WO2018124536A1

WO2018124536A1 - Cement additive composition comprising polycarbonate-based copolymer

Info

Publication number: WO2018124536A1
Application number: PCT/KR2017/014404
Authority: WO
Inventors: 고창범; 류동조; 김임규; 김효민
Original assignee: 주식회사 엘지화학
Priority date: 2016-12-26
Filing date: 2017-12-08
Publication date: 2018-07-05

Abstract

The present invention relates to a cement additive composition comprising a polycarbonate-based copolymer. The cement additive composition of the present invention has an excellent water-reducing performance when used for cement formulation, thereby improving initial dispersibility and improving the fluidity of a composition even in a high sensitivity area of particles, and effectively preventing slump loss of the cement formulation.

Description

[Name of invention]

Cement additive composition comprising a polycarboxylic acid copolymer

[Technical Field]

Cross Citation with Related Application (s)

This application claims the benefit of priority based on Korean Patent Application No. 10-2016-0179503 of December 26, 2016 and Korean Patent Application No. 10-2017—0167553 of December 7, 2017. All content disclosed in the literature is included as part of this specification. The present invention provides a cement additive composition comprising a polycarboxylic acid-based copolymer: It is about.

Background Art

cement. ^Semantic paste prepared by mixing water and other additives ^ᅵ , mor t ar produced by adding sand thereto, cement paste, and gravel, which is coarse aggregate, is added to the mortar Concrete etc. It is used in large quantities in various building materials.

But. Building materials containing cement harden over time due to the hydration reaction between cement and water, resulting in poor workability. In this case, additional water may be added to improve workability, which may lower the compressive strength of the cement building material and cause cracking, so that the total amount of water used is limited to some extent.

In particular, since concrete generally decreases in slump from about 30 minutes after mixing, it is necessary to finish all the work of mixing and pouring concrete in a short time. Various cement additives have been developed to reduce the amount of water used while maintaining the dispersibility of the cement formulation.

Accordingly, various cement dispersants are used to increase the flowability of the cement compound. However, when a highly water-sensitive hydraulic composition is prepared using the cement dispersant, slump loss is remarkable, and workability and workability are deteriorated. there is a problem.

therefore. In the prior art, there is an attempt to use a water-soluble polycarboxylic acid-based co-polymer having a slump-loss prevention property as a cement dispersant for the prevention of slump-loss. Examples of such water-soluble polycarboxylic acid-based copolymers include co-polymers of water-soluble vinyl co-polymer maleic anhydride and alkenyl ether obtained by copolymerizing methacrylate. .

However, in the conventional method using the water-soluble copolymer as a cement dispersant, there is a problem that the slump loss preventing effect is not sufficient, the effect changes with time, and decreases.

Therefore, there is a need for a technology that can solve these problems.

[Detailed Description of the Invention]

[Technical problem]

The present land-based cement additive composition comprising a polycarboxylic acid-based copolymer capable of effectively preventing slump loss as well as increasing initial dispersibility due to excellent water sensitization performance without adding a separate water reducing agent or slump retention agent. To provide.

Technical Solution

The present invention,

An alkoxy polyalkylene glycol (meth) acrylic acid ester repeating unit, a polyalkylene glycol ether repeating unit, and a (meth) acrylic acid repeating unit; Crosslinked by an ethylene glycol di (meth) acrylate-based crosslinking agent; Provided is a cement additive composition comprising a polycarboxylic acid-based copolymer.

【Effects of the Invention】

When the cement additive composition of the present invention is used in cement blending, it has excellent water-resistance performance to increase initial dispersibility, improves the fluidity of the composition even in the region of high susceptibility of particles, and effectively prevents slump loss of the cement blend. can do. [Form for implementation of invention]

The terminology used herein is for the purpose of describing exemplary embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. As used herein, the terms "comprise", "comprise" or "have" are intended to indicate that the features, numbers, steps, components, or combinations thereof are present, one or more other features It is to be understood that the present invention does not exclude the possibility of adding or presenting numbers, steps, components, or combinations thereof.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated and described in detail below. However, this is not intended to limit the present invention to a specific disclosed form, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. Hereinafter, the cement additive composition of this invention is demonstrated in detail.

