JP2015187054A - Cement dispersing agent composition and cement composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a cement dispersing agent composition which can increase an effect of inhibiting decrease in flowability over time under a high temperature environment above about 30°C and can increase curability under a temperature environment at about 20°C; and a cement composition containing such a cement dispersing agent composition.SOLUTION: A cement dispersing agent composition comprises: a boric acid compound; and a polycarboxylic acid-based copolymer including a structural unit (I) derived from an unsaturated polyalkylene glycol-based monomer (a) represented by a specific general formula, and a structural unit (II) derived from an unsaturated carboxylic acid-based monomer (b) represented by a specific general formula.

Description

  The present invention relates to a cement dispersant composition and a cement composition.

  Cement mortar, concrete, and the like are required to have improved fluidity in order to improve the handleability during construction. It is known to add a cement dispersant as a means for improving the fluidity of cement mortar, concrete and the like. By adding such a cement dispersant, the fluidity immediately after the addition, that is, immediately after kneading for preparing cement mortar, concrete, or the like is improved. However, in the addition of such a cement dispersant, there is a problem that the fluidity is lowered as time elapses from the start of kneading, that is, the fluidity is deteriorated with time.

  It has been reported that a boric acid compound is added as a means for suppressing deterioration of fluidity with time in cement mortar, concrete, or the like (for example, Patent Documents 1 and 2).

  Here, cement mortar, concrete, and the like are required to have excellent curability after their construction. However, the improvement in fluidity and the improvement in curability are mutually contradictory properties, and generally there is a problem that the higher the fluidity, the lower the curability.

  Even in the addition of a retarder such as a boric acid compound, the same problem as described above is seen, and although the deterioration of fluidity with time is suppressed by the addition of the retarder, on the other hand, the curability is lowered, and after the construction There is a problem that sufficient curability cannot be exhibited.

  According to a conventionally reported technique for adding a boric acid compound (for example, Patent Document 2), in a high temperature environment of about 30 ° C., it is possible to achieve both the effect of suppressing deterioration of fluidity over time and high curability. Has been. However, according to the boric acid compound addition technique that has been reported in the past, the effect of suppressing deterioration in fluidity over time is further improved in a temperature environment of about 20 ° C. compared to a temperature environment of about 30 ° C. On the other hand, the phenomenon that curability becomes low occurs. Such a phenomenon is caused when the cement hydration reaction is larger in a high temperature environment of about 30 ° C. than in a temperature environment of about 20 ° C., and the hardening delay due to the boric acid compound in the temperature environment of about 20 ° C. It is thought that this is because the effect is greatly expressed.

  Such a boric acid compound addition technique that has been reported so far that the effect of suppressing the temporal deterioration of fluidity in a high temperature environment of about 30 ° C. and high curability in a temperature environment of about 20 ° C. cannot be achieved at the same time. However, there is a big problem when it is adopted for construction of cement mortar, concrete, etc. in an area where a certain temperature change is seen. Such problems are particularly high in areas where the daytime temperature is generally high, when cement mortar, concrete, etc. are constructed, and at night, where temperature is generally low when cement mortar, concrete, etc., is constructed. Is remarkable. In such a region, when adopting the boric acid compound addition technology that has been reported in the past, trying to secure the fluidity during construction during the daytime when the temperature is high, the curability at night when the temperature is low is insufficient. On the other hand, when trying to secure curability at night when the temperature is low, it is necessary to reduce the amount of boric acid compound added, and then the fluidity during construction during daytime when the temperature is high will be low Occurs.

  Accordingly, there is a need for a cement dispersant composition that can increase the effect of suppressing deterioration of fluidity with time in a high temperature environment of about 30 ° C. or higher and can increase curability in a temperature environment of about 20 ° C.

Japanese Patent Laid-Open No. 55-136158 JP-A-6-144905

  An object of the present invention is to provide a cement dispersant composition that can enhance the effect of suppressing deterioration of fluidity over time in a high temperature environment of about 30 ° C. or higher and can increase curability in a temperature environment of about 20 ° C. It is to provide. Moreover, it is providing the cement composition containing such a cement dispersant composition.

（一般式（１）中、Ｒ^１およびＲ^２は、同一または異なって、水素原子またはメチル基を表し、Ｒ^３は、水素原子または炭素原子数１〜３０の炭化水素基を表し、ＡＯは、炭素原子数２〜１８のオキシアルキレン基を表し、ｎは、ＡＯで表されるオキシアルキレン基の平均付加モル数を表し、ｎは１〜５００の整数であり、ｘは０〜２の整数であり、ｙは０または１である。）

（一般式（２）中、Ｒ^４〜Ｒ^６は、同一または異なって、水素原子、メチル基、または−（ＣＨ_２）_ｚＣＯＯＭ基を表し、−（ＣＨ_２）_ｚＣＯＯＭ基は−ＣＯＯＸ基または他の−（ＣＨ_２）_ｚＣＯＯＭ基と無水物を形成していても良く、ｚは０〜２の整数であり、Ｍは、水素原子、アルカリ金属、アルカリ土類金属、アンモニウム基、有機アンモニウム基、または有機アミン基を表し、Ｘは、水素原子、メチル基、エチル基、アルカリ金属、アルカリ土類金属、アンモニウム基、有機アンモニウム基、または有機アミン基を表す。） The cement dispersant composition of the present invention is
Derived from the structural unit (I) derived from the unsaturated polyalkylene glycol monomer (a) represented by the general formula (1) and the unsaturated carboxylic acid monomer (b) represented by the general formula (2) A polycarboxylic acid copolymer containing the structural unit (II) and a boric acid compound.

(In General Formula (1), R ¹ and R ² are the same or different and each represents a hydrogen atom or a methyl group; R ³ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms; Represents an oxyalkylene group having 2 to 18 carbon atoms, n represents the average number of moles added of the oxyalkylene group represented by AO, n is an integer of 1 to 500, and x is an integer of 0 to 2 And y is 0 or 1.)

(In general formula (2), R ^{4 to} R ⁶ are the same or different and each represents a hydrogen atom, a methyl group, or — (CH ₂ ) _z COOM group, and — (CH ₂ ) _z COOM group represents a —COOX group. Or other — (CH ₂ ) _z COOM group may form an anhydride, z is an integer of 0 to 2, M is a hydrogen atom, alkali metal, alkaline earth metal, ammonium group, organic An ammonium group or an organic amine group is represented, and X represents a hydrogen atom, a methyl group, an ethyl group, an alkali metal, an alkaline earth metal, an ammonium group, an organic ammonium group, or an organic amine group.)

  In a preferred embodiment, the mass ratio of the polycarboxylic acid copolymer to the boric acid compound (polycarboxylic acid copolymer: boric acid compound) is 100: 1 to 100: 100.

  The cement composition of the present invention includes the cement dispersant composition of the present invention.

  According to the present invention, by combining a specific polycarboxylic acid copolymer and a boric acid compound, it is possible to increase the effect of suppressing the deterioration of fluidity over time in a high temperature environment of about 30 ° C. or more, and about 20 ° C. It is possible to provide a cement dispersant composition capable of increasing curability in the temperature environment of Also, a cement composition containing such a cement dispersant composition can be provided.

