CEMENT DISPERSANT, METHOD FOR PREPARING SAME, AND MORTAR-CONCRETE ADMIXTURE USING SAME

Abstract

The present invention relates to a polycarbonic acid-based cement dispersant, a method for preparing the same, and a mortar-concrete admixture using the polycarbonic acid-based cement dispersant.

The cement dispersant of the present invention and the mortar-concrete admixture using the cement dispersant are applied to a cement composition such as a cement paste, mortar, concrete, etc., enhance a dispersion and retention force between cement molecules, have excellent fluidity due to the suppression of slump loss, and have an effect of improving workability, such as shortening a concrete mixing time by 20% or more. Further, the mortar-concrete admixture using the cement dispersant of the present invention has an effect of providing a very good concrete condition and an appropriate compressive strength over time.

Claims

1. A cement dispersant which is a polymer composition represented by Formula (f), wherein the polymer composition comprises a copolymer including a compound represented by Formula (a) and a compound represented by at least one of Formulas (d) and (e), and the compound of Formula (a) is formed by a ring-opening reaction of an acid anhydride represented by Formula (c) with a metharyl (poly)alkylene glycol ether compound represented by Formula (b), and is able to be used alone or in combination with the compound of Formula (b): ##STR00019## wherein each of R1 to R3 represents a hydrogen atom, or at least one alkyl group having 1 to 30 carbon atoms, R4 represents an alkyl group having 1 to 30 carbon atoms, X represents an alkyl group having 0 to 30 carbon atoms, Y represents an alkyl group having 1 to 30 carbon atoms, and m represents the average number of moles of added oxyalkylene and alkyl groups and is a number ranging from 1 to 400; ##STR00020## wherein each of R1 to R3 represents a hydrogen atom, or at least one alkyl group having 1 to 30 carbon atoms, R4 represents an alkyl group having 1 to 30 carbon atoms, X represents an alkyl group having 0 to 30 carbon atoms, and m represents the average number of moles of added oxyalkylene and alkyl groups and is a number ranging from 1 to 400; ##STR00021## wherein Y represents a material, such as an alkene, a phenyl, an alkyl, an aryl, an aliphatic cyclic compound, or an aromatic compound, which has 1 to 30 carbon atoms; ##STR00022## wherein each of R5 to R7 represents a hydrogen atom, or an alkyl, alkylene, allyl or acid, all of which have 1 to 30 carbon atoms, and M represents a hydrogen atom, or a compound such as a monovalent or divalent metal and ammonia, and a primary, secondary or tertiary amine; ##STR00023## wherein each of R8 to R9 represents an alkyl group having 1 to 30 carbon atoms, and M represents a hydrogen atom, or a compound such as a monovalent or divalent metal and ammonia, and a primary, secondary or tertiary amine; and ##STR00024## wherein each of R1 to R3 and R5 to R7 represents a hydrogen atom, or an alkyl group having 1 to 30 carbon atoms, each of R4 and R8 to R9 represents an alkyl group having 1 to 30 carbon atoms, X represents an alkyl group having 0 to 30 carbon atoms, each of m, o, p, q and r represents the average number of moles, provided that m is in a range of 1 to 400 moles, o, p and r are in a range of 0 to 400 moles, and q is in a range of 0.1 to 400 moles, and M represents a hydrogen atom, a compound such as a monovalent or divalent metal and ammonia, and a primary, secondary or tertiary amine.

2. The cement dispersant of claim 1, wherein the average number of moles of the oxyalkylene and alkyl groups in the compound of Formula (a) is in a range of 1 to 400.

3. The cement dispersant of claim 1, wherein the polymer composition represented by Formula (f) has a weight average molecular weight of 10,000 to 300,000.

4. The cement dispersant of claim 1, wherein the mixing ratios of the compounds of Formulas (a), (b), (d) and (e) are based on the molar ratios, the sum of the molar ratios of the compounds of Formulas (a) and (b) is less than or equal to the sum of the molar ratios of the compounds of Formulas (d) and (e), the polymer composition of Formula (f) essentially comprises the compound of Formula (a), and is able to be used in combination with the compound of Formula (b), at least one of the compounds of Formulas (d) and (e) is able to be used, and at least one of the compounds of Formulas (d) and (e) has to be used.

5. The cement dispersant of claim 1, wherein the compounds of Formulas (a), (b), (d), and (e) are polymerized at a molar ratio of 10 to 100:0 to 70:0 to 150:0 to 150.

