JPH11157898A - Additive for hydraulic composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an additive for a hydraulic compsn. which shows excellent fluidity and separation resistance, good self-filling property, excellent initial strength and resistance against changes in the water amt. on the aggregate surface. SOLUTION: This additive contains a water-soluble polymer having <10% adsorptivity of adsorption characteristics to a cement, polysaccharide derivs. and a high-performance dewatering agent. The polysaccharide derivs. consist of polysaccharides or their alkylated or hydroxyalkylated derivs. in which hydrophobic substituents (A) having 8-40C hydrocarbon chains as a partial structure and ionic hydrophilic substituents (B) having one or more groups selected from sulfonic acid groups, carboxyl groups, phosphoric acid groups, sulfate groups or salts of these as a partial structure are substituted for hydrogen atoms of a part or whole hydroxyl groups.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an additive for a hydraulic composition having high fluidity and not requiring compaction, a hydraulic composition containing the additive, and a cured composition. More specifically, the present invention enhances the viscosity and fluidity of concrete, mortar and cement paste used as civil engineering / building materials and secondary product materials, and aggregates,
The present invention relates to an additive for a hydraulic composition capable of giving properties excellent in cement and water material separation resistance. A hydraulic composition using such an additive does not require compaction work by vibration of a vibrator or the like, and can provide physical properties excellent in curing properties at the time of casting.

[0002]

2. Description of the Related Art Hydraulic compositions represented by concrete, mortar, etc. are mainly used in civil engineering and construction fields.
Widely used for various applications.

[0003] In recent years, a so-called high fluidity hydraulic composition in which the fluidity of a hydraulic composition before curing is increased as compared with a general hydraulic composition has been actively developed. A typical example is high fluidity concrete. This has high fluidity compared to conventional concrete, that is, physical properties close to Newtonian fluidity, high viscosity and excellent separation resistance of material (hereinafter sometimes abbreviated as separation resistance),
It is a concrete that can be naturally filled into details without requiring compaction work or the like by vibration of a vibrator or the like, that is, self-filling concrete. Conventionally, in such high-flowable concrete, a high-performance water reducing agent has been used to increase the fluidity of the concrete, and a thickener, particularly a cellulose derivative such as methylcellulose or hydroxyethylcellulose, has been used as a method of increasing the separation resistance. ing.

[0004]

However, high fluidity hydraulic compositions have not yet reached a satisfactory practical stage. That is, as a simple example, taking concrete again as an example, using a thickener such as methylcellulose or hydroxyethylcellulose, a high-performance water reducing agent is added, and sufficient separation resistance is given to concrete having low viscosity. In order to provide such a thickener, it is necessary to add a large amount of these thickeners, resulting in an increase in cost and a problem of suppressing the hydration reaction of hydraulic powder such as cement, that is, causing a setting delay. Further, in an actual concrete plant, aggregates such as sand and gravel used for concrete are in a state where the surface water amount of the aggregates is constantly changing depending on the storage method and storage time. If the surface water amount of the aggregate is large, the fluidity of the high-fluidity concrete becomes too large, causing material separation. On the other hand, when the amount of surface water is small, the fluidity is lowered and sufficient self-filling property cannot be obtained. Therefore, it is very difficult to produce highly fluid concrete having stable fluidity, and there is a problem in quality control at present. Therefore, although it is clear that the high fluidity hydraulic composition has excellent advantages, it is still difficult to apply it to construction and civil engineering, especially to secondary products. Under such circumstances, excellent fluidity and separation resistance, that is, excellent self-filling properties can be imparted, excellent initial strength development, and high resistance to surface water volume fluctuation, that is, easy quality control. Development of an additive for a hydraulic composition is desired. An object of the present invention is to meet such a demand.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, a water-soluble polymer having an adsorption property to cement of less than 10% is contained in concrete. It has been found that controlling the viscosity of water has an effect of mitigating a change in the fluidity of a hydraulic composition such as highly fluidized concrete with respect to the variation in the surface water amount of the aggregate. On the other hand, a polysaccharide derivative obtained by substituting a hydroxyl group of a polysaccharide or a derivative thereof with a hydrophobic group such as a long-chain alkyl glyceryl ether group and an ionic hydrophilic group such as a sulfonic acid group is extremely small even under strong ionic strength. It exhibits a large thickening effect and can impart excellent separation resistance to the hydraulic composition while avoiding setting delay. Therefore, as a result of further study, by using the above water-soluble polymer as a thickening agent and a high-performance water reducing agent together with a polysaccharide derivative, quality control of fluidity becomes easy, and fluidity and separation resistance, and Found that the suppression of the hydration reaction of the hydraulic powder can be minimized, so that a hydraulic composition having excellent initial strength development can be obtained. The present invention has been completed based on these findings.

