JP4883901B2 - Cement admixture - Google Patents

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, as for the dispersant for inorganic powder, a water-soluble cocondensate or a water-soluble copolymer into which a random polymer chain of oxypropylene group and / or oxybutylene group and oxyethylene group is introduced is contained as an essential component. Is disclosed (for example, see 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. It is disclosed that the blended cement composition has an excellent water reduction effect (see, for example, Patent Document 2).
However, when it is used for a cement composition or the like, it is not sufficient that water is reduced. That is, 1) Workability at the construction site for civil engineering / building structures, etc. by improving the fluidity retention of concrete, etc. at the production site, and 2) making the concrete, etc. easier to work with There is room for improvement in terms of further improving efficiency, etc., 3) devised to increase the compressive strength of hardened concrete, and 4) reducing the amount of air in ready-mixed concrete using high-performance AE water reducing agent. there were.
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 possible to provide a cement admixture that can not only improve the state of the cement composition and the like, but also reduce the air amount of the cement composition and increase the compressive strength of the cured cement composition. It is the purpose.

The present inventors have made various investigations on cement admixtures required in construction sites for civil engineering and building structures, etc., which can form cement compositions and the like that are fluid and retain excellent workability. As a result, firstly paying attention to the fact that the polycarboxylic acid polymer can exhibit water-reducing performance with respect to the cement composition or the like, and using the polyalkyleneimine alkylene oxide adduct together with the polycarboxylic acid polymer, It has been found that it is effective in improving the viscosity of the composition. Further, among the polyalkyleneimine alkylene oxide adducts, those having an oxyalkylene group having 3 or more carbon atoms as well as reducing the viscosity, as well as cement compositions using conventional high-performance AE water reducing agents, In contrast, the present inventors have found that a cement composition state closer to that of fresh concrete can be achieved, and that the strength of the hardened concrete is further improved.

(1) A polyalkyleneimine alkylene oxide adduct (I) essentially comprising an oxyalkylene group having 3 or more carbon atoms is combined with a polycarboxylic acid polymer (A), followed by addition of a polyalkyleneimine alkylene oxide. The amount of the product (I) is specified, (2) the end of the polyalkyleneimine alkylene oxide adduct (I) having an oxyalkylene group having 3 or more carbon atoms as an essential component is specified as an oxyethylene group, (3 ) To solve the above problem by specifying the oxyalkylene group content of 3 or more carbon atoms in the polyalkyleneimine alkylene oxide adduct (I), which essentially requires an oxyalkylene group of 3 or more carbon atoms. Thus, the present invention has been achieved.

That is, the present invention is a cement admixture comprising a polyalkyleneimine alkylene oxide adduct (I) essentially comprising an oxyalkylene group having 3 or more carbon atoms and a polycarboxylic acid polymer (A), The cement admixture is a cement admixture containing 1 to 45% by mass of the polyalkyleneimine alkylene oxide adduct (I) with respect to 100% by mass of the solid content of the cement admixture.
The present invention also provides a cement admixture comprising a polyalkyleneimine alkylene oxide adduct (I) essentially comprising an oxyalkylene group having 3 or more carbon atoms, wherein the cement admixture comprises the polyalkyleneimine alkylene oxide. It is also a cement admixture in which the end of the adduct (I) is an oxyethylene group.
The present invention further relates to a cement admixture comprising a polyalkyleneimine alkylene oxide adduct (I) essentially comprising an oxyalkylene group having 3 or more carbon atoms, wherein the cement admixture comprises the polyalkyleneimine alkylene oxide. It is also a cement admixture containing 15% by mass or more of an oxyalkylene group having 3 or more carbon atoms with respect to 100% by mass of the oxyalkylene group of the adduct (I).
The present invention is described in detail below.

The cement admixture of the present invention comprises (1) a form containing a polyalkyleneimine alkylene oxide adduct (I) essentially comprising an oxyalkylene group having 3 or more carbon atoms and a polycarboxylic acid polymer (A), (2 ) A form containing a polyalkyleneimine alkylene oxide adduct (I) essentially comprising an oxyalkylene group having 3 or more carbon atoms whose terminal is specified as an oxyethylene group, and (3) an oxyalkylene group content having 3 or more carbon atoms The polyalkyleneimine alkylene oxide adduct (I) essentially comprising an oxyalkylene group having 3 or more carbon atoms specified above is at least one of the three forms.
In these forms, the polycarboxylic acid polymer and the polyalkyleneimine alkylene oxide adduct essentially comprising an oxyalkylene group having 3 or more carbon atoms may be used alone or in combination of the above, The cement admixture of the form (1) preferably comprises two or more polycarboxylic acid polymers. Moreover, in the cement admixture of the said form (2) and (3), it is preferable to further contain a polycarboxylic acid type polymer (A), More preferably, two types of polycarboxylic acid type polymers are included. It is to include the above. In addition, 2 or more types of polycarboxylic acid type | system | group polymers mean that the polycarboxylic acid type polymer from which characteristics, such as an average molecular weight and an alkylene oxide average addition mole number differ, is 2 or more types, for example.

In the following description, these components in the present invention are copolymerized with a polycarboxylic acid polymer (A) (also simply referred to as polymer (A)); a polyalkyleneimine alkylene oxide adduct monomer. A polycarboxylic acid polymer (B) (also simply referred to as polymer (B)); a polycarboxylic acid copolymer (C) having a polyalkylene glycol side chain essentially comprising an oxyalkylene group having 3 or more carbon atoms (Also simply referred to as polymer (C)); polycarboxylic acid-based polymer (D) other than the above polymer (B) and polymer (C) (also simply referred to as polymer (D)); Polyalkyleneimine alkylene oxide adduct (I) (simply referred to as adduct (I)) which requires an oxyalkylene group; an oxyalkylene group having 3 or more carbon atoms whose terminal is specified as an oxyethylene group is essential A polyalkyleneimine alkylene oxide adduct (II) (also simply referred to as an adduct (II)); a polyalkyleneimine alkylene oxide adduct having an oxyalkylene group having 3 or more carbon atoms other than the adduct (II) ( III) (also simply referred to as adduct (III)). The polyalkyleneimine alkylene oxide adduct monomer means a polyalkyleneimine alkylene oxide adduct having a polymerizable unsaturated double bond.
In the above components, the polymer (A) is a polymer that is a superordinate concept of the polymer (B), the polymer (C), and the polymer (D), and the polymer (B) and the polymer (C). The polymer (D) is contained in the polymer (A). Similarly, the adduct (II) and the adduct (III) are included in the adduct (I).