  In the present specification, the expression “(meth) acryl” means “acryl and / or methacryl”, and the expression “(meth) acrylate” means “acrylate and / or methacrylate”. Means “allyl and / or methallyl”, and “(meth) acrolein” means “acrolein and / or methacrole”. It means "rain". Further, in the present specification, the expression “acid (salt)” means “acid and / or salt thereof”.

≪Cement dispersant composition≫
The cement dispersant composition of the present invention contains a specific polycarboxylic acid copolymer and a boric acid compound. The cement dispersant composition of the present invention includes a boric acid compound and a specific polycarboxylic acid-based copolymer, thereby suppressing the fluidity deterioration with time in a high temperature environment of about 30 ° C. or higher. It is possible to achieve an unexpectedly remarkable effect that it can be increased and the curability in a temperature environment of about 20 ° C. can be increased.

  In the cement dispersant composition of the present invention, the mass ratio of the polycarboxylic acid copolymer to the boric acid compound (polycarboxylic acid copolymer: boric acid compound) is preferably 100: 1 to 100: 100. More preferably 100: 3 to 100: 70, still more preferably 100: 5 to 100: 60, and particularly preferably 100: 5 to 100: 50. When the mass ratio of the polycarboxylic acid copolymer and the boric acid compound in the cement dispersant composition of the present invention falls within the above range, the cement dispersant composition of the present invention contains a boric acid compound. In addition, by including a specific polycarboxylic acid-based copolymer, it is possible to increase the effect of suppressing deterioration of fluidity over time in a high temperature environment of about 30 ° C. or more, and curability in a temperature environment of about 20 ° C. An unexpectedly remarkable effect that can be increased can be further exhibited.

<Polycarboxylic acid copolymer>
The polycarboxylic acid-based copolymer contained in the cement dispersant composition of the present invention includes the structural unit (I) derived from the unsaturated polyalkylene glycol monomer (a) represented by the general formula (1) and the general And a structural unit (II) derived from the unsaturated carboxylic acid monomer (b) represented by the formula (2).

The structural unit (I) derived from the unsaturated polyalkylene glycol monomer (a) represented by the general formula (1) is specifically represented by the following formula.

The structural unit (II) derived from the unsaturated carboxylic acid monomer (b) represented by the general formula (2) is specifically represented by the following formula.

In general formula (1) and general formula (I), R ¹ and R ² are the same or different and each represents a hydrogen atom or a methyl group.

In General Formula (1) and General Formula (I), R ³ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms. Examples of the hydrocarbon group having 1 to 30 carbon atoms include an alkyl group having 1 to 30 carbon atoms (an aliphatic alkyl group and an alicyclic alkyl group), an alkenyl group having 1 to 30 carbon atoms, and the number of carbon atoms. Examples thereof include an alkynyl group having 1 to 30 carbon atoms and an aromatic group having 6 to 30 carbon atoms. R ³ is preferably a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and more preferably a hydrogen atom or a carbon atom having 1 to 12 carbon atoms in that the effects of the present invention can be further exhibited. It is a hydrogen group, more preferably a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and particularly preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

  In general formula (1) and general formula (I), AO is an oxyalkylene group having 2 to 18 carbon atoms, preferably an oxyalkylene group having 2 to 8 carbon atoms, more preferably the number of carbon atoms. 2 to 4 oxyalkylene groups. When AO is any two or more selected from oxyethylene group, oxypropylene group, oxybutylene group, oxystyrene group, etc., the addition form of AO is random addition, block addition, alternating addition, etc. Either form may be sufficient. In order to secure a balance between hydrophilicity and hydrophobicity, it is preferable that the oxyalkylene group contains an oxyethylene group as an essential component, and more than 50 mol% of the entire oxyalkylene group is an oxyethylene group. Preferably, 90 mol% or more of the entire oxyalkylene group is an oxyethylene group.

  In general formula (1) and general formula (I), n represents the average addition mole number of the oxyalkylene group represented by AO, and is 1-500, Preferably it is 2-500, More preferably, 5 It is -500, More preferably, it is 10-500, Most preferably, it is 15-500, Most preferably, it is 20-300.

  In general formula (1) and general formula (I), x is an integer of 0-2.

  In general formula (1) and general formula (I), y is 0 or 1.

  As the unsaturated polyalkylene glycol monomer (a) represented by the general formula (1), for example, an alkylene oxide having 2 to 8 carbon atoms is added to a saturated aliphatic alcohol having 1 to 20 carbon atoms. Obtained by polymerizing an alkylene oxide having 2 to 18 carbon atoms with an ester of an alkoxypolyalkylene glycol obtained by this method and (meth) acrylic acid or crotonic acid; a saturated aliphatic alcohol having 1 to 20 carbon atoms Esterified products of polyalkylene glycols and (meth) acrylic acid or crotonic acid; C 3-20 unsaturated aliphatic alcohols such as (meth) allyl alcohol, crotyl alcohol, oleyl alcohol, etc. Alkoxypolyalkylene glycols obtained by adding 2 to 8 alkylene oxides And esterified product of (meth) acrylic acid or crotonic acid; unsaturated alkylene alcohols having 3 to 20 carbon atoms such as (meth) allyl alcohol, crotyl alcohol, oleyl alcohol, etc., and alkylene having 2 to 18 carbon atoms Esterified product of polyalkylene glycol obtained by polymerizing oxide and (meth) acrylic acid or crotonic acid; C3-C20 alicyclic alcohol such as cyclohexanol, C2-C8 alkylene An esterified product of an alkoxypolyalkylene glycol obtained by adding an oxide and (meth) acrylic acid or crotonic acid; an alicyclic alcohol having 3 to 20 carbon atoms such as cyclohexanol; Polyalkylene glycols obtained by polymerizing an alkylene oxide of An esterified product of (meth) acrylic acid or crotonic acid; an alkoxypolyalkylene glycol obtained by adding an alkylene oxide having 2 to 8 carbon atoms to an aromatic alcohol having 6 to 20 carbon atoms, and (meth) acrylic An esterified product with an acid or crotonic acid; a polyalkylene glycol obtained by polymerizing an alkylene oxide having 2 to 18 carbon atoms to an aromatic alcohol having 6 to 20 carbon atoms; and (meth) acrylic acid or crotonic acid; And the like.

  The unsaturated polyalkylene glycol monomer (a) represented by the general formula (1) is preferably an alkoxy polyalkylene glycol of (meth) acrylic acid in that the effects of the present invention can be further exhibited. Esters of vinyl alcohol, (meth) allyl alcohol, 3-methyl-3-buten-1-ol, 3-methyl-2-buten-1-ol, 2-methyl-3-buten-2-ol, 2- A compound obtained by adding 1 to 500 mol of alkylene oxide to any of methyl-2-buten-1-ol and 2-methyl-3-buten-1-ol; more preferably 3-methyl-3-butene It is a compound obtained by adding 1 to 500 moles of alkylene oxide to -1-ol.

