JP3980418B2 - Dispersant for hydraulic composition - Google Patents

Description

【０００７】
（ただし、式中R¹ならびにR³は、それぞれ水素原子又はメチル基を表わし、R²ならびにR⁴は、それぞれ水素原子又は炭素数１〜５のアルキル基を表わす。また、AOは炭素数２〜４のオキシアルキレン基の１種又は２種以上の混合物を表わし、２種以上の場合はブロック状に付加してもランダム状に付加してもよい。n及びmはオキシアルキレン基の平均付加モル数を示す値であり、p及びrは０又は１の数、q及びsは０又は１の数、２≦n≦50、２≦m≦50の数であり、｜m−n｜≧２である。）。
【０００８】
また、本発明は、上記本発明の水硬性組成物用分散剤を含有する水硬性組成物であって、オキシカルボン酸又はその塩を水硬性組成物に対して0.001〜0.2重量％含有する水硬性組成物に関する。
【０００９】
【発明の実施の形態】
ポリマー（イ）、ポリマー（ロ）の製造に用いられる一般式（イ）又は（ロ）で表される単量体としては、メトキシポリエチレングリコール、メトキシポリプロピレングリコール、メトキシポリブチレングリコール、メトキシポリスチレングリコール、エトキシポリエチレンポリプロピレングリコール等の片末端アルキル封鎖ポリアルキレングリコールと（メタ）アクリル酸、マレイン酸との（ハーフ）エステル化物、及び（メタ）アクリル酸、マレイン酸、（メタ）アリルアルコールへのエチレンオキシド、プロピレンオキシド付加物やアルケニルエーテルのアルキレンオキシド付加物が挙げられる。アルコキシ、特にはメトキシポリエチレングリコールと（メタ）アクリル酸とのエステル化物である。一般式（イ）、（ロ）中のR¹ならびにR³は、それぞれ水素原子が好ましい。特に、オキシアルキレン基はオキシエチレン基が好ましい。
【００１０】
一般式（イ）、（ロ）中のp及びrは０又は１の数であり、１が好ましい。また、q及びsは０又は１の数であり、０が好ましい。n及びmは、オキシアルキレン基の平均付加モル数を示す値であり、２≦n≦50、好ましくは３≦n≦40、より好ましくは５≦n≦20、２≦m≦50の数、好ましくは３≦m≦20、より好ましくは５≦m≦20であり、｜m−n｜≧２、好ましくは｜m−n｜≧５、より好ましくは｜m−n｜≧10である。n、mがこの関係を満たすことにより、セメントの種類の違いにかかわらず、安定した流動保持性、減水性を付与することができる。
【００１１】
ポリマー（イ）又はポリマー（ロ）中の全ポリマーに対する一般式（イ）又は（ロ）で表される単量体のモル比は、分散性と流動保持性の両立の観点から、１０〜９０％が好ましく、更に２０〜８０％、特に３０〜７０％が好ましい。
【００１２】
一般式（イ）、（ロ）中のR²ならびにR⁴は、それぞれ炭素数１〜３のアルキル基が好ましく、特に炭素数１のアルキル基が好ましい。
【００１３】
ポリマー（イ）及びポリマー（ロ）は、それぞれ下記一般式（ハ）で表される単量体を構成単位として含むことが好ましい。
【００１４】
【化４】