That is, the present invention relates to a water-soluble polymer (hereinafter sometimes referred to as a "non-adsorbing thickener") having an adsorption property of less than 10% for cement (a-1), a polysaccharide or A hydrogen atom of a part or all of the hydroxyl groups of the alkylated or hydroxyalkylated derivative is a hydrophobic substituent (A) having a hydrocarbon chain having 8 to 40 carbon atoms as a partial structure, and a sulfonic acid group, a carboxyl group, 1 selected from the group consisting of phosphate groups, sulfate groups and salts thereof
For a hydraulic composition containing a polysaccharide derivative (a-2) substituted with an ionic hydrophilic substituent (B) containing at least one kind of group as a partial structure, and a high-performance water reducing agent (b) It is an additive. Further, the present invention also provides a hydraulic composition containing a hydraulic powder and, if necessary, an aggregate, and a cured composition obtained therefrom.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The non-adsorbing type thickener (a-1) used in the hydraulic composition of the present invention has an adsorbing property to cement of less than 10%, and has an adverse effect on the fluidity of concrete. Considering the effect of the above, those having an adsorption rate of 5% or less are preferable.

The non-adsorbing type thickener (a-1) used in the hydraulic composition of the present invention may be any of those exhibiting the above-mentioned properties, but a preferred example is 6 to 30 in the molecule.
Monohydric alcohols with 6 carbon atoms, 6-30 in the molecule
Monovalent mercaptans having 6 carbon atoms in the molecule
Alkyl phenols having 30 carbon atoms, amines having 6 to 30 carbon atoms in the molecule or 6 to 30 carbon atoms in the molecule
And polyalkylene oxide derivatives obtained by adding 10 to 1000 moles of an alkylene oxide to a carboxylic acid having two carbon atoms.

A monohydric alcohol having 6 to 30 carbon atoms in the molecule, a monohydric mercaptan having 6 to 30 carbon atoms in the molecule, an alkylphenol having 6 to 30 carbon atoms in the molecule, a molecule Representative examples of amines having 6 to 30 carbon atoms in the molecule or carboxylic acids having 6 to 30 carbon atoms in the molecule include dodecyl alcohol, tridecyl alcohol, hexadecyl alcohol, 2-hexyldecyl Monohydric aliphatic alcohols such as alcohol and octadecyl alcohol; alicyclic monohydric alcohols such as abiethyl alcohol; monovalent aliphatic mercaptans such as dodecyl mercaptan and stearyl mercaptan; octylphenol, nonylphenol, dodecylphenol and dioctylphenol Alkyl phenols such as dodecyla Monovalent aliphatic amines such as min, nonylamine and stearylamine; monovalent fatty acids such as lauric acid (dodecanoic acid) and stearic acid; and one or a mixture of two or more of these. Can be used.

The alkylene oxide includes ethylene oxide, propylene oxide and butylene oxide. When two or more of these are used as the alkylene oxide, the addition molar ratio is preferably at least 80 mol% of ethylene oxide. Further, when the average number of added moles is about 100 to 500 moles, more preferable performance can be obtained.

The amount of the non-adsorption type thickener (a-1) is based on the amount of the hydraulic powder required for producing the hydraulic composition.
0.05-3.0% by weight of active ingredient, preferably 0.1-1.0% by weight
Is appropriate.

