Additive for hydraulic composition and hydraulic composition

Abstract

This allows for further improvement in the compressive strength of the hydraulic composition at 28 days of age. [Solution] The additive for hydraulic compositions according to the present invention is characterized by containing tertiary alkanolamines (A), a dihydric to tetrahydric polyalcohol (B) that contains neither an amino group nor a carboxy group, and primary alkanolamines (C).

Description

[Technical Field]

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

[0002] Hydraulic compositions are compositions containing a binder such as cement. For example, concrete is a hydraulic composition obtained by mixing cement, aggregate, and water, and the hardened concrete is widely used as a building material.

[0003] Additives for hydraulic compositions are used to improve the strength of hydraulic compositions after hardening. For example, additives generally called water-reducing agents increase the dispersibility of cement in water, thereby reducing the unit water content of the hydraulic composition, thereby contributing to improving the strength of the hydraulic composition after hardening.

[0004] For example, Japanese Patent Laid-Open Publication No. 2018-140920 (Patent Document 1) discloses a cement additive containing at least one selected from triisopropanolamine, N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine, and N,N-bis(2-hydroxypropyl)-N-(hydroxyethyl)amine, and at least one selected from oxycarboxylic acid or a salt thereof, keto acid or a salt thereof, sugar, and sugar alcohol. The cement additive described in Patent Document 1 can significantly improve the strength of the hardened cement composition over a long period of time. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-140920 Summary of the Invention [Problem to be solved by the invention]

[0006] However, even when the cement additive described in Patent Document 1 is used, the long-term strength of concrete (compressive strength at an age of 28 days) may be insufficient in some cases.

[0007] Therefore, it is desired to realize an additive for a hydraulic composition and a hydraulic composition that can further improve the compressive strength of the hydraulic composition at an age of 28 days. [Means for solving the problem]

[0008] The additive for hydraulic compositions according to the present invention comprises: Contains at least one compound selected from the group consisting of triisopropanolamine and N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine Tertiary alkanolamines (A) and polyhydric alcohols (B) with a hydric or tetrahydric alcohol content that does not contain either amino or carboxyl groups. (B) a polyhydric alcohol containing at least one compound selected from the group consisting of diethylene glycol and glycerin; and, Contains a compound represented by formula (1) Contains primary alkanolamines (C) and death, [ka] In formula (1), R represents a group selected from the group consisting of a hydrogen atom, a methyl group, an ethyl group, a propyl group, a hydroxymethyl group, a 1-hydroxyethyl group, and a 2-hydroxyethyl group; one of X and Y represents an amino group and the other represents a hydroxy group; and the proportion of the content of the tertiary alkanolamines (A) relative to the total content of the tertiary alkanolamines (A), the polyhydric alcohol (B), and the primary alkanolamines (C) is 30% by mass or more and 70% by mass or less, the proportion of the content of the polyhydric alcohol (B) is 20% by mass or more and 60% by mass or less, and the proportion of the content of the primary alkanolamines (C) is 10% by mass or more and 40% by mass or less. It is characterized by:

[0009] The hydraulic composition according to the present invention is characterized by containing cement, water, a dispersant, and the additive for hydraulic compositions described above.

[0010] The present inventors have discovered that tertiary alkanolamines (A), a dihydric to tetrahydric polyhydric alcohol (B) containing neither an amino group nor a carboxy group, and primary alkanolamines (C) have a synergistic effect in improving the strength of a hydraulic composition, and have thus completed the present invention. The above-mentioned configurations enable further improvement in the compressive strength of the hydraulic composition at an age of 28 days.

[0011] Preferred embodiments of the present invention will be described below, but the scope of the present invention is not limited to the preferred embodiments described below.

[0012] In one embodiment, the additive for hydraulic compositions according to the present invention preferably further contains at least one component selected from the group consisting of an organic sulfur compound (D) containing at least one compound selected from the group consisting of a dialkyl sulfone and a dialkyl sulfoxide, and a carbonate ester compound (E).