【００１５】
（ただし、式中R⁵は水素原子もしくはメチル基を表わし、R⁶は水素原子、メチル基又はCOOM²であり、COOM²はCOOM¹と無水物を形成してもよい。M¹及びM²は水素原子、一価金属、二価金属、アンモニウム基又は有機アミン基を表わす。）。
【００１６】
一般式（ハ）で表される単量体としては、（メタ）アクリル酸又はその塩、マレイン酸又はその塩や無水物が挙げられ、塩はアルカリ金属塩、アルカリ土類金属塩、アンモニウム塩、水酸基が置換されていてもよいモノ、ジ、トリアルキル（炭素数２〜８）アンモニウム塩が好ましく、より好ましくは（メタ）アクリル酸、マレイン酸、無水マレイン酸、更に好ましくは（メタ）アクリル酸又はこれらのアルカリ金属塩である。
【００１７】
一般式（ハ）で表される単量体の比率（モル比）は、スランプ保持性と減水性の観点から、一般式（イ）又は（ロ）の単量体／一般式（ハ）の単量体＝５／95〜95／５、更に20／80〜80／20、特に35／65〜65／35が好ましい。
【００１８】
本発明では、ポリマー（イ）とポリマー（ロ）の固形分重量比が、ポリマー（イ）／ポリマー（ロ）＝５／95〜95／５であることがスランプ保持性と減水性の点で好ましく、より好ましくは25／75〜75／25である。ここで、ポリマー（イ）とポリマー（ロ）のうち、アルキレンオキサイド平均付加モル数が小さい方が多くなるように用いるのが、粘性低下の点から、好ましい。
【００１９】
本発明の水硬性組成物用分散剤は、ポリマー（イ）とポリマー（ロ）とを有効分合計で50〜99.9重量％、更に75〜95重量％、特に80〜90重量％含有することが好ましい。
【００２０】
ポリマー（イ）、ポリマー（ロ）の重量平均分子量〔ゲルパーミエーションクロマトグラフィー法、ポリエチレングリコール換算、カラム：G4000PWXL ＋ G2500PWXL（東ソー（株）製）、溶離液：0.2Mリン酸緩衝液／アセトニトリル＝７／３（体積比）〕は、それぞれ10,000〜200,000が好ましく、20,000〜100,000が特に好ましい。
【００２１】
なお、ポリマー（イ）とポリマー（ロ）は、構成単量体として、アクリロニトリル、（メタ）アクリルアミド、スチレン、（メタ）アクリル酸アルキル（水酸基を有していてもよい炭素数１〜12のもの）エステル、スチレンスルホン酸等の共重合可能な単量体を併用してもよい。
【００２２】
本発明に用いられるオキシカルボン酸又はその塩としては、炭素数２〜８のものが好ましく、カルボキシル基は１〜３個が好ましい。例えば、グルコヘプトン酸、グルコン酸、ガラクトン酸、クエン酸、酒石酸、リンゴ酸、グリコール酸、乳酸、α−オキシ酪酸及びこれらの塩が挙げられ、塩としてはナトリウム塩やカリウム塩などの無機塩もしくは、有機塩が挙げられる。特に好ましくはグルコン酸、クエン酸及びこれらの塩（なかでもナトリウム塩）である。
【００２３】
本発明の水硬性組成物用分散剤は、オキシカルボン酸又はその塩を、硬化時間と流動保持性の点で、固形分で５〜40重量％、更に５〜25重量％、特に10〜20重量％含有することが好ましい。
【００２４】
また、ポリマー（イ）及びポリマー（ロ）とオキシカルボン酸又はその塩の有効分の重量比は、〔ポリマー（イ）＋ポリマー（ロ）〕／（オキシカルボン酸又はその塩）＝60／40〜95／５、更に75／25〜95／５、特に80／20〜90／10が好ましい。
【００２５】
