KR101357456B1 - Concrete thickener for anti-washout property and method for the production thereof - Google Patents

Abstract

The present invention relates to a water-incombustible admixture composition for concrete and a method for preparing the same, and in particular, a mixed surfactant and a polymer thickener including an anionic surfactant and a cationic surfactant. Such a concrete admixture composition is excellent in water inseparability, excellent filling properties and self-leveling properties, there is an effect that can facilitate the pumping during pouring work. In addition, the concrete mortar using the admixture composition according to the present invention has excellent flow characteristics when admixing, excellent workability, and even when pouring, the pour water is not separated into the water by the thixotropy characteristics and does not flow into the water. At the time of hardening, the hardness shows the outstanding characteristic.

Description

Concrete thickener admixture composition for concrete and its manufacturing method {Concrete thickener for anti-washout property and method for the production approximately}

The present invention relates to a admixture composition for concrete and a method for producing the same, in particular, admixture composition for concrete excellent in water inseparability, excellent filling and self-leveling properties, and can facilitate pumping during pouring To provide a concrete mortar comprising this.

When applying concrete mortar including concrete admixture to bridge piers, underwater structures, or tunnel construction, even if mortar is placed in water, the flow material and mortar are better so that the pouring material does not disperse into the water and exhibits high fluidity. Filled physical properties should be excellent. This property of concrete mortar is called anti-washout property and self-leveling property.

In addition, when the concrete admixture is made of mortar mixed with aggregate and sand, it should maintain the appropriate viscosity so that the separation phenomenon due to the specific gravity difference is small. Sedimentation of high specific gravity minerals is generally explained by the Stokes equation (settle rate v = 2r ² Δρg / 9η, where Δρ = density difference between two phases, r = radius of particles, η = viscosity). It should be maintained to reduce phase separation due to sedimentation of the inorganic particles.

Conventionally, the method of increasing the viscosity and fluidity of concrete includes first, using a thickener, second, controlling the thickening effect by controlling the hydrophilicity and hydrophobicity of the dispersant, and third, applying a pseudo-polymer thickening system. Methods of controlling the rheological properties of are known.

In the method using the thickener, a commonly used thickener is methyl cellulose (methylcellulose), which corresponds to a polysaccharide type thickening agent. These thickeners are difficult to control the viscosity change with the application amount, and it may take a long time for the powder particles to melt completely to have a thickening effect, which may cause a delay in casting work.

The method of controlling the thickening effect by controlling the hydrophilicity and hydrophobicity of the dispersant is known to have a strong method of increasing the molecular weight or introducing a functional group having a thickening force to increase the thickening effect. In the case of tetra polyethylene oxide-propylene oxide ethylene diamine prepared by reacting ethylene oxide and propylene oxide with ethylenediamine ( ₂ HN-CH ₂ CH ₂ -NH ₂ ) as a dispersant, increasing the ethylene oxide content increases hydrophilicity and propylene oxide. Increasing the content increases hydrophobicity. At this time, if the ethylene oxide content is properly increased and the molecular weight is increased, the thickening effect is increased, and if the propylene oxide content is increased, the hydrophobicity is improved, and the wetting ability can be increased. In other words, the selection of the appropriate hydrophilic and hydrophobic groups enables the simultaneous realization of the thixotropic properties of the dispersed phase and the inseparable properties of the water.

The pseudo-polymer thickening system uses a phenomenon in which a molecular weight increases due to an electrostatic attraction between two kinds of surfactants (mainly an anionic surfactant and a cationic surfactant mixture), and in some cases, There is a disadvantage in that the pumping characteristics are inferior due to a sharp increase in viscosity. Thus, the most viable method is to use a common thickener and a pseudo-polymer thickening system.

As a related patent, US Patent 2011-0046270 A1 uses a mixture of a polycarboxylic acid type sensitizer, a hydroxycarboxylic acid type sensitizer, and a polysaccharide type thickener to mix concrete high fluidity, pumping force, reinforcement strength, and water inseparability. This method of producing an optimal concrete admixture is introduced. In addition, US Patent 1999-5921319 claims Portland cement and bentonite as a thickening agent, and claims an environmentally friendly cement composition having excellent water-inseparable properties by blending oils of vegetable oils.

Japanese Patent 2002-188911 B2, 2002-331377 B2, 1997-188554 A discloses a manufacturing technique for a highly flexible concrete admixture composition composed of vinyl carboxylate and naphthalene sulfonate. Japanese Patent 2002-3306255 also discloses a concrete admixture composition containing a carboxylic acid copolymer and sodium gluconate, glucose, dextrin, sucrose, sorbitol, and the like.

Korean Patent No. 2011-0073507 discloses a multi-branched polyalkylene glycol-based polymer comprising a polyalkylene glycol chain and a cement admixture and a cement composition manufacturing technology using the same. Korean Patent No. 2006-0112748 discloses low molecular weight silane based sulfate resistant cement, coarse aggregate with particle size below 25mm, siliceous fine aggregate with 2.92% of granules free of salt components, sulfonated aluminum carbonate (CSA) expander, lignin-based fluidizing agent and An underwater concrete composition composed of water and a water reducing agent is introduced.

According to the above, most conventional concrete admixture compositions use a large amount of high molecular compound of the hydrophilic group in the main chain, such as polycarboxylic acid or polycellulose compound. In comparison, the use of pseudo-polymer thickening system is not known much.

The present invention is to solve the above problems, an object of the present invention is to provide an admixture composition for concrete that is excellent in water inseparability, excellent filling and self-leveling properties, and can facilitate pumping during pouring work. .

In addition, the present invention is excellent in flow characteristics when mixing with concrete, excellent workability, and even when pouring, the pouring does not flow into the water due to thixotropy characteristics, and excellent hardness when hardening To provide concrete mortar with properties.

Concrete admixture composition according to the present invention for achieving the above object is an anionic surfactant; Cationic surfactants; And a polymeric thickener.

Meanwhile, another embodiment of the present invention may be concrete mortar including the admixture composition for concrete, concrete and sand.

Further, another embodiment of the present invention, the step of dissolving an anionic surfactant and a cationic surfactant in water and stirring for 30 minutes to 120 minutes at 40 ~ 50 ℃ to prepare a mixed surfactant solution; And adding a polymeric thickener to the prepared mixed surfactant solution and then stirring the mixture for 30 to 60 minutes at 30 to 50 ° C.

The details of other embodiments are included in the detailed description and drawings.

The admixture composition for concrete according to the present invention is characterized in that it comprises a mixed surfactant and a polymer thickener including an anionic surfactant and a cationic surfactant, it is excellent in water inseparability, excellent filling and self-leveling properties In addition, there is an effect that can facilitate the pumping during pouring work.

In addition, the concrete mortar using the admixture composition according to the present invention has excellent flow characteristics when admixing, excellent workability, and even when pouring, the pour water is not separated into the water by the thixotropy characteristics and does not flow into the water. At the time of hardening, the hardness shows the outstanding characteristic.

1 is a photograph of the results of the evaluation of the water inseparability of the admixture composition for concrete prepared by the Examples and Comparative Examples according to the present invention ((a): Example 5, (b): Example 10, ( c): Comparative Example 1, (d): Comparative Example 3),
2 is a graph showing the results of comparative evaluation of Rheology properties of the admixture composition for concrete prepared by Examples and Comparative Examples according to the present invention (A: Comparative Example 3, B: Example 10).

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and will be described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "having" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

The present invention is an anionic surfactant; Cationic surfactants; And a polymer thickener;

The present invention relates to a mixed admixture composition for concrete in which a mixed surfactant including an anionic surfactant and a cationic surfactant and a polymer thickener are blended, and use a pseudo-polymer thickening system made by the mixed surfactant. It is characterized by controlling the rheological properties of concrete mortar or cement admixture by mixing and using a mixed micelle phenomenon with a mixed surfactant and a polymer thickener.

In general, surfactants form spherical micelles in aqueous solution and, as their concentration increases, they cause phase transitions into rodlike micelles. Even when ionic surfactants having different electrical properties meet in an aqueous solution, the viscosity of the micelle is changed to a lamellar structure. The present inventors added a polymeric thickener to the mixed surfactant, which has the effect that the mixed surfactant aggregates together into a spherical micelle rather than a rod micelle, thereby preventing the viscosity from being increased like excessive Newtonian fluid and at the same time improving the flowability. The present invention was completed after confirming that the dispersion, viscosity, fluidity, and fillability were changed.

The present invention is a concrete admixture blended with a mixed surfactant and a polymer thickener, has excellent flow characteristics when mixing concrete, excellent workability, and when poured, the pours are separated in water by thixotropy properties. It is a new functional thickener that does not flow down and increases hardness when cured.

Specifically, the anionic surfactants are sodium dodecyl sulfate, linear alkyl benzene sulphonate, sodium lauryl ether sulfate, sodium xylene sulphonate, and It is preferably one or more selected from the group consisting of sodium naphthalene sulphonate, and more preferably sodium sulfonate xylene.

In addition, the cationic surfactant is cetyl trimethyl ammonium chloride (CTAC), polyquaternium-11 (poly quaternium-11), polyethylene glycol monostearate and ester quaternary ammonium salt ( Ester quatenary ammonium salt) is preferably at least one selected from the group consisting of, more preferably cetyl trimethyl ammonium chloride.

The anionic surfactant and cationic surfactant are preferably included in a weight ratio within the range of 3: 1 to 1: 3. If the anionic surfactant and the cationic surfactant are out of the range, it is difficult to form spherical micelles in an aqueous solution and the viscosity increases rapidly.

In addition, the polymer thickener is a group consisting of poly vinyl acetate, poly vinyl methyl ether, poly vinyl chloride, and poly methyl methacrylate. It is preferable that it is at least one selected from among them, and more preferably, polyvinyl methyl ether.

The polymeric thickener is preferably included in the range of 0.1 to 10 parts by weight based on 1 part by weight of the surfactant including the anionic surfactant and the cationic surfactant. When the polymer thickener content exceeds the range, the viscosity change is increased. If it is difficult to control, and less than the above range, the effect of flocculating the mixed surfactant into the spherical micelles is lowered, there is a disadvantage that the flowability worsens.

Along with this, the admixture composition for concrete according to the present invention may further include a solubilizer for mixing the cationic surfactant and the anionic surfactant.

The solubilizer may be at least one selected from the group consisting of ethanol, isopropyl alcohol, ethylene glycol, propylene glycol, sorbitol and glycerin.

Meanwhile, another embodiment of the present invention may be concrete mortar including the admixture composition for concrete, concrete and sand.

Here, the admixture composition is preferably included in the range of 0.1 to 5.0% by weight based on the entire concrete mortar.

Further, another embodiment of the present invention, the step of dissolving an anionic surfactant and a cationic surfactant in water and stirring for 30 minutes to 120 minutes at 40 ~ 50 ℃ to prepare a mixed surfactant solution; And adding a polymeric thickener to the prepared mixed surfactant solution and then stirring the mixture for 30 to 60 minutes at 30 to 50 ° C.

That is, first, a high concentration of anionic surfactant is dissolved in water, at which time a small amount of solubilizer can be added. And it is preferable to make it stir at 40-50 degreeC for 30 minutes or more so that foam does not generate | occur | produce. After that, the cationic surfactant is added and stirred at 40-50 ° C. for at least 30 minutes to ensure complete mixing.

Then, a small amount of the polymeric thickener is added to the mixed surfactant solution thus prepared, and then stirred at 30 to 50 ° C. for at least 30 minutes to prepare a admixture composition for concrete according to the present invention.

Concrete mortar according to the present invention may be prepared by adding cement (density 3.22 g / cm ³ , specific surface area 2,800 cm ² / g) and / or sand to the admixture composition for concrete prepared as described above.

The present invention may be better understood by the following examples, which are for the purpose of illustrating the invention and are not intended to limit the scope of protection defined by the appended claims.

Example  : Mixed Surfactants and Polymers Increasing agent  Admixture composition for concrete using Mortar  Produce

12.5 g of anionic surfactant sodium xylene sulfonate (SXS, 40%, Sigma-Aldrich) and 20.0 g of cationic surfactant Cethyl trimethyl ammonium chloride (CTAC, 25%, Sigma-Aldrich) were added to a 100 ml beaker and stirred at 45 ° C. The mixture was raised by 20 rpm per minute, stirred for 30 minutes, and then thoroughly mixed to prepare a mixed surfactant solution. At this time, five samples (Examples 1-5) were prepared, changing from anionic surfactant: cationic surfactant = 3: 1 to 1: 3.

SXS: CTAC Additive addition amount to mortar (water / cement = 50%) Example 1 1: 3 1wt Example 2 1: 2 1wt Example 3 1: 1 1wt Example 4 2: 1 1wt Example 5 3: 1 1wt

Then, 0.25 wt%, 0.5 wt%, 1.25 wt%, 5 wt% of polyvinyl methyl ether (PVME, 50%) as a polymer thickener was added to the five mixed surfactant solution samples prepared above at 45 ° C. Completely dissolved.

SXS: CTAC: PVME Additive addition amount to mortar (water / cement = 50%) Example 6 1: 2: 1 1wt Example 7 1: 2: 0.5 1wt Example 8 1: 2: 0.25 1wt Example 9 1: 2: 0.1 1wt Example 10 1: 2: 0.05 1wt

Thereafter, concrete mortar was prepared using the concrete admixtures of Examples 1 to 10 prepared as described above. Concrete mortar was prepared by mixing 1g each of the concrete admixtures of Examples 1 to 10 in 33.3g of water, and stirring the mixture at 300 rpm for 5 minutes at room temperature, and then adding 66.7g of cement and mixing for 1 minute using a hand mixer. It was.

Comparative Example  : Conventional concrete Mortar  Produce

As Comparative Example 1, concrete mortar was prepared using only water (33.3 g) and cement (66.7 g) without using a concrete admixture.

In Comparative Examples 2 and 3, concrete mortar was prepared by using 0.5 wt% and 1 wt% of a commercially available concrete admixture 'VIS' manufactured by 'K' of Japan in water / cement = 50% of mortar. The 'VIS' composition is composed of alkyl aryl sulfonate and alkyl ammonium salt.

Experimental Example  : Check Property Comparison

As an experiment to check the water separation characteristics, 850ml of water was filled at 18 ° C. or more in a water tank made of acrylic 15cm wide, 4.5cm high and 20cm high.

The concrete mortar used in the experiment was mixed with 49.95 g of water and 1.5 g of each concrete admixture composition prepared according to the above examples and comparative examples in a 250 ml Bayer bottle, and shaken well for 20 s by hand mixing, followed by 99.9 g of cement. After shaking well for 1 min, it was slowly added to the prepared water tank to visually check the material separability in the water.

The inseparability in water was evaluated as 10 points for samples where the components were not dispersed in water at the time of mortar injection, and 0 points for samples mixed in water completely. In addition, fluidity has the physical meaning of the inverse of the viscosity, and when the mortar is poured into water, it is viscoelastic, so that the sample represents 10 points of fluid flow and 0 points of no fluid flow at all. Comparative evaluation was carried out as follows. Pumping force-filling-self leveling characteristics were visually determined.

[Underwater inseparability]

10 points: excellent 8 points: good,

6 points: moderate 4 points: bad,

2 points: very poor, 0 points: completely mixed with water

[liquidity]

10 points: excellent fluidity like fluid (> 2 X 10 ^-5 mPas ^-1 )

8 points: good fluidity (2 X 10 ^-5 to 1 X 10 ^-5 mPas ^-1 )

6 points: moderate fluidity (1 X 10 ^-5 to 8 X 10 ^-6 mPas ^-1 )

4 points: bad fluidity (6 X 10 ^-6 to 8 X 10 ^-6 mPas ^-1 )

2 points: very poor fluidity (8 X 10 ^-6 to 4 X 10 ^-6 mPas ^-1 )

0 points: completely disconnected due to high viscosity (> 10 ^-6 mPas ^-1 )

[Pumping force-filling-self leveling]

10 points: excellent 8 points: good

6 points: moderate 4 points: bad

2 points: poor 0 points: very poor

)에 넣고 Brookfield viscometer (Thermo, Viscotester 7plus)를 이용하여 측정하였다. 이러한 Brookfield viscometer의 stick 3호 (

)를 투입선까지 콘크리트에 투입하여 점도를 측정하였다. 10min 기준으로 30,000mPan 미만의 경우 4rpm의 회전속도로20℃이상에서 측정하였으며, 30,000mPas 최과할 경우 1rpm의 회전속도로 20℃이상에서 측정하였다. 상황에 따라 rpm의 한계 점도측정 90% 이상, 10% 이하의 경우 ±1 rpm으로 조정하였다.In order to measure the viscosity, 33.3 g of water and 1.0 g of each concrete admixture composition prepared according to the above examples and comparative examples were added to a 250 ml Bayer bottle, shaken well for 20 seconds by hand mixing, and then 66.6 g of cement was added. Shake well for 1 minute and mix 25ml of concrete with a clear glass

) Was measured using a Brookfield viscometer (Thermo, Viscotester 7plus). Stick 3 of the Brookfield viscometer (

) Was added to the concrete up to the input line to measure the viscosity. In case of less than 30,000mPan, it was measured at 20 ° C or higher at a rotational speed of 4rpm on a 10min basis. According to the situation, the limit viscosity measurement of rpm was adjusted to ± 1 rpm for 90% or more and 10% or less.

In addition, in order to measure the rheological properties, 33.3 g of water and 1.0 g of each concrete admixture composition prepared according to the above Examples and Comparative Examples were added to a 250 ml Bayer bottle, and shaken well for 20 s by hand mixing, followed by 66.6 g of cement. The mixture was shaken well for 1 minute by hand mixing and analyzed using a rotational rheometer.

In order to find out the exact flow resistance of this concrete, as the analysis conditions, how much force is used to move the sample when it is rotated at a constant speed of 0.001 (1 / s) at a temperature of 23 ℃, that is, the flow resistance of concrete with admixture Learned. Analysis time was analyzed for 180 seconds, at which the gap of the sample was measured to 0.3mm.