[0013] In one embodiment, the additive for hydraulic compositions according to the present invention preferably contains the organic sulfur compound (D) and the carbonate ester compound (E).

[0014] In one embodiment of the additive for hydraulic compositions according to the present invention, the organic sulfur compound (D) preferably contains dimethyl sulfone.

[0015] In one embodiment of the additive for hydraulic compositions according to the present invention, the carbonate ester compound (E) preferably contains glycerol 1,2-carbonate.

[0016] In one aspect, the additive for hydraulic compositions according to the present invention is such that, relative to the total content of the tertiary alkanolamines (A), the polyhydric alcohol (B), the primary alkanolamines (C), the organic sulfur compound (D), and the carbonate ester compound (E), the content of the tertiary alkanolamines (A) is from 20% to 50% by mass, the content of the polyhydric alcohol (B) is from 20% to 50% by mass, the content of the primary alkanolamines (C) is from 15% to 40% by mass, the content of the organic sulfur compound (D) is from 0% to 20% by mass, and the content of the carbonate ester compound (E) is from 0% to 20% by mass, and at least one of the content of the organic sulfur compound (D) and the content of the carbonate ester compound (E) is greater than 0% by mass.

[0017] According to the above-mentioned preferred embodiments, the compressive strength of the hydraulic composition at 28 days is likely to be particularly high. In the present invention, it is permissible for any two or more of the above-mentioned preferred embodiments to be simultaneously satisfied, as long as they are not inconsistent with each other.

[0018] Further features and advantages of the present invention will become more apparent from the following description of illustrative and non-limiting embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0019] An embodiment of the additive for hydraulic compositions and the hydraulic composition according to the present invention will be described.

[0020] [Configuration of additive for hydraulic composition] The hydraulic composition additive according to this embodiment contains tertiary alkanolamines (A), a dihydric to tetrahydric polyhydric alcohol (B) containing neither an amino group nor a carboxy group, and primary alkanolamines (C). The hydraulic composition additive according to this embodiment also optionally contains one or both of an organic sulfur compound (D) and a carbonate ester compound (E). The hydraulic composition additive preferably contains at least one component selected from the group consisting of the organic sulfur compound (D) and the carbonate ester compound (E), and more preferably contains both the organic sulfur compound (D) and the carbonate ester compound (E).

[0021] The tertiary alkanolamines (A) are not limited as long as they are compounds that fall under the category of tertiary alkanolamines. The tertiary alkanolamines (A) may be a single compound or multiple compounds. The tertiary alkanolamines (A) preferably contain at least one compound selected from the group consisting of triisopropanolamine, N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine, and N,N-bis(2-hydroxypropyl)-N-(hydroxyethyl)amine, and more preferably contain at least one compound selected from the group consisting of triisopropanolamine and N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine.

[0022] The polyhydric alcohol (B) is not limited as long as it is a compound corresponding to a dihydric to tetrahydric polyhydric alcohol that does not contain either an amino group or a carboxy group. The polyhydric alcohol (B) may be a single compound or a plurality of compounds. The polyhydric alcohol (B) preferably contains at least one compound selected from the group consisting of diethylene glycol, glycerin, and diglycerin, and more preferably contains at least one compound selected from the group consisting of diethylene glycol and glycerin.

[0023] The primary alkanolamines (C) are not limited as long as they are compounds that fall under the category of primary alkanolamines. The primary alkanolamines (C) may be a single compound or a plurality of compounds. The primary alkanolamines (C) preferably include a compound represented by formula (1). [ka] In formula (1), R is a group selected from the group consisting of a hydrogen atom, a methyl group, an ethyl group, a propyl group, a hydroxymethyl group, a 1-hydroxyethyl group, and a 2-hydroxyethyl group. In formula (1), one of X and Y is an amino group and the other is a hydroxy group.