  The unsaturated polyalkylene glycol monomer (a) represented by the general formula (1) may be only one type or two or more types.

In General Formula (2) and General Formula (II), R ^{4 to} R ⁶ are the same or different and each represents a hydrogen atom, a methyl group, or a — (CH ₂ ) _z COOM group. The — (CH ₂ ) _z COOM group may form an anhydride with the —COOX group or other — (CH ₂ ) _z COOM groups. z is an integer of 0-2.

  M represents a hydrogen atom, a monovalent metal atom, a divalent metal atom, an ammonium group, or an organic ammonium group.

  X represents a hydrogen atom, a methyl group, an ethyl group, a monovalent metal atom, a divalent metal atom, an ammonium group, or an organic ammonium group.

  Examples of the unsaturated carboxylic acid monomer (b) represented by the general formula (2) include monocarboxylic acid monomers such as (meth) acrylic acid and crotonic acid or salts thereof; maleic acid, And dicarboxylic acid monomers such as itaconic acid and fumaric acid or salts thereof; anhydrides of dicarboxylic acid monomers such as maleic acid, itaconic acid and fumaric acid or salts thereof; and the like. Examples of the salt herein include alkali metal salts, alkaline earth metal salts, ammonium salts, organic ammonium salts, and organic amine salts. Examples of the alkali metal salt include lithium salt, sodium salt, potassium salt and the like. Examples of alkaline earth metal salts include calcium salts and magnesium salts. Examples of the organic ammonium salt include methyl ammonium salt, ethyl ammonium salt, dimethyl ammonium salt, diethyl ammonium salt, trimethyl ammonium salt, and triethyl ammonium salt. Examples of organic amine salts include alkanolamine salts such as ethanolamine salts, diethanolamine salts, and triethanolamine salts.

  The unsaturated carboxylic acid monomer (b) represented by the general formula (2) is preferably (meth) acrylic acid, maleic acid, maleic anhydride in that the effects of the present invention can be further exhibited. More preferred are acrylic acid and methacrylic acid.

  The unsaturated carboxylic acid monomer (b) represented by the general formula (2) may be only one kind or two or more kinds.

  The total content of the structural unit (I) and the structural unit (II) in the polycarboxylic acid copolymer contained in the cement dispersant composition of the present invention is preferably 50% by mass to 100% by mass. More preferably 70% by mass to 100% by mass, still more preferably 80% by mass to 100% by mass, particularly preferably 90% by mass to 100% by mass, and most preferably 95% by mass to 100% by mass. %. If the total content of the structural unit (I) and the structural unit (II) in the polycarboxylic acid-based copolymer contained in the cement dispersant composition of the present invention is within the above range, the cement dispersion of the present invention will be described. The agent composition has a remarkable and unexpectedly excellent effect that the effect of suppressing the deterioration of fluidity over time in a high temperature environment of about 30 ° C. or higher can be obtained, and the curability in a temperature environment of about 20 ° C. can be increased. The effect can be further manifested.

  The total content ratio of the structural unit (I) and the structural unit (II) in the polycarboxylic acid copolymer contained in the cement dispersant composition of the present invention is, for example, the polycarboxylic acid copolymer. These can be known by various structural analyzes (for example, NMR). Moreover, it is calculated based on the usage amount of various monomers used when producing the polycarboxylic acid-based copolymer contained in the cement dispersant composition of the present invention without performing various structural analyzes as described above. In the polycarboxylic acid copolymer contained in the cement dispersant composition of the present invention, the structural unit (I) and the structural unit (II) of the structural unit derived from the various monomers It is good also as a total content rate. That is, the unsaturated polyalkylene glycol monomer (a) and the unsaturated carboxylic acid in all the monomer components used in producing the polycarboxylic acid copolymer contained in the cement dispersant composition of the present invention. The content ratio of the total mass with the acid monomer (b) is the structural unit (I) and the structural unit (II) in the polycarboxylic acid copolymer contained in the cement dispersant composition of the present invention. May be treated as the total content ratio.

  In the polycarboxylic acid copolymer contained in the cement dispersant composition of the present invention, in addition to the structural unit (I) and the structural unit (II), the structural unit derived from another monomer (c) (III ) May be included.

  The monomer (c) is a monomer copolymerizable with the monomer (a) and the monomer (b). Only one type of monomer (c) may be used, or two or more types may be used.

  As the monomer (c), for example, hydroxyalkyl (meth) acrylates such as hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate; unsaturated monomethyl such as methyl (meth) acrylate and glycidyl (meth) acrylate Esters of carboxylic acids and alcohols having 1 to 30 carbon atoms; various (alkoxy) (poly) alkylene glycol mono (meth) such as polyethylene glycol mono (meth) acrylate and methoxy (poly) ethylene glycol mono (meth) acrylate Acrylates; (anhydrous) half esters of unsaturated dicarboxylic acids such as maleic acid, fumaric acid and itaconic acid and alcohols having 1 to 30 carbon atoms; (anhydrous) unsaturated such as maleic acid, fumaric acid and itaconic acid Dicarboxylic acids and carbon atoms 1 Diesters with 0 alcohol; half amides of the above unsaturated dicarboxylic acids and amines having 1 to 30 carbon atoms; diamides of the above unsaturated dicarboxylic acids and amines having 1 to 30 carbon atoms; Half esters of an alkyl (poly) alkylene glycol obtained by adding 1 to 500 moles of an alkylene oxide having 2 to 18 carbon atoms to an amine and the above unsaturated dicarboxylic acids; alkylene having 2 to 18 carbon atoms to the above alcohol or amine Diesters of alkyl (poly) alkylene glycols to which 1 to 500 moles of oxide have been added and the above unsaturated dicarboxylic acids; the above unsaturated dicarboxylic acids and glycols having 2 to 18 carbon atoms or the number of moles of these glycols added 2 to 2 500 half-esters with 500 polyalkylene glycols; Diesters of unsaturated dicarboxylic acids and glycols having 2 to 18 carbon atoms or addition of these glycols with polyalkylene glycols having 2 to 500 moles; addition of maleamic acid and glycols having 2 to 18 carbon atoms or these glycols Half amides with polyalkylene glycols having 2 to 500 moles; (poly) alkylene glycol di (meth) acrylates such as (poly) ethylene glycol di (meth) acrylate and (poly) propylene glycol di (meth) acrylate; Polyfunctional (meth) acrylates such as hexanediol di (meth) acrylate and trimethylolpropane tri (meth) acrylate; (poly) alkylene glycol dimaleates such as polyethylene glycol dimaleate; vinyl sulfonate, (meth) ali Unsaturated sulfonic acids (salts) such as sulfonic acid, 2-methylpropanesulfonic acid (meth) acrylamide and styrenesulfonic acid; unsaturated monocarboxylic acids such as methyl (meth) acrylamide and amines having 1 to 30 carbon atoms; Amides; vinyl aromatics such as styrene, α-methylstyrene, vinyltoluene; alkanediol mono (meth) acrylates such as 1,4-butanediol mono (meth) acrylate; dienes such as butadiene and isoprene; Unsaturated amides such as (meth) acrylic (alkyl) amide, N-methylol (meth) acrylamide, N, N-dimethyl (meth) acrylamide; Unsaturated cyanates such as (meth) acrylonitrile; Unsaturation such as vinyl acetate Esters: aminoethyl (meth) acrylate, dimethacrylate Unsaturated amines such as tilaminoethyl and vinylpyridine; Divinyl aromatics such as divinylbenzene; Allyls such as (meth) allyl alcohol and glycidyl (meth) allyl ether; Vinyl ethers such as (methoxy) polyethylene glycol monovinyl ether (Meth) allyl ethers such as (methoxy) polyethylene glycol mono (meth) allyl ether;