Cement additive composition according to an aspect of the present invention, alkoxypolyalkylene glycol (meth) acrylic acid ester repeating unit, polyalkylene glycol ether repeating unit, (meth) acrylic acid repeating unit; Crosslinked with an ethylene glycol di (meth) acrylate-based crosslinker; Polycarboxylic acid-based copolymers.

The polycarboxylic acid-based co-polymer contained in the cement additive composition of the present invention includes each repeating unit as described above. Crosslinking is formed by ethylene glycol di (meth) acrylate-based crosslinking agent in each repeating unit, providing superior dispersibility than conventional cement additives, and improving the flowability of the cement compound even in the region of high susceptibility. It is possible to prevent the long-term deterioration of the improved flowability for a long time, thereby imparting good workability to the cement compound.

According to one embodiment of the invention, the alkoxypolyalkylene glycol (meth) acrylic acid ester-based repeating unit may be derived from a monomer represented by the following formula ^' 1. [Formula 1]

In Chemical Formula 1,

R1 is hydrogen or alkyl having 1 to 3 carbon atoms,

R11 to R14 are each independently the same or different and have 1 to

Alkylene of 4,

nil to m4 are the additional moles of alkylene oxide repeat units, each independently, identically or identically, an integer from 0 to 200, ml + m2 + iii3 + ni4 is 50 to 200,

By the alkylene oxide one kind or a mixture of two or more kinds, it is possible to form a random or block phase,

R15 is hydrogen or an alkyl group having 1 to 4 carbon atoms.

Since the alkoxypolyalkylene glycol (meth) acrylic acid ester monomer of this type contains a unsaturated double bond which can participate in a radical reaction, it can be copolymerized with other monomers and induces electrostatic repulsion between dispersed particles. It is possible to improve the dispersibility and stability of the particles. Also, because of this principle. It can maintain slump fluidity for a long time. It is possible to prevent the change of the cement compound over time.

In particular, in the case where the added mole number of the alkylene oxide repeating units represented by ιτύ to m4 is about 50 to about 200, dispersibility and slump retention can be further improved, and such repeating unit addition mole number is preferably about 50 to about 150.

Specifically, the monomer represented by the formula (1) is, for example, methoxy polyethylene glycol (meth) acrylate oxypolypropylene glycol (meth) acrylate, hydroxypolybutylene glycol (meth) acrylate. Mexy polyethyleneglycol polypropylene glycol. (Meth) acrylate, Methoxypolyethylene glycol Polybutylene glycol (meth) acrylate, Methoxy polypropylene glycol Polybutylene glycol (meth) acrylate, Mexy polyethylene glycol Polypropylene glycol Polybutylene glycol (meth) acrylate, Especial polyethylene Glycol (meth) acrylate, Ethoxy Polypropylene Glycol

(Meth) acrylate Especial polybutylene glycol (meth) acrylate, ethoxy polyethylene glycol polypropylene glycol (meth) acrylate, ethoxy polyethylene glycol polybutylene glycol (meth) acrylate, especial polypropylene glycol full Butylene glycol (meth) acrylate, an ethoxy polyethylene glycol polypropylene glycol polybutylene glycol (meth) acrylate, etc. are mentioned, It can use individually or in mixture of 1 or more types. And, the polyalkylene glycol ether-based repeating unit is represented by the following formula (2)

In Chemical Formula 2,

R2 is hydrogen or alkyl having 1 to 3 carbon atoms,

R21 to R24 are each independently, identically or differently, alkylene having 1 to 4 carbon atoms,

nl to n4 are the additional moles of alkylene oxide repeat units, each independently, identically or differently, an integer from 0 to 200, nl + n2 + n3 + n4 is 50 to 200,

By the mixed composition of one or two or more of the alkylene oxides, it is possible to form a random or block phase,

R25 is hydrogen or an alkyl group having 1 to 4 carbon atoms.