The results are summarized in Tables 3 and 4 below.

Comparative Example 1 Example 1 Example 2 Example 3 Example 4 Example 5 Viscosity (10min, mPas) 0 85,200 55,790 20,990 44,460 21,300 Viscosity (10min, mPas) 90.8 55,790 84,920 25,490 55,310 35,300 Anti-washout 2 10 10 8 6 6 liquidity 10 6 8 10 10 10 Pumping force-filling 6 6 8 6 6 8

Comparative Example 2 Comparative Example 3 Example 6 Example 7 Example 8 Example 9 Example 10 Viscosity (10min, mPas) 284,670 334,400 1,830 3,210 6,380 10,900 11,820 Viscosity (10min, mPas) 544,680 586,310 3,200 6,710 9,340 31,620 33,500 Anti-washout 4 10 8 8 8 10 10 liquidity 6 4 10 10 10 10 10 Pumping force-filling 6 4 10 10 10 10 10

1 is a photograph of the results of the evaluation of the water inseparability of the admixture composition for concrete prepared by the Examples and Comparative Examples according to the present invention ((a): Example 5, (b): Example 10, ( c): Comparative Example 1, (d): Comparative Example 3), Figure 2 is a graph of the experimental results of comparative evaluation of Rheology properties of the admixture composition for concrete prepared by Examples and Comparative Examples according to the present invention (A: Comparative Example 3, B: Example 10).

The high-performance special thickener used in this comparative experiment is known as the world's best concrete thickener in the field of 'VIS' of Japanese K company, whose main composition is alkyl aryl sulfonate or alkyl ammonium salt blend.

Using the special thickener, water incompatibility, and Brookfield viscometer, the viscosity was measured over time and the flow resistance of the concrete to which the sample was added using the rotational rheometer was compared. The amount of thickener was small at 0.5wt%, which resulted in inadequate separation of water in water.

In addition, when applied to 1.0wt% as shown in Comparative Example 3, it showed a clear underwater separation characteristics as shown in Figure 1, but the inherent viscosity of the concrete is too high, showing very weak results in fluidity and pumping effect.

In comparison, in the case of the embodiment according to the present invention, all of them exhibit excellent physical properties in water inseparability, flowability, pumping force, and the like.

2 is a viscosity characteristic using a rotational rheometer Comparative Example 3 ("A") shows a high viscosity when the Shear takes less, showing weak results in flowability / pumping force, etc., Example 10 ("B") is a comparative example It has thixotropic rheological properties that are very similar to 3, but its viscosity is not so high that it has excellent water-inseparability and excellent properties in fluidity and pumping power.

While the present invention has been particularly shown and described with reference to preferred embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be apparent to those skilled in the art that changes may be made.

Claims (11)

Mixed surfactants including anionic surfactants and cationic surfactants; And
Polyvinyl methyl ether (Poly vinyl methyl ether) as a polymer thickener; Admixture composition for concrete comprising a.
The admixture composition for concrete according to claim 1, wherein the mixed surfactant is agglomerated into spherical micelles by the polyvinyl methyl ether.
The method of claim 1,
The anionic surfactant is sodium xylene sulphonate, and the cationic surfactant is cetyl trimethyl ammonium chloride (CTAC).
Mixed surfactants including anionic surfactants and cationic surfactants; And
Polyvinyl chloride as a polymer thickener; Admixture composition for concrete comprising a.
The admixture composition for concrete according to claim 1, further comprising a solubilizer.
6. The admixture composition for concrete according to claim 5, wherein the solubilizer is at least one selected from the group consisting of ethanol, isopropyl alcohol, ethylene glycol, propylene glycol, sorbitol, and glycerin.
The admixture composition for concrete according to claim 1, wherein the anionic surfactant and the cationic surfactant are included in a weight ratio within the range of 3: 1 to 1: 3.
The admixture composition for concrete according to claim 1, wherein the polymeric thickener is included in the range of 0.1 to 10 parts by weight based on 1 part by weight of the mixed surfactant.
Concrete mortar comprising admixture composition according to any one of claims 1 to 8, concrete and sand.
The concrete mortar of claim 9, wherein the admixture composition is included in a range of 0.1 to 5.0 wt% based on the total concrete mortar.
Preparing a mixed surfactant solution by dissolving anionic surfactant and cationic surfactant in water and stirring at 40-50 ° C. for 30 minutes to 120 minutes; And
And adding polyvinyl methyl ether as a polymer thickener to the prepared mixed surfactant solution, and then stirring the mixture at 30 to 50 ° C. for 30 to 60 minutes.

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