  The content ratio of the structural unit (III) in the polycarboxylic acid copolymer that can be contained in the cement dispersant composition of the present invention is, for example, various structural analyzes of the polycarboxylic acid copolymer (for example, NMR) ) Moreover, based on the usage amount of various monomers used when producing the polycarboxylic acid-based copolymer that can be included in the cement dispersant composition of the present invention without performing various structural analyzes as described above. The calculated content ratio of the structural units derived from the various monomers may be the content ratio of the structural unit (III) in the polycarboxylic acid copolymer that can be included in the cement dispersant composition of the present invention. That is, the content ratio of the mass of the other monomer (c) in all the monomer components used when producing the polycarboxylic acid-based copolymer that can be included in the cement dispersant composition of the present invention is set as follows. You may handle as a content rate of structural unit (III) in the polycarboxylic acid-type copolymer which can be contained in the cement dispersant composition of invention.

  The content ratio of the structural unit (I), the structural unit (II), and the structural unit (III) in the polycarboxylic acid-based copolymer contained in the cement dispersant composition of the present invention is a mass ratio (mass%). Preferably, (I) / (II) / (III) = 1 to 99/1 to 99/0 to 70, and more preferably (I) / (II) / (III) = 50 to 99 / 1 to 50/0 to 49, more preferably (I) / (II) / (III) = 55 to 98/2 to 45/0 to 40, and particularly preferably (I) / (II ) / (III) = 60 to 97/3 to 40/0 to 30.

  The mass average molecular weight (Mw) of the polycarboxylic acid copolymer contained in the cement dispersant composition of the present invention is preferably as a mass average molecular weight (Mw) in terms of polyethylene glycol by gel permeation chromatography (GPC). It is 1000-500000, More preferably, it is 5000-300000, More preferably, it is 10,000-150,000. Since the weight average molecular weight (Mw) of the polycarboxylic acid copolymer contained in the cement dispersant composition of the present invention falls within the above range, the cement dispersant composition of the present invention has a high temperature of about 30 ° C. or higher. It is possible to further exhibit an unexpectedly remarkable effect that the effect of suppressing the deterioration of fluidity over time in a temperature environment of 2 can be increased and the curability in a temperature environment of about 20 ° C. can be increased.

  The polycarboxylic acid copolymer contained in the cement dispersant composition of the present invention can be produced by any suitable method. The polycarboxylic acid copolymer contained in the cement dispersant composition of the present invention preferably contains an unsaturated polyalkylene glycol monomer (a) and an unsaturated carboxylic acid monomer (b). The monomer component can be produced by polymerization in the presence of a polymerization initiator.

  An unsaturated polyalkylene glycol-based monomer (a), an unsaturated carboxylic acid-based monomer (b) that can be used in the production of the polycarboxylic acid-based copolymer contained in the cement dispersant composition of the present invention, and As needed, the usage-amount of another monomer (c) is derived from each monomer in all the structural units which comprise the polycarboxylic acid-type copolymer contained in the cement dispersant composition of this invention. What is necessary is just to adjust suitably so that the ratio of a structural unit may become what was mentioned above. Preferably, as the polymerization reaction proceeds quantitatively, the structural units derived from the respective monomers in all the structural units constituting the polycarboxylic acid-based copolymer contained in the cement dispersant composition of the present invention described above. Each monomer may be used in the same ratio as the ratio.

  The unsaturated polyalkylene glycol monomer (a) can be synthesized by any appropriate method. For example, it can be synthesized by adding an alkylene oxide to an unsaturated alcohol such as allyl alcohol, methallyl alcohol, 3-methyl-3-buten-1-ol (isoprenol), hydroxyethyl vinyl ether, hydroxybutyl vinyl ether or the like.

  The polymerization of the monomer component can be performed by any appropriate method. Examples thereof include solution polymerization and bulk polymerization. Examples of the solution polymerization method include a batch method and a continuous method. Solvents that can be used for solution polymerization include water; alcohols such as methyl alcohol, ethyl alcohol, and isopropyl alcohol; aromatic or aliphatic hydrocarbons such as benzene, toluene, xylene, cyclohexane, and n-hexane; esters such as ethyl acetate. Compounds; ketone compounds such as acetone and methyl ethyl ketone; cyclic ether compounds such as tetrahydrofuran and dioxane; and the like.

  When the monomer component is polymerized, a water-soluble polymerization initiator, for example, a persulfate such as ammonium persulfate, sodium persulfate, or potassium persulfate; hydrogen peroxide; 2,2′- Azoamidine compounds such as azobis-2-methylpropionamidine hydrochloride, cyclic azoamidine compounds such as 2,2′-azobis-2- (2-imidazolin-2-yl) propane hydrochloride, 2-carbamoylazoisobutyronitrile, etc. Water-soluble azo initiators such as azonitrile compounds of These polymerization initiators include alkali metal sulfites such as sodium hydrogen sulfite, metabisulfites, sodium hypophosphite, Fe (II) salts such as molle salts, sodium hydroxymethanesulfinate dihydrate, hydroxylamine hydrochloride Accelerators such as salt, thiourea, L-ascorbic acid (salt), and erythorbic acid (salt) can also be used in combination. Among these combined forms, a combination of hydrogen peroxide and an accelerator such as L-ascorbic acid (salt) is preferable. These polymerization initiators and accelerators may be used alone or in combination of two or more.

  When performing solution polymerization using a lower alcohol, aromatic hydrocarbon, aliphatic hydrocarbon, ester compound, or ketone compound as a solvent, or when performing bulk polymerization, benzoyl peroxide, lauroyl peroxide may be used as a polymerization initiator. Peroxides such as oxide and sodium peroxide; hydroperoxides such as t-butyl hydroperoxide and cumene hydroperoxide; azo compounds such as azobisisobutyronitrile; When such a polymerization initiator is used, an accelerator such as an amine compound can be used in combination. Furthermore, when a water-lower alcohol mixed solvent is used, it can be appropriately selected from the above-mentioned various polymerization initiators or combinations of polymerization initiators and accelerators.

  The reaction temperature for the polymerization of the monomer component is appropriately determined depending on the polymerization method, solvent, polymerization initiator, and chain transfer agent used. The reaction temperature is preferably 0 ° C. or higher, more preferably 30 ° C. or higher, further preferably 50 ° C. or higher, preferably 150 ° C. or lower, more preferably 120 ° C. or lower. More preferably, it is 100 ° C. or lower.

