Dispersants and hydrohardening agents for hydraulic components

Abstract

The present invention provides a dispersant for hydraulic compositions that exhibits high dispersibility and can reduce the viscosity of hydraulic compositions. [Solution] A dispersant for hydraulic compositions comprising a polymer (P) having a constituent unit (1) formed from a compound represented by general formula (1), and a constituent unit (2) formed from a compound containing at least one selected from acrylic acid, methacrylic acid, fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, and salts thereof, and an ether compound (A) which is a compound obtained by adding 1 to 500 moles of alkylene oxide having 2 to 4 carbon atoms to 1 mole of a 1 to 4 valent aliphatic alcohol having 2 to 24 carbon atoms, wherein the mass average molecular weight of the polymer (P) is 5,000 to 5,000,000, and the mass ratio value (A / P) of the ether compound (A) to the polymer (P) is greater than 0 and 0.25 or less.

Description

Technical Field

[0001] The present invention relates to a dispersant for a hydraulic composition and a hydraulic composition. More specifically, it relates to a dispersant for a hydraulic composition that has high dispersibility and can reduce the viscosity of the hydraulic composition, and a hydraulic composition.

Background Art

[0002] Conventionally, a dispersant for a hydraulic composition has a function of imparting fluidity to a hydraulic composition such as concrete (see, for example, Patent Document 1).

[0003] As such a dispersant for a hydraulic composition, for example, naphthalene-based compounds, polycarboxylic acid-based compounds, etc. are known.

[0004] Furthermore, in recent years, with the depletion of high-quality aggregates such as river sand, the proportion of use of types of aggregates (aggregates of inferior quality) that were not actively used conventionally has been increasing. A hydraulic composition using such aggregates (aggregates of inferior quality compared to river sand, etc.) is known to have high viscosity even at a normal water-binder ratio (W / B), resulting in poor workability.

[0005] Under such circumstances, those that reduce the viscosity of the hydraulic composition (water-reducing agents, admixtures) such as Patent Documents 2 and 3 have been reported.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0007] However, the water-reducing agent described in Patent Document 2 and the admixture described in Patent Document 3 were not yet sufficiently effective in reducing the viscosity of the hydraulic composition, and there was room for further improvement.

[0008] In other words, there was a need for the development of a dispersant (a dispersant for hydraulic compositions) that could further reduce the viscosity of hydraulic compositions (even if aggregates of lower quality than river sand, etc., were used).

[0009] In view of the above circumstances, the present invention aims to provide a dispersant for hydraulic compositions that has high dispersibility and can reduce the viscosity of hydraulic compositions. [Means for solving the problem]

[0010] The inventors of the present invention have diligently researched and found that the above problems can be solved by using a predetermined polymer and a predetermined ether compound, and by setting their ratio (predetermined ether compound / predetermined polymer) within a predetermined range. According to the present invention, the following dispersant for hydraulic compositions and hydraulic compositions are provided.

[0011] [1] A polymer (P) having a constituent unit (1) formed from a compound represented by the following general formula (1), and a constituent unit (2) formed from a compound containing at least one selected from acrylic acid, methacrylic acid, fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, and salts thereof, Ether compounds (A) are compounds obtained by adding 1 to 500 moles of an alkylene oxide with 2 to 4 carbon atoms to 1 to 4 valent aliphatic alcohol with 2 to 24 carbon atoms, It contains, The mass-average molecular weight of the polymer (P) is 5,000 to 5,000,000. A dispersant for hydraulic compositions, characterized in that the mass ratio (A / P) of the ether compound (A) to the polymer (P) is greater than 0 and 0.25 or less.

[0012] [Chemical formula] (In general formula (1), X is an alkenyl group having 6 to 24 carbon atoms, AO is an alkyleneoxy group having 2 to 4 carbon atoms, n is an integer of 1 to 500, and Y is a hydrogen atom or a hydrocarbon group having 1 to 24 carbon atoms.)

[0013] [2] The dispersant for a hydraulic composition according to [1], wherein the value of the mass ratio of the structural unit (1) to the structural unit (2) in terms of sodium salt (the structural unit (1) / the structural unit (2) in terms of sodium salt) is 99 / 1 to 50 / 50.