In the present invention, the non-adsorption type thickener (a-
By using 1) and the polysaccharide derivative (a-2) in combination, a hydraulic composition having good separation resistance and self-filling property can be obtained with a smaller amount of addition. The polysaccharide derivative (a-2) used as the thickener of the present invention is a polysaccharide or an alkylated or hydroxyalkylated derivative thereof, wherein a part or all of the hydrogen atoms of the hydroxyl groups have a hydrophobic substituent (A) and It is substituted by an ionic hydrophilic substituent (B). The hydrophobic substituent (A) has, as a partial structure, a hydrocarbon chain having 8 to 40 carbon atoms, which is more specifically 8 to 40 carbon atoms, preferably 12 to 36, more preferably 16 to 36 carbon atoms. An alkyl or alkenyl glyceryl ether group having 24 linear or branched alkyl or alkenyl groups, or a linear or branched chain having the same carbon number which may be substituted with an hydroxyl group or an oxycarbonyl group may be inserted. Examples include a branched alkyl group, alkenyl group, and acyl group. From the viewpoint of ease of production and other viewpoints, an alkyl glyceryl ether group, a long-chain alkyl group, and a 2-hydroxy long-chain alkyl group are preferable, and an alkyl glyceryl ether group is particularly preferable.
More specifically, as the alkyl glyceryl ether group,
2-hydroxy-3-alkoxypropyl group, 2-alkoxy-
1- (hydroxymethyl) ethyl group, 2-hydroxy-3-alkenyloxypropyl group, 2-alkenyloxy-1-
(Hydroxymethyl) ethyl group. These hydrophobic substituents (A) may be substituted with a hydrogen atom of a hydroxyl group of a hydroxyethyl group or a hydroxypropyl group bonded to a polysaccharide molecule.

The ionic hydrophilic substituent (B) is a substituent containing, as a partial structure, at least one group selected from the group consisting of a sulfonic acid group, a carboxyl group, a phosphate group, and a sulfate group. May form a salt. Specifically, a sulfoalkyl group having 1 to 5 carbon atoms which may be substituted by a hydroxyl group or a salt thereof, a carboxyalkyl group or a salt thereof, an alkyl phosphate group or a salt thereof, a sulfate ester alkyl group or a salt thereof, and the like Is mentioned. Preferably, it is a sulfoalkyl group having 1 to 5 carbon atoms which may be substituted by a hydroxyl group. More specifically, a 2-sulfoethyl group, a 3-sulfopropyl group, a 3-sulfoethyl group
2-hydroxypropyl group, 2-sulfo-1- (hydroxymethyl) ethyl group and the like, all or a part of which are alkali metals such as Na and K, alkaline earth metals such as Ca and Mg, amines Or a salt with an organic cation group such as a salt, an ammonium ion, or the like.

These polysaccharide derivatives according to the present invention have a hydrophobic substituent (A) from the viewpoint of solubility in kneading water and viscosity increase.
Is from 0.0001 to 1 per unit of the constituent monosaccharide residue.
And 0.0005 to 0.01 is more preferable. The degree of substitution by the ionic polar substituent (b) is 0.001 to 2 per unit of the constituent monosaccharide residue, and is more preferably 0.01 to 1. Particularly preferred substitution degree is 0.0007 to 0.00 for the hydrophobic substituent (A).
5, and the ionic hydrophilic substituent (B) is 0.02 to 0.15.

In the present invention, the polysaccharides include cellulose, starch, rhizome polysaccharide, sap polysaccharide, seed polysaccharide,
Seaweed polysaccharide, animal polysaccharide, and microbial polysaccharide. Examples of the ionic groups substituted include anionic group-substituted products such as carboxymethyl cellulose and cellulose sulfate. Examples of the alkylated or hydroxyalkylated derivative of the polysaccharide include hydroxyethylated, hydroxypropylated, and methylated polysaccharides.
Examples include ethylated products, and among them, cellulose such as cellulose, hydroxyethyl cellulose, methyl cellulose, ethyl cellulose, and hydroxypropyl cellulose, and derivatives thereof are preferable. When the substituent is an alkyleneoxy group, the degree of substitution, that is, the number of moles added per constituent monosaccharide residue is preferably 0.1 to 10, particularly preferably 0.5 to 5. Further, the weight average molecular weight of these polysaccharides or derivatives thereof is 10,000 to 10,000,000, and particularly preferably 100,000 to 5,000,000.

