JP2007131520A - Cement admixture - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cement admixture capable of enhancing slump maintainability, maintaining fluidity, and obtaining an appropriate viscosity which provides an easy workability at the place where a cement composition or the like is handled. <P>SOLUTION: The cement admixture comprises an alkylene oxide adduct consisting of a compound having 3 or more active hydrogens to which an oxyalkylene group is added, wherein an average molar number of addition of the oxyalkylene group vs. 1 mole of the active hydrogen is 100 moles or more. In addition, the cement admixture comprises a carboxylic acid-based polymer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a cement admixture. More specifically, the present invention relates to a cement admixture that can be suitably used for cement compositions such as cement paste, mortar, and concrete.

Cement admixture is widely used as a water reducing agent for cement compositions such as cement paste, mortar, and concrete, and is indispensable for building civil engineering and building structures from cement compositions. It has become. Such a cement admixture has the effect of improving the strength, durability, and the like of the cured product by increasing the fluidity of the cement composition and reducing the water content of the cement composition. Among such water reducing agents, those containing a polycarboxylic acid polymer exhibit high water reducing performance as compared with conventional water reducing agents such as naphthalene, and thus have many achievements as high performance AE water reducing agents.

In such a cement admixture, in addition to the water reducing performance for the cement composition, there is a demand for a cement admixture whose viscosity can be improved so that it is easy to work at the site where the cement composition is handled. In other words, the cement admixture used as a water reducing agent will exhibit water reducing performance by lowering the viscosity of the cement composition, but it will exhibit such performance and make it easier to work at the site where it is handled. What can be made to have a high viscosity is required in the production site of civil engineering and building structures. When the cement admixture exhibits such performance, work efficiency and the like in construction of civil engineering and building structures will be improved.

By the way, with respect to the dispersant for inorganic powders, those containing a water-soluble cocondensate or water-soluble polymer as an essential component into which a random polymer chain of oxypropylene group and / or oxybutylene group and oxyethylene group is introduced. (For example, refer to Patent Document 1).
In addition, a polyoxyalkylene compound obtained by adding an alkylene oxide to a polyalkylene polyamine has an excellent cement dispersion effect, cement dispersion assist effect, etc., and a high performance AE water reducing agent comprising a polycarboxylic acid having a polyalkylene glycol chain is added to this. It is disclosed that the blended cement composition has an excellent water reduction effect (for example, see Patent Document 2).

However, when it is used for a cement composition or the like, it is not sufficient that water is reduced. In other words, 1) work on construction sites such as civil engineering and building structures by improving the fluidity retention of concrete, etc. at the production site, and 2) making concrete, etc. easier to work. There was room for improvement, such as further improving efficiency.
Japanese Patent Laid-Open No. 9-248438 (page 2) JP 2000-109357 A (page 2)

The present invention has been made in view of the above-described situation, and it is intended to maintain fluidity while enhancing slump retainability, and to make the viscosity easy to work in the field where cement compositions are handled. It is intended to be able to.

The present inventors further provide a cement admixture required in the construction site of civil engineering / building structures, etc. that can form a cement composition etc. with excellent fluidity and excellent workability. investigated. First, paying attention to the ability of the polycarboxylic acid polymer to exhibit water-reducing performance against cement compositions, etc., an oxyalkylene group is added to a compound having 3 or more active hydrogens together with the polycarboxylic acid polymer. By using the added alkylene oxide adduct, it is possible to maintain the high dispersibility or water reduction of the polycarboxylic acid polymer by delaying the adsorption of the polycarboxylic acid polymer to the cement due to its steric hindrance. It has been found that the fluidity is maintained while enhancing the retainability and is effective in improving the viscosity of the cement composition and the like. Of the alkylene oxide adducts obtained by adding an oxyalkylene group to a compound having 3 or more active hydrogens, an oxyalkylene group is added to a compound having 3 or more active hydrogens having at least 100 moles of oxyalkylene groups. The added alkylene oxide adduct further increases the steric hindrance and controls the adsorption rate of the polycarboxylic acid polymer, so that the fluidity is maintained while enhancing the slump retention, and the viscosity of the cement composition and the like is increased. It has been found that improvement is possible, and the present invention has been achieved.

That is, the present invention is a cement admixture comprising an alkylene oxide adduct obtained by adding an oxyalkylene group to a compound having 3 or more active hydrogens, wherein the alkylene oxide adduct contains an oxyalkylene group per mole of active hydrogen. This cement admixture has a total average added mole number of 100 mol or more.
The present invention is also a cement admixture comprising an alkylene oxide adduct obtained by adding an oxyalkylene group to a compound having 3 or more active hydrogens and a sulfonic acid compound.
The present invention is described in detail below.

An alkylene oxide adduct obtained by adding an oxyalkylene group to a compound having three or more active hydrogens may be referred to as an alkylene oxide adduct (X) or an adduct (X) below. In addition, in the said alkylene oxide adduct (X) or adduct (X), "(X)" is a polyalkyleneimine alkylene oxide adduct (A) which is a subordinate concept, a polyhydric alcohol alkylene oxide adduct ( A ′) and the thioalcohol alkylene oxide adduct (A ″) for ease of distinction. In the present specification, unless otherwise specified, the alkylene oxide adduct, and , And adduct mean the alkylene oxide adduct (X) or the adduct (X), respectively.

The compound having 3 or more active hydrogens is a compound having 3 or more active hydrogen groups in the molecule. Examples of the compound having three or more active hydrogen groups in the molecule include polyhydric alcohols having three or more hydrogen atoms derived from a hydroxyl group (—OH), hydrogen atoms derived from an amino group or a secondary amine group. Three or more amines and thioalcohols having three or more hydrogen atoms derived from a thiol group (—SH) are suitable, and one or more of these can be used.

One of the preferred embodiments of the present invention is that the alkylene oxide adduct is a product obtained by adding an alkylene oxide to a polyhydric alcohol and / or polyethyleneimine.
The total average number of moles of oxyalkylene group added per mole of active hydrogen is the number of active hydrogen groups added to 1 mole of active hydrogen group possessed by a compound having three or more active hydrogens that will form adduct (X). Means the average number of moles of the oxyalkylene group. For example, it can be calculated by the following formula.
Total average number of moles of oxyalkylene groups added per mole of active hydrogen = [total number of moles of oxyalkylene groups added to the active hydrogen group of adduct (X)] / [3 or more of the above active hydrogens The total number of moles of active hydrogen groups possessed by the compound possessed]

It is also a preferred embodiment of the present invention that the cement admixture is a cement admixture further comprising a polycarboxylic acid polymer.
Details and technical significance of the above-described embodiment will be described later together with a description of the polyalkyleneimine alkylene oxide adduct (A), which is a subordinate concept of the adduct (X). The details and technical significance of the embodiment using the polycarboxylic acid-based polymer are not limited to the polyalkyleneimine alkylene oxide adduct (A), but also to the adduct (X) which is a superordinate concept. Can be applied as is.
The polycarboxylic acid polymer is represented by the following general formula (1);

(In the general formula ^(1), R 1, ^{R 2} and ^{R 3} are the same or different, .R ⁴ represents a hydrogen atom or a methyl group, one or oxyalkylene group having 2 to 4 carbon atoms R ⁵ represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, x represents a number of 0 to 2, y represents a number of 0 to 1, m represents oxy This represents the average number of moles added of the alkylene group, and is a number from 1 to 300.)
A monomer unit derived from a polyalkylene glycol unsaturated monomer represented by the following general formula (2);

(In the general formula (2), R ⁶ and R ⁷ are the same or different and each represents a hydrogen atom or a methyl group. M ¹ represents a hydrogen atom, a metal atom, an ammonium group, or an organic amine group.)
It is also a preferred embodiment of the present invention that the cement admixture essentially comprises a monomer unit derived from an unsaturated monocarboxylic acid monomer represented by the formula:
As the metal atom in M ¹ of the general formula (2), a monovalent metal atom such as an alkali metal atom such as lithium, sodium or potassium; a divalent metal atom such as an alkaline earth metal atom such as calcium or magnesium; A trivalent metal atom such as aluminum or iron is preferred. Moreover, as an organic amine group, alkanolamine groups, such as an ethanolamine group, a diethanolamine group, and a triethanolamine group, and a triethylamine group are suitable. Further, it may be an ammonium group. As such an unsaturated monocarboxylic acid monomer, acrylic acid, methacrylic acid, crotonic acid and the like; monovalent metal salts, divalent metal salts, ammonium salts, and organic amine salts thereof are suitable. Among these, methacrylic acid; its monovalent metal salt, divalent metal salt, ammonium salt, and organic amine salt are preferably used from the viewpoint of improving cement dispersion performance, and the unsaturated carboxylic acid monomer (b) It is suitable as.

The polycarboxylic acid polymer may be referred to as a polycarboxylic acid polymer (B). In the polycarboxylic acid polymer (B), “(B)” is a mere symbol. The use form and technical significance of the polycarboxylic acid polymer (B) will be described in the description of the polyalkyleneimine alkylene oxide adduct (A) described later, but the adduct (X ) As it is.

One of the preferred embodiments of the present invention is that the polycarboxylic acid-based polymer contains 50% by mass or more of unsaturated monocarboxylic acid-based monomer in 100% by mass of all components of the carboxylic acid-based monomer. It is.
The unsaturated monocarboxylic acid monomer has one carboxyl group per molecule. On the other hand, since polyvalent carboxylic acid monomers such as maleic acid have two or more carboxyl groups in one molecule, the amount of carboxyl groups in the polymer increases when used for polymer synthesis. As a result, the number of adsorbing groups on the cement particles increases. Since the copolymer constituting the cement admixture of the present invention exerts its effect by controlling the adsorption rate to cement particles, if the number of adsorbing carboxyl groups increases too much, the dispersion force increases. Therefore, there is a possibility that the expression of the slump retention characteristic of the present invention is not sufficiently exhibited.
In addition, since polyvalent carboxylic acid monomers such as maleic acid have almost no homopolymerization, it depends on the polymerization of the polyalkylene glycol monomer in order to improve the polymerization rate. For this reason, it is difficult to freely change the amount of the polyvalent carboxylic acid monomer used for the synthesis of the polymer, and it is preferable to limit the amount of the polyvalent carboxylic acid monomer. For example, if the amount of the polyvalent carboxylic acid monomer is decreased in order to lower the dispersibility, the residual monomer of the polyalkylene glycol monomer increases, and the use of the polymer does not increase. Defects such as excessive increase in volume are born. Therefore, it is preferable to reduce the amount of the polyvalent carboxylic acid monomer having two or more adsorbing groups as much as possible.
Therefore, in the preparation of the polycarboxylic acid polymer, the unsaturated monocarboxylic acid monomer is mainly used, that is, the unsaturated monocarboxylic acid monomer in 100% by mass of all components of the carboxylic acid monomer. When the content is 50% by mass or more, further excellent effects can be obtained. The unsaturated monocarboxylic acid monomer is preferably 70% by mass or more in 100% by mass of all the carboxylic acid monomer components. More preferably, it is 80% by mass or more, further preferably 90% by mass or more, particularly preferably 95% by mass or more, and most preferably substantially all of the carboxylic acid monomer is not present. It is a saturated monocarboxylic acid monomer.

The present invention is also a cement admixture comprising an alkylene oxide adduct obtained by adding an oxyalkylene group to a compound having three or more active hydrogens and a sulfonic acid compound.
Hereinafter, the sulfonic acid compound may be referred to as a sulfonic acid compound (C). In the sulfonic acid compound (C), “(C)” is merely a symbol. The use form and technical significance of the sulfonic acid compound (C) will be described in the description of the polyalkyleneimine alkylene oxide adduct (A) described later. Can also be applied as is.

One of the preferred embodiments of the present invention is that the compound having three or more active hydrogens has a hydroxyl group and / or an amino group having active hydrogen.
By becoming the said embodiment, a suitable oxyalkylene group can be added to the compound which has the said active hydrogen 3 or more.

One of the preferred embodiments of the present invention is that the alkylene oxide adduct essentially comprises an oxyalkylene group having 3 or more carbon atoms.
The alkylene oxide adduct having the above-described form has a highly hydrophobic oxyalkylene group having 3 or more carbon atoms, and due to this structure, it is excellent in water reduction and excellent in low viscosity.

One of the preferred embodiments of the present invention is that the oxyalkylene group, which is a structural unit of the alkylene oxide adduct, is derived from ethylene oxide and propylene oxide.
The alkylene oxide adduct preferably has an oxyalkylene chain composed of two or more oxyalkylene groups. Among the alkylene oxide adducts having an oxyalkylene chain composed of two or more oxyalkylene groups, the alkylene oxide adduct having the above form is more preferable.
The oxyalkylene chain composed of the two or more oxyalkylene groups preferably has a so-called PQP type block copolymer structure. More preferably, in such a structure, P is an oxyethylene group and Q is an oxyalkylene group having 3 or more carbon atoms. In such a PQP-type structure, a highly hydrophobic oxyalkylene group having 3 or more carbon atoms (site represented by Q) is located inside a highly hydrophilic oxyethylene chain (site represented by P). ) Exist, and due to this structure, it is excellent in water reduction and excellent in low viscosity. More preferably, in the above structure, P is an oxyethylene group and Q is an oxypropylene group, whereby it is possible to more fully exhibit both the effects of water reduction and low viscosity. . Particularly preferred is a form having such a structure and the end of the adduct (X) being an oxyethylene group. Note that P and Q are merely symbols.

Although the weight average molecular weight of the said adduct (X) is not specifically limited, It is preferable that it is 500-500000. The lower limit of the weight average molecular weight is more preferably 1000 or more, still more preferably 5000 or more, particularly preferably 8000 or more, and most preferably 10,000 or more. The upper limit of the weight average molecular weight is more preferably 400000 or less, still more preferably 300000 or less, particularly preferably 200000 or less, and most preferably 150,000 or less. In addition, as a value of the weight average molecular weight of the said adduct (X), the value measured by GPC on the following measuring conditions shall be employ | adopted. In the measurement of the weight average molecular weight of the adduct (X), values measured under the following measurement conditions are adopted.

Analytical conditions and columns used: TSK guard column α + TSKgel 1 α-5000 + TSKgel α-4000 + TSKgel α-3000, one by one connected and used eluent: sodium dihydrogen phosphate · 2H ₂ O: 62.4 g, disodium hydrogen phosphate · _12H 2 O143.3g deionized water: acetonitrile solution prepared by dissolving 7794.3G: using mixed solution of 2000 g.
Detector: Viscotek's triple detector Model 302
Light scattering detector: right angle light scattering: 90 ° scattering angle, low angle light scattering: 7 ° scattering angle, cell capacity: 18 μL, wavelength: 670 nm
RI detector: cell capacity: 12 μL, wavelength: 660 nm
Standard sample: Polyethylene glycol SE-8 (Mwl07000) manufactured by Tosoh Corporation was used, the dn / dC was 0.135 ml / g, and the refractive index of the used eluent was determined to be 1.333, and the apparatus constant was determined.
Injection amount Standard sample: 100 μL of the solution dissolved in the eluent so that the polymer concentration becomes 0.2 vol% Sample: The solution dissolved in the eluent so that the polymer concentration becomes 1.0 vol% 100 μL injection / flow rate: 0.8 ml / min
-Column temperature: 40 ° C

The cement admixture is a cement admixture comprising a polyalkyleneimine alkylene oxide adduct (A), and the polyalkyleneimine alkylene oxide adduct (A) is a total average addition of oxyalkylene groups as constituent units. One of the preferred embodiments of the present invention is that the number of moles is 100 moles or more based on the active hydrogen derived from amine.
The above polyalkyleneimine alkylene oxide adduct (hereinafter sometimes referred to as polyalkyleneimine alkylene oxide adduct (A) or simply adduct (A)) will be described below. The details and technical significance of the embodiment of the adduct (A) to be described later can be appropriately applied to the adduct (X), which is a superordinate concept of the adduct (A).

