (1) lower alcohols such as methanol and ethanol, (2) silicones such as dimethyl silicone oil and fluorosilicone oil, and (3) mineral oils such as blends of mineral oil and surfactant. (4) Trialkyl phosphate esters such as tributyl phosphate, (5) Fatty acids or fatty acid esters such as oleic acid, sorbitan oleic acid monoester, polyethylene glycol fatty acid ester, polyethylene glycol / polypropylene glycol fatty acid ester, (6 ) Polyoxyalkylenes such as polypropylene glycol and polyethylene glycol / polypropylene glycol alkyl ether. Preferably, it is at least one antifoaming agent selected from fatty acid or fatty acid ester antifoaming agent, silicone antifoaming agent, polyoxyalkylene antifoaming agent and trialkyl phosphate ester antifoaming agent. From the viewpoint of mixing stability with the component (A), more preferably one or more antifoaming agents selected from fatty acid or fatty acid ester antifoaming agents, silicone antifoaming agents, and polyoxyalkylene antifoaming agents. Yes, more preferably one or more antifoaming agents selected from fatty acid or fatty acid ester antifoaming agents and silicone antifoaming agents, particularly preferably fatty acid or fatty acid ester antifoaming agents. The amount of the defoamer added varies depending on the range of the amount of air required by the concrete. Part by weight is preferred, 0.05 to 5 parts by weight is more preferred, and 0.1 to 3 parts by weight is particularly preferred.

<Additives for concrete>
Component (A) of the present invention, a hydraulic powder, it was blended with aggregate, and water, water of 1 m ³ per in formulation is 170~185kg / m ^3, 1m ³ per paste volume ( It can be used as an additive for concrete used in concrete having a volume of water and hydraulic powder (250 to 320 L / m ³ ). The additive for concrete of this invention can contain the said well-known additive (material) other than (A) component.

[Production Example a-1]
A glass reaction vessel (four-necked flask) equipped with a stirrer was charged with 252 g of water, purged with nitrogen while stirring, and heated to 80 ° C. in a nitrogen atmosphere. ω-methoxypolyethylene glycol monomethacrylate [addition mole number of ethylene oxide (hereinafter referred to as EO) 23: NK ester M230G manufactured by Shin-Nakamura Chemical Co., Ltd.], mono (2-hydroxyethyl) methacrylic acid phosphate and diphosphoric acid phosphate A mixture of 18.9 g of a mixture of [(2-hydroxyethyl) methacrylic acid] ester (Fosmer M: Unichemical Co., Ltd.) and 2.1 g of 3-mercaptopropionic acid in 75 g of water and ammonium persulfate. Two of 3.1 g dissolved in 35 g of water were added dropwise over 1.5 hours. After aging for 1 hour, 1.5 g of ammonium persulfate dissolved in 18 g of water was added dropwise over 30 minutes, and then aging was carried out at the same temperature (80 ° C.) for 1.5 hours. After completion of aging, the mixture was neutralized with 23.4 g of a 20% aqueous sodium hydroxide solution to obtain a polymer having a weight average molecular weight of 28,000. (Monomer polymerization pH: 1.3, reaction rate 99%)

[Production Example a-2]
A glass reaction vessel (four-necked flask) equipped with a stirrer was charged with 471 g of water, purged with nitrogen while stirring, and heated to 80 ° C. in a nitrogen atmosphere. 290 g of ω-methoxypolyethyleneglycol monomethacrylate (average added mole number of EO 9) (effective content 84.4%, moisture 10%), phosphoric acid mono [(2-hydroxyethyl) methacrylic acid] ester and phosphoric acid di- [ (2-Hydroxyethyl) methacrylic acid] A mixture of 93.8 g of phosphoric acid ester (A) and 11.3 g of 3-mercaptopropionic acid and ammonium persulfate. Two of the 8.2 g dissolved in 46 g of water were added dropwise over 1.5 hours. After aging for 1 hour, a solution prepared by dissolving 3.3 g of ammonium persulfate in 19 g of water was dropped over 30 minutes, and then aging was performed at the same temperature (80 ° C.) for 1.5 hours. After completion of aging, the copolymer was neutralized with 58.2 g of a 32% aqueous sodium hydroxide solution to obtain a copolymer having a weight average molecular weight of 25,000. (Monomer polymerization pH: 1.0, reaction rate 99%)

The phosphoric acid ester (A) used in this production example was prepared by charging 200 g of 2-hydroxyethyl methacrylate and 36.0 g of 85% phosphoric acid (H ₃ PO ₄ ) in a reaction vessel. Obtained by gradually adding 89.1 g of (phosphoric acid) (P ₂ O ₅ ) while cooling so that the temperature does not exceed 60 ° C., setting the reaction temperature to 80 ° C., reacting for 6 hours, and cooling. Is. This phosphate esterified product (A) was also used in some of the following production examples.

