JP7020668B2 - Additives for hydraulic composition and method for preparing hydraulic composition - Google Patents

Description

The present invention relates to an additive for a hydraulic composition, and more particularly to an additive for a hydraulic composition capable of increasing the strength of the initial age of a cured product obtained by curing the prepared hydraulic composition. ..

The hydraulic composition is obtained by kneading a hydraulic binder and a material such as water and then filling the mold, and after curing, the mold is demolded to obtain a cured product. Among them, concrete products are commercialized by kneading materials such as cement, water, aggregates, and dispersants, placing them in a mold, and hardening them. Improving the strength of the initial age leads to the ability to produce more concrete products using the same formwork. Therefore, it is required to shorten the time to reach the strength that can be removed from the mold after placing concrete. So far, various additives have been studied, and inorganic salts such as calcium chloride, nitrite and nitrate (for example, Non-Patent Document 1), glycerin, alkanolamine and the like are disclosed (for example, Patent Documents 1 and 2). ).

Japanese Unexamined Patent Publication No. 2009-256201 Japanese Unexamined Patent Publication No. 2011-236127

Fumiki Tomozawa et al., "Development and Latest Technology of Concrete Admixtures", CMC Publishing Co., Ltd., 1995

The use of calcium chloride is restricted due to the problem of corrosion when reinforced concrete is used, and a large amount of nitrite or nitrate may be added. Alkanolamine and glycerin can also improve the strength of the initial age, but further improvement of the strength of the initial age is required.

An object of the present invention is to improve the premature strength so that the strength required for demolding can be obtained in a shorter time. Specifically, it is to secure the demolding strength by curing at 20 ° C. for about 24 hours.

As a result of research to solve the above-mentioned problems, the present inventors have found that an additive for a water-hard composition containing a specific organic compound is correctly suitable. According to the present invention, the following additives for hydraulic composition and a method for preparing a hydraulic composition are provided.

[1] Compound A and / or a salt thereof represented by the following formula (1), and one or more compounds B selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol, and dipropylene glycol. An additive for a water-hard composition, which is contained.

（ただし、上記式（１）において、Ｘは、水素原子またはヒドロキシ基を示す。）

(However, in the above formula (1), X represents a hydrogen atom or a hydroxy group.)

(delete)

[ 2 ] The additive for a hydraulic composition according to [1 ], which further contains a dispersant for a hydraulic composition.

[ 3 ] The additive for a water-hard composition according to [ 2 ], wherein the dispersant for a water-hard composition is a polycarboxylic acid-based dispersant or an aromatic sulfonic acid-based compound.

[ 4 ] The additive for hydraulic composition according to any one of [1] to [ 3 ], and the compound A in the additive for hydraulic composition is the hydraulic binder 100 in the hydraulic composition. A method for preparing a hydraulic composition, which is added and contained in a ratio of 0.001 to 1.0 parts by mass with respect to parts by mass.

[ 5 ] The method for preparing a hydraulic composition according to [ 4 ], wherein the ratio of the compound A is 0.05 to 0.8 parts by mass with respect to 100 parts by mass of the hydraulic binder.

The additive for a hydraulic composition of the present invention can increase the strength of the initial material age of a cured product obtained by curing the prepared hydraulic composition. Therefore, according to the additive for hydraulic composition of the present invention, the early strength can be improved so that the strength required for demolding can be obtained in a shorter time.

Hereinafter, embodiments of the present invention will be described. However, the present invention is not limited to the following embodiments. Therefore, it should be understood that the following embodiments can be appropriately modified, improved, or the like based on the ordinary knowledge of those skilled in the art without departing from the spirit of the present invention. In the following examples and the like, unless otherwise specified,% means mass% and parts mean parts by mass.

The additive for a hydraulic composition according to the embodiment of the present invention is an additive for a hydraulic composition containing the compound A represented by the following formula (1) and / or a salt thereof. The additive for a hydraulic composition of the present embodiment can increase the strength of the initial material age of a cured product obtained by curing the prepared hydraulic composition. Therefore, according to the additive for hydraulic composition of the present embodiment, it is possible to improve the early strength so that the strength required for demolding can be obtained in a shorter time. For example, at 20 ° C., it is possible to secure the demolding strength by curing for about 24 hours.

