JP2000007402A - Cement additive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a copolymer for an excellent cement additive exhibiting high water-reducing performance. SOLUTION: This copolymer (A) consists of a polyalkylene glycol 3-methyl-3- butenyl ether monomer (I) having a number average mol.wt. of 1,800 to <2,800 (expressed in terms of polyethylene glycol) by gel permeation chromatography, a maleic acid type monomer (II) and another monomer (III) copolymerizable with the monomers (I) and (II) and has a 65-90 mgKOH/g carboxylic acid value and a 18-26 mgKOH/g hydroxyl value. The copolymer (A) is used for a cement additive.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a cement additive.

[0002]

2. Description of the Related Art In the concrete industry in recent years, there is a strong demand for improvements in durability and strength of concrete buildings, and reduction of a unit water volume is an important issue. Therefore, there are many proposals for cement dispersants. For example, Japanese Patent Publication No. 58-3
No. 8380 discloses a method in which a polyethylene glycol monoallyl ether monomer (a), a maleic acid monomer (a), and a monomer copolymerizable with these monomers (c) are used at a specific ratio. Although a cement dispersant containing the copolymer as a main component has been proposed, the water reducing performance is not yet sufficient.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a cement additive having excellent water reducing performance.

[0004]

DISCLOSURE OF THE INVENTION As a result of the study, the present inventors have found that a specific copolymer (A) having a specific carboxylic acid value and a limited hydroxyl value using a monomer having a specific number average molecular weight is used. )
Was found to be an excellent cement additive exhibiting high water reducing performance, and the present invention was completed. That is, the present invention provides a cement additive exhibiting high water reducing performance.

The object of the present invention is to provide a polyalkylene glycol 3
-Methyl-3-butenyl ether having a number average molecular weight of 18
The hydroxyl value obtained by polymerizing a monomer component containing the monomer (I) in the range of from 00 to less than 2800 and the maleic acid monomer (II) is 18 to 26 mgKOH / g, and a carboxylic acid This is achieved by a cement additive characterized in that it comprises a copolymer (A) whose value ranges from 65 to 95 mg KOH / g.

The above objects are achieved by (1) alkoxypolyalkylene glycol 3-methyl-3-butenyl ether
[The alkoxy group is an alkyl group having 1 to 22 carbon atoms, a phenyl group or an alkylphenyl group (the alkyl group in the alkylphenyl group has 1 to 22 carbon atoms), and the glycol moiety is an oxyalkylene having 2 to 4 carbon atoms. Represents one or a mixture of two or more groups, and in the case of two or more groups, they may be added in block form or in random form.] And has a number average molecular weight of 1800 or more and less than 2800. 60 to 99% by weight of the monomer (I) and the general formula (1)

[0007]

Embedded image

(Wherein M ¹ and M ² each independently represent hydrogen, a monovalent metal, a divalent metal, ammonium or an organic amine, and X represents —OM ² or —Y— (R ¹ O) qR ² And Y represents -O- or -NH-, R1O represents ^one or a mixture of two or more oxyalkylene groups having 2 to 4 carbon atoms, and in the case of two or more, addition in the form of a block. R ² may be hydrogen, an alkyl group having 1 to 22 carbon atoms, a phenyl group, an aminoalkyl group, an alkylphenyl group, or a hydroxylalkyl group (aminoalkyl group, alkylphenyl group). , The alkyl group in the hydroxylalkyl group has 1 to 22 carbon atoms), and q is the average number of added moles of the oxyalkylene group, which is in the range of 0 to 300, provided that M ¹ is bonded. Oxygen and A maleic acid-based unit represented by the general formula (I) wherein the carbon bonded to is bonded to form an acid anhydride group (-CO-O-CO-). In this case, M1 and X do not exist.) The carboxylic acid value obtained by polymerizing 40 to 1% by weight of the monomer (II) and 0 to 49% by weight of the other copolymerizable monomer (III) is 65 to 95 mgKOH /
This is achieved by a cement additive characterized in that it comprises a copolymer (A) in the range of g.