The cement admixture comprises (1) a form containing a polyalkyleneimine alkylene oxide adduct (A) having an average addition mole number of oxyalkylene groups of 100 moles or more, and (2) an average addition mole number of oxyalkylene groups of 100 moles. A form containing the above polyalkyleneimine alkylene oxide adduct (A) and polycarboxylic acid polymer (B), (3) polyalkyleneimine alkylene oxide adduct having an average addition mole number of oxyalkylene groups of 100 mol or more ( A) a form containing sulfonic acid compound (C), (4) polyalkyleneimine alkylene oxide adduct (A) having an average addition mole number of oxyalkylene groups of 100 mol or more, polycarboxylic acid polymer (B) And at least one of the four forms including the sulfonic acid compound (C)
In these forms, the polyalkyleneimine alkylene oxide adduct (A), polycarboxylic acid polymer (B), and sulfonic acid compound (C) having an average addition mole number of oxyalkylene groups of 100 mol or more are: You may use 1 type (s) or 2 or more types, respectively. Two or more polyalkyleneimine alkylene oxide adducts (A) are used, for example, if the average addition mole number of oxyalkylene groups and the content of oxyalkylene groups having 3 or more carbon atoms are different. Means that Two or more types of polycarboxylic acid polymers (B) mean that two or more types are used if the characteristics such as average molecular weight and average number of added moles of alkylene oxide are different. .

In the following description, these components in the present invention are referred to as polyalkyleneimine alkylene oxide adduct (A) (also simply referred to as adduct (A)); polyalkylene having an oxyalkylene group having 3 or more carbon atoms as essential. Imine ethylene oxide adduct (A1) (also simply referred to as adduct (A1)); polyalkyleneimine alkylene oxide adduct (A2) having an average addition mole number of oxyalkylene groups of 100 mol or more (also simply referred to as adduct (A2)) ); Polyalkyleneimine alkylene oxide adduct (A3) (also simply referred to as adduct (A3)) having an average addition mole number of oxyalkylene groups of 100 moles or more and an oxyalkylene group having 3 or more carbon atoms as an essential component; Polycarboxylic acid polymer (B) (also referred to simply as polymer (B)); polyalkyleneiminal A polycarboxylic acid polymer (B1) (also simply referred to as a polymer (B1)) obtained by copolymerizing a lenoxide adduct monomer; and a polyalkylene glycol side chain essentially comprising an oxyalkylene group having 3 or more carbon atoms. Polycarboxylic acid polymer (B2) (also simply referred to as polymer (B2)); polycarboxylic acid polymer (B3) other than the above polymer (B1) and polymer (B2) (simply polymer (B3 Also called)).
The polyalkyleneimine alkylene oxide adduct monomer means a polyalkyleneimine alkylene oxide adduct having a polymerizable unsaturated double bond.
In the above components, the adduct (A) is an adduct that is a superordinate concept of the adduct (A1), the adduct (A2), and the adduct (A3), and the adduct (A1), adduct (A2), and The adduct (A3) is included in the adduct (A). Similarly, the polymer (B1), the polymer (B2), and the polymer (B3) are included in the adduct (B).

In the present invention, the cement admixture of the above form (1) includes a polyalkyleneimine alkylene oxide adduct (A) having an average addition mole number of oxyalkylene groups of 100 mol or more, that is, an adduct (A2). In addition to the form using only the adduct (A2), for example,
A combination of adduct (A2) + adduct (A),
A combination of adduct (A3) + adduct (A),
A combination of adduct (A2) + adduct (A1),
Combination with adduct (A3) + adduct (A1),
A combination of adduct (A2) + adduct (A3) + adduct (A),
The form etc. which are used in combination with an adduct (A2) + adduct (A3) + adduct (A1) are mentioned.
These combinations are preferred forms of the present invention, but more preferably, the form in which the adduct (A2) or adduct (A3) is used alone, and still more preferably, the adduct (A3) is used alone. It is a form.

The cement admixture of the above form (2) is a form containing an adduct (A2) and a polycarboxylic acid polymer (B).
Combination with adduct (A3) + polymer (B1),
Combination with adduct (A3) + polymer (B2),
Combination with adduct (A3) + polymer (B3),
A combination of adduct (A3) + polymer (B1) + polymer (B3),
Combinations of adduct (A3) + polymer (B2) + polymer (B3) and the like can be mentioned.

Further, the cement admixtures of the above forms (3) and (4) are cement admixtures further containing a sulfonic acid compound in the form (1) and form (2), respectively, and the form (1) described above. The combinations exemplified in the form (2) can be applied as they are.

In the cement admixture of the above-mentioned form (1), it is appropriate to add 30% by mass or more of the adduct (A2) with respect to 100% of the solid content of the cement admixture. If it is less than 30%, the dispersibility or water-reducing property is remarkably lowered and the desired fluidity cannot be obtained. More preferably, it is 50% or more, More preferably, it is 70% or more, Most preferably, it is 80% or more.

In the cement admixture of the above form (2), it is appropriate to blend 5% by mass or more of the adduct (A2) with respect to 100% of the solid content of the cement admixture. If it is less than 5%, the slump retention cannot be improved. More preferably, it is 10% or more, further preferably 20% or more, and particularly preferably 30% or more. Further, the use ratio of the adduct (A2) and the polycarboxylic acid polymer (B) is preferably 5/95 to 95/5% by mass. More preferably, it is 10 / 90-90 / 10 mass%, More preferably, it is 20 / 80-80 / 20 mass%, Especially preferably, it is 30 / 70-70 / 30 mass%.

In the cement admixture of the above form (3), it is appropriate to add 10% by mass or more of the adduct (A2) with respect to 100% of the solid content of the cement admixture. If it is less than 10%, the slump retention cannot be improved. More preferably, it is 20% or more, further preferably 30% or more, and particularly preferably 40% or more. Further, it is appropriate to blend 5% by mass or more of the sulfonic acid compound (C) with respect to 100% of the solid content of the cement admixture. More preferably, it is 10% or more, further preferably 20% or more, and particularly preferably 30% or more. Furthermore, the use ratio of the adduct (A2) and the sulfonic acid compound (C) is preferably 5/95 to 95/5 mass%. More preferably, it is 10 / 90-90 / 10 mass%, More preferably, it is 20 / 80-80 / 20 mass%, Especially preferably, it is 30 / 70-70 / 30 mass%.

In the cement admixture of the above form (4), it is appropriate to add 5% by mass or more of the adduct (A2) with respect to 100% of the solid content of the cement admixture. If it is less than 5%, the slump retention cannot be improved. More preferably, it is 10% or more, More preferably, it is 15% or more, Most preferably, it is 20% or more. Further, it is appropriate to blend 5% by mass or more of the polycarboxylic acid polymer (B) with respect to 100% of the solid content of the cement admixture. If it is less than 5%, the dispersibility or water reducing property is remarkably lowered, and the desired fluidity cannot be obtained. More preferably, it is 10% or more, More preferably, it is 15% or more, Most preferably, it is 20% or more. Furthermore, it is appropriate to blend 5% by mass or more of the sulfonic acid compound (C) with respect to 100% of the solid content of the cement admixture. More preferably, it is 10% or more, further preferably 20% or more, and particularly preferably 30% or more.

In the cement admixtures of the above forms (1) to (4), in the adduct (A), the average addition mole number of the oxyalkylene group is 100 mol or more. )) Is essential. If it is less than 100 moles, the absolute molecular weight becomes small and steric hindrance cannot be imparted sufficiently, so that there is a possibility that the slump retention property cannot be improved.

Further, in the adduct (A), the oxyalkylene group preferably has 3 or more carbon atoms (addition (A1) or (A3)). When the compound having 3 or more carbon atoms is contained, the softening point of the polyalkyleneimine alkylene oxide adduct (A) can be lowered, so that the fluidity of the cement composition can be improved and the effect on slump retention is also expected. can do. The content ratio of the oxyalkylene group having 3 or more carbon atoms is such that the oxyalkylene group having 3 or more carbon atoms is based on 100% by mass of the total amount of oxyalkylene groups in the polyalkyleneimine alkylene oxide adduct (A). It is suitable that it is 1 mass% or more. 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% or more. Moreover, it is suitable that it is 90 mass% or less. If it exceeds 90% by mass, the hydrophobicity becomes too high, it becomes difficult to dissolve in water, and sufficient dispersibility may not be exhibited. More preferably, it is 80 mass% or less, Especially preferably, it is 70 mass% or less, Most preferably, it is 60 mass% or less.

In the adduct (A), the oxyalkylene group having 3 or more carbon atoms is preferably an oxypropylene group, and the oxyalkylene group having 3 or more carbon atoms is also an oxypropylene group. Is one of the preferred forms of cement admixture.
The adduct (A) preferably also has an oxyethylene group as an essential component, whereby the hydrophilicity of the cement admixture is further improved and the dispersibility can be more fully exhibited. More preferably, both an oxypropylene group and an oxyethylene group are essential. More preferably, as described later, a so-called PQP type (P: This is a form having a block copolymer structure of (oxyethylene group, Q: oxypropylene group).

In the present invention, the following method is suitable as a method for measuring the solid content of the cement admixture.
(Solid content measurement method)
1. Weigh the aluminum dish.
The solid content to be measured is precisely weighed on the aluminum dish precisely weighed in 2.1.
3. A solid content measurement product precisely weighed in 2 is placed in a dryer adjusted to 130 ° C. in a nitrogen atmosphere for 1 hour.
4. After 1 hour, remove from the dryer and allow to cool in a desiccator at room temperature for 15 minutes.
5. After 15 minutes, remove from the desiccator and precisely weigh the aluminum dish and the measurement object.
The mass of the aluminum dish obtained in 1 is subtracted from the mass obtained in 6.5, and the solid content is measured by dividing the mass of the fixed part obtained in 2.

In addition, as a method for measuring the solid content ratio of the adduct (A) to the solid content of the cement admixture and a method of measuring the solid content ratio of the polymer (B) to the solid content of the cement admixture, the following methods are preferable. It is.
1. A 20% by mass paratoluenesulfonic acid aqueous solution is added to a cement admixture aqueous solution whose solid content is adjusted to 20% by mass to adjust to pH 2.0.
The mixture prepared in 2.1 is adjusted to 85 ° C. and allowed to stand for 1 hour.
3. After confirming that the mixture is separated into two layers, the mixture is separated into a supernatant and a precipitate.
4). The supernatant is concentrated, the amount of paratoluenesulfonic acid is quantified by liquid chromatography, and the amount of adduct (A) is obtained by subtracting the amount of paratoluenesulfonic acid from the weight of the supernatant. By dividing the mass of the obtained adduct (A) by the weight of the cement admixture used in 1, the solid content ratio of the adduct (A) is measured.
An equal amount of water is added to the precipitate obtained in 5.3, the temperature is adjusted to 85 ° C., and the mixture is allowed to stand for 1 hour.
6). After confirming that the mixture is separated into two layers, the mixture is separated into a supernatant and a precipitate.
7). The supernatant is concentrated, the amount of paratoluenesulfonic acid is quantified by liquid chromatography, and the amount of paratoluenesulfonic acid is subtracted to obtain the mass of the polymer (B). The solid content ratio of the polymer (B) is measured by dividing the mass of the obtained polymer (B) by the mass of the cement admixture used in 1.

As a method for producing the cement admixture of the present invention, a cement admixture comprising the adduct (A2) and the polycarboxylic acid polymer (B) is produced as long as it is the cement admixture of the above form (2). Moreover, if it is a cement admixture of the said form (3), it will manufacture the cement admixture containing an adduct (A2) and a sulfonic acid type compound (C), and also the said form ( If it is a cement admixture of 4), a cement admixture comprising an adduct (A2), a polycarboxylic acid polymer (B) and a sulfonic acid compound (C) will be produced. Is not particularly limited. For example, it is preferable that the adduct (A), the polycarboxylic acid polymer (B), and the sulfonic acid compound (C) are respectively prepared and mixed. The polymerization method and the like are as described later.

Hereinafter, the polyalkyleneimine alkylene oxide adduct (A), (A1) to (A3) polycarboxylic acid copolymers (B), (B1) to (B3), and the sulfonic acid compound (C) in the present invention will be further described. explain. The polyalkyleneimine alkylene oxide adduct (A) may or may not have a polymerizable unsaturated double bond. These may be used in combination. As the adduct (A) having no polymerizable unsaturated double bond, a compound obtained by adding an alkylene oxide to the nitrogen atom of the amino group or imino group of the polyalkyleneimine is suitable. The nitrogen atom of the amino group or imino group to which alkylene oxide is added has an active hydrogen atom.

As said polyalkylene imine, 1 type (s) or 2 or more types of C2-C8 alkylene imines, such as ethyleneimine, propyleneimine, 1,2-butyleneimine, 2,3-butyleneimine, 1,1-dimethylethyleneimine Homopolymers and copolymers of these alkyleneimines obtained by polymerizing the above by a conventional method are preferred. These may be used alone or in combination of two or more. Such a polyalkyleneimine forms the polyalkyleneimine chain of the adduct (A). The polyalkyleneimine chain has a linear structure, a branched structure, and a three-dimensional structure. Any of the crosslinked structures may be used. Furthermore, ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine and the like may be used. Such a polyalkyleneimine usually has a primary amino group having an active hydrogen atom or a secondary amino group (imino group) in addition to a tertiary amino group in the structure.

The adduct (A) may be an adduct (A1) or adduct (A3) as long as the average addition mole number of the oxyalkylene group is 100 mol or more as in the adduct (A2) or adduct (A3). It is particularly preferable that at least one oxyalkylene group having 3 or more carbon atoms has at least one kind. When two or more types of oxyalkylene groups are present in the same adduct, the oxyalkylene group may take any form such as random addition, block addition, and alternate addition, but a form obtained by block addition is more preferable. . The structure of the adduct (A1) or the adduct (A3) essentially including such an oxyalkylene group may have at least one oxyalkylene group having 3 or more carbon atoms, such as ethylene oxide, In addition to alkylene oxides having 2 to 8 carbon atoms such as propylene oxide, butylene oxide, isobutylene oxide, 1-butene oxide, 2-butene oxide, trimethylethylene oxide, tetramethylene oxide, tetramethylethylene oxide, butadiene monooxide, octylene oxide, Aliphatic epoxides such as dipentane ethylene oxide and dihexane ethylene oxide; Alicyclic epoxides such as trimethylene oxide, tetramethylene oxide, tetrahydrofuran, tetrahydropyran and octylene oxide; De, it is preferable that a structure formed by one or more aromatic epoxides such as 1,1-diphenyl ethylene oxide. In particular, when an adduct composed of ethylene oxide and propylene oxide or an adduct composed of ethylene oxide and butylene oxide is used as a cement admixture, the balance of water reduction, slump retention, and air volume reduction effects of the cement composition Is a preferred combination.

With regard to the oxyalkylene group, a preferred form of the adduct (A1) or (A3) is a form in which two or more oxyalkylene groups are present and these are added as a block. That is, the adduct (A1) or (A3) has an oxyalkylene chain composed of two or more oxyalkylene groups, and the oxyalkylene chain has a so-called PQP type block copolymer structure. It is suitable. More preferably, in such a structure, P is an oxyethylene group and Q is an oxyalkylene group having 3 or more carbon atoms. In such a PQP type structure, a highly hydrophobic oxyalkylene group having 3 or more carbon atoms (site represented by Q) is located inside a highly hydrophilic oxyethylene chain (site represented by P). ) Exist, and due to this structure, it is excellent in water reduction and excellent in low viscosity. More preferably, in the above structure, P is an oxyethylene group and Q is an oxypropylene group, whereby it is possible to more fully exhibit both the effects of water reduction and low viscosity. . Particularly preferred is a form having such a structure and the end of the adduct (A1) or (A3) being an oxyethylene group. Such a form is the adduct (A1) or (A3). It is also a particularly preferred form.