This type of polyalkylene glycol ether monomer also contains unsaturated double bonds that can participate in radical reactions. With other monomers Copolymerization is possible, and by adjusting the degree of polarity that may partially occur in the entire polycarboxylic acid copolymer, the adsorption rate and the degree of adsorption of cement particles can be efficiently increased. The initial fluidity can be improved when cement is blended. Specific examples of the monomer represented by the above formula (2) include, for example, mesospecific polyethylene glycol (meth) allyl ether, ethoxy polyethylene glycol

(Meth) allyl ether, propoxy polyethylene glycol (meth) allyl ether, annex polyethylene glycol (meth) allyl ether, phenoxy polyethylene glycol

(Meth) allyl ether, polyethyleneglycol vinyl ether, polyethyleneglycol monoallyl ether, polyethyleneglycol (meth) allyl ether, etc. are mentioned, It can use individually or in mixture of 1 or more types.

According to one embodiment of the invention. The polyalkylene glycol ether-based repeating unit is about 50 to about 150 parts by weight, preferably about 70 to about 120 parts by weight, based on 100 parts by weight of the alkoxypolyalkylene glycol (meth) acrylic acid ester-based repeating unit. Can be used.

When the polyalkylene glycol ether repeating unit is relatively contained, the slump loss occurs quickly, the problem that the fluidity may be lowered. The problem of poor dispersion may occur. In addition, the polycarboxylic acid-based co-polymer included in the cement additive composition according to an aspect of the present invention includes a (meth) acrylic acid-based repeating unit.

The (meth) acrylic acid-based repeating unit may be a cap derived from a monomer represented by the following formula (3).

[Formula 3]

In Chemical Formula 3 above.

R3 is hydrogen or alkyl having 1 to 3 carbons. R31 is hydrogen, monovalent or divalent metal silver, ammonium ion, or primary to quaternary ammonium ion.

The (meth) acrylic acid-based repeating unit can realize an effect of improving the initial dispersibility of the cement composition by increasing a functional group which can adsorb to the semantic particles in the polycarboxylic acid-based copolymer. Specifically, the monomer represented by Formula 3 may be, for example, at least one selected from the group consisting of acrylic acid, methacrylic acid, metal salts of these acids, ammonium salts, and organic amine salts.

According to one embodiment of the invention. These (meth) acrylic acid repeating units, the above-described alkoxy polyalkylene glycol (meth) acrylate-based repeating unit ⁱ

About 100 to about 50 parts by weight, preferably about 20 to about 50 parts by weight

40 parts by weight can be used.

Relatively less (meth) acrylic acid type repeating units are included. In this case, a problem may occur that the initial dispersing force is lowered, and when a relatively large number of (meth) acrylic acid repeating units are included, the initial dispersibility may be increased while a slump loss may occur quickly. And, in the polycarboxylic acid-based copolymer contained in the cement additive composition according to an aspect of the present invention. Each repeating unit mentioned above exists in the state which formed the crosslinked bond with the ethylene glycol di (meth) acrylate type crosslinking agent.

By such crosslinking, the polycarboxylic acid-based copolymer increases the adsorption rate to the cement particles, thereby inducing the interparticle dispersion due to steric repulsion, thereby improving the initial water-resistance and retention in the cement compound, and excellent work for a long time. The effect of giving sex can be realized.

Ethylene glycol di (meth) acrylate type crosslinking agent is specifically, for example. Polyethyleneglycol diacrylate (PEGDA), Polypropyleneglycol diacrylate (PPGDA), nucleic acid diethoxylated arte diacrylate (l, 6-Hexane Neopenty 1 eneg lycolet hoxy late diacrylate, neopentylene glycol propoxylate diacrylate (1,6— Hexanediolpropoxylate diacrylate), neopentylene glycol propoxylate diacrylate (Neopenty leneglycolpropoxy late) diacrylate), Trimethylpropaneethoxylate tr iacrylate, Trimethylpropanepropoxylate triacrylate, Pentaerythrethicate triacrylate (Pentaerythr i tolethoxyl ate tr) iacrylate), or pentaerythritol propoxylate triacrylate, and the like, and may be used alone or in combination of two or more thereof.