[0024] Non-limiting examples of compounds represented by formula (1) include trishydroxymethylaminomethane (R is a hydroxymethyl group, X is an amino group, and Y is a hydroxy group), 2-amino-2-ethyl-1,3-propanediol (R is an ethyl group, X is an amino group, and Y is a hydroxy group), 2-amino-1,3-propanediol (R is a hydrogen atom, X is an amino group, and Y is a hydroxy group), 3-amino-1,2-propanediol (R is a hydrogen atom, X is a hydroxy group, and Y is an amino group), and 2-amino-2-methyl-1,3-propanediol (R is a methyl group, X is an amino group, and Y is a hydroxy group).

[0025] When the hydraulic composition additive according to this embodiment contains an organic sulfur compound (D), the organic sulfur compound (D) contains at least one compound selected from the group consisting of dialkyl sulfones and dialkyl sulfoxides. The organic sulfur compound (D) may be a single compound or multiple compounds. When the organic sulfur compound (D) contains multiple compounds, it is sufficient that at least one compound is selected from the group consisting of dialkyl sulfones and dialkyl sulfoxides. The organic sulfur compound (D) may contain an organic sulfur compound other than dialkyl sulfones and dialkyl sulfoxides. The organic sulfur compound (D) preferably contains a dialkyl sulfone, more preferably contains at least one compound selected from the group consisting of dimethyl sulfone and diethyl sulfone, and even more preferably contains dimethyl sulfone.

[0026] When the additive for hydraulic compositions according to this embodiment contains a carbonate ester compound (E), the carbonate ester compound (E) is not limited as long as it is a compound corresponding to a carbonate ester compound. The carbonate ester compound (E) may be a single compound or a plurality of compounds. The carbonate ester compound (E) preferably contains at least one compound selected from the group consisting of glycerol 1,2-carbonate, ethylene carbonate, and propylene carbonate, and more preferably contains glycerol 1,2-carbonate.

[0027] The additive for hydraulic compositions according to this embodiment may contain other components, such as tertiary alkanolamines (A), polyhydric alcohols (B), primary alkanolamines (C), organic sulfur compounds (D), and carbonate ester compounds (E). Examples of such other components include, but are not limited to, dispersants, strength enhancers, setting retarders, air-entraining agents (also known as air-entraining agents), antifoaming agents, shrinkage-reducing agents, thickeners, preservatives, and rust inhibitors. The additive for hydraulic compositions may be appropriately diluted with water (tap water, industrial water, ion-exchanged water, distilled water, etc.).

[0028] In the additive for hydraulic compositions according to this embodiment, it is preferred that the proportion of the tertiary alkanolamines (A) is 30% by mass or more and 70% by mass or less, the proportion of the polyhydric alcohol (B) is 20% by mass or more and 60% by mass or less, and the proportion of the primary alkanolamines (C) is 10% by mass or more and 40% by mass or less, relative to the total content of the tertiary alkanolamines (A), the polyhydric alcohol (B), and the primary alkanolamines (C). When one or more of the tertiary alkanolamines (A), the polyhydric alcohol (B), and the primary alkanolamines (C) contain multiple compounds, the content of that component refers to the total content of the multiple compounds corresponding to that component.

[0029] When the hydraulic composition additive according to this embodiment contains at least one component selected from the group consisting of an organic sulfur compound (D) and a carbonate ester compound (E), it is preferred that, relative to the total content of the tertiary alkanolamines (A), the polyhydric alcohol (B), the primary alkanolamines (C), the organic sulfur compound (D), and the carbonate ester compound (E), the content of the tertiary alkanolamines (A) is from 20 to 50 mass%; the content of the polyhydric alcohol (B) is from 20 to 50 mass%; the content of the primary alkanolamines (C) is from 15 to 40 mass%; the content of the organic sulfur compound (D) is from 0 to 20 mass%; and the content of the carbonate ester compound (E) is from 0 to 20 mass%. However, at least one of the content of the organic sulfur compound (D) and the content of the carbonate ester compound (E) is greater than 0 mass%. In addition, when one or more of the components of the tertiary alkanolamines (A), polyhydric alcohols (B), primary alkanolamines (C), organic sulfur compounds (D), and carbonate ester compounds (E) contain multiple compounds, the content of the component refers to the total content of the multiple compounds corresponding to the component.