（ただし、上記式（１）において、Ｘは、水素原子またはヒドロキシ基を示す。）

(However, in the above formula (1), X represents a hydrogen atom or a hydroxy group.)

The compound A represented by the above formula (1) to be used as the additive for the water-hardening composition of the present embodiment (hereinafter, also simply referred to as the additive of the present embodiment) is trishydroxymethylaminomethane and / or 2-amino. -2-Methyl-1,3-propanediol can be mentioned. Examples of the salt of the compound A include those in which the amino group in the formula (1) is a salt due to an acid or the like.

There is no particular limitation on the amount to be added when preparing the hydraulic composition using the additive of the present embodiment. For example, in the additive of the present embodiment, the compound A in the additive is preferably 0.001 to 1.0 part by mass, more preferably 0.001 to 1.0 part by mass, based on 100 parts by mass of the water-hard binder in the water-hard composition. Is added in a proportion of 0.005 to 0.8 parts by mass, more preferably 0.05 to 0.8 parts by mass. If it is too small, the desired effect cannot be obtained, and if it is too large, it costs too much.

The additive of this embodiment contains the following compound B. By containing the compound B, the desired effect can be realized to a higher degree.

Examples of compound B include ethylene glycol, propylene glycol, diethylene glycol, and dipropylene glycol, and examples thereof include triethanolamine, diethanolamine, triisopropanolamine, and diisopropanolamine. Compound B may be used alone or in combination of two or more.

When the additive of the present embodiment further contains the above-mentioned compound B, the content of the compound B is not particularly limited. For example, when preparing a water-hardening composition using the additive of the present embodiment, the compound B in the additive is preferably 0 with respect to 100 parts by mass of the water-hardening binder in the water-hardening composition. It is contained in the additive of the present embodiment so as to be 001 to 1.0 part by mass, more preferably 0.005 to 0.5 part by mass, and further preferably 0.005 to 0.2 part by mass. Is preferable.

The additive of the present embodiment may further contain a dispersant for a hydraulic composition. The dispersant for the water-hard composition is not particularly limited, but for example, (1) aromatic sulfonic acid-based dispersions such as (1) naphthalene-based dispersants, melamine-based dispersants, phenol-based dispersants, and lignin-based dispersants. Examples thereof include dispersants such as (2) polycarboxylic acid-based dispersants and (3) phosphate ester-based dispersants. Among them, those selected from the group consisting of naphthalene-based dispersants and polycarboxylic acid-based dispersants are preferable from the viewpoint of ensuring early toughness.

(A) Examples of the naphthalene-based dispersant include naphthalene sulfonic acid formaldehyde condensate (Mighty 150 (trade name) manufactured by Kao Corporation, Pole Fine 510-AN (trade name) manufactured by Takemoto Oil & Fats Co., Ltd.) and the like. .. (B) Examples of the melamine-based dispersant include melamine sulfonic acid formaldehyde condensate (Paul Fein MF (trade name) manufactured by Takemoto Oil & Fat Co., Ltd., Accelerate 100 (trade name) manufactured by Nissan Chemical Industry Co., Ltd.) and the like. Will be. (C) Examples of the phenolic dispersant include a phenol sulfonic acid formaldehyde condensate (compound described in JP-A-46-10419), a phenol phosphate formaldehyde condensate (compound described in JP-A-2012-504695), and the like. Can be mentioned. (D) Examples of the lignin-based dispersant include lignin sulfonate (Sun Extract (trade name), Vanillex (trade name), Pearl Rex (trade name), etc. manufactured by Nippon Paper Chemicals Co., Ltd.).

Examples of the polycarboxylic acid-based dispersant include a copolymer of a monoester of polyalkylene glycol and (meth) acrylic acid and a carboxylic acid such as (meth) acrylic acid; unsaturated alcohol having polyalkylene glycol and (meth) acrylic. Copolymer with carboxylic acid such as acid (for example, JP-A-2007-119337); Copolymer of unsaturated alcohol having polyalkylene glycol and dicarboxylic acid such as maleic acid; Commercially available polycarboxylic acid-based dispersion A dispersant containing an agent or the like can be used. In addition, (meth) acrylic acid means acrylic acid or methacrylic acid.