6. A mortar-concrete admixture comprising the cement dispersant represented by Formula (f) defined in claim 1.

7. A method for preparing a cement dispersant which is a polymer composition represented by Formula (f), wherein the polymer composition comprises a copolymer including a compound represented by Formula (a) and a compound represented by at least one of Formulas (d) and (e), and the compound of Formula (a) is formed by a ring-opening reaction of an acid anhydride represented by Formula (c) with a metharyl (poly)alkylene glycol ether compound represented by Formula (b), and is able to be used alone or in combination with the compound of Formula (b): ##STR00025## wherein each of R1 to R3 represents a hydrogen atom, or at least one alkyl group having 1 to 30 carbon atoms, R4 represents an alkyl group having 1 to 30 carbon atoms, X represents an alkyl group having 0 to 30 carbon atoms, Y represents an alkyl group having 1 to 30 carbon atoms, and m represents the average number of moles of added oxyalkylene and alkyl groups and is a number ranging from 1 to 400; ##STR00026## wherein each of R1 to R3 represents a hydrogen atom, or at least one alkyl group having 1 to 30 carbon atoms, R4 represents an alkyl group having 1 to 30 carbon atoms, X represents an alkyl group having 0 to 30 carbon atoms, and m represents the average number of moles of added oxyalkylene and alkyl groups and is a number ranging from 1 to 400; ##STR00027## wherein Y represents a material, such as an alkene, a phenyl, an alkyl, an aryl, an aliphatic cyclic compound, or an aromatic compound, which has 1 to 30 carbon atoms; ##STR00028## wherein each of R5 to R7 represents a hydrogen atom, or an alkyl, alkylene, allyl or acid, all of which have 1 to 30 carbon atoms, and M represents a hydrogen atom, or a compound such as a monovalent or divalent metal and ammonia, and a primary, secondary or tertiary amine; ##STR00029## wherein each of R8 to R9 represents an alkyl group having 1 to 30 carbon atoms, and M represents a hydrogen atom, or a compound such as a monovalent or divalent metal and ammonia, and a primary, secondary or tertiary amine; and ##STR00030## wherein each of R1 to R3 and R5 to R7 represents a hydrogen atom, or an alkyl group having 1 to 30 carbon atoms, each of R4 and R8 to R9 represents an alkyl group having 1 to 30 carbon atoms, X represents an alkyl group having 0 to 30 carbon atoms, each of m, o, p, q and r represents the average number of moles, provided that m is in a range of 1 to 400 moles, o, p and r are in a range of 0 to 400 moles, and q is in a range of 0.1 to 400 moles, and M represents a hydrogen atom, a compound such as a monovalent or divalent metal and ammonia, and a primary, secondary or tertiary amine.

8. The method of claim 7, wherein the average number of moles of the oxyalkylene and alkyl groups in the compound of Formula (a) is in a range of 1 to 400.

9. The method of claim 7, wherein the polymer composition represented by Formula (f) has a weight average molecular weight of 10,000 to 300,000.

10. The method of claim 7, wherein the mixing ratios of the compounds of Formulas (a), (b), (d) and (e) are based on the molar ratios, the sum of the molar ratios of the compounds of Formulas (a) and (b) is less than or equal to the sum of the molar ratios of the compounds of Formulas (d) and (e), the polymer composition of Formula (f) essentially comprises the compound of Formula (a), and is able to be used in combination with the compound of Formula (b), at least one of the compounds of Formulas (d) and (e) is able to be used, and at least one of the compounds of Formulas (d) and (e) has to be used.

11. The method of claim 7, wherein the compounds of Formulas (a), (b), (d), and (e) are polymerized at a molar ratio of 10 to 100:0 to 70:0 to 150:0 to 150.

12. A mortar-concrete admixture comprising the cement dispersant represented by Formula (f) defined in claim 2.

13. A mortar-concrete admixture comprising the cement dispersant represented by Formula (f) defined in claim 3.

14. A mortar-concrete admixture comprising the cement dispersant represented by Formula (f) defined in claim 4.

15. A mortar-concrete admixture comprising the cement dispersant represented by Formula (f) defined in claim 5.

Description

EXAMPLE 1

Preparation of SuH

[0057] After a thermometer, an agitator, and a reflux condenser were installed in a glass reactor, 3,120 g (EO moles: 60) of a metharyl (poly)alkylene glycol ether compound was put into the glass reactor, and heated to 60 C. to vacuum-collect and completely remove moisture included in the compound. Thereafter, 62.44 g of a succinic anhydride and 15.91 g of p-toluenesulfonic acid were added thereto. When the addition was completed, the temperature was increased, and the resulting mixture was heated to a temperature of approximately 90 C. After the mixture was heated for approximately 22 hours, an acid value of the mixture was measured to be 22.723 ml/g (a reaction rate: 99.4%), and the reaction was then stopped.