The adduct (A) has a polyalkyleneimine chain, and the polyalkyleneimine chain is preferably formed mainly of ethyleneimine. In this case, “mainly” means that when the polyalkyleneimine chain is formed of two or more kinds of alkyleneimines, it occupies most of the total number of moles of alkyleneimines. In the present invention, the alkyleneimine that forms a polyalkyleneimine chain is mostly composed of ethyleneimine, so that the hydrophilicity of the adduct (A) is improved and the effects are sufficiently exerted. The use of ethyleneimine as an alkyleneimine that forms a polyalkyleneimine chain to such an extent that the above-described effects can be fully exerted means that the above-mentioned "occupies the majority", so that it can be the "main" It becomes.
In the alkyleneimine that forms the polyalkyleneimine chain, the expression “occupying the majority” in terms of mol% of ethyleneimine in 100 mol% of all alkyleneimine is preferably 50 to 100 mol%. If it is less than 50 mol%, the hydrophilicity of the polyalkyleneimine chain may be lowered. 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. In the adduct (A), the average polymerization number of alkyleneimine per polyalkyleneimine chain is preferably 2 or more, and more preferably 300 or less. If it is less than 2, the function of the adduct (A) may not be sufficiently exhibited, and if it exceeds 300, the polymerizability of the adduct (A) may be reduced. Particularly preferably, it is 3 or more. More preferably, it is 200 or less, More preferably, it is 100 or less, Especially preferably, it is 75 or less, Most preferably, it is 50 or less. The average polymerization number of diethylenetriamine is 2, and the average polymerization number of triethylenetetramine is 3.

In the adduct (A), the average addition mole number of the oxyalkylene group is preferably more than 0 and 500 or less. If it exceeds 500, the polymerizability of these monomers may decrease. More preferably, it is 450 or less, More preferably, it is 400 or less, Especially preferably, it is 350 or less, Most preferably, it is 300 or less. Further, it is more preferably 50 or more, further preferably 70 or more, particularly preferably 90 or more, and most preferably 100 or more. If the average addition mole number of the oxyalkylene group in the adduct (A) is out of such a range, there is a possibility that the effect of making the fluidity of the cement composition or the like excellent will not be sufficiently exhibited. The average added mole number means the average value of the number of moles of the oxyalkylene group added to one mole of active hydrogen group of the polyalkyleneimine that forms the adduct (A). To do. When two or more of the above adducts (A) are used, at least one of the adducts may have an average addition mole number of the oxyalkylene group of 100 moles or more, and one or two or more, the average addition mole of the oxyalkylene group. The number may be 100 mol or less, and may be outside the above-mentioned range. The average addition mole number of the oxyalkylene group in this case is, for example, the above adduct (A) having an average addition mole number of oxyalkylene group of 200 mol and the above adduct having an average addition mole number of oxyalkylene group of 50 mol ( The average addition mole number of the oxyalkylene group when A) is used at 50/50% by mass is 125 mol, and the average addition mole number of the oxyalkylene group is similarly 80 mol when used at 20/80% by mass. It becomes.

As a weight average molecular weight of the said adduct (A), it is preferable that it is 5000 or more, and it is preferable that it is 1000000 or less. More preferably, it is 10,000 or more, More preferably, it is 15000 or more, Most preferably, it is 20000 or more. Further, it is more preferably 700,000 or less, further preferably 500,000 or less, and particularly preferably 300,000 or less. When two or more kinds of the adducts (A) are used, the weight average molecular weight when all of them are mixed may be in the above-described range, or one or more kinds may be outside the above-described range. .

The adduct (A) has a block copolymer structure of PQP type (P: oxyethylene group, Q: oxypropylene group), as described above, and the adduct as described above. The terminal of (A) is an oxyethylene group. As an adduct (A) of this form, for example, ethylene oxide is first added to polyethyleneimine, and then propylene oxide and ethylene oxide are added in this order. It is suitable that it is obtained by making it.

In such an adduct (A), the average polymerization number of alkyleneimine per polyethyleneimine chain used and the average addition mole number of ethylene oxide or propylene oxide are as described above, but are particularly suitable. As a form, the average number of polymerizations of alkyleneimine per polyethyleneimine chain used is 5 to 50, the number of moles of ethylene oxide added to polyethyleneimine is 3 to 300, and propylene oxide to be added to the ethylene oxide The number of moles added is 3 to 200, and the number of moles added of the terminal ethylene oxide is 3 to 300. Most preferably, it is the form which is 10-45, 3-200, 3-100, 3-200 in order, respectively.

The adduct (A1) is not particularly limited as long as it is the adduct (A) essentially including an oxyalkylene group having 3 or more carbon atoms. Moreover, as said adduct (A2), what is necessary is just the said adduct (A) whose average addition mole number of an oxyalkylene group is 100 mol or more, and is not specifically limited. Further, as the adduct (A3), an oxyalkylene group having 3 or more carbon atoms is essential, and the adduct (A) having an average addition mole number of the oxyalkylene group of 100 mol or more may be used. Is not to be done.

The polycarboxylic acid polymer (B) is obtained by copolymerizing a monomer component essentially comprising a polyalkylene glycol unsaturated monomer (a) and an unsaturated monocarboxylic acid monomer (b). Is preferred. More preferably, a monomer component containing 1 to 99% by mass of the polyalkylene glycol-based unsaturated monomer (a) and 99 to 1% by mass of the unsaturated monocarboxylic acid monomer (b) is copolymerized. More preferably, the monomer component containing 40 to 97% by mass of the polyalkylene glycol unsaturated monomer (a) and 60 to 3% by mass of the unsaturated monocarboxylic acid monomer (b) Are copolymerized.

Examples of the polycarboxylic acid polymer (B1) obtained by copolymerizing the polyalkyleneimine alkylene oxide adduct monomer include polyalkylene glycol unsaturated monomers (a) and unsaturated monocarboxylic acid single monomers. A copolymer obtained by copolymerizing the monomer component essentially comprising the body (b) and the polyalkyleneimine alkylene oxide adduct monomer (c) is preferred. More preferably, the polyalkylene glycol unsaturated monomer (a) 98 to 40% by mass, the unsaturated monocarboxylic acid monomer (b) 1 to 50% by mass, and the polyalkyleneimine alkylene oxide adduct monomer. (C) It is obtained by copolymerizing a monomer component essentially comprising 1 to 50% by mass.

Examples of the polycarboxylic acid copolymer (B2) having a polyalkylene glycol side chain essentially comprising an oxyalkylene group having 3 or more carbon atoms include “in the polyalkylene glycol unsaturated monomer (a), In particular, a monomer containing a polyalkylene glycol unsaturated monomer (a) "and an" unsaturated monocarboxylic acid monomer (b) ", which essentially contains an oxyalkylene group having 3 or more carbon atoms. Those obtained by copolymerizing the components are preferred. More preferably, a monomer component containing 1 to 99% by mass of the polyalkylene glycol unsaturated monomer (a) and 99 to 1% by mass of the unsaturated monocarboxylic acid monomer (b) is copolymerized. More preferably, the polyalkylene glycol unsaturated monomer (a) 40 to 97% by mass and the unsaturated monocarboxylic acid monomer (b) 60 to 3% by mass It is obtained by copolymerizing body components.

Examples of the polycarboxylic acid polymer (B3) other than the polymer (B1) and the polymer (B2) include, among the polyalkylene glycol unsaturated monomers (a), particularly from oxyethylene groups alone. The polyalkylene glycol unsaturated monomer (a) and the unsaturated monocarboxylic acid monomer (b), and the polyalkyleneimine alkylene oxide adduct monomer (c) Those obtained by copolymerizing monomer components not included are preferred. More preferably, a monomer component containing 1 to 99% by mass of the polyalkylene glycol unsaturated monomer (a) and 99 to 1% by mass of the unsaturated monocarboxylic acid monomer (b) is copolymerized. More preferably, the polyalkylene glycol unsaturated monomer (a) 40 to 97% by mass and the unsaturated monocarboxylic acid monomer (b) 60 to 3% by mass It is obtained by copolymerizing body components. Hereinafter, the polyalkylene glycol-based unsaturated monomer (a), the unsaturated monocarboxylic acid-based monomer (b), and the polyalkyleneimine alkylene oxide adduct monomer (c) are respectively represented as monomers. Also referred to as (a), monomer (b) and monomer (c).

In the polymer (B) and the polymer (B1), the monomers that form these polycarboxylic acid polymers may be used alone or in combination of two or more. . If the mass ratio of these monomers is out of the above range, the function of the repeating unit formed by each monomer cannot be exhibited effectively, and the effects of the present invention can be fully expressed. There is a risk that it will not be possible. In the monomer component forming the polycarboxylic acid polymer (B), the mass ratio of the monomers (a) and (b) is the sum of the masses of the monomers (a) and (b). In the monomer component forming the polycarboxylic acid polymer (B1), the mass ratio of the monomers (a), (b) and (c) is: , And the mass of the monomers (a), (b) and (c) is 100% by mass. In the present invention, as described later, other monomers other than the above-mentioned monomers can be used. However, when other monomers are used, the monomers (a) and (b) And the sum of (c) is preferably the main component in the monomer component.

In the monomer component forming the polymer (B1), the polyalkylene glycol unsaturated monomer (a) may be any one having a polymerizable unsaturated group and a polyalkylene glycol chain. The polyalkylene glycol unsaturated monomer (a) is preferably a compound represented by the general formula (1). More preferred are polyalkylene glycol ester monomers or unsaturated alcohol polyalkylene glycol adducts.

The polyalkylene glycol ester monomer may be any monomer having a structure in which an unsaturated group and a polyalkylene glycol chain are bonded via an ester bond. An unsaturated carboxylic acid polyalkylene glycol ester monomer may be used. Compounds are preferred, among which (alkoxy) polyalkylene glycol mono (meth) acrylates are preferred. 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, such as a vinyl alcohol alkylene oxide adduct or a (meth) allyl alcohol alkylene oxide addition. 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-buten-1-ol alkylene oxide adduct, 2-methyl-3-buten-1-ol alkylene oxide adduct are preferred. is there.

When two or more oxyalkylene groups represented by (R ⁴ O) in the above general formula (1) are present in the same unsaturated alcohol polyalkylene glycol adduct, the oxy represented by (R ⁴ O) The alkylene group may be added in any form such as random addition, block addition, and alternating addition.

The oxyalkylene group represented by the above (R ⁴ O) is formed of one or more alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide, isobutylene oxide, 1-butene oxide, and 2-butene oxide. It is a structure.
Among such alkylene oxide adducts, ethylene oxide, propylene oxide, and butylene oxide adducts are preferable. Further, those mainly composed of ethylene oxide are more preferable.

M which is the average added mole number of the oxyalkylene group represented by the above (R ⁴ O) is a number of 1 to 300. When m exceeds 300, the polymerizability of the monomer is lowered. The preferred range of m is 2 or more, and the average added mole number of oxyethylene groups in (R ⁴ O) m is preferably 2 or more. If m is less than 2 or the average added mole number of the oxyethylene group is less than 2, there is a possibility that sufficient hydrophilicity and steric hindrance to disperse cement particles may not be obtained. There is a possibility that fluidity cannot be obtained. In order to obtain excellent fluidity, the range of m is preferably 3 or more, and more preferably 280 or less. More preferably, it is 5 or more, More preferably, it is 10 or more, Most preferably, it is 20 or more. Further, it is more preferably 250 or less, particularly preferably 150 or less. Moreover, as an average addition mole number of an oxyethylene group, 3 or more are preferable and 280 or less are preferable. More preferably, it is 10 or more, More preferably, it is 20 or more. Further, it is more preferably 250 or less, further preferably 200 or less, and particularly preferably 150 or less. In order to obtain low-viscosity concrete, the range of m is preferably 3 or more, and more preferably 100 or less. More preferably, it is 4 or more and 50 or less, More preferably, it is 4 or more, and 30 or less, Especially preferably, it is 5 or more, and 25 or less. In addition, the said average addition mole number means the average value of the mole number of the said organic group added in 1 mol of monomers.

As the unsaturated alcohol polyalkylene glycol adduct represented by the general formula (1), two or more types of monomers having different average addition mole numbers m of oxyalkylene groups can be used in combination. As a suitable combination, for example, a combination of two types of monomers (a) having a difference in m of 10 or more (preferably a difference in m of 20 or more), or a difference in the average added mole number m of each is 10 or more. A combination of three or more types of monomers (a) (preferably a difference of m of 20 or more) is exemplified. The range of m to be combined is a combination of a monomer (a) having an average added mole number m in the range of 40 to 300 and a monomer (a) in the range of 1 to 40 (provided that the difference in m is 10 or more, preferably 20 or more, a combination of a monomer (a) having an average added mole number m in the range of 20 to 300 and a monomer (a) in the range of 1 to 20 (provided that the difference in m is 10 or more, preferably 20 or more).

When R ⁵ has more than 20 carbon atoms, the polycarboxylic acid polymer is too hydrophobic, so that it may not be possible to obtain good dispersibility. A preferred form of R ⁵ is a hydrocarbon group having 1 to 20 carbon atoms or hydrogen from the viewpoint of dispersibility. More preferably, it is a hydrocarbon group having 10 or less carbon atoms, more preferably 3 or less carbon atoms, and particularly preferably 2 or less carbon atoms. Of the hydrocarbon groups, a saturated alkyl group and an unsaturated alkyl group are preferred. These alkyl groups may be linear or branched. In addition, in order to achieve excellent material separation prevention performance and an appropriate amount of air entrained in the cement composition, it is preferably a hydrocarbon group having 5 or more carbon atoms. The hydrocarbon group is preferably 20 or less. More preferably, it is a C5-C10 hydrocarbon group. Of the hydrocarbon groups, a saturated alkyl group and an unsaturated alkyl group are preferred. These alkyl groups may be linear or branched.

Examples of the unsaturated alcohol polyalkylene glycol adduct include polyethylene glycol monovinyl ether, polyethylene glycol monoallyl ether, polyethylene glycol mono (2-methyl-2-propenyl) ether, polyethylene glycol mono (2-butenyl) ether, and 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-butenyl) 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, cyclohexyl Oxypolyethylene glycol mono (3-methyl-3-butenyl) ether, 1-octyloxypolyethylene glycol mono (3-methyl-3-butenyl) ether, nonylalkoxy polyethylene glycol mono (3-methyl-3-butenyl) ether, laurylalkoxy Polyethylene glycol mono (3-methyl-3-butenyl) ether, stearylalkoxy polyethylene glycol mono (3-methyl-3-butenyl) ether, phenoxypolyethylene Cole mono (3-methyl-3-butenyl) ether, naphthoxypolyethylene glycol mono (3-methyl-3-butenyl) ether, methoxypolyethylene glycol monoallyl ether, ethoxypolyethylene glycol monoallyl ether, phenoxypolyethylene glycol monoallyl ether, Methoxy polyethylene glycol mono (2-methyl-2-propenyl) ether, ethoxy polyethylene glycol mono (2-methyl-2-propenyl) ether, phenoxy polyethylene glycol mono (2-methyl-2-propenyl) ether, and the like are preferable.

The (alkoxy) polyalkylene glycol mono (meth) acrylic acid ester is preferably a compound represented by the following general formula (3).

In the general formula (3), R ⁸ represents a hydrogen atom or a methyl group. R ^a is the same or different and represents an alkylene group having 2 to 18 carbon atoms. R ⁹ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms. p represents the average addition mole number of the oxyalkylene group represented by R ^a O, and is a number of 2 to 300. The oxyalkylene group represented by R ^a O preferably has 2 to 4 carbon atoms. Moreover, it is preferable from the point of the productivity improvement of esterification with (meth) acrylic acid that the ethylene oxide part is added to the ester bond part with (meth) acrylic acid.