[0030] [Method for producing additives for hydraulic compositions] The additive for hydraulic compositions according to this embodiment can be obtained by mixing tertiary alkanolamines (A), polyhydric alcohols (B), primary alkanolamines (C), optionally added organic sulfur compounds (D) and carbonate ester compounds (E), and optionally added other components, by a known method.

[0031] [Hydraulic composition] The hydraulic composition according to this embodiment contains cement, water, a dispersant, and the additive for hydraulic compositions described above. The hydraulic composition according to this embodiment may also contain a binder and an aggregate other than cement.

[0032] The cement contained in the hydraulic composition according to this embodiment is not particularly limited. Non-limiting examples of cement include various Portland cements such as ordinary Portland cement, moderate-heat Portland cement, low-heat Portland cement, high-early-strength Portland cement, and sulfate-resistant Portland cement, as well as blast-furnace cement, fly ash cement, and silica fume cement.

[0033] The water contained in the hydraulic composition according to the present embodiment is not particularly limited, and may be tap water, industrial water, ion-exchanged water, distilled water, or the like, but is not limited to these.

[0034] The dispersant contained in the hydraulic composition according to this embodiment may be a known dispersant used in hydraulic compositions. Non-limiting examples of such dispersants include polycarboxylic acid copolymers, phosphate ester copolymers, naphthalene condensates, melamine condensates, phenol condensates, and lignin sulfonates. The dispersant preferably contains a polycarboxylic acid polymer. Commercially available dispersants may also be used. Examples of commercially available dispersants include water reducing agents, air-entraining water reducing agents, high-performance water reducing agents, and high-performance air-entraining water reducing agents.

[0035] The hydraulic composition according to this embodiment may contain a binder other than cement, such as fly ash, ground granulated blast furnace slag, ground limestone, stone powder, silica fume, and an expansive agent.

[0036] The hydraulic composition according to this embodiment may contain aggregate. Non-limiting examples of fine aggregate among aggregates include river sand, mountain sand, land sand, sea sand, silica sand, crushed sand, and various slag fine aggregates. The fine aggregate may also contain fine particles such as clay. Non-limiting examples of coarse aggregate among aggregates include river gravel, mountain gravel, land gravel, crushed stone, various slag coarse aggregates, and lightweight aggregate.

[0037] The hydraulic composition according to this embodiment may contain components other than those described above. Examples of such other components include, but are not limited to, strength enhancers, setting retarders, air-entraining agents (also referred to as AE agents), antifoaming agents, shrinkage-reducing agents, thickeners, preservatives, and rust inhibitors. These components may also be included in additives for hydraulic compositions. That is, any of the components exemplified above may be added as components of additives for hydraulic compositions, or may be added as components separate from the additives for hydraulic compositions in the stage of producing the hydraulic composition.

[0038] The hydraulic composition according to this embodiment may contain the additive for hydraulic compositions in an amount of 0.01% by mass or more and 0.5% by mass or less relative to the cement-containing binder. More preferably, the additive for hydraulic compositions may be contained in an amount of 0.05% by mass or more and 0.2% by mass or less relative to the cement-containing binder. The content of the additive for hydraulic compositions used in calculating the content ratio of the additive for hydraulic compositions relative to the cement-containing binder is the content of non-volatile components. The non-volatile components of the additive for hydraulic compositions refer to components that remain without volatilization after the additive for hydraulic compositions is heated in a hot air dryer at 105°C for 2 hours.

