Dispersant for hydraulic composition and hydraulic composition

Abstract

Provided is a dispersant for hydraulic compositions that has high dispersibility and can reduce the viscosity of the hydraulic composition. [Solution] A dispersant for hydraulic compositions comprising: 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 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 in which 1 to 500 moles of an alkylene oxide having 2 to 4 carbon atoms are added to 1 mole of a mono- to tetrahydric 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 (A / P) of the ether compound (A) to the polymer (P) is greater than 0 and less than or equal to 0.25.

Description

[Technical field]

[0001] The present invention relates to a hydraulic composition dispersant and a hydraulic composition, more particularly to a hydraulic composition dispersant having high dispersibility and capable of reducing the viscosity of the hydraulic composition, and a hydraulic composition. [Background technology]

[0002] Conventionally, dispersants for hydraulic compositions have the function of imparting fluidity to hydraulic compositions such as concrete (see, for example, Patent Document 1).

[0003] Known examples of dispersants for hydraulic compositions include naphthalene-based compounds and polycarboxylic acid-based compounds.

[0004] Furthermore, in recent years, with the depletion of high-quality aggregates such as river sand, the proportion of aggregates (inferior quality aggregates) that have not been actively used in the past is increasing. It is known that hydraulic compositions using such aggregates (inferior quality aggregates compared to river sand, etc.) have high viscosity even at normal water-binder ratios (W / B), resulting in poor workability.

[0005] In view of this situation, substances that reduce the viscosity of hydraulic compositions (water-reducing agents, admixtures) have been reported, as in Patent Documents 2 and 3. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2021-24751 [Patent Document 2] China Patent Application Publication No. 115010875 [Patent Document 3] China Patent Application Publication No. 115960320 Summary of the Invention [Problem 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 are still insufficient in terms of the effect of reducing the viscosity of a hydraulic composition, and there is room for further improvement.

[0008] In other words, there has been a demand for the development of a dispersant (dispersant for hydraulic compositions) that can further reduce the viscosity of hydraulic compositions (even if aggregate of inferior quality compared to river sand, etc. is used, the viscosity can be further reduced).

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

[0010] As a result of intensive research to solve the above problems, the present inventors have found that the above problems can be solved by using a specified polymer and a specified ether compound and setting the ratio thereof (specified ether compound / specified polymer) within a specified range. According to the present invention, the following hydraulic composition dispersant and hydraulic composition are provided.

[0011] [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; an ether compound (A) which is a compound in which 1 to 500 moles of an alkylene oxide having 2 to 4 carbon atoms are added to 1 mole of a monohydric to tetrahydric aliphatic alcohol having 2 to 24 carbon atoms; 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 a mass ratio (A / P) of the ether compound (A) to the polymer (P) is greater than 0 and is 0.25 or less.

[0012] [ka] (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 hydraulic compositions according to [1], wherein the polymer (P) has a mass ratio of the structural unit (1) to the structural unit (2) converted into a sodium salt (the structural unit (1) / the structural unit (2) converted into a sodium salt) of 99 / 1 to 50 / 50.

[0014] [3] The dispersant for hydraulic compositions according to the above [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 monohydric aliphatic alcohol having 8 to 18 carbon atoms and an unsaturated bond, The dispersant for hydraulic compositions according to the above [1], wherein the mass ratio of ethylene oxide in the alkylene oxide is 60 mass% or more.

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

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

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

[0019] The hydraulic composition of the present invention exhibits the effect of reducing viscosity by containing the dispersant for hydraulic compositions of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, the 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 modifications, improvements, etc. can be made to the following embodiments based on the ordinary knowledge of those skilled in the art without departing from the spirit of the present invention. In the following examples, etc., % means % by mass, and parts means parts by mass, unless otherwise specified.

[0021] (1) Dispersant for hydraulic compositions: The dispersant for hydraulic compositions of the present invention contains 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, and an ether compound (A) which is a compound in which 1 to 500 moles of an alkylene oxide having 2 to 4 carbon atoms are added to 1 mole of a mono- to tetrahydric 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 (A / P) of the ether compound (A) to the polymer (P) is more than 0 and not more than 0.25.

[0022] [ka] (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.)