Also, (2) polyalkylene glycol 3
-Methyl-3-butenyl ether (the glycol moiety represents one or a mixture of two or more oxyalkylene groups having 2 to 4 carbon atoms. To the monomer (IV) having a number average molecular weight of 1800 or more and less than 2800, and 60 to 99% by weight of the above-mentioned general formula (1).
(Wherein, M ¹ and M ² each independently represent hydrogen, a monovalent metal, a divalent metal, ammonium or an organic amine;
X represents -OM ² or ^{-Y- (R 1 O) qR 2} , Y is -
O- or -NH-; R1O represents ^one or a mixture of two or more oxyalkylene groups having 2 to 4 carbon atoms. R ² may be hydrogen, carbon number 1 to
22 represents an alkyl group, a phenyl group, an aminoalkyl group, an alkylphenyl group, or a hydroxylalkyl group (the alkyl group in the aminoalkyl group, the alkylphenyl group, and the hydroxylalkyl group has 1 to 22 carbon atoms); The average number of moles of the oxyalkylene group added,
It is in the range of 0-300. However, it includes those in which the oxygen to which M ¹ is bonded and the carbon to which X is bonded form an acid anhydride group (—CO—O—CO—). In this case, M1 and X do not exist. The carboxylic acid value obtained by polymerizing 40 to 1% by weight of the maleic acid monomer (II) and 0 to 49% by weight of the other copolymerizable monomer (III) is 65 to 65%. This is achieved by a cement additive characterized by containing a copolymer (A) having a hydroxyl value in the range of 95 mg KOH / g and a hydroxyl value in the range of 18 to 26 mg KOH / g.

(3) alkoxypolyalkylene glycol 3-methyl-3-butenyl ether [alkoxy group is an alkyl group having 1 to 22 carbon atoms, phenyl group or alkylphenyl group (the carbon number of the alkyl group in the alkylphenyl group is Wherein the glycol moiety represents one or a mixture of two or more oxyalkylene groups having 2 to 4 carbon atoms. May be added] and 60 to 99% by weight of the monomer (I) having a number average molecular weight in the range of 1800 or more and less than 2800, and the general formula (1) (wherein M ¹ and M ² are Each independently represents hydrogen, a monovalent metal, a divalent metal, ammonium or an organic amine;
Represents OM ² or ^{-Y- (R 1 O) qR 2} , Y represents -O- or -NH-, R ¹ O is one or a mixture of two or more oxyalkylene group having 2 to 4 carbon atoms In the case of two or more kinds, they may be added in block form or in random form, and R ² is hydrogen, alkyl group having 1 to 22 carbon atoms, phenyl group, aminoalkyl group, alkylphenyl Represents a group or a hydroxylalkyl group (the alkyl group in the aminoalkyl group, the alkylphenyl group and the hydroxylalkyl group has 1 to 22 carbon atoms), q is the average number of added moles of the oxyalkylene group, and 0 to 30.
It is in the range of 0. However, the oxygen to which M ¹ is bonded and X
Is bonded to the carbon to which it is bonded to form an acid anhydride group (—CO—
O-CO-). In this case M1
And X do not exist. The carboxylic acid value obtained by polymerizing 40 to 1% by weight of the maleic acid monomer (II) and 0 to 49% by weight of the other copolymerizable monomer (III) is 65 to 65%. The present invention is also achieved by a method for producing a cement additive, which comprises a copolymer (A) having a range of 95 mgKOH / g.

(4) polyalkylene glycol 3-methyl-3-butenyl ether (where the glycol moiety represents one or a mixture of two or more oxyalkylene groups having 2 to 4 carbon atoms, and In this case, it may be added in a block shape or in a random shape.)
And 60 to 99% by weight of the monomer (IV) having a number average molecular weight of 1800 or more and less than 2800, wherein M ¹ and M ² each independently represent hydrogen, monovalent metal, divalent metal, ammonium or organic amine, X represents -OM ² or ^{-Y- (R 1 O) qR 2} , Y
Represents —O— or —NH—, and R ¹ O has 2 to 4 carbon atoms.
Of represents an oxyalkylene one or a mixture of two or more groups, in the case of two or more also be added in a block form may also be added to the random form, R ² represents hydrogen, carbon 1
To 22 alkyl groups, phenyl groups, aminoalkyl groups,
Represents an alkylphenyl group or a hydroxylalkyl group (the alkyl group in the aminoalkyl group, the alkylphenyl group, and the hydroxylalkyl group has 1 to 22 carbon atoms); q is the average number of added moles of the oxyalkylene group; ３００300. However, it includes those in which the oxygen to which M ¹ is bonded and the carbon to which X is bonded form an acid anhydride group (—CO—O—CO—).
In this case, M1 and X do not exist. The carboxylic acid value obtained by polymerizing 40 to 1% by weight of the maleic acid monomer (II) and 0 to 49% by weight of the other copolymerizable monomer (III) is 65 to 65%. It is also achieved by a method for producing a cement additive, which comprises a copolymer (A) having a range of 95 mgKOH / g and a hydroxyl value of 18 to 26 mgKOH / g.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the polyalkylene glycol in the monomer (I) include polyethylene glycol, polypropylene glycol, polybutylene glycol, or a block or random copolymer composed of two or more of these. And one or more of these can be used. Among them, the alkylene glycol is preferably ethylene glycol, in which case the average addition mole number of ethylene oxide is 4
It is preferably from 0 to less than 60. Further, the terminal of the polyalkylene glycol may be a hydroxyl group (-OH) or an alkoxy group (-
OR ³ ). R ³ in the alkoxy group is not particularly limited, but is preferably an alkyl group having 1 to 22 carbon atoms, a phenyl group or an alkylphenyl group (the alkyl group in the alkylphenyl group has 1 to 22 carbon atoms).