本発明の水硬性組成物用分散剤は、コンクリートの配合条件によって異なるが、スランプ保持性、凝結遅延、硬化不良等のバランスを考慮すると、セメントに対して固形分換算で0.1〜3.0重量％、更に0.3〜2.5重量％、特に0.5〜2.0重量％添加することが好ましい。
【００２６】
オキシカルボン酸又はその塩を、セメントの種類に依存しない顕著な流動保持性と減水性の発現と硬化遅延を３時間以内に抑える観点から、水硬性組成物に対して0.001〜0.2重量％、更に0.003〜0.15重量％、特に0.01〜0.1重量％を含有するように添加することが好ましい。
【００２７】
本発明の水硬性組成物用分散剤の使用方法は、一般の水硬性組成物用分散剤と同様であり、コンクリート混練り時に直接添加してもよく、又は混練り水にあらかじめ希釈させておき添加してもよい。ここで、水硬性組成物用分散剤以外のコンクリート成分は、セメント、例えば普通ポルトランドセメント、低発熱ポルトランドセメント、早強ポルトランドセメント、中庸熱ポルトランドセメント、高炉セメント、シリカフューム混セメント等、細骨材、粗骨材、混和材、例えばシリカフューム、スラグ粉末、炭酸カルシウム粉末、膨張材、フライアッシュ等を挙げることができる。また、本発明の分散剤以外の分散剤、減水剤、空気連行剤、消泡剤等も配合することは可能である。
【００２８】
本発明の水硬性組成物用分散剤とセメントと水とを含有する水硬性スラリーは、セメントの種類にかかわらず同等の優れた流動性と流動保持性が得られる。これは、オキシカルボン酸がセメント表面に吸着することで、セメントの水和反応を制御し、流動保持性を改善するためと考えられる。
【００２９】
本発明の水硬性組成物用分散剤は、普通ポルトランドセメント、低発熱セメント、中庸熱セメント、高炉Ｂ種セメント等、水硬性粉体の種類に関わらず、優れた流動性ならびに流動保持性を、水硬性組成物に付与することができる。なかでも、セメントとして高炉セメント、低発熱ポルトランドセメント、中庸熱ポルトランドセメントを使用した場合は、分散保持性の向上度合いがより顕著となる。また、本発明の水硬性組成物用分散剤は、凝結遅延を３時間以内に制御することが可能である。
【００３０】
【実施例】
＜製造例＞
温度計、攪拌機、滴下漏斗、窒素同入管及び還流冷却器を備えたガラス製反応容器に水500部（重量基準、以下同様）を仕込み、攪拌下に反応容器内を窒素置換し、窒素雰囲気下で80℃まで加熱した。次に、メトシキポリエチレングリコールモノメタクリレート〔エチレンオキシドの平均付加モル数（以下、EOpと表記する）５〕240部、メタクリル酸120部、水43.2部、及び連鎖移動剤として２−メルカプトエタノール3.3部を混合したモノマー水溶液ならびに、10％過硫酸アンモニウム水溶液50部を４時間で滴下し、滴下終了後、さらに10％過硫酸アンモニウム水溶液15部を１時間で滴下した。その後、１時間引き続いて80℃を維持し、重合反応を完結させ、重量平均分子量38000の共重合体を含有する水溶液A-1を得た。この水溶液をそのまま５重量％濃度に希釈した水溶液のpHは6.0（20℃）であった。
【００３１】
上記と同様な方法で共重合を行ない、表１に示す共重合体含有水溶液A-2〜A-11及びC-1〜C-2を得た。ただし、A-11としては、メトキシポリエチレングリコールアルケニルエーテルと無水マレイン酸との共重合体を、特開平5-345647号(4)頁の製造例１の方法に準じて製造した。また、各水溶液は、共重合体濃度が固形分で20重量％になるように水分調整を行なった。なお、C-1及びC-2は比較例である。
【００３２】
【表１】