EXAMPLE 2

Preparation of PhH

[0058] After a thermometer, an agitator, and a reflux condenser were installed in a glass reactor, 3,120 g (EO moles: 60) of a metharyl (poly)alkylene glycol ether compound was put into the glass reactor, and heated to 60 C. to vacuum-collect and completely remove moisture included in the compound. Thereafter, 173 g of a phthalic anhydride and 3 g of p-toluenesulfonic acid were added thereto. When the addition was completed, the temperature was increased, and the resulting mixture was heated to a temperature of approximately 90 C. After the mixture was heated for approximately 66 hours, an acid value of the mixture was measured to be 22.94 ml/g (a reaction rate: 99.3%), and the reaction was then stopped.

EXAMPLE 3

Preparation of MalH

[0059] After a thermometer, an agitator, and a reflux condenser were installed in a glass reactor, 3,120 g (EO moles: 60) of a metharyl (poly)alkylene glycol ether compound was put into the glass reactor, and heated to 60 C. to vacuum-collect and completely remove moisture included in the compound. Thereafter, 114.73 g of a maleic anhydride and 16.2 g of p-toluenesulfonic acid were added thereto. When the addition was completed, the temperature was increased, and the resulting mixture was heated to a temperature of approximately 90 C. After the mixture was heated for approximately 3 hours, an acid value of the mixture was measured to be 23.2 ml/g (a reaction rate: 99.8%), and the reaction was then stopped.

[0060] [Preparation of Polymer Composition of Formula (f)]

EXAMPLE 4

[0061] After a thermometer, an agitator, a reflux condenser, and a dropping funnel were installed in a glass reactor, 720 g of the compound prepared in Example 1 and 50 g of ion-exchange water were added thereto, and the resulting mixture was heated to 65 C. When the temperature reached a target temperature, 4.84 g of 3-mercaptopropionic acid, 64.8 g of acrylic acid, and 6.04 g of sodium persulfate were added dropwise for 3 to 3.5 hours. Thereafter, the mixture was aged for 3 hours, and the reaction was then stopped. Then, the resulting reaction mixture was cooled to 50 C. or less to obtain an aqueous copolymer solution having a weight average molecular weight of 35,412.

EXAMPLE 5

[0062] After a thermometer, an agitator, a reflux condenser, and a dropping funnel were installed in a glass reactor, 360 g of the compound prepared in Example 1, 270 g of a metharyl (poly)alkylene glycol ether compound, and 50 g of ion-exchange water were added thereto, and the resulting mixture was heated to 65 C. When the temperature reached a target temperature, 4.84 g of 3-mercaptopropionic acid, 64.8 g of acrylic acid, and 6.04 g of sodium persulfate were added dropwise for 3 to 3.5 hours. Thereafter, the mixture was aged for 3 hours, and the reaction was then stopped. Then, the resulting reaction mixture was cooled to 50 C. or less to obtain an aqueous copolymer solution having a weight average molecular weight of 38,193.

EXAMPLE 6

[0063] After a thermometer, an agitator, a reflux condenser, and a dropping funnel were installed in a glass reactor, 144 g of the compound prepared in Example 1, 432 g of a metharyl (poly)alkylene glycol ether compound, and 50 g of ion-exchange water were added thereto, and the resulting mixture was heated to 65 C. When the temperature reached a target temperature, 4.84 g of 3-mercaptopropionic acid, 64.8 g of acrylic acid, and 6.04 g of sodium persulfate were added dropwise for 3 to 3.5 hours. Thereafter, the mixture was aged for 3 hours, and the reaction was then stopped. Then, the resulting reaction mixture was cooled to 50 C. or less to obtain an aqueous copolymer solution having a weight average molecular weight of 41,856.

COMPARATIVE EXAMPLE 1

[0064] After a thermometer, an agitator, a reflux condenser, and a dropping funnel were installed in a glass reactor, 210 g of a metharyl (poly)alkylene glycol ether compound, 17.05 g of maleic acid, and 100 g of ion-exchange water were added thereto, and the resulting mixture was heated to 65 C. Thereafter, 9.8 parts by weight of hydrogen peroxide was added to a reaction vessel. Then, 9 g of acrylic acid, 0.635 g of L-ascorbic acid and 6.03 g of ion-exchange water were added dropwise for 3 hours and 3.5 hours, respectively. After the dropwise addition was completed, the reaction product was kept at 65 C. for an hour. When the reaction was completed, the reaction product was adjusted with an aqueous NaOH solution to have a pH value of 7, thereby obtaining an aqueous copolymer solution.