In order to obtain high water reducing performance, the monomer (I)
It is important to disperse the cement particles due to steric repulsion and hydrophilicity caused by the polyalkylene glycol contained in the cement.
For this purpose, the monomer (I) preferably has a large number average molecular weight. On the other hand, since the copolymer must be adsorbed on the cement particles in order to obtain water reduction, the number average molecular weight of the copolymer is naturally limited. Therefore, the monomer (I) having a number average molecular weight of 1800 or more and less than 2800, preferably 2000 or more and less than 2400 in terms of polyethylene glycol by gel permeation chromatography (hereinafter referred to as “GPC”) is specific. It can be seen that the water reduction rate has improved.

The monomer (II) is represented by the general formula (1). Examples of such a monomer (II) include maleic acid, maleic anhydride, half esters of maleic acid and an alcohol having 1 to 22 carbon atoms; Half amides; half amides or half esters of maleic acid and amino alcohols having 1 to 22 carbon atoms; compounds (C) obtained by adding 1 to 300 moles of oxyalkylene having 2 to 4 carbon atoms to these alcohols, and maleic acid Half esters with an acid; half amides of a compound obtained by aminating a hydroxyl group at one end of the compound (C) with maleic acid; maleic acid and a glycol having 2 to 4 carbon atoms or an addition mole number of 2 of these glycols Half-ester with polyalkylene glycol of 100 to 100, maleamic acid and glycol of 2 to 4 carbon atoms or these glycols Number of moles added: 2 to 1
And half-amides thereof with polyalkylene glycols, and monovalent metal salts, divalent metal salts, ammonium salts and organic amine salts thereof.
Species or two or more can be used.

The monomer (III) is composed of the monomers (I) and / or
Or a monomer copolymerizable with the monomer (II). Examples of such a monomer (III) include unsaturated dicarboxylic acids such as fumaric acid, itaconic acid and citraconic acid, and monovalent metal salts, divalent metal salts and ammonium salts thereof.
Monoesters and diesters of organic amine salts and these acids with alkyl alcohols having 1 to 20 carbon atoms and glycols having 2 to 4 carbon atoms or polyalkylene glycols having an addition mole number of 2 to 100 of these glycols, One-terminal aminated products of these acids, alkylamines having 1 to 20 carbon atoms and glycols having 2 to 4 carbon atoms, or addition mole numbers of these glycols of 2 to 10
Monoamides and diamides with an aminated polyalkylene glycol at one terminal; maleic acid and 1 to 20 carbon atoms
Diesters of an alkyl alcohol and a glycol having 2 to 4 carbon atoms or a polyalkylene glycol having an addition mole number of 2 to 100 of these glycols; Diamides of one of the above-mentioned aminated amino acids of glycols or polyaminoalkylene glycols having one-terminal aminated compound having an addition mole number of 2 to 100;
Unsaturated carboxylic acids such as (meth) acrylic acid and the like, monovalent metal salts, divalent metal salts, ammonium salts, organic amine salts, these acids and alkyl alcohols having 1 to 20 carbon atoms and 2 to 4 carbon atoms. Glycols or esters of these glycols with polyalkylene glycols having an addition mole number of 2 to 100, or one-terminal aminated products of glycols having 2 to 4 carbon atoms, or polyalkylenes having an addition mole number of 2 to 100 of these glycols Amides of glycol with one terminal aminated product; unsaturated sulfonic acids such as sulfoethyl (meth) acrylate, 2-methylpropanesulfonic acid (meth) acrylamide, and styrenesulfonic acid; and monovalent metal salts and divalent metal salts thereof. , Ammonium salts and organic amine salts; (meth) acrylamide, (meth) Unsaturated amides such as acrylalkylamide; unsaturated amino compounds such as dimethylaminoethyl (meth) acrylate; vinyl esters such as vinyl acetate and vinyl propionate; and aromatic vinyls such as styrene. , One or more of these can be used.

In order to obtain the copolymer (A) of the present invention, the above monomer components may be copolymerized using a polymerization initiator.
Copolymerization can be performed by a known method such as solution polymerization or bulk polymerization.

The solution polymerization can be carried out batchwise or continuously, and the solvent used in this case is water; alcohols such as methyl alcohol, ethyl alcohol and isopropyl alcohol; benzene, toluene, xylene,
Aromatic or aliphatic hydrocarbons such as cyclohexane and n-hexane; ester compounds such as ethyl acetate; acetone;
Ketone compounds such as methyl ethyl ketone and the like can be mentioned, and at least one selected from the group consisting of water and lower alcohols having 1 to 4 carbon atoms is used from the solubility of the raw material monomers and the obtained copolymer. Among them, it is more preferable to use water as the solvent, because the solvent removing step can be omitted. When maleic anhydride is used for copolymerization,
Polymerization using an organic solvent is preferred.