  Any appropriate method can be adopted as a method of charging the monomer component into the reaction vessel. As such a charging method, for example, a method in which the entire amount is initially charged into the reaction vessel, a method in which the entire amount is divided or continuously charged into the reaction vessel, a part is initially charged in the reaction vessel, and the rest is put in the reaction vessel. The method of dividing | segmenting or carrying out continuously etc. is mentioned. Specifically, a method in which the total amount of monomer (a) and the total amount of monomer (b) are continuously charged into the reaction vessel, a part of monomer (a) is initially charged into the reaction vessel, A method in which the remainder of the monomer (a) and the entire amount of the monomer (b) are continuously charged into the reaction vessel, a part of the monomer (a) and a part of the monomer (b) in the reaction vessel In the initial stage, and the remainder of the monomer (a) and the remainder of the monomer (b) are alternately fed into the reaction vessel in several divided portions. Furthermore, by changing the charging rate of each monomer into the reaction vessel during the reaction continuously or stepwise, the charging mass ratio per unit time of each monomer is changed continuously or stepwise, You may make it synthesize | combine simultaneously the 2 or more types of copolymer from which the ratio of structural unit (I) and structural unit (II) differs. The polymerization initiator may be charged into the reaction vessel from the beginning, may be dropped into the reaction vessel, or these may be combined according to the purpose.

  In the polymerization of the monomer component, a chain transfer agent can be preferably used. When a chain transfer agent is used, the molecular weight of the resulting copolymer can be easily adjusted. Only one type of chain transfer agent may be used, or two or more types may be used.

  Any appropriate chain transfer agent can be adopted as the chain transfer agent. Examples of such chain transfer agents include thiol chain transfer agents such as mercaptoethanol, thioglycerol, thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thiomalic acid, and 2-mercaptoethanesulfonic acid; Secondary alcohols such as isopropanol; phosphorous acid, hypophosphorous acid, and salts thereof (sodium hypophosphite, potassium hypophosphite, etc.), sulfurous acid, hydrogen sulfite, dithionite, metabisulfite, And lower salts of salts thereof (sodium sulfite, potassium sulfite, sodium hydrogen sulfite, potassium hydrogen sulfite, sodium dithionite, potassium dithionite, sodium metabisulfite, potassium metabisulfite, etc.) and salts thereof, etc. Is mentioned.

  The produced polycarboxylic acid copolymer can be used as it is as the polycarboxylic acid copolymer contained in the cement dispersant composition of the present invention. However, from the viewpoint of handleability, the polycarboxylic acid copolymer is used. It is preferable to adjust the pH of the reaction solution after the production of the polymer to 5 or more. However, in order to improve the polymerization rate, it is preferable to perform the polymerization at a pH of less than 5 and adjust the pH to 5 or more after the polymerization. The pH can be adjusted, for example, using an alkaline substance such as an inorganic salt such as monovalent metal or divalent metal hydroxide or carbonate; ammonia; organic amine;

  The produced polycarboxylic acid-based copolymer can be subjected to concentration adjustment, if necessary, with respect to the solution obtained by the production.

  The produced polycarboxylic acid copolymer may be used as it is in the form of a solution, or after neutralization with a divalent metal hydroxide such as calcium or magnesium to obtain a polyvalent metal salt. You may use it by making it dry or carrying | supporting to inorganic powders, such as a silica type fine powder, and making it dry.

<Boric acid compound>
Examples of the boric acid compound contained in the cement dispersant composition of the present invention include boric acid (salt), boric anhydride (salt), perboric acid (salt), metaboric acid (salt), and tetraboric acid (salt). (4 boric acid (salt)), pyroboric acid (salt), borax, and carnit. Examples of the salt include sodium salt, potassium salt, calcium salt, aluminum salt, strontium salt, and ammonium salt.

<Other ingredients>
The cement dispersant composition of the present invention may contain any appropriate other component in addition to the polycarboxylic acid copolymer and boric acid compound as long as the effects of the present invention are not impaired.

  Examples of other components include a cement dispersant. When a cement dispersant is used, the blending ratio of the polycarboxylic acid copolymer and the cement dispersant contained in the cement dispersant composition of the present invention (polycarboxylic acid copolymer / cement dispersant) is used. Any appropriate blending ratio can be set depending on the type of cement dispersant to be used, blending conditions, test conditions, and the like. Such a blending ratio is preferably 50 to 100/50 to 0, more preferably 60 to 100/40 to 0, and still more preferably 70 to 50% as a mass ratio (mass%) in terms of solid content. 100 / 30-0. Only one cement dispersant may be used, or two or more cement dispersants may be used.

  Examples of the cement dispersant include a sulfonic acid-based dispersant having a sulfonic acid group in the molecule, and a polycarboxylic acid-based dispersant other than the polycarboxylic acid-based copolymer contained in the cement dispersant composition of the present invention. Can be mentioned.

  Examples of the sulfonic acid-based dispersant include polyalkylaryl sulfonate-based sulfonic acid-based dispersants such as naphthalene sulfonic acid formaldehyde condensate, methyl naphthalene sulfonic acid formaldehyde condensate and anthracene sulfonic acid formaldehyde condensate; melamine sulfonic acid Melamine formalin sulfonate-based sulfonic acid dispersants such as formaldehyde condensates; Aromatic amino sulfonate-based sulfonic acid dispersants such as aminoaryl sulfonic acid-phenol-formaldehyde condensates; lignin sulfonates, Examples thereof include lignin sulfonate sulfonic acid dispersants such as modified lignin sulfonate; polystyrene sulfonate sulfonic acid dispersants;

  The cement dispersant composition of the present invention can contain any appropriate other cement additive (material) as long as the effects of the present invention are not impaired. Examples of such other cement additives (materials) include other cement additives (materials) exemplified in the following (1) to (12). The blending ratio of the polycarboxylic acid copolymer contained in the cement dispersant composition of the present invention and such other cement additives (materials) depends on the type and purpose of the other cement additives (materials) used. Any suitable blending ratio may be employed accordingly.

(1) Water-soluble polymer substances: nonionic cellulose ethers such as methylcellulose, ethylcellulose, carboxymethylcellulose; polysaccharides produced by microbial fermentation such as yeast glucan, xanthan gum, β-1.3 glucans; polyethylene glycol, etc. Polyoxyalkylene glycols; polyacrylamide and the like.

(2) Polymer emulsion: Copolymers of various vinyl monomers such as alkyl (meth) acrylate.

(3) Curing retarder: oxycarboxylic acid or salt thereof such as gluconic acid, glucoheptonic acid, alabonic acid, malic acid, citric acid; sugar and sugar alcohol; polyhydric alcohol such as glycerin; aminotri (methylenephosphonic acid) Phosphonic acid and its derivatives.