The substituted polysaccharide derivative of the present invention is characterized in that the hydrogen atom of the hydroxyl group of the polysaccharide or its alkylated or hydroxyalkylated derivative is partially hydrophobicized (introduction of the hydrophobic substituent (A)) or hydrophilized ( After the introduction of the ionic hydrophilic substituent (B)), part or all of the remaining hydroxyl groups can be hydrophilized or hydrophobized, respectively, or by performing hydrophobization and hydrophilization simultaneously.

The introduction of a substituent can be carried out, for example, as follows. That is, a polysaccharide or a derivative thereof is converted into an alkyl or alkenyl glycidyl ether having 8 to 40 carbon atoms in the presence of an alkali,
A hydrophobic substituent by reacting with an epoxide, halide, halohydrin, acyl halide, or an ester or carboxylic anhydride having an acyl group having 8 to 40 carbon atoms of a linear or branched saturated or unsaturated alkyl having from 40 to 40 (A) is introduced, and vinyl sulfonic acid or a haloalkanesulfonic acid having 1 to 5 carbon atoms which may be substituted with a hydroxyl group in the presence of an alkali, a halocarboxylic acid, a halophosphate ester, a halosulfate ester or a salt thereof And the like. The method for producing such polysaccharide derivatives is described, for example, in EP 0781780.
-A2.

The amount of the polysaccharide derivative to be added in the present invention may be appropriately determined according to the desired degree of thickening. For example, the amount of the polysaccharide derivative is effective for the amount of hydraulic powder required for producing a hydraulic composition. The suitable amount is 0.0001 to 3% by weight, preferably 0.001 to 0.5% by weight, particularly preferably 0.01 to 0.1% by weight.

The non-adsorbing thickener (a-1) and the polysaccharide derivative (a-
The content ratio or addition ratio in the hydraulic composition of 2) is preferably (a-1) / (a-2) = 100/1 to 1/1 by weight ratio. More preferably, it is about 50/1 to 2/1.

The high-performance water reducing agent (b) used in the present invention, that is, the chemical admixture for concrete having a water reduction rate of 18% or more specified in JIS A 6204, includes any of naphthalene, melamine, phenol, urea and aniline. And a formaldehyde condensate of one or more compounds selected from the group of methylolated and sulfonated products. For example, a naphthalenesulfonic acid metal salt formaldehyde condensate [eg Kao Corporation Mighty 150], a melamine sulfonic acid metal salt formaldehyde condensate [eg Kao Corporation Mighty 150-V2], a phenolsulfonic acid formaldehyde compound (Patent No. No. 1097647), phenol / sulfanilic acid formaldehyde cocondensate (compounds described in JP-A-1-113419), and the like. Still other examples include ethylenically unsaturated monocarboxylic acids, alkylene oxide adducts or derivatives thereof, and ethylenically unsaturated dicarboxylic acids,
Polymers or copolymers obtained by polymerizing monomers containing one or more selected from the group consisting of alkylene oxide adducts and derivatives thereof (Japanese Patent Publication No. 2-7901; -75252, JP-B-2-8983, and the like).

Further, the high-performance water reducing agent used in the present invention includes a monomer represented by the following general formula (1) and a compound represented by the following general formulas (2) and (3). A water-soluble vinyl copolymer having an oxyalkylene group obtained by polymerizing a monomer containing one or more selected monomers is particularly preferably used (for example, Mighty 3000 manufactured by Kao Corporation). Such a high-performance water reducing agent is described in, for example, JP-A-7-223852.