[0023] This hydraulic composition dispersant has high dispersibility and can reduce the viscosity of the hydraulic composition, and can also shorten the time required for the hydraulic composition to be kneaded during preparation.

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

[0025] (1-1a) Building block (1): The structural unit (1) is a structural unit formed from a compound represented by general formula (1), and in particular, X in general formula (1) is an alkenyl group having 6 to 24 carbon atoms. In this way, the 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] The 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 ones are preferred.

[0028] Specific examples of alkenyl groups having 6 to 24 carbon atoms include a hexenyl group, a heptenyl group, an octenyl group, a nonenyl group, a decenyl group, an undecenyl group, a dodecenyl group, a tridecenyl group, a tetradecenyl group, a pentadecenyl group, a hexadecenyl group, a heptadecenyl group, an octadecenyl group, a nonadecenyl group, an icosenyl group, a heneicosenyl group, a docosenyl group, a tricosenyl group, and a tetracosenyl group.

[0029] In the general formula (1), AO is an alkyleneoxy group having 2 to 4 carbon atoms (however, when a plurality of such alkyleneoxy groups are present, one type may be used alone, or two or more types may be used). Among these, an alkyleneoxy group having 2 carbon atoms is preferred.

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

[0031] Y in general formula (1) is a hydrogen atom or a hydrocarbon group having 1 to 24 carbon atoms, 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) Building block (2): The structural unit (2) is a structural 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. A structural unit formed from these specific compounds has high dispersibility and can reduce the viscosity of the hydraulic composition.

[0033] In the general formula (2), it is preferable to contain at least acrylic acid or a salt thereof among acrylic acid, methacrylic acid, fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, and salts thereof. These compounds have higher dispersibility and can further reduce the viscosity of the hydraulic composition.

[0034] (Structural unit (1) / Sodium salt equivalent structural unit (2)) In the polymer (P), the mass ratio of the structural unit (1) to the structural unit (2) converted into a sodium salt (structural unit (1) / structural unit (2) converted into a sodium salt) is preferably 99 / 1 to 50 / 50, more preferably 95 / 5 to 68 / 42. By setting the ratio in this manner, the dispersibility can be further improved and the viscosity of the hydraulic composition can be further reduced.

[0035] The sodium salt conversion in "structural unit (2) converted into sodium salt" can be performed as follows. That is, the conversion is performed assuming that the unsaturated carboxylic acid and the salts thereof in the structural unit (2) are all sodium salts of unsaturated carboxylic acid. For example, structural units formed from acrylic acid are all converted as structural units formed from sodium acrylate, and structural units formed from maleic acid and maleic anhydride are all converted as structural units formed from disodium maleate.

[0036] (1-1c) Other structural units: The polymer (P) may further have other structural units in addition to the above 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, (meth)acrylic acid alkyl ester, (meth)allylsulfonic 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 adjusting the mass average molecular weight to such a range, the polymer has high dispersibility and can reduce the viscosity of the hydraulic composition.

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

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

[0040] (1-2) Ether compound (A): The ether compound (A) is a compound in which 1 to 500 moles of an alkylene oxide having 2 to 4 carbon atoms are added to 1 mole of a monohydric to tetrahydric aliphatic alcohol having 2 to 24 carbon atoms. The mass ratio (A / P) of this ether compound (A) to the polymer (P) is greater than 0 and not greater than 0.25. By satisfying these conditions, the dispersibility is high and the viscosity of the hydraulic composition can be reduced.

[0041] Furthermore, it is preferable that the ether compound (A) necessarily contains a compound in which 1 to 500 moles of an alkylene oxide having 2 to 4 carbon atoms are added to 1 mole of a monohydric aliphatic alcohol having 8 to 18 carbon atoms and having an unsaturated bond, and in this case, the mass ratio of ethylene oxide (alkylene oxide having 2 carbon atoms) in the alkylene oxide is preferably 60 mass% or more, and more preferably 80 mass% or more. By satisfying such conditions, the dispersibility can be further increased and the viscosity of the hydraulic composition can be further reduced.