(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) Oxyalkylene-based antifoaming agent: polyoxyalkylenes such as (poly) oxyethylene (poly) oxypropylene adducts; polyoxyalkylene alkyl ethers such as diethylene glycol heptyl ether; polyoxyalkylene acetylene ethers; ) Oxyalkylene fatty acid esters; polyoxyalkylene sorbitan fatty acid esters; polyoxyalkylene alkyl (aryl) ether sulfate salts; polyoxyalkylene alkyl phosphate esters; polyoxypropylene polyoxyethylene laurylamine (propylene oxide 1-20) Mole additions, ethylene oxide 1-20 mol adducts, etc.), fatty acid-derived amines obtained from cured beef tallow added with alkylene oxide (propylene oxide 1-20 mol) Additionally, polyoxyalkylene alkyl amines ethylene oxide 20 mol adduct) or the like; polyoxyalkylene amide.

(6) Antifoaming agents other than oxyalkylene type: Mineral oil type, fat type, fatty acid type, fatty acid ester type, alcohol type, amide type, phosphate ester type, metal soap type, silicone type and the like.

(7) AE agent: resin soap, saturated or unsaturated fatty acid, sodium hydroxystearate, lauryl sulfate, ABS (alkylbenzene sulfonic acid), alkane sulfonate, polyoxyethylene alkyl (phenyl) ether, polyoxyethylene alkyl (phenyl) ether Sulfate ester or a salt thereof, polyoxyethylene alkyl (phenyl) ether phosphate ester or a salt thereof, protein material, alkenyl sulfosuccinic acid, α-olefin sulfonate and the like.

(8) Other surfactants: various anionic surfactants; various cationic surfactants such as alkyltrimethylammonium chloride; various nonionic surfactants; various amphoteric surfactants.

(9) Waterproofing agent: fatty acid (salt), fatty acid ester, fats and oils, silicon, paraffin, asphalt, wax and the like.

(10) Rust inhibitor: nitrite, phosphate, zinc oxide and the like.

(11) Crack reducing agent: polyoxyalkyl ether and the like.

(12) Expansion material: Ettlingite, coal, etc.

  Other known cement additives (materials) include cement wetting agents, thickeners, separation reducing agents, flocculants, drying shrinkage reducing agents, strength enhancers, self-leveling agents, rust preventives, colorants, and antifungal agents. An agent etc. can be mentioned. These known cement additives (materials) may be used alone or in combination of two or more.

≪Cement composition≫
The cement composition of the present invention includes the cement dispersant composition of the present invention. The cement composition of the present invention comprises the cement dispersant composition of the present invention, cement and water.

  Arbitrary appropriate cement can be employ | adopted as a cement contained in the cement composition of this invention. Examples of such cements include Portland cement (ordinary, early strength, ultra-early strength, moderate heat, sulfate resistance and low alkali types thereof), various mixed cements (blast furnace cement, silica cement, fly ash cement), White Portland Cement, Alumina Cement, Super Fast Cement (1 Clinker Fast Cement, 2 Clinker Fast Cement, Magnesium Phosphate Cement), Grout Cement, Oil Well Cement, Low Exothermic Cement (Low Exothermic Blast Furnace Cement, Fly Ash Mix Low Exothermic blast furnace cement, belite high-content cement), ultra-high strength cement, cement-based solidified material, eco-cement (cement produced from one or more of municipal waste incineration ash and sewage sludge incineration ash). Furthermore, fine powders and gypsum such as blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica powder, and limestone powder may be added to the cement composition of the present invention. The cement contained in the cement composition of the present invention may be only one type or two or more types.

  The cement composition of the present invention may contain any appropriate aggregate such as fine aggregate (sand or the like) or coarse aggregate (crushed stone or the like).

  Examples of such aggregates include gravel, crushed stone, granulated slag, and recycled aggregate. Examples of such aggregates include refractory aggregates such as siliceous, clay, zircon, high alumina, silicon carbide, graphite, chromic, chromic, and magnesia.

In the cement composition of the present invention, any appropriate value can be set as the unit water amount per 1 m ³ , the amount of cement used, and the water / cement ratio. Such values, preferably, unit water is ^{100kg / m 3 ~185kg / m 3} , the amount of cement used is ^{250kg / m 3 ~800kg / m 3} , water / cement ratio (mass ratio) = is 0.1 to 0.7, more preferably, a unit water amount is ^{120kg / m 3 ~175kg / m 3} , the amount of cement used is ^{270kg / m 3 ~800kg / m 3} , water / cement ratio ( (Mass ratio) = 0.12 to 0.65. As described above, the cement composition of the present invention can be widely used from poor blending to rich blending, and can be used for both high-strength concrete with a large amount of unit cement and poor blended concrete with a unit cement amount of 300 kg / m ³ or less. It is valid.

  As a content ratio of the polycarboxylic acid copolymer contained in the cement dispersant composition of the present invention in the cement composition of the present invention, any appropriate content ratio can be adopted depending on the purpose. As such a content ratio, when used for mortar or concrete using hydraulic cement, the content of the polycarboxylic acid-based copolymer contained in the cement dispersant composition of the present invention with respect to 100 parts by mass of cement As a ratio, Preferably it is 0.01 mass part-10 mass parts, More preferably, it is 0.02 mass part-5 mass parts, More preferably, it is 0.05 mass part-3 mass parts. By setting it as such a content rate, various favorable effects, such as reduction of unit water amount, an increase in intensity | strength, and an improvement in durability, are brought about. When the content ratio is less than 0.01 parts by mass, sufficient performance may not be exhibited. When the content ratio exceeds 10 parts by mass, the effect that can be achieved substantially reaches its peak and also from the economical aspect. May be disadvantageous.

  As a content ratio of the cement dispersant composition of the present invention in the cement composition of the present invention, any appropriate content ratio can be adopted depending on the purpose. As such a content rate, as a content rate of the cement dispersant composition of this invention with respect to 100 mass parts of cement, Preferably it is 0.01 mass part-10 mass parts, More preferably, it is 0.05 mass part-8 mass parts. It is a mass part, More preferably, it is 0.1 mass part-5 mass parts. When the content ratio is less than 0.01 parts by mass, sufficient performance may not be exhibited. When the content ratio exceeds 10 parts by mass, the effect that can be achieved substantially reaches its peak and also from the economical aspect. May be disadvantageous.

  The cement composition of the present invention can be effective for ready-mixed concrete, concrete for concrete secondary products, concrete for centrifugal molding, concrete for vibration compaction, steam-cured concrete, shotcrete, and the like. The cement composition of the present invention includes medium-fluidity concrete (concrete with a slump value of 22 to 25 cm), high-fluidity concrete (concrete with a slump value of 25 cm or more and a slump flow value of 50 to 70 cm), self-filling concrete, self It can also be effective for mortar and concrete that require high fluidity, such as leveling materials.

  The cement composition of the present invention may be prepared by blending the constituent components by any appropriate method. For example, the method etc. which knead | mix a structural component in a mixer are mentioned.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these Examples. Unless otherwise specified, the term “part” means mass part, and the term “%” means mass%.