[0022]

Embedded image

Wherein R ₁ , R ₂ : hydrogen atom or methyl group m ₁ : number of 0 to 2 AO: oxyalkylene group having 2 to 3 carbons n: number of 1 to 300 X: hydrogen atom or carbon Represents an alkyl group of Formulas 1 to 3. ]

[0024]

Embedded image

[Wherein, R ₃ , R ₄ , R ₅ : hydrogen atom, methyl group or (CH ₂ ) m ₂ COOM ₂ R ₆ : hydrogen atom or methyl group M ₁ , M ₂ , Y: hydrogen atom, alkali Metal, alkaline earth metal, ammonium, alkylammonium or substituted alkylammonium m ₂ : represents the number of 0 to 2; In the above-mentioned copolymer used as a preferred high-performance water reducing agent, the monomer represented by the general formula (1) includes methoxyethylene glycol, methoxypolyethylene glycol, ethoxypolyethylenepolypropylene glycol, propoxypolyethyleneglycol, and the like. Ethylene oxide and propylene to the esterified product of one-terminal alkyl-blocked polyalkylene glycol and the dehydrogenation (oxidation) reaction product of (meth) acrylic acid or fatty acid, and the dehydrogenation (oxidation) reaction product of (meth) acrylic acid or fatty acid An oxide adduct is used. As the repeating unit of the polyalkylene glycol monomer, any of ethylene oxide alone, propylene oxide alone, and random, block, or alternate addition of ethylene oxide and propylene oxide can be used. The addition mole number of the repeating unit of the polyalkylene glycol monomer is
When it is 10 to 200, further preferably 110 to 150, it is particularly preferable in terms of shortening of curing delay, high fluidity, high filling property, and high separation reducing property.

The compound represented by the above general formula (2) includes, as an unsaturated monocarboxylic acid monomer, acrylic acid,
Methacrylic acid or crotonic acid, maleic anhydride, maleic acid, itaconic anhydride, itaconic acid, citraconic anhydride, citraconic acid or fumaric acid as an unsaturated dicarboxylic acid-based monomer, and further an alkali metal salt or an alkaline earth metal thereof. Salts, ammonium salts, amine salts, substituted amine salts.

The compound represented by the above general formula (3) includes allyl sulfonic acid, methallyl sulfonic acid, or an alkali metal salt, an alkaline earth metal salt, an ammonium salt, an amine salt, a substituted amine salt thereof. Is mentioned.

The amount of the high-performance water reducing agent (b) in the present invention can be appropriately determined according to the desired fluidity, but is generally 0.1 to 5% by weight, preferably 0.1 to 5% by weight, based on the hydraulic powder. 0.5 to 3% by weight.

The additive for a hydraulic composition of the present invention containing the above-mentioned water-soluble polymer (a-1), polysaccharide derivative (a-2) and high-performance water reducing agent (b) is added. The hydraulic powder is a powder having physical properties to be hardened by a hydration reaction, and examples thereof include cement and gypsum. In addition, the hydraulic composition finally obtained by adding sand, sand and gravel as an aggregate to these powders is generally mortar,
It is called concrete.

The hydraulic powder used in the hydraulic composition of the present invention further includes fine powder having a specific surface area of 3,000 cm ² / g or more, blast furnace slag, fly ash, silica fume, stone powder and the like. One or more fine powders selected from the following may be used.

As described above, in these hydraulic compositions, those having high fluidity and physical properties excellent in separation resistance are called self-filling ones. This property is particularly important for concrete to which gravel or the like that is easy to separate is added. Concrete having such physical properties is called self-compacting concrete, and the present invention exerts its effects particularly on the self-compacting concrete among various hydraulic compositions.

When the hydraulic composition of the present invention is used as a high fluidity concrete, a slump flow value of 50 cm or more is required in a slump test specified in JIS A1101. Slump flow value to ensure sufficient filling
50-70 cm is preferred. If the slump flow value is less than 50 cm, sufficient filling properties cannot be secured. Slump flow value is 70cm
If the ratio exceeds the limit, the cement paste and the gravel are separated from each other, and clogging occurs between the reinforcing bars due to the gravel. As a result, sufficient filling properties cannot be obtained.