According to one embodiment of the invention, the crosslinking agent component is about 0.01 to about 0.5 parts by weight, preferably about 0.05 to about 0.3 parts by weight based on 100 parts by weight of the alkoxypolyalkylene glycol (meth) acrylic acid ester repeating unit described above. It can be used in parts by weight.

When the amount of the crosslinker component is relatively low, problems of initial dispersing force and compressive strength may occur. In the case where a relatively large amount is included, workability may be deteriorated due to a decrease in initial dispersion performance. On the other hand, the polycarboxylic acid-based copolymer contained in the semantic additive composition according to an embodiment of the present invention is an alkoxypolyalkylene glycol (meth) acrylic acid ester repeating unit, polyalkylene glycol ether repeating unit. A (meth) acrylic acid repeating unit must be included at the same time, and a crosslinking bond must be formed by an ethylene glycol di (meth) acrylate crosslinking agent. By this combination, slump loss can be effectively prevented when the cement additive composition is added to the cement and blended, and at the same time, even after a certain time after the blending. It is possible to maintain excellent compressive strength.

In particular, even if the repeating unit resulting from any one of the repeating units lacks or includes all of the repeating units, In the case of the lack of crosslinking, problems due to slump loss and a problem of greatly lowering the compressive strength may occur. The polycarboxylic acid-based copolymer may be added as it is to be used as a cement blending component, and if necessary, may be reacted with a basic substance, added in the form of a salt, and used as a cement blending component.

For example, the basic material may include hydroxides, chlorides, carbonates of monovalent or divalent metals, ammonia, or primary to tertiary amines. By using the polycarboxylic acid-based copolymer in the form of a salt, it is possible to obtain a slump holding force and an appropriate air entraining effect of the cement composition, which is in the form of about 10 to about 50% by weight of the total polycarboxylic acid-based copolymer It is preferable to include. The polycarboxylic acid copolymer used in the cement additive composition according to an aspect of the present invention may be prepared by a method of co-polymerizing using a polymerization initiator in a state containing each monomer component described above. As the co-polymerization method, a polymerization method generally used in the technical field to which the present invention belongs, such as solution polymerization or ghosting polymerization, can be used without particular limitation.

For example, in the case of polymerization using water as a solvent, the solution polymerization initiator used may be a water-soluble polymerization initiator of ammonium or alkali metal persulfate or hydrogen peroxide, and may be used in lower alcohol, aromatic hydrocarbon, aliphatic hydrocarbon, S. Polymerization using a tere compound or a ketone compound as a solvent includes peroxides such as benzoyl peroxide, lauryl peroxide and cumene hydroperoxide; Aromatic azo compounds, such as azobis isobutyronitrile, etc. can be used. In addition, at this time, accelerators, such as an amine compound, can also be used together at this time.

And when using the mixed solvent of water and a lower alcohol, it can select suitably from the said various polymerization initiator or the combination of a polymerization initiator, and an accelerator, and can use.

A suitable amount of the polymerization initiator may be 0.5 to 5 parts by weight based on 100 parts by weight of the total monomers, and the polymerization temperature depends on the type of solvent or polymerization initiator used. So it may vary, for example. It can be selected from the range of about 0 ^° C to about 120 ^° C.

In addition, a thi-type chain transfer agent can also be used together for the molecular weight control of the obtained polycarboxylic-acid copolymer.

The thiol-based chain transfer agent used in this case is mercapto ethanol, thioglycerol, thioglycolic acid, 2-mercapto propinic acid, 3-mercapto propionic acid, thiosapic acid, thioglycolic acid octyl, 3-mercapto propionic acid octyl It may be one or more selected from.