[0014] [3] The dispersant for a hydraulic composition according to [1], wherein in the general formula (1), X is an alkenyl group having 8 to 18 carbon atoms.

[0015] [4] The ether compound (A) is a compound obtained by adding 1 to 500 moles of an alkylene oxide having 2 to 4 carbon atoms to 1 mole of a monovalent aliphatic alcohol having 8 to 18 carbon atoms and having an unsaturated bond, The dispersant for a hydraulic composition according to [1], wherein the mass ratio of ethylene oxide in the alkylene oxide is 60% by mass or more.

[0016] [5] The dispersant for a hydraulic composition according to [1], wherein the value of the mass ratio of the ether compound (A) to the polymer (P) (A / P) is 0.01 to 0.20.

[0017] [6] A hydraulic composition comprising a hydraulic binder, water, and the dispersant for a hydraulic composition according to any one of [1] to [5]. [Advantages of the Invention]

[0018] The dispersant for a hydraulic composition of the present invention has an effect of having high dispersibility and reducing the viscosity of the hydraulic composition.

[0019] The hydraulic composition of the present invention exhibits the effect of reducing viscosity by containing the dispersant for the hydraulic composition of the present invention.

Embodiments for Carrying out the Invention

[0020] Hereinafter, embodiments of the present invention will be described. However, the present invention is not limited to the following embodiments. Therefore, it should be understood that appropriate changes, improvements, etc. can be made to the following embodiments based on the ordinary knowledge of those skilled in the art without departing from the gist of the present invention. In the following examples, etc., unless otherwise specified, % means mass %, and parts means parts by mass.

[0021] (1) Dispersant for hydraulic composition: The dispersant for the hydraulic composition of the present invention contains a structural unit (1) formed from a compound represented by the following general formula (1), and a structural unit (2) formed from a compound containing at least one selected from acrylic acid, methacrylic acid, fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, and salts thereof. It contains a polymer (P) and an ether compound (A) which is a compound obtained by adding 1 to 500 moles of an alkylene oxide having 2 to 4 carbon atoms to 1 mole of a monovalent to tetravalent aliphatic alcohol having 2 to 24 carbon atoms. The mass average molecular weight of the polymer (P) is 5000 to 5000000, and the value (A / P) of the mass ratio of the ether compound (A) to the polymer (P) is more than 0 and 0.25 or less.

[0022]

Chemical formula

[0023] This dispersant for hydraulic compositions has high dispersibility and can reduce the viscosity of hydraulic compositions. Furthermore, it can shorten the time required to mix the hydraulic compositions during preparation.

[0024] (1-1) Polymer (P): Polymer (P) contains constituent units (1) and (2), and has a predetermined mass-average molecular weight. The constituent units (1), (2), and mass-average molecular weight of polymer (P) are described below.

[0025] (1-1a) Constituent unit (1): The constituent unit (1) is a constituent unit formed from the compound represented by general formula (1), and in particular, X in general formula (1) is an alkenyl group having 6 to 24 carbon atoms. Thus, polymer (P) is one in which the alkenyl group X in general formula (1) has a large number of carbon atoms.

[0026] As described above, X in general formula (1) is an alkenyl group having 6 to 24 carbon atoms, preferably an alkenyl group having 8 to 18 carbon atoms, and more preferably 8 to 9 carbon atoms.

[0027] An alkenyl group is a linear, branched, or cyclic monovalent aliphatic unsaturated hydrocarbon group having at least one non-aromatic carbon-carbon double bond. Among these, linear groups are preferred.

[0028] Examples of alkenyl groups having 6 to 24 carbon atoms include hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tridecenyl, tetradecenyl, pentadecenyl, hexadecenyl, heptadecenyl, octadecenyl, nonadecenyl, icocenyl, heneicocenyl, dococenyl, tricocenyl, and tetracocenyl groups.

[0029] In general formula (1), AO is an alkylene oxy group having 2 to 4 carbon atoms (however, if multiple alkylene oxy groups are present, one type or two or more types may be used). Of these, an alkylene oxy group having 2 carbon atoms is preferred.