In the present invention, the water-soluble polymer (a-1), polysaccharide derivative (a-2) and high-performance water reducing agent (b) can be added to the hydraulic composition either in the form of an aqueous solution or a powder. The addition time may be before kneading the hydraulic composition, such as dry blending with a hydraulic powder, dissolution in kneading water, or the kneading period of the hydraulic composition, that is, hydraulic It can be added at the same time as or immediately after the water is injected into the powder and before the kneading of the hydraulic composition is completed. Furthermore, it is also possible to add it later to the hydraulic composition once kneaded. Either a method of adding the whole amount at a time or a method of adding several times at a time can be adopted.

A known dispersant can be used in combination with the additive for hydraulic composition of the present invention. For example, lignin sulfonic acid or a salt thereof, oxycarboxylic acid or a salt thereof,
And polyalkyl carboxylic anhydrides or salts thereof (for example, JP-B-63-5346, JP-A-62-83344,
JP-A-1-270550) and the like.

Also, other additives (materials) for hydraulic compositions,
For example, a sustained-release dispersant, aE water reducing agent, superplasticizer, retarder,
Fasteners, accelerators, foaming agents, foaming agents, defoamers, water retention agents, thickeners, self-leveling agents, waterproofing agents, rust inhibitors, coloring agents,
Fungicides, crack reducers, polymer emulsions, other surfactants, other water-soluble polymers, swelling agents (materials),
It is also possible to use one kind or two or more kinds such as glass fiber.

[0036]

As described above, according to the additive for hydraulic composition of the present invention, it is possible to ensure high fluidity, resistance to material separation of aggregates and the like, and strength, and to always maintain stable quality. The use of hydraulic compositions such as concrete and the method of construction are dramatically improved, and the ripple effect is particularly large in general buildings. Also, in the production of hydraulic composition products such as concrete products, productivity can be improved and rationalized because noise is eliminated during production and the initial cured physical properties are excellent.

[0037]

EXAMPLES The present invention will be described below with reference to production examples and examples, but the present invention is not limited to these examples. In the following examples, "EO" represents "ethylene oxide", "PO" represents propylene oxide, and the number of moles added represents the average number of moles added. Unless otherwise specified, “%” is “% by weight”.

Table 1 shows the non-adsorption type thickener (a-1) used.

[0039]

[Table 1]

Production Example 1 Trade name Calcol 86 (mixture of stearyl alcohol and cetanol: manufactured by Kao Corporation under the nitrogen atmosphere at 140 ° C. under the condition of ethylene oxide using an alkaline catalyst at 20 ° C.
0 mol was added. Production Example 2 According to Production Example 1, ethylene oxide and propylene oxide were randomly added to nonylphenol at a molar ratio of 10: 1 (200 moles of EO addition: 20 moles of PO addition). Production Example 3 The water-soluble polymer produced in Production Example 1 and polyethylene glycol (molecular weight 10,000) were mixed at a weight ratio of 8: 2. Production Example 4 According to Production Example 1, 320 mol of ethylene oxide was added to dodecyl mercaptan. Production Example 5 According to Production Example 1, lauric acid was replaced with ethylene oxide 26.
0 moles were added.

The method for measuring the adsorption rate of the above-mentioned water-soluble polymer (thickener) is as follows. [Method for Measuring Adsorption Characteristics of Water-Soluble Polymer (Thickener) on Cement] Using ordinary Portland cement (hereinafter abbreviated as cement), the weight ratio of water / cement is 100%.
Then, cement is added to a 0.5% by weight aqueous solution of a water-soluble polymer, and the mixture is manually stirred for 5 minutes and left to stand for 25 minutes. Then, the obtained cement paste is centrifuged at 3000 rpm for 15 minutes, and the amount of the water-soluble polymer in the separated supernatant is measured by organic carbon content analysis (TOC). The difference between the amount of the water-soluble polymer added first and the amount of the water-soluble polymer in the supernatant is determined, and the difference is determined as the amount of adsorption to the cement. The ratio of the amount of adsorption to the initial amount of addition is defined as the adsorption ratio.

