Dispersant composition for hydraulic composition and hydraulic composition

Abstract

To provide a dispersant which exhibits good performance even for a hydraulic composition containing blast furnace slag and / or fly ash.SOLUTION: There is provided a dispersant composition for a hydraulic composition which comprises cement, a hydraulic powder containing blast furnace slag and / or fly ash, and component (A) and component (B) composed of mutually different specific copolymers. In addition, there is provided a hydraulic composition comprising cement, a hydraulic powder containing blast furnace slag and / or fly ash, water and the dispersant composition for a hydraulic composition.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a dispersant composition for a hydraulic composition and a hydraulic composition. [Background technology]

[0002] 2. Description of the Related Art Admixtures containing acrylic acid-based polyethylene glycol ethers for imparting fluidity to hydraulic compositions such as concrete are known.

[0003] For example, Patent Document 1 discloses a dispersant for a clay-containing hydraulic composition, which contains three types of acrylic acid copolymers and an acrylic acid copolymer to which ethylene oxide is added via an ether bond. In addition, Patent Document 2 states that 1 -O-(A 1 O) n1 -R 2 (In the formula, R 1 represents an alkenyl group having 2 to 5 carbon atoms. 1 O is the same or different and represents an oxyalkylene group having 2 to 18 carbon atoms. n1 is the average number of moles of the oxyalkylene group added and represents a number of 1 to 200. R 2 represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms.), a structural unit derived from an unsaturated monocarboxylic acid monomer (II), and a structural unit derived from an unsaturated dicarboxylic acid monomer (III) are disclosed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2022-18729 A [Patent Document 2] JP 2017-65989 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, there has been no disclosure to date of improvements in shape retention and vibration elongation when such a dispersant is used. [Means for solving the problem]

[0006] The present invention relates to a dispersant composition for hydraulic compositions containing hydraulic powder including cement and blast furnace slag and / or fly ash, the dispersant composition for hydraulic compositions containing the following components (A) and (B): (A) Component: General formula (a1) [ka] [In the formula, R 1a represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. a represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), ammonium, or an organic ammonium. A structural unit (A1) represented by the formula: General formula (a2) [ka] [In the formula, R 2a represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. X represents an alkylene group having 1 to 4 carbon atoms. na represents the average number of moles added of 20 or more and less than 150. R 3a represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or a hydrocarbon group having 1 to 4 carbon atoms which may contain a heteroatom.] A structural unit (A2) represented by the formula: and optionally having the general formula (a3) [ka] [In the formula, R 4a R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. 5arepresents an alkyl group having 1 to 18 carbon atoms or a hydrocarbon group having 1 to 4 carbon atoms which may contain a heteroatom.] A copolymer having a structural unit (A3) represented by the following formula: Copolymer A, in which the proportion of the structural unit (A1) relative to the total of the structural units (A1), (A2), and (A3) is 3% by mass or more and less than 10% by mass. (B) Ingredients: General formula (b1) [ka] [In the formula, R 1b represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. b represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), ammonium, or an organic ammonium. A structural unit (B1) represented by the formula: General formula (b2) [ka] [In the formula, R 2b represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. nb represents the average number of moles added of 10 or more and less than 80. R 3b represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms. A copolymer having a structural unit (B2) represented by the following formula: Copolymer B, in which the proportion of the structural unit (B1) relative to the total of the structural units (B1) and (B2) is 5% by mass or more and less than 20% by mass. The present invention also relates to a hydraulic composition comprising a hydraulic powder containing cement, blast furnace slag and / or fly ash, water, and the above-mentioned dispersant composition for hydraulic compositions. Effect of the Invention