[0039] Other blending conditions for the hydraulic composition according to this embodiment may be within known blending conditions for hydraulic compositions. For example, the ratio of water to binder containing cement (W / B) may be 20% by mass or more and 70% by mass or less.

[0040] A hardened product can be obtained from the hydraulic composition according to this embodiment by a normal application method, i.e., filling a formwork with the hydraulic composition and curing it at room temperature or by heat curing with steam to obtain hardened mortar, concrete, etc.

[0041] The hydraulic composition according to this embodiment contains the additive for hydraulic compositions described above, which allows it to have higher strength than compositions containing conventional additives for hydraulic compositions. The inventors have also discovered that hydraulic compositions containing an additive for hydraulic compositions containing all of tertiary alkanolamines (A), polyhydric alcohols (B), and primary alkanolamines (C) exhibit a level of strength improvement that exceeds the combined contribution of each component. In other words, the tertiary alkanolamines (A), polyhydric alcohols (B), and primary alkanolamines (C) can be said to have a synergistic effect in improving the strength of the hydraulic composition.

[0042] Other Embodiments The present invention can be an additive for hydraulic compositions, characterized by containing tertiary alkanolamines (A), a dihydric to tetrahydric polyalcohol (B), and primary alkanolamines (C).

[0043] In one embodiment, the additive for hydraulic compositions may be such that the tertiary alkanolamines (A) include at least one compound selected from the group consisting of triisopropanolamine and N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine.

[0044] In one embodiment of the additive for hydraulic compositions, the polyhydric alcohol (B) may include at least one compound selected from the group consisting of diethylene glycol and glycerin.

[0045] In one embodiment, the additive for hydraulic compositions comprises the primary alkanolamines (C) containing a compound represented by formula (1): [ka] In formula (1), R is a group selected from the group consisting of a hydrogen atom, a methyl group, an ethyl group, a propyl group, a hydroxymethyl group, a 1-hydroxyethyl group, and a 2-hydroxyethyl group, and one of X and Y can be an amino group and the other a hydroxy group.

[0046] In one embodiment, the additive for hydraulic compositions may be such that, relative to the total content of the tertiary alkanolamines (A), the polyhydric alcohol (B), and the primary alkanolamines (C), the content of the tertiary alkanolamines (A) is 30% by mass or more and 70% by mass or less, the content of the polyhydric alcohol (B) is 20% by mass or more and 60% by mass or less, and the content of the primary alkanolamines (C) is 10% by mass or more and 40% by mass or less.

[0047] Regarding other configurations, it should be understood that the embodiments disclosed in this specification are illustrative in all respects and that the scope of the present invention is not limited thereby. Those skilled in the art will easily understand that appropriate modifications are possible without departing from the spirit of the present invention. Therefore, other embodiments modified without departing from the spirit of the present invention are naturally included in the scope of the present invention. [Example]

[0048] The present invention will be further described below with reference to examples, but the present invention is not limited to these examples.

[0049] [Preparation of additive for hydraulic composition] The following methods were used to prepare the examples shown in Tables 1 and 2 below. 1~31, Reference examples 1~8, And additives for hydraulic compositions of Comparative Examples 1 to 14 were obtained.

[0050] (1) Raw materials (1-1) Tertiary alkanolamines The following tertiary alkanolamines were used: Tertiary alkanolamines A-1, A-2, and A-3 all correspond to the tertiary alkanolamine (A) according to the above embodiment. A-1: Triisopropanolamine (Fujifilm Wako Pure Chemical Industries, Ltd.) A-2: N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine (Tokyo Chemical Industry Co., Ltd.) A-3: N,N-bis(2-hydroxypropyl)-N-(hydroxyethyl)amine (Tokyo Chemical Industry Co., Ltd.)

