KR100904607B1 - Cement admixture, preparation method thereof, and cement composition containing the same - Google Patents

Abstract

The present invention relates to a cement admixture, and more particularly to at least one member selected from the group consisting of a carboxylic acid copolymer comprising a polyoxyalkylene alkenylether sulfate salt as a reactive monomer, and a salt thereof. It relates to a cement admixture, characterized in that the manufacturing method, and a cement composition comprising the same.

According to the present invention, the initial dispersibility is improved compared to the conventional cement admixture to improve the initial susceptibility, improve the fluidity of the composition even in the region of high susceptibility, improve the cure delay early to express the strength and at the same time lower the fluidity By preventing the imparting good workability to the cement composition has the effect of forming a concrete having a high strength early.

Cement admixtures, alkoxypolyalkylene glycol mono (meth) acrylic acid esters, (meth) acrylic acid, polyoxyalkylene alkenylether sulfate salts, dispersibility, fluidity, compressive strength

Description

Cement admixture, preparation method thereof, and cement composition comprising the same {CEMENT ADMIXTURE, PREPARATION METHOD THEREOF, AND CEMENT COMPOSITION CONTAINING THE SAME}

The present invention relates to a cement admixture, and more particularly, to improve initial susceptibility due to excellent initial dispersibility compared to conventional cement admixtures, improve flowability of the composition even in a region of high susceptibility, and improve curing delay. The present invention relates to a cement admixture, a method for preparing the same, and a cement composition including the same, wherein the cement admixture is capable of forming a concrete having high strength by providing good workability to the cement composition by preventing a decrease in fluidity while simultaneously exhibiting strength.

Cement compositions, such as concrete or mortar, are hydraulic reactants that are cured by the reaction of cement and water, and have different physical properties such as compressive strength after curing depending on the amount of water used. In general, an increase in the amount of water used improves workability, but decreases the compressive strength and causes cracks, so that the amount of water used for the cement composition is limited, and in accordance with Korean Industrial Standard KS F 2560 to reduce the amount of water used. As will be described later, a chemical admixture for concrete is used.

The types of chemically synthesized admixtures are roughly classified into air entraining admixtures, water reducing admixtures, and high range water reducing admixtures. In addition, the AE agent, which is a chemical admixture used in cement compositions to increase the amount of fine air, is classified into an air entraining and water reducing admixture and a high performance AE water reducing agent by mixing with a water reducing agent or a high performance water reducing agent. When the AE water reducing agent is used, the amount of water used may be reduced by about 10% by weight, and in the case of the high performance AE water reducing agent, the weight may be reduced by 18% or more.

The concrete in the cement composition usually had a slump drop after 30 minutes and had to finish all the work in a short time from concrete mixing to casting. In response to the recent trend of increasing the number of units due to the deterioration of the quality of concrete aggregates, the use of modern mechanized equipment and traffic congestion have a higher sensitivity than conventional AE water reducing agents, or a chemical admixture with excellent slump retention performance Has been required. As a admixture of hydraulic compositions such as cement and concrete, it has a high sensitivity and fluidity, and has an excellent slump retention, and is currently naphthalene sulfonic acid formaldehyde condensate salt (naphthalene-based), melamine sulfonic acid formaldehyde condensate salt (melamine), poly High performance AE water reducing agents, such as a carboxylic acid salt (polycarboxylic acid type), are used.

Each of these high performance sensitizers has excellent features, but there are also problems. For example, naphthalene-based or melamine-based have excellent curing properties but have problems in flow retention (slump), whereas polycarboxylic acids have the advantage of being able to obtain very good fluidity and retention with only a small amount of addition. There is a problem that the curing delay is large.

In recent years, cement admixtures have been developed that improve the problem of delayed curing of polycarboxylic acid-based water-reducing agents, exhibit high susceptibility and sufficient fluidity, and also express high strength early by shortening condensation time, thereby enabling high workability and shortening construction period. Has been. In particular, since the mid-1990s, water-soluble vinyl copolymer high performance AE water reducing agents having excellent dispersion characteristics using the steric repulsion of oxyalkylene groups and shortening the setting time have been proposed. Examples of such vinyl copolymers include copolymers of polyalkylene glycol mono (meth) acrylic acid ester monomers and dicarboxylic acid monomers such as (meth) acrylic acid or maleic acid.

Japanese Patent Application Laid-open No. Hei 8-12396 (published Jan. 16, 1996) and the like mention a correlation between the cure delay of an carboxylic acid-based concrete admixture and an oxyalkylene group, and added to the polyalkylene glycol monoester monomer. It is described that an oxyalkylene group is excellent in hardening characteristic in a specific range. These cement admixtures have an effect of improving curing delay to some extent by increasing the number of moles of alkylene oxide compared with conventional polycarboxylic acid admixtures, but the slump retention is not satisfactory and the early strength properties are not sufficient yet. As a result, more performance is required.

Further, Japanese Patent Laid-Open No. 9-132445 (published on May 20, 1997) discloses a cement admixture composed of a polymer of a diester monomer to which 2 to 300 moles of an oxyalkylene group is added and a maleic acid dicarboxylic acid monomer. Japanese Laid-Open Patent Publication No. 9-241057 (published on September 16, 1997) discloses a cement admixture in which an end of a polyalkylene glycol monomer to which an oxyalkylene group is added in the range of 100 to 300 moles is composed of an alkyl phenol group. . This kind of water reducing agent has to be added in a large amount in order to exhibit sufficient dispersibility and slump retention, and the problem that the fluidity of the cement composition decreases rapidly with time in comparison with the effect of reducing the curing delay has not been solved.

Japanese Patent Application Laid-Open No. 11-157897 (published on June 15, 1999) discloses two types of polyalkylene glycol (meth) acrylic acid esters, each having an added molar number of 80 to 300 moles and 5 to 30 moles of added oxyalkylene groups. Disclosed is a copolymer cement admixture having monomers and (meth) acrylic acid salts or dicarboxylic acid monomers as essential components and improving curing delay without increasing viscosity.

Although the water reducing agent composed of the above water-soluble vinyl copolymer has an effect of reducing the curing delay of the cement composition to shorten the construction period, in order to shorten the setting time, the added mole number of the oxyalkylene group is too high, and the initial susceptibility is excellent. A large amount of addition is required in order for the slump holding force of the cement composition to drop rapidly to maintain sufficient dispersibility.

Therefore, in order to improve the curing time delay and to express the work strength early and to satisfy the excellent slump holding force, further improvement of the performance of the cement admixture is required.

In order to solve the problems of the prior art as described above, the present invention is excellent in initial dispersibility compared with the conventional cement admixture to improve the initial susceptibility, improve the fluidity of the composition in the region of high susceptibility, and improve the curing delay It is an object of the present invention to provide a cement admixture capable of forming concrete having high strength early by providing good workability to the cement composition by simultaneously expressing strength at the same time and preventing fluidity deterioration.

In addition, an object of the present invention is to provide a cement composition comprising the cement admixture.

The above and other objects of the present invention can be achieved by the present invention described below.

In order to achieve the above object, the present invention

a) 50 to 95% by weight of an alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer represented by Formula 1 below, wherein the average added mole number of the oxyalkylene group is an integer of 50 to 200;

b) 1 to 20% by weight of an alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer represented by Formula 1 below, wherein the average added mole number of the oxyalkylene group is an integer of 10 to 30;

c) 3 to 45 wt% of a (meth) acrylic acid monomer or salt thereof represented by Formula 2; And

d) a cement comprising at least one member selected from the group consisting of carboxylic acid-based copolymers polymerized from 0.5 to 20% by weight of a polyoxyalkylene alkenylether sulfate salt represented by the following formula (3), and salts thereof: Admixtures, and methods for their preparation are provided.

[Formula 1]

In Chemical Formula 1,

R ¹ is a hydrogen atom or methyl,

R ² O is one kind or a mixture of two or more kinds of oxyalkylenes having 2 to 4 carbon atoms, and in the case of two or more kinds, R ² O may be added in a block or random phase,

R ³ is alkyl having 1 to 4 carbons,

m is the average added mole number of an oxyalkylene group.

[Formula 2]

In Chemical Formula 2,

R ⁴ is a hydrogen atom or methyl,

M ¹ is a hydrogen atom, a monovalent metal, a divalent metal, ammonium or an organic amine.

[Formula 3]

In Chemical Formula 3,

R ⁵ is a hydrogen atom or methyl,

R ⁶ is alkylene, phenylene or alkylphenylene having 1 to 3 carbon atoms,

R ⁷ is one kind or a mixture of two or more kinds of oxyalkylenes having 1 to 4 carbon atoms, and in the case of two or more kinds, R ⁷ may be added in a block or random phase,

n is an integer of 10 to 50 as the average added mole number of the oxyalkylene group,

M ² is a hydrogen atom, a monovalent metal, ammonium or an organic amine.

In addition, the present invention provides a cement composition comprising 0.01 to 10 parts by weight of the cement admixture based on 100 parts by weight of cement.

Hereinafter, the present invention will be described in detail.

The present inventors include a polyoxyalkylene alkenylether sulfate salt as a reactive monomer as a unit monomer in a copolymer having a carboxylic acid monomer as a basic skeleton, and alkoxypolyalkylenes having different average added moles of oxyalkylene groups. Cement admixtures prepared by graft copolymerization of glycol mono (meth) acrylic acid ester monomers are compared with cement admixtures prepared by graft copolymerization of alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomers alone and conventional cement admixtures. It is excellent in dispersibility and improves the flowability of cement composition even in the region of high susceptibility, and greatly improves the curing delay, so that the cement composition can show strength early and shorten the construction period, and prevent the deterioration of fluidity over time. Continuous air volume at the same time To operate as was confirmed to impart good workability to the cement composition, and completed the present invention based on this.

The carboxylic acid copolymer of the present invention comprises a) 50 to 95% by weight of an alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer having an average added mole number of an oxyalkylene group represented by the formula (1), an integer of 50 to 200, b) 10-20% by weight of an alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer having an average added mole number of an oxyalkylene group represented by formula (1), which is an integer of 10 to 300, c) (meth) acrylic acid monomer represented by formula (2) Or 3 to 45% by weight of the salt thereof, and c) 0.5 to 20% by weight of the polyoxyalkylene alkenylether sulfate salt represented by the formula (3).

The alkoxy polyalkylene glycol mono (meth) acrylic acid ester monomer represented by General formula (1) of a) and b) is methoxy polyethyleneglycol mono (meth) acrylate, methoxy polypropylene glycol mono (meth) acrylate, and methoxy Polybutylene glycol mono (meth) acrylate, methoxy polyethylene glycol polypropylene glycol mono (meth) acrylate, methoxy polyethylene glycol polybutylene glycol mono (meth) acrylate, methoxy polypropylene glycol polybutylene glycol mono (Meth) acrylate, methoxy polyethylene glycol polypropylene glycol polybutylene glycol mono (meth) acrylate, ethoxy polyethylene glycol mono (meth) acrylate, ethoxy polypropylene glycol mono (meth) acrylate, ethoxy poly Butylene glycol mono (meth) acrylate, ethoxy polyethylene glycol polypropylene glycol mono ( (2) acrylate, ethoxy polyethylene glycol polybutylene glycol mono (meth) acrylate, ethoxy polypropylene glycol polybutylene glycol mono (meth) acrylate, or ethoxy polyethylene glycol polypropylene glycol polybutylene glycol mono ( Methacrylate, etc. may be selected, and these may be copolymerized alone or in mixture of two or more kinds.

a) The alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer is preferably an integer of 50 to 200, and more preferably an integer of 50 to 150, on average of an oxyalkylene group. When the average added mole number of the oxyalkylene group is an integer of 50 to 200, there is an effect of improving the initial susceptibility, improving the curing delay, and expressing high strength early.

Preferably, the a) alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer having an average added mole number of the oxyalkylene group is an integer of 50 to 200, preferably contained in an amount of 50 to 95% by weight based on the total content of the carboxylic acid copolymer. If the content is 50 to 95% by weight, there is an excellent dispersibility effect.

b) It is preferable that the average addition mole number of an oxyalkylene group is an integer of 10-30, and, as for an alkoxy polyalkylene glycol mono (meth) acrylic acid ester monomer, More preferably, it is an integer of 10-25. When the average added mole number of the oxyalkylene group is an integer of 10 to 30, there is an effect of sustaining the initial susceptibility and the holding power.

B) The alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer having an average added mole number of the oxyalkylene group is an integer of 10 to 30 is preferably contained in 1 to 20% by weight based on the total content of the carboxylic acid copolymer. If the content is 1 to 20% by weight, the holding force is excellent.

c) As the (meth) acrylic acid monomer represented by the formula (2), acrylic acid, methacrylic acid, and monovalent metal salts, divalent metal salts, ammonium salts and organic amine salts thereof may be selected, and these may be used alone or in combination of two or more. May be mixed and copolymerized.

C) The monomer represented by the formula (2) is preferably included in 3 to 45% by weight in the total content of the carboxylic acid-based copolymer. When the content is 3 to 45% by weight, there is an effect of improving the slump loss preventing ability of the cement composition.

d) The polyoxyalkylene alkenyl ether sulfate salt represented by the formula (3) is a reactive surfactant which is included as a unit monomer in the carboxylic acid-based copolymer and has both hydrophobic and hydrophilic groups to increase the water solubility of the polymer. When the number of moles of alkylene oxide groups added to the polyalkylene glycol ester monomer is increased to accelerate the setting time through the action of increasing the properties that can cause physical adsorption, which helps to maintain the dispersibility of the cement particles. It suppresses the deterioration of fluidity of the cement composition generated over time to maintain the slump retention.

In addition, the d) polyoxyalkylene alkenyl ether sulfate salt represented by the formula (3) has a double bond that can participate in the radical reaction and copolymerizes with the monomers to act as a surfactant in the polymer backbone. The hydrophobic portion of these surfactants aids in the adsorption of cement particles, while the ionic portion forms an electrical double layer to increase zeta potential and increase electrostatic repulsion and stability between dispersed particles. Therefore, the hydrophilicity of the polyalkylene glycol chain and the effect of dispersing cement due to steric repulsion as well as the electrostatic repulsion by the sulfonic acid at the end of the surfactant at the same time is excellent in dispersion and stability of entrained air.

D) As the polyoxyalkylene alkenyl ether sulfate salt represented by the formula (3), sulfoxypolyethylene glycol nonylphenylpropenyl ether, sulfoxypolyethylene glycol allyl ether, sulfoxy polypropylene glycol allyl ether, sulfoxy polybutylene glycol allyl Ether, sulfoxy polyethylene glycol 2-butenyl ether, sulfoxy polypropylene glycol 2-butenyl ether, sulfoxy polybutylene glycol 2-butenyl ether, sulfoxy polyethylene glycol 3-butenyl ether, sulfoxy polypropylene glycol 3-butenyl ether, sulfoxy polybutylene glycol 3-butenyl ether, sulfoxy polyethylene glycol 3-pentenyl ether, sulfoxy polypropylene glycol 3-pentenyl ether, sulfoxy polybutylene glycol 3-pentenyl ether Sulfoxy polyalkylene glycol allyl ethers such as these; Sulfoxypolyethylene glycol (3-vinyl-5-methyl) phenyl ether, sulfoxypolypropylene glycol (3-vinyl-5-methyl) phenyl ether, sulfoxypolybutylene glycol (3-vinyl-5-methyl) phenyl ether , Sulfoxypolyethylene glycol (3-vinyl-5-ethyl) phenyl ether, sulfoxypolypropylene glycol (3-vinyl-5-ethyl) phenyl ether, sulfoxypolybutylene glycol (3-vinyl-5-ethyl) phenyl Ether, sulfoxypolypropylene glycol (3-propenyl-5-propyl) phenyl ether, sulfoxypolybutylene glycol (3-propenyl-5-propyl) phenyl ether, sulfoxypolyethylene glycol (3-propenyl-5 Sulfoxypolyalkylene glycols such as -butyl) phenyl ether, sulfoxypolypropylene glycol (3-propenyl-5-butyl) phenyl ether and sulfoxypolybutylene glycol (3-propenyl-5-butyl) phenyl ether Alkyl vinyl phenyl ethers; 2-sulfoxypolyethylene glycol-3- (4-methylphenoxy) propylene allyl ether, 2-sulfoxy polypropylene glycol-3- (4-methylphenoxy) propylene ether, 2-sulfoxypolybutylene glycol-3 -(4-methylphenoxy) propylene allyl ether, 2-sulfoxypolyethylene glycol-3- (4-ethylphenoxy) propylene allyl ether, 2-sulfoxy polypropylene glycol-3- (4-ethylphenoxy) propylene 2-sulfoxypolyalkylene glycol-3- (4-alkylphenoxy) propylene allyl ethers such as allyl ether and 2-sulfoxypolybutylene glycol-3- (4-ethylphenoxy) propylene allyl ether; And those neutralized with monovalent metals, divalent metals, ammonium salts or organic amines, and the like, and these may be copolymerized alone or in combination of two or more thereof.

D) The polyoxyalkylene alkenyl ether sulfate salt represented by the formula (3) is preferably contained in 0.5 to 20% by weight based on the total content of the carboxylic acid-based copolymer. If the content is 0.5 to 20% by weight, the slump holding force and the appropriate air entrainment of the cement composition has an excellent effect.

The salt of the carboxylic acid copolymer of the present invention is a salt obtained by further neutralizing the carboxylic acid copolymer with an alkaline substance.

The carboxylic acid-based copolymer and salts thereof are preferably 30,000 to 100,000 when the weight average molecular weight is measured by gel permeation chromatography (GPC), more preferably 30,000 to 70,000 in consideration of dispersibility. Do. When the weight average molecular weight is 30,000 to 100,000, the initial dispersibility is excellent to improve the initial susceptibility, not only to maintain the slump retention of the composition, but also to improve the curing delay to form a concrete composition having high strength at an early stage. .

Examples of the carboxylic acid copolymer or the neutralizing salt thereof containing the polyoxyalkylene alkenyl ether sulfate salt of the present invention as a unit monomer may be a copolymer represented by the following formulas 4a and 4b, but are not limited thereto.

[Formula 4a]

[Formula 4b]

In Chemical Formulas 4a and 4b,

M is hydrogen or a monovalent or divalent metal, m, m ', n, o, p, q, and r represent the number of moles, and at least one of m, m' is not 0, and among o, p At least one is not zero and n, q and r cannot be zero.

Method for producing a carboxylic acid-based copolymer of the present invention is a) 50 to 95% by weight of an alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer represented by the formula (1), the average added mole number of the oxyalkylene group is an integer of 50 to 200 b) 1 to 20% by weight of an alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer having an average added mole number of the oxyalkylene group represented by the formula (1), an integer of 10 to 30, c) (meth) represented by the formula (2) 3 to 45% by weight of the acrylic acid monomer or salt thereof, and d) 0.5 to 20% by weight of the polyoxyalkylene alkenylether sulfate salt represented by the formula (3).

The copolymerization method is not particularly limited, and methods such as solution polymerization or bulk polymerization can be used.

When the polymerization initiator is polymerized using water as a solvent, a water-soluble polymerization initiator such as ammonium or an alkali metal persulfate or hydrogen peroxide may be used as a solution polymerization initiator. In addition, in the case of polymerization using a lower alcohol, an aromatic hydrocarbon, an aliphatic hydrocarbon, an ester compound or a ketone compound as a solvent, hydroperoxides such as benzoyl peroxide, lauroyl peroxide, cumene hydroperoxide, or azobisisobutyro Polymerization initiators, such as aliphatic azo compounds, such as a nitrile, can be used, and promoters, such as an amine compound, can be used together. Moreover, when superposing | polymerizing using a water-lower alcohol mixed solvent, it can select suitably from the said polymerization initiator or the combination of a polymerization initiator and an accelerator, and can use.

The polymerization initiator is preferably used in 0.5 to 5% by weight based on the total monomer content.

It is preferable to select the polymerization temperature of the said copolymerization reaction in the range of 0-120 degreeC according to the kind of solvent and polymerization initiator to be used.

In the copolymerization reaction, a thiol-based chain transfer agent may be used together to control the molecular weight of the carboxylic acid-based copolymer prepared. As the thiol-based chain transfer agent, alone or two or more of mercapto ethanol, thioglycerol, thioglycolic acid, 2-mercapto propionic acid, 3-mercapto propionic acid, thioapple acid, thioglycolic acid octyl or 3-mercapto propionic acid octyl It can be mixed and used. Thiol-based chain transfer agent is preferably used in 0.5 to 5% by weight relative to the total monomer content.

The carboxylic acid copolymer prepared by the above method may be used as a main component of a cement admixture as it is, and a copolymer salt obtained by neutralizing with an alkaline substance may be used as a main component of the cement admixture, if necessary.

As the alkaline substance, inorganic substances such as hydroxides, chlorides, carbonates of monovalent metals or divalent metals, ammonia, organic amines, and the like can be used.

The cement composition of the present invention comprises cement and the cement admixture prepared above.

The admixture is preferably included in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of cement, and in particular, 0.1 to 5 parts by weight is more preferable in consideration of the region of high susceptibility. When the content is 0.01 to 10 parts by weight, the performance of dispersibility, water loss, air entrainment, etc. are exerted depending on the content, which is preferable from an economic point of view.

Cement admixture of the present invention exhibits a high susceptibility to improve the dispersibility of cement particles in concrete to reduce the amount of water used by more than 18% by weight, improve the fluidity of the composition even in the region of high susceptibility, and the conventional polycarboxylic acid system Hardening retardation is greatly improved compared to admixtures, which allows the cement composition to develop its work strength early on, but has almost no fluidity deterioration with time, and also works well on the cement composition by continuously running an appropriate amount of air. It has the characteristics of forming concrete with high strength while being able to give a castle.

Hereinafter, preferred examples are provided to aid the understanding of the present invention, but the following examples are merely for exemplifying the present invention, and it will be apparent to those skilled in the art that various changes and modifications can be made within the scope and spirit of the present invention. It is natural that such variations and modifications fall within the scope of the appended claims.

EXAMPLE

Example 1

200 parts by weight of water was injected into a 2 L capacity glass reactor equipped with a thermometer, a stirrer, a dropping funnel, a nitrogen introduction tube and a reflux condenser, and the reaction vessel was replaced with nitrogen and heated to 80 ° C. under a nitrogen atmosphere under stirring.

After adding 2 parts by weight of ammonium persulfate to the reactor and completing the preparation, 270 parts by weight of methoxy polyethylene glycol monomethacrylate (average number of moles of ethylene oxide 55 mol) as a polymerization composition, methoxy polyethylene glycol monomethacrylate (ethylene Average moles of oxide 23 moles) 45 parts by weight, methacrylic acid 34.8 parts by weight, polyoxyethylene nonylphenyl propenyl ether sulfate ammonium salt as nonionic and anionic reactive surfactant (average moles of ethylene oxide 10 moles) 3.5 By weight, a monomer aqueous solution mixed with 95 parts by weight of water, 4.2 parts by weight of 3-mercapto propionic acid and 60 parts by weight of a mixed solution, and 80 parts by weight of an aqueous solution of ammonium persulfate at a concentration of 3% by weight were added dropwise for 4 hours. After completion of the dropwise addition, 10 parts by weight of an aqueous solution of ammonium persulfate at a concentration of 3% by weight was added at once. Thereafter, the temperature was kept at 80 ° C. for 1 hour to complete the polymerization reaction.

After the polymerization was completed, the mixture was cooled to room temperature and neutralized with an aqueous 30% by weight sodium hydroxide solution for about 1 hour. The salt of the water-soluble copolymer prepared as described above showed a weight average molecular weight of 36,500 measured by GPC (Gel Permeation Chromatography) method.

Example 2

283 parts by weight of methoxy polyethylene glycol monomethacrylate (70 moles of an average added mole number of ethylene oxide) as the polymerization composition in Example 1, 41 weight of methoxy polyethylene glycol monomethacrylate (23 moles of an average added mole number of ethylene oxide) Parts, 31.1 parts by weight of methacrylic acid, 3.6 parts by weight of polyoxyethylene nonylphenyl propenyl ether sulfate ammonium salt (10 moles of average added mole number of ethylene oxide) as a nonionic and anionic reactive surfactant, and a mixture of 95 parts by weight of water The same procedure as in Example 1 was carried out except that an aqueous solution was used.

The salt of the prepared water-soluble copolymer exhibited a weight average molecular weight of 39,000 measured by GPC (Gel Permeation Chromatography).

Example 3

285 parts by weight of methoxy polyethylene glycol monomethacrylate (average number of moles of ethylene oxide) as the polymerization composition in Example 1, 37 weight of methoxy polyethylene glycol monomethacrylate (average number of moles of ethylene oxide 23 mol) Parts, 27.9 parts by weight of methacrylic acid, 3.5 parts by weight of polyoxyethylene nonylphenyl propenyl ether sulfate ammonium salt (10 moles of average added mole number of ethylene oxide) as a nonionic and anionic reactive surfactant, a monomer mixed with 95 parts by weight of water The same procedure as in Example 1 was carried out except that an aqueous solution was used.

The salt of the prepared water-soluble copolymer exhibited a weight average molecular weight of 40,500 measured by GPC (Gel Permeation Chromatography).

Example 4

287 parts by weight of methoxy polyethylene glycol monomethacrylate (110 moles of average added mole number of ethylene oxide) as the polymerization composition in Example 1, 33 weight of methoxy polyethylene glycol monomethacrylate (average number of moles of ethylene oxide added 23 moles) Parts, 19.7 parts by weight of methacrylic acid, 3.4 parts by weight of polyoxyethylene nonylphenyl propenyl ether sulfate ammonium salt (10 moles of average added mole number of ethylene oxide) as a nonionic and anionic reactive surfactant, a monomer mixed with 95 parts by weight of water The same procedure as in Example 1 was carried out except that an aqueous solution was used.

The salt of the prepared water-soluble copolymer exhibited a weight average molecular weight of 42,200 measured by GPC (Gel Permeation Chromatography).

Example 5

298.2 parts by weight of methoxy polyethylene glycol monomethacrylate (average added mole number of ethylene oxide) as the polymerization composition in Example 1, 25 weight of methoxy polyethylene glycol monomethacrylate (average added mole number of ethylene oxide 23 mol) Parts, 16.1 parts by weight of methacrylic acid, 3.43 parts by weight of polyoxyethylene nonylphenyl propenyl ether sulfate ammonium salt (10 moles of average added moles of ethylene oxide) as a nonionic and anionic reactive surfactant, and a monomer mixed with 95 parts by weight of water. The same procedure as in Example 1 was carried out except that an aqueous solution was used.

The salt of the prepared water-soluble copolymer exhibited a weight average molecular weight of 43,500 measured by Gel Permeation Chromatography (GPC).

Comparative Example 1

300 parts by weight of methoxy polyethylene glycol monomethacrylate (average added mole number of ethylene oxide) as polymerized composition in Example 1, 49.8 parts by weight of methacrylic acid, polyoxyethylene nonyl as a nonionic and anionic reactive surfactant The same procedure as in Example 1 was conducted except that 3.5 parts by weight of phenyl propenyl ether sulfate ammonium salt (10 moles of average added mole number of ethylene oxide) and 95 parts by weight of water were used.

The salt of the prepared water-soluble copolymer exhibited a weight average molecular weight of 41,100 measured by GPC (Gel Permeation Chromatography) method.

Comparative Example 2

310 weight parts of methoxy polyethylene glycol monomethacrylate (average added mole number of ethylene oxide) as a polymerization composition in Example 1, 45.1 parts by weight of methacrylic acid, polyoxyethylene nonyl as a nonionic and anionic reactive surfactant The same procedure as in Example 1 was carried out except that 3.6 parts by weight of phenyl propenyl ether sulfate ammonium salt (10 moles of average added mole number of ethylene oxide) and 95 parts by weight of water were used.

The salt of the prepared water-soluble copolymer exhibited a weight average molecular weight of 43,300 measured by GPC (Gel Permeation Chromatography) method.

Comparative Example 3

315 parts by weight of methoxy polyethylene glycol monomethacrylate (average added mole number of ethylene oxide) as the polymerization composition in Example 1, 34.9 parts by weight of methacrylic acid, polyoxyethylene nonyl as a nonionic and anionic reactive surfactant The same procedure as in Example 1 was conducted except that 3.5 parts by weight of phenyl propenyl ether sulfate ammonium salt (10 moles of average added mole number of ethylene oxide) and 95 parts by weight of water were used.

The salt of the prepared water-soluble copolymer exhibited a weight average molecular weight of 44,700 measured by GPC (Gel Permeation Chromatography) method.

Comparative Example 4

320 parts by weight of methoxy polyethylene glycol monomethacrylate (110 moles of an average added mole number of ethylene oxide) as the polymerization composition in Example 1, 19.7 parts by weight of methacrylic acid, polyoxyethylene nonyl as a nonionic and anionic reactive surfactant The process was carried out in the same manner as in Example 1, except that 3.4 parts by weight of phenyl propenyl ether sulfate ammonium salt (10 moles of average added mole number of ethylene oxide) and 95 parts by weight of water were used.

The salt of the prepared water-soluble copolymer exhibited a weight average molecular weight of 48,100 measured by GPC (Gel Permeation Chromatography) method.

Comparative Example 5

In Example 1, 323.2 parts by weight of methoxy polyethylene glycol monomethacrylate (average added mole number of ethylene oxide) 323.2 parts by weight, 16.1 parts by weight of methacrylic acid, polyoxyethylene nonyl as a nonionic and anionic reactive surfactant The process was carried out in the same manner as in Example 1, except that 3.43 parts by weight of phenyl propenyl ether sulfate ammonium salt (10 mol of average added moles of ethylene oxide) and 95 parts by weight of water were used.

The salt of the prepared water-soluble copolymer exhibited a weight average molecular weight of 49,200 measured by Gel Permeation Chromatography (GPC).

Comparative Example 6

285 parts by weight of methoxy polyethylene glycol monomethacrylate (average number of moles of ethylene oxide) as a polymerization composition in Example 1, 37.2 parts by weight of methacrylic acid, 19.9 parts by weight of acrylic acid, polyoxyethylene nonyl as a reactive surfactant Phenylpropenyl ether sulfate ammonium salt (average number of moles of ethylene oxide 10 mol) 3.4 parts by weight except that a monomer aqueous solution mixed with 95 parts by weight of water, 5.3 parts by weight of 3-mercapto propionic acid and 60 parts by weight of a mixed solution were used. Was carried out in the same manner as in Example 1.

The salt of the prepared water-soluble copolymer exhibited a weight average molecular weight of 24,000 measured by Gel Permeation Chromatography (GPC).

Comparative example  7

Naphthalene acid formaldehyde condensate (NSF, 40% solids) used as a conventional cement admixture was used.

The main component contents and properties of the water-soluble copolymer salts prepared in Examples 1 to 5 and Comparative Examples 1 to 6 are shown in Table 1 below.

division Polyalkylene glycol (meth) acrylate Polyalkylene glycol (meth) acrylate Carboxylic acid (methacrylic acid / acrylic acid) Reactive surfactant Solid content (% by weight) Weight average molecular weight EO confiscation Content in Copolymer (wt%) EO confiscation Content in Copolymer (wt%) Content in Copolymer (wt%) Content in Copolymer (wt%) Example 1 55 76.4 23 12.7 9.9 1.0 40.1 36,500 Example 2 70 78.9 23 11.4 8.7 1.0 40.1 39,000 Example 3 90 80.6 23 10.5 7.9 1.0 40.2 40,500 Example 4 110 83.7 23 9.6 5.7 1.0 40.2 42,200 Example 5 150 87.0 23 7.3 4.7 1.0 40.1 43,500 Comparative Example 1 55 84.9 - - 14.1 1.0 40.2 41,100 Comparative Example 2 70 86.4 - - 12.6 1.0 40.2 43,300 Comparative Example 3 90 89.1 - - 9.9 1.0 40.0 44,700 Comparative Example 4 110 93.3 - - 5.7 1.0 40.2 48,100 Comparative Example 5 150 94.3 - - 4.7 1.0 40.1 49,200 Comparative Example 6 23 82.5 - - 16.5 1.0 40.1 24,000

[Test Example]

The water-soluble copolymer salts prepared in Examples 1 to 5 and Comparative Examples 1 to 6 and the cement admixture of Comparative Example 7 were tested by the following methods, and the results are shown in Table 2 below.

* Mortar fluidity test-Normally 510 g of Portland cement (manufactured by Ssangyong Shoe), 734 g of sand (standard yarn for compressive strength test), and 0.4 wt% of the cement admixture prepared in Examples and Comparative Examples, respectively, 7 is 0.8% by weight), and 173 g of water (waterworks) were prepared in a mortar mixer according to the KS L 5109 method, which is a mechanical mixing method of hydraulic cement paste and mortar. Each prepared mortar was filled with a hollow cone having a diameter of 60 mm and a height of 40 mm, and then the cone was removed in the vertical direction. The mortar flow value in mm was measured as the mortar diameter in two directions and expressed as an average of the measured diameters.

* Concrete test-Normally, Portland cement 4.3 kg, sand 7.94 kg, crushed stone 9.08 kg, the cement admixtures prepared in Examples and Comparative Examples, respectively, 0.5% by weight of cement (1.0 weight in Comparative Example 7) %), And 1.5 kg of water (waterworks) were kneaded to prepare concrete. After each concrete was measured for slump and air volume, the test agent was added to the mold according to the Korean Industrial Standard KS F 2402 and KS F 2449 method, and stored at a temperature of 20 ° C., and then 16 hours later. The compressive strength (kgf / cm ² ) of the test agent was measured.

division Amount / Cement 100 wt% (wt%) Mortar Flow Value (mm) Concrete Slump (cm) Air volume (%) Compressive strength (㎏f / cm ² ) Mortar admixture Concrete admixture Early 60 minutes Early 60 minutes Early 60 minutes 20 ℃, 16 hours Example 1 0.4 0.5 173 164 22.0 20.0 3.0 2.8 61.5 Example 2 0.4 0.5 173 165 22.0 20.0 2.9 2.8 66.2 Example 3 0.4 0.5 174 165 22.5 20.5 2.9 2.7 89.8 Example 4 0.4 0.5 173 163 22.0 19.5 3.0 2.8 94.9 Example 5 0.4 0.5 172 162 21.5 19.0 3.1 2.8 95.7 Comparative Example 1 0.4 0.5 172 163 21.5 19.5 3.0 2.9 58.6 Comparative Example 2 0.4 0.5 171 163 21.0 19.0 3.2 3.0 62.7 Comparative Example 3 0.4 0.5 172 162 21.5 19.0 3.1 2.9 84.5 Comparative Example 4 0.4 0.5 171 161 21.0 18.5 3.1 2.9 92.1 Comparative Example 5 0.4 0.5 170 158 20.5 18.0 3.2 2.9 93.4 Comparative Example 6 0.4 0.5 165 155 19.5 16.0 3.3 3.2 33.7 Comparative Example 7 0.8 1.0 145 - 15.0 - 3.7 3.4 48.2

As shown in Table 2, the cement admixtures of Examples 1 to 5 prepared by graft copolymerization of alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomers having different average added moles of oxyalkylene groups according to the present invention. The mortar and concrete applied were compared with those of Comparative Examples 1 to 6 prepared by graft copolymerization of any one of the alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomers, and Comparative Example 7, which is a conventional cement admixture. It showed a high mortar flow value, it was found that the concrete slump retention is excellent, and the flowability deterioration of the cement composition was hardly generated over time. In addition, at the curing temperature of 20 ° C., the compressive strength after 16 hours of aging time was relatively high as the weight average molecular weight increased with the increase of the average added mole number of the oxyalkylene group.

Particularly, the fluidity and susceptibility deterioration phenomenon occurs based on Example 3, which indicates that the cement composition has fluidity due to the complex action between the carboxylic acid-based copolymer having a graft structure having a different average added mole number and the cement composition. It is believed to cause excessive viscosity and promote condensation which usually starts after 1 hour.

In addition, in the early strength expression characteristics, Examples 1 to 5 were higher than Comparative Examples 1 to 5, and showed about 2 to 3 times higher strength expression characteristics than the general concrete of Comparative Examples 6 to 7. .

That is, the cement admixture of the present invention improves the dispersibility of the cement particles to increase the holding power, and even if added in a small amount, it can exhibit a high susceptibility, and the strength of the premature strength is reduced by introducing different oxyalkylene groups. At the same time it was confirmed that the excellent retention of fluidity for a certain time.

As described above, according to the present invention, a copolymer having a carboxylic acid monomer as a basic skeleton includes a polyoxyalkylene alkenyl ether sulfate salt as a reactive surfactant as one unit monomer, and an average added mole number of the oxyalkylene group. Cement admixtures prepared by graft copolymerization of different alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomers are prepared by graft copolymerization of alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomers alone. Compared with the conventional cement admixture, it has excellent dispersibility and improves the initial susceptibility, improves the fluidity of the composition even in the region of high susceptibility, improves the cure delay, and expresses the strength early and prevents the fluidity deterioration. High workability due to good workability It has the effect of forming a concrete having a strength.

Claims (13)

a) 50 to 95% by weight of an alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer represented by Formula 1 below, wherein the average added mole number of the oxyalkylene group is an integer of 50 to 200; b) 1 to 20% by weight of an alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer represented by Formula 1 below, wherein the average added mole number of the oxyalkylene group is an integer of 10 to 30; c) 3 to 45 wt% of a (meth) acrylic acid monomer or salt thereof represented by Formula 2; And d) 0.5 to 20% by weight of a polyoxyalkylene alkenylether sulfate salt represented by the following formula (3); A cement admixture comprising at least one member selected from the group consisting of a carboxylic acid-based copolymer polymerized therefrom, and salts thereof; [Formula 1]

In Chemical Formula 1, R ¹ is a hydrogen atom or methyl, R ² O is one or a mixture of two or more oxyalkylenes having 2 to 4 carbon atoms, and in the case of two or more, may be added in a block or random phase, R ³ is alkyl having 1 to 4 carbons, m is the average added mole number of the oxyalkylene group; [Formula 2]

In Chemical Formula 2, R ⁴ is a hydrogen atom or methyl, M ¹ is a hydrogen atom, a monovalent metal, a divalent metal, ammonium, or an organic amine; [Formula 3]

In Chemical Formula 3, R ⁵ is a hydrogen atom or methyl, R ⁶ is alkylene, phenylene or alkylphenylene having 1 to 3 carbon atoms, R ⁷ is one kind or a mixture of two or more kinds of oxyalkylenes having 1 to 4 carbon atoms, and in the case of two or more kinds, R ⁷ may be added in a block or random phase, n is an integer of 10 to 50 as the average added mole number of the oxyalkylene group, M ² is a hydrogen atom, a monovalent metal, ammonium or an organic amine. The method of claim 1, The a) alkoxy polyalkylene glycol mono (meth) acrylic acid ester monomer is methoxy polyethylene glycol mono (meth) acrylate, methoxy polypropylene glycol mono (meth) acrylate, methoxy polybutylene glycol mono (meth) Acrylate, methoxy polyethylene glycol polypropylene glycol mono (meth) acrylate, methoxy polyethylene glycol polybutylene glycol mono (meth) acrylate, methoxy polypropylene glycol polybutylene glycol mono (meth) acrylate, methoxy Polyethylene glycol polypropylene glycol polybutylene glycol mono (meth) acrylate, ethoxy polyethylene glycol mono (meth) acrylate, ethoxy polypropylene glycol mono (meth) acrylate, ethoxy polybutylene glycol mono (meth) acryl Ethylene Polyethylene Glycol Polypropylene Glycol Mono (meth) acrylate It consists of cy polyethyleneglycol polybutylene glycol mono (meth) acrylate, ethoxy polypropylene glycol polybutylene glycol mono (meth) acrylate, and ethoxy polyethylene glycol polypropylene glycol polybutylene glycol mono (meth) acrylate At least one member selected from the group Cement admixture. The method of claim 1, The b) (meth) acrylic acid monomer is at least one member selected from the group consisting of acrylic acid, methacrylic acid, and monovalent metal salts, divalent metal salts, ammonium salts, and organic amine salts of these acids. Cement admixture. The method of claim 1, The c) polyoxyalkylene alkenyl ether sulfate salt is sulfoxy polyethylene glycol nonylphenyl propenyl ether, sulfoxy polyethylene glycol allyl ether, sulfoxy polypropylene glycol allyl ether, sulfoxy polybutylene glycol allyl ether, sulfoxy polyethylene Glycol 2-butenyl ether, sulfoxy polypropylene glycol 2-butenyl ether, sulfoxy polybutylene glycol 2-butenyl ether, sulfoxy polyethylene glycol 3-butenyl ether, sulfoxy polypropylene glycol 3-butenyl ether Sulfoxypoly of sulfoxypolybutylene glycol 3-butenyl ether, sulfoxypolyethylene glycol 3-pentenyl ether, sulfoxy polypropylene glycol 3-pentenyl ether, or sulfoxypolybutylene glycol 3-pentenyl ether Alkylene glycol allyl ethers; Sulfoxypolyethylene glycol (3-vinyl-5-methyl) phenyl ether, sulfoxypolypropylene glycol (3-vinyl-5-methyl) phenyl ether, sulfoxypolybutylene glycol (3-vinyl-5-methyl) phenyl ether , Sulfoxypolyethylene glycol (3-vinyl-5-ethyl) phenyl ether, sulfoxypolypropylene glycol (3-vinyl-5-ethyl) phenyl ether, sulfoxypolybutylene glycol (3-vinyl-5-ethyl) phenyl Ether, sulfoxypolypropylene glycol (3-propenyl-5-propyl) phenyl ether, sulfoxypolybutylene glycol (3-propenyl-5-propyl) phenyl ether, sulfoxypolyethylene glycol (3-propenyl-5 Sulfoxypolyalkylene glycols of -butyl) phenyl ether, sulfoxypolypropylene glycol (3-propenyl-5-butyl) phenyl ether, or sulfoxypolybutylene glycol (3-propenyl-5-butyl) phenyl ether Alkyl vinyl phenyl ethers; 2-sulfoxypolyethylene glycol-3- (4-methylphenoxy) propylene allyl ether, 2-sulfoxy polypropylene glycol-3- (4-methylphenoxy) propylene ether, 2-sulfoxypolybutylene glycol-3 -(4-methylphenoxy) propylene allyl ether, 2-sulfoxypolyethylene glycol-3- (4-ethylphenoxy) propylene allyl ether, 2-sulfoxy polypropylene glycol-3- (4-ethylphenoxy) propylene 2-sulfoxypolyalkylene glycol-3- (4-alkylphenoxy) propylene allyl ethers of allyl ether or 2-sulfoxypolybutylene glycol-3- (4-ethylphenoxy) propylene allyl ether; And At least one selected from the group consisting of monovalent metals, divalent metals, ammonium salts, and salts neutralized with organic amines, respectively. Cement admixture. The method of claim 1, The salt of the carboxylic acid-based copolymer is characterized in that the carboxylic acid-based copolymer further neutralized with an alkaline material Cement admixture. The method of claim 1, The carboxylic acid-based copolymer and salts thereof are characterized in that the weight average molecular weight of 30,000 to 100,000 Cement admixture. a) 50 to 95% by weight of an alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer represented by Formula 1 below, wherein the average added mole number of the oxyalkylene group is an integer of 50 to 200; b) 1 to 20% by weight of an alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer represented by Formula 1 below, wherein the average added mole number of the oxyalkylene group is an integer of 10 to 30; c) 3 to 45 wt% of a (meth) acrylic acid monomer or salt thereof represented by Formula 2; And d) 0.5 to 20% by weight of a polyoxyalkylene alkenylether sulfate salt represented by the following formula (3); Method of producing a cement admixture, characterized in that it comprises the step of copolymerizing under a polymerization initiator; [Formula 1]

In Chemical Formula 1, R ¹ is a hydrogen atom or methyl, R ² O is one or a mixture of two or more oxyalkylenes having 2 to 4 carbon atoms, and in the case of two or more, may be added in a block or random phase, R ³ is alkyl having 1 to 4 carbons, m is the average added mole number of the oxyalkylene group; [Formula 2]

In Chemical Formula 2, R ⁴ is a hydrogen atom or methyl, M ¹ is a hydrogen atom, a monovalent metal, a divalent metal, ammonium, or an organic amine; [Formula 3]

In Chemical Formula 3, R ⁵ is a hydrogen atom or methyl, R ⁶ is alkylene, phenylene or alkylphenylene having 1 to 3 carbon atoms, R ⁷ is one kind or a mixture of two or more kinds of oxyalkylenes having 1 to 4 carbon atoms, and in the case of two or more kinds, R ⁷ may be added in a block or random phase, n is an integer of 10 to 50 as the average added mole number of the oxyalkylene group, M ² is a hydrogen atom, a monovalent metal, ammonium or an organic amine. The method of claim 7, wherein The method of preparing a cement admixture further comprises the step of neutralizing the prepared copolymer with an alkaline material to prepare a copolymer salt. Process for preparing cement admixtures. The method of claim 8, The alkaline substance is a hydroxide, chloride, carbonate, ammonia, or an organic amine of a monovalent or divalent metal. Process for preparing cement admixtures. The method of claim 7, wherein The copolymerization is carried out by a solution polymerization or a bulk polymerization method, characterized in that Process for preparing cement admixtures. The method of claim 7, wherein The copolymerization is carried out at a reaction temperature of 0 to 120 ℃ Process for preparing cement admixtures. The method of claim 7, wherein The copolymerization is carried out by further adding a thiol-based chain transfer agent Process for the preparation of cement admixtures. A cement composition comprising 0.01 to 10 parts by weight of the cement admixture according to claim 1 relative to 100 parts by weight of cement.