[Production Example a-3]
489 g of water was charged into a glass reaction vessel (four-necked flask) equipped with a stirrer, purged with nitrogen while stirring, and heated to 80 ° C. in a nitrogen atmosphere. 290 g of ω-methoxypolyethyleneglycol monomethacrylate (average added mole number of EO 9) (effective content 84.4%, moisture 10%), phosphoric acid mono [(2-hydroxyethyl) methacrylic acid] ester and phosphoric acid di- [ (2-hydroxyethyl) methacrylic acid] ester mixture (A) 53.2 g and 3-mercaptopropionic acid 9.1 g mixed with ammonium persulfate. Two of 7.8 g dissolved in 44 g of water were added dropwise over 1.5 hours. After aging for 1 hour, a solution prepared by dissolving 3.1 g of ammonium persulfate in 18 g of water was dropped over 30 minutes, and then aging was performed at the same temperature (80 ° C.) for 1.5 hours. After completion of aging, the mixture was neutralized with 33.0 g of a 32% aqueous sodium hydroxide solution to obtain a copolymer having a weight average molecular weight of 24,000. (Monomer polymerization pH: 1.1, reaction rate 98%)

[Production Example b-1]
A glass reaction vessel (four-necked flask) equipped with a stirrer was charged with 247 g of water, purged with nitrogen while stirring, and heated to 80 ° C. in a nitrogen atmosphere. 75 g of ω-methoxypolyethyleneglycol monomethacrylate (EO addition mole number 23: NK ester M230G manufactured by Shin-Nakamura Chemical), mono-[(2-hydroxyethyl) methacrylic acid] phosphate and di-[(2-hydroxyphosphate) Ethyl) methacrylic acid] ester mixture (Fosmer M: Unichemical Co., Ltd.) 18.9 g and 3-mercaptopropionic acid 0.9 g in water 75 g and ammonium persulfate. Two of 3.1 g dissolved in 35 g of water were added dropwise over 1.5 hours. After aging for 1 hour, 1.5 g of ammonium persulfate dissolved in 18 g of water was added dropwise over 30 minutes, and then aging was carried out at the same temperature (80 ° C.) for 1.5 hours. After completion of aging, the mixture was neutralized with 23.4 g of a 20% aqueous sodium hydroxide solution to obtain a polymer having a weight average molecular weight of 48,000. (Monomer polymerization pH: 1.4, reaction rate 100%)

[Production Example b-2]
371 g of water was charged into a glass reaction vessel with a stirrer (four-necked flask), purged with nitrogen while stirring, and heated to 80 ° C. in a nitrogen atmosphere. 500 g of ω-methoxypolyethyleneglycol monomethacrylate (average number of moles of EO added 23) (effective content 60.8%, moisture 35%), mono-[(2-hydroxyethyl) methacrylic acid] phosphate and di-phosphate A mixture of 34.1 g of phosphoric acid ester (A) which is a mixture of [(2-hydroxyethyl) methacrylic acid] ester and 2.8 g of 3-mercaptopropionic acid and ammonium persulfate. Two of 7.2 g dissolved in 41 g of water were added dropwise over 1.5 hours. After aging for 1 hour, 1.6 g of ammonium persulfate dissolved in 9 g of water was added dropwise over 30 minutes, and then aging was carried out at the same temperature (80 ° C.) for 1.5 hours. After completion of aging, the solution was neutralized with 21.2 g of a 32% aqueous sodium hydroxide solution to obtain a copolymer having a weight average molecular weight of 44,000. (Monomer polymerization pH: 1.4, reaction rate 100%)