The amount of the thiol-based chain transfer agent used may be, for example, about 0.01 to about 5 parts by weight based on 100 parts by weight of the total monomers described above.

According to one embodiment of the invention, the polycarboxylic acid-based co-polymer and the neutralized copolymer salt has a weight average molecular weight of about 30, 000 to about 50, 000 g / as measured by GPCCGel Permeat i on Chromatography mol, or about 33, 000 to about 40, 000 g / mol, or about 35, 000 to about 38, 000 g / mol, may be desirable in view of dispersibility when combined with cement. Such semantic additive composition may be from about 0.01 to about 10 parts by weight, and preferably from about 0.05 to about 5 parts by weight, or about 0.1 part by weight, based on 100 parts by weight of the total of the semantic formulation when cement is blended. To about 5 parts by weight.

When the content of the semantic additive composition is too low with respect to the whole cement compound, it may be difficult to achieve performances such as slump retention, susceptibility, and air entrainment. The content of the cement additive composition is too high with respect to the entire semantic compound. In this case, the economy is inferior. Hereinafter, the operation and effects of the invention will be described in more detail with reference to specific examples of the invention. However, such embodiments are only to be presented as an example of the invention, whereby the scope of the invention is not defined.

Example 1 Polycarboxylic Acid Copolymerization 200 parts by weight of water was injected into a 2 L glass reactor equipped with a thermometer, a stirrer, a dropping funnel, a nitrogen inlet tube, and a reflux condenser, and the inside of the reaction vessel was replaced with nitrogen and heated to 70 ^° C. under a nitrogen atmosphere under stirring.

20 parts by weight of an aqueous solution of ammonium persulfate at a concentration of 3% by weight was added to the reactor, followed by complete dissolution.

i) methoxy polyethylene glycol methacrylic acid ester monomer; (Additional mole number of ethylene oxide repeat units: 50)

i i) methoxy polyethylene glycol metlyl ether; (Additional mole number of ethylene oxide repeat units: 50)

i i i) acrylic acid;

iv) polyethylene glycol diacrylate crosslinkers; And (addition mole number of ethylene oxide repeat units: 10)

The aqueous monomer solution ^mixed with 90 parts by weight of water

A mixed solution of 3.0 parts by weight of 2-mercapto ethane and 30 parts by weight of water;

And. 70 parts by weight of an aqueous ammonium persulfate solution at a concentration of 3% by weight is mixed,

It was dripped for 4 hours.

End of dropping: After the addition of aqueous solution of ammonium persulfate at concentration of 3 weight ¾ again. 10 parts by weight were added at a time.

Thereafter, the temperature was maintained at 70 ^° C. for 1 hour to complete the polymerization reaction. After the polymerization was completed, the mixture was cooled to room temperature, and then neutralized with 30% by weight aqueous sodium hydroxide solution for about 1 hour to prepare a solid 50%.

The salt of the obtained water-soluble copolymer was found to have a weight average molecular weight of 38, 000 when measured by GPC (Gel Permeat i on Chromatography). Examples 2 to 5 and Comparative Examples 1 to 5: The same procedure as in Example 1 was conducted except that the polycarboxylic acid copolymer polymerization composition was changed. The composition and weight average molecular weight values are summarized in Table 1 below.

Table 11 Alkoxypolyalkyl

(Meth) extended lenglycol polyalkylenegly

Acrylic average (meth) acrylic acid collether crosslinking agent

Acid-based molecular weight ester monomer

Monomer

E0 content E0 content content E0

content

Addition (extended part added (extended part (extended part added (g / mol))

(Part by weight) moles) moles)) moles

practice

50 200 50 200 60 10 0.125 38.000 Example 1

practice

50 200 50 200 60 10 0.25 37,000 Example 2

practice

100 200 100 200 60 10 0.5 35,000 Example 3

practice

50 200 50 300 60 10 0.25 37.500 Example 4

practice

50 200 50 100 60 10 0.25 36,000 Example 5

compare

50 400-ᅳ 60 ᅳ-29,000 Example 1

compare

--50 400 60. 28,000 Example 2

compare

50 200 50 200 60--28,500 Example 3

compare

50 200 50 200 30 29,000 Example 4

compare

50 400--46.8 10 0.32 29,500 Example 5 Experimental Example

Usually, 7.5 kg of Portland cement (Ssangyong Shoe), 16.5 kg of sand, 19.0 kg of gravel, and the polycarboxylic acid-based copolymers prepared in the examples and comparative examples (0.2 wt% of cement weight and 3.0 kg of water (water supply) are blended. To prepare concrete.