Next, the polysaccharide derivative (a-2) used is shown in Table 2.
Shown in The “degree of substitution” in Table 2 indicates an average value of substituents per constituent monosaccharide residue.

[0043]

[Table 2]

Table 3 below shows the high-performance water reducing agent (b) used.

[0045]

[Table 3]

<< Evaluation as Hydraulic Composition >> Table 4 shows the mixing conditions of concrete.

[0047]

[Table 4]

(Materials used) Water (abbreviated symbol W): tap water Cement (C): ordinary Portland cement (specific gravity 3.1
6) Fine aggregate (S): Kinokawa river sand: Kimitsu land sand = 1: 1
(Specific gravity 2.57, coarse grain ratio 2.57) Coarse aggregate (G): Lime crushed stone from Kochi (specific gravity 2.72, coarse grain ratio 7.
03, maximum dimension 20 mm) For the hydraulic composition of Table 4, the high-performance water reducing agent shown in Table 3 was used in the amount shown in Table 5 below. The water-soluble polymer shown in Table 1 was used as a non-adsorption type thickener (a-1) as shown in Table 5, and the polysaccharide derivative (a-2) as a thickener was shown in Table 2. Admixtures 1-9 were used as shown in Table 5. Mixing of hydraulic composition is performed by using a 100-liter forced twin-screw mixer at 20 ° C, premixing a high-performance water reducing agent and a polysaccharide derivative, dissolving in water, and kneading 50-liter concrete for 2 minutes. Made by. Thereafter, five types of evaluation items of the following slump flow, separation resistance, self-filling property, daily strength, and surface water volume fluctuation resistance of the fine aggregate were measured.

<Evaluation Items> Slump flow Slump flow value according to JIS A 1101 (cm).

2. Separation resistance Evaluation was made by visual observation (visually). The evaluation criteria are as follows.

○: No separation of aggregate and no separation of water Δ: Some separation of separation of aggregate and water ×: Separation of aggregate and separation of water Self-filling property After mixing and mixing concrete, concrete was poured into a cylindrical formwork of φ10 cm, and after hardening and demolding, the filling state of the concrete surface was visually observed. The evaluation criteria are as follows.

◎: No voids were generated. ○: No voids of 3 mm or more were generated. Δ: Some voids of 3 mm or more were slightly generated. X: Many voids were generated of 3 mm or more. 4.1 day strength Compressive strength of JIS A 1108 The daily strength was measured by a test. The evaluation criteria are as follows.

A: 80-100 kgf / cm ² ○: 50-80 kgf / cm ² Δ: 30-50 kgf / cm ² ×: 10-30 kgf / cm ² Surface water volume fluctuation resistance of fine aggregate The amount of change in slump flow when the surface water content of fine aggregate changed from + 1% to -1% was measured. The evaluation criteria are as follows.

(Slump flow at a surface water rate of +1%)-(Slump flow at a surface water rate of -1%) = change (cm) ：: change <7 cm Δ: change 7 cm to 15 cm ×: Table 5 shows the results when the amount of change is greater than 15 cm. In addition, non-adsorption type thickener (a-1)
Was 0.7 in terms of% by weight of cement (effective amount), and the addition amount of the polysaccharide derivative (a-2) and the comparative admixture was 0.02 in terms of% by weight (effective amount) of cement. The amount of the high-performance water reducing agent is shown in% by weight of cement (effective component).

[0055]

[Table 5]

From the above results, since the hydraulic composition of the present invention has a high fluidity with a slump flow value of about 60 cm and excellent separation resistance, a sufficiently satisfactory self-filling result can be obtained. It turns out that it is possible. As for the cured physical properties, good results were obtained in one-day strength.
The change in fluidity with respect to the fluctuation of the surface water amount of fine aggregate is small. On the other hand, in the case of the comparative admixture, when the addition amount is 0.02 by weight of cement, sufficient separation resistance cannot be obtained, and excellent self-filling property is not obtained although the fluidity is high.
In addition, good results have not been obtained with respect to cured physical properties and surface water volume fluctuation resistance.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C04B 24/32 C04B 24/32 A 28/04 28/04 // C04B 103: 32 111: 20