In the case of aqueous solution polymerization, as a radical polymerization initiator, a persulfate such as ammonium persulfate, sodium persulfate or potassium persulfate; hydrogen peroxide; an azoamidine compound such as azobis-2-methylpropionamidine hydrochloride; A water-soluble polymerization initiator is used, in this case, an alkali metal sulfite such as sodium hydrogen sulfite,
F such as metabisulfite, sodium hypophosphite, Mohr salt, etc.
An accelerator such as e (II) salt, sodium hydroxymethanesulfinate dihydrate, hydroxylamine hydrochloride, thiourea can be used in combination.

For solution polymerization using a lower alcohol, an aromatic or aliphatic hydrocarbon, an ester compound or a ketone compound as a solvent, a peroxide such as benzoyl peroxide, lauroyl peroxide or sodium peroxide; Hydroperoxides such as peroxide and cumene hydroperoxide; azo compounds such as azobisisobutyronitrile; and the like are used as radical polymerization initiators. In this case, an accelerator such as an amine compound may be used in combination. Further, when a water-lower alcohol mixed solvent is used, it can be appropriately selected from the above various radical polymerization initiators or a combination of the radical polymerization initiator and the accelerator.

In the bulk polymerization, as a radical polymerization initiator, peroxides such as benzoyl peroxide, lauroyl peroxide and sodium peroxide; hydroperoxides such as t-butyl hydroperoxide and cumene hydroperoxide; azobisisobutyronitrile Using an azo compound or the like in a temperature range of 40 to 200 ° C.

In the various polymerizations described above, if necessary, mercaptoethanol, thioglycerol, thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thiomalic acid, octyl thioglycolate, 3-mercaptopropion Octyl acid 2-
One or more chain transfer agents such as mercaptoethanesulfonic acid can be used.

The copolymer (A) thus obtained
Is used as a main component of the cement dispersant as it is, but if necessary, the copolymer (A) may be further neutralized with an alkaline substance before use. Preferred examples of such an alkaline substance include inorganic salts such as hydroxides, chlorides and carbonates of monovalent and divalent metals; ammonia; and organic amines. When maleic anhydride is used for copolymerization, the obtained copolymer may be used as it is as a cement additive or may be used after being hydrolyzed.

The weight ratio of monomer (I) / monomer (II) / monomer (III) in copolymer (A) is (I) / (I
I) / (III) = 60-99 / 40-1 / 0-49,
Preferably (I) / (II) / (III) = 70-95
/ 30-5 / 0-30, more preferably (I) / (I
I) / (III) = 75-95 / 25-5 / 0-10. The carboxylic acid value of the copolymer (A) is 65 to 90 mgKOH / g, preferably 70 to 90 mgKOH / g.
mgKOH / g, more preferably 75-90 mgKOH
/ G. Further, the hydroxyl value of the copolymer (A) is 1
8 to 26 mgKOH / g, preferably 19 to 25 mgK
OH / g, more preferably 20 to 24 mg KOH / g,
It is. If the weight ratio and the carboxylic acid value are out of the range, a cement additive exhibiting high water reducing performance cannot be obtained.

In a cement composition containing at least cement, water and a cement additive, the cement additive of the present invention can be used as a cement additive.

The cement which is a component of the cement composition comprises:
Portland cement (ordinary, fast, super fast, moderate heat,
Sulfate resistant and low alkali type of each, various mixed cement (Blast furnace cement A, B, C class, silica cement A,
Class B / C, fly ash cement class A / B / C), special cement (white Portland cement, alumina cement, ultra-rapid hardening cement, cement for grout, oil well cement, low heat generating cement, cement solidified material, etc.), low heat generation Type cement (low heat type blast furnace cement, low heat type blast furnace cement + fly ash, high belite cement, two-component low heat type cement "Slag-Portland cement type",
Three-component low heat-generating cement "slag-fly ash-cement", ultra-rapid hardening cement (1 clinker-rapid-hardening cement, admixture-type rapid-hardening cement, magnesium phosphate cement), ultra-high-strength cement, rapid-hardening cement, etc. Hydraulic cement. There is no particular limitation on the unit water amount, cement usage amount and water / cement ratio per 1 m ^{3 of} concrete. The unit water amount is 185 kg / m ³ or less, the used cement amount is 270 to 800 kg, and the water / cement ratio = 1.
It can be used in a wide range from 5% to 70% poor blend to rich blend. Further, the cement additive of the present invention is also effective for mortar and concrete requiring high fluidity such as high fluidity concrete.