【００３３】
＜オキシカルボン酸＞
オキシカルボン酸として、以下の表２に示すものを使用した。D-3は比較化合物である。
【００３４】
【表２】

【００３５】
＜コンクリート試験＞
上記成分を表４に示す組成で組み合わせて水硬性組成物用分散剤を調製し、表３に示すコンクリート配合条件に対してコンクリート試験を行なった。コンクリートの練り混ぜは、60リットル強制二軸ミキサー（IHI社製）を使用した。粗骨材、細骨材、セメント、分散剤を含んだ混練り水を加え、90秒練り混ぜを行ない排出したフレッシュコンクリートについては、日本工業規格（スランプ：JIS A 1101）に準拠してスランプ値を測定した。また、AE剤（エマール27C、花王株式会社製）を用いて、空気量を4.5体積％にした。試験は20℃に温度管理された実験室で行なった。また、分散保持性の尺度として、排出後各時間のスランプ値に対する初期のスランプ値の百分率を保持率とした。この数値が大きいほど分散保持性が良好とする。結果を表４に示す。本発明の水硬性組成物用分散剤を用いた試験No.１〜10ではセメントの種類によらず優れた流動性と流動保持性が得られた。
【００３６】
【表３】

【００３７】
・W：水道水
・C：セメント
・OPC：普通ポルトランドセメント（密度：3.16g/cm³）
・BB：高炉B種セメント（密度：3.04g/cm³）
・LPC：低熱ポルトランドセメント（密度：3.22g/cm³）
・S：千葉県君津産山砂（密度：2.62g/cm³）
・G：高知県鳥形産石灰砕石（密度：2.72g/cm³）
【００３８】
【表４】