[0051] (1-2) Alcohol The following alcohols were used. Alcohols B-1, B-2, and B-3 are dihydric to tetrahydric polyhydric alcohols, and correspond to the polyhydric alcohol (B) according to the above embodiment. Alcohols b-1, b-2, and b-3 do not correspond to the polyhydric alcohol (B) according to the above embodiment. B-1: Glycerin (Fujifilm Wako Pure Chemical Industries, Ltd.) B-2: Diethylene glycol (Fujifilm Wako Pure Chemical Industries, Ltd.) B-3: Diglycerin (Fujifilm Wako Pure Chemical Industries, Ltd.) b-1: Sodium gluconate (Fujifilm Wako Pure Chemical Industries, Ltd.) b-2: Tartaric acid (Fujifilm Wako Pure Chemical Industries, Ltd.) b-3: Malic acid (Fujifilm Wako Pure Chemical Industries, Ltd.)

[0052] (1-3) Primary alkanolamines The following primary alkanolamines were used. Primary alkanolamines C-1, C-2, C-3, C-4, and C-5 all correspond to the compounds represented by formula (1) among the primary alkanolamines (C) according to the above embodiment. [ka] C-1: Trishydroxymethylaminomethane (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) (R is a hydroxymethyl group, X is an amino group, and Y is a hydroxy group.) C-2: 2-amino-2-ethyl-1,3-propanediol (R is an ethyl group, X is an amino group, and Y is a hydroxy group). C-3: 2-amino-1,3-propanediol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) (R is a hydrogen atom, X is an amino group, and Y is a hydroxy group.) C-4: 3-amino-1,2-propanediol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) (R is a hydrogen atom, X is a hydroxy group, and Y is an amino group.) C-5: 2-amino-2-methyl-1,3-propanediol (Fujifilm Wako Pure Chemical Industries, Ltd.) (R is a methyl group, X is an amino group, and Y is a hydroxy group.)

[0053] (1-4)Organic sulfur compounds The following organic sulfur compounds were used: Both organic sulfur compounds D-1 and D-2 correspond to the organic sulfur compound (D) according to the above embodiment. D-1: Dimethyl sulfone (Fujifilm Wako Pure Chemical Industries, Ltd.) D-2: Diethyl sulfone (Fujifilm Wako Pure Chemical Industries, Ltd.)

[0054] (1-5) Carbonate ester compounds The following carbonate ester compounds were used: Carbonate ester compounds E-1, E-2, and E-3 all correspond to the carbonate ester compound (E) according to the above embodiment. E-1: Glycerol 1,2-carbonate (Fujifilm Wako Pure Chemical Industries, Ltd.) E-2: Ethylene carbonate (Fujifilm Wako Pure Chemical Industries, Ltd.) E-3: Propylene carbonate (Fujifilm Wako Pure Chemical Industries, Ltd.)

[0055] (2) Preparation of additives for hydraulic compositions The components were mixed so as to obtain the proportions shown in Tables 1 and 2, and diluted with ion-exchanged water to prepare an aqueous solution containing 20% ​​by mass of the active ingredient.

[0056] [Evaluation of additives for hydraulic compositions] (1) Preparation of hydraulic composition (1-1) Raw materials for hydraulic compositions The water used was tap water from Gamagori City. The cement used was ordinary Portland cement. The ordinary Portland cement was a mixture of equal parts of ordinary Portland cement manufactured by Taiheiyo Cement Corporation, UBE Mitsubishi Cement Corporation, and Sumitomo Osaka Cement Co., Ltd., and had a density of 3.16 g / cm. 3 The fine aggregate used was land sand from the Oi River basin. The density of the land sand was 2.57 g / cm 3 Crushed stone from Okazaki was used as coarse aggregate. The density of the crushed stone was 2.68 g / cm 3 It was.