Claims (6)

[Claims] 1. Adsorption characteristic for cement is 10%
Less than a water-soluble polymer (a-1), wherein some or all of the hydrogen atoms of the hydroxyl groups of the polysaccharide or an alkylated or hydroxyalkylated derivative thereof have a hydrocarbon chain having 8 to 40 carbon atoms as a partial structure Ionic hydrophilic substitution containing, as a partial structure, a hydrophobic substituent (A) and at least one group selected from the group consisting of a sulfonic acid group, a carboxyl group, a phosphate group, and a sulfate group, and salts thereof. An additive for a hydraulic composition, comprising a polysaccharide derivative (a-2) substituted with the group (B) and a high-performance water reducing agent (b). 2. The method according to claim 1, wherein the water-soluble polymer (a-1) contains 6 to 3 molecules in the molecule.
Monohydric alcohol having 0 carbon atoms, 6 to 3 in the molecule
Monovalent mercaptan having 0 carbon atoms, 6 in the molecule
Alkylphenols having up to 30 carbon atoms, amines having 6 to 30 carbon atoms in the molecule, or 6 to 30 carbon atoms in the molecule
The additive for a hydraulic composition according to claim 1, which is a polyalkylene oxide derivative obtained by adding 10 to 1000 moles of an alkylene oxide to a carboxylic acid having 30 carbon atoms. 3. An alkyl glyceryl ether group having a linear or branched alkyl group having 8 to 40 carbon atoms, or an alkenyl glyceryl having a linear or branched alkenyl group having 8 to 40 carbon atoms, wherein the hydrophobic substituent (A) has 8 to 40 carbon atoms. An ether group or a hydroxyl group, which may be substituted and may have an oxycarbonyl group inserted, and may be a linear or branched alkyl group having 8 to 40 carbon atoms, an alkenyl group or an acyl group, Or more groups, wherein the ionic hydrophilic substituent (B) has 1 carbon atom which may be substituted by a hydroxyl group.
And at least one selected from the group consisting of a sulfoalkyl group, a carboxyalkyl group, an alkyl phosphate group, and a sulfate ester alkyl group and salts thereof, wherein the degree of substitution by the hydrophobic substituent (A) is Per constituent monosaccharide residue
The additive for a hydraulic composition according to claim 1 or 2, wherein the additive is 0.0001 to 1 and the degree of substitution by the ionic hydrophilic substituent (B) is 0.001 to 2 per constituent monosaccharide residue. 4. The high-performance water reducing agent (b) is a monomer selected from the group consisting of a monomer represented by the following general formula (1) and a compound represented by the following general formulas (2) and (3): The additive for a hydraulic composition according to any one of claims 1 to 3, which is a water-soluble vinyl copolymer having an oxyalkylene group obtained by polymerizing the above monomer. Embedded image [Wherein R ₁ , R ₂ : hydrogen atom or methyl group m ₁ : number of 0 to 2 AO: oxyalkylene group having 2 to 3 carbons n: number of 1 to 300 X: hydrogen atom or 1 to carbon atoms 3 represents an alkyl group. ] [Wherein, R ₃ , R ₄ , R ₅ : hydrogen atom, methyl group or (C
H ₂ ) m ₂ COOM ₂ R ₆ : hydrogen atom or methyl group M ₁ , M ₂ , Y: hydrogen atom, alkali metal, alkaline earth metal, ammonium, alkyl ammonium or substituted alkyl ammonium m ₂ : number of 0 to 2 Represents ] 5. A hydraulic composition comprising the hydraulic composition additive according to claim 1 and a hydraulic powder, wherein the water-soluble polymer (a-1) is based on the hydraulic powder. 0.05 to 1.0% by weight, polysaccharide derivative (a-2) 0.0001 to 3% by weight, high performance water reducing agent (b)
A hydraulic composition added in an amount of 0.1 to 5% by weight. 6. The hydraulic composition according to claim 5, further comprising an aggregate.