The cement additive of the present invention can be used in combination with a known cement dispersant. Known cement dispersants used in combination include, for example, lignin sulfonic acid salt; polyol derivative; naphthalene sulfonic acid formalin condensate; melamine sulfonic acid formalin condensate; polystyrene sulfonic acid salt; Aminosulfonic acids such as phenol-formaldehyde condensates;
267705, a copolymer of a polyalkylene glycol mono (meth) acrylate compound and a (meth) acrylic compound and / or a salt thereof as the component (a), and a polyalkylene glycol mono (meth) as the component (b) A) a copolymer of an allyl ether compound and maleic anhydride and / or a hydrolyzate and / or a salt thereof;
As a component (c), a dispersant for cement comprising a copolymer of a polyalkylene glycol mono (meth) allyl ether compound and a maleic acid ester of a polyalkylene glycol compound and / or a salt thereof, Patent Publication No. 250
No. 8113, copolymer of polyalkylene glycol ester of (meth) acrylic acid and (meth) acrylic acid (salt) as component A, specific polyethylene glycol polypropylene glycol compound as component B, specific interface as component C Concrete admixture consisting of activator,
JP-A-62-216950, polyethylene (propylene) glycol ester of (meth) acrylic acid or polyethylene (propylene) glycol mono (meth) allyl ether, (meth) allylsulfonic acid (salt), (meth) acrylic acid (salt) ), A copolymer comprising:
Copolymer of polyethylene (propylene) glycol ester of (meth) acrylic acid, (meth) allyl sulfonic acid (salt), (meth) acrylic acid (salt) as in 26757, and (meth) as in JP-B 5-36377 Polyethylene (propylene) glycol ester of acrylic acid,
Copolymers of (meth) allylsulfonic acid (salt) or p- (meth) allyloxybenzenesulfonic acid (salt) and (meth) acrylic acid (salt), JP-A-4-14956
Copolymers of polyethylene glycol mono (meth) allyl ether and maleic acid (salt) as described in JP-A-5-17
Polyethylene glycol ester of (meth) acrylic acid such as 0501, (meth) allylsulfonic acid (salt),
(Meth) acrylic acid (salt), alkanediol mono (meth) acrylate, polyalkylene glycol mono (meth) acrylate, α, β- having an amide group in the molecule
Copolymers comprising unsaturated monomers, JP-A-6-19191
8, polyethylene glycol mono (meth) allyl ether, polyethylene glycol mono (meth) acrylate, alkyl (meth) acrylate, (meth)
Copolymers of acrylic acid (salt), (meth) allylsulfonic acid (salt) or p- (meth) allyloxybenzenesulfonic acid (salt), and alkoxypolyalkylene glycol monoallyl ether as disclosed in JP-A-5-43288. A copolymer with maleic anhydride, or a hydrolyzate or a salt thereof, such as polyethylene glycol monoallyl ether, maleic acid as described in JP-B-58-38380, and a monomer copolymerizable with these monomers Copolymers or salts or esters thereof, JP-B-59-1
Polyalkylene glycol mono (meth) such as 8338
Acrylic ester monomers, (meth) acrylic ester monomers, and copolymers composed of monomers copolymerizable with these monomers, sulfonic acid groups as disclosed in JP-A-62-119147. (Meth) acrylic acid ester having, and, if necessary, a copolymer comprising a monomer copolymerizable therewith, or a salt thereof, as disclosed in JP-A-6-271347, in which an alkoxypolyalkylene glycol monoallyl ether is mixed with maleic anhydride. Esterification reaction product of a copolymer and a polyoxyalkylene derivative having an alkenyl group at a terminal, a copolymer of an alkoxypolyalkylene glycol monoallyl ether and maleic anhydride and a hydroxyl group at a terminal as disclosed in JP-A-6-298555 Polycarboxylic acids (salts) such as an esterification reaction product with a polyoxyalkylene derivative; and the like. It can be a plurality of combinations of these known cement dispersing agent it is also possible.

When these known cement dispersants are used in combination, they cannot be unambiguously determined due to differences in the type, composition and test conditions of the cement dispersants to be used. Is 5 to 95:95 to 5, preferably 10 to 90: 9.
It is in the range of 0-10.

Further, the cement additive of the present invention can be used in combination with other known cement additives (materials) as exemplified below.

(1) Water-soluble polymer: unsaturated carboxylic acid polymerization such as polyacrylic acid (sodium), polymethacrylic acid (sodium), polymaleic acid (sodium), and sodium salt of acrylic acid / maleic acid copolymer object;
Polyoxyethylene or polyoxypropylene polymers such as polyethylene glycol and polypropylene glycol or copolymers thereof; methylcellulose,
Nonionic cellulose ethers such as ethylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, carboxymethylcellulose, carboxyethylcellulose and hydroxypropylcellulose; yeast glucan, xanthan gum, β-1.3 glucan (linear, branched chain) Polysaccharides produced by microbial fermentation such as curdlan, baramiron, bakiman, scleroglucan, laminaran, etc.); polyacrylamide; polyvinyl alcohol; starch; starch phosphate; alginic acid Sodium; gelatin; copolymers of acrylic acid having an amino group in the molecule and quaternary compounds thereof.