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cement dispersant. More specifically, for hydraulic compositions that exhibit excellent fluidity, fluidity retention, material separation resistance, and versatility with respect to concrete production conditions for hydraulic compositions such as cement paste, mortar and concrete It relates to additives.
[0002]
[Prior art]
Conventionally, lignin sulfonate, naphthalene sulfonate formalin condensate, melamine sulfonate formalin condensate, and polycarboxylic acid dispersants have been used as dispersants for hydraulic compositions. Due to recent building demands, materials for producing concrete have been diversified. For example, the types of cement include ordinary Portland cement, low heat Portland cement, early strength Portland cement, moderately hot Portland cement, blast furnace cement, silica fume mixed cement, etc. There is also a large range in the amount of ions eluted in the slurry using these.
[0003]
And by changing the type of cement, the above dispersant is affected by fluctuations in the amount of ions eluting in the system, and the amount added is equal to the initial slump value when used for ordinary cement. It will decrease and the fluidity will deteriorate. In addition, the required amount of dispersant varies depending on the type of cement, making it difficult to handle. Japanese Patent Application Laid-Open No. 9-286645 discloses that a copolymer using a short chain and a long chain polyethylene glycol (meth) acrylate is used as a cement admixture. It is insufficient as a measure for obtaining retention and water reduction. In addition, oxycarboxylic acid is used in JP-A-10-7445 as a curing retarder for concrete and the like.
[0004]
[Problems to be solved by the invention]
An object of the present invention is to obtain a dispersant for a hydraulic composition that is less affected by the difference in the type of cement and that can provide stable fluidity retention and water reduction.
[0005]
[Means for Solving the Problems]
The present invention relates to a polymer comprising a monomer represented by the following general formula (A) as a structural unit (hereinafter referred to as polymer (A)) and a monomer represented by the following general formula (B): The present invention relates to a dispersant for a hydraulic composition containing a polymer (hereinafter referred to as polymer (b)) as a structural unit and oxycarboxylic acid or a salt thereof.
[0006]
[Chemical 3]

[0007]
(In the formula, R ¹ and R ³ each represent a hydrogen atom or a methyl group, R ² and R ⁴ each represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. AO represents 2 carbon atoms. Represents one or a mixture of two or more oxyalkylene groups of -4, and in the case of two or more types, they may be added in blocks or randomly, where n and m are average additions of oxyalkylene groups P and r are numbers of 0 or 1, q and s are numbers of 0 or 1, 2 ≦ n ≦ 50, 2 ≦ m ≦ 50, and | m−n | ≧ 2).
[0008]
The present invention also provides a hydraulic composition containing the above-described dispersant for a hydraulic composition of the present invention, wherein the oxycarboxylic acid or a salt thereof is contained in an amount of 0.001 to 0.2% by weight based on the hydraulic composition. It relates to a hard composition.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
As the monomer represented by the general formula (I) or (B) used for the production of the polymer (I) and the polymer (B), methoxypolyethylene glycol, methoxypolypropylene glycol, methoxypolybutylene glycol, methoxypolystyrene glycol, (Half) esterified products of (terminated) alkyl-blocked polyalkylene glycols such as ethoxypolyethylenepolypropyleneglycol with (meth) acrylic acid and maleic acid, and ethylene oxide and propylene to (meth) acrylic acid, maleic acid and (meth) allyl alcohol Examples thereof include oxide adducts and alkylene oxide adducts of alkenyl ethers. It is an esterified product of alkoxy, particularly methoxypolyethylene glycol and (meth) acrylic acid. R ¹ and R ³ in the general formulas (a) and (b) are each preferably a hydrogen atom. In particular, the oxyalkylene group is preferably an oxyethylene group.
[0010]
In the general formulas (a) and (b), p and r are 0 or 1, and 1 is preferable. Moreover, q and s are the numbers of 0 or 1, and 0 is preferable. n and m are values indicating the average number of added moles of the oxyalkylene group, 2 ≦ n ≦ 50, preferably 3 ≦ n ≦ 40, more preferably 5 ≦ n ≦ 20, 2 ≦ m ≦ 50, Preferably 3 ≦ m ≦ 20, more preferably 5 ≦ m ≦ 20, and | m−n | ≧ 2, preferably | m−n | ≧ 5, more preferably | m−n | ≧ 10. When n and m satisfy this relationship, stable fluidity retention and water reduction can be imparted regardless of the type of cement.
[0011]
The molar ratio of the monomer represented by the general formula (A) or (B) to the whole polymer in the polymer (A) or the polymer (B) is 10 to 90 from the viewpoint of compatibility between dispersibility and fluidity retention. %, More preferably 20 to 80%, and particularly preferably 30 to 70%.
[0012]
R ² and R ^{4 in} general formulas (a) and (b) are each preferably an alkyl group having 1 to 3 carbon atoms, and particularly preferably an alkyl group having 1 carbon atom.
[0013]
The polymer (a) and the polymer (b) preferably each contain a monomer represented by the following general formula (c) as a structural unit.
[0014]
[Formula 4]