As a typical example of a polycarboxylic acid-based dispersant, a copolymer obtained by polymerizing a monomer (M-1) represented by the following formula (2) and a monomer (M-2) having a carboxylic acid. The coalescence can be mentioned.

In equation (2)
R ¹ represents an alkenyl group having 2 to 5 carbon atoms and an unsaturated acyl group having 3 or 4 carbon atoms.
^R2 represents a hydrogen atom, an alkyl group having 1 to 22 carbon atoms or an aliphatic acyl group having 1 to 22 carbon atoms.
X represents a (poly) oxyalkylene group having an average addition mole number of 1 to 300, which is composed of one or more of the oxyalkylene groups having 2 to 4 carbon atoms.

Examples of the alkenyl group having 2 to 5 carbon atoms of ^R1 in the formula (2) include a vinyl group, an allyl group, a methallyl group, a 3-butenyl group, a 2-methyl-1-butenyl group, and a 3-methyl-1-butenyl group. Examples thereof include a group, a 2-methyl-3-butenyl group, a 3-methyl-3-butenyl group and the like. Examples of the unsaturated acyl group having 3 or 4 carbon atoms of R ¹ include an acryloyl group and a methacryloyl group. Among these, an allyl group, a methallyl group, a 3-methyl-1-butenyl group, an acryloyl group, and a methacryloyl group are preferable. One or two or more structural units represented by these equations (2) may be used.

Examples of R ² in the formula (2) include 1) a hydrogen atom, 2) an alkyl group having 1 to 22 carbon atoms, and 3) an aliphatic acyl group having 1 to 22 carbon atoms.

Examples of X in the formula (2) include a polyoxyalkylene group composed of 1 to 300 (poly) oxyalkylene units. Of these, a (poly) oxyalkylene group composed of 1 to 160 oxyethylene units and / or oxypropylene units is preferable.

The monomer (M-2) having a carboxylic acid (hereinafter, also simply referred to as “monomer (M-2)”) constituting the (co) polymer is (meth) acrylic acid. , Crotonic acid, dicarboxylic acid, maleic acid, itaconic acid, fumaric acid, monosuccinic acid (2- (meth) acryloyloxyethyl) and the like and salts thereof. Among them, as the monomer (M-2), (meth) acrylic acid, maleic acid, (meth) acrylic acid salt, and maleate salt are preferable.

The salt of the monomer (M-2) having a carboxylic acid is not particularly limited, but for example, an alkali metal salt such as a sodium salt or a potassium salt, or an alkaline earth metal salt such as a calcium salt or a magnesium salt. , Ammonium salt, amine salt such as diethanolamine salt and triethanolamine salt and the like.

The dispersant for a hydraulic composition used as an additive of the present embodiment is not limited to the (co) polymer described above. For example, when producing a (co) polymer to be used as a dispersant for a hydraulic composition, any other suitable monomer may be used. For example, styrene, acrylamide, (meth) allylsulfonic acid and salts thereof may be mentioned.

The additive of this embodiment is used when preparing a hydraulic composition. For example, it is used when preparing a concrete composition using cement, water, fine aggregate, coarse aggregate, AE agent and the like.

The additive of the present embodiment is added as a part of the kneading water when preparing the hydraulic composition. The addition ratio is preferably 0.001 to 1.0% by mass, and more preferably 0.01 to 0.5% by mass with respect to the hydraulic binder.

Examples of the hydraulic binder include cement, blast furnace slag fine powder, fly ash, gypsum, hemihydrate gypsum, and anhydrous gypsum. Of these, cement is preferable. As the cement, various Portland cements such as ordinary Portland cement, early-strength Portland cement, and moderate heat Portland cement, as well as various mixed cements such as blast furnace cement, fly ash cement, and silica fume cement can be used.

Further, as the fine aggregate, known river sand, mountain sand, sea sand, crushed sand, slag sand and the like can be used. Further, as the coarse aggregate, known river gravel, crushed stone, lightweight aggregate and the like can be used.