Each concrete produced was measured for slump by the Korean Industrial Standard KS F 2402, and the compressive strength was measured according to the Korean Industrial Standard KS F 2405. The results are summarized in Table 2 below.

[Table 2]

Referring to Table 2 above, according to an embodiment of the present invention. Cement additives

It can be clearly confirmed that the ¾ property can effectively prevent the initial slump loss compared to the comparative example when added to the cement. Specifically, for the comparative example. Immediately after blending and after 60 minutes of blending, the slump value is largely about 10%. Almost no difference in slump value immediately after blending and 60 minutes after blending You can clearly see that.

In addition, also in the compressive strength, according to the embodiment of the present invention, it can be seen that after 7 days of blending, the compressive strength value is significantly higher than that of the comparative example, compared to after 3 days of blending, and specifically, about m high compressive strength value. It can be clearly seen that

On the other hand, when the comparison unit which lacks the repeating unit originating from a specific monomer, and the crosslinking agent is not used, and 2, it is confirmed that slump loss is severe and compressive strength fell large. In addition, referring to Comparative Examples 3 to 5, even when the crosslinking agent was used, the repeating unit resulting from the specific monomer was lacking. Even if all monomers were included, no crosslinking was formed by the crosslinking agent. It can be clearly seen that the compressive strength is greatly reduced. And in all the said comparative examples, the weight average molecular weight value of a polycarboxylic acid type copolymer is It can be confirmed that all of the ^' less than about 30, 000, these results, it is considered that the change in the endogenous structure of the polycarboxylic acid-based co-polymer of cement additives. example. When cement is added by adding a cement additive composition according to one embodiment of the invention. It is excellent in processability, high compressive strength after curing, and is expected to be applicable to various applications such as buildings.

Claims

[Range of request]

[Claim 11

An alkoxy polyalkylene glycol (meth) acrylic acid ester repeating unit, a polyalkylene glycol ether repeating unit, a (meth) acrylic acid repeating unit; Crosslinked with an ethylene glycol di (meth) acrylate-based crosslinker; A semantic additive composition comprising a polycarboxylic acid copolymer.

[Claim 2]

The method of claim 1,

The alkoxypolyalkylene glycol (meth) acrylic acid ester-based repeating unit is derived from a monomer represented by the following formula (1), a semantic additive composition:

[Chemical Machining 1]

In Chemical Formula 1,

R1 is hydrogen or alkyl having 1 to 3 carbon atoms,

R11 to R14 are each independently, identically or differently, alkylene having 1 to 4 carbon atoms,

ml to m4 are the added moles of alkylene oxide repeat units, each independently. Identically or differently, an integer from 0 to 200, ηύ + ιιι2 + ηι3½4 is 50 to 200,

R15 is hydrogen or an alkyl group having 1 to 4 carbon atoms. [Claim port]

3.】

According to claim 12 The monomer represented by the formula (1) is methoxy polyethylene glycol (meth) acrylate, special polypropylene glycol (meth) acrylate methoxy polybutylene glycol (meth) acrylate methoxy polymethyl glycol polypropylene glycol (meth) acrylic Methoxypolyethylene glycol Polybutylene glycol (meth) acrylate Methoxy polypropylene glycol Polybutylene glycol (meth) acrylate Methoxypolyethylene glycol Polypropylene glycol Polybutylene glycol (meth) acrylate Ethoxy polyethylene glycol (meth Acrylate, Ethoxy Polypropylene Glycol

(Meth) acrylate, especial polybutylene glycol (meth) acrylate, especial polyethylene glycol polypropylene glycol (meth) acrylate. Ethoxy Polyethylene Glycol Polybutylene Glycol (meth) acrylate, Ethoxy Polypropylene Glycol Polybutylene Glycol (meth) acrylate and Especial Polyethylene Glycol Polypropylene Glycol Polybutylene Glycol

At least one member selected from the group consisting of (meth) acrylates. Cement additive composition.