[Production Example b-3]
A glass reaction vessel (four-necked flask) equipped with a stirrer was charged with 271 g of water, purged with nitrogen while stirring, and heated to 80 ° C. in a nitrogen atmosphere. 83.5 g of ω-methoxypolyethyleneglycol monomethacrylate (EO addition mole number 120), phosphoric acid mono-[(2-hydroxyethyl) methacrylic acid] ester and phosphoric acid di-[(2-hydroxyethyl) methacrylic acid] ester A mixture of 10.1 g of Phosmer M (Unichemical Co., Ltd.) and 1.4 g of 3-mercaptopropionic acid in 83 g of water and ammonium persulfate. Two of 1.2 g dissolved in 13 g of water were added dropwise over 1.5 hours. After aging for 1 hour, 0.6 g of ammonium persulfate dissolved in 7 g of water was added dropwise over 30 minutes, and then aging was carried out at the same temperature (80 ° C.) for 1.5 hours. After completion of aging, the polymer was neutralized with 12.5 g of a 20% aqueous sodium hydroxide solution to obtain a polymer having a weight average molecular weight of 36,000. (Monomer polymerization pH: 1.5, reaction rate 98%)

[Production Example c-1]
A glass reaction vessel with a stirrer (four-necked flask) was charged with 246.4 g of water, purged with nitrogen while stirring, and heated to 56 ° C. in a nitrogen atmosphere. A mixture of 148.8 g of ω-methoxypolyethyleneglycol methacrylate (EO addition number 10), 39.2 g of methacrylic acid and 2.32 g of 3-mercaptopropionic acid, and 43.3 g of 5% aqueous solution of ammonium persulfate, took 1.5 hours each. It was dripped. Thereafter, aging was performed at the same temperature (56 ° C.) for 3 hours. After completion of aging, the mixture was neutralized with 48% sodium hydroxide to pH = 6 to obtain a copolymer. (Weight average molecular weight 50000)

[Production Example c-2]
A glass reaction vessel with a stirrer (four-necked flask) was charged with 281.4 g of water, purged with nitrogen while stirring, and heated to 80 ° C. in a nitrogen atmosphere. ω-methoxypolyethyleneglycol methacrylate (EO added mole number 120) 336.5g, methacrylic acid 22.2g and 2-mercaptoethanol 1.89g dissolved in water 238.2g and ammonium persulfate 3.68g dissolved in water 45g Were added dropwise over 1.5 hours. Subsequently, 1.47 g of ammonium persulfate dissolved in 15 g of water was added dropwise over 30 minutes, and then aging was performed at the same temperature (80 ° C.) for 1 hour. After completion of the aging, the copolymer was neutralized with 18.7 g of 48% sodium hydroxide to obtain a copolymer. (Weight average molecular weight 79000)

[Production Example c-3]
A glass reaction vessel with a stirrer (four-necked flask) was charged with 1053.1 g of water, purged with nitrogen while stirring, and heated to 78 ° C. in a nitrogen atmosphere. 884.5 g of ω-methoxypolyethyleneglycol methacrylate (EO added mole number 120), 28.1 g of methacrylic acid, 98.5 g of methyl acrylate and 5.11 g of 2-mercaptoethanol dissolved in 526.5 g of water and 11.18 g of ammonium persulfate in 63.4 water The two dissolved in g were added dropwise over 1.5 hours. Subsequently, a solution obtained by dissolving 3.73 g of ammonium persulfate in 21.1 g of water was dropped over 30 minutes, and then aging was performed at the same temperature (78 ° C.) for 1 hour. After completion of aging, the mixture was neutralized with 69.4 g of 20% sodium hydroxide to obtain a copolymer. (Weight average molecular weight 81000)

[Production Example d-1]
A glass reaction vessel with a stirrer (four-necked flask) was charged with 500 g of an oleyl alcohol EO adduct (average EO addition mole number 20, hydroxyl value 49.9) and purged with nitrogen to obtain a nitrogen atmosphere. It heated to about 80 degreeC and the water | moisture content was removed under pressure reduction. After normal pressure and about 60 ° C., 9.4 g of phosphoric acid (purity 85%) is added dropwise. After being completely uniform, 26.2 g of commercially available phosphoric anhydride (purity 98%) was added. The addition of phosphoric anhydride was carried out in three portions. After the addition, the liquid temperature was adjusted to 65 to 75 ° C., and aging was performed for about 6 hours. After aging, 26.8 g of tap water was added, the liquid temperature was adjusted to about 80 ° C., and the mixture was further reacted for about 4 hours.

  Measure the acid value 1 of the reaction product, tap water and 48% hydroxylation so that the neutralization degree with respect to the acid value 1 is 0.5 to 1.0 and the concentration is 20% by weight. The mixture was adjusted with an aqueous sodium solution to obtain a phosphoric ester.

