KR101707572B1 - Cement admixture and concrete composition containing the same - Google Patents

Abstract

The present invention relates to a cement admixture comprising an unsaturated vinyl amine-based monomer, an oxy alkylene-based monomer and a carboxylic acid-based copolymer polymerized from a carboxylic acid-based monomer. According to the present invention, provided are a cement admixture preventing degradation of flowability and applying excellent workability to a cement composition, and a concrete composition comprising the same.

Description

TECHNICAL FIELD The present invention relates to a cement admixture and a concrete composition containing the cement admixture.

The present invention relates to a cement admixture, and more particularly, to a cement admixture which improves the initial watering rate and the fluidity of the composition even in a high water reducing rate, A cement admixture and a concrete composition containing the same.

Cement admixture has been widely used as a water-reducing agent in cement compositions such as cement paste, mortar and concrete. This is indispensable in constructing civil engineering and building structures from the present cement compositions. Such a concrete admixture increases the fluidity of the cement composition to reduce the water requirement of the cement composition, and is effective in improving the strength, durability and the like of the hardened product. Among these water reducing agents, the polycarboxylic acid concrete admixture containing the polycarboxylic acid polymer exhibits a superior water-reducing ability to naphthalene and other conventional water reducing agents, and therefore, in many cases, it has already been found that air-entraining and high- (high-range) water-reducing admixture.

The admixture for concrete can be largely divided into lignin type, naphthalene type, and polycarboxylic acid type, and the polycarboxylic acid type admixture is growing rapidly as high strength concrete is required in the building structure. The polycarboxylic acid-based admixture can be classified into an ester group and an ether group according to the chemical structure, and in the case of the ether polycarboxylic acid admixture, the production process is simple and the use amount thereof is increasing.

The polycarboxylic acid-based admixture has an advantage of being able to obtain very excellent fluidity and retention even by adding a small amount of the admixture, but has a problem that the hardening delay is large. Accordingly, it is possible to provide a cement admixture which can improve the workability and shorten the construction period by manifesting early strength by shortening the setting time and exhibiting high sensitivity and sufficient fluidity by improving the problem of the hardening delay of the polycarboxylic acid- Has been developed.

Particularly, a water-soluble vinyl copolymer high performance AE water reducing agent having excellent dispersion characteristics using the steric repulsion of an oxyalkylene group and shortening the setting time has 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.

However, in order to shorten the setting time, the number of moles of the oxyalkylene group added is too high and the initial sensitivity is excellent, but the slump retention of the cement composition is rapidly deteriorated To maintain sufficient dispersibility, a large amount of additive is required. Therefore, improvement of the hardening time delay is required to improve the workability at an early stage while satisfying the excellent slump retention force.

Japanese Laid-Open Patent Publication No. 2006-552416 (December 15, 2006)

The present invention can reduce the amount of water to be mixed with concrete even when a smaller amount than the conventional cement admixture is used, improve the initial susceptibility and improve the fluidity of the composition even in a high water reducing rate region, A cement admixture for imparting good workability and a concrete composition containing the same.

In the present specification, an unsaturated vinylamine-based monomer; Oxyalkylene monomers; And a carboxylic acid-based copolymer polymerized from a carboxylic acid-based monomer.

Also, in this specification, there is provided a concrete composition comprising the cement admixture.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A concrete admixture according to a concrete embodiment of the present invention and a concrete composition containing the same will be described in detail below.

According to one embodiment of the present invention, there can be provided a cement admixture comprising an unsaturated vinylamine monomer, an oxyalkylene monomer, and a carboxylic acid polymer polymerized from a carboxylic acid monomer.

Hereinafter, the present invention will be described in detail.

The present inventors have found that the cement admixture prepared by adding the unsaturated vinylamine monomer, the condensed monomer of the unsaturated vinylamine monomer and the oxyalkylene monomer, and the carboxylic acid monomer is superior to the conventional cement admixture in dispersibility and initial fluidity And by significantly improving the hardening delay, it is confirmed that the fluidity is prevented from deteriorating and excellent workability is imparted, and the present invention has been accomplished based on this finding.

The unsaturated vinylamine-based monomer may include a compound represented by the following formula (1), an isomer thereof, or a mixture thereof.

 [Chemical Formula 1]

R 1, R 2 and R 3 may be the same or different from each other and are each hydrogen or a methyl group,

X 'is an alkyl group having 1 to 5 carbon atoms.

The condensation monomer of the unsaturated vinylamine-based monomer and the oxyalkylene-based monomer may include a compound represented by the following formula (2), an isomer thereof, or a mixture thereof.

(2)

In the general formula (2), R1, R2 and R3 may be the same or different from each other and are each hydrogen or a methyl group, R4 and R5 may be the same or different and each is hydrogen, an alcohol or a saccharide having 3 to 6 carbon atoms, and X ' An alkyl group having 1 to 5 carbon atoms,

R ^X may be the same as or different from X ', and each represents an alkylene group having 2 to 18 carbon atoms,

m and n are an average number of moles of oxyalkylene groups, and are an integer of 1 to 50, and may be the same or different from each other.

The condensation monomer represented by Formula 2 may be any one of poly (meth) aryl ether of a glycerin-ethylene oxide adduct and polyallylamine monomer of a glucose-ethylene oxide adduct.

The cement admixture may further comprise a compound represented by the following formula (3), an isomer thereof, or a mixture thereof.

(3)

In Formula 3, X and Y may be the same or different from each other, and hydrogen, a methyl group, -COOM ₃ , and X or Y may form an anhydride ring with -COOM ₂ ,

Z is hydrogen, a methyl group or -CH ₂ COOM ₃ ,

M ₂ and M ₃ may be the same or different from each other and are each hydrogen, an alkali metal, ammonium (-NH ₄ ), an organic amine,

R1, R2 and R3 may be the same or different and are each hydrogen or a methyl group,

R ^X is an alkylene group having 2 to 4 carbon atoms,

R4 and R5 may be the same or different and each is hydrogen, an alcohol or a saccharide having 3 to 6 carbon atoms,

m and n are an average number of moles of oxyalkylene groups, and are integers of 1 to 50,

X 'is an alkyl group having 1 to 5 carbon atoms,

a and b are integers of 1 to 20, and k is an integer of 1 to 7.

The cement admixture of the present invention is a copolymer polymerized from 20 to 80% by weight of the monomer represented by the formula (1), 20 to 80% by weight of the condensation monomer represented by the formula (2).

The polycarboxylic acid polymer composition of the present invention is a polycarboxylic acid-based copolymer polymerized from an unsaturated vinylamine monomer, a condensation monomer of the unsaturated vinylamine monomer and an oxyalkylene monomer, and a carboxylic acid monomer.

The unsaturated vinylamine-based monomer represented by the above-mentioned formula (1) may be an allyl amine, a but-3-enyl amine, a pent-4-enyl amine, Hexyl-5-enyl amine, methyl allyl amine, ethyl allyl amine, 2-methyl-2-propyl- (2-ethyl-2-propen-1-amine) and the like may be selected. These may be used alone or in combination of two or more kinds thereof. .

The monomer represented by the formula (1) is preferably contained in an amount of 20 to 80% by weight based on the total weight of the cement admixture. When the content is 20 to 80% by weight, the fluidity is excellent.

The compound represented by the general formula (2) can be formed by a condensation reaction of an unsaturated vinylamine-based monomer and an oxyalkylene-based monomer. Specifically, the condensation monomer represented by the above formula (2) may be any one of poly (meth) aryl ether of a glycerin-ethylene oxide adduct and polyallyl amine monomer of a glucose-ethylene oxide adduct .

In the present invention, due to the bulky polyalkylene glycol chain structure of the compound represented by the general formula (2), an excellent dispersing property is exhibited. Specifically, the content of the formula (2) is preferably 20 to 80% by weight based on the cement admixture. When the content is 20 to 80% by weight, the dispersion performance of the cement composition Is improved.

The compound represented by the general formula (3) can be formed by copolymerization of the carboxylic acid monomer and the condensation monomer represented by the general formula (2).

The carboxylic acid monomers may be selected from acrylic acid, methacrylic acid, maleic acid, maleic anhydride, crotonic acid, citraconic acid, citraconic anhydride, itaconic acid, itaconic anhydride and fumaric acid, Can be mixed and copolymerized.

Further, the amide bond contained in the unsaturated vinylamine monomer represented by the general formula (3) can maintain a strong bonding force even in an alkaline atmosphere, thereby preventing the deterioration of fluidity.

The weight average molecular weight of the carboxylic acid copolymer according to the present invention is preferably 20,000 to 50,000. When the weight average molecular weight is 20,000 to 50,000, the initial dispersibility is improved, the initial water retention is improved, the slump retention of the composition is maintained, the fluidity is prevented from lowering, and a concrete composition having high strength can be formed have.

The concrete composition of the present invention includes cement and the above-described cement admixture.

The cement admixture is preferably contained in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the cement.

The cement admixture according to the present invention is superior to the conventional cement admixtures in terms of initial dispersibility and thus improves the initial yield and improves the fluidity of the composition even in the region of high water retention, A cement admixture and a concrete composition containing the same.

The invention will be described in more detail in the following examples. However, the following examples are illustrative of the present invention, and the present invention is not limited by the following examples.

Manufacturing example  One: Poly Alkylene glycol Vinyl more ( Poly alkyleneglycol 비닐 ) Produce

< Synthetic example : Ally Amine  Ethylene Oxide  Monomer production>

A high-pressure reactor equipped with a thermometer, a stirrer, and an ethylene oxide injection device was prepared. 580 parts by weight of allyl amine was added to the reactor, the inside of the reactor was replaced with nitrogen five times while stirring, and the temperature was raised to 60 ° C.

Thereafter, 880 parts by weight (20 parts by mol of ethylene oxide added) of ethylene oxide was added slowly for 2 hours. After all the ethylene oxide was injected, the unreacted ethylene oxide was reacted for 1 hour until the residual ethylene oxide content became 5 ppm or less to prepare an allylamine ethylene oxide monomer.

The final molecular weight of the obtained ethylene oxide monomer of allylamine was about 146, and an unsaturation degree of 99.8% and a total amine value of 384 KOH / g were obtained.

Example  One

243 parts by weight of the allylamine ethylene oxide monomer obtained in the above Synthesis Example and 0.12 part by weight of potassium hydroxide (KOH) (95% Flake) were charged and the inside of the reactor was replaced with nitrogen five times while stirring, and then the temperature was raised to 150 ° C.

Thereafter, 757 parts by weight (ethylene oxide addition mole number: 17.2 mol) of ethylene oxide was gradually added. After all the ethylene oxide was injected, the unreacted ethylene oxide was completely reacted for 1 hour until the residual ethylene oxide content became 5 ppm or less.

After completion of the reaction, the temperature was lowered to 70 ° C or lower and 0.15 part by weight of acetic acid was added to neutralize the catalyst in the system to obtain a polymer of allylamine ethylene oxide monomer and ethylene oxide monomer.

The final molecular weight of the polymer was about 600, the ethylene oxide addition reaction time was 5 hours, the degree of unsaturation was 99.5%, and free-PEG was 0.5%.

Example  2

146 parts by weight of the allylamine ethylene oxide monomer obtained in the above Synthesis Example and 0.2 part by weight of potassium hydroxide (KOH) (95% Flake) were charged and the inside of the reactor was replaced with nitrogen five times with stirring, and then the reaction temperature was raised to 150 ° C.

Thereafter, 854 parts by weight (ethylene oxide addition mole number: 19.4 mol) of ethylene oxide was slowly added thereto, and unreacted ethylene oxide was completely reacted until the residual ethylene oxide content became 5 ppm or less for 1 hour.

After the completion of the reaction, the temperature was lowered to 70 ° C or less and 0.22 parts by weight of acetic acid was added to neutralize the catalyst in the system, to obtain a polymer of allylamine ethylene oxide monomer and ethylene oxide monomer.

The final molecular weight of the polymer was about 1,000, and the ethylene oxide addition reaction time was 6 hours, with an unsaturation degree of 99.3% and a free-PEG of 0.6%.

Example  3

73 parts by weight of the allylamine ethylene oxide monomer obtained in the above Synthesis Example and 0.2 part by weight of potassium hydroxide (KOH) (95% Flake) were charged and the inside of the reactor was replaced with nitrogen five times with stirring, and then the reaction temperature was raised to 150 ° C.

Thereafter, 927 parts by weight (ethylene oxide addition mole number: 21.1 mol) of ethylene oxide was slowly added thereto, and unreacted ethylene oxide was completely reacted until the residual ethylene oxide content became 5 ppm or less for 1 hour.

After completion of the reaction, the temperature was lowered to 70 ° C or lower and 0.22 parts by weight of acetic acid was added to neutralize the catalyst in the system, to obtain a polymer of allylamine ethylene oxide monomer and ethylene oxide monomer.

The final molecular weight of the polymer was about 2,000 and the ethylene oxide addition reaction time was 6 hours with unsaturation of 99.2% and free-PEG of 0.7%.

Example  4

49 parts by weight of the allylamine ethylene oxide monomer obtained in the above Synthesis Example and 0.2 part by weight of potassium hydroxide (KOH) (95% Flake) were charged and the inside of the reactor was replaced with nitrogen five times with stirring, and then the reaction temperature was raised to 150 ° C.

Thereafter, 951 parts by weight (ethylene oxide addition mole number: 21.6 mol) of ethylene oxide was gradually added, and unreacted ethylene oxide was completely reacted until the residual ethylene oxide content became 1 ppm or less for 1 hour.

After completion of the reaction, the temperature was lowered to 70 ° C or lower and 0.22 parts by weight of acetic acid was added to neutralize the catalyst in the system, to obtain a polymer of allylamine ethylene oxide monomer and ethylene oxide monomer.

The final molecular weight of the polymer was about 3,000, and the ethylene oxide addition reaction time was 7 hours with an unsaturation degree of 99.1% and Free-PEG of 0.9%.

Manufacturing example  2: Manufacture of cement admixture

Example  5

80 parts by weight of the polymer (molecular weight: about 600) obtained in Example 1 and 50 parts by weight of water were placed in a four-necked PYREX flask equipped with a stirrer and a condenser, and the mixture was heated to 75 DEG C while stirring well.

Then, an aqueous solution of catalyst mixed with 1.4 parts by weight of ammonium persulfate and 50 parts by weight of water was injected into the reactor using a dropping pump for 3 hours and 30 minutes, and an aqueous monomer solution mixed with 6 parts by weight of acrylic acid and 50 parts by weight of water Lt; / RTI &gt; was injected into the reactor using a dropping pump for a period of time.

After the polymerization reaction was completed by injecting both the catalyst aqueous solution and the monomer aqueous solution, the mixture was aged at 75 ° C for 1 hour. The temperature was lowered to 40 ° C or less and 3 parts by weight of NaOH was added thereto to neutralize the cement admixture.

Example  6

An admixture was prepared in the same manner as in Example 5 except that the polymer obtained in Example 2 (molecular weight: about 1000) was added.

Example  7

An admixture was prepared in the same manner as in Example 5 except that the polymer obtained in Example 3 (molecular weight: about 2,000) was added.

Example  8

An admixture was prepared in the same manner as in Example 5 except that the polymer (molecular weight: about 3,000) was added in Example 4 above.

In order to compare the physical properties of the polycarboxylic acid-based cement admixture containing the vinylamine-based polyalkylene glycol of the present invention with the conventional ether-based polycarboxylic acid cement admixture and ester-based polycarboxylic acid cement admixture, polyalkylene glycol methylmethacrylate Further, a cement admixture using polyalkylene glycol vinylidene was prepared.

The preparation examples will be described in detail with reference to the following Comparative Example 1 and Comparative Example 2.

Comparative Example  One

550 parts by weight of methanol and an ethylene oxide adduct (molecular weight: about 2200), 43 parts by weight of metal acid, 0.5 part by weight of phenothiazine, 0.5 parts by weight of para toluene sulfonic acid, , And 296 parts by weight of cyclohexane, and the mixture was heated to 80 DEG C for 30 minutes.

Thereafter, dehydration condensation reaction was carried out over 7 hours, cyclohexane and the generated water were completely removed, and the mixture was cooled to 50 DEG C. Then, 3.4 parts by weight of sodium hydroxide (NaOH) was added to the total amount of sodium hydroxide solution dissolved in 391 parts by weight of distilled water To prepare polyalkylene glycol methyl ether dicarboxylic acid having a pH of 4 or less.

Thereafter, a solution A in which 4.87 parts by weight of ammonium persulfate was dissolved in 107 parts by weight of distilled water, 7 parts by weight of polyalkylene glycol methyl ether dicarboxylate, 49.8 parts by weight of metal acid, 3 parts by weight of mercaptopropionic acid acid, dissolved in 106 parts by weight of distilled water, was added dropwise at 75 DEG C over 3 hours and aged for 1 hour to obtain a polymer reactant in the form of a 50% aqueous solution.

Comparative Example  2

80 parts by weight of an ethylene oxide adduct of isobutanol (molecular weight: about 2,400) and 50 parts by weight of water were placed in a four-necked PYREX flask equipped with a stirrer and a condenser, and the mixture was heated to 75 DEG C while stirring well.

Then, an aqueous solution of a catalyst mixed with 1.4 parts by weight of ammonium persulfate and 50 parts by weight of water was injected into the reactor through a dropping pump for 3 hours and 30 minutes, and an aqueous monomer solution mixed with 6 parts by weight of acrylic acid and 50 parts by weight of water Lt; / RTI &gt; was injected into the reactor using a dropping pump for a period of time.

After the polymerization reaction was completed by injecting both the catalyst aqueous solution and the monomer aqueous solution as described above, the mixture was aged at 75 ° C for 1 hour, cooled to 40 ° C or less, and neutralized with 3 parts by weight of NaOH.

Manufacturing example  3: Concrete manufacturing

Table 1 below shows the concrete mixing ratios including the admixture prepared according to Examples 5 to 8 and Comparative Examples 1 to 2.

concrete
Mixing ratio W / C
(%) S / a
(%) W
(Kg) C + F / a
(Kg) S
(Kg) G
(Kg) AD
(%) 45.5 52.1 200 440 985 909 1.2

(Density: 2.62, Water Absorption Rate: 1.0, Water Content: 1.20) Total Powder Content: C: Water, C: Cement (Ssangyong Density: 3.15) + F / a = 440, AD: admixture (1.2%, total powder amount x 1.2%).

Example  9

400 parts by weight of cement (Ssangyong Density 3.15), 909 parts by weight of 25 mm aggregate (density 2.62, water absorption 1.0, water content 1.20), 985 parts by weight of washing yarn (density 2.58, water absorption 1.0, water content 6.70) 200 parts by weight of tap water and 29.9 parts by weight of the admixture prepared in Example 5 were thoroughly mixed to prepare a raw concrete.

Example  10

The raw concrete was prepared in the same manner as in Example 9, except that the admixture prepared in Example 6 was added.

Example  11

The raw concrete was prepared in the same manner as in Example 9, except that the admixture prepared in Example 7 was added.

Example  12

The raw concrete was prepared in the same manner as in Example 9, except that the admixture prepared in Example 8 was added.

Comparative Example  3

The raw concrete was prepared in the same manner as in Example 9, except that the admixture prepared in Comparative Example 1 was added.

Comparative Example  4

The raw concrete was prepared in the same manner as in Example 9, except that the admixture prepared in Comparative Example 2 was added.

< Experimental Example  1: Slump Flow  Experiment>

The slump flow was measured using the slump flow plate and the slump cone of the concrete produced in Examples 9 to 12, Comparative Examples 3 and 4.

After the initial slump flow was measured, the concrete slurry flow was re-measured after a certain period of time (90 minutes).

The results of the slump flow measured as described above are shown in Table 2 below.

division Slump flow (mm) Early After 90 minutes DELTA (initial-after 90 minutes) Example 9 570 * 560 280 * 270 -270 Example 10 580 * 560 300 * 300 -270 Example 11 680 * 660 410 * 400 -265 Example 12 590 * 590 300 * 280 -300 Comparative Example 3 640 * 630 280 * 270 -360 Comparative Example 4 610 * 600 320 * 310 -290

The results of the test are shown in Table 2. In the examples, the concrete to which the cement admixture of the present invention was applied was Comparative Example 3 (ester type) in which the cement admixture containing the vinylamine-based polyalkylene glycol of the present invention was not applied, Compared to concrete of Example 4 (ether system), relatively high fluidity was maintained, and the concrete slump value was excellent as well as the slump retention was relatively high.

This shows that the cement admixture of the present invention improves the dispersibility of the cement particles, thereby increasing the fluidity of the cement composition even at a small addition amount, and imparting good workability to the cement composition to form a concrete having high strength .

Claims (9)

Unsaturated vinylamine-based monomers;
Oxyalkylene monomers; And
A cement admixture polymerized from a carboxylic acid monomer and comprising a carboxylic acid copolymer represented by the following formula (3), an isomer thereof, or a mixture thereof:
(3)

(Wherein X and Y may be the same or different and each represents hydrogen, a methyl group or -COOM ₃ , and X or Y may form an anhydride ring with -COOM ₂ ,
Z is hydrogen, a methyl group or -CH ₂ COOM ₃ ,
M ₂ , and M ₃ may be the same or different from each other and are each hydrogen, an alkali metal, ammonium, or organic amine,
R ₁ , R ₂ and R ₃ may be the same or different and are each hydrogen or a methyl group,
R ^X is an alkylene group having 2 to 4 carbon atoms,
R ₄ and R ₅ may be the same or different and are each hydrogen, an alcohol having 3 to 6 carbon atoms or a saccharide having 3 to 6 carbon atoms,
m and n are an average number of moles of oxyalkylene groups, and are integers of 1 to 50,
X 'is an alkyl group having 1 to 5 carbon atoms,
a and b are integers of 1 to 20, and k is an integer of 1 to 7. The method according to claim 1,
Wherein the unsaturated vinylamine monomer is a cement admixture comprising a compound represented by the following formula (1), an isomer thereof, or a mixture thereof:
[Chemical Formula 1]

(Wherein R ₁ , R ₂ and R ₃ may be the same or different and are each hydrogen or a methyl group,
And X 'is an alkyl group having 1 to 5 carbon atoms.
3. The method of claim 2,
Wherein the cement admixture further comprises a condensation monomer of the unsaturated vinylamine-based monomer and the oxyalkylene-based monomer,
Wherein the condensation monomer is a cement admixture comprising a compound represented by the following formula (2), an isomer thereof, or a mixture thereof:
(2)

(Wherein R ₁ , R ₂ and R ₃ may be the same or different and are each hydrogen or a methyl group,
R ₄ and R ₅ may be the same or different and each is hydrogen or an alcohol having 3 to 6 carbon atoms or a saccharide having 3 to 6 carbon atoms,
X 'is an alkyl group having 1 to 5 carbon atoms,
R ^X may be the same as or different from X ', and each represents an alkylene group having 2 to 18 carbon atoms,
m and n are an average number of moles of oxyalkylene groups, and are integers of 1 to 50, and may be the same or different.
The method of claim 3,
The condensation monomer represented by Formula 2 is any one of poly (meth) aryl ether of a glycerin-ethylene oxide adduct and polyallylamine monomer of a glucose-ethylene oxide adduct.
5. The method of claim 4,
Wherein the carboxylic acid-based monomer comprises at least one of acrylic acid, methacrylic acid, maleic acid, maleic anhydride, crotonic acid, citraconic acid, citraconic anhydride, itaconic acid, itaconic anhydride and fumaric acid.
delete The method of claim 3,
The cement admixture comprising 20 to 80% by weight of the monomer represented by Formula 1 and 20 to 80% by weight of the condensation monomer represented by Formula 2, based on the total weight of the cement admixture.
The method according to claim 1,
Wherein the carboxylic acid-based copolymer has a weight average molecular weight of 20,000 to 50,000.
In concrete containing cement, water, aggregate, and washing yarn,
A concrete composition comprising 0.1 to 10 parts by weight of the cement admixture of claim 1 per 100 parts by weight of cement.