In the present invention, the cement admixture of the above-mentioned form (1) includes a polyalkyleneimine alkylene oxide adduct (I) essentially comprising an oxyalkylene group having 3 or more carbon atoms, a polycarboxylic acid polymer (A), For example,
Combination with adduct (I) + polymer (B),
Combination with adduct (I) + polymer (C),
Combination with adduct (I) + polymer (D),
A combination of adduct (I) + polymer (B) + polymer (D),
Combinations of adduct (I) + polymer (C) + polymer (D) and the like can be mentioned.

The cement admixture of the above form (2) includes a polyalkyleneimine alkylene oxide adduct (II) essentially having an oxyalkylene group having 3 or more carbon atoms, the terminal of which is specified as an oxyethylene group.
A combination of adduct (II) + adduct (III),
Combination with adduct (II) + polymer (A),
Combinations of adduct (II) + adduct (III) + polymer (A) and the like can be mentioned.

Any of these combinations is a preferred form of the present invention, but more preferably a form using two or more of the polycarboxylic acid polymers (A) as described above.

In the cement admixture of the above form (1), it is appropriate that the adduct (I) is contained in an amount of 1% by mass to 45% by mass with respect to 100% by mass of the solid content of the cement admixture. is there. If it is less than 1% by mass, the viscosity of the cement composition or the like may not be sufficiently improved, and if it exceeds 45% by mass, sufficient strength cannot be imparted to the cement composition, Moreover, there is a possibility that the dispersibility cannot be sufficiently improved, and there is a possibility that it becomes economically disadvantageous. More preferably, it is 2% by mass or more and 45% by mass or less, more preferably 3% by mass or more, and 40% by mass or less, and particularly preferably 4% by mass or more. Moreover, it is 35 mass% or less, Most preferably, it is 5 mass% or more, and is 30 mass% or less.
In addition, although it is preferable that the cement admixture of the said form (2) and (3) also contains a polycarboxylic acid type polymer (A) as mentioned above, in this case, as an adduct (I), Similarly to the above-described form (1), the content is preferably 1% by mass or more and 45% by mass or less, and more preferable upper limit value and lower limit value are also as described above.
Here, in the cement admixture of the present invention, the total amount of the solids of the adduct (I) and the polymer (A) in the cement admixture is preferably 100% by mass and adjusted to the amount used.

In the cement admixtures of the above forms (1) to (3), the adduct (I) essentially contains an oxyalkylene group having 3 or more carbon atoms. It is possible to improve the compressive strength of the hardened cement composition and the like while making it better. 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 1% by mass or more with respect to 100% by mass of the total amount of oxyalkylene groups in the adduct (I) Preferably it is. More preferably, it is 5 mass% or more, More preferably, it is 10 mass% or more, Especially preferably, it is 15 mass% or more, Most preferably, it is 20 mass% or more. Moreover, it is suitable that it is 70 mass% or less. If it exceeds 70% 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 60 mass% or less, Especially preferably, it is 50 mass% or less, Most preferably, it is 40 mass% or less.

In the adduct (I), 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. By making the oxypropylene group essential, the state of the cement composition and the like can be improved, and the effect of the present invention of further improving the compressive strength of the cured cement composition and the like can be sufficiently exhibited. It becomes possible.
The adduct (I) 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 ABA type (A: This is a form having a block copolymer structure of (oxyethylene group, B: oxypropylene group).
The adduct (I) preferably further has an oxyethylene group at its end, which improves hydrophilicity and makes it possible to sufficiently increase water reduction.

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 (I) with respect to the solid content of the cement admixture and a method for measuring the solid content ratio of the polymer (B) with respect to the solid content of the cement admixture, the following methods are preferable. It is.
1. A 20% by mass para-toluenesulfonic 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 (I) is obtained by subtracting the amount of paratoluenesulfonic acid. By dividing the mass of the obtained adduct (I) by the weight of the cement admixture used in 1, the solid content ratio of the adduct (I) 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, if it is the cement admixture of the above form (1), a polyalkyleneimine alkylene oxide adduct (I) essentially comprising an oxyalkylene group having 3 or more carbon atoms, A cement admixture comprising the polycarboxylic acid polymer (A) will be produced. Also, in the case of the cement admixture of the above forms (2) and (3), an oxyalkylene group having 3 or more carbon atoms is added. A cement admixture comprising the essential polyalkyleneimine alkylene oxide adduct (I) will be produced, and the production method thereof is not particularly limited. For example, the polymer (A), the polymer (B) and / or the polymer (C) and the adduct (I) and / or the adduct (II) are prepared and mixed, respectively. Is preferred. The polymerization method and the like are as described later.

Hereinafter, the adduct (I), the adduct (II), the adduct (III), the polymer (A), the polymer (B), the polymer (C), and the polymer (D) in the present invention will be further described. To do.
The polyalkyleneimine alkylene oxide adduct (I) (adduct (I)) essentially comprising an oxyalkylene group having 3 or more carbon atoms may be any polyalkyleneimine having an oxyalkylene group having 3 or more carbon atoms. , May or may not have a polymerizable unsaturated double bond. These may be used in combination.
As the adduct (I) having a polymerizable unsaturated double bond, among the polyalkyleneimine alkylene oxide adduct monomers (c) described later, a polyalkylene having an essential oxyalkylene group having 3 or more carbon atoms. An imine alkylene oxide adduct is preferred.
As the adduct (I) 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 (I). 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 oxyalkylene group may be at least one oxyalkylene group having 3 or more carbon atoms. When two or more oxyalkylene groups are present in the same adduct, the oxyalkylene group may take any form such as random addition, block addition, alternating addition, etc. More preferred. The structure of the adduct (I) essentially including such an oxyalkylene group may be any structure obtained by adding at least one oxyalkylene group having 3 or more carbon atoms, such as ethylene oxide, propylene oxide, In addition to alkylene oxides having 2 to 8 carbon atoms such as butylene oxide, isobutylene oxide, 1-butene oxide, 2-butene oxide, trimethylethylene oxide, tetramethylene oxide, tetramethylethylene oxide, butadiene monooxide, and octylene oxide, dipentane ethylene oxide Aliphatic epoxides such as dihexane ethylene oxide; Alicyclic epoxides such as trimethylene oxide, tetramethylene oxide, tetrahydrofuran, tetrahydropyran, octylene oxide; styrene oxide, 1,1- It is preferable that a structure formed by one or more aromatic epoxides such as phenyl 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 water reducing property, slump retention, strength up effect, and air volume of the cement composition This is a preferable combination with a good balance of reduction effects.