[0007] According to the present invention, it is possible to provide a dispersant composition for hydraulic compositions which realizes both good shape retention and vibration elongation and can be used even in hydraulic compositions containing blast furnace slag and / or fly ash. Moreover, according to the present invention, a hydraulic composition containing the dispersant for hydraulic compositions can be provided. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] The dispersant composition for hydraulic compositions of the present invention contains the following components (A) and (B): (A) Component: General formula (A1) [ka] [In the formula, R 1a represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. a represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), ammonium, or an organic ammonium. A structural unit (A1) represented by the formula: General formula (A2) [ka] [In the formula, R 2a represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. X represents an alkylene group having 1 to 4 carbon atoms. na represents the average number of moles added of 20 or more and less than 150. R 3a represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or a hydrocarbon group having 1 to 4 carbon atoms which may contain a heteroatom.] A structural unit (A2) represented by the formula: and optionally having the general formula (a3) [ka] [In the formula, R 4a R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. 5a represents an alkyl group having 1 to 18 carbon atoms or a hydrocarbon group having 1 to 4 carbon atoms which may contain a heteroatom.] A copolymer having a structural unit (A3) represented by the following formula: Copolymer A, in which the proportion of the structural unit (A1) relative to the total of the structural units (A1), (A2), and (A3) is 3% by mass or more and less than 10% by mass. (B) Ingredients: General formula (b1) [ka] [In the formula, R 1b represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. b represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), ammonium, or an organic ammonium. A structural unit (B1) represented by the formula: General formula (b2) [ka] [In the formula, R 2b represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. nb represents the average number of moles added of 10 or more and less than 80. R 3b represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms. A copolymer B having a structural unit (B2) represented by the following formula: Copolymer B, in which the proportion of the structural unit (B1) relative to the total of the structural units (B1) and (B2) is 5% by mass or more and less than 20% by mass.

[0009] First, the components (A) and (B) will be described. The component (A) is represented by the general formula (a1) [ka] [In the formula, R 1a represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. a represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), ammonium, or an organic ammonium. A structural unit (A1) represented by general formula (a2) [ka] [In the formula, R 2a represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. X represents an alkylene group having 1 to 4 carbon atoms. na represents the average number of moles added of 20 or more and less than 150. R 3a represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or a hydrocarbon group having 1 to 4 carbon atoms which may contain a heteroatom.] and optionally a structural unit (A2) represented by general formula (a3) [ka] [In the formula, R 4a R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. 5a represents an alkyl group having 1 to 18 carbon atoms or a hydrocarbon group having 1 to 4 carbon atoms which may contain a heteroatom.] Copolymer A has a structural unit (A3) represented by the following formula:

[0010] The structural unit (A1) represented by general formula (a1) can be introduced into the copolymer A by using a monomer represented by general formula (a1') as the raw material. [ka] [In the formula, R 1a represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. a represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), ammonium, or an organic ammonium.

[0011] M in general formula (a1') a Examples of the cation include a hydrogen atom, alkali metals such as lithium, sodium, and potassium, and alkaline earth metals such as magnesium and calcium. In view of good dispersibility, a hydrogen atom or an alkali metal is preferred.

[0012] R in general formula (a1') 1aExamples of the alkyl group include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, etc. In terms of obtaining the copolymer in good yield, a hydrogen atom and a methyl group are preferred, and a hydrogen atom is more preferred.

[0013] The structural unit (A2) represented by general formula (a2) can be introduced into copolymer A by using a monomer represented by general formula (a2') as the raw material. [ka] [In the formula, R 2a represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. X represents an alkylene group having 1 to 4 carbon atoms. na represents the average number of moles added of 20 or more and less than 150. R 3a represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or a hydrocarbon group having 1 to 4 carbon atoms which may contain a heteroatom.]

[0014] R in general formula (a2') 2a Specific examples of the alkyl group include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, etc. In terms of obtaining the copolymer in good yield, a hydrogen atom and a methyl group are preferred, and a methyl group is more preferred.

[0015] X in general formula (a2') a Examples of alkylene groups include a methylene group, an ethylene group, a propylene group, a butylene group, etc. In terms of good shape retention and vibration properties, an alkylene group is preferred, and an ethylene group is more preferred.

[0016] The average number of moles na added of the general formula (a2') is preferably 20 or more, more preferably 40 or more, and even more preferably 50 or more in terms of good vibration property, and is preferably less than 150, more preferably less than 100, and even more preferably less than 80. In the present application, two or more types of monomers of the general formula (a2') may be used. When two or more types of monomers are used, the average number of moles added na is defined as the average number of moles added calculated according to the molar ratio thereof.

[0017] R in general formula (a2') 3a Specific examples of the alkyl group include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, a hexyl group, a 2-ethylhexyl group, a cyclohexyl group, an octyl group, a cyclooctyl group, a decyl group, a dodecyl group, a tetradecyl group, a hexadecyl group, an octadecyl group, etc. In terms of good dispersibility, a hydrogen atom and a methyl group are preferred, and a hydrogen atom is more preferred.