<Mass average molecular weight>
Device: Waters Alliance (2695)
Analysis software: Emper professional manufactured by Waters + GPC option Column: TSKgel Guard column SWXL (inner diameter 6.0 × 40 mm) + G4000SWXL + G3000SWXL + G2000SWXL (inner diameter 7.8 × 300 mm)
Detector: differential refractometer (RI) detector (Waters 2414)
Eluent: A solution prepared by dissolving 115.6 g of sodium acetate trihydrate in a mixed solvent of 10999 g of ion-exchanged water and 6001 g of acetonitrile, and adjusting the pH to 6.0 with acetic acid.
Flow rate: 1.0 ml / min Column / detector temperature: 40 ° C
Measurement time: 45 minutes Sample solution injection amount: 100 μl (eluent solution having a sample concentration of 0.5 mass%)
GPC standard sample: polyethylene glycol manufactured by Tosoh Corporation Mp = 300000, 200000, 107000, 44900, 30000, 20000, 11840, 6450, 4020, 1470
Calibration curve: Created by a cubic equation using the Mp value of polyethylene glycol.

<Mortar test>
(1) Mortar flow test In an atmosphere of 20 ° C. and 30 ° C., 500 g of ordinary Portland cement (manufactured by Taiheiyo Cement), 1350 g of ISO standard sand, 225 g of water in which a predetermined amount of a polycarboxylic acid copolymer and a boric acid compound are dissolved, 2% by mass of Adecanol LG-299 (manufactured by Adeka) as an antifoaming agent was put into a mortar mixer based on the total amount of the polycarboxylic acid copolymer and boric acid compound, and a mortar was prepared according to JIS R 5201. .
Based on JIS R 5201, the mortar spread diameter after giving the falling motion 15 times with a flow table was made into the initial flow value. The flow values after 30 minutes and 60 minutes were collected in a mortar container after flow measurement, stored at a predetermined temperature for a predetermined time, and then measured again according to JIS R 5201.
(2) Compressive strength test The mortar after the flow measurement is filled into a container for preparing a strength test specimen having a diameter of 5 cm and a height of 10 cm, and the surface is covered with a PET film for preventing drying, and at a predetermined temperature for 1 day and 7 days. The compression strength of the specimen prepared by storage was measured using a universal testing machine AG-25TD (manufactured by Shimadzu Corporation).

[Production Example 1]: Polycarboxylic acid copolymer (1)
In a glass reaction vessel equipped with a thermometer, a stirrer, a dripping device, a nitrogen introduction tube, and a reflux condenser, 246.6 g of water and 574.3 g of an ethylene oxide 50 mol adduct of 3-methyl-3-buten-1-ol. Then, 1.0 g of acrylic acid was charged, the inside of the reaction vessel was purged with nitrogen under stirring, and the temperature was raised to 58 ° C. in a nitrogen atmosphere, and then 25.4 g of 2% hydrogen peroxide water was added. After the temperature was stabilized at 58 ° C., an aqueous solution in which 34.7 g of acrylic acid was dissolved in 8.7 g of water was added dropwise over 3 hours. At the same time that the acrylic acid aqueous solution started to be dropped, an aqueous solution in which 0.7 g of L-ascorbic acid and 0.8 g of 2-mercaptopropionic acid were dissolved in 107.9 g of water was dropped over 3.5 hours. Thereafter, the temperature was continuously maintained at 58 ° C. for 1 hour to complete the polymerization reaction. After cooling, the pH was neutralized to 6 with a 30% aqueous NaOH solution.
When the GPC measurement of the obtained polycarboxylic acid-type copolymer (1) was performed, the mass mean molecular weight was 41000.

[Production Example 2]: Polycarboxylic acid copolymer (2)
In a glass reaction vessel equipped with a thermometer, a stirrer, a dripping device, a nitrogen inlet tube, and a reflux condenser, 220.8 g of water and 504.7 g of 3-methyl-3-buten-1-ol ethylene oxide 50 mol adduct Then, 4.3 g of acrylic acid was charged, the inside of the reaction vessel was purged with nitrogen under stirring, and the temperature was raised to 58 ° C. in a nitrogen atmosphere, and then 46.0 g of 2% aqueous hydrogen peroxide was added. After the temperature was stabilized at 58 ° C., an aqueous solution in which 38.7 g of acrylic acid and 62.3 g of 2-hydroxyethyl acrylate were dissolved in 23.7 g of water was added dropwise over 3 hours. At the same time as dropping of acrylic acid and aqueous 2-hydroxyethyl acrylate solution, an aqueous solution in which 1.2 g of L-ascorbic acid and 2.2 g of 2-mercaptopropionic acid were dissolved in 96.1 g of water was added over 3.5 hours. It was dripped. Thereafter, the temperature was continuously maintained at 58 ° C. for 1 hour to complete the polymerization reaction. After cooling, the pH was neutralized to 6 with a 30% aqueous NaOH solution.
When the GPC measurement of the obtained polycarboxylic acid-type copolymer (2) was performed, the mass mean molecular weight was 38000.

[Production Example 3]: Polycarboxylic acid copolymer (3)
In a glass reaction vessel equipped with a thermometer, a stirrer, a dropping device, a nitrogen inlet tube, and a reflux condenser, water 231.5 g, 3-methyl-3-buten-1-ol ethylene oxide 50 mol adduct 532.3 g Then, 7.8 g of acrylic acid was charged, the inside of the reaction vessel was purged with nitrogen under stirring, the temperature was raised to 58 ° C. in a nitrogen atmosphere, and then 44.6 g of 2% aqueous hydrogen peroxide was added. After the temperature was stabilized at 58 ° C., an aqueous solution in which 69.9 g of acrylic acid was dissolved in 17.5 g of water was added dropwise over 3 hours. At the same time when the acrylic acid aqueous solution was started to be dropped, an aqueous solution prepared by dissolving 1.2 g of L-ascorbic acid and 2.0 g of 2-mercaptopropionic acid in 93.3 g of water was dropped over 3.5 hours. Thereafter, the temperature was continuously maintained at 58 ° C. for 1 hour to complete the polymerization reaction. After cooling, the pH was neutralized to 6 with a 30% aqueous NaOH solution.
When the GPC measurement of the obtained polycarboxylic acid-type copolymer (3) was performed, the mass mean molecular weight was 37000.

[Production Example 4]: Polycarboxylic acid copolymer (4)
A glass reaction vessel equipped with a thermometer, stirrer, dropping device, nitrogen inlet tube, and reflux condenser was charged with 300 g of water, the inside of the reaction vessel was purged with nitrogen under stirring, and the temperature was raised to 80 ° C. under a nitrogen atmosphere. did. Next, a monomer aqueous solution in which 295 g of methoxypolyethylene glycol monomethacrylate (NK ester M-450G, manufactured by Shin-Nakamura Chemical Co., Ltd.), 26 g of methacrylic acid, and 0.66 g of 3-mercaptopropionic acid was dissolved in 75 g of water over 4 hours. It was dripped. At the same time as the dropping of the monomer aqueous solution, an aqueous solution prepared by dissolving 1.2 g of 2,2′-azobis (2-methylpropionamidine) dihydrochloride in 98.8 g of water was dropped over 5 hours. Thereafter, the polymerization reaction was completed by maintaining 80 ° C. for 1 hour. After cooling, the mixture was neutralized with a 30% NaOH aqueous solution until the pH reached 6.
When the GPC measurement of the obtained polycarboxylic acid-type copolymer (4) was performed, the mass mean molecular weight was 42000.