(2) Polymer emulsions: copolymers of various vinyl monomers such as alkyl (meth) acrylate and the like.

(3) Delaying agents: gluconic acid, glucoheptonic acid, arabonic acid, malic acid or citric acid, and inorganic or organic salts thereof such as sodium, potassium, calcium, magnesium, ammonium, triethanolamine, etc. Oxycarboxylic acid; monosaccharides such as glucose, fructose, galactose, saccharose, xylose, abitose, repose, and isomerized sugar; oligosaccharides such as disaccharide, trisaccharide; and oligosaccharides such as dextrin;
Or polysaccharides such as dextran; saccharides such as molasses containing them; sugar alcohols such as sorbitol; magnesium silicofluoride; phosphoric acid and salts or borates thereof; aminocarboxylic acids and salts thereof; Humic acid; tannic acid; phenol; polyhydric alcohols such as glycerin; aminotri (methylenephosphonic acid), 1-hydroxyethylidene-1,1-diphosphonic acid, ethylenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta (methylenephosphonic acid) and Phosphonic acids such as alkali metal salts and alkaline earth metal salts thereof and derivatives thereof;

(4) Early strength agent / promoter: calcium chloride,
Calcium nitrite, calcium nitrate, calcium bromide,
Soluble calcium salts such as 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 agents: kerosene, liquid paraffin and the like.

(6) Oil-based antifoaming agents: animal and vegetable oils, sesame oil,
Castor oil, their alkylene oxide adducts and the like.

(7) Fatty acid antifoaming agents: oleic acid, stearic acid, alkylene oxide adducts thereof and the like.

(8) Fatty acid ester antifoaming agents: glycerin monoricinoleate, alkenyl succinic acid derivatives, sorbitol monolaurate, sorbitol trioleate, natural wax and the like.

(9) Oxyalkylene-based antifoaming agents: polyoxyalkylenes such as (poly) oxyethylene (poly) oxypropylene adduct; diethylene glycol heptyl ether, polyoxyethylene oleyl ether;
(Poly) oxyalkyl ethers such as polyoxypropylene butyl ether, polyoxyethylene polyoxypropylene 2-ethylhexyl ether, and oxyethylene oxypropylene adducts to higher alcohols having 12 to 14 carbon atoms; polyoxypropylene phenyl ether, polyoxy (Poly) oxyalkylene (alkyl) aryl ethers such as ethylene nonylphenyl ether; 2,4,7,9-tetramethyl-5-decyne-
4,7-diol, 2,5-dimethyl-3-hexyne-
Acetylene ethers obtained by addition-polymerizing an alkylene oxide to acetylene alcohol such as 2,5-diol, 3-methyl-1-butyn-3-ol; diethylene glycol oleate, diethylene glycol laurate, ethylene glycol distearate, etc. (Poly) oxyalkylene fatty acid esters;
(Poly) oxyalkylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monolaurate and polyoxyethylene sorbitan trioleate; (poly) oxy such as sodium polyoxypropylene methyl ether sulfate and sodium polyoxyethylene dodecyl phenol ether sulfate Alkylene alkyl (aryl) ether sulfates; (poly)
(Poly) such as oxyethylene stearyl phosphate
Oxyalkylenealkyl phosphates; (poly) oxyalkylenealkylamines such as polyoxyethylene laurylamine; polyoxyalkyleneamides;

(10) Alcohol-based antifoaming agents: octyl alcohol, hexadecyl alcohol, acetylene alcohol, glycols and the like.

(11) Amide-based antifoaming agent: acrylate polyamine and the like.

(12) Phosphate ester antifoaming agents: tributyl phosphate, sodium octyl phosphate and the like.

(13) Metallic soap-based antifoaming agents: aluminum stearate, calcium oleate and the like.

(14) Silicone antifoaming agents: 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, a protein material, alkenyl sulfosuccinic acid, α-
Olefin sulfonates and the like.

(16) Other surfactants: 6 to 3 per molecule such as octadecyl alcohol and stearyl alcohol.
Aliphatic monohydric alcohol having 0 carbon atoms, alicyclic monohydric alcohol having 6 to 30 carbon atoms in a molecule such as abiethyl alcohol, 6 to 30 carbon atoms in a molecule such as dodecyl mercaptan, etc. Monovalent mercaptans having atoms, nonylphenols and the like, alkylphenols having 6 to 30 carbon atoms in the molecule, dodecylamines and the like having 6 to 30 carbon atoms in the molecule, molecules such as lauric acid and stearic acid Polyalkylene oxide derivatives in which an alkylene oxide such as ethylene oxide or propylene oxide is added in an amount of 10 mol or more to a carboxylic acid having 6 to 30 carbon atoms therein; and may have an alkyl group or an alkoxy group as a substituent. Alkyl diphenyl ether in which two phenyl groups having a sulfone group are ether-bonded Sulfonates; various anionic surfactants; various cationic surfactants such as alkylamine acetate and alkyltrimethylammonium chloride; various nonionic surfactants; various amphoteric surfactants.