[Production Example d-2]
A glass reaction vessel with a stirrer (four-necked flask) was charged with 500 g of myristyl alcohol EO adduct (average EO addition mole number 12, hydroxyl value 74.9), and the atmosphere was replaced with nitrogen while stirring to obtain a nitrogen atmosphere. It heated to about 80 degreeC and the water | moisture content was removed under pressure reduction. After normal pressure and about 60 ° C., 14.1 g of phosphoric acid (purity 85%) is added dropwise. After being completely uniform, 39.3 g of commercially available phosphoric anhydride (purity 98%) was added. The addition of phosphoric anhydride was carried out in three portions. After the addition, the liquid temperature was adjusted to 65 to 75 ° C., and aging was performed for about 6 hours. After aging, 27.7 g of tap water was added, the liquid temperature was adjusted to about 80 ° C., and the mixture was further reacted for about 4 hours.

  Measure the acid value 1 of the reaction product, tap water and 48% hydroxylation so that the neutralization degree with respect to the acid value 1 is 0.5 to 1.0 and the concentration is 20% by weight. The mixture was adjusted with an aqueous sodium solution to obtain a phosphoric ester.

Example 1
High unit water quantity concrete was prepared using the polymers of Tables 2 to 4 and the components of Tables 5 to 7 as shown in Tables 8 to 10 with respect to the concrete blends of Table 1, and the following evaluations were performed. The results are shown in Tables 8-10.

(1) Concrete test (1-1) Concrete mix (mixing)
W: Tap water C: Ordinary Portland cement (Pacific Cement Co., Ltd.), density = 3.16 g / cm ³
S1: Sea sand from Setouchi, surface dry density = 2.54 g / cm ³
S2: Ibaraki crushed stone, surface dry density = 2.64 g / cm ³
G: Ibaraki crushed stone, surface dry density = 2.64 g / cm ³
The above materials were used in the preparation of the concrete blends I-III in Table 1. The amount of air in each of the concrete blends I to III was designed to be 45 L / m ³ .

(1-2) Manufacture of concrete The component of Tables 2-7 was added to the tap water (mixed water) in the concrete mixing of Table 1. At this time, as necessary, as an antifoaming agent, fatty acid ester antifoaming agent Foam Rex 797 (manufactured by Nikka Chemical Co., Ltd.) and silicone antifoaming agent antifoam 013B (manufactured by Dow Corning Asia Ltd .; polyorganosiloxane type) Was added.

  Next, gravel, about half the amount of sand, cement, and the remaining sand were put into a biaxial forced mixer (IHI) in this order. After empty kneading for 10 seconds, the above kneaded water was quickly stirred and added uniformly, and kneaded for 90 seconds. The slump flow was measured for the obtained concrete. At that time, the additive amount was adjusted so that the concrete blend I was slump 15 cm ± 1.5 cm, the concrete blend II was slump 21 cm ± 1.5 cm, and the concrete blend III was slump 21 cm ± 1.5 cm.

(2) Stability of concrete fluidity over time (slump)
In the above (1), the manufactured concrete is stored in a square container (commonly known as a kneaded plate), and the concrete slump (based on JIS A 1101) is measured 30 minutes and 60 minutes after the concrete is mixed. did. However, the kneading was performed using a scoop before measurement.

(3) Measurement of air quantity The air quantity measurement method was measured with the test method (JIS-A1118 method) by the volume of the air quantity of fresh concrete. At that time, the amount of air immediately after kneading (initial air amount) is 4.5 ± 1.5% by volume for all three types of concrete blending, and the air bubble entrainer Mighty AE-03 (manufactured by Kao Corporation) and defoaming It adjusted with the agent (Antifoam E-20: Kao Co., Ltd. product). Air stability was measured from 30 minutes to 60 minutes immediately after kneading. The smaller the difference with respect to the initial air amount, the better the air stability.

(4) Breathing rate The breathing rate was measured according to JIS-A1123 method.

(5) Cured surface bubbles (surface aesthetics)
The prepared concrete is put into a steel mold having a length of 10 cm, a width of 20 cm, and a height of 20 cm, and is vibrated for 20 seconds with a table type vibrator (amplitude 0.15 mm, 3300 vpm). Then, after leaving still in a constant temperature room at 20 ° C. for 48 hours, the mold was removed, and the state of the voids and bubbles of the specimen surface 10 cm × 20 cm × 20 cm = 4000 cm ² was visually observed, and the average of the four surfaces was as follows: evaluated.
○: No bubbles of 3 mm or more Δ: Number of bubbles of 3 mm or more, 1 to 5 ×: Number of bubbles of 3 mm or more, 6 or more

The symbols in the table are as follows (the same applies hereinafter).
MEPEG-E: ω-methoxypolyethylene glycol monomethacrylate, the number in parentheses is the EO average added mole number.
-HEMA-MPE: phosphoric acid mono-[(2-hydroxyethyl) methacrylic acid] ester-HEMA-DPE: phosphoric acid di-[(2-hydroxyethyl) methacrylic acid] ester

* Numbers in parentheses are molar ratios.