[0057] (1-2) Preparation of hydraulic composition In a test room at 20°C, a binder made of ordinary Portland cement, land sand and crushed stone as aggregates were charged into a 50 L pan-type forced mixing mixer. , reference example, The hydraulic composition additives of either of the comparative examples, a high-performance AE water-reducing agent (Chupol HP-11 (Takemoto Yushi Co., Ltd.)) mainly containing a polycarboxylic acid-based dispersant, and water containing an antifoaming agent (AFK-2 (Takemoto Yushi Co., Ltd.)) were added to a mixer and kneaded for 90 seconds to obtain a hydraulic composition. The obtained hydraulic composition was at 20°C. The unit amount of each component was 165 kg / m of water. 3 , cement 367 kg / m 3 , fine aggregate 875kg / m 3, coarse aggregate 961kg / m 3 Under these unit quantity conditions, the fine aggregate ratio was 48.5%, and the ratio of water to cement (W / C) was 45%. The amount of additive for hydraulic composition (non-volatile content) was set to 0.06% by mass or more and 0.10% by mass or less relative to the cement, the amount of high-performance AE water-reducing agent was set to 0.8% by mass relative to the cement, and the amount of antifoaming agent was set to 0.0002% by mass relative to the cement, and these components were added as part of the mixing water.

[0058] The slump flow of the obtained hydraulic composition was measured in accordance with JIS A 1150:2020. , reference example, In both the examples and the comparative examples, the slump flow was in the range of 420 mm±10 mm. The air content of the obtained hydraulic compositions was measured in accordance with JIS A 1128:2020. , reference example, In both the Examples and Comparative Examples, the air content was 2.0% or less. , reference example, Since the slump flow and air content were equivalent in each example of the hydraulic compositions of the Examples and Comparative Examples, the influence of these factors can be eliminated when comparing the strength of the hydraulic compositions of each example. In other words, experimental conditions were established that allowed for the investigation of differences in strength due to differences in additives for hydraulic compositions.

[0059] (2) Compressive strength test at 28 days The hydraulic composition prepared by the above procedure was filled into a φ100mm x 200mm steel formwork to prepare a test specimen, which was then subjected to constant temperature and humidity air curing for 24 hours in an environment of 20°C temperature and 60% humidity. Subsequently, the test specimen was cured in water at 20°C for 27 days. After a total of 28 days of curing, the test specimen was removed from the formwork, the surface was polished, and the compressive strength was measured in accordance with JIS A 1108:2018 using an automatic compressive strength measuring instrument (manufactured by Mayekawa Manufacturing Co., Ltd.). Examples , reference example, The measured values ​​of the compressive strength of each example and comparative example were expressed as a percentage, with the measured value of the compressive strength of Comparative Example 1, which did not contain any additive for hydraulic compositions, being taken as 100%, and this was taken as the "strength ratio." , reference example, The examples and comparative examples were classified into the following four levels A to D. A: The strength ratio is 115% or more. B: The intensity ratio is 110% or more and less than 115%. C: The intensity ratio is 105% or more and less than 110%. D: The intensity ratio is less than 105%.

[0060] 〔result〕 Example , reference example, For each of the examples and comparative examples, the types and ratios (mass%) of raw materials, the amount of additive for hydraulic compositions added (mass% relative to cement), slump flow and air content, compressive strength and strength ratio at 28 days (percentage relative to Comparative Example 1), and evaluations (A to D) are shown in Tables 1 and 2. In the tables, the tertiary alkanolamines (A), polyhydric alcohols (B), primary alkanolamines (C), organic sulfur compounds (D), and carbonate ester compounds (E) are abbreviated by their respective symbols only.

[0061] Example 1 31 and Reference Examples 1 to 8 As shown in Figure 1, when the additive for hydraulic compositions containing tertiary alkanolamines (A), polyhydric alcohols (B), and primary alkanolamines (C) was used, a strength increase of 5% or more was observed compared to Comparative Example 1, in which no additive for hydraulic compositions was added. The remarkable increase in strength observed in the Examples is not observed when tertiary alkanolamines (A), polyhydric alcohols (B), or primary alkanolamines (C) are used alone, and is at a level that cannot be explained by simply adding up the contributions to strength when tertiary alkanolamines (A), polyhydric alcohols (B), or primary alkanolamines (C) are used alone. In other words, it is believed that the tertiary alkanolamines (A), polyhydric alcohols (B), and primary alkanolamines (C) act synergistically to contribute to the improvement in strength of the hydraulic composition.