[0018] The structural unit (A3) represented by general formula (a3) ​​can be introduced into copolymer A by using a monomer represented by general formula (a3') as the raw material. [ka] [In the formula, R 4a R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. 5a represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or a hydrocarbon group having 1 to 4 carbon atoms which may contain a heteroatom.]

[0019] R in general formula (a3') 4a Specific examples of the alkyl group include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, etc. In terms of obtaining a copolymer in good yield, a hydrogen atom and a methyl group are preferred.

[0020] R in general formula (a3') 5a Specific examples of the alkyl group include methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, hexyl, 2-ethylhexyl, cyclohexyl, octyl, cyclooctyl, decyl, dodecyl, tetradecyl, hexadecyl, octadecyl, etc. The methyl or 2-ethylhexyl group is preferred because of its good fluidity retention.

[0021] Even if the structural unit (A3) is not contained in the copolymer A, good shape retention and vibration imparting properties are sufficiently exhibited.

[0022] The proportion of the structural unit (A1) relative to the total of the structural units (A1), (A2), and (A3) is preferably at least 3 mass%, more preferably at least 4 mass%, and even more preferably at least 5 mass%, in terms of good shape retention and vibration properties, and is preferably less than 10 mass%, and more preferably less than 9 mass%.

[0023] The weight average molecular weight (Mw) of component (A) is preferably at least 10,000, more preferably at least 30,000, from the viewpoint of good shape retention and vibration resistance, and is preferably at most 80,000, more preferably at most 70,000. In addition, the ratio of Mw to number average molecular weight (Mn), Mw / Mn, is preferably at least 1.0 and not more than 2.0, from the viewpoint of good performance as a dispersant.

[0024] The (A) component can be produced under the conditions for copolymerization of general-purpose vinyl polymers. For example, water can be used as the solvent. The reaction temperature can be in the range of 50°C to 100°C. The reaction time depends on the reaction temperature, but can be in the range of 0.5 hours to 10 hours. The pH during production is preferably 3 or less.

[0025] The component (A) may be added as it is in the form of a copolymer, or may be added together with a suitable solvent (or dispersion medium). The solvent (or dispersion medium) is preferably water, and adding it together with water is preferred from the viewpoint of convenience. When adding it as a water solution (or dispersion), it is necessary to add the amount of water required for the composition of the present application, but this amount can be ignored when the concentration of the water solution (or dispersion) is high or the amount added is small.

[0026] Next, the component (B) will be described. The component (B) is represented by the general formula (b1) [ka] [In the formula, R 1brepresents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. b represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), ammonium, or an organic ammonium. A structural unit (B1) represented by the formula: General formula (b2) [ka] [In the formula, R 2b represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. nb represents the average number of moles added of 10 or more and less than 80. R 3b represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms. Copolymer B has a structural unit (B2) represented by the following formula:

[0027] The structural unit (B1) represented by general formula (b1) can be introduced into copolymer B by using a monomer represented by general formula (b1') as the raw material. [ka] [In the formula, R 1b represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. a represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), ammonium, or an organic ammonium.

[0028] M in general formula (b1') b Examples of the cation include a hydrogen atom, alkali metals such as lithium, sodium, and potassium, and alkaline earth metals such as magnesium and calcium. In view of good dispersibility, a hydrogen atom or an alkali metal is preferred.

[0029] R in general formula (b1') 1b Examples of the alkyl group include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, etc. In terms of good shape retention and vibration properties, a hydrogen atom and a methyl group are preferred, and a hydrogen atom is more preferred.

[0030] The structural unit (B2) represented by general formula (b2) can be introduced into copolymer B by using a monomer represented by general formula (b2') as the raw material. [ka] [In the formula, R 2b represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. nb represents the average number of moles added of 10 or more and less than 80. R 3b represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms.

[0031] R in general formula (b2') 2b Specific examples of the alkyl group include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, etc. In terms of obtaining the copolymer in good yield, a hydrogen atom and a methyl group are preferred, and a methyl group is more preferred.