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

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

[0044] Here, when the unreacted material (unreacted ether compound) in the synthesis reaction of polymer (P) is used as ether compound (A) (specifically, part of ether compound (A)) as in the former case, in order to satisfy the above A / P, the synthesis is performed so that the amount of the unreacted material (unreacted ether compound) in the synthesis reaction of polymer (P) does not exceed the upper limit of the above A / P. To this end, a compound forming structural unit (1) and a compound forming structural unit (2) having sufficient purity are used, and polymerized by an appropriate method to obtain polymer (P).

[0045] The polymer (P) can be synthesized by a conventionally known method, such as 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 in the radical polymerization is not particularly limited as long as it decomposes at the polymerization reaction temperature to generate radicals, such as peroxides such as benzoyl peroxide, hydrogen peroxide, ammonium persulfate, sodium persulfate, and potassium persulfate, and azo compounds such as 2,2'-azobisisobutyronitrile and 2,2'-azobis(2-methylbutyronitrile).

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

[0048] A chain transfer agent may be used to adjust the mass average molecular weight of the resulting polymer (P) to a desired range.

[0049] In the polymerization reaction, polymerization conditions such as polymerization temperature are appropriately determined depending on the polymerization method, solvent, polymerization initiator, and chain transfer agent used, but the lower limit of the polymerization temperature is preferably 0° C. or more, and the upper limit is preferably 150° C. or less. The lower limit is more preferably 30° C. or more, and even more preferably 50° C. or more. The upper limit is more preferably 120° C. or less, and even more preferably 100° C. or less.

[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, set retarding components made of sugars, oxycarboxylates, etc., components having a dispersing action made of sodium lignin sulfonate, etc., AE agents made of anionic surfactants, etc., defoamers made of oxyalkylene compounds, etc., hardening accelerators made of alkanolamines, etc., shrinkage reducers made of polyoxyalkylene alkyl ethers, etc., thickeners made of cellulose ether compounds, etc., preservatives made of isothiazolinone compounds, and rust inhibitors made of nitrites, etc.

[0052] The other dispersant components may be used alone or in combination of two or more.

[0053] (1-4) Method for producing dispersant for hydraulic composition: The hydraulic composition dispersant of the present invention can be produced as follows. First, a polymer (P) is synthesized using a compound forming the structural unit (1) and a compound forming the structural unit (2) as raw materials. At this time, an ether compound (A) (i.e., a compound forming the structural unit (1)) is used as a raw material for the polymer (P), but after the synthesis reaction of the polymer (P), the unreacted ether compound (A) can be used as it is. Then, an ether compound (A) is added as necessary so as to satisfy the desired A / P (the mass ratio of the ether compound (A) to the 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 the polymer (P), or may be different. 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 the dispersant for hydraulic compositions of the present invention.

[0055] Such a hydraulic composition has reduced viscosity by containing the dispersant for hydraulic compositions 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, high early strength Portland cement, and sulfate resistant Portland cement; various types of cement, such as blast furnace cement, fly ash cement, and silica fume cement; and further examples include various types of gypsum, such as anhydrous gypsum, hemihydrate gypsum, and dihydrate gypsum; and combinations of powders having latent hydraulic properties and alkaline stimulants, such as a combination of ground granulated blast furnace slag and calcium hydroxide.

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

[0058] (2-2) Dispersant for hydraulic compositions: In the hydraulic composition of the present invention, the content ratio of the dispersant for hydraulic compositions of the present invention is not particularly limited and can be appropriately set. For example, the content ratio of the dispersant for hydraulic compositions of the present invention can be 0.001 to 3.0 parts by mass in terms of solid content with respect to 100 parts by mass of hydraulic binder.

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

[0060] Examples of fine aggregate include river sand, mountain sand, land sand, sea sand, silica sand, crushed sand, various slag fine aggregates, and the like, but may also include those containing fine particles such as clay.

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

[0062] (2-4) Other composition components: The hydraulic composition of the present invention may further contain other composition components as appropriate within the range in which the effect is not impaired. Examples of such other composition components include setting retarders made of sugars, oxycarboxylates, etc., various water reducing agents, AE agents made of anionic surfactants, etc., antifoaming agents made of oxyalkylene compounds, etc., hardening accelerators made of alkanolamines, etc., shrinkage reducing agents made of polyoxyalkylene alkyl ethers, etc., thickeners made of cellulose ether compounds, preservatives made of isothiazolinone compounds, etc., and rust inhibitors made of nitrites, etc.