P which is the average addition mole number of the oxyalkylene group represented by the R ^a O is a number of 2 to 300. When p exceeds 300, the polymerizability of the monomer is lowered. The preferable range of p is 2 or more, and the average added mole number of the oxyethylene group in — (R ^a O) p— is preferably 2 or more. When p is less than 2 or the average number of added moles of oxyethylene groups is less than 2, there is a possibility that sufficient hydrophilicity and steric hindrance to disperse cement particles and the like may not be obtained. There is a possibility that fluidity cannot be obtained. In order to obtain excellent fluidity, the range of p is preferably 3 or more, and more preferably 280 or less. More preferably, it is 5 or more, More preferably, it is 10 or more, Most preferably, it is 20 or more. Further, it is more preferably 250 or less, further preferably 200 or less, and particularly preferably 150 or less. Moreover, as an average addition mole number of an oxyalkylene group, 5 or more are preferable and 250 or less are preferable. More preferably, it is 10 or more, More preferably, it is 20 or more. Further, it is more preferably 200 or less, and still more preferably 150 or less. In order to obtain concrete with low viscosity, the range of p is preferably 3 or more, and more preferably 100 or less. More preferably, it is 4 or more, 50 or less, More preferably, it is 4 or more, and 30 or less, Especially preferably, it is 5 or more, and 25 or less. In addition, the said average addition mole number means the average value of the mole number of the said organic group added in 1 mol of monomers.

As the (alkoxy) polyalkylene glycol mono (meth) acrylic acid ester represented by the general formula (3), it is possible to use a combination of two or more monomers having different average addition mole numbers p of oxyalkylene groups. it can. As a suitable combination, for example, a combination of two types of monomers (a) having a difference of p of 10 or more (preferably a difference of p of 20 or more), or a difference of each average added mole number p of 10 or more. A combination of three or more types of monomers (a) (preferably having a difference of p of 20 or more) is exemplified. The range of p to be combined is a combination of a monomer (a) having an average added mole number p in the range of 40 to 300 and a monomer (a) in the range of 2 to 40 (provided that the difference in p is 10 or more, preferably 20 or more), a combination of a monomer (a) having an average addition mole number p in the range of 20 to 300 and a monomer (a) in the range of 2 to 20 (provided that the difference in p is 10 or more, preferably 20 or more).

When R ⁹ has more than 30 carbon atoms, the polycarboxylic acid polymer becomes too hydrophobic, so that good dispersibility cannot be obtained. A preferred form of R ⁹ is a hydrocarbon group having 1 to 20 carbon atoms or hydrogen from the viewpoint of dispersibility. More preferably, it is a hydrocarbon group having 10 or less carbon atoms, more preferably 3 or less carbon atoms, and particularly preferably 2 or less carbon atoms. Of the hydrocarbon groups, a saturated alkyl group and an unsaturated alkyl group are preferred. These alkyl groups may be linear or branched. In addition, in order to achieve excellent material separation prevention performance and an appropriate amount of air entrained in the cement composition, it is preferably a hydrocarbon group having 5 or more carbon atoms. The hydrocarbon group is preferably 20 or less. More preferably, it is a C5-C10 hydrocarbon group. Of the hydrocarbon groups, a saturated alkyl group and an unsaturated alkyl group are preferred. These alkyl groups may be linear or branched.

Examples of the (alkoxy) polyalkylene glycol mono (meth) acrylate include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-pentanol, 2-pentanol, 3 -C 1-30 aliphatic alcohols such as pentanol, 1-hexanol, 2-hexanol, 3-hexanol, octanol, 2-ethyl-1-hexanol, nonyl alcohol, lauryl alcohol, cetyl alcohol, stearyl alcohol, C 3-30 alicyclic alcohols such as cyclohexanol, (meth) allyl alcohol, 3-buten-1-ol, 3-methyl-3-buten-1-ol, etc. Alkyl having 2 to 18 carbon atoms is added to any saturated alcohol Alkoxy polyalkylene glycols to N'okishido groups was 1 to 300 mols, particularly the alkoxy polyalkylene glycol is ethylene oxide mainly is suitably esterified products of (meth) acrylic acid.

As the esterified product, the following (alkoxy) polyethylene glycol (poly) (alkylene glycol having 2 to 4 carbon atoms) (meth) acrylic acid esters and the like are preferable.
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, ethoxypolyethylene glycol mono (meth) acrylate, ethoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, ethoxy {polyethylene glycol (poly) butylene glycol} 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.

Decanoxy polyethylene glycol mono (meth) acrylate, decananoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, decanoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, decanoxy {polyethylene glycol (poly) Propylene glycol (poly) butylene glycol} mono (meth) acrylate, undecanoxy polyethylene glycol mono (meth) acrylate, undecananoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, undecanoxy {polyethylene glycol (poly) butylene glycol } Mono (meth) acrylate, undecanoxy {polyethylene glycol (poly) propylene glycol (Poly) butylene glycol} mono (meth) acrylate, dodecanoxy polyethylene glycol mono (meth) acrylate, dodecananoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, dodecanoxy {polyethylene glycol (poly) butylene glycol} Mono (meth) acrylate, dodecanoxy {polyethylene glycol (poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate.

Tridecanoxy polyethylene glycol mono (meth) acrylate, tridecananoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, tridecanoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, tridecanoxy {polyethylene glycol (poly) Propylene glycol (poly) butylene glycol} mono (meth) acrylate, tetradecanoxy polyethylene glycol mono (meth) acrylate, tetradecananoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, tetradecanoxy {polyethylene glycol ( Poly) butylene glycol} mono (meth) acrylate, tetradecanoxy {polyethylene glycol Poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate, pentadecanoxy polyethylene glycol mono (meth) acrylate, pentadecananoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, pentadecanoxy {polyethylene Glycol (poly) butylene glycol} mono (meth) acrylate, pentadecanoxy {polyethylene glycol (poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate. Hexadecanoxy polyethylene glycol mono (meth) acrylate, hexadecananoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, hexadecanoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, hexadecanoxy {polyethylene Glycol (poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate, heptadecanoxy polyethylene glycol mono (meth) acrylate, heptadecanoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, heptadecanoxy {Polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, heptadecanoxy {polyethylene group Cole (poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate, octadecanoxy polyethylene glycol mono (meth) acrylate, octadecananoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, octadecanoxy {Polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, octadecanoxy {polyethylene glycol (poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate.

Nonadecanoxy polyethylene glycol mono (meth) acrylate, nonadecanoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, nonadecanoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, nonadecanoxy {polyethylene glycol (poly) ) Propylene glycol (poly) butylene glycol} mono (meth) acrylate, cyclopentoxypolyethylene glycol mono (meth) acrylate, cyclopentoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, cyclopentoxy {polyethylene glycol (Poly) butylene glycol} mono (meth) acrylate, cyclopentoxy {polyethylene glycol ( B) propylene glycol (poly) butylene glycol} mono (meth) acrylate, cyclohexoxypolyethylene glycol mono (meth) acrylate, cyclohexoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, cyclohexoxy {polyethylene glycol (poly) ) Butylene glycol} mono (meth) acrylate, cyclohexoxy {polyethylene glycol (poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate.

Examples of the (alkoxy) polyalkylene glycol mono (meth) acrylic acid ester include phenoxy polyethylene glycol mono (meth) acrylate, phenoxy {polyethylene glycol (poly) propylene, in addition to the compound represented by the general formula (3). Glycol} mono (meth) acrylate, phenoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, phenoxy {polyethylene glycol (poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate, (meth) allyloxy Polyethylene glycol mono (meth) acrylate, (meth) allyloxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, (meth) allyloxy { Triethylene glycol (poly) butylene glycol} mono (meth) acrylate, (meth) allyloxy {polyethylene glycol (poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate are preferred.

Examples of the polyalkylene glycol ester monomer include (alkoxy) polyalkylene glycol mono (meth) acrylic acid ester, (alkoxy) polyalkylene glycol monomaleic acid ester, and (alkoxy) polyalkylene glycol dimaleic acid. Esters are preferred. As such a monomer, the following are suitable. Half of an alkyl polyalkylene glycol obtained by adding 1 to 300 moles of oxyalkylene having 2 to 4 carbon atoms to an alcohol having 1 to 22 carbon atoms or an amine having 1 to 22 carbon atoms and the above unsaturated dicarboxylic acid monomer Esters, diesters; half esters and diesters of the above unsaturated dicarboxylic acid monomers and polyalkylene glycols having an average addition mole number of 2 to 300 carbon atoms of glycols having 2 to 4 carbon atoms; triethylene glycol di (meth) acrylates, ( (Poly) ethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, (poly) ethylene glycol (poly) propylene glycol di (meth) acrylate and other (poly) alkylene glycol di (meth) acrylates; triethylene glycol Zimarate, polyethylene (Poly) alkylene glycol dimaleate such as glycol dimaleate.

In the monomer component forming the polymer (B), the unsaturated monocarboxylic acid monomer (b) is a monomer having a polymerizable unsaturated group and a group capable of forming a carbanion. An unsaturated monocarboxylic acid monomer or the like is preferable. The unsaturated monocarboxylic acid-based monomer may be any monomer having one unsaturated group and one group capable of forming a carbanion in the molecule. It is a compound represented by 2).

R ⁶ is preferably a hydrogen atom. R ⁷ is preferably a hydrogen atom. As the metal atom in M ¹ of the general formula (2), a monovalent metal atom such as an alkali metal atom such as lithium, sodium or potassium; a divalent metal atom such as an alkaline earth metal atom such as calcium or magnesium; A trivalent metal atom such as aluminum or iron is preferred. Moreover, as an organic amine group, alkanolamine groups, such as an ethanolamine group, a diethanolamine group, and a triethanolamine group, and a triethylamine group are suitable. Further, it may be an ammonium group. As such an unsaturated monocarboxylic acid monomer, acrylic acid, methacrylic acid, crotonic acid and the like; monovalent metal salts, divalent metal salts, ammonium salts, and organic amine salts thereof are suitable. Among these, methacrylic acid; its monovalent metal salt, divalent metal salt, ammonium salt, and organic amine salt are preferably used from the viewpoint of improving cement dispersibility, and unsaturated monocarboxylic acid monomer (b ).

In the monomer component forming the polymer (B1), the polyalkyleneimine alkylene oxide adduct monomer (c) may be a polyalkyleneimine having an unsaturated group and an oxyalkylene group. As a method for producing such a monomer (c), for example, a compound in which an alkylene oxide is added to the nitrogen atom of the amino group or imino group of the polyalkyleneimine described above (has a polymerizable unsaturated double bond). The polyalkyleneimine alkylene oxide adduct) is preferably reacted with an unsaturated compound having a functional group that reacts with the hydroxyl group, amino group or imino group of the compound. In the case of obtaining the above-mentioned polyalkyleneimine alkylene oxide adduct monomer (c), as a method for introducing an unsaturated group into a compound obtained by adding an alkylene oxide to a polyalkyleneimine, a compound obtained by adding an alkylene oxide to a polyalkyleneimine A method in which an unsaturated group is introduced by transesterifying a hydroxyl group having an unsaturated compound such as (meth) acrylic acid or (meth) acrylic acid alkyl ester, an amino group having a compound in which an alkylene oxide is added to a polyalkyleneimine. A method of introducing an unsaturated group by amidation with an unsaturated compound such as (meth) acrylic acid or (meth) acrylic acid alkyl ester, a glycidyl (meth) acrylate having a hydroxyl group of a compound obtained by adding an alkylene oxide to a polyalkyleneimine Ya (meth) allyl glycidyl A Method by reacting an epoxy compound such as Le introducing an unsaturated group are preferred.
The compound obtained by adding an alkylene oxide to the polyalkyleneimine and the preferred form thereof are the same as those having no polymerizable unsaturated double bond in the polyalkyleneimine alkylene oxide adduct (c) described above.

Examples of the unsaturated compound include unsaturated monocarboxylic acids such as (meth) acrylic acid; unsaturated carboxylic acid anhydrides such as (meth) acrylic anhydride; unsaturated carboxylic acid halides such as (meth) acrylic chloride. Unsaturated carboxylic acid esters such as (meth) acrylic acid alkyl esters having 1 to 30 carbon atoms, maleic acid monoesters having 1 to 30 carbon atoms, and maleic acid diesters having 1 to 30 carbon atoms; glycidyl (meth) acrylates; Epoxy compounds such as (meth) allyl glycidyl ether are suitable, and one or more of these can be used.

As an example of a reaction formula for obtaining the above polyalkyleneimine alkylene oxide adduct monomer (c), after synthesizing polyethyleneimine with an initiator and ethyleneimine, ethyleneoxide is added to a nitrogen atom having an active hydrogen atom of polyethyleneimine. It is preferable to add to a polyethyleneimine ethylene oxide adduct and then to perform a transesterification reaction with methacrylic acid. In addition, after synthesizing polyethyleneimine, a method of adding polyethyleneimine to a nitrogen atom having an active hydrogen atom of polyethyleneimine to give a polyethyleneimine ethyleneoxide adduct, and then reacting with glycidyl methacrylate, polyalkyleneiminealkyleneoxide An adduct monomer (c) can be obtained.

Further, a monomer component for forming a polycarboxylic acid polymer (B1) obtained by copolymerizing a polycarboxylic acid polymer (B) or a polyalkyleneimine alkylene oxide adduct monomer is further required. Depending on the above, other monomers (d) other than the monomers (a), (b) and (c) may be included. As the other monomer (d), the following are suitable. These may be used alone or in combination of two or more. Styrenes such as styrene, bromostyrene, chlorostyrene, and methylstyrene; dienes such as 1,3-butadiene, isoprene, and isobutylene; methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, (Meth) acrylic acid esters such as pentyl (meth) acrylate, hexyl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate; α-olefins such as hexene, heptene, decene; methyl Alkyl vinyl ethers such as vinyl ether, ethyl vinyl ether and butyl vinyl ether; vinyl esters such as vinyl acetate; allyl esters such as allyl acetate. Bifunctional (meth) acrylates such as hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane di (meth) acrylate; vinyl sulfonate, (meth) allyl sulfonate, 2- (meth) acrylate Roxyethyl sulfonate, 3- (meth) acryloxypropyl sulfonate, 3- (meth) acryloxy-2-hydroxypropyl sulfonate, 3- (meth) acryloxy-2-hydroxypropylsulfophenyl ether, 3- (meth) acryloxy-2 -Hydroxypropyloxysulfobenzoate, 4- (meth) acryloxybutylsulfonate, (meth) acrylamidomethylsulfonic acid, (meth) acrylamidoethylsulfonic acid, 2-methylpropanesulfonic acid ( Data) acrylamide, unsaturated sulfonic acids such as styrenesulfonic acid, and their monovalent metal salts, divalent metal salts, ammonium salts and organic amine salts.

Unsaturated amides such as (meth) acrylamide, (meth) acrylic alkylamide, N-methylol (meth) acrylamide, N, N-dimethyl (meth) acrylamide; allyls such as allyl alcohol; dimethylaminoethyl (meth) acrylate Unsaturated amino compounds such as methoxypolyethylene glycol monovinyl ether, polyethylene glycol monovinyl ether, methoxypolyethylene glycol mono (meth) allyl ether, and vinyl ethers or allyl ethers such as polyethylene glycol mono (meth) allyl ether.

(Meth) acrylate compounds such as hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, butoxyethylethyl (meth) acrylate, methoxypropyl (meth) acrylate, etc. .

For the sulfonic acid compound (C), lignin sulfonic acid; lignin sulfonate; naphthalene sulfonic acid; naphthalene sulfonate; naphthalene sulfonic acid formalin condensate; melamine sulfonic acid; melamine sulfonic acid salt; melamine sulfonic acid formalin condensate Polystyrene sulfonate; etc. are preferred. These may be used alone or in combination of two or more. The other monomer (d) does not include unsaturated dicarboxylic acid monomers such as maleic acid.

Next, the copolymerization method of the monomer component in the production method of the polycarboxylic acid polymer (B) will be described below.
As said copolymerization method, it can carry out by normal polymerization methods, such as solution polymerization and block polymerization, using a monomer component and a polymerization initiator, for example. As the polymerization initiator, those usually used can be used. Persulfates such as ammonium persulfate, sodium persulfate and potassium persulfate; hydrogen peroxide; azobis-2-methylpropionamidine hydrochloride, azoisobutyro Preferred are azo compounds such as nitriles; peroxides such as benzoyl peroxide, lauroyl peroxide, cumene hydroperoxide. In addition, as a promoter, reducing agents such as sodium bisulfite, sodium sulfite, molle salt, sodium pyrobisulfite, formaldehyde sodium sulfoxylate, ascorbic acid; and amine compounds such as ethylenediamine, sodium ethylenediaminetetraacetate, glycine, etc. You can also. These polymerization initiators and accelerators may be used alone or in combination of two or more.