(17) Waterproofing agent: fatty acid (salt), fatty acid ester, oil and fat, silicon, paraffin, asphalt,
Wax and the like.

(18) Rust inhibitor: nitrite, phosphate, zinc oxide, etc.

(19) Crack reducing agent: polyoxyalkyl ethers; alkanediols such as 2-methyl-2,4-pentanediol and the like.

(20) Expansive materials: ettringite, coal, etc.

Other known cement additives (materials) include cement wetting agents, thickening agents, separation reducing agents, flocculants,
Drying shrinkage reducing agent, strength enhancer, self-leveling agent, rust inhibitor, coloring agent, fungicide, blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica fume, silica powder, gypsum, etc. It is also possible to use a plurality of these known cement additives (materials) in combination.

Particularly preferred embodiments include the following 1) to
3).

1) Combination of two essential components of the cement additive of the present invention and lignin sulfonate. still,
The compounding weight ratio of the cement additive of the present invention to the lignin sulfonate is preferably in the range of 5 to 95:95 to 5, more preferably 10 to 90:90 to 10.

2) Combination essentially comprising two components of the cement additive of the present invention and an oxyalkylene-based antifoaming agent.
Incidentally, the compounding weight ratio of the oxyalkylene-based antifoaming agent is 0.01 to 1 with respect to the cement additive of the present invention.
A range of 0% by weight is preferred.

3) The cement additive of the present invention, a polyalkylene glycol mono (meth) acrylate monomer, a (meth) acrylate monomer as described in JP-B-59-18338, and a monomer thereof. A combination comprising three components of a copolymer comprising a monomer copolymerizable with the polymer and an oxyalkylene-based antifoaming agent. Incidentally, the compounding weight ratio of the oxyalkylene-based defoaming agent is 0.1% with respect to the total amount of the copolymer with the cement additive of the present invention.
The range of 01 to 10% by weight is preferred.

The cement additive of the present invention comprises 0.01 to 1.0%, preferably 0.02 to 0.5% of the weight of cement.
What is necessary is just to add the amount of the ratio which becomes By this addition, various preferable effects such as reduction of the unit water amount, increase of the strength, improvement of the durability, and the like are brought. If the used amount is less than 0.01%, the performance is insufficient. Conversely, if the used amount exceeds 1.0%, the effect is substantially flattened and disadvantageous in terms of economy.

[0055]

The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to these examples. In the examples,% is% by weight unless otherwise specified.
And parts represent parts by weight.

[Molecular Weight Distribution Measurement Conditions] Model Waters LCM1 Detector Waters 410 Eluent Type Acetonitrile / water = 40/60 Vol% PH6.0 Flow Rate 0.6 (ml / min) Column Type TSK-GEL manufactured by Tosoh Corporation G4000 SWXL + G4000SWXL + G4000SWXL + GUARD COL UMN Each 7.8 × 300 mm, 6.0 × 40 mm Calibration curve Polyethylene glycol standard [Method for measuring carboxylic acid value] Carboxylic acid value: 1 g of copolymer (A) Calculated) means the number of mg of potassium hydroxide equivalent to the carboxylic acid group contained in the carboxylic acid group.

About 1 g of the copolymer (A) was weighed, and 0.1N
HCl to pH 2.0 or less. Next, potentiometric titration was performed with an aqueous potassium hydroxide solution, and the carboxylic acid value was determined from the obtained titration value.

[Hydroxyl value] Hydroxyl value: means the number of mg of potassium hydroxide equivalent to the hydroxyl group contained in 1 g of copolymer (A) (carboxylic acid is converted to sodium carboxylate).

About 5 g of the copolymer (A) is weighed, 5 ml of an acetylating reagent (acetic anhydride / pyridine = 2/7) is added, and the mixture is stirred at 100 ° C. for 30 minutes. 50m distilled water after cooling
1 was added, and the hydroxyl value was determined by performing a back titration by potentiometric titration using a 0.5 N aqueous solution of potassium hydroxide.