Further, other cement dispersants used for preparing the concrete composition may be used at the same time. Examples of the air amount adjusting agent include rosin soap, alkyl aromatic sulfonates, aliphatic alkyl (ether) sulfates, and alkyl phosphate esters. Various known antifoaming agents can be used depending on the situation.

When using the additive of the present embodiment, other agents can be used in combination as long as the present invention is not impaired. Examples of the other agent used in combination with the additive of the present embodiment include other coagulation promoters, coagulation retarders, rust preventives, waterproofing agents and the like. Further, the method of using the additive of the present embodiment may be either a method of adding the additive together with the kneading water at the time of preparing the concrete composition, a method of adding the additive to the concrete composition immediately after kneading, or the like.

In the additive of the present embodiment, compound A and other components may be mixed in advance to prepare a one-component hydraulic composition additive.

Next, an embodiment of the method for preparing a hydraulic composition of the present invention will be described. The method for preparing a hydraulic composition of the present embodiment is a method for preparing a hydraulic composition using the additive for hydraulic composition (additive for hydraulic composition of the present invention) described so far. In the method for preparing the hydraulic composition of the present embodiment, the additive for the hydraulic composition of the present invention is used, and the compound A in the additive for the hydraulic composition is the hydraulic binder 100 in the hydraulic composition. This is a preparation method in which the mixture is added so as to have a ratio of 0.001 to 1.0 parts by mass with respect to parts by mass.

According to the method for preparing a hydraulic composition of the present embodiment, it is possible to improve the premature strength so that the strength required for demolding can be obtained in a shorter time. For example, at 20 ° C., it is possible to secure the demolding strength by curing for about 24 hours.

In the method for preparing the water-hard composition of the present embodiment, the ratio of compound A in the additive for the water-hard composition is 0.05 to 0.8 parts by mass with respect to 100 parts by mass of the water-hard binder. Is preferable.

Hereinafter, examples and the like will be given in order to make the configuration and effect of the present invention more specific, but the present invention is not limited to the examples. In the following examples and the like, unless otherwise specified,% means mass% and parts mean parts by mass.

Preparation of Additives for Hydraulic Composition ( Reference Example 1, Examples 2 to 7):
As compound A, trishydroxymethylaminomethane (manufactured by ANGUS) and 2-amino-2-methyl-1,3-propanediol (Tokyo Kasei reagent) were prepared, and as compound B, AD-1 to AD shown below were prepared. -5 was prepared. Compound A and compound B were mixed in advance at the ratios shown in Table 1 and appropriately diluted with ion-exchanged water. In this way, the additives for the hydraulic composition of Reference Example 1 and Examples 2 to 7 were prepared. The additives for the hydraulic composition of Reference Example 1 and Examples 2 to 7 were designated as EX-1 to EX-7 in Table 1.

In Table 1, the following terms have the following meanings.
a-1: Trishydroxymethylaminomethane (manufactured by ANGUS).
a-2: 2-Amino-2-methyl-1,3-propanediol (Tokyo Kasei Reagent).
AD-1: Diethylene glycol (Kishida chemical reagent).
AD-2: Ethylene glycol (Kishida chemical reagent).
AD-3: Triisopropanolamine (Wako Pure Chemical Industries, Ltd.).
AD-4: Triethanolamine (Kishida Chemical Reagent).
AD-5: Glycerin (Wako Pure Chemical Industries, Ltd.).

-Preparation of additives for hydraulic composition (Comparative Examples 1 and 2)
Compound B shown in Table 1 was appropriately diluted with ion-exchanged water to prepare additives for hydraulic compositions of Comparative Examples 1 and 2. The additives for the hydraulic composition of Comparative Examples 1 and 2 were designated as R-1 and R-2 in Table 1.