In the above copolymerization method, a chain transfer agent can be used as necessary, and one or more commonly used ones can be used. As such a chain transfer agent, a hydrophilic chain transfer agent is preferably used, but a hydrophobic chain transfer agent can also be used as necessary. In the copolymerization method, when the monomer component includes one or more of a monomer having an oxyalkylene group, that is, a polyalkylene glycol unsaturated monomer (a), a hydrophobic chain A transfer agent can also be used. As the hydrophilic chain transfer agent, commonly used ones can be used, such as mercaptoethanol, thioglycerol, thioglycolic acid, mercaptopropionic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thiomalic acid, 2 -Thiol chain transfer agents such as mercaptoethanesulfonic acid; primary alcohols such as 2-aminopropan-1-ol; secondary alcohols such as isopropanol; phosphorous acid, hypophosphorous acid and salts thereof (hypophosphorous acid) Sodium, potassium hypophosphite, etc.), sulfurous acid, hydrogen sulfite, dithionite, metabisulfite and its salts (sodium sulfite, sodium bisulfite, sodium dithionite, sodium metabisulfite, potassium sulfite, hydrogen sulfite) Potassium, potassium dithionite, potassium metabisulfite Lower oxides and salts thereof are preferred in).

The hydrophilic chain transfer agent may be used in combination with one or two hydrophobic chain transfer agents as required. The hydrophobic chain transfer agent is preferably a thiol compound having a hydrocarbon group having 3 or more carbon atoms or a compound having a solubility in water of 25 ° C. of 10% or less. The chain transfer agent, butanethiol, octane described above Thiol, decanethiol, dodecanethiol, hexadecanethiol, octadecanethiol, cyclohexyl mercaptan, thiophenol, octyl thioglycolate, octyl 2-mercaptopropionate, octyl 3-mercaptopropionate, 2-ethylhexyl ester mercaptopropionate, octanoic acid 2 -Thiol chain transfer agents such as mercaptoethyl ester, 1,8-dimercapto-3,6-dioxaoctane, decanetrithiol, dodecyl mercaptan; carbon tetrachloride, carbon tetrabromide, methylene chloride, bromoform, Halides mode trichloroethane; alpha-methylstyrene dimer, alpha-terpinene, .gamma.-terpinene, dipentene, unsaturated hydrocarbon compounds such as terpinolene are preferable. These may be used alone or in combination of two or more. Among these, it is preferable to include a thiol chain transfer agent having a hydrocarbon group having 3 or more carbon atoms.

As a method for adding the chain transfer agent to the reaction vessel, a continuous charging method such as dropping or divided charging can be applied. In addition, the chain transfer agent may be introduced alone into the reaction vessel, or may be previously confused with a monomer having an oxyalkylene group constituting the monomer component, a solvent, or the like.

The copolymerization method can be carried out either batchwise or continuously. Moreover, as a solvent used as needed in the case of copolymerization, what is usually used can be used, water; alcohols, such as methyl alcohol, ethyl alcohol, isopropyl alcohol; benzene, toluene, xylene, cyclohexane, n -Aromatic or aliphatic hydrocarbons such as heptane; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone are preferred. These may be used alone or in combination of two or more. Among these, from the solubility point of the monomer component and the resulting polycarboxylic acid polymer, one or more solvents selected from the group consisting of water and lower alcohols having 1 to 4 carbon atoms are used. It is preferable to use it.

In the above copolymerization method, monomer components, polymerization initiators, etc. can be added to the reaction vessel by charging all of the monomer components into the reaction vessel and adding the polymerization initiator into the reaction vessel. A method for carrying out polymerization; a method for carrying out copolymerization by charging a part of a monomer component into a reaction vessel and adding a polymerization initiator and the remaining monomer component into the reaction vessel; a polymerization solvent in the reaction vessel A method of charging, adding the monomer components and the total amount of the polymerization initiator, and the like are preferable. Among these methods, the molecular weight distribution of the obtained polymer can be narrowed (sharpened), and the cement dispersibility, which is an effect of improving the fluidity of the cement composition and the like, can be improved. It is preferable to carry out the copolymerization by a method in which the agent and the monomer component are successively dropped into the reaction vessel. In addition, since the storage stability of the polymer obtained by improving the copolymerization of the monomer component is further improved, the concentration of water in the reaction vessel during the copolymerization is maintained at 50% or less for the copolymerization. It is preferable to carry out the reaction. More preferably, it is 40% or less, More preferably, it is 30% or less.

In the above copolymerization method, the copolymerization conditions such as the copolymerization temperature are appropriately determined depending on the copolymerization method used, the solvent, the polymerization initiator, and the chain transfer agent, but the copolymerization temperature is usually 0 ° C. or higher. It is preferable that it is 150 degrees C or less. More preferably, it is 40 degreeC or more, More preferably, it is 50 degreeC or more, Especially preferably, it is 60 degreeC or more. Further, it is more preferably 120 ° C. or lower, further preferably 100 ° C. or lower, and particularly preferably 85 ° C. or lower.

The polymer obtained by the above copolymerization method is used as it is as a main component of the cement additive, but may be further neutralized with an alkaline substance if necessary. As the alkaline substance, it is preferable to use inorganic salts such as hydroxides, chlorides and carbonates of monovalent metals and divalent metals; ammonia; organic amines.

In the said copolymerization method, it is preferable to copolymerize a monomer component by making the neutralization rate of the said unsaturated monocarboxylic-acid type monomer (b) 0-60 mol%. The neutralization rate of the unsaturated monocarboxylic acid monomer (b) is the amount of unsaturation forming a salt when the total number of moles of the unsaturated monocarboxylic acid monomer (b) is 100 mol%. It is represented by mol% of the monocarboxylic acid monomer (b). When the neutralization rate of the unsaturated monocarboxylic acid monomer (b) exceeds 60 mol%, the polymerization rate in the copolymerization process does not increase, the molecular weight of the resulting polymer decreases, or the production efficiency decreases. There is a risk. More preferably, it is 50 mol% or less, More preferably, it is 40 mol% or less, More preferably, it is 30 mol% or less, Especially preferably, it is 20 mol% or less, Most preferably, it is 10 mol% or less.

As a method for carrying out the copolymerization at a neutralization rate of the unsaturated monocarboxylic acid monomer (b) of 0 to 60 mol%, the unsaturated monocarboxylic acid monomer (b), which is all in acid form, In all unsaturated monocarboxylic acid monomers (b), a method in which M ¹ in the above general formula (2) is a hydrogen atom is subjected to copolymerization without neutralization; By subjecting the carboxylic acid monomer (b) to a copolymerization with a neutralization rate of 0 to 60 mol% when neutralizing into a salt form such as sodium salt or ammonium salt using an alkaline substance The method of performing is preferred.

As described above, the polycarboxylic acid polymer (B1) obtained by copolymerizing the polycarboxylic acid polymer (B) and the polyalkyleneimine alkylene oxide adduct monomer in the present invention contains monomer components as described above. The molecular weight of such a polymer is preferably 500 or more in terms of polyethylene glycol equivalent weight average molecular weight (Mw) by gel permeation chromatography (hereinafter referred to as “GPC”). Moreover, it is preferable that it is 500,000 or less. If it is less than 500, the water-reducing performance of these polycarboxylic acid polymers may be lowered, and if it exceeds 500,000, the water-reducing performance and slump loss preventing ability of the polycarboxylic acid polymers may be lowered. More preferably, it is 5000 or more, and most preferably 8000 or more. Further, it is more preferably 300,000 or less, and most preferably 100,000 or less.

In the present specification, the weight average molecular weight of the polymer (B) is a value measured under the following GPC measurement conditions.
(GPC molecular weight measurement conditions)
Column used: TSK guard column SWXL + TSKge1 G4 manufactured by Tosoh Corporation
000SWXL + G3000SWXL + G2000SWXL
Eluent: An eluent solution prepared by dissolving 115.6 g of sodium acetate trihydrate in a mixed solvent of 10999 g of water and 6001 g of acetonitrile and adjusting the pH to 6.0 with acetic acid is used.
Implanted amount: 100 μL of 0.5% eluent solution
Eluent flow rate: 0.8 mL / min
Column temperature: 40 ° C
Standard substance: polyethylene glycol, top peak molecular weight (Mp) 272500, 219300, 85000, 46000, 24000, 12600, 4250, 7100, 1470.
Calibration curve order: Tertiary detector: 410 manufactured by Waters, Japan 410 Differential refraction detector analysis software: MILRENNIUM Ver. Manufactured by Waters, Japan 5.00

The cement admixture of the present invention comprises the adduct (A) as an essential component, the adduct (A) and the polycarboxylic acid polymer (B) as essential components, or the adduct (A) and a sulfone. An acid compound (C) is an essential component, or an adduct (A), a polycarboxylic acid polymer (B), and a sulfonic acid compound (C) are essential components. Such a cement admixture means an agent that can be mixed with a cement composition or the like, that is, an agent comprising a cement additive or the like. A cement admixture containing the essential component as a main component is one of the preferred embodiments of the present invention.
The adduct (A) and the polycarboxylic acid polymer (B) are suitable as the main component of the cement additive, and the cement admixture of the present invention can also be constituted by these. Such cement additives are described below. The cement additive can be used in addition to a cement composition such as cement paste, mortar, and concrete. It can also be used for ultra high strength concrete. As the cement composition, those usually used including cement, water, fine aggregate, coarse aggregate and the like are suitable. Moreover, what added fine powders, such as a fly ash, blast furnace slag, a silica fume, and a limestone, may be used. Ultra-high-strength concrete is generally called as such in the field of cement composition, that is, the cured product is equivalent to the conventional one even if the water / cement ratio is smaller than that of conventional concrete. Or concrete having a higher strength, for example, the water / cement ratio is 25% by mass or less, further 20% by mass or less, particularly 18% by mass or less, particularly 14% by mass or less, especially about 12% by mass. However, it becomes a concrete having workability that does not hinder normal use, and the cured product thereof is 60 N / mm ² or more, further 80 N / mm ² or more, further 100 N / mm ² or more, particularly 120 N / mm ² or more. , in particular 160 N / mm ² or more, and particularly will exhibit 200 N / mm ² or more compression strength.

As the cement, portland cement such as normal, early strength, super early strength, moderate heat, white, etc .; mixed portland cement such as alumina cement, fly ash cement, blast furnace cement, silica cement and the like are suitable. The amount and unit water per concrete 1m3 of the cement, for example, to produce a concrete high durability and high strength, the unit water amount 100~185kg / ^{m 3,} water / cement ratio = 10% to 70% It is preferable that More preferably, the unit water amount is 120 to 175 kg / m ³ and the water / cement ratio is 20 to 65%.

As the addition amount of the cement additive to the cement composition, the adduct (A), the polycarboxylic acid polymer (B), and the sulfonic acid compound (C) are used in a total amount of 100 mass% of the cement mass. Therefore, it is preferable to be 0.01% by mass or more, and it is preferable to be 10% by mass or less. If it is less than 0.01% by mass, the performance may be insufficient, and if it exceeds 10% by mass, the economical efficiency will be inferior. More preferably, it is 0.05 mass% or more, and is 8 mass% or less, More preferably, it is 0.1 mass% or more, and is 5 mass% or less. In addition, the said mass% is a value of solid content conversion.
The cement additive can be used in combination with a commonly used cement dispersant. The following are preferable as the cement dispersant.

Polyol derivatives; aminosulfonic acid series such as aminoarylsulfonic acid-phenol-formaldehyde condensate as described in JP-A-1-113419; polyalkylene as component (a) as described in JP-A-7-267705 Copolymer of glycol mono (meth) acrylic acid ester compound and (meth) acrylic acid compound and / or salt thereof, and (b) component, polyalkylene glycol mono (meth) allyl ether compound and maleic anhydride A copolymer with an acid and / or a hydrolyzate thereof and / or a salt thereof, as a component (c), a polyalkylene glycol mono (meth) allyl ether compound, and a maleic ester of a polyalkylene glycol compound; A cement dispersant containing a copolymer and / or a salt thereof; As described in No. 2508113, the component A is a copolymer of a poly (alkylene glycol ester of (meth) acrylic acid and (meth) acrylic acid (salt), and the component B is a specific polyethylene glycol polypropylene glycol compound. Concrete admixture comprising a specific surfactant as component C; as described in JP-A-62-216950, polyethylene (propylene) glycol ester of (meth) acrylic acid or polyethylene (propylene) glycol mono (meth) A copolymer comprising allyl ether, (meth) allylsulfonic acid (salt), and (meth) acrylic acid (salt).

A copolymer comprising polyethylene (propylene) glycol ester of (meth) acrylic acid, (meth) allylsulfonic acid (salt), and (meth) acrylic acid (salt) as described in JP-A-1-226757; As described in JP-B-5-36377, (meth) acrylic acid polyethylene (propylene) glycol ester, (meth) allylsulfonic acid (salt) or p- (meth) allyloxybenzenesulfonic acid (salt), and Copolymer comprising (meth) acrylic acid (salt); copolymer of polyethylene glycol mono (meth) allyl ether and maleic acid (salt) as described in JP-A-4-149056; JP-A-5-170501 (Meth) acrylic acid polyethylene glycol ester, (meth) allylsulfonic acid ( ), (Meth) acrylic acid (salt), alkanediol mono (meth) acrylate, polyalkylene glycol mono (meth) acrylate, and α, β-unsaturated monomer having an amide group in the molecule Polymerization; as described in JP-A-6-191918, polyethylene glycol mono (meth) allyl ether, polyethylene glycol mono (meth) acrylate, (meth) acrylic acid alkyl ester, (meth) acrylic acid (salt), and ( Copolymer comprising meth) allylsulfonic acid (salt) or p- (meth) allyloxybenzenesulfonic acid (salt); alkoxypolyalkylene glycol monoallyl ether and maleic anhydride as described in JP-A-5-43288 Copolymer or its hydrolyzate or its salt; Polyethylene glycol monoallyl ether as described in 58-38380 JP, maleic acid, and copolymers composed of these monomers copolymerizable with monomer, or a salt thereof, or an ester thereof.

As described in JP-B-59-18338, polyalkylene glycol mono (meth) acrylic acid ester monomer, (meth) acrylic acid monomer, and a monomer copolymerizable with these monomers A copolymer comprising a polymer; a copolymer comprising a (meth) acrylic acid ester having a sulfonic acid group and a monomer copolymerizable therewith as described in JP-A-62-1119147, or Salt thereof; as described in JP-A-6-271347, an esterification reaction product of a copolymer of an alkoxy polyalkylene glycol monoallyl ether and maleic anhydride and a polyoxyalkylene derivative having an alkenyl group at the terminal; Copolymer of alkoxypolyalkylene glycol monoallyl ether and maleic anhydride as described in Kaihei 6-298555 , Esterification reaction product with a polyoxyalkylene derivative having a hydroxyl group at the terminal; as described in JP-A-62-68806, a specific unsaturated alcohol such as 3-methyl-3-buten-1-ol, ethylene oxide, etc. An alkenyl ether monomer, an unsaturated carboxylic acid monomer, a copolymer composed of a monomer copolymerizable with these monomers, or a polycarboxylic acid such as a salt thereof ( salt). These cement dispersants may be used alone or in combination of two or more.

When the cement dispersant is used in combination, it is not uniquely determined depending on the type of cement dispersant to be used, blending, test conditions, etc., but the proportion of the blending mass of the cement additive and the cement dispersant Is preferably 5 to 95:95 to 5. More preferably, it is 10-90: 90-10. The cement additive can also be used in combination with other cement additives. Examples of other cement additives include commonly used cement additives (materials) as shown below.