[0015]
(However, in the formula, R ⁵ represents a hydrogen atom or a methyl group, R ⁶ represents a hydrogen atom, a methyl group, or COOM ² , and COOM ² may form an anhydride with COOM ^1. M ¹ and M ² Represents a hydrogen atom, a monovalent metal, a divalent metal, an ammonium group or an organic amine group.
[0016]
Examples of the monomer represented by the general formula (c) include (meth) acrylic acid or a salt thereof, maleic acid or a salt or anhydride thereof, and the salt is an alkali metal salt, an alkaline earth metal salt, or an ammonium salt. , Mono-, di-, and trialkyl (2 to 8 carbon atoms) ammonium salts optionally substituted with a hydroxyl group are preferable, (meth) acrylic acid, maleic acid, maleic anhydride, more preferably (meth) acrylic. An acid or an alkali metal salt thereof.
[0017]
The ratio (molar ratio) of the monomer represented by the general formula (C) is the monomer of the general formula (A) or (B) / the general formula (C) from the viewpoint of slump retention and water reduction. Monomer = 5/95 to 95/5, more preferably 20/80 to 80/20, and particularly preferably 35/65 to 65/35.
[0018]
In the present invention, the solid content weight ratio of the polymer (b) to the polymer (b) is polymer (b) / polymer (b) = 5/95 to 95/5 in terms of slump retention and water reduction. More preferably, it is 25/75 to 75/25. Here, it is preferable from the point of viscosity fall to use so that the one where an alkylene oxide average addition mole number is small increases among a polymer (a) and a polymer (b).
[0019]
The dispersant for a hydraulic composition of the present invention may contain 50 to 99.9% by weight, further 75 to 95% by weight, particularly 80 to 90% by weight, in total of polymer (A) and polymer (B). preferable.
[0020]
Polymer (I), weight average molecular weight of polymer (B) [gel permeation chromatography method, converted to polyethylene glycol, column: G4000PWXL + G2500PWXL (manufactured by Tosoh Corporation), eluent: 0.2 M phosphate buffer / acetonitrile = 7/3 (volume ratio)] is preferably 10,000 to 200,000, particularly preferably 20,000 to 100,000.
[0021]
In addition, the polymer (b) and the polymer (b) are acrylonitrile, (meth) acrylamide, styrene, alkyl (meth) acrylate (having 1 to 12 carbon atoms which may have a hydroxyl group) as constituent monomers. ) A copolymerizable monomer such as ester or styrenesulfonic acid may be used in combination.
[0022]
As oxycarboxylic acid or its salt used for this invention, a C2-C8 thing is preferable and a carboxyl group has 1-3 preferable. For example, glucoheptonic acid, gluconic acid, galactonic acid, citric acid, tartaric acid, malic acid, glycolic acid, lactic acid, α-oxybutyric acid and salts thereof may be mentioned, and the salt may be an inorganic salt such as sodium salt or potassium salt, Organic salts are mentioned. Particularly preferred are gluconic acid, citric acid and salts thereof (especially sodium salts).
[0023]
The dispersant for a hydraulic composition of the present invention is an oxycarboxylic acid or a salt thereof having a solid content of 5 to 40% by weight, more preferably 5 to 25% by weight, particularly 10 to 20% in terms of curing time and fluidity retention. It is preferable to contain by weight.
[0024]
The weight ratio of the polymer (a) and the effective amount of the polymer (b) and the oxycarboxylic acid or salt thereof is [polymer (a) + polymer (b)] / (oxycarboxylic acid or salt thereof) = 60/40 ~ 95/5, more preferably 75/25 to 95/5, and particularly preferably 80/20 to 90/10.
[0025]
The dispersant for the hydraulic composition of the present invention varies depending on the mixing conditions of the concrete, but considering the balance of slump retention, setting delay, poor curing, etc., 0.1 to 3.0% by weight in terms of solid content with respect to cement, Further, it is preferable to add 0.3 to 2.5% by weight, particularly 0.5 to 2.0% by weight.
[0026]
Oxycarboxylic acid or a salt thereof is 0.001 to 0.2% by weight with respect to the hydraulic composition from the viewpoint of suppressing remarkable fluidity retention and water-reducing expression independent of the cement type, and delaying curing within 3 hours. It is preferable to add so as to contain 0.003 to 0.15% by weight, particularly 0.01 to 0.1% by weight.
[0027]
The method of using the dispersing agent for hydraulic composition of the present invention is the same as that of a general dispersing agent for hydraulic composition, and may be added directly at the time of kneading concrete, or previously diluted in kneading water. It may be added. Here, concrete components other than the dispersant for the hydraulic composition are cement, for example, ordinary Portland cement, low heat Portland cement, early strong Portland cement, moderately hot Portland cement, blast furnace cement, silica fume blended cement, fine aggregate, Coarse aggregates and admixtures such as silica fume, slag powder, calcium carbonate powder, expansion material, fly ash and the like can be mentioned. Moreover, it is possible to mix | blend a dispersing agent other than the dispersing agent of this invention, a water reducing agent, an air entraining agent, an antifoamer, etc.
[0028]
The hydraulic slurry containing the dispersant for hydraulic composition of the present invention, cement, and water can provide the same excellent fluidity and fluidity retention regardless of the type of cement. This is considered to be because the oxycarboxylic acid is adsorbed on the cement surface, thereby controlling the hydration reaction of the cement and improving the fluidity retention.
[0029]
The dispersant for a hydraulic composition of the present invention has excellent fluidity and fluidity retention regardless of the type of hydraulic powder, such as ordinary Portland cement, low heat generation cement, medium heat cement, blast furnace type B cement, etc. It can be applied to the hydraulic composition. In particular, when blast furnace cement, low heat generation Portland cement, or moderately hot Portland cement is used as the cement, the degree of improvement in dispersion retention becomes more remarkable. Moreover, the dispersion agent for hydraulic compositions of the present invention can control the setting delay within 3 hours.
[0030]
【Example】
<Production example>
A glass reaction vessel equipped with a thermometer, stirrer, dropping funnel, nitrogen inlet tube and reflux condenser was charged with 500 parts of water (weight basis, the same applies hereinafter), and the inside of the reaction vessel was purged with nitrogen under stirring. And heated to 80 ° C. Next, methoxy polyethylene glycol monomethacrylate [average added mole number of ethylene oxide (hereinafter referred to as EOP) 5] 240 parts, 120 parts of methacrylic acid, 43.2 parts of water, and 3.3 parts of 2-mercaptoethanol as a chain transfer agent. The mixed monomer aqueous solution and 50 parts of a 10% ammonium persulfate aqueous solution were added dropwise over 4 hours. After completion of the addition, 15 parts of a 10% ammonium persulfate aqueous solution was added dropwise over 1 hour. Thereafter, the temperature was maintained at 80 ° C. for 1 hour to complete the polymerization reaction, and an aqueous solution A-1 containing a copolymer having a weight average molecular weight of 38000 was obtained. The pH of an aqueous solution obtained by diluting this aqueous solution as it was to a concentration of 5% by weight was 6.0 (20 ° C.).
[0031]
Copolymerization was performed in the same manner as above to obtain copolymer-containing aqueous solutions A-2 to A-11 and C-1 to C-2 shown in Table 1. However, as A-11, a copolymer of methoxypolyethylene glycol alkenyl ether and maleic anhydride was produced according to the method of Production Example 1 on page 4 of JP-A-5-345647. In addition, each aqueous solution was adjusted in water so that the copolymer concentration was 20% by weight in terms of solid content. C-1 and C-2 are comparative examples.
[0032]
[Table 1]