[0032] The average number of moles added nb of general formula (b2') is preferably 10 or more, more preferably 15 or more, and even more preferably 20 or more in terms of good vibration property, and is preferably less than 80, more preferably less than 60, and even more preferably less than 40. In the present application, two or more types of monomers of general formula (b2) may be used. When two or more types of monomers are used, the average number of moles added nb is defined as the average number of moles added calculated according to the molar ratio thereof.

[0033] R in general formula (b2') 3b Specific examples of the alkyl group include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, a hexyl group, a 2-ethylhexyl group, a cyclohexyl group, an octyl group, a cyclooctyl group, a decyl group, a dodecyl group, a tetradecyl group, a hexadecyl group, an octadecyl group, etc. In terms of good dispersibility, a hydrogen atom and a methyl group are preferred, and a methyl group is more preferred.

[0034] The proportion of the structural unit (B1) relative to the total of the structural units (B1) and (B2) is preferably 5 mass % or more, more preferably 10 mass % or more, and even more preferably 15 mass % or more, in terms of good vibration properties, and is preferably less than 20 mass %, more preferably less than 18 mass %.

[0035] The weight average molecular weight (Mw) of component (B) is preferably at least 10,000, more preferably at least 30,000, from the viewpoint of good shape retention and vibration resistance, and is preferably at most 80,000, more preferably at most 70,000. In addition, the ratio of Mw to number average molecular weight (Mn), Mw / Mn, is preferably at least 1.0 and not more than 2.0, from the viewpoint of good performance as a dispersant.

[0036] The (B) component can be produced under the conditions for copolymerization of general-purpose vinyl polymers. For example, water can be used as the solvent. The reaction temperature can be in the range of 50°C to 100°C. The reaction time varies depending on the reaction temperature, but can be in the range of 0.5 hours to 10 hours. The pH during production is preferably 3 or less.

[0037] The component (B) may be added as it is in the form of a copolymer, or may be added together with a suitable solvent (or dispersion medium). The solvent (or dispersion medium) is preferably water, and adding it together with water is preferred from the viewpoint of convenience. When it is added as a water solution (or dispersion), it is necessary to add the amount of water required for the composition of the present application, but this amount can be ignored when the concentration of the water solution (or dispersion) is high or the amount added is small.

[0038] The mass ratio of component (A) to component (B), [component (A) / component (B)], is preferably 3 or less, more preferably 2.0 or less, even more preferably 1.5 or less, and is preferably 0.2 or more, more preferably 0.5 or more, even more preferably 0.67 or more.

[0039] From the viewpoint of good dispersibility, it is preferable that the proportion of the structural unit (A1) relative to the total of the structural units (A1), (A2), and (A3) is smaller than the proportion of the structural unit (B1) relative to the total of the structural units (B1) and (B2).

[0040] The hydraulic composition dispersant composition of the present invention may contain additives such as foaming agents, thickeners, foaming agents, preservatives, and antifoaming agents in addition to the components (A) and (B). These additives may be contained in an amount of 0.01% by mass or more and 2% by mass or less relative to the components (A) and (B). The antifoaming agents include one or more types of antifoaming agents selected from silicone-based antifoaming agents, fatty acid ester-based antifoaming agents, ether-based antifoaming agents, polyalkylene oxide-based antifoaming agents, alkyl phosphate ester-based antifoaming agents, and acetylene glycol-based antifoaming agents. The defoaming agent is preferably one or more defoaming agents selected from silicone-based defoaming agents, fatty acid ester-based defoaming agents, and ether-based defoaming agents.

[0041] The hydraulic powder used in the hydraulic composition of the present invention is a powder that hardens when mixed with water, and examples thereof include ordinary Portland cement, high-early-strength Portland cement, ultra-high-early-strength Portland cement, sulfate-resistant Portland cement, low-heat Portland cement, white Portland cement, and ecocement (e.g., JIS R5214, etc.). Among these, from the viewpoint of shortening the time required for the hydraulic composition to reach a required strength, a cement selected from early-early-strength Portland cement, ordinary Portland cement, sulfate-resistant Portland cement, and white Portland cement is preferred, and a cement selected from early-early-strength Portland cement and ordinary Portland cement is more preferred.