With regard to the oxyalkylene group, a preferred form of the adduct (I) is a form obtained by adding two or more oxyalkylene groups and adding these in a block form. That is, the adduct (I) has an oxyalkylene chain composed of two or more oxyalkylene groups, and the oxyalkylene chain has a so-called ABA type block copolymer structure. Is preferred. More preferably, in such a structure, A is an oxyethylene group and B is an oxyalkylene group having 3 or more carbon atoms. In such an A-B-A type structure, a highly hydrophobic oxyalkylene group having 3 or more carbon atoms (part represented by B) is present inside the highly hydrophilic oxyethylene chain (part represented by A). ) Exist, and due to this structure, it is excellent in water reduction and excellent in low viscosity. More preferably, in the above structure, A is an oxyethylene group and B 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 (I) being an oxyethylene group, and such a form is also a particularly preferred form of the adduct (II).

The adduct (I) 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 mainly composed of ethyleneimine, so that the hydrophilicity of the adduct (I) 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 (I), 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 (I) may not be sufficiently exhibited, and if it exceeds 300, the polymerizability of the adduct (I) 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 (I), the average addition mole number of the oxyalkylene group is preferably more than 0 and 300 or less. If it exceeds 300, the polymerizability of these monomers may decrease. More preferably, it is 270 or less, More preferably, it is 250, Especially preferably, it is 220 or less, Most preferably, it is 200 or less. Further, it is more preferably 0.5 or more, further preferably 1 or more, particularly preferably 3 or more, and most preferably 5 or more. When the average addition mole number of the oxyalkylene group in the adduct (I) 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 is not sufficiently exhibited.
The average number of added moles means the average value of the number of moles of the oxyalkylene group added in 1 mole of the group formed by the oxyalkylene group of the adduct (I), or the adduct (I This means the average value of the number of moles of the oxyalkylene group added to 1 mole of nitrogen atom having an active hydrogen atom contained in the polyalkyleneimine.

As a weight average molecular weight of the said adduct (I), it is preferable that it is 300 or more, and it is preferable that it is 100,000 or less. More preferably, it is 400 or more, More preferably, it is 500 or more, More preferably, it is 600 or more, Most preferably, it is 1000. More preferably, it is 50000 or less, More preferably, it is 30000 or less.

As a particularly preferred form of the adduct (I), as described above, it has a block copolymer structure of ABA type (A: oxyethylene group, B: oxypropylene group), and the adduct. Although the terminal of (I) is an oxyethylene group, for example, as the adduct (I), for example, ethylene oxide is first added to polyethyleneimine, followed by propylene oxide and ethylene oxide in this order. It is suitable that it is obtained by making it.
In such an adduct (I), the average polymerization number of alkyleneimine per polyethyleneimine chain used and the addition mole number of ethylene oxide or propylene oxide are as described above, but are particularly suitable. As for the form, the average number of polymerizations of alkyleneimine per polyethyleneimine chain used is 10 to 20, the number of moles of ethylene oxide added to polyethyleneimine is 1 to 15, and the propylene oxide added to ethylene oxide is The number of added moles is 1 to 10, and the number of added moles of terminal ethylene oxide is 5 to 20. Most preferably, it is the form which is 13-15, 3-10, 4-7, 10-17 in order, respectively.

As the adduct (II), a polyalkyleneimine alkylene oxide adduct having an oxyalkylene group having 3 or more carbon atoms whose end is specified as an oxyethylene group, ie, an oxyethylene group at least at one end There is no particular limitation as long as it is an adduct (I).
The adduct (III) is a polyalkyleneimine alkylene oxide adduct having an oxyalkylene group having 3 or more carbon atoms other than the adduct (II), that is, the addition having no oxyethylene group at the terminal. There is no particular limitation as long as it is the product (I).

The polycarboxylic acid polymer (A) is obtained by copolymerizing a monomer component essentially comprising a polyalkylene glycol unsaturated monomer (a) and an unsaturated carboxylic acid monomer (b). Is preferred. More preferably, it is obtained by copolymerizing a monomer component containing 1 to 99% by mass of a polyalkylene glycol unsaturated monomer (a) and 99 to 1% by mass of an unsaturated carboxylic acid monomer (b). More preferably, a monomer component containing 40 to 97% by mass of the polyalkylene glycol unsaturated monomer (a) and 60 to 3% by mass of the unsaturated carboxylic acid monomer (b) is used. Polymerized.

Examples of the polycarboxylic acid polymer (B) obtained by copolymerizing the polyalkyleneimine alkylene oxide adduct monomer include polyalkylene glycol unsaturated monomers (a) and unsaturated carboxylic acid monomers. Those obtained by copolymerizing the monomer component essentially comprising (b) and the polyalkyleneimine alkylene oxide adduct monomer (c) are preferred. More preferably, the polyalkylene glycol unsaturated monomer (a) 98 to 40% by mass, the unsaturated carboxylic 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.

As the polycarboxylic acid copolymer (C) having a polyalkylene glycol side chain which essentially contains an oxyalkylene group having 3 or more carbon atoms, “in the polyalkylene glycol unsaturated monomer (a), In particular, a monomer component containing a polyalkylene glycol unsaturated monomer (a) "and an" unsaturated carboxylic acid monomer (b) ", which essentially contains an oxyalkylene group having 3 or more carbon atoms. Those obtained by copolymerizing are preferred. More preferably, a monomer component containing the polyalkylene glycol unsaturated monomer (a) 1 to 99% by mass and the unsaturated carboxylic acid monomer (b) 99 to 1% by mass 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 carboxylic acid monomer (b) Are copolymerized.

Examples of the polycarboxylic acid polymer (D) other than the polymer (B) and the polymer (C) include “in the polyalkylene glycol unsaturated monomer (a), particularly from only an oxyethylene group”. The polyalkylene glycol unsaturated monomer (a) ”and“ unsaturated carboxylic acid monomer (b) ”are included, and“ polyalkyleneimine alkylene oxide adduct monomer (c) ”is included. Those obtained by copolymerizing a monomer component which is not present are preferable. More preferably, a monomer component containing the polyalkylene glycol unsaturated monomer (a) 1 to 99% by mass and the unsaturated carboxylic acid monomer (b) 99 to 1% by mass 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 carboxylic acid monomer (b) Are copolymerized.
In the following, the polyalkylene glycol unsaturated monomer (a), the unsaturated carboxylic acid monomer (b) and the polyalkyleneimine alkylene oxide adduct monomer (c) are respectively represented by the monomer (a). Also referred to as monomer (b) and monomer (c).

In the polymer (A) and the polymer (B), 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 (A), 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 (B), 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 (A), the polyalkylene glycol unsaturated monomer (a) may be any one having a polymerizable unsaturated group and a polyalkylene glycol chain. Alkylene glycol ester monomers and unsaturated alcohol polyalkylene glycol adducts are preferred.
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. Such an unsaturated alcohol polyalkylene glycol adduct is preferably a compound represented by the following general formula (1).