(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, Pakiman, Polysaccharides produced by microbial fermentation such as loglucan, laminaran, etc .; polyacrylamide; polyvinyl alcohol; starch; starch phosphate ester; sodium alginate; gelatin; copolymer of acrylic acid having an amino group in the molecule and its quaternary compound etc.
(2) Polymer emulsion: Copolymers of various vinyl monomers such as alkyl (meth) acrylate.
(3) retarder: oxycarboxylic such as gluconic acid, glucoheptonic acid, arabonic acid, malic acid or citric acid, and inorganic salts or organic salts thereof such as sodium, potassium, calcium, magnesium, ammonium, triethanolamine, etc. Acids and salts thereof; monosaccharides such as glucose, fructose, galactose, saccharose, xylose, apiose, ribose and isomerized sugar; oligosaccharides such as disaccharides and trisaccharides; oligosaccharides such as dextrin; Sugars, sugars such as molasses containing them; sugar alcohols such as sorbitol; magnesium silicate; phosphoric acid and its salts or boric acid esters; aminocarboxylic acids and their salts; alkali-soluble proteins; humic acids; Phenol; polyhydric alcohol such as glycerine; aminotri ( Tylene phosphonic acid), 1-hydroxyethylidene-1,1-diphosphonic acid, ethylenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta (methylenephosphonic acid) and their alkali metal salts, alkaline earth metal salts and other phosphonic acids and their derivatives etc.
(4) Early strengthening agents / accelerators: soluble calcium salts such as calcium chloride, calcium nitrite, calcium nitrate, calcium bromide and calcium iodide; chlorides such as iron chloride and magnesium chloride; sulfates; potassium hydroxide; Sodium hydroxide; carbonate; thiosulfate; formate such as formic acid and calcium formate; 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, alkylene oxide adducts thereof and the like.
(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 oxyethyleneoxypropylene adducts to higher alcohols having 12 to 14 carbon atoms; (poly) oxyalkylenes such as polyoxypropylene phenyl ether and polyoxyethylene nonylphenyl ether (Alkyl) aryl ethers; 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 2,5-dimethyl-3-hexyne-2,5-diol, 3-methyl-1- Spotted Acetylene ethers obtained by addition polymerization of alkylene oxide to acetylene alcohol such as -3-ol; (poly) oxyalkylene fatty acid esters such as diethylene glycol oleate, diethylene glycol laurate, ethylene glycol distearate; polyoxyethylene sorbitan (Poly) oxyalkylene sorbitan fatty acid esters such as monolaurate and polyoxyethylene sorbitan trioleate; (poly) oxyalkylene alkyl (aryl) such as sodium polyoxypropylene methyl ether sulfate and sodium polyoxyethylene dodecylphenol ether sulfate ) Ether sulfate esters; (Poly) oxy such as (poly) oxyethylene stearyl phosphate Ruki alkylene alkyl phosphate 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, alkenylsulfosuccinic 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, fats and oils, 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 commonly used cement additives (materials) include cement wetting agents, thickeners, separation reducing agents, flocculants, drying shrinkage reducing agents, strength enhancers, self-leveling agents, coloring agents, fungicides, Examples include blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica fume, silica powder, and gypsum. These cement additives (materials) may be used alone or in combination of two or more.

The above cement additive may be used in combination with the above-described commonly used cement dispersant and cement additive (material), as well as those that improve the dispersibility, foam suppression and the like of the cement composition.
As a method for adding the cement additive and the cement dispersant to the cement composition, it is preferable to mix these cement additives and the cement dispersant into a cement admixture so as to be easily mixed into the cement composition. .

One of the preferred embodiments of the present invention is that the alkylene oxide adduct obtained by adding an oxyalkylene group to the compound having 3 or more active hydrogens is a polyhydric alcohol alkylene oxide adduct.

The polyhydric alcohol alkylene oxide adduct (also referred to as polyhydric alcohol alkylene oxide adduct (A ′) or adduct (A ′)) will be described below. Note that (A ′) in the adduct (A ′) is simply a symbol given to distinguish it from the superordinate concept. Hereinafter, among the descriptions regarding the adduct (A ′), the description regarding the content of the carboxyl group (including the salt form) does not depend on whether the adduct (X) is a polyhydric alcohol alkylene oxide adduct. And it can apply similarly to the said adduct (X) which is a high-order concept.

The adduct (A ′) has a group formed by one oxyalkylene group or a group formed by adding two or more oxyalkylene groups (polyalkylene glycol chain). In the group formed by adding two or more oxyalkylene groups, the type of the oxyalkylene group forming the group may be only one type or two or more types. When formed by two or more oxyalkylene groups, the addition form of the two or more oxyalkylene groups may be any of random addition, block addition, and alternate addition. In addition, when two or more groups formed with the said oxyalkylene group exist in one molecule, these may be the same and may differ.

Examples of the oxyalkylene group include ethylene oxide (EO), propylene oxide (PO), isobutylene oxide, 1-butene oxide, 2-butene oxide, trimethylethylene oxide, tetramethylene oxide, tetramethylethylene oxide, butadiene monooxide, and octylene. Examples include groups derived from compounds such as oxide, styrene oxide, and 1,1-diphenylethylene oxide.

The group formed by the oxyalkylene group is preferably mainly composed of an oxyethylene group (—O—CH ₂ —CH ₂ —). In this case, “mainly composed of oxyalkylene groups” means that when two or more oxyalkylene groups are present in the monomer, the oxyalkylene groups occupy most of the total number of oxyalkylene groups present. It means that. Thereby, the hydrophilicity of the cement admixture is further improved, and the dispersibility can be more fully exhibited. More preferably, both an oxypropylene group and an oxyethylene group are essential. More preferably, as described later, a so-called PQP type (P: This is a form having a block copolymer structure of (oxyethylene group, Q: oxypropylene group).

The polyhydric alcohol constituting the polyhydric alcohol residue in the polyhydric alcohol alkylene oxide adduct means a compound having an average of 3 or more hydroxyl groups per molecule, and its specific form is not particularly limited. . The polyhydric alcohol is preferably a compound composed of three atoms of carbon, hydrogen, and oxygen.
The average value of the number of hydroxyl groups in one molecule of polyhydric alcohol is not particularly limited, but is preferably 3 to 300, more preferably 4 to 100, still more preferably 5 to 50, Preferably 6 to 25. When the average value of the hydroxyl groups of one molecule of the polyhydric alcohol is within the above range, the polyhydric alcohol alkylene oxide adduct can sufficiently function as a monomer.

Preferable specific examples of the polyhydric alcohol include, for example, polyglycidol, glycerin, polyglycerin, trimethylolethane, trimethylolpropane, 1,3,5-pentatriol, erythritol, pentaerythritol, dipentaerythritol, sorbitol, sorbitan Sorbitol glycerin condensate, adonitol, arabitol, xylitol, mannitol. Also, sugars of hexoses such as glucose, fructose, mannose, indose, sorbose, growth, talose, tagatose, galactose, allose, psicose, altrose; saccharides of pentoses such as arabinose, ribulose, ribose, xylose, xylulose, lyxose Sugars of tetroses such as threose, erythrulose, erythrose; other sugars such as rhamnose, cellobiose, maltose, isomaltose, trehalose, sucrose, raffinose, gentianose, merezitose; these sugar alcohols, sugar acids (sugars; glucose, Sugar alcohol; glucite, sugar acid; gluconic acid) can also be preferably used. Furthermore, derivatives of these compounds such as partially etherified products and partially esterified products can also be preferably used. One of these polyhydric alcohols may be used alone, or two or more thereof may be used in combination. Among the polyhydric alcohols, in the present invention, it is more preferable to use a polyhydric alcohol (for example, saccharide) having a structure in which a hydroxyl group is bonded to each of two adjacent carbon atoms. Is particularly preferred, and sorbitol is most preferred.
From the viewpoint of not inhibiting the performance as a cement dispersant, the content of carboxyl groups (including salt forms) contained in the polyhydric alcohol alkylene oxide adduct is 1 mol of oxyalkylene groups contained in the adduct. It is preferable that it is 0.02 mol or less. More preferably, it is 0.01 mol or less, still more preferably 0.005 mol or less, particularly preferably not containing a carboxyl group, and most preferably 0 mol.

In the above oxyalkylene group, when “mainly composed of oxyethylene groups” is represented by mol% of oxyethylene groups in 100 mol% of all oxyalkylene groups, it is preferably 50 to 100 mol%. If the content of the oxyethylene group is less than 50 mol%, the hydrophilicity of the group formed from the oxyalkylene group may be lowered. 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 addition mole number of the oxyalkylene group in the polyhydric alcohol alkylene oxide adduct is preferably more than 0 and 500 moles or less with respect to 1 mole of the hydroxyl group (—OH group). If the number of added moles exceeds 500, the polymerizability of the monomer may be reduced. The lower limit value of the average number of added moles is more preferably 1 or more, further preferably 2 or more, particularly preferably 6 or more, and most preferably 12 or more. Further, the upper limit value of the average added mole number is more preferably 480 or less, still more preferably 450 or less, particularly preferably 420 or less, and most preferably 400 or less.

When the average addition mole number of the oxyalkylene group in the polyhydric alcohol alkylene oxide adduct is outside the above range, the effect of the polycarboxylic acid copolymer having excellent fluidity such as a cement composition is sufficiently obtained. There is a risk that it will not be demonstrated. The "average number of moles of oxyalkylene group added in the polyhydric alcohol alkylene oxide adduct" is an oxyalkylene added in 1 mol of a group formed by the oxyalkylene group of the polyhydric alcohol alkylene oxide adduct. Meaning the average number of moles of groups or the average value of the number of moles of oxyalkylene groups added to 1 mole of hydroxyl groups of the polyhydric alcohol that will form the polyhydric alcohol alkylene oxide adduct. .

In the polyhydric alcohol alkylene oxide adduct, at least one terminal of the oxyalkylene group having a structure bonded to the polyhydric alcohol residue is preferably a hydroxyl group. More preferably, the terminals formed by the oxyalkylene group are all hydroxyl groups.

The weight average molecular weight of the polyhydric alcohol alkylene oxide adduct is not particularly limited, but is preferably 500 to 500,000. The lower limit of the weight average molecular weight is more preferably 1000 or more, still more preferably 5000 or more, particularly preferably 8000 or more, and most preferably 10,000 or more. The upper limit of the weight average molecular weight is more preferably 300000 or less, still more preferably 200000 or less, particularly preferably 100000 or less, and most preferably 80000 or less.

One of the preferable embodiments of the present invention is that the alkylene oxide adduct obtained by adding an oxyalkylene group to the compound having 3 or more active hydrogens is a thioalcohol alkylene oxide adduct.
The thioalcohol alkylene oxide adduct (sometimes referred to as thioalcohol alkylene oxide adduct (A ″) or adduct (A ″)) will be described below. In the adduct (A ″), (A ″) is a mere symbol given to distinguish it from a superordinate concept.
The thioalcohols mean compounds having 3 or more sulfanyl groups per molecule on average, and there is no particular limitation on the specific form thereof. The thioalcohols are preferably compounds composed of four atoms of carbon, hydrogen, oxygen, and sulfur. Examples of the thioalcohols include thioglycolic acid derivatives such as trimethylolpropane tristhioglycolate and pentaerythritol tetrakisthioglycolate, and / or trimethylolpropane tristhiopropionate and pentaerythritol tetrakisthiopropionate. Such mercaptopropionic acid derivatives are suitable, and one or more of these can be used.

Since the adduct (A ″) has an average of 3 or more sulfanyl groups per molecule, an oxyalkylene group can be added in the same manner as the adduct (A ′). The effects of the present invention can be exerted in the same manner as the product (A ′). For the same reason, the description regarding the adduct (A ′) is applied as a preferred form of the adduct (A ″). be able to. When the description relating to the adduct (A ′) is applied to the adduct (A ″), it may be applied as appropriate, for example, by replacing polyhydric alcohol with thioalcohol and replacing the hydroxyl group with sulfanyl group. it can.
In addition, 1 type (s) or 2 or more types of the said adduct (A), the said adduct (A '), and / or the said adduct (A ") can be used as said adduct (X).

The cement admixture of the present invention can be suitably applied to various cement compositions and the like, and can be made to have a viscosity that makes it easy to work in the field where it is handled. By using this cement admixture, the water reduction of the cement composition is improved, the strength and durability of the cured product are improved, and the viscosity becomes easy to work in the field where the cement composition is handled. Therefore, work efficiency and the like in constructing civil engineering and building structures will be improved.

Since the cement admixture of the present invention has the above-described configuration, the fluidity is maintained while enhancing the slump retention property of the cement composition such as cement paste, mortar, and concrete, and the cement composition is handled. It is possible to make the viscosity easy to work on site.

The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by weight” and “%” means “% by mass”.

Production Example 1
Production example of intermediate (a) 614 g of commercially available polyethyleneimine (number average molecular weight 600; ethyleneimine addition number 14) and 4 g of sodium hydride were placed in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer while stirring. After sufficiently substituting with nitrogen, the temperature was raised to 150 ° C. Next, 1886 g of ethylene oxide (average addition number of 3 moles relative to polyethyleneimine active hydrogen) was reacted while being slowly added, and all were added and then aged for 30 minutes at the same temperature to obtain 2500 g of a polyalkyleneimine alkylene oxide compound. Obtained. This compound was defined as an intermediate (a).
Example of production of intermediate (b) 474 g of intermediate (a) was placed in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, and sufficiently substituted with nitrogen while stirring. . Next, 2026 g of ethylene oxide (average addition number of 20 moles relative to polyethyleneimine active hydrogen) was allowed to react while slowly adding, and after adding all, the mixture was aged at the same temperature for 30 minutes to obtain 2500 g of a polyalkyleneimine alkylene oxide compound. Obtained. This compound was defined as an intermediate (b).
Further, 473 g of the intermediate (b) was put in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, and sufficiently substituted with nitrogen while stirring. Next, 2028 g of ethylene oxide (average addition number: 110 mol with respect to polyethyleneimine active hydrogen) was allowed to react slowly, and after adding all, the mixture was aged at the same temperature for 30 minutes to give 2500 g of polyalkyleneimine alkylene oxide compound. Obtained. This compound was defined as <P14-110>.

Production Example 2
<P14-110> 2334 g obtained in Production Example 1 was placed in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, and sufficiently substituted with nitrogen while stirring, and then the temperature was raised to 130 ° C. Next, 166 g of propylene oxide (average addition number 6 mol with respect to polyethylenimine active hydrogen) was slowly added and reacted, and after all was added, the mixture was aged at the same temperature for 5 hours to obtain 2500 g of a polyalkyleneimine alkylene oxide compound. Obtained. This compound was defined as <P14-110-006>.

Production Examples 3-7, 30-36
A polyalkyleneimine alkylene oxide adduct shown in Table 1 was obtained in the same manner as in Production Example 1 or Production Example 2 except that the average number of moles of addition of ethyleneimine, alkylene oxide, etc. was as shown in Table 1. In the table, EIn indicates the average addition number of ethyleneimine, en1, en2 indicate the average addition number of ethylene oxide with respect to polyethyleneimine active hydrogen, and pn indicates the propylene oxide concentration with respect to polyethyleneimine active hydrogen. Indicates the average addition number. As the molecular weight of polyethyleneimine, those corresponding to EIn listed in Table 1 were used. PO mass% in the table indicates mass% of propylene oxide with respect to 100 mass% of alkylene oxide.

Production Example 8
Production Example of Intermediate (c) 312 g of the intermediate (a) obtained in Production Example 1 was placed in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, and sufficiently substituted with nitrogen while stirring. The temperature was raised to 130 ° C. Next, 620 g of propylene oxide (addition number 6 mol with respect to polyethyleneimine active hydrogen) was allowed to react slowly, and after all was added, the mixture was aged at the same temperature for 5 hours. Next, after the temperature was raised to 150 ° C., 1568 g of ethylene oxide (average addition number of 20 moles relative to polyethyleneimine active hydrogen) was allowed to react while slowly adding, followed by aging at the same temperature for 30 minutes. To obtain 2500 g of a polyalkyleneimine alkylene oxide compound. This compound was defined as an intermediate (c).

Furthermore, 464 g of the intermediate (c) was placed in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, and after sufficiently replacing with nitrogen while stirring, the temperature was raised to 150 ° C. Next, 2036 g of ethylene oxide (average number of additions of 90 mol with respect to polyethyleneimine active hydrogen) was allowed to react slowly, and all were added, followed by aging at the same temperature for 30 minutes to obtain 2500 g of polyalkyleneimine alkylene oxide compound. Obtained. This compound was designated as <P14-003-006-160>.

Production Examples 7, 9-21
Polyalkyleneimine alkylene oxide adducts shown in Table 1 were obtained in the same manner as in Production Examples 1 to 2 or 8, except that the average number of moles of addition of ethyleneimine and alkylene oxide was as shown in Table 1. In the table, EIn indicates the average addition number of ethyleneimine, en1, en2 indicate the average addition number of ethylene oxide with respect to polyethyleneimine active hydrogen, and pn indicates the propylene oxide concentration with respect to polyethyleneimine active hydrogen. Indicates the average addition number. As the molecular weight of polyethyleneimine, those corresponding to EIn listed in Table 1 were used. PO mass% in the table indicates mass% of propylene oxide with respect to 100 mass% of alkylene oxide.

Production Example 22
<P14-003-006-160> 2390 g obtained in Production Example 8 was placed in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, and after sufficiently replacing with nitrogen while stirring, the temperature was increased to 130 ° C. The temperature rose. Next, 110 g of propylene oxide (addition number 6 mol with respect to polyethyleneimine active hydrogen) was allowed to react slowly, all were added and then aged at the same temperature for 5 hours to obtain 2500 g of a polyalkyleneimine alkylene oxide compound. It was. This compound was designated as <P14-003-006-160-006>.

Production Example 28
1323 g of <P14-003-006-160> obtained in Production Example 8 was placed in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, and after sufficiently replacing with nitrogen while stirring, the temperature was increased to 130 ° C. The temperature rose. Next, 1177 g of ethylene oxide (average addition number 160 mol with respect to polyethyleneimine active hydrogen) was reacted while being slowly added, and all were added and then aged at the same temperature for 30 minutes to obtain 2500 g of a polyalkyleneimine alkylene oxide compound. Obtained. This compound was designated as <P14-003-006-160-006-160>.

Production Examples 23 to 27, 29
The polyalkyleneimine alkylene oxide adduct shown in Table 1 was prepared in the same manner as in Production Examples 1-2, 8, 22, or 28 except that the average number of moles of addition of ethyleneimine, alkylene oxide, etc. was as shown in Table 1. Obtained. In the table, EIn indicates the average addition number of ethyleneimine, en1, en2 indicate the average addition number of ethylene oxide with respect to polyethyleneimine active hydrogen, and pn indicates the propylene oxide concentration with respect to polyethyleneimine active hydrogen. Indicates the average addition number. As the molecular weight of polyethyleneimine, those corresponding to EIn listed in Table 1 were used. PO mass% in the table indicates mass% of propylene oxide with respect to 100 mass% of alkylene oxide.

Production Example 39
207 g of intermediate (b) was placed in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, and after sufficiently replacing with nitrogen while stirring, the temperature was raised to 130 ° C. Next, 2293 g of a mixed solution of 989 g of ethylene oxide and 1304 g of propylene oxide (average number of additions of 200 mol with respect to polyethyleneimine active hydrogen) was allowed to react while slowly adding, and after aging, the mixture was aged at the same temperature for 5 hours. 2500 g of a polyalkyleneimine alkylene oxide compound was obtained. This compound was defined as <P14-020- (100 + 100)>.

Production Examples 37 to 38, 40 to 42
Polyalkyleneimine alkylene oxide addition shown in Table 2 is the same as Production Examples 1-2, 8, 22, 28, or 39 except that the average number of moles of addition of ethyleneimine, alkylene oxide, etc. is as shown in Table 1. I got a thing. In Tables 1 and 2 below, EIn represents the average addition number of ethyleneimine, en1 and en2 represent the average addition number of ethylene oxide to polyethyleneimine active hydrogen, and pn represents the polyethyleneimine active hydrogen. The average addition number of all propylene oxide is shown. As the molecular weight of polyethyleneimine, those corresponding to EIn listed in Table 1 were used. PO mass% in the table indicates mass% of propylene oxide with respect to 100 mass% of alkylene oxide.

The meaning of () in the table represents a random polymer in which ethylene oxide and propylene oxide are mixed and added in the proportions described in (). For example, (100 + 100) described in Production Example 39 is a random polymer added by mixing an amount corresponding to 100 mol of ethylene oxide and an amount corresponding to 100 mol of propylene oxide.

Production Example 43 <Production of Intermediate (d)>
In a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, 409 g of isoprenol and 0.6 g of sodium hydroxide were placed, and after sufficiently replacing with nitrogen, the temperature was raised to 130 ° C. while stirring. Next, 2091 g (average number of additions of 10 mol) of ethylene oxide was reacted while being slowly added, and all were added, followed by aging at the same temperature for 30 minutes to obtain 2500 g of an isoprenol ethylene oxide compound. This compound was defined as <intermediate (d)>.

Production Example 44 <Production of IPN-50>
575 g of the intermediate (d) obtained in Production Example 43 was placed in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, and after sufficiently replacing with nitrogen, the temperature was raised to 130 ° C. while stirring. Next, 1925 g (average addition number 40 mol) of ethylene oxide was reacted while being slowly added, and after adding all, the mixture was aged at the same temperature for 30 minutes to obtain 2500 g of an isoprenol ethylene oxide compound. This compound was defined as <IPN-50>.

Production Example 45
A reactor equipped with a thermometer, a stirrer, a dropping device, a nitrogen introduction tube, and a cooling tank was charged with <IPN-50> 1262 g obtained in Production Example 44 and water 746 g, and the mixture was stirred at 58 ° C. in a nitrogen atmosphere while stirring. The temperature was raised to. Subsequently, after adding 3.7 g of 30% hydrogen peroxide, 253.7 g of a solution obtained by mixing 78.4 g of acrylic acid and 175.3 g of distilled water was added for 3 hours, and 1.4 g of L-ascorbic acid, 3-mercapto 232.5 g of a solution in which 3.5 g of propionic acid and 227.6 g of distilled water were mixed was added dropwise over 3.5 hours. Then, it stirred for 1 hour, keeping at 58 degreeC, and the polymerization reaction was completed. After cooling, an aqueous sodium hydroxide solution was added to adjust the pH to 7 to obtain an aqueous solution of polymer (I) containing 92.5% by mass of IPN-50. Table 3 shows the composition and weight average molecular weight of the polymer (A).

Production Example 46 <Production of esterified product (a)>
In a reactor equipped with a thermometer, a stirrer, a nitrogen inlet tube, and a condensation water separator, 2033 g of poly (n = 25) ethylene glycol monomethyl ether, 400 g of methacrylic acid, 54 g of paratoluenesulfonic acid monohydrate, phenothiazine 0. 5 g and 243 g of cyclohexane as an azeotropic solvent were charged, and while maintaining at 115 ° C., the condensed water was separated and heated for 20 hours for esterification. At an esterification rate of 99% (conversion rate of polyethylene glycol monomethyl ether), after adding 509 g of distilled water and 42 g of 30% sodium hydroxide solution, the temperature was raised again, and cyclohexane was removed by azeotropic distillation. Was added to obtain an aqueous solution of a mixture containing 70% esterified product (a) and 10% unreacted methacrylic acid.

Production Example 47
A reactor equipped with a thermometer, a stirrer, a dropping device, a nitrogen introduction tube, and a cooling tank was charged with 50 g of distilled water, and the temperature was raised to 80 ° C. while stirring in a nitrogen atmosphere. Subsequently, a solution in which 215.9 g of a mixture of the esterified product (a) obtained in Production Example 46 and methacrylic acid, 12.8 g of methacrylic acid, 69.8 g of distilled water, and 1.5 g of 3-mercaptopropionic acid were mixed. For 4 hours, and a solution prepared by mixing 47.9 g of distilled water and 2.1 g of ammonium persulfate was added dropwise over 5 hours. Thereafter, the mixture was aged for 1 hour while being kept at 80 ° C., then cooled, added with 30% aqueous sodium hydroxide solution, adjusted to pH 7, and further added with distilled water to have a weight average molecular weight of 25000, and esterified product (a) A polymer (b) having 80% by mass of the derived site was obtained. Table 3 shows the composition and weight average molecular weight of the polymer (b).

Production Example 48 <Production of H- (OC2H4) 13- (OC3H6) 2- (OC2H4) 10-OCH3>
1100 g of poly (n = 10) ethylene glycol monomethyl ether and 0.5 g of potassium hydroxide were charged into a reactor equipped with a thermometer, a stirrer, a raw material introducing tank, and a nitrogen introducing tube, and the inside of the reactor was purged with nitrogen. The temperature was raised to 0 ° C., and 235 g of propylene oxide was added over 3 hours while maintaining this temperature. After the addition, the mixture was further aged at 120 ° C. for 2 hours, and the inside of the reactor was again purged with nitrogen. Then, 1165 g of ethylene oxide was added over 3 hours while maintaining the temperature at 120 ° C. After the addition, the mixture was further aged at 120 ° C. for 1 hour to obtain alkylene glycol monomethyl ether having a hydroxyl value of 48 mg · KOH / g.

Production Example 49 <Production of esterified product (b)>
In a reactor equipped with a thermometer, a stirrer, a nitrogen inlet tube, and a condensed water separator, 2083 g of the polyalkylene glycol monomethyl ether obtained in Production Example 48, 350 g of methacrylic acid, 54 g of paratoluenesulfonic acid monohydrate, phenothiazine 0.5 g and 243 g of cyclohexane as an azeotropic solvent were charged, and while maintaining at 115 ° C., condensed water was separated and heated for 28 hours for esterification. At an esterification rate of 99% (conversion rate of polyalkylene glycol monomethyl ether), after adding 510 g of distilled water and 41 g of 30% sodium hydroxide solution, the temperature was raised again, and cyclohexane was removed by azeotropic distillation. Water was added to obtain an aqueous solution of a mixture containing 72% esterified product (b) and 8% unreacted methacrylic acid.

Production Example 50
A reactor equipped with a thermometer, a stirrer, a dropping device, a nitrogen introduction tube, and a cooling tank was charged with 50 g of distilled water, and the temperature was raised to 80 ° C. while stirring in a nitrogen atmosphere. Subsequently, a solution in which 200.0 g of a mixture of the esterified product (b) obtained in Production Example 49 and methacrylic acid, 25.2 g of methacrylic acid, 71.3 g of distilled water, and 3.5 g of 3-mercaptopropionic acid were mixed. For 4 hours, and a solution prepared by mixing 47.9 g of distilled water and 2.1 g of ammonium persulfate was added dropwise over 5 hours. Thereafter, the mixture was aged for 1 hour while being kept at 80 ° C., then cooled, added with 30% aqueous sodium hydroxide solution, adjusted to pH 7, and further added with distilled water to have a weight average molecular weight of 14,000, and esterified product (a) A polymer (c) having 75% of the site of origin was obtained. Table 3 shows the composition and weight average molecular weight of the polymer (c).

In Table 3, “SA” is sodium acrylate, “SMAA” is sodium methacrylate, “PGM-10E2P13E” is an esterified product (a), and “PGM-25E” Is an esterified product (b).

Example 1-46 and Comparative Example 1-6
(Mortar test method)
Using the cement admixture prepared by adjusting the components shown in Tables 1 to 3 with the combinations and amounts shown in Table 4, mortar tests were conducted under the compounding conditions shown in Table 5. That is, cement (C), fine aggregate (S1) and fine aggregate (S2) are put into a mortar mixer, and kneaded at low speed for 10 seconds, and kneaded water containing cement admixture and air amount adjusting agent (W ) And kneaded at a low speed for 60 seconds, and after the kneading was stopped, the mortar adhered to the wall surface of the mixer was scraped off over 30 seconds, and further kneaded at a high speed for 90 seconds to produce a mortar. The manufactured mortar was packed into a mini slump cone, pulled up vertically, and the slump value immediately after kneading was measured. Similarly, the slump value after 60 minutes was also measured, and the holding property was evaluated by the slump loss rate immediately after kneading. As the shape of the mini slump cone, an upper end inner diameter of 50 mm, a lower end inner diameter of 100 mm, and a height of 150 mm were used. Moreover, the usage-amounts of the cement admixture and the air amount adjusting agent were adjusted so that the mortar slump value immediately after kneading was 8 to 10 cm and the air amount was 3 to 5%. The evaluation of the slump retention property was evaluated with ○ when the slump loss rate after 60 minutes was less than 30% and × when 30% or more. The evaluation results are shown in Table 4. The slump loss rate (%) is expressed as a value obtained by subtracting the slump value after 60 minutes from the slump value immediately after kneading and dividing by the slump value immediately after kneading and multiplying by 100.

The materials used in Table 4 are as follows.
Cement (C): Ordinary Portland cement <Pacific cement company>
Fine aggregate (S1): Standard sand for cement strength test <JIS R 5201>
Fine aggregate (S2): Toyoura standard sand Air volume regulator: MA404
MA303A <AE agent, manufactured by Pozoris Bussan>

From Table 5, the slump retention property of the mortar using the cement admixture in which the polyalkyleneimine alkylene oxide adduct (A) and the polymer (B) are used in combination is only the polymer (B) as a comparative example. Compared with the case where it was used as, the results were all good.

Examples 47-50 and Comparative Examples 7-10
(Concrete test method)
Using the cement admixture prepared by adjusting the components shown in Tables 1 to 3 with the combinations and blending amounts shown in Table 7, concrete tests were conducted under the blending conditions shown in Table 6. That is, using a 100 L forced pan mixer, cement (C), fine aggregate (S), and coarse aggregate (G) are added and kneaded for 10 seconds, including a cement admixture and an air amount adjusting agent. Kneading water (W) was added and kneaded to produce concrete. Using the manufactured concrete, the slump value immediately after kneading, after 15 minutes and after 30 minutes was also measured according to JIS A 1101, and the retention was evaluated by the slump loss ratio immediately after kneading. Moreover, the usage-amount of the cement admixture and the air amount adjusting agent was adjusted so that the slump value immediately after kneading might be 19-21 cm and the air amount would be 3-5%. The evaluation of the slump retention property was evaluated by ○ when the slump loss rate after 30 minutes was less than 30%, and × when 30% or more. Table 7 shows the evaluation results. The slump loss rate calculation formula is the same as described above.

The materials used in Table 6 are as follows.
Cement (C): 3 types of ordinary Portland cement mixed <Pacific Cement, Sumitomo Osaka Cement, Ube Mitsubishi Cement>
Coarse aggregate (G): Ome hard crushed stone density 2.65
Fine aggregate (S2): Mountain sand from Chiba Prefecture Density 2.59 FM value 2.22
Air amount adjusting agent: MA404 <Antifoaming agent, manufactured by Pozoris Bussan>
MA303A <AE agent, manufactured by Pozoris Bussan>

Table 7 will be described below. In the table, the admixture / cement (mass%) represents the mass ratio (mass%) of the cement admixture to the cement. LSN represents sodium lignin sulfonate.
From Table 7, the slump retention property of the concrete using the cement admixture in which the polyalkyleneimine alkylene oxide adduct (A) and the polymer (B) are used in combination is only the polymer (B) as a comparative example. Compared with the case where it was used as an admixture, the results were all good. In addition, the slump retention of concrete using a sulfonic acid compound (C) instead of the polymer (B) and a cement admixture used in combination with the polyalkyleneimine alkylene oxide adduct (A) is a comparative example. Compared with the case where only a certain sulfonic acid type compound (C) was used as a cement admixture, all were good results.

Production Examples 51-55
Polyalkyleneimine alkylene oxide adducts shown in Table 8 below are obtained in the same manner as in Production Example 1-2 and Production Example 8, except that the average number of moles of addition of ethyleneimine, alkylene oxide, etc. is as shown in Table 8 below. It was. In Table 8 below, EIn represents the average addition number of ethyleneimine, en1 and en2 represent the average addition number of ethylene oxide to polyethyleneimine active hydrogen, and pn represents the polyethyleneimine active hydrogen. The average addition number of propylene oxide is shown. As the molecular weight of polyethyleneimine, those corresponding to EIn listed in Table 1 were used. PO mass% in the table indicates mass% of propylene oxide with respect to 100 mass% of alkylene oxide.

Production Example 56
Production Example of Intermediate (e) 193 g of commercially available D-sorbitol (abbreviation: SB) and 1.5 g of sodium hydroxide were placed in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer. After sufficient substitution, the temperature was raised to 150 ° C. Next, 2807 g of ethylene oxide (average addition number of 10 mol with respect to the active hydrogen of SB) was reacted while slowly added, and all were added and then aged at the same temperature for 30 minutes to obtain 3000 g of SB-ethylene oxide adduct. It was. This compound was defined as an intermediate (e).

Production Example of Intermediate (f) 434 g of Intermediate (e) and 0.78 g of sodium hydroxide were placed in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, and sufficiently substituted with nitrogen while stirring. The temperature was raised to 130 ° C. Next, 327 g of propylene oxide (average addition number 6 mol with respect to active hydrogen of SB) was allowed to react while slowly adding, and after adding all, aging was performed at the same temperature for 3 hours. Next, after raising the temperature to 150 ° C., 1239 g of ethylene oxide (average addition number of 30 mol with respect to SB active hydrogen) was slowly added and reacted, and after adding all, 30 minutes at the same temperature. After aging, 2000 g of SB-ethylene oxide adduct was obtained. This compound was defined as an intermediate (f).
Further, 575 g of the intermediate (f) and 0.68 g of sodium hydroxide were placed in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, and after sufficiently replacing with nitrogen while stirring, the temperature was raised to 150 ° C. Warm up. Next, 1425 g of ethylene oxide (average addition number of 120 mol with respect to the active hydrogen of SB) was reacted while being slowly added, and all were added and then aged for 30 minutes at the same temperature to obtain 2000 g of SB-ethylene oxide adduct. It was. This compound was defined as <SB-10-006-150>.

Production Examples 57-59
SB-alkylene oxide adducts shown in Table 9 were obtained in the same manner as in Production Example 56 except that the average number of moles added to SB was as shown in Table 9.

Production Example 60 <Production of Polymer (d)>
A reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen introduction tube, and a cooling tube was charged with 1035 g of the 80% aqueous solution of <IPN-50> obtained in Production Example 44 and 300 g of water, and stirred in a nitrogen atmosphere. The temperature was raised to 58 ° C. Next, 71.4 g of a solution obtained by mixing 26.4 g of acrylic acid and 45 g of distilled water for 5 hours, 86 g of a solution obtained by mixing 3.5 g of sodium persulfate and 82.5 g of distilled water, and L-ascorbic acid 91 g of a solution in which 1.0 g and 90 g of distilled water were mixed was added dropwise over 5.5 hours. Then, it stirred for 1 hour, keeping at 58 degreeC, and the polymerization reaction was completed. After cooling, an aqueous sodium hydroxide solution was added to adjust the pH to 7 to obtain an aqueous solution of polymer (d) containing 96% by mass of IPN-50. Table 3 shows the composition and weight average molecular weight of the polymer (d).

Production Example 61 <Production of MLA-10>
Into a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, 710 g of methallyl alcohol and 2.5 g of sodium hydroxide were put, and after sufficiently replacing with nitrogen while stirring, the temperature was raised to 125 ° C. Subsequently, 868 g (average addition number 2 mol) of ethylene oxide was allowed to react while being slowly added, and after all was added, the temperature was raised to 150 ° C. Furthermore, 3470 g (average addition number 8 mol) of ethylene oxide was reacted while being slowly added, and after adding all, the mixture was aged at the same temperature for 60 minutes to obtain 2.5 kg of a methallyl alcohol ethylene oxide compound. This compound was defined as <MLA-10>.

Production Example 62 <Manufacture of MLA-50>
<MLA-10> 2217 g and sodium hydroxide 3.81 g were placed in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, and sufficiently substituted with nitrogen while stirring, and then the temperature was raised to 150 ° C. . Subsequently, 7621 g of ethylene oxide (average number of additions of 40 mol) was allowed to react while slowly adding, and after adding all, the mixture was aged at the same temperature for 60 minutes to obtain 9.8 kg of a methallyl alcohol ethylene oxide compound. This compound was defined as <MLA-50>.

Production Example 63 <Production of MLA-100>
In a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, 5050 g of <MLA-50> and 2.46 g of sodium hydroxide were placed, and after sufficiently replacing with nitrogen while stirring, the temperature was raised to 150 ° C. . Next, 4890 g (average addition number 50 mol) of ethylene oxide was reacted while being slowly added, and after adding all, the mixture was aged at the same temperature for 60 minutes to obtain 9.9 kg of a methallyl alcohol ethylene oxide compound. This compound was defined as <MLA-100>.

Production Example 64 <Production of polymer (e)>
A reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen introducing tube, and a cooler was charged with 1255 g of an 80% aqueous solution of <MLA-100> obtained in Production Example 63 and 245 g of water, and stirred in a nitrogen atmosphere. The temperature was raised to 58 ° C. Next, 300 g of a solution obtained by mixing 85.4 g of acrylic acid and 214.6 g of distilled water for 5 hours, 100 g of a solution obtained by mixing 6.7 g of sodium persulfate and 93.3 g of distilled water, and L-ascorbic acid 100 g of a solution in which 1.9 g, 2.2 g of 3-mercaptopropionic acid and 95.9 g of distilled water were mixed was added dropwise over 5.5 hours. Then, it stirred for 1 hour, keeping at 58 degreeC, and the polymerization reaction was completed. After cooling, an aqueous sodium hydroxide solution was added to adjust the pH to 7 to obtain an aqueous solution of a polymer (e) containing 90% by mass of MLA-100. Table 3 shows the composition and weight average molecular weight of the polymer (e).

Production Example 65 <Production of polymer (f)>
A reactor equipped with a thermometer, a stirrer, a dropping device, a nitrogen introduction tube, and a cooler was charged with 1860 g of the 80% aqueous solution of <IPN-50> obtained in Production Example 44 and 505 g of water, and the mixture was stirred in a nitrogen atmosphere. The temperature was raised to 60 ° C. Next, 130 g of melted maleic anhydride was added all at once, the temperature was raised to 63 ° C., and 200 g of a solution in which 1.7 g of L-ascorbic acid and 198.3 g of distilled water were mixed was added dropwise over 1 hour. . Thereafter, the mixture was stirred for 1 hour while maintaining the temperature at 63 ° C. to complete the polymerization reaction. After cooling, an aqueous sodium hydroxide solution was added to adjust the pH to 7 to obtain an aqueous solution of a polymer (F) containing 87.5% by mass of <IPN-50>. Table 3 shows the composition and weight average molecular weight of the polymer (f).

Examples 51-78, Comparative Examples 11-20, and Reference Example 1
(Concrete test method)
A concrete test was conducted under the blending conditions shown in Table 10 using cement admixtures prepared by adjusting the components shown in Tables 8 to 10 with combinations and blending amounts shown in Table 11. That is, using a 100 L forced pan mixer, cement (C), fine aggregate (S), and coarse aggregate (G) are added and kneaded for 10 seconds, including a cement admixture and an air amount adjusting agent. Kneading water (W) was added and kneaded to produce concrete. Using the manufactured concrete, the slump value immediately after kneading, after 15 minutes and after 30 minutes was also measured according to JIS A 1101, and the retention was evaluated by the slump loss ratio immediately after kneading. Moreover, the usage-amount of the cement admixture and the air amount adjusting agent was adjusted so that the slump value immediately after kneading might be 19-21 cm and the air amount would be 3-5%. The evaluation of the slump retention is ◎ when the slump loss rate after 15 minutes is 15% or less, ○ if it exceeds 15% and 20% or less, × if it exceeds 20% and 25% or less, 20% What exceeded 25 and was 25% or less was evaluated by xx. The evaluation results are shown in Table 11 below. The slump loss rate calculation formula is the same as described above.

When there is a difference of about 5% in the slump loss rate as described above, for example, it is possible to expect the effect of significantly maintaining the viscosity of the cement and considerably extending the time that can be easily worked at the site of handling, Thereby, work efficiency and the like are improved. It can be evaluated that such an effect is remarkable in this industry.

Abbreviations used in Tables 1 to 7 have the same meanings in Tables 8 to 11 below. The names of the adduct (X) and polymer (B) described in Table 11 below correspond to the names described in Tables 1-10. For example, in Table 11, it is described that the name of the adduct (X) used in Examples 67 to 70 is SB-010-006-150, which is an addition synthesized in Production Example 56. It means that the cement admixture was prepared using the product (X).

Table 8 will be described below. In Table 8 above, EIn represents the average number of moles of ethyleneimine, and in the present invention, this number is defined as the number of active hydrogens. SB represents D-sorbitol. The number of active hydrogens in D-sorbitol is 6.

Table 9 will be described below. In Table 9 above, SMA represents anhydrous maleate.

Table 10 will be described below. The materials used in Table 10 are as follows.
Cement (C): 2 types of ordinary Portland cement mixed (manufactured by Taiheiyo Cement / Ube Mitsubishi Cement = 80/20)
Coarse aggregate (G): Ome hard crushed stone density 2.65
3 classification blend 5-10 mm / 10-15 mm / 15-20 mm = 30/30/40 (volume%) 5 mm or less and 20 mm or more were cut.
Fine aggregate (S1): Kakegawa land sand density 2.59 FM value 2.19
Fine aggregate (S2): Mountain sand from Chiba Prefecture density 2.61 FM value 2.22
Air amount adjusting agent: MA404 <Antifoaming agent, manufactured by Pozoris Bussan>
Air amount adjusting agent: MA303A <antifoaming agent, manufactured by Pozoris Bussan>

Table 11 will be described below. In the table, LSN represents sodium lignin sulfonate. The admixture / cement (wt%) means the mass ratio of the cement admixture to the cement, and indicates the amount of the cement admixture used. MA303A represents an AE agent. MA404A represents an antifoaming agent.

In Table 11, as described above, the slump retention was evaluated based on the slump loss rate in four stages of ◎, ○, ×, and XX. In addition, about the slump retainability evaluation by the above four-step evaluation, even if the evaluation by the four-step evaluation is the same, it does not necessarily mean that there is no difference in the slump retainability in all the examples having the same evaluation. It is not a thing. In the measurement of the slump loss rate, it has been experimentally known that a measurement error of about ± 1% occurs under the same conditions. If there is a difference of 2% or more, it may not be an error. Is considered high. Therefore, even if the slump retention evaluation is the same, if there is a difference of 2% or more in the slump loss rate, it may be determined that the smaller the slump loss rate, the higher the superiority. When there is a difference of 2% or more in the slump loss rate as described above, for example, it is possible to expect the effect of keeping the viscosity of the cement good and extending the time that can be easily worked in the handling site, thereby Thus, work efficiency and the like will be improved. It can be evaluated that such an effect is remarkable in this industry.

When Examples 52 to 54 and Comparative Examples 11 to 13 are compared, the technical significance by setting the total average number of added moles of oxyalkylene groups to 1 mole of active hydrogen is 100 moles or more. Each of the cement admixtures of Comparative Examples 11 to 13 is a cement admixture comprising an adduct prepared by adjusting an average addition mole number of oxyalkylene groups to 89 moles to polyalkyleneimine. Examples 52 to 54 The slump retention was inferior to that of the cement admixture. That is, it was found that the slump retention property of the cement admixture can be sufficiently improved by setting the total average number of added moles of oxyalkylene groups to 1 mole of the active hydrogen. The same can be said for the polyhydric alcohol alkylene oxide adducts by comparing Examples 72 to 74 and Comparative Examples 18 to 20.

Further, when Example 66 and Reference Example 1 are compared, the technical significance of mainly using an unsaturated monocarboxylic acid monomer in the synthesis of the polycarboxylic acid polymer (B), that is, a polyvalent carboxylic acid. The technical significance of reducing the amount of acid used as much as possible is clear. The cement admixture of Reference Example 1 is a polymer (f) prepared using 12.5% by mass of maleic anhydride in 100% by mass of all monomer components as the polycarboxylic acid polymer (B). It was prepared in the same manner as in Example 66 except that it was included. However, the cement admixture of Reference Example 1 did not exhibit sufficient slump retention as compared with the cement admixture of Example 66. Thus, it was found that slump retention can be sufficiently improved by reducing the amount of polyvalent carboxylic acid used as much as possible.

Furthermore, the technical significance of making the oxyalkylene group having 3 or more carbon atoms indispensable is clear from the comparison between Example 52 and Example 62 and the comparison between Example 67, Example 75, and Example 78. It is. Example 52 is a cement admixture containing an adduct (X) in which an oxyalkylene group having 3 or more carbon atoms is essential and an average addition mole number of the oxyalkylene group is 109. The agent contains an adduct (X) having no oxyalkylene group having 3 or more carbon atoms and having an average addition mole number of oxyalkylene group of 110. Except that Example 52 and Example 62 are different in the structure of the adduct (X) described above, the usage form of the polycarboxylic acid polymer (B) and the sulfonic acid compound (C) are not used. In addition, the blending ratio and the like of each polymer are common, and by comparing these, the technical significance of requiring an oxyalkylene group having 3 or more carbon atoms can be clarified. Example 52 was more excellent in slump retention than Example 62. Even if Example 67, Example 75, and Example 78 are compared, it is the same. Thus, it was found that the slump retention property can be further improved by making the oxyalkylene group having 3 or more carbon atoms essential.

Claims (9)

A cement admixture comprising an alkylene oxide adduct obtained by adding an oxyalkylene group to a compound having 3 or more active hydrogens,
The cement admixture characterized in that the alkylene oxide adduct has a total average added mole number of oxyalkylene groups per mole of active hydrogen of 100 moles or more. The cement admixture according to claim 1, wherein the cement admixture further comprises a polycarboxylic acid polymer. The polycarboxylic acid-based polymer has the following general formula (1):

(In the general formula ^(1), R 1, ^{R 2} and ^{R 3} are the same or different, .R ⁴ represents a hydrogen atom or a methyl group, one or oxyalkylene group having 2 to 4 carbon atoms R ⁵ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, x represents a number from 0 to 2, y represents a number from 0 to 1, m represents oxy This represents the average number of moles added of the alkylene group, and is a number from 2 to 300.)
A monomer unit derived from a polyalkylene glycol unsaturated monomer represented by the following general formula (2);

(In the general formula (2), R ⁶ and R ⁷ are the same or different and each represents a hydrogen atom or a methyl group. M ¹ represents a hydrogen atom, a metal atom, an ammonium group, or an organic amine group.)
The cement admixture according to claim 2, wherein a monomer unit derived from the unsaturated monocarboxylic acid monomer represented by 4. The polycarboxylic acid polymer according to claim 2, wherein an unsaturated monocarboxylic acid monomer is 50 mass% or more in 100 mass% of all components of the carboxylic acid monomer. 5. Cement admixture. A cement admixture comprising an alkylene oxide adduct obtained by adding an oxyalkylene group to a compound having 3 or more active hydrogens and a sulfonic acid compound. The cement admixture according to any one of claims 1 to 5, wherein the compound having three or more active hydrogens has a hydroxyl group and / or an amino group having active hydrogen. The cement admixture according to any one of claims 1 to 6, wherein the alkylene oxide adduct is obtained by adding an alkylene oxide to a polyhydric alcohol and / or polyethyleneimine. The cement admixture according to any one of claims 1 to 7, wherein the alkylene oxide adduct essentially comprises an oxyalkylene group having 3 or more carbon atoms. The cement admixture according to any one of claims 1 to 8, wherein the oxyalkylene group which is a constituent unit of the alkylene oxide adduct is derived from ethylene oxide and propylene oxide.