[0030] In general formula (1), n ​​is the average number of moles of AO added. n can be a number from 1 to 500, preferably from 2 to 300, and more preferably from 5 to 150.

[0031] In general formula (1), Y is a hydrogen atom or a hydrocarbon group having 1 to 24 carbon atoms, and of these, it is preferably a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms, and more preferably a hydrogen atom or a hydrocarbon group having 1 carbon atom.

[0032] (1-1b) Constituent unit (2): The constituent unit (2) is a constituent unit formed from a compound containing at least one selected from acrylic acid, methacrylic acid, fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, and salts thereof. Constituent units formed from these specific compounds have high dispersibility and can reduce the viscosity of the hydraulic composition.

[0033] In general formula (2), it is preferable that at least acrylic acid or a salt thereof is included among acrylic acid, methacrylic acid, fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, and salts thereof. With these compounds, dispersibility is further enhanced and the viscosity of the hydraulic composition can be further reduced.

[0034] (Constituent units (1) / Constituent units converted to sodium salt (2)) The polymer (P) preferably has a mass ratio of constituent unit (1) to constituent unit (2) converted to sodium salt (constituent unit (1) / constituent unit (2) converted to sodium salt) of 99 / 1 to 50 / 50, and more preferably 95 / 5 to 68 / 42. By using such a ratio, dispersibility can be further increased and the viscosity of the hydraulic composition can be further reduced.

[0035] Furthermore, the sodium salt conversion in "Constituent Unit (2) converted to sodium salt equivalent" can be carried out as follows: That is, all unsaturated carboxylic acids and their salts in constituent unit (2) are converted as if they were all sodium salts of unsaturated carboxylic acids. For example, all constituent units formed from acrylic acid are converted as constituent units formed from sodium acrylate, and all constituent units formed from maleic acid and maleic anhydride are converted as constituent units formed from disodium maleate.

[0036] (1-1c) Other structural units: Polymer (P) may have other constituent units in addition to the above-mentioned constituent units (1) and (2). Examples of such other constituent units include those formed from compounds such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, alkyl (meth)acrylate, (meth)allyl sulfonic acid (salt), (meth)acrylamide, and styrene.

[0037] The polymer (P) has a mass-average molecular weight of 5,000 to 5,000,000, preferably 5,000 to 1,000,000, and more preferably 8,000 to 5,000,000. By having such a mass-average molecular weight, high dispersibility can be achieved and the viscosity of the hydraulic composition can be reduced.

[0038] The mass-average molecular weight of this polymer (P) is measured by gel permeation chromatography.

[0039] The content of polymer (P) in the dispersant for hydraulic compositions is not particularly limited, but can be, for example, 10 to 100% by mass.

[0040] (1-2) Ether compounds (A): The ether compound (A) is a compound obtained by adding 1 to 500 moles of an alkylene oxide with 2 to 4 carbon atoms to 1 mole of a 1 to 4 valent aliphatic alcohol with 2 to 24 carbon atoms. Furthermore, the mass ratio (A / P) of this ether compound (A) to polymer (P) is greater than 0 and less than or equal to 0.25. By satisfying these conditions, high dispersibility can be achieved and the viscosity of the hydraulic composition can be reduced.

[0041] Furthermore, the ether compound (A) preferably contains a compound obtained by adding 1 to 500 moles of a C2-C4 alkylene oxide to 1 mole of a monovalent aliphatic alcohol having 8 to 18 carbon atoms and unsaturated bonds. In this case, the mass ratio of ethylene oxide (C2 alkylene oxide) in the alkylene oxide is preferably 60% by mass or more, and more preferably 80% by mass or more. By satisfying these conditions, the dispersibility can be further improved and the viscosity of the hydraulic composition can be further reduced.

[0042] Furthermore, the mass ratio (A / P) of the ether compound (A) to the polymer (P) is preferably 0.01 to 0.20, and more preferably 0.01 to 0.18. By setting the value within this range, dispersibility can be further improved and the viscosity of the hydraulic composition can be further reduced.

[0043] The ether compound (A) can be an unreacted product during the synthesis reaction of polymer (P), but the ether compound (A) may also be added separately.

[0044] Here, when using unreacted material (unreacted ether compound) from the synthesis reaction of polymer (P) as ether compound (A) (specifically, as part of ether compound (A)), in order to satisfy the above A / P ratio, the synthesis must be carried out so that the amount of unreacted material (unreacted ether compound) from the synthesis reaction of polymer (P) does not exceed the upper limit of A / P. To achieve this, a compound that forms constituent unit (1) and a compound that forms constituent unit (2) with sufficient purity are used, and polymer (P) is obtained by polymerization using an appropriate method.

[0045] The polymer (P) can be synthesized by conventionally known methods. Conventionally known methods include radical polymerization using water as the solvent, radical polymerization using organic solvents, and solvent-free radical polymerization.

[0046] The radical polymerization initiator used in radical polymerization is not particularly limited in type, as long as it decomposes at the polymerization reaction temperature and generates radicals, such as peroxides like benzoyl peroxide, hydrogen peroxide, ammonium persulfate, sodium persulfate, and potassium persulfate, and azo compounds like 2,2'-azobisisobutyronitrile and 2,2'-azobis(2-methylbutyronitrile).

[0047] In addition, reducing agents such as sodium bisulfite, sodium bisulfite, Fe(II) salts such as Mohr's salt, sodium hydroxymethanesulfinate dihydrate, and ascorbic acid, as well as amine compounds such as ethylenediamine and glycine, can also be used as accelerators.

[0048] Furthermore, a chain transfer agent can be used to set the mass-average molecular weight of the resulting polymer (P) within a desired range.

[0049] In polymerization reactions, polymerization conditions such as polymerization temperature are appropriately determined by the polymerization method, solvent, polymerization initiator, and chain transfer agent used. However, the polymerization temperature is preferably 0°C or higher at the lower limit and 150°C or lower at the upper limit. More preferably 30°C or higher at the lower limit, and even more preferably 50°C or higher. Furthermore, the upper limit is more preferably 120°C or lower, and even more preferably 100°C or lower.

[0050] (1-3) Other dispersant components: The dispersant for hydraulic compositions of the present invention may contain other dispersant components in addition to the polymer (P) and the ether compound (A).

[0051] Other dispersant components include, for example, setting retarders consisting of sugars, oxycarboxylates, etc., dispersing components consisting of sodium ligninsulfonate, etc., air-enhancing agents consisting of anionic surfactants, etc., defoaming agents consisting of oxyalkylene compounds, etc., curing accelerators consisting of alkanolamines, etc., shrinkage reducing agents consisting of polyoxyalkylene alkyl ethers, etc., thickeners consisting of cellulose ether compounds, etc., preservatives consisting of isothiazolinone compounds, etc., rust inhibitors consisting of nitrites, etc.

[0052] Furthermore, the other dispersant components may be used individually or in combination of two or more.

[0053] (1-4) Method for producing dispersants for hydraulic compositions: The dispersant for hydraulic compositions of the present invention can be manufactured as follows. First, a polymer (P) is synthesized using a compound that forms a constituent unit (1) and a compound that forms a constituent unit (2) as raw materials. At this time, an ether compound (A) (i.e., the compound that forms a constituent unit (1)) is used as a raw material for polymer (P), but the unreacted ether compound (A) can be used as is after the polymer (P) synthesis reaction. Then, ether compound (A) is added as needed to satisfy the desired A / P (the mass ratio of ether compound (A) to polymer (P)). The ether compound (A) added at this time may be the same type as the ether compound (A) used as a raw material for polymer (P), or it may be a different type. Then, other dispersant components are added as needed.

[0054] (2) Hydraulic composition: The hydraulic composition of the present invention contains a hydraulic binder, water, and a dispersant for the hydraulic composition of the present invention.

[0055] Such hydraulic compositions have reduced viscosity due to the inclusion of the hydraulic composition dispersant of the present invention.

[0056] (2-1) Hydraulic binder: Examples of hydraulic binders include various types of Portland cement such as ordinary Portland cement, moderate-heat Portland cement, low-heat Portland cement, rapid-hardening Portland cement, and sulfate-resistant Portland cement, as well as various types of cement such as blast furnace cement, fly ash cement, and silica fume cement. Furthermore, examples include various types of gypsum such as anhydrous gypsum, hemihydrate gypsum, and dihydrate gypsum, and powders with latent hydraulic properties, such as a combination of blast furnace slag fine powder and calcium hydroxide, combined with an alkaline stimulant.

[0057] Furthermore, the hydraulic binder may be appropriately selected and used in combination with various admixtures such as fly ash, blast furnace slag powder, limestone powder, stone powder, silica fume, and expansive agents.

[0058] (2-2) Dispersant for hydraulic compositions: In the hydraulic composition of the present invention, there are no particular restrictions on the content ratio of the dispersant for the hydraulic composition of the present invention, and it can be set as appropriate. For example, the content ratio of the dispersant for the hydraulic composition of the present invention can be 0.001 to 3.0 parts by mass in terms of solid content per 100 parts by mass of hydraulic binder.

[0059] (2-3) Aggregates: The hydraulic composition of the present invention may contain fine aggregate, coarse aggregate, etc., similar to conventionally known hydraulic compositions.

[0060] Examples of fine aggregates include river sand, mountain sand, land sand, sea sand, silica sand, crushed sand, and various slag aggregates, but they may also contain fine particles such as clay.

[0061] Examples of coarse aggregates include river gravel, mountain gravel, land gravel, crushed stone, various types of slag coarse aggregates, and lightweight aggregates.

[0062] (2-4) Other compositional components: The hydraulic composition of the present invention may further contain other compositional components as appropriate, within a range that does not impair its effectiveness. Examples of such other compositional components include: a setting retarder consisting of sugars or oxycarboxylates; various water-reducing agents; an AE agent consisting of anionic surfactants; an antifoaming agent consisting of oxyalkylene compounds; a curing accelerator consisting of alkanolamines; a shrinkage reducing agent consisting of polyoxyalkylene alkyl ethers; a thickener consisting of cellulose ether compounds; a preservative consisting of isothiazolinone compounds; and a rust inhibitor consisting of nitrites.

[0063] As for the content ratio of other compositional components, for example, it can be 0 to 5 parts by mass in terms of solid content per 100 parts by mass of hydraulic binder.

[0064] The hydraulic composition of the present invention can appropriately adopt conventionally known ratios for the ratio of water to hydraulic binder (water / binder ratio), for example, it can be 20 to 70% by mass.

[0065] (3) Cured product of hydraulic composition: The hydraulic composition of the present invention can be hardened to form a hardened product. Specifically, this hardened product may be hardened mortar (hardened mortar), hardened concrete (hardened concrete), etc.

[0066] A hardened body of a hydraulic composition can be produced by conventionally known methods. Specifically, this can be done by filling a mold or the like with the hydraulic composition and curing it at room temperature or by heating it with steam. [Examples]

[0067] The present invention will be described in detail below based on examples, but the present invention is not limited to these examples.

[0068] (Examples 1-17, Comparative Examples 1-3) (1) Dispersant for hydraulic compositions: First, the compounds (P1-1 to P1-11, P2-1 to P2-4) that form constituent units 1 and 2 of the polymer (P) used as a dispersant for hydraulic compositions in Examples 1 to 17 and Comparative Examples 1 to 3 are shown in Tables 1 and 2 below. Additionally, the ether compounds (A) (A1-1 to A1-11, A-12 to A-15) are shown in Table 3 below. In Table 3, EO represents ethylene oxide and PO represents propylene oxide.

[0069] [Table 1]

[0070] [Table 2]

[0071] [Table 3]

[0072] Next, the methods for producing each polymer (P) in Examples 1 to 17 and Comparative Examples 1 to 3 will be described below.

[0073] (Manufacturing Example 1) Specifically, the method for producing polymer (P) in Example 1 involved first adding 50 moles of EO (ethylene oxide) to 95.02 g of tap water and 1 mole of 7-octen-1-ol, and then adding 210.17 g of the compound to this compound. This compound was then charged into a reactor equipped with a thermometer, stirrer, dropping funnel, and nitrogen inlet tube, and uniformly dissolved while stirring. Subsequently, the atmosphere was purged with nitrogen, and the temperature of the reaction system was maintained at 65°C using a mantle heater.

[0074] Next, 2.30 g of 30% hydrogen peroxide solution was added to the reactor. Simultaneously, an aqueous solution prepared by uniformly dissolving 18.64 g of acrylic acid and 0.69 g of methacrylic acid in 38.66 g of tap water was added dropwise over 3 hours. At the same time, an aqueous solution prepared by dissolving 0.90 g of L-ascorbic acid and 1.15 g of 3-mercaptopropionic acid in 18.38 g of tap water was added dropwise over 3.5 hours. After that, the temperature of the reaction system was maintained at 65°C for 1 hour to complete the polymerization reaction.

[0075] Subsequently, a 30% sodium hydroxide aqueous solution was added to the reaction system to a pH of 8, and the concentration was adjusted with tap water to obtain a 40% aqueous solution of the reaction mixture (polymer (P)).

[0076] (Other manufacturing examples) Polymers (P) were produced in the same manner as in Production Example 1, except that the raw materials and reagents were changed to achieve the types and content percentages (mass%) of constituent units 1 and 2 shown in Table 4, thereby obtaining polymers (P) for Examples 2-17 and Comparative Examples 1-3.

[0077] The reaction mixtures obtained in each manufacturing example were analyzed by gel permeation chromatography (GPC) under the following measurement conditions. The resulting mass-average molecular weights are shown in Table 4.

[0078] <Measurement conditions> Equipment: Shodex GPC-101 (manufactured by Showa Denko Corporation) Columns: OHpak SB-G + SB-804 HQ + SB-802.5 HQ (manufactured by Showa Denko Corporation) Detector: Differential refractometer (RI) Eluent: 50 mM sodium nitrate aqueous solution Flow rate: 0.7mL / min Column temperature: 40℃ Sample concentration: Eluent solution with a sample concentration of 0.5% by weight. Standard substances: polyethylene oxide, polyethylene glycol

[0079] (Dispersant for hydraulic composition) Next, a dispersant for hydraulic compositions was prepared as follows. Specifically, first, the amount of unreacted ether compounds contained in each reaction mixture (containing polymer (P)) obtained by the polymer (P) production method was quantified by high-performance liquid chromatography (HPLC) to confirm the amount of unreacted ether compounds in the reaction mixture. Then, the ether compounds were added to the above reaction mixture and mixed while ensuring that the ratio of polymer (P) to ether compound (A) (A / P) satisfies the value shown in Table 4, and a dispersant for hydraulic compositions with an active ingredient content of 20% was prepared by dilution with tap water.

[0080] The measurement conditions for HPLC of the reaction mixture are shown below. <Measurement conditions> Equipment: Prominence (manufactured by Shimadzu Corporation) Column: Synergi 4μm Hydro-RP 80A (manufactured by Phenomenex) Detector: Differential refractometer (RI) Eluent: Acetonitrile / 0.1% phosphate exchange aqueous solution = 70 / 30 (volume %) Flow rate: 1.0mL / min Column temperature: 55℃ Sample concentration: Eluent solution with a sample concentration of 1.0% by mass.

[0081] [Table 4]

[0082] In Table 4, "(A) / (P)" indicates the mass ratio (A / P) of the ether compound (A) to the polymer (P).

[0083] (2) Hydraulic composition: Next, hydraulic compositions (mortar and concrete) were prepared using the dispersants prepared for each hydraulic composition.

[0084] (2-1) Mortar (mortar composition): In a temperature-controlled chamber maintained at 20°C ± 1°C, fine aggregate (land sand from the Oi River system, excluding particles that remained on a 2.5 mm sieve) and blast furnace slag cement type B (manufactured by Taiheiyo Cement) were added to a mortar mixer conforming to JIS R5201. The mixer was then operated at low speed for 10 seconds to agitate the mixture. Subsequently, a predetermined amount of additive (dispersant for hydraulic compositions) (Table 7 shows the addition rate of the dispersant for hydraulic compositions), 0.1 g of defoaming agent (AFK-2, manufactured by Takemoto Oil & Fat Co., Ltd.), and water (Gamagori City water supply) were added simultaneously. The mixer was then operated at low speed to agitate each component, and the mixture was kneaded for 210 seconds to obtain a mortar composition. The temperature of the obtained mortar compositions was checked, and all were found to be 20°C ± 1°C. Note that the additive and defoaming agent were used as part of the water. Table 5 below shows the amount of each component used.

[0085] [Table 5]

[0086] In Table 5, "W" indicates Gamagori City tap water, and "C" indicates blast furnace slag cement type B (equal parts mixture of Taiheiyo Cement, UBE Mitsubishi Cement, and Sumitomo Osaka Cement, density = 3.04 g / cm³). 3 ) indicates that "S" represents the terrestrial sand of the Oigawa River system (density = 2.60 g / cm³). 3 ) indicates.

[0087] (2-2) Concrete (concrete composition): Using a 55L nominal capacity twin-shaft mixer, each component shown in Table 6 (the addition rate of the hydraulic composition dispersant is shown in Table 7) was added to the mixer, and the mixture was kneaded for 90 seconds to prepare 30L of concrete composition.

[0088] The air content in the prepared concrete composition was adjusted by using 0.001% by mass of an antifoaming agent (product name AFK-2, manufactured by Takemoto Oil Co., Ltd.) relative to the total mass (B) of cement and fly ash. As shown in Table 6, the target slump flow was 65 ± 5 cm, and the target air content was 2.0% or less. In addition, each dispersant and antifoaming agent was used as part of the water.

[0089] [Air content (volume %)] The air content was measured in accordance with JIS A 1128 for the concrete composition immediately after mixing.

[0090] [Table 6]

[0091] In Table 6, "W" indicates Gamagori City tap water, and "C" indicates blast furnace slag cement type B (equal parts mixture of Taiheiyo Cement, UBE Mitsubishi Cement, and Sumitomo Osaka Cement, density = 3.04 g / cm³). 3 ) indicates that "FA" is equivalent to JIS Type II fly ash (manufactured by Chubu Fly Ash Co., Ltd., density = 2.39 g / cm³). 3 ) indicates that "S" represents the terrestrial sand of the Oigawa River system (density = 2.60 g / cm³). 3 ) indicates that "G" is crushed stone from Okazaki (density = 2.66 g / cm³). 3 This indicates the composition of the aggregate. "B" is a mixture of blast furnace slag cement (C) and fly ash (FA). "s / a" indicates the fine aggregate ratio.

[0092] [Table 7]

[0093] (evaluation) Various evaluations (viscosity, mixing speed, etc.) were performed on mortar (mortar composition) and concrete (concrete composition).

[0094] (1) Mortar composition: First, for mortar (mortar composition), the mortar flow value (mm) was measured and evaluated. [Mortar flow (mm)] Except for not performing tapping, the mortar flow (mm) immediately after mixing was measured in accordance with JIS R 5201.

[0095] (viscosity) [J14 funnel flow time (seconds)] The test was conducted in accordance with the "Fluidity Test Method for Filling Mortar" in the Japan Society of Civil Engineers' Standard Specifications for Concrete JSCE-F541.

[0096] The J14 funnel flow time (seconds) (viscosity) was evaluated according to the following evaluation criteria (levels). If S: is less than 21.0 seconds A: If the time is 21.0 seconds or more and less than 23.0 seconds. B: If the time is 23.0 seconds or more and less than 25.0 seconds. If C: 25.0 seconds or longer

[0097] (Mixing speed (integration time (seconds))) When mixing mortar, we measured the time it took from adding water until the mixture was fully combined (integration time). The timing of when the mortar was ready was confirmed by visual observation.

[0098] The integration time (seconds) (mixing speed) of the mortar was evaluated according to the following evaluation criteria (levels). A: If it is less than 140 seconds B: If the time is 140 seconds or more but less than 180 seconds. C: If it is 180 seconds or longer

[0099] (2) Concrete composition: Next, the concrete (concrete composition) was evaluated by measuring the slump flow (cm) and the time to reach a 500 mm flow (seconds) (viscosity, mixing speed, etc.).

[0100] [Slump Flow (cm)] The concrete composition immediately after mixing was measured in accordance with JIS A 1150.

[0101] (viscosity) [Time to reach 500mm flow (seconds)] For the concrete composition immediately after mixing, the slump flow and the time to reach a 500 mm flow (seconds) were measured simultaneously in accordance with JIS A 1150 and Annex JA.

[0102] The time (seconds) to reach 500mm flow was evaluated according to the following evaluation criteria (levels). If S: less than 6.5 seconds A: If the time is 6.5 seconds or more and less than 7.0 seconds. B: If the time is 7.0 seconds or more and less than 8.0 seconds. If C: 8.0 seconds or longer

[0103] (Mixing speed (integration time (seconds))) We measured the time it took from adding water to mixing the concrete until it was fully mixed (integration time). The timing of when the concrete was ready was confirmed by visual observation.

[0104] The integration time (seconds) (mixing speed) of concrete was evaluated according to the following evaluation criteria (levels). A: If it is less than 60 seconds B: If the time is 60 seconds or more but less than 80 seconds. C: If 80 seconds or longer

[0105] (result) As shown in Table 7, the hydraulic compositions (mortar, concrete) to which the hydraulic composition dispersant of this embodiment has been added exhibit high dispersibility and reduced viscosity. Furthermore, it can be seen that the time required to mix the hydraulic compositions can be shortened. [Industrial applicability]

[0106] The dispersant for hydraulic compositions of the present invention can be used as a dispersant for hydraulic compositions by adding it to a hydraulic composition. The hydraulic composition of the present invention can be used to produce hydraulic composition hardened bodies such as mortar hardened bodies and concrete hardened bodies.

Claims

1. A polymer (P) having a structural unit (1) formed from a compound represented by the following general formula (1), and a structural unit (2) formed from a compound containing at least one selected from acrylic acid, methacrylic acid, fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, and salts thereof, Ether compounds (A) are compounds obtained by adding 1 to 500 moles of an alkylene oxide with 2 to 4 carbon atoms to 1 mole of a 1 to 4 valent aliphatic alcohol with 2 to 24 carbon atoms, It contains, The mass-average molecular weight of the polymer (P) is 5,000 to 5,000,000. A dispersant for hydraulic compositions, characterized in that the mass ratio (A / P) of the ether compound (A) to the polymer (P) is greater than 0 and 0.25 or less. 【Chemistry 1】 (In general formula (1), X is an alkenyl group having 6 to 24 carbon atoms, AO is an alkylene oxy group having 2 to 4 carbon atoms, n is an integer from 1 to 500, and Y is a hydrogen atom or a hydrocarbon group having 1 to 24 carbon atoms.)

2. The dispersant for hydraulic compositions according to claim 1, wherein the polymer (P) has a mass ratio of the constituent unit (1) to the constituent unit (2) converted to sodium salt (constituent unit (1) / constituent unit (2) converted to sodium salt) of 99 / 1 to 50 / 50.

3. The dispersant for hydraulic compositions according to claim 1, wherein X in the general formula (1) is an alkenyl group having 8 to 18 carbon atoms.

4. The ether compound (A) is a compound obtained by adding 1 to 500 moles of an alkylene oxide having 2 to 4 carbon atoms to 1 mole of a monovalent aliphatic alcohol having 8 to 18 carbon atoms and having an unsaturated bond. The dispersant for hydraulic compositions according to claim 1, wherein the mass ratio of ethylene oxide in the alkylene oxide is 60% by mass or more.

5. The dispersant for hydraulic compositions according to claim 1, wherein the mass ratio (A / P) of the ether compound (A) to the polymer (P) is 0.01 to 0.

20.

6. A hydraulic composition characterized by containing a hydraulic binder, water, and a dispersant for hydraulic compositions according to any one of claims 1 to 5.

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