[0062] In addition, the increase in strength of the hydraulic composition is more remarkable when an additive for hydraulic compositions containing at least one of the organic sulfur compound (D) and the carbonate ester compound (E) is used, and is particularly remarkable when an additive for hydraulic compositions containing both the organic sulfur compound (D) and the carbonate ester compound (E) is used.

[0063] Table 1: Composition and evaluation results of additives for hydraulic compositions [Table 1]

[0064] Table 2: Composition and evaluation results of additives for hydraulic compositions [Table 2] [Industrial Applicability]

[0065] The present invention is applicable to hydraulic compositions such as concrete.

Claims

1. tertiary alkanolamines (A), a dihydric to tetrahydric polyhydric alcohol (B) that does not contain either an amino group or a carboxy group; and a primary alkanolamine (C).

2. The additive for hydraulic compositions according to claim 1, wherein the tertiary alkanolamines (A) include at least one compound selected from the group consisting of triisopropanolamine and N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine.

3. The additive for hydraulic compositions according to claim 1, wherein the polyhydric alcohol (B) contains at least one compound selected from the group consisting of diethylene glycol and glycerin.

4. the primary alkanolamines (C) include a compound represented by formula (1), 【Chemistry 1】 In formula (1), R is a group selected from the group consisting of a hydrogen atom, a methyl group, an ethyl group, a propyl group, a hydroxymethyl group, a 1-hydroxyethyl group, and a 2-hydroxyethyl group; The additive for hydraulic compositions according to claim 1 , wherein one of X and Y is an amino group and the other is a hydroxy group.

5. relative to the total content of the tertiary alkanolamines (A), the polyhydric alcohol (B), and the primary alkanolamines (C), the content of the tertiary alkanolamines (A) is 30% by mass or more and 70% by mass or less, the content of the polyhydric alcohol (B) is 20% by mass or more and 60% by mass or less, The additive for hydraulic compositions according to claim 1, wherein the content of the primary alkanolamines (C) is 10% by mass or more and 40% by mass or less.

6. an organic sulfur compound (D) containing at least one compound selected from the group consisting of dialkyl sulfones and dialkyl sulfoxides; and The additive for hydraulic compositions according to claim 1, further comprising at least one component selected from the group consisting of carbonate ester compounds (E).

7. The additive for hydraulic compositions according to claim 6, comprising the organic sulfur compound (D) and the carbonate ester compound (E).

8. The additive for hydraulic compositions according to claim 6, wherein the organic sulfur compound (D) contains dimethyl sulfone.

9. The additive for hydraulic compositions according to claim 6, wherein the carbonate ester compound (E) includes glycerol 1,2-carbonate.

10. relative to the total content of the tertiary alkanolamines (A), the polyhydric alcohol (B), the primary alkanolamines (C), the organic sulfur compound (D), and the carbonate ester compound (E), the content of the tertiary alkanolamines (A) is 20% by mass or more and 50% by mass or less, the content of the polyhydric alcohol (B) is 20% by mass or more and 50% by mass or less, the content of the primary alkanolamines (C) is 15% by mass or more and 40% by mass or less, The content of the organic sulfur compound (D) is 0% by mass or more and 20% by mass or less, The content of the carbonate ester compound (E) is 0% by mass or more and 20% by mass or less, and The additive for hydraulic compositions according to claim 6, wherein at least one of the content of the organic sulfur compound (D) and the content of the carbonate ester compound (E) is greater than 0 mass%.

11. A hydraulic composition comprising cement, water, a dispersant, and the additive for hydraulic compositions according to any one of claims 1 to 10.

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