The mass average molecular weights of the following copolymers (PC-1) to (PC-3) were measured by gel permeation chromatography. The following copolymers (PC-1) to (PC-3) were used as a dispersant for a hydraulic composition as an additive for a hydraulic composition in each Example and Reference Example .
<Measurement conditions>
Equipment: Shodex GPC-101 (manufactured by Showa Denko).
Column: OHpak SB-G + SB-806M HQ + SB-806M HQ (manufactured by Showa Denko).
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 a sample concentration of 0.5% by weight.
Standard material: polyethylene oxide, polyethylene glycol.

-Manufacturing of copolymer (PC-1):
First, as raw materials for producing the copolymer (PC-1), ion-exchanged water 165.5 g, α-methacryloyl-ω-methoxy-poly (n = 45) oxyethylene 133.4 g, methacrylic acid 22.2 g, 3 -1.6 g of mercaptopropionic acid was prepared. The prepared raw materials were placed in a reaction vessel equipped with a thermometer, a stirrer, a dropping funnel, and a nitrogen introduction tube (hereinafter, the same was used) and uniformly dissolved while stirring. Then, the atmosphere of the reaction system in which each of the above-mentioned components was dissolved was replaced with nitrogen, and the temperature of the reaction system was set to 65 ° C. in a water bath. Next, 27.3 g of 1.0% hydrogen peroxide solution was added, and then the temperature was maintained at 65 ° C. for 6 hours to complete the polymerization reaction. Then, a 30% aqueous sodium hydroxide solution was added to adjust the pH to 6, and the concentration was adjusted to 40% with ion-exchanged water to obtain a reaction mixture. The mass average molecular weight of the obtained reaction mixture was measured and found to be 35,000. This reaction mixture was designated as a copolymer (PC-1).

-Manufacturing of copolymer (PC-2):
41.4 g of ion-exchanged water was charged in a reaction vessel equipped with a thermometer, a stirrer, a dropping funnel, and a nitrogen introduction tube, the atmosphere was replaced with nitrogen while stirring, and the temperature of the reaction system was set to 70 ° C. in a warm water bath. Α-methacryloyl-ω-methoxy-poly (n = 130) oxyethylene 188.0 g, methacrylic acid 12.0 g, sodium methacrylic sulfonate 2.0 g, 3-mercaptopropionic acid 4.0 g in 188.0 g of ion-exchanged water The aqueous solution in which the solution was dissolved was added dropwise over 3 hours. At the same time, an aqueous solution prepared by dissolving 3.0 g of ammonium persulfate in 26.0 g of ion-exchanged water was added dropwise over 4 hours, and then the temperature was maintained at 70 ° C. for 1 hour to complete the polymerization reaction. Then, a 30% aqueous sodium hydroxide solution was added to adjust the pH to 6, and the concentration was adjusted to 40% with ion-exchanged water to obtain a reaction mixture. The mass average molecular weight of the obtained reaction mixture was measured and found to be 45,000. This reaction mixture was designated as a copolymer (PC-2).

-Manufacturing of copolymer (PC-3):
117.0 g of ion-exchanged water and 98.2 g of α- (3-methyl-3-butenyl) -ω-hydroxy-poly (n = 53) oxyethylene were provided with a thermometer, agitator, a dropping funnel, and a nitrogen introduction tube. It was charged into a reaction vessel and dissolved uniformly with stirring. Then, the atmosphere of the dissolved reaction system was replaced with nitrogen, and the temperature of the reaction system was adjusted to 70 ° C. in a warm water bath. Next, 7.9 g of 3.5% hydrogen peroxide solution was added dropwise over 3 hours. At the same time, an aqueous solution prepared by dissolving 9.5 g of acrylic acid in 47.2 g of ion-exchanged water was added dropwise over 3 hours. Further, at the same time, an aqueous solution prepared by dissolving 0.6 g of L-ascorbic acid and 0.6 g of 3-mercaptopropionic acid in 5.0 g of ion-exchanged water was added dropwise over 4 hours. Then, the temperature was maintained at 70 ° C. for 2 hours to complete the polymerization reaction. Then, a 30% aqueous sodium hydroxide solution was added to adjust the pH to 6, and the concentration was adjusted to 40% with ion-exchanged water to obtain a reaction mixture. The mass average molecular weight of the obtained reaction mixture was measured and found to be 46000. This reaction mixture was designated as a copolymer (PC-3).