Example 1 A glass reactor equipped with a thermometer, stirrer, dropping funnel, nitrogen inlet tube and flow cooler was charged with 37.8 g of ion-exchanged water and polyethylene glycol 3
-Methyl-3-butenyl ether (number average molecular weight 229
1, average number of moles of ethylene oxide added 50) 80 g
Then, 8.3 g of maleic acid was charged and the temperature was raised to 60 ° C., and an aqueous solution in which 1.06 g of sodium persulfate was dissolved in 21.0 g of ion-exchanged water was added dropwise thereto over 180 minutes. Thereafter, the temperature was maintained at 60 ° C. for 120 minutes to complete the polymerization reaction, thereby obtaining the cement additive (1) of the present invention. Weight average molecular weight 29,000, carboxylic acid value 8
7.0 mgKOH / g, hydroxyl value 21.4 mgKOH / g
g.

Comparative Example 1 A glass reactor equipped with a thermometer, stirrer, dropping funnel, nitrogen inlet tube and flow cooler was charged with 37.8 g of ion-exchanged water and polyethylene glycol 3
-Methyl-3-butenyl ether (number average molecular weight 162
5. Average number of moles of ethylene oxide added 35) 80 g
Then, 8.3 g of maleic acid was charged and the temperature was raised to 60 ° C., and an aqueous solution in which 1.06 g of sodium persulfate was dissolved in 21.0 g of ion-exchanged water was added dropwise thereto over 180 minutes. Thereafter, the temperature was maintained at 60 ° C. for 120 minutes to complete the polymerization reaction, and Comparative Cement Additive (1) was obtained. Weight average molecular weight 30,000, carboxylic acid value 8
7.4 mg KOH / g, hydroxyl value 30.3 mg KOH / g
g.

<Comparative Example 2> 37.8 g of ion-exchanged water and polyethylene glycol 3 were placed in a glass reactor equipped with a thermometer, a stirrer, a dropping funnel, a nitrogen inlet tube and a flow cooler.
-Methyl-3-butenyl ether (number average molecular weight 404
6. Average number of moles of ethylene oxide added 90) 80 g
Then, 8.3 g of maleic acid was charged and the temperature was raised to 60 ° C., and an aqueous solution in which 1.06 g of sodium persulfate was dissolved in 21.0 g of ion-exchanged water was added dropwise thereto over 180 minutes. Thereafter, the temperature was maintained at 60 ° C. for 120 minutes to complete the polymerization reaction, thereby obtaining Comparative Cement Additive (2). Weight average molecular weight 33,000, carboxylic acid value 8
7.3 mg KOH / g, hydroxyl value 12.1 mg KOH / g
g.

<Example 2, Comparative Examples 3 and 4> Using a polymer aqueous solution of the cement additive (1) of the present invention and a polymer aqueous solution of the comparative cement additives (1) and (2), a mortar was used. The flow values were compared.

[Concrete test] As a cement, ordinary Portland cement (3 brands equivalent mixture: specific gravity 3.1)
6), mixed sand of land sand from Oigawa water system and mountain sand from Kisarazu (specific gravity 2.62, FM 2.71) as fine aggregate, and hard sandstone crushed stone from Ome (specific gravity 2.64, MS 20 mm) as coarse aggregate
Was used.

The mixing condition of the plain concrete containing no cement additive is that the unit cement amount is 320 kg / m.
3. Unit water volume 203kg / m3 (water / cement ratio 63.4)
%) And the fine aggregate ratio is 49%, and the compounding conditions of the concrete containing the cement additive are as follows.
kg / m 3, unit water amount 166 kg / m 3 (water / cement ratio 51.9%) and fine aggregate ratio 47%.

Under the above conditions, concrete was manufactured with a kneading amount of 30 L, and the slump value and the air amount were measured. In addition,
For the concrete kneading, a forced kneading mixer was used, and the method of measuring the slump and air volume was determined according to Japanese Industrial Standards (JIS A).
1101, 1128). Table 1 shows the results
Shown in

[0067]

[Table 1]

From Table 1, it is found that the required additive amount for obtaining a slump value of 18.0 cm and a flow value of 300 mm is 0.125 wt% for the cement additive (1) of the present invention, and the comparative cement additives (2) and (3). Is 0.150 wt%. Accordingly, it can be seen that the cement additive (1) of the present invention has about 20% improvement in water-reduction in comparison with the comparative cement additives (2) and (3).

[0069]

By using a monomer having a specific number average molecular weight and using a cement additive containing a specific copolymer (A) having a limited composition ratio, carboxylic acid value and hydroxyl value,
A high water reduction rate of a cement composition such as concrete and mortar can be achieved.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Shogo Iwai 14-1 Chidoricho, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Nippon Shokubai Co., Ltd.

Claims (1)

[Claims] 1. Polyalkylene glycol 3-methyl-3
-Butenyl ether having a number average molecular weight of 1800 or more and 28
The hydroxyl value obtained by polymerizing a monomer component containing the monomer (I) and the maleic acid-based monomer (II) in a range of less than 00 is 18 to 26 mgKOH / g, and the carboxylic acid value is Copolymer (A) having a range of 65 to 95 mgKOH / g
A cement additive comprising: