Dispersant for hydraulic composition, and hydraulic composition

Abstract

Provided is a dispersant for a hydraulic composition, the dispersant having high dispersibility and capable of reducing the viscosity of the hydraulic composition. The dispersant for a hydraulic composition contains: a polymer (P) having a structural unit (1) formed from a compound represented by general formula (1) and a structural unit (2) formed from a compound containing at least one selected from among an acrylic acid, a methacrylic acid, a fumaric acid, a maleic acid, a maleic anhydride, an itaconic acid, an itaconic anhydride, and salts thereof; and an ether compound (A) which is a compound obtained by adding 1-500 moles of a C2-4 alkylene oxide to 1 mole of a monovalent to tetravalent C2-24 aliphatic alcohol, wherein the mass average molecular weight of the polymer (P) is 5000-5000000, and the mass ratio (A / P) of the ether compound (A) to the polymer (P) is more than 0 and 0.25 or less.

Description

Dispersant for hydraulic composition and hydraulic composition

[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.

[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 aggregates of types that were not actively used conventionally (aggregates of inferior quality) is increasing. A hydraulic composition using such aggregates (aggregates of inferior quality compared to river sand, etc.) is known to have high viscosity and poor workability even at a normal water-binder ratio (W / B).

[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.

[0006] Japanese Patent Application Laid-Open No. 20-24751 Chinese Patent Application Publication No. 115010875 Chinese Patent Application Publication No. 115960320

[0007] However, the water-reducing agent described in Patent Document 2 and the admixture described in Patent Document 3 do not yet have a sufficient effect of reducing the viscosity of the hydraulic composition, and there is room for further improvement.

[0008] That is, the development of a dispersant (dispersant for a hydraulic composition) that can further reduce the viscosity of the hydraulic composition (even if aggregates of inferior quality compared to river sand, etc. are used, the viscosity can be further reduced) has been desired.

[0009] In view of the above circumstances, an object of the present invention is to provide a dispersant for a hydraulic composition that has high dispersibility and can reduce the viscosity of the hydraulic composition.

[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 dispersant for hydraulic compositions comprising: 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; 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.

[0012] (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.)

[0013] [2] The polymer (P) is a dispersant for hydraulic compositions according to [1], wherein the 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) is 99 / 1 to 50 / 50.

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

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

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

[0017] [6] A hydraulic composition characterized by containing a hydraulic binder, water, and a dispersant for hydraulic compositions according to any one of [1] to [5] above.

[0018] The dispersant for hydraulic compositions of the present invention exhibits high dispersibility and has the effect of reducing the viscosity of hydraulic compositions.

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

[0020] Embodiments of the present invention will be described below. However, the present invention is not limited to the following embodiments. Therefore, it should be understood that, without departing from the spirit of the present invention, appropriate modifications and improvements may be made to the following embodiments based on the ordinary knowledge of those skilled in the art. In the following examples, unless otherwise stated, % means mass percent and parts means parts by mass.

[0021] (1) Dispersant for hydraulic compositions: The dispersant for hydraulic compositions of the present invention contains 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, 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. 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.

[0022] (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.)

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

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

[0025] (1-1a) Constituent unit (1): 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 of 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): 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 unit (1) / Constituent unit (2) converted to sodium salt) 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 Units (2) converted to Sodium Salts" 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 structural units in addition to the above-mentioned structural units (1) and (2). Examples of such other structural 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 500,000. By setting the mass average molecular weight in such a range, 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 ratio of the polymer (P) in the dispersant for the hydraulic composition is not particularly limited, and can be, for example, 10 to 100% by mass.

[0040] (1-2) Ether compound (A): 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 to tetravalent aliphatic alcohol having 2 to 24 carbon atoms. And the value of the mass ratio (A / P) of this ether compound (A) to the polymer (P) is more than 0 and 0.2 or less. By satisfying such conditions, high dispersibility can be achieved and the viscosity of the hydraulic composition can be reduced.

[0041] Further, the ether compound (A) preferably necessarily contains 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. At this time, the mass ratio of ethylene oxide (alkylene oxide having 2 carbon atoms) in the alkylene oxide is preferably 60% by mass or more, and more preferably 80% by mass or more. By satisfying such conditions, higher dispersibility can be achieved and the viscosity of the hydraulic composition can be further reduced.

[0042] Also, the value of 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 numerical range in such a manner, higher dispersibility can be achieved and the viscosity of the hydraulic composition can be further reduced.

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

[0044] Here, when using an unreacted substance (unreacted ether compound) during the synthesis reaction of the polymer (P) as the ether compound (A) (specifically, a part of the ether compound (A)) as in the former case above, in order to satisfy the above A / P, the synthesis is carried out so that the amount of the unreacted substance (unreacted ether compound) during the synthesis reaction of the polymer (P) does not exceed the upper limit value in the above A / P. For that purpose, a compound forming the structural unit (1) having sufficient purity and a compound forming the structural unit (2) are used, and the polymer (P) is obtained by polymerization using an appropriate method.

[0045] The polymer (P) can be synthesized by a conventionally known method. Examples of the conventionally known method include radical polymerization using water as a solvent, radical polymerization using an organic solvent as a solvent, and solvent-free radical polymerization.

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

[0047] In addition, an accelerator can be used in combination for the synthesis of the polymer (P). Examples of this accelerator include reducing agents such as sodium bisulfite, sodium metabisulfite, Fe(II) salts such as Mohr's salt, sodium hydroxymethanesulfinate dihydrate, ascorbic acid, and amine compounds such as ethylenediamine and glycine.

[0048] [[ID=]5] Incidentally, for the synthesis of the polymer (P), a chain transfer agent can also be used in order to make the mass average molecular weight of the obtained 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. The polymerization temperature is preferably 0°C or higher at the lower limit and 150°C or lower at the upper limit. More preferably, the lower limit is 30°C or higher, 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., AE 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 a dispersant for hydraulic compositions: The dispersant for hydraulic compositions of the present invention can be produced 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., a 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 synthesis reaction of polymer (P). Then, ether compound (A) is added as necessary 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 necessary.

[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 binders: 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, as well as 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 composition: In the hydraulic composition of the present invention, there are no particular restrictions on the content ratio of the dispersant for hydraulic composition of the present invention, and it can be set as appropriate. For example, the content ratio of the dispersant for 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 aggregates, coarse aggregates, 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 effect. 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, a rust inhibitor consisting of nitrites, and so on.

[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, the water / binder ratio can be 20 to 70% by mass.

[0065] (3) Hardened bodies of hydraulic compositions: The hydraulic compositions of the present invention can be hardened to form hardened products. Specifically, these hardened bodies include hardened mortar (hardened mortar), hardened concrete (hardened concrete), and the like.

[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.

[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 1-17 and Comparative Examples 1-3 are shown in Tables 1 and 2 below. Also, 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]

[0070]

[0071]

[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 manufacturing method for polymer (P) in Example 1 was as follows: First, 210.17 g of a compound obtained by adding 50 moles of EO (ethylene oxide) to 95.02 g of tap water and 1 mole of 7-octen-1-ol was charged into a reactor equipped with a thermometer, stirrer, dropping funnel, and nitrogen inlet tube, and dissolved uniformly while stirring. After that, the atmosphere was replaced with nitrogen, and the temperature of the reaction system was maintained at 65°C with 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 manufactured in the same manner as in Manufacturing Example 1, except that the raw materials and reagents were changed to produce the types and content ratios (mass%) of constituent units 1 and 2 shown in Table 4, thereby obtaining polymers (P) for Examples 2 to 17 and Comparative Examples 1 to 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> Apparatus: Shodex GPC-101 (Showa Denko Corporation) Column: OHpak SB-G + SB-804 HQ + SB-802.5 HQ (Showa Denko Corporation) Detector: Differential Refractometer (RI) Eluent: 50 mM sodium nitrate aqueous solution Flow rate: 0.7 mL / min Column temperature: 40°C Sample concentration: Eluent solution with sample concentration of 0.5 wt% Standard substances: Polyethylene oxide, polyethylene glycol

[0079] (Dispersant for hydraulic compositions) 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 so 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 of 20% was prepared by diluting with tap water.

[0080] The HPLC measurement conditions for the reaction mixture are as follows: <Measurement Conditions> Apparatus: Prominence (Shimadzu Corporation) Column: Synergi 4 μm Hydro-RP 80A (Phenomenex) Detector: Differential Refractometer (RI) Eluent: Acetonitrile / 0.1% phosphate exchange aqueous solution = 70 / 30 (vol. %) Flow rate: 1.0 mL / min Column temperature: 55°C Sample concentration: Eluent solution with a sample concentration of 1.0 mass%

[0081]

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

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

[0084] (2-1) Mortar (Mortar Composition): In a temperature-controlled room maintained at 20°C ± 1°C, fine aggregate (land sand from the Oi River system, excluding that which remains 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, and the mixer was operated at low speed for 10 seconds. Then, 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 Co., Ltd.), and water (Gamagori City water supply) were added simultaneously, and the mixer was operated at low speed to stir 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 of them 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]

[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 forced twin-shaft mixer with a nominal capacity of 55 L, each component shown in Table 6 (the addition rate of the dispersant for hydraulic composition is shown in Table 7) was added to the mixer, and the mixture was kneaded for 90 seconds to prepare 30 L 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 of the concrete composition immediately after mixing was measured in accordance with JIS A 1128.

[0090]

[0091] In Table 6, "W" indicates Gamagori City tap water. "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. "FA" is equivalent to fly ash JIS type II (manufactured by Chubu Fly Ash Co., Ltd., density = 2.39 g / cm³). 3 ) indicates. "S" represents the terrestrial sand of the Oi River system (density = 2.60 g / cm³). 3 ) indicates. "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]

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

[0094] (1) Mortar composition: First, the mortar (mortar composition) was evaluated by measuring the mortar flow value (mm).

[0095] [Mortar Flow (mm)] Except for not performing tapping, the mortar flow (mm) immediately after mixing was measured in accordance with JIS R 5201.

[0096] (Viscosity) [J14 Funnel Flow Time (seconds)] Tested in accordance with the "Fluidity Test Method for Filling Mortar" in the Japan Society of Civil Engineers Concrete Standard Specification JSCE-F541.

[0097] The J14 funnel flow time (seconds) (viscosity) was evaluated according to the following evaluation criteria (levels): S: Less than 21.0 seconds A: 21.0 seconds or more, less than 23.0 seconds B: 23.0 seconds or more, less than 25.0 seconds C: 25.0 seconds or more

[0098] (Mixing speed (integration time (seconds))) When mixing mortar, the time from adding water until the mixture is complete (integration time) was measured. The timing of when the mortar was complete was confirmed by visual observation.

[0099] The integration time (seconds) (mixing speed) of mortar was evaluated according to the following evaluation criteria (levels): A: Less than 140 seconds B: 140 seconds or more, but less than 180 seconds C: 180 seconds or more

[0100] (2) Concrete composition: Next, the concrete (concrete composition) was evaluated by measuring the slump flow (cm) and the time to reach 500 mm flow (seconds) (viscosity, mixing speed, etc.).

[0101] [Slump Flow (cm)] Measured in accordance with JIS A 1150 for the concrete composition immediately after mixing.

[0102] (Viscosity) [Time to reach 500 mm flow (seconds)] For the concrete composition immediately after mixing, the slump flow and the time to reach 500 mm flow (seconds) were measured simultaneously in accordance with Annex JA, in accordance with JIS A 1150.

[0103] The time (seconds) to reach 500 mm flow was evaluated according to the following criteria (levels): S: Less than 6.5 seconds A: 6.5 seconds or more, less than 7.0 seconds B: 7.0 seconds or more, less than 8.0 seconds C: 8.0 seconds or more

[0104] (Mixing speed (integration time (seconds)) When mixing concrete, the time from adding water until the mixture is complete (integration time) was measured. The timing of when the concrete was complete was confirmed by visual observation.

[0105] The integration time (seconds) (mixing speed) of concrete was evaluated according to the following evaluation criteria (levels): A: Less than 60 seconds B: 60 seconds or more, but less than 80 seconds C: 80 seconds or more

[0106] (Results) As shown in Table 7, the hydraulic compositions (mortar, concrete) to which the hydraulic composition dispersant of this example was added exhibited high dispersibility and reduced viscosity. Furthermore, it was found that the time required to mix the hydraulic compositions could be shortened.

[0107] 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 dispersant for hydraulic compositions comprising: 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; 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. (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 dispersant for hydraulic compositions according to claim 1, wherein 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, and 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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