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

[0064] In the hydraulic composition of the present invention, the ratio of water to hydraulic binder (water / binder ratio) can be appropriately selected from conventionally known ratios, and can be, for example, 20 to 70 mass %.

[0065] (3) Cured product of hydraulic composition: The hydraulic composition of the present invention can be cured to form a cured product, specifically, a hardened mortar (hardened mortar product), a hardened concrete (hardened concrete product), and the like.

[0066] The hardened body of the hydraulic composition can be produced by a conventionally known method, specifically, a method of filling a formwork with the hydraulic composition and curing it at room temperature or by heating and curing it with steam, etc. EXAMPLES

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

[0068] (Examples 1 to 17, Comparative Examples 1 to 3) (1) Dispersant for hydraulic compositions: First, the compounds (P1-1 to P1-11, P2-1 to P2-4) forming the structural unit 1 and the structural unit 2 constituting the polymer (P) used in the hydraulic composition dispersants of Examples 1 to 17 and Comparative Examples 1 to 3 are shown in the following Tables 1 and 2. The ether compounds (A) (A1-1 to A1-11, A-12 to A-15) are shown in the following Table 3. In Table 3, EO stands for ethylene oxide, and PO stands for propylene oxide.

[0069] [Table 1]

[0070] [Table 2]

[0071] [Table 3]

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

[0073] (Production Example 1) Specifically, in the method for producing the polymer (P) of Example 1, first, 95.02 g of tap water and 210.17 g of a compound obtained by adding 50 moles of EO (ethylene oxide) to 1 mole of 7-octen-1-ol were charged into a reactor equipped with a thermometer, a stirrer, a dropping funnel, and a nitrogen inlet tube, and were 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, 2.30g of 30% hydrogen peroxide solution was charged into the reactor. At the same time, an aqueous solution in which 18.64g of acrylic acid and 0.69g of methacrylic acid were uniformly dissolved in 38.66g of tap water was added dropwise over a period of 3 hours, and at the same time, an aqueous solution in which 0.90g of L-ascorbic acid and 1.15g of 3-mercaptopropionic acid were dissolved in 18.38g of tap water was added dropwise over a period of 3.5 hours. After that, the temperature of the reaction system was maintained at 65°C for 1 hour, and the polymerization reaction was completed.

[0075] Thereafter, a 30% aqueous solution of sodium hydroxide was added to the reaction system so that the pH became 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) Polymer (P) was produced in the same manner as in Production Example 1, except that the raw materials and reagents were changed so that the types and contents (mass%) of structural units 1 and structural units 2 were as shown in Table 4, to produce each of the polymers (P) in Examples 2 to 17 and Comparative Examples 1 to 3.

[0077] The reaction mixture obtained in each Production Example was analyzed by gel permeation chromatography (GPC) under the following measurement conditions. The mass average molecular weight obtained as the analysis result is shown in Table 4.

[0078] <Measurement conditions> Equipment: Shodex GPC-101 (Showa Denko) Column: OHpak SB-G + SB-804 HQ + SB-802.5 HQ (Showa Denko) Detector: Differential refractometer (RI) Eluent: 50mM sodium nitrate aqueous solution Flow rate: 0.7mL / min Column temperature: 40℃ Sample concentration: Eluent solution with sample concentration of 0.5% by weight Standard materials: 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 manufacturing method of polymer (P) 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 reaction mixture and mixed so that the ratio (A / P) of polymer (P) and ether compound (A) satisfied the value shown in Table 4, and the mixture was diluted with tap water to prepare a dispersant for hydraulic compositions with an active ingredient of 20%.

[0080] The HPLC measurement conditions for the reaction mixture are as follows. <Measurement conditions> Equipment: Prominence (Shimadzu Corporation) Column: Synergi 4μm Hydro-RP 80A (Phenomenex) Detector: Differential refractometer (RI) Eluent: acetonitrile / 0.1% phosphate ion 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, concrete) were prepared using each of the prepared hydraulic composition dispersants.