[0042] The hydraulic powder may contain blast furnace slag, fly ash, silica fume, anhydrous gypsum, etc., or may contain non-hydraulic limestone fine powder. As the hydraulic powder, blast furnace cement, fly ash cement, or silica fume cement, which is a mixture of cement and blast furnace slag, fly ash, silica fume, etc., may be used. It is preferable to contain blast furnace slag or fly ash from the viewpoint of using a low-quality hydraulic composition. Examples of blast furnace slag and fly ash include those described in JIS R5201.

[0043] When the hydraulic powder contains blast furnace slag and / or fly ash, the content of blast furnace slag and / or fly ash in the hydraulic powder is preferably 5 mass% or more, more preferably 10 mass% or more, even more preferably 15 mass% or more, and preferably 70 mass% or less, more preferably 60 mass% or less, even more preferably 55 mass% or less.

[0044] The water contained in the hydraulic composition is preferably water that is free of impurities and is appropriately purified, but well water and industrial water may also be used. Tap water, purified water, and ion-exchanged water are preferred.

[0045] In addition, the ratio of water to the hydraulic powder in the hydraulic composition is preferably 5 mass% or more, more preferably 10 mass% or more, and preferably 45 mass% or less, more preferably 40 mass% or less, and even more preferably 35 mass% or less, from the viewpoints of strength expression and moldability of the hydraulic composition.

[0046] The amount of component (A) added is preferably 0.01 mass % or more, more preferably 0.05 mass % or more, based on the hydraulic powder in the hydraulic composition, in terms of good dispersibility of the hydraulic composition, and is preferably 1.0 mass % or less, more preferably 0.5 mass % or less, and even more preferably 0.3 mass % or less.

[0047] The amount of component (B) added is preferably 0.01 mass % or more, more preferably 0.05 mass % or more, based on the hydraulic powder in the hydraulic composition, in terms of good dispersibility of the hydraulic composition, and is preferably 1.0 mass % or less, more preferably 0.5 mass % or less, and even more preferably 0.3 mass % or less.

[0048] The dispersant of the present invention has good dispersibility, and therefore can be effective even for low-quality aggregates containing blast furnace slag, fly ash, etc. In addition, a hydraulic composition containing the dispersant of the present invention and highly dispersible blast furnace slag, fly ash, etc. can be provided. EXAMPLES

[0049] <Examples and Comparative Examples> The present invention will be described in detail below with reference to examples and comparative examples, but the present invention is not limited to the following descriptions.

[0050] The materials used in the examples and comparative examples are shown below. <Component (A)> Copolymer A was produced using the following compounds as raw materials for the structural units (A1) and (A2). Raw material for structural unit (A1): acrylic acid Raw material for structural unit (A2): 3-methyl-3-butenyl ether of polyethylene glycol (hereinafter referred to as TPEG) represented by the following formula (1), [ka] (In the formula, na represents 60 (TPEG60) or 66 (TPEG66)). Or, 2-methyl-2-propenyl ether of polyethylene glycol (hereinafter referred to as HPEG) represented by the following formula (2): [ka]

[0051] <Production of component (A) by copolymerization reaction> Taking the component (A) of Comparative Example 2 as an example, a method for producing the component (A) will be described below. 220.7 parts of TPEG66 and 141.3 parts of water were charged into a glass reaction vessel equipped with a stirrer, and the mixture was replaced with nitrogen while stirring, and the temperature was raised to 80°C in a nitrogen atmosphere. Then, 0.7 parts of hydrogen peroxide (35%) was added. An aqueous solution of 21.3 parts of acrylic acid dissolved in 31.9 parts and an aqueous solution of 1.2 parts of 3-mercaptopropionic acid dissolved in 38.0 parts of water were dropped into the vessel over 3.0 hours, respectively, and an aqueous solution of 0.3 parts of L-ascorbic acid dissolved in 32.2 parts of water was dropped into the vessel over 3.5 hours. Then, the mixture was aged at the same temperature (80°C) for 1 hour. After the aging, the mixture was neutralized with 12.3 parts of 48% aqueous sodium hydroxide solution to obtain an aqueous solution containing a copolymer (A) having a weight average molecular weight of 56,000.