[0033]
<Oxycarboxylic acid>
As the oxycarboxylic acid, those shown in Table 2 below were used. D-3 is a comparative compound.
[0034]
[Table 2]

[0035]
<Concrete test>
The said component was combined with the composition shown in Table 4, the dispersing agent for hydraulic compositions was prepared, and the concrete test was done with respect to the concrete mixing conditions shown in Table 3. For mixing the concrete, a 60-liter forced biaxial mixer (manufactured by IHI) was used. For fresh concrete that has been mixed for 90 seconds after adding kneaded water containing coarse aggregate, fine aggregate, cement, and dispersant, the slump value conforms to the Japanese Industrial Standard (Slump: JIS A 1101). Was measured. In addition, the air amount was set to 4.5% by volume using an AE agent (Emar 27C, manufactured by Kao Corporation). The test was performed in a laboratory controlled at 20 ° C. In addition, as a measure of dispersion retention, the retention rate was the percentage of the initial slump value with respect to the slump value at each time after discharge. The larger this value, the better the dispersion retention. The results are shown in Table 4. In Test Nos. 1 to 10 using the dispersant for hydraulic composition of the present invention, excellent fluidity and fluid retention were obtained regardless of the type of cement.
[0036]
[Table 3]

[0037]
・ W: Tap water ・ C: Cement ・ OPC: Ordinary Portland cement (Density: 3.16 g / cm ³ )
・ BB: Blast furnace type B cement (density: 3.04g / cm ³ )
・ LPC: Low heat Portland cement (density: 3.22 g / cm ³ )
・ S: Mountain sand from Kimitsu, Chiba (density: 2.62 g / cm ³ )
・ G: Limestone produced in Torigata, Kochi Prefecture (density: 2.72 g / cm ³ )
[0038]
[Table 4]

Claims (7)

The monomer represented by the following general formula (A) and the monomer represented by the following general formula (C) are represented by the monomer represented by the general formula (A) / general formula (C). in a molar ratio of monomer = 35 / 65-65 / 35, which is a polymer containing a structural unit [hereinafter, polymer (a) and is denoted] and a monomer represented by the following general formula (b) the following general formula and a monomer represented by (c), the general formula monomer / general formula represented by (b) (c) represented by monomer = 35 / 65-65 / 35 Containing a polymer (hereinafter referred to as polymer (b)) as a structural unit in a molar ratio, and one or more oxycarboxylic acids or salts thereof selected from the group consisting of gluconic acid, citric acid and salts thereof and, the solid content weight ratio of the polymer (a) and polymer (b) is a polymer (a) / polymer (b) = 5/95 to 95/5, [polymer B) + polymer (b)] / (oxycarboxylic acid or a solid weight ratio of 75 / 25-95 / 5 der Ru hydraulic composition dispersant salt thereof).

(In the formula, R ¹ and R ³ each represent a hydrogen atom or a methyl group, R ² and R ⁴ each represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. AO represents 2 carbon atoms. Represents one or a mixture of two or more oxyalkylene groups of -4, and in the case of two or more types, they may be added in blocks or randomly, where n and m are average additions of oxyalkylene groups P and r are numbers of 1; q and s are numbers of 0 or 1; 5 ≦ n ≦ 20 and 5 ≦ m ≦ 50; and | m−n | ≧ 4 is there.)

(However, in the formula, R ⁵ represents a hydrogen atom or a methyl group, R ⁶ represents a hydrogen atom, a methyl group, or COOM ² , and COOM ² may form an anhydride with COOM ^1. M ¹ and M ² Represents a hydrogen atom, a monovalent metal, a divalent metal, an ammonium group or an organic amine group.) The dispersing agent for hydraulic compositions according to claim 1, containing 5 to 25 % by weight of oxycarboxylic acid or a salt thereof in solid content. The dispersant for a hydraulic composition according to claim 1 or 2 , which is used for a hydraulic composition containing a cement selected from low exothermic cement and blast furnace type B cement. Cement, water, and a hydraulic composition containing any one of claims hydraulic composition dispersant according to claim 1 to 3, a hydroxycarboxylic acid or a salt thereof with respect to the hydraulic composition 0.001 Hydraulic composition containing ˜0.2% by weight. The hydraulic composition according to claim 4, wherein the cement is a cement selected from a low heat generation cement and a blast furnace type B cement. The hydraulic composition according to claim 4 or 5 , wherein the curing delay is within 3 hours. It is a manufacturing method of the hydraulic composition which manufactures the hydraulic composition containing water and hydraulic powder using the dispersing agent for hydraulic compositions of any one of Claims 1-3 , A hydraulic composition having a curing delay of 3 hours or less is used by using the dispersant so that the oxycarboxylic acid or a salt thereof in the dispersant is 0.001 to 0.2% by weight with respect to the hydraulic composition. A method for producing a hydraulic composition.