Preparation of hydraulic composition ( Reference Examples 8, 13, 15, 16, Examples 9 to 12, 14, 17 and Comparative Examples 3 to 5):
The hydraulic composition was prepared by the following method. 55L forced twin-screw mixer with ordinary Portland cement (Pacific cement, Ube-Mitsubishi cement, Sumitomo Osaka Cement, 3 brands equal volume mixture, specific gravity = 3.16), fine aggregate (Oigawa water-based sand, specific gravity = 2) .57) and coarse aggregate (crushed stone from Okazaki, specific gravity = 2.66) were sequentially added at the ratios shown in Table 2 and kneaded for 10 seconds. After that, add an additive for hydraulic composition and an antifoaming agent (AFK-2 (trade name) manufactured by Takemoto Oil & Fat Co., Ltd.) so that the target slump is 18 ± 2.5 cm and the air volume is 2.0% or less. The mixture was added with kneading water and kneaded for 90 seconds to prepare a hydraulic composition. The amount (addition rate) of the additive for the hydraulic composition was as shown in Table 3. The defoaming agent was 0.002% of the cement.

-Slump: The hydraulic composition immediately after kneading was measured according to JIS-A1150.
-Amount of air: The concrete composition immediately after kneading was measured according to JIS-A1128.
-Compressive strength: Based on JIS-A1132, concrete was filled into three cylindrical steel formwork (bottom diameter: 100 mm, height 200 mm) by a two-layer packing method. Then, it was cured in the air (20 ° C.) in a room at 20 ° C. to harden the concrete. Twenty-four hours after the preparation of the concrete, the cured specimen was removed from the mold to obtain a specimen. The 24-hour strength of the specimen was measured based on JIS-A1108, and the average value of three specimens was obtained. Further, three other specimens were prepared by the same method as above, demolded from the specimens in the same manner, and then cured in water at 20 ° C. for 14 days, and the 14-day strength of the specimens was adjusted to JIS-A1108. The average value of 3 specimens was calculated based on the above. The results are shown in Table 3.

In Table 3, the following terms have the following meanings. The description of the terms that overlap with those shown in Table 1 will be omitted.
Addition rate: For the dispersant for hydraulic composition (“dispersant” in Table 3), the ratio (mass%) of the mass to the cement in the actual state is shown. For additives, the ratio of mass to cement in solid content (% by mass) is shown.
Dispersant: Dispersants for hydraulic compositions shown in the “Type” column of Table 3 are shown.
Additives: Additives for hydraulic compositions shown in the "Type" column of Table 3 are shown.
NFS: Naphthalene sulfonic acid formaldehyde condensate (Paul Fein 510AN (trade name) manufactured by Takemoto Oil & Fat Co., Ltd.).

(result)
In Reference Examples 8, 13, 15, 16 and Examples 9 to 12, 14, and 17, by using the additive containing compound A, the intensity was 24 hours and 14 days as compared with Comparative Examples 3 to 5. It was confirmed that all of them showed high values.

The additive for a hydraulic composition of the present invention can be used as an additive when preparing a hydraulic composition.

Claims (5)

It contains compound A represented by the following formula (1) and / or a salt thereof , and one or more compounds B selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol, and dipropylene glycol. An additive for water-hardening compositions.

(However, in the above formula (1), X represents a hydrogen atom or a hydroxy group.) The additive for a hydraulic composition according to claim 1 , further comprising a dispersant for a hydraulic composition. The additive for a water-hard composition according to claim 2 , wherein the dispersant for a water-hard composition is a polycarboxylic acid-based dispersant or an aromatic sulfonic acid-based compound. The additive for a hydraulic composition according to any one of claims 1 to 3 , wherein the compound A in the additive for a hydraulic composition is 100 parts by mass of a hydraulic binder in the hydraulic composition. A method for preparing a hydraulic composition, which is added so as to have a ratio of 0.001 to 1.0 part by mass with respect to the amount. The method for preparing a hydraulic composition according to claim 4 , wherein the ratio of the compound A is 0.05 to 0.8 parts by mass with respect to 100 parts by mass of the hydraulic binder.