[0084] (2-1) Mortar (mortar composition): In a thermostatic room controlled at 20°C±1°C, fine aggregate (land sand from the Oi River basin, excluding that which was retained 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 to mix for 10 seconds. Then, a predetermined amount of additive (dispersant for hydraulic composition) (the addition rate of dispersant for hydraulic composition is shown in Table 7), 0.1 g of antifoaming agent (AFK-2, manufactured by Takemoto Oil & Fat), and water (Gamagori City waterworks) were added at the same time, and the mixer was operated at low speed to mix each component, and the components were kneaded for 210 seconds to obtain a mortar composition. When the temperature of the obtained mortar composition was confirmed, the temperature of all of the mortar compositions was 20°C±1°C. The additive and antifoaming agent were considered to be 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 (a mixture of equal parts of Taiheiyo Cement, UBE Mitsubishi Cement, and Sumitomo Osaka Cement, density = 3.04 g / cm 3 ), and "S" stands for Oigawa River land sand (density = 2.60g / cm 3 ) is shown.

[0087] (2-2) Concrete (concrete composition): A forced twin-shaft mixer with a nominal capacity of 55 L was used, and the components shown in Table 6 (the addition rates of the hydraulic composition dispersants are shown in Table 7) were added to the mixer, followed by mixing for 90 seconds to prepare 30 L of a concrete composition.

[0088] The air content in the prepared concrete composition was adjusted by using an antifoaming agent (product name AFK-2 manufactured by Takemoto Yushi) at 0.001% by mass 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. Each dispersant and antifoaming agent was used as part of the water.

[0089] [Air volume (%)] The air content was measured in accordance with JIS A 1128 with respect to the air content of 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 (a mixture of equal parts of Taiheiyo Cement, UBE Mitsubishi Cement, and Sumitomo Osaka Cement, density = 3.04 g / cm 3 ), and "FA" is fly ash equivalent to JIS II type (manufactured by Chubu Fly Ash Co., Ltd., density = 2.39 g / cm 3 ), and "S" stands for Oigawa River land sand (density = 2.60g / cm 3 ), and "G" stands for crushed stone from Okazaki (density = 2.66 g / cm 3 "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 carried out on the 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). [Mortar flow (mm)] The mortar flow (mm) immediately after mixing was measured in accordance with JIS R 5201, except that tapping was not performed.

[0095] (viscosity) [J14 funnel flow time (seconds)] The test was conducted in accordance with the "Test method for fluidity of 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). S: Less than 21.0 seconds A: 21.0 seconds or more and less than 23.0 seconds B: 23.0 seconds or more and less than 25.0 seconds C: If it is 25.0 seconds or more

[0097] (Mixing speed (integration time (seconds))) When mixing the mortar, the time from adding water to mixing the mortar (integration time) was measured. The timing of the mortar being mixed 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: Less than 140 seconds B: 140 seconds or more but less than 180 seconds C: If it is more than 180 seconds

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

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

[0101] (viscosity) [500mm flow arrival time (sec)] Immediately after mixing, the concrete composition was measured for slump flow in accordance with JIS A 1150 and at the same time, the time to reach 500 mm flow (seconds) in accordance with Appendix JA.

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

[0103] (Mixing speed (integration time (seconds)) When mixing the concrete, the time from adding water to when the concrete was mixed (integration time) was measured. The timing of when the concrete was mixed was confirmed by visual observation.

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

[0105] (result) As shown in Table 7, it is understood that the hydraulic composition (mortar, concrete) to which the hydraulic composition dispersant of this Example is added has high dispersibility and reduced viscosity. Furthermore, it is also understood that the time required for the hydraulic composition to be mixed can be shortened. [Industrial Applicability]

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

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; an ether compound (A) which is a compound in which 1 to 500 moles of an alkylene oxide having 2 to 4 carbon atoms is added to 1 mole of a monohydric to tetrahydric aliphatic alcohol having 2 to 24 carbon atoms; Contains The weight average molecular weight of the polymer (P) is 5,000 to 5,000,000; A dispersant for hydraulic compositions, characterized in that a mass ratio (A / P) of the ether compound (A) to the polymer (P) is greater than 0 and is 0.25 or less. 【Chemistry 1】 (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.)

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

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

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

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

20.

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

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