[0052] <(B) component> Copolymer B was produced using the following compounds as raw materials for the structural units (B1) and (B2). Raw material for structural unit (B1): methacrylic acid Raw material for structural unit (B2): methyl polyethylene glycol methacrylate ester (hereinafter referred to as MEPEG) represented by the following formula (3) [ka] [In the formula, nb represents 23 (referred to as MEPEG23), 60 (referred to as MEPEG60), or 120 (referred to as MEPEG120).] MEPEG60 was obtained by mixing MEPEG120 (nb is 120) and MEPEG23 (nb is 23) in a molar ratio of 3.6 / 5.9. The nb of the resulting mixture was calculated from the nb value and molar fraction of each component using the following formula. 120×(3.6 / 9.5)+23×(5.9 / 9.5)=60

[0053] <Production of component (B) by copolymerization reaction> Taking the component (B) of Comparative Example 1 as an example, a method for producing the component (B) will be described below. 356 parts of ion-exchanged water was charged into a glass reaction vessel (four-neck flask) equipped with a stirrer, and the inside of the reaction vessel was replaced with nitrogen while stirring, and heated to 80°C under a nitrogen atmosphere. Next, a monomer aqueous solution obtained by mixing 318 parts of the above-mentioned MEPEG23, 67 parts of methacrylic acid, and 176 parts of ion-exchanged water, a mixed aqueous solution of 2.8 parts of 3-mercaptopropionic acid and 27.7 parts of ion-exchanged water, and a mixed aqueous solution of 3.3 parts of ammonium persulfate and 18.6 parts of ion-exchanged water were dropped over 2 hours, and after the dropwise addition, a mixed aqueous solution of 1.1 parts of ammonium persulfate and 6.2 parts of ion-exchanged water was further dropped over 0.5 hours. After the dropwise addition, the temperature was maintained at 80°C for 1 hour, and aging was performed. Thereafter, the reaction solution was neutralized using an aqueous sodium hydroxide solution at a temperature of 80°C or less to obtain an aqueous solution containing a copolymer (B) having a weight average molecular weight of 60,000.

[0054] Table 1 shows the hydraulic composition dispersant compositions produced in the Examples and Comparative Examples, and the mass ratio of the (A) component to the (B) component cement. [Table 1] <Other materials> Cement: A 1:1 mixture of ordinary Portland cement manufactured by Taiheiyo Cement Co., Ltd. and ordinary Portland cement manufactured by Sumitomo Osaka Cement Co., Ltd. (density 3.16 g / cm 3 ) Fly ash: Fly ash type II (Techno Chubu Co., Ltd.) (density 2.32 g / cm 3 ) Blast furnace slag: Blast furnace slag powder 4000 Blaine, made by Nippon Steel blast furnace cement, density 2.91g / cm 3 ) Fine aggregate: mountain sand, density 2.72g / cm 3

[0055] <Production of hydraulic composition> The hydraulic powder and fine aggregate were added to a mortar mixer specified in JIS R 5201 in the proportions shown in Table 2, and dry mixing (60 rpm, 10 seconds) was performed. Thereafter, water containing component (A) or component (B) was added in the amounts shown in Table 1, and the mixture was kneaded (60 rpm, 120 seconds) to prepare the hydraulic compositions shown in Table 3. [Table 2]

[0056] Using the hydraulic composition dispersant compositions of each of the Examples and Comparative Examples in Table 3, the shape retention and vibration elongation were evaluated. [Table 3]

[0057] <Evaluation of shape retention> The hydraulic composition immediately after mixing was filled into two flow cones (upper diameter 70 mm × lower diameter 100 mm × height 60 mm) specified in JIS R5201. The flow of one of the flow cones was immediately measured on a 30 cm × 30 cm plastic plate, which was taken as the flow immediately after filling. The flow of the other flow cone was measured on a 30 cm × 30 cm plastic plate after leaving it for 3 minutes after filling, which was taken as the flow immediately after filling. The difference between the flow immediately after filling and the flow after leaving it for 3 minutes after filling was taken as shape retention.

[0058] <Evaluation of vibration extension rate 1 and vibration extension rate 2> The hydraulic composition immediately after kneading was filled into a flow cone (upper diameter 70 mm × lower diameter 100 mm × height 60 mm) described in JIS R5201. After leaving it for 3 minutes after filling, the flow was measured on a 30 cm × 30 cm plastic plate, and the result was recorded as (b) no tap in Table 2. After tapping three times on a flow tester (product name C54, JIS R 5201 compliant product, manufactured by Maruto Seisakusho), the flow was measured, and the result was recorded as (c) three taps in Table 3. After tapping three more times, the flow was measured, and the result was recorded as (d) six taps in Table 3. Vibration extension rate 1 was calculated according to the formula [(c)-(b)] / (b)(%), and vibration extension rate 2 was calculated according to the formula [(d)-(b)] / (b).