  The addition amount in Tables 8 to 10 is a part by weight based on 100 parts by weight of the cement of the total amount of the polymer and other components.

Claims (5)

Monomer 1 represented by the following general formula (1), monomer 2 represented by the following general formula (2), and monomer 3 represented by the following general formula (3) are copolymerized A phosphate ester polymer (A) having a weight average molecular weight of 10,000 to 40,000, a hydraulic powder (B), an aggregate (C), and water. A concrete composition containing (D),
A concrete composition in which the amount of water per 1 m ³ is 170 to 185 kg / m ³ and the paste volume per 1 m ³ (volume of water and hydraulic powder) is 250 to 320 L / m ³ .

[In the formula, R ¹ and R ² are each a hydrogen atom or a methyl group, R ³ is a hydrogen atom, or — (CH ₂ ) _q (CO) _p O (AO) _r R ⁴ , and AO has 2 to 4 carbon atoms. An oxyalkylene group or an oxystyrene group, p is a number of 0 or 1, q is a number of 0 to 2, r is an average added mole number of AO, a number of 3 to 50, R ⁴ is a hydrogen atom or a carbon number of 1 Represents an alkyl group of ˜18. ]

[Wherein R ¹¹ is a hydrogen atom or a methyl group, R ¹² is an alkylene group having 2 to 12 carbon atoms, m1 is a number of 1 to 30, M ³ and M ⁴ are a hydrogen atom, an alkali metal or an alkaline earth metal, respectively. Represents. ]

[Wherein R ¹³ and R ¹⁵ are each a hydrogen atom or a methyl group, R ¹⁴ and R ¹⁶ are each an alkylene group having 2 to 12 carbon atoms, m2 and m3 are each a number of 1 to 30 and M ⁵ is Represents a hydrogen atom, an alkali metal or an alkaline earth metal. ] The concrete composition according to claim 1, wherein the weight of the hydraulic powder per 1 m ³ is 190 to 420 kg / m ³ .   The concrete composition according to claim 1 or 2, wherein the water / hydraulic powder ratio is 45 to 70% (weight ratio).   The concrete composition according to any one of claims 1 to 3, wherein the slump immediately after kneading is 6 to 23 cm. Monomer 1 represented by the following general formula (1), monomer 2 represented by the following general formula (2), and monomer 3 represented by the following general formula (3) are copolymerized A concrete additive (A) containing a phosphate ester polymer having a weight average molecular weight of 10,000 to 40,000, a hydraulic powder (B), and an aggregate. mixed with (C) and water (D), 1 m ³ water per are 170~185kg / m ^3, 1m ³ per paste volume (volume of water and hydraulic powder) is at 250~320L / m ³ A method for producing a concrete composition, comprising producing a concrete composition having a slump of 6 to 23 cm.

[In the formula, R ¹ and R ² are each a hydrogen atom or a methyl group, R ³ is a hydrogen atom, or — (CH ₂ ) _q (CO) _p O (AO) _r R ⁴ , and AO has 2 to 4 carbon atoms. An oxyalkylene group or an oxystyrene group, p is a number of 0 or 1, q is a number of 0 to 2, r is an average added mole number of AO, a number of 3 to 50, R ⁴ is a hydrogen atom or a carbon number of 1 Represents an alkyl group of ˜18. ]

[Wherein R ¹¹ is a hydrogen atom or a methyl group, R ¹² is an alkylene group having 2 to 12 carbon atoms, m1 is a number of 1 to 30, M ³ and M ⁴ are a hydrogen atom, an alkali metal or an alkaline earth metal, respectively. Represents. ]

[Wherein R ¹³ and R ¹⁵ are each a hydrogen atom or a methyl group, R ¹⁴ and R ¹⁶ are each an alkylene group having 2 to 12 carbon atoms, m2 and m3 are each a number of 1 to 30 and M ⁵ is Represents a hydrogen atom, an alkali metal or an alkaline earth metal. ]