[Claim 4]

The cement additive composition according to claim 1, wherein the polyalkylene glycol ether-based repeating unit is derived from a monomer represented by the following general formula (2):

[Formula 2]

In Chemical Formula 2,

R2 is hydrogen or alkyl having 1 to 3 carbon atoms,

nl to n4 are the additional moles of alkylene oxide repeat units, each independently, identically or differently, an integer from 0 to 200, and nl + n2 + n3 + n4 is 50 To 200,

R25 is hydrogen or an alkyl group having 1 to 4 carbon atoms.

[Claim 5]

The method of claim 4,

The monomer represented by the formula (2) is mesooxy polyethylene glycol (meth) allyl ether, ethoxy polyethylene glycol (meth) allyl ether, propoxy polyethylene glycol (meth) allyl ether, butoxy polyethylene glycol

^■ a (meth) allyl ether, phenoxy polyethylene glycol (meth) allyl ether, polyethylene glycol vinyl ether. Polyethylene glycol monoallyl ether, and polyethylene glycol (meth) at least one member, simaen agent additive composition is selected from ^'the group consisting of allyl ethers.

[Claim 6

The method of claim 1,

The (meth) acrylic acid-based repeating unit is derived from a monomer represented by the following formula (3), cement additive composition:

[Formula 3]

In Chemical Formula 3,

R3 is hydrogen or alkyl having 1 to 3 carbons

R31 is hydrogen, monovalent or divalent metal ion, ammonium silver. Or primary to quaternary ammonium ions.

[Claim 7] The method of claim 6.

The monomer represented by the formula (3) is at least one member selected from the group consisting of acrylic acid, methacrylic acid, metal salts of these acids, ammonium salts, and organic amine salts, cement additive composition.

[Claim 8]

In that U term.

The ethylene glycol di (meth) acrylate crosslinking agent,

Polyethyleneglycol diacrylate (PEGDA), Polypropyleneglycol diacrylate (PPGDA), Nucleic acid diol acrylate diacrylate (1,6-Hexanediolethoxylate diacrylate) (1.6 ᅳ

Hexanediolpropoxylate diacrylate, neopentyleneglycol "Nepentyleneglycolethoxylate diacrylate", Neopentyleneglycolpropoxylate diacrylate, .Trimethylpropaneethoxylate triacrylate. tr i aery late), trimethyl propane propoxylate triacrylate, pentaerythritolethoxy te triacrylate, and pentaerythritol propoxyl Cement additive composition, which is at least one selected from the group consisting of latent triacrylate (Pentaerythr i tolpropoxylate triacrylate).

[Claim 9]

The method of claim 1.

The copolymer,

Per 100 weight part of alkoxy polyalkylene glycol (meth) acrylic acid ester system repeating units;

50 to 150 parts by weight of a polyalkylene glycol ether repeating unit;

10 to 50 parts by weight of (meth) acrylic acid-based repeating units; And Cement additive composition comprising 0.05 to 0.5 parts by weight of ethylene glycol di (meth) acrylate-based crosslinking agent.

[Claim 10]

The method of claim 1,

The polycarboxylic acid-based co-polymer;

Cement additive composition comprising any one or more of the metal salt of the polycarboxylic acid-based copolymer and the ammonium salt of the polycarboxylic acid-based copolymer. [Claim 11]

The method of claim 1,

The weight average molecular weight of the polycarbon-based copolymer is 30.000 to 70, 000 g / iK) l, cement additive composition.