[0059] From Table 3, Comparative Example 1, which does not contain component (A), had a shape retention of 64 mm, but a small vibration extension rate. Comparative Examples 3, 5, 7, 8, and 11, which also do not contain component (A), had small shape retention and vibration extension rates. Comparative Examples 2, 9, and 12, which do not contain component (B), had good shape retention, but a low vibration extension rate. Comparative Example 6, which also does not contain component (B), had both low shape retention and vibration extension rate. Comparative Examples 4 and 10, in which component (B) had a large nb of 120, also had low shape retention and vibration extension rate.

[0060] In this way, by optimizing the composition ratio of components (A) and (B) and na and nb, a dispersant composition having good shape retention and vibration elongation rate could be obtained.

Claims

1. A dispersant composition for hydraulic compositions, comprising the following components (A) and (B): Component (A): General formula (a1) 【Chemical 1】 [In the formula, R １ａ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ａ represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), ammonium, or an organic ammonium. A structural unit (A1) represented by the formula: General formula (a2) 【Chemistry 2】 [In the formula, R ２ａ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. X represents an alkylene group having 1 to 4 carbon atoms. na represents the average number of moles added of 20 or more but less than 150. R ３ａ represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or a hydrocarbon group having 1 to 4 carbon atoms which may contain a heteroatom. A structural unit (A2) represented by the formula: and optionally a compound of general formula (a3) 【Chemistry 3】 [In the formula, R ４ａ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ５ａ represents an alkyl group having 1 to 18 carbon atoms or a hydrocarbon group having 1 to 4 carbon atoms which may contain a heteroatom. A copolymer having a structural unit (A3) represented by the following formula: Copolymer A, in which the proportion of the structural unit (A1) relative to the total of the structural units (A1), (A2), and (A3) is 3% by mass or more and less than 10% by mass. (B) Component: General formula (b1) 【Chemistry 4】 [In the formula, R １ｂ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ｂ represents a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), ammonium, or an organic ammonium. A structural unit (B1) represented by the formula: General formula (b2) 【Chemistry 5】 [In the formula, R ２ｂ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. nb represents the average number of moles added of 10 or more but less than 80. R ３ｂ represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms. A copolymer having a structural unit (B2) represented by the following formula: Copolymer B, in which the proportion of the structural unit (B1) relative to the total of the structural units (B1) and (B2) is 5% by mass or more and less than 20% by mass.

2. 2. The dispersant composition for hydraulic compositions according to claim 1, wherein the hydraulic composition comprises a hydraulic powder containing cement and blast furnace slag and / or fly ash, and the content of the blast furnace slag and / or fly ash in the hydraulic powder is 5% by mass or more and 60% by mass or less.

3. 2. The dispersant composition for hydraulic compositions according to claim 1, wherein the proportion of the structural unit (A1) relative to the total of the structural units (A1), (A2), and (A3) is 5% by mass or more and less than 9% by mass.

4. R of the structural unit (B1) １ｂ The dispersant composition for hydraulic compositions according to claim 1, wherein is an alkyl group having 1 to 4 carbon atoms.

5. The dispersant composition for hydraulic compositions according to claim 1 , which does not contain the structural unit (A3).

6. 2. The dispersant composition for hydraulic compositions according to claim 1, wherein the weight average molecular weight of component (A) is 10,000 or more and 80,000 or less.

7. 2. The dispersant composition for hydraulic compositions according to claim 1, wherein the weight average molecular weight of component (B) is 10,000 or more and 80,000 or less.

8. 2. The dispersant composition for hydraulic compositions according to claim 1, wherein the proportion of the structural unit (A1) to the total of the structural units (A1), (A2), and (A3) is lower than the proportion of the structural unit (B1) to the total of the structural units (B1) and (B2).

9. A hydraulic composition comprising: a hydraulic powder containing cement and blast furnace slag and / or fly ash; water; and the dispersant composition for hydraulic compositions according to any one of claims 1 to 8.

10. The hydraulic composition according to claim 9, wherein the ratio of water to hydraulic powder is 5% by mass or more and 45% by mass or less.

Images