[Example 1]
A mixture of the polycarboxylic acid copolymer (1) obtained in Production Example 1 and boric acid (manufactured by Wako Pure Chemical Industries, Ltd.) at a mixing ratio shown in Table 1 was used as a cement dispersant composition. Table 1 shows the results of the mortar flow test at 20 ° C and 30 ° C, and Table 2 shows the results of the compressive strength test at 20 ° C and 30 ° C.

[Comparative Example 1]
Using the polycarboxylic acid copolymer (1) obtained in Production Example 1 as a cement dispersant composition, the results of a mortar flow test at 20 ° C. and 30 ° C. are shown in Table 1, at 20 ° C. and 30 ° C. Table 2 shows the results of the compressive strength test.

[Example 2]
The same procedure as in Example 1 was carried out except that the mixing ratio of the polycarboxylic acid copolymer (1) obtained in Production Example 1 and boric acid was changed as shown in Table 3, and at 20 ° C. and 30 ° C. The results of the mortar flow test are shown in Table 3.

Example 3
Table 3 shows the results of a mortar flow test performed at 20 ° C. and 30 ° C. in the same manner as in Example 1 except that sodium tetraborate (manufactured by Wako Pure Chemical Industries, Ltd.) was used instead of boric acid.

Example 4
Results obtained by conducting a mortar flow test at 20 ° C. and 30 ° C. in the same manner as in Example 1 except that sodium metaborate (sodium metaborate tetrahydrate, manufactured by Wako Pure Chemical Industries, Ltd.) was used instead of boric acid. Are shown in Table 3.

Example 5
A mixture of the polycarboxylic acid copolymer (2) obtained in Production Example 2 and boric acid (manufactured by Wako Pure Chemical Industries, Ltd.) at a mixing ratio shown in Table 4 was used as a cement dispersant composition. Table 4 shows the results of a mortar flow test performed at 30 ° C and 30 ° C.

Example 6
A mixture of the polycarboxylic acid copolymer (2) obtained in Production Example 2 and boric acid (manufactured by Wako Pure Chemical Industries, Ltd.) at a mixing ratio shown in Table 4 was used as a cement dispersant composition. Table 4 shows the results of a mortar flow test performed at 30 ° C and 30 ° C.

Example 7
A mixture of the polycarboxylic acid copolymer (2) obtained in Production Example 2 and boric acid (manufactured by Wako Pure Chemical Industries, Ltd.) at a mixing ratio shown in Table 4 was used as a cement dispersant composition. Table 4 shows the results of a mortar flow test performed at 30 ° C and 30 ° C.

[Comparative Example 2]
Table 4 shows the results of a mortar flow test conducted at 20 ° C. and 30 ° C. using the polycarboxylic acid copolymer (2) obtained in Production Example 2 as a cement dispersant composition.

Example 8
A mixture of the polycarboxylic acid copolymer (3) obtained in Production Example 3 and boric acid (manufactured by Wako Pure Chemical Industries) at a mixing ratio shown in Table 5 was used as a cement dispersant composition. Table 5 shows the results of mortar flow tests conducted at 30 ° C and 30 ° C.

Example 9
A mixture of the polycarboxylic acid copolymer (3) obtained in Production Example 3 and boric acid (manufactured by Wako Pure Chemical Industries) at a mixing ratio shown in Table 5 was used as a cement dispersant composition. Table 5 shows the results of mortar flow tests conducted at 30 ° C and 30 ° C.

[Comparative Example 3]
Table 5 shows the results of a mortar flow test conducted at 20 ° C. and 30 ° C. using the polycarboxylic acid copolymer (3) obtained in Production Example 3 as a cement dispersant composition.

Example 10
A mixture of the polycarboxylic acid copolymer (4) obtained in Production Example 4 and boric acid (manufactured by Wako Pure Chemical Industries) at a mixing ratio shown in Table 6 was used as a cement dispersant composition. Table 6 shows the results of the mortar flow test at 20 ° C and 30 ° C, and Table 7 shows the results of the compressive strength test at 20 ° C and 30 ° C.

Example 11
A mixture of the polycarboxylic acid copolymer (4) obtained in Production Example 4 and boric acid (manufactured by Wako Pure Chemical Industries) at a mixing ratio shown in Table 6 was used as a cement dispersant composition. Table 6 shows the results of mortar flow tests conducted at 30 ° C and 30 ° C.

[Comparative Example 4]
Using the polycarboxylic acid copolymer (4) obtained in Production Example 4 as a cement dispersant composition, the results of a mortar flow test at 20 ° C. and 30 ° C. are shown in Table 6, at 20 ° C. and 30 ° C. Table 7 shows the results of the compressive strength test.

  From Tables 1 to 7, it can be seen that the cement dispersant composition of the present invention has a high effect of suppressing the deterioration of fluidity with time at 30 ° C. and has high curability at 20 ° C.

  The cement dispersant composition of the present invention is suitably used for cement compositions such as cement paste, mortar and concrete. In particular, the cement dispersant composition of the present invention can enhance the effect of suppressing deterioration of fluidity over time in a high temperature environment of about 30 ° C. or higher, and can increase curability in a temperature environment of about 20 ° C. For example, high performance can be exhibited in an area where the daytime temperature is higher than about 30 ° C and the nighttime temperature is lowered to about 20 ° C.

Claims (3)

Derived from the structural unit (I) derived from the unsaturated polyalkylene glycol monomer (a) represented by the general formula (1) and the unsaturated carboxylic acid monomer (b) represented by the general formula (2) A polycarboxylic acid-based copolymer containing the structural unit (II) and a boric acid compound,
Cement dispersant composition.

(In General Formula (1), R ¹ and R ² are the same or different and each represents a hydrogen atom or a methyl group; R ³ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms; Represents an oxyalkylene group having 2 to 18 carbon atoms, n represents the average number of moles added of the oxyalkylene group represented by AO, n is an integer of 1 to 500, and x is an integer of 0 to 2 And y is 0 or 1.)

(In general formula (2), R ^{4 to} R ⁶ are the same or different and each represents a hydrogen atom, a methyl group, or — (CH ₂ ) _z COOM group, and — (CH ₂ ) _z COOM group represents a —COOX group. Or other — (CH ₂ ) _z COOM group may form an anhydride, z is an integer of 0 to 2, M is a hydrogen atom, alkali metal, alkaline earth metal, ammonium group, organic An ammonium group or an organic amine group is represented, and X represents a hydrogen atom, a methyl group, an ethyl group, an alkali metal, an alkaline earth metal, an ammonium group, an organic ammonium group, or an organic amine group.)   The cement dispersant according to claim 1, wherein a mass ratio of the polycarboxylic acid copolymer to the boric acid compound (polycarboxylic acid copolymer: boric acid compound) is 100: 1 to 100: 100. Composition.   A cement composition comprising the cement dispersant composition according to claim 1.