In the general formula (1), R ¹ , R ² and R ³ are the same or different and each represents a hydrogen atom or a methyl group. R ⁴ represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms. R ^a is the same or different and represents an alkylene group having 2 to 18 carbon atoms. m represents the average addition mole number of the oxyalkylene group represented by R ^a O, and is a number of 1 to 300. X represents a divalent alkylene group having 1 to 5 carbon atoms, or, when the group represented by R ¹ R ³ C═CR ² — is a vinyl group, a carbon atom bonded to X, oxygen Indicates that atoms are directly bonded to each other.
When two or more oxyalkylene groups represented by — (R ^a O) — in the general formula (1) are present in the same unsaturated alcohol polyalkylene glycol adduct, — (R ^a O) — The represented oxyalkylene group may be in any addition form such as random addition, block addition, and alternate addition.

The oxyalkylene group represented by R ^a O is an alkylene oxide adduct having 2 to 18 carbon atoms, and the structure of such an alkylene oxide adduct is ethylene oxide, propylene oxide, butylene oxide, isobutylene oxide, 1 -A structure formed by one or more alkylene oxides such as butene oxide and 2-butene oxide. 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 is the average number of moles of the oxyalkylene group represented by R ^{a O} is the number of 1 to 300. When m exceeds 300, the polymerizability of the monomer is lowered. The preferable range of m is 2 or more, and the average added mole number of the oxyethylene group in — (R ^a 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 ⁴ 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 ⁴ 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 preferable. 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, A hydrocarbon group of 20 or less is preferable. More preferably, it is a C5-C10 hydrocarbon group. Of the hydrocarbon groups, a saturated alkyl group and an unsaturated alkyl group are preferable. 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 (2).

In the general formula (2), R ⁵ 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 ⁶ 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)-in the general formula (2) is the same as that in the general formula (1). 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 (2), 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 ⁶ has more than 30 carbon atoms, the polycarboxylic acid polymer is too hydrophobic, so that good dispersibility cannot be obtained. A preferred form of R ⁶ 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 preferable. 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, A hydrocarbon group of 20 or less is preferable. More preferably, it is a C5-C10 hydrocarbon group. Of the hydrocarbon groups, a saturated alkyl group and an unsaturated alkyl group are preferable. 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. In any of the saturated alcohols, an alkyl having 2 to 18 carbon atoms 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) (C2-C4 alkylene glycol) (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, ethoxypolyethyleneglycol mono (meth) acrylate, ethoxy {polyethyleneglycol (poly) propyleneglycol} mono (meth) acrylate, ethoxy {polyethyleneglycol (poly) butyleneglycol} mono (meta ) Acrylate, ethoxy {polyethylene glycol (poly) propylene glycol (poly) butylene glycol} mono (Meth) acrylate, propoxy polyethylene glycol mono (meth) acrylate, propoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, propoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, propoxy {polyethylene glycol ( Poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate.
Butoxy polyethylene glycol mono (meth) acrylate, butoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, butoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, butoxy {polyethylene glycol (poly) propylene glycol (Poly) butylene glycol} mono (meth) acrylate, pentoxypolyethylene glycol mono (meth) acrylate, pentoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, pentoxy {polyethylene glycol (poly) butylene glycol} mono ( Meth) acrylate, pentoxy {polyethylene glycol (poly) propylene glycol (poly) butylene glycol } Mono (meth) acrylate, hexoxypolyethylene glycol mono (meth) acrylate, hexoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, hexoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, hexoxy {Polyethylene glycol (poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate.

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

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 (2). 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 (A), the unsaturated carboxylic acid monomer (b) may be a monomer having a polymerizable unsaturated group and a group capable of forming a carbanion. However, unsaturated monocarboxylic acid monomers and unsaturated dicarboxylic acid monomers are preferred.
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. Preferred forms include the following general formula ( It is a compound represented by 3).

In the general formula (3), R ⁷ represents a hydrogen atom or a methyl group. M represents a hydrogen atom, a metal atom, an ammonium group or an organic amine group.
As a metal atom in M of the general formula (3), 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; Trivalent metal atoms such as aluminum and iron are 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 unsaturated dicarboxylic acid monomer may be any monomer having one unsaturated group and two groups capable of forming a carbanion in the molecule, but maleic acid, itaconic acid, citraconic acid , Fumaric acid and the like, monovalent metal salts, divalent metal salts, ammonium salts and organic amine salts thereof, or anhydrides thereof are suitable.
In addition to these, the unsaturated carboxylic acid monomer (b) is a half ester of an unsaturated dicarboxylic acid monomer and an alcohol having 1 to 22 carbon atoms, an unsaturated dicarboxylic acid and a carbon number. Preference is given to half amides with 1 to 22 amines, half esters of unsaturated dicarboxylic acid monomers and glycols having 2 to 4 carbon atoms, and half amides of maleamic acid and glycols having 2 to 4 carbon atoms.

In the monomer component forming the polymer (A), 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 carboxylic acids such as (meth) acrylic acid, maleic acid, fumaric acid, and citraconic acid; unsaturated carboxylic acid anhydrides such as (meth) acrylic anhydride and maleic anhydride; ) Unsaturated carboxylic acid halides such as acrylic acid chlorides; such as (meth) acrylic acid alkyl esters having 1 to 30 carbon atoms, maleic acid monoesters having 1 to 30 carbon atoms, maleic acid diesters having 1 to 30 carbon atoms, etc. Saturated carboxylic acid esters; epoxy compounds such as glycidyl (meth) acrylate and (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. A reaction formula for adding a polyethyleneimine ethylene oxide adduct and then performing a transesterification reaction with methacrylic acid is shown below. 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, polyalkyleneimine alkyleneoxide An adduct monomer (c) can be obtained.

In the above reaction formula, R ^a represents an initiator, EO represents ethylene oxide, - (EO) n-H is that the ethylene oxide n number to nitrogen atom having active hydrogen atoms in the polyethyleneimine is added MAA represents methacrylic acid. The symbol “...” In the chemical formula represents that the polymer chain continues in the same manner.
The polyalkyleneimine alkylene oxide adduct monomer (c) has a polyalkyleneimine chain, and such a polyalkyleneimine chain and preferred forms thereof are the same as described above. Further, the average number of polymerizations of alkyleneimine per polyalkyleneimine chain and its preferred form are also the same as described above.

The polycarboxylic acid polymer in the present invention, that is, the polycarboxylic acid polymer (A) or the polycarboxylic acid polymer (B) formed by copolymerizing the polyalkyleneimine alkylene oxide adduct monomer is formed. The monomer component may further contain another monomer (d) other than the monomers (a), (b) and (c) as necessary. 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.
Diesters of unsaturated dicarboxylic acid monomers and alcohols having 1 to 22 carbon atoms, diamides of unsaturated dicarboxylic acids and amines having 1 to 22 carbon atoms, unsaturated dicarboxylic acid monomers and carbon Diesters with glycols of 2-4.

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. .

Next, in the method for producing a polycarboxylic acid polymer in the present invention, a method for copolymerizing monomer components 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, Mole 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 copolymerization method, a chain transfer agent can also be used as necessary. As such a chain transfer agent, one or more commonly used ones can be used, but a hydrophobic chain transfer agent can also be used.
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.
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.

The hydrophobic chain transfer agent may be used in combination with one or two hydrophilic chain transfer agents as necessary. As such a hydrophilic chain transfer agent, those usually used can be used, and mercaptoethanol, thioglycerol, thioglycolic acid, mercaptopropionic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thiomalic acid. Thiol chain transfer agents such as 2-mercaptoethanesulfonic acid; primary alcohols such as 2-aminopropan-1-ol; secondary alcohols such as isopropanol; phosphorous acid, hypophosphorous acid and salts thereof (hypochlorous acid) Sodium phosphate, potassium hypophosphite, etc.) and sulfurous acid, hydrogen sulfite, dithionic acid, metabisulfite and its salts (sodium sulfite, sodium bisulfite, sodium dithionite, sodium metabisulfite, potassium sulfite, Potassium hydrogen sulfite, potassium dithionite, metabisulfite Lower oxides and salts thereof Um, etc.) is preferable.
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. Method of performing polymerization; charging a part of the monomer component into the reaction vessel, and adding the polymerization initiator and the remaining monomer component into the reaction vessel; copolymerizing; charging the reaction vessel with the polymerization solvent A method of adding the whole amount of the monomer and the polymerization initiator is 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 perform copolymerization by a method in which an agent and a monomer are successively dropped into a 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 carboxylic acid-type monomer (b) 0-60 mol%. The neutralization rate of the unsaturated carboxylic acid monomer (b) is the unsaturated carboxylic acid forming a salt when the total number of moles of the unsaturated carboxylic acid monomer (b) is 100 mol%. It is represented by mol% of the system monomer (b). When the neutralization rate of the unsaturated carboxylic acid monomer (b) exceeds 60 mol%, the polymerization rate in the copolymerization step does not increase, and the molecular weight of the resulting polymer decreases or the production efficiency decreases. There is a fear. 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 0 to 60 mol% of the unsaturated carboxylic acid monomer (b), the unsaturated carboxylic acid monomer (b), which is all acid type, that is, all In the unsaturated carboxylic acid monomer (b), a method in which M in the above general formula (3) is a hydrogen atom is subjected to copolymerization without neutralization, or unsaturated carboxylic acid monomer A method is preferred in which the body (b) is neutralized into a salt form such as a sodium salt or an ammonium salt using an alkaline substance and subjected to copolymerization with a neutralization rate of 0 to 60 mol%. is there.

As described above, the polycarboxylic acid polymer (B) obtained by copolymerizing the polycarboxylic acid polymer (A) 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 is a value measured under the following GPC measurement conditions.

(GPC molecular weight measurement conditions)
Column used: TSK guard column SWXL + TSKge1 G4000SWXL + G3000SWXL + G2000SWXL manufactured by Tosoh Corporation
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 3.21

The method for producing the cement admixture of the present invention includes the above-mentioned polyalkylene glycol unsaturated monomer (a), unsaturated carboxylic acid monomer (b), and polyalkyleneimine alkylene oxide adduct monomer. It can carry out by copolymerizing the monomer component which has (c) essential, and the cement admixture of the form of said (1)-(3) can be obtained. As the copolymerization method, the above-described method is suitable. However, when the cement admixture of the above form (1) is produced, the adduct (I) and the polycarboxylic acid polymer (A) are included. In addition, when the cement admixture of the above forms (2) and (3) is produced, the kind of monomer in the monomer component is included so that the adduct (I) is included. The amount, the copolymerization conditions, and the like are appropriately set.

The cement admixture of the present invention comprises an adduct (I) and a polycarboxylic acid polymer (A) as essential components, or an adduct (II) whose terminal is specified as an oxyethylene group as an essential component. To do. 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 (I) and the polycarboxylic acid polymer (A) 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. As the blending amount and unit water amount per 1 m ³ of concrete of the cement, for example, in order to produce highly durable and high strength concrete, the unit water amount is 100 to 185 kg / m ³ , and the water / cement ratio is 10 to 70. % Is preferable. 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 (I) and the polycarboxylic acid polymer (A) or the adduct (II) has a total cement mass of 100% by mass. Is preferably 0.01% by mass or more, and more preferably 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.
Lignin sulfonate; polyol derivative; naphthalene sulfonic acid formalin condensate; melamine sulfonic acid formalin condensate; polystyrene sulfonate; aminoaryl sulfonic acid-phenol-formaldehyde condensate as described in JP-A-1-113419, etc. Aminosulfonic acid type; as described in JP-A-7-267705, as a component (a), a copolymer of a polyalkylene glycol mono (meth) acrylic acid ester compound and a (meth) acrylic acid compound and / or A salt thereof, and as a component (b), a copolymer of a polyalkylene glycol mono (meth) allyl ether compound and maleic anhydride and / or a hydrolyzate thereof, and / or a salt thereof, and a component (c) As polyalkylene glycol mono (meth) allylamine A cement dispersant containing a copolymer of a polyalkylene glycol and a maleic ester of a polyalkylene glycol compound and / or a salt thereof; (meth) acrylic acid as component A as described in Japanese Patent No. 2508113 A copolymer of a polyalkylene glycol ester of (meth) acrylic acid (salt), a specific polyethylene glycol polypropylene glycol compound as the B component, and a concrete admixture comprising a specific surfactant as the C component; (Meth) acrylic acid polyethylene (propylene) glycol ester or polyethylene (propylene) glycol mono (meth) allyl ether, (meth) allyl sulfonic acid (salt), and (meth) as described in JP-A-62-216950 A copolymer comprising 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 ( Copolymers consisting of (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, ethylene oxide or the like is added to a specific unsaturated alcohol such as 3-methyl-3-buten-1-ol. Added alkenyl ether monomers, unsaturated carboxylic acid monomers, copolymers consisting of monomers copolymerizable with these monomers, or polycarboxylic acids (salts) such as salts thereof ). 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, alkenyl sulfosuccinic acid, α-olefin sulfonate, and the like.

(16) Other surfactants: aliphatic monohydric alcohols having 6 to 30 carbon atoms in the molecule such as octadecyl alcohol and stearyl alcohol, and those having 6 to 30 carbon atoms in the molecule such as abiethyl alcohol Intramolecular such as alicyclic monohydric alcohol, dodecyl mercaptan, etc. Intramolecular such as monovalent mercaptan having 6-30 carbon atoms in the molecule, such as nonylphenol, alkylphenol having 6-30 carbon atoms in the molecule, dodecylamine, etc. 10 mol or more of an alkylene oxide such as ethylene oxide or propylene oxide was added to a carboxylic acid having 6 to 30 carbon atoms in the molecule such as an amine having 6 to 30 carbon atoms, lauric acid or stearic acid. Polyalkylene oxide derivatives; having an alkyl group or alkoxyl group as a substituent Alkyl diphenyl ether sulfonates in which two phenyl groups having a sulfone group are ether-bonded; various anionic surfactants; various cationic surfactants such as alkylamine acetate and alkyltrimethylammonium chloride; various nonions Surfactants; various amphoteric surfactants.
(17) Waterproofing agent: fatty acid (salt), fatty acid ester, oil and fat, silicon, paraffin, asphalt, wax and the like.
(18) Rust preventive: 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, rust inhibitors, colorants, Examples thereof include fungicides, 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-mentioned 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 of the cement composition, foam suppression, and the like.
As a method for adding the cement additive or the cement dispersant to the cement composition, it is preferable to mix these cement additives or the cement dispersant to make a cement admixture and to easily mix the cement additive or cement dispersant into the cement composition. .

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. Viscosity that makes it easier to work on site can be achieved, not only to improve the state of the cement composition, etc., but also to reduce the amount of air in the cement composition and to increase the compressive strength of the hardened cement composition It can be raised.

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by weight” and “%” means “% by mass”.
In addition, as a weight average molecular weight, it carried out on the GPC molecular weight measurement conditions mentioned above.

Production Example 1
In a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer, 46.5 g of a commercially available polyethyleneimine (number average molecular weight 600; ethyleneimine addition number 14) and 0.1 g of sodium hydride were placed, and ethylene was heated at a temperature of 130 to 170 ° C. 953.5 g of oxide (addition number 20 mol with respect to polyethyleneimine active hydrogen) was added to obtain a polyalkyleneimine alkylene oxide compound. This compound was designated as P14-20-00-00 (does not contain propylene oxide).

Production Example 5
A pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer was charged with 37.2 g of commercially available polyethyleneimine (number average molecular weight 600; ethylene imine addition number 14) and 0.1 g of sodium hydride. 761.8 g of oxide (addition number 20 mol with respect to polyethyleneimine active hydrogen) was added, and then 200.8 g of propylene oxide (addition number 4 mol with respect to polyethyleneimine active hydrogen) was added, and polyalkyleneimine alkylene was added. An oxide compound was obtained. This compound was designated as P14-20-04-00 (containing 20.9% by mass of propylene oxide with respect to 100% by mass of alkylene oxide). The alkylene oxide in this case is the total mass of ethylene oxide and propylene oxide.

Production Example 9
A pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer was charged with 37.2 g of commercially available polyethyleneimine (number average molecular weight 600; ethylene imine addition number 14) and 0.1 g of sodium hydride. 380.9 g of oxide (addition number 10 mol with respect to polyethylenimine active hydrogen) was added, and then 301.3 g of propylene oxide (addition number 6 mol with respect to polyethylenimine active hydrogen) was added. A compound was obtained. This compound was designated as P14-10-06-00. Subsequently, 380.9 g of ethylene oxide (addition number of 10 mol with respect to polyethyleneimine active hydrogen) was added to obtain a polyalkyleneimine alkylene oxide compound. This compound was designated as P14-10-06-10 (containing 28.3% by mass of propylene oxide with respect to 100% by mass of alkylene oxide).

Production Example 14
In the same manner as in Production Example 9, 19.4 g of commercially available triethylenetetramine (number average molecular weight 146; ethyleneimine addition number 3) was placed in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer at a temperature of 130 to 170 ° C. 351.3 g of ethylene oxide (addition number 10 mol with respect to polyethyleneimine active hydrogen) was added, and then 277.9 g of propylene oxide (addition number 6 mol with respect to polyethyleneimine active hydrogen) was added, and polyalkyleneimine was added. An alkylene oxide adduct was obtained. This compound was designated as P03-10-06-00. Subsequently, 351.3 g of ethylene oxide (addition number of 10 mol with respect to polyethyleneimine active hydrogen) was added to obtain a polyalkyleneimine alkylene oxide adduct. This compound was designated as P03-10-06-10 (containing 28.3% by mass of propylene oxide with respect to 100% by mass of alkylene oxide).

Production Example 15
In the same manner as in Production Example 9, 33.8 g of commercially available polyethyleneimine (number average molecular weight 1800; ethyleneimine addition number 42) and 0.1 g of sodium hydride were placed in a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer. Then, 346.2 g of ethylene oxide (addition number 10 mol with respect to polyethyleneimine active hydrogen) was added at a temperature of 130 to 170 ° C., followed by 279.3 g of propylene oxide (addition number 6 mol with respect to polyethyleneimine active hydrogen). ) To obtain a polyoxyalkylene compound. This compound was designated as P42-10-06-00. Subsequently, 346.2 g of ethylene oxide (addition number of 10 mol with respect to polyethyleneimine active hydrogen) was added to obtain a polyalkyleneimine alkylene oxide adduct. This compound was designated as P42-10-06-10 (28.3% by mass of propylene oxide with respect to 100% by mass of alkylene oxide).

Production Examples 2-4, 6-8, 10-13, 16-25
Except for the average addition number of ethyleneimine and alkylene oxide as shown in Table 1, Production Examples 2 and 3 are the same as Production Example 1, Production Examples 4 and 6 are the same as Production Example 5, and Production Examples About 7, 8, 10-13, and 16-25, it carried out similarly to manufacture example 9, and obtained the polyalkylene imine alkylene oxide addition product 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 26
(Manufacture of “Monomer 1”)
600 g of a polyethyleneimine ethylene oxide adduct (a compound obtained by adding 3 mol of ethylene oxide average addition mole to active hydrogen of polyethyleneimine of Mw 600) in a glass reactor equipped with a thermometer, a stirrer, a dropping device, an air introduction tube and a reflux cooling device, Metoquinone 0.12 g and acetic acid 18.5 g were charged and maintained at 90 to 95 ° C. for 30 minutes. Thereafter, 47.4 g of glycidyl methacrylate was dropped into the reaction vessel over 60 minutes while maintaining 90 to 95 ° C. Thereafter, the temperature was maintained at 90 to 95 ° C. for 1 hour, and then the temperature was lowered to 65 ° C., and 990 g of water and 79 g of methacrylic acid were added to adjust pH to 7.0 to synthesize “Monomer 1”.

(Manufacture of polymer)
A glass reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen introduction tube and a reflux cooling device was charged with 1100 g of water, and the inside of the reactor was purged with nitrogen under stirring, and heated to 70 ° C. in a nitrogen atmosphere. Methoxypoly (n = 4) ethylene glycol monomethacrylate 1286g, methacrylic acid 192g, water 193g and 3-mercaptopropionic acid 66g as a chain transfer agent mixed with monomer aqueous solution and 1013g of "monomer 1" for 4 hours, 352 g of 8% ammonium persulfate aqueous solution was dropped into the reaction vessel over 5 hours. Thereafter, the temperature was maintained at 70 ° C. to complete the polymerization reaction. After cooling, the solution was neutralized to pH 7.0 with an aqueous sodium hydroxide solution to obtain an aqueous solution of polymer 1 having a weight average molecular weight of 9000.

Production Example 27
597 g of water was charged into a glass reactor equipped with a thermometer, a stirrer, a dropping device, a nitrogen inlet tube and a reflux cooling device, and the inside of the reactor was purged with nitrogen under stirring and heated to 75 ° C. under a nitrogen atmosphere. A reaction vessel containing 633 g of methoxypoly (n = 6) ethylene glycol monomethacrylate, 167 g of methacrylic acid, 9 g of 3-mercaptopropionic acid, and 166 g of water for 5 hours, and 84 g of 11.1% ammonium persulfate aqueous solution for 6 hours. It was dripped in. Thereafter, the temperature was maintained at 75 ° C. to complete the polymerization reaction. After cooling, the solution was neutralized with an aqueous sodium hydroxide solution to pH 7.0 to obtain an aqueous solution of polymer 2 having a weight average molecular weight of 15000.

Production Example 28
In a reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen introduction tank, and a cooling tank, 144 g of water was charged and the temperature was raised to 60 ° C. Subsequently, 17 g of molten maleic acid and 196 g of IPN-50 (isoprenol ethylene oxide 50 mol adduct) were added, and the temperature was adjusted to 60 ° C. After mixing 0.5 g of 30% hydrogen peroxide water, a solution in which 11.2 g of water and 0.24 g of L-ascorbic acid were mixed was added dropwise over 1 hour. Then, it stirred for 1 hour, keeping at 60 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 3 having a weight average molecular weight of 28000.

Production Example 29
_{(H- (OC 2 H 4)} 13 - (OC 3 H 6) 2 - (OC 2 H 4) preparation of 10 -OCH ₃₎
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 introduction tank, and a nitrogen introduction 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, after which the inside of the reactor was again purged with nitrogen, and 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 of “Esterified aqueous solution 1”)
In a reactor equipped with a thermometer, a stirrer, a nitrogen inlet, and a condensed water separator, 2083 g of the above polyalkylene glycol monomethyl ether, 350 g of methacrylic acid, 54 g of paratoluenesulfonic acid monohydrate, 0.5 g of phenothiazine, and 243 g of cyclohexane was charged as an azeotropic solvent, and condensed water was separated while maintaining at 115 ° C. 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 “esterified aqueous solution 1” containing 72% of an esterified product and 8% of unreacted methacrylic acid.

(Manufacture of polymer)
A reactor equipped with a thermometer, a stirrer, a dropping device, a nitrogen introducing tank, and a cooling tank was charged with 50 g of distilled water and heated to 80 ° C. Subsequently, 200 g of the above “esterified aqueous solution 1”, 25 g of methacrylic acid, 71 g of distilled water, and 3.5 g of 3-mercaptopropionic acid were mixed for 4 hours, and 47.9 g of distilled water and 2.1 g of ammonium persulfate were added. The mixed solution was added dropwise over 5 hours. Thereafter, the mixture was stirred for 1 hour while maintaining at 80 ° C. to complete the polymerization. After cooling, an aqueous sodium hydroxide solution was added to adjust the pH to 7 to obtain an aqueous solution of polymer 4 having a weight average molecular weight of 14,000.

Production Example 30
115 g of distilled water was charged into a reactor equipped with a thermometer, a stirrer, a dropping device, a nitrogen introduction tank, and a cooling tank, and the temperature was raised to 80 ° C. _{Subsequently, (H- (OC 2 H 4} ) 7 - (OC 3 H 6) 2 - (OC 2 H 4) 6 -OCH 3 methacrylic acid ester 273 g, 11.4 g of methacrylic acid, water 11.2 g, and A solution in which 3.5 g of 3-mercaptopropionic acid was mixed for 4 hours, “a solution in which 48.6 g of water and 1.4 g of a 30% aqueous hydrogen peroxide solution were mixed”, “49.5 g of distilled water and L-ascorbic acid 0 Each solution was added dropwise over 5 hours, and then stirred for 1 hour while maintaining at 80 ° C. to complete the polymerization.After cooling, an aqueous sodium hydroxide solution was added to adjust the pH to 7, An aqueous solution of a polymer with a weight average molecular weight of 13000 was obtained.

Production Example 31
The monomer composition ratio was changed as shown below, and the amount of mercaptopropionic acid was adjusted so as to be the weight average molecular weight of each polymer.
Polymer 6: IPN50 / AANa = 85/15 (mass%), weight average molecular weight 30000
Polymer 7: IPN50 / AANa / HEA = 87.5 / 10 / 7.5 (mass%), weight average molecular weight 30000
Polymer 8: IPN50 / AANA = 97.5 / 7.5 (mass%), weight average molecular weight 30000
Polymer 9: PGM10 / MAANA = 75/25 (mass%), weight average molecular weight 17000
Polymer 10: PGM10 / MAANA / MMA = 67/8/25 (mass%), weight average molecular weight 12000
Polymer 11: PGM25 / MAANAa = 87.5 / 12.5 (mass%), weight average molecular weight 20000
IPN50: ethylene oxide 50 mol adduct of isoprenol HEA: hydroxyethyl acrylate AANAa: sodium acrylate MMA: methyl methacrylate PGM10: methoxypoly (n = 10) ethylene glycol monomethacrylate PGM25: methoxypoly (n = 25) ethylene glycol monomethacrylate

Examples 1-17 and Comparative Examples 1-17
The ratio which shows the polyalkyleneimine alkylene oxide adduct of manufacture examples 1-25 and the copolymer (polymer) 1-11 of manufacture examples 26-31 to the mixing | blending tables 1-3 (Tables 2, 4, 6). And evaluated by the following concrete test method. The results are shown in Performance Evaluation Tables 1 to 3 (Tables 3, 5, and 6).
In addition, in following Tables 1-6, the addition amount represents the solid content mass% of the admixture with respect to the cement mass, and the blending ratio of the admixture represents the solid content mass ratio. The admixture is a mixture of adducts A and B and polymers A, B, and C at a blending ratio in the blending table.

[Concrete test method]
The concrete composition was as follows.
Water: 175kg / m3
Cement (manufactured by Taiheiyo Cement, Sumitomo Osaka Cement, Ube Mitsubishi Cement: ordinary Portland cement): 389 kg / m3
Fine aggregate (Kimitsu mountain sand): 831kg / m3
Coarse aggregate (Hachinohe limestone): 924kg / m3
W / C: 45% s / a: 47.7%
In the above composition, the cement admixture was mixed in advance with kneading water, 30 L of concrete material was put into a 55 L biaxial kneading mixer, and kneaded for 120 seconds.
The measurement of the slump flow value and the amount of air of the obtained concrete was performed according to Japanese Industrial Standards (JIS A1101 (1998), 1128 (1999), 6204 (2000)).

From the above Tables 1 to 6, the state of concrete using an admixture in which “a compound obtained by adding ethylene oxide and propylene oxide to all active hydrogens of polyethyleneimine” and “polycarboxylic acid polymer” are both viscous. Was low, moist and in good condition. In addition, in the concrete blending, it is possible to adjust the air amount with the AE agent without using an antifoaming agent that is essential for an admixture made of a polycarboxylic acid polymer. Furthermore, the compressive strength of the hardened concrete was also high. On the other hand, the admixture which does not use “a compound obtained by adding ethylene oxide and propylene oxide to all active hydrogens of polyethyleneimine” had a high viscosity, stickiness and poor response.

Examples 18 to 36 and Comparative Examples 18 to 19
The following concretes are prepared by mixing the polyalkyleneimine alkylene oxide adducts of Production Examples 1 to 25 and the copolymers 1 to 11 of Production Examples 26 to 31 in the proportions shown in Formulation Table 4 (Table 7). The test method was used for evaluation. The results are shown in Performance Evaluation Table 4 (Table 7).
In addition, in the following Table 7, the addition amount represents the solid content mass% of the admixture with respect to the cement mass, and the blending ratio of the admixture represents the solid content mass ratio. The admixture is a mixture of adducts A and B and polymers A, B, and C at a blending ratio in the blending table. Moreover, all the Examples and Comparative Examples in Table 7 used 0.21% of cement admixture. Further, as the antifoaming agent, 0.01% of cement weight was used by adjusting “Micro Air 404 (trade name)” manufactured by NM Co. to a 1% aqueous solution.

[Concrete test method]
The concrete composition was as follows.
Water: 175 kg / m ³
Cement (Sumitomo Osaka Cement): 389kg / m ³
Fine aggregate (Kimitsu mountain sand): 831kg / m ³
Coarse aggregate (Hachinohe limestone): 924kg / m ³
W / C: 45% s / a: 47.7%
In the above composition, the cement admixture was mixed in advance with kneading water, 30 L of concrete material was put into a 55 L biaxial kneading mixer, and kneaded for 120 seconds.
The slump flow value of the obtained concrete, the measurement of the amount of air, and the measurement of the compressive strength of the hardened concrete were performed according to Japanese Industrial Standards (JIS A1101 (1998), 1128 (1999), 6204 (2000)).

Claims (11)

A cement admixture comprising a polyalkyleneimine alkylene oxide adduct (I) essentially comprising an oxyalkylene group having 3 or more carbon atoms and a polycarboxylic acid polymer (A),
The cement admixture contains the polyalkyleneimine alkylene oxide adduct (I) in an amount of 1% by mass to 30% by mass with respect to 100% by mass of the solid content of the cement admixture .
In the polyalkyleneimine alkylene oxide adduct (I), the content of oxyalkylene groups having 3 or more carbon atoms is 50% by mass or less with respect to 100% by mass of the total amount of oxyalkylene groups of the adduct (I). cement admixture, characterized in that there <br/>. The cement admixture according to claim 1, wherein the end of the polyalkyleneimine alkylene oxide adduct (I) is an oxyethylene group. The polyalkyleneimine alkylene oxide adduct (I) contains 1% by mass or more of an oxyalkylene group having 3 or more carbon atoms with respect to 100% by mass of the total amount of oxyalkylene groups. The cement admixture described in 1. The polyalkyleneimine alkylene oxide adduct (I) are, according to claim 3, wherein the total amount 100% by weight of the oxyalkylene group, in that it contains 3 or more oxyalkylene group having a carbon or 15 wt% Cement admixture. The cement admixture according to any one of claims 1 to 4 , wherein the oxyalkylene group having 3 or more carbon atoms is an oxypropylene group. The polycarboxylic acid polymer (A) is obtained by copolymerizing a monomer component essentially comprising a polyalkylene glycol unsaturated monomer (a) and an unsaturated carboxylic acid monomer (b). The cement admixture according to any one of claims 1 to 5, which is a polymer. The polycarboxylic acid polymer (A) comprises a polyalkylene glycol unsaturated monomer (a), an unsaturated carboxylic acid monomer (b), and a polyalkyleneimine alkylene oxide adduct monomer (c). The cement admixture according to claim 6, comprising a polymer (B) obtained by copolymerizing a monomer component essential for. The polycarboxylic acid-based polymer (A) includes a polyalkylene glycol-based unsaturated monomer (a) and an unsaturated carboxylic acid-based monomer (b) containing an oxyalkylene group having 3 or more carbon atoms as an essential component. The cement admixture according to claim 6 or 7, comprising a polymer (C) obtained by copolymerizing a monomer component essentially comprising a). The polyalkyleneimine alkylene oxide adduct (I) has an oxyalkylene chain composed of two or more oxyalkylene groups,
The oxyalkylene chain has a block copolymer structure of ABA type (A represents an oxyethylene group. B represents an oxyalkylene group having 3 or more carbon atoms). Item 9. The cement admixture according to any one of Items 1 to 8 . In the polyalkyleneimine alkylene oxide adduct (I), the average number of polymerizations of alkyleneimine per polyalkyleneimine chain is 10 or more.
The cement admixture according to claim 9. In the polyalkyleneimine alkylene oxide adduct (I), the average number of polymerizations of alkyleneimine per polyalkyleneimine chain is 14 or more.
The cement admixture according to any one of claims 1 to 8, characterized in that.