COMPARATIVE EXAMPLE 2

[0065] After a thermometer, an agitator, a reflux condenser, and a dropping funnel were installed in a glass reactor, 210 g of a metharyl (poly)alkylene glycol ether compound, 21.35 g of maleic acid, and 142 g of ion-exchange water were added thereto, and the resulting mixture was heated to 65 C. Thereafter, 4.39 g of an aqueous hydrogen peroxide solution was added to a reaction vessel. Then, 5.9 g of 2-hydroxyethyl acrylate, 0.284 g of L-ascorbic acid, and 5.4 g of ion-exchange water were added dropwise for 3 hours and 3.5 hours, respectively. After the dropwise addition was completed, the reaction product was kept at 65 C. for an hour. When the reaction was completed, the reaction product was cooled to room temperature, and then adjusted with an aqueous NaOH solution to have a pH value of 7, thereby obtaining an aqueous copolymer solution.

COMPARATIVE EXAMPLE 3

[0066] After a thermometer, an agitator, a reflux condenser, and a dropping funnel were installed in a glass reactor, 43.37 g of a metharyl (poly)alkylene glycol ether compound, and 25.48 g of ion-exchange water were added thereto, and the resulting mixture was heated to 60 C. Thereafter, 3.0 g of an aqueous solution of 2% hydrogen peroxide was added to a reaction vessel. Then, 1.92 g of acrylic acid was added dropwise for 1.5 hours. When the dropwise addition was completed, 4.08 g of acrylic acid was again added dropwise for 1.5 hours. An aqueous solution including 0.14 g of 3-mercaptopropionic acid, 0.08 g of L-ascorbic acid, and 15.94 g of ion-exchange water was added dropwise for 3.5 hours while the acrylic acid was primarily added dropwise. When the dropwise addition was completed, the reaction product was kept at 60 C. for an hour, and then cooled. Then, a polymerization reaction was completed. Subsequently, the reaction product was adjusted with an aqueous NaOH solution to have a pH value of 7, thereby obtaining an aqueous copolymer solution.

EXAMPLES 7 to 12

[0067] Examples 7 to 12 were carried out using the monomers synthesized in Examples 1 to 3 by adjusting the ratios of the monomers synthesized in Examples 4 to 6. The results of the copolymers thus prepared are listed in Table 1 below.

TABLE-US-00001 TABLE 1 Results Monomer Molar Viscosity Specific Items acronym Monomer ratio of monomers (cps at 25 C.) gravity pH Example 4 SuH-100 AA 4:1 420 1.102 1.89 Example 5 SuH-50 AA 4:1 432 1.1 2.18 Example 6 SuH-20 AA 4:1 450 1.098 2.4 Example 7 PhH-100 AA 4:1 340 1.102 1.88 Example 8 PhH-50 AA 4:1 370 1.1 2.14 Example 9 PhH-20 AA 4:1 405 1.102 2.42 Example 10 MalH-100 AA 4:1 960 1.102 1.7 Example 11 MalH-50 AA 4:1 1,096 1.104 1.8 Example 12 MalH-20 AA 4:1 1,382 1.096 1.96 [Compound acronym] AA: acrylic acid
[SuH-100 means that an SuH monomer is used alone, and each of the numerals 50 and 20 represents a ratio of SuH. A metharyl (poly)alkylene glycol ether monomer is used so that the other ratio reaches a total of 100%. PhH and MalH are also used for polymerization at the same ratios as in the method.

EXAMPLES 13 to 16

[0068] Polymerizations were performed in the same manner as in Example 4, except that the monomers synthesized in Examples 1 to 3 were used at a fixed ratio, and the different types and ratios of the other monomers were used. The polymer compositions thus prepared are listed in Table 2 below.

TABLE-US-00002 TABLE 2 Results Molar Active Viscosity Monomer ratio of ingredient (cps at Specific Items acronym Monomer monomers (%) 25 C.) gravity pH Example 13 SuH- AA, 3.5:0.5 50.5 340 1.104 1.98 100 MAA Example 14 SuH- AA, 3.5:0.5 50.5 370 1.102 1.99 100 HEA Example 15 PhH- AA, MA 3.5:0.5 50.5 210 1.104 1.8 100 Example 16 PhH- AA, 3.5:0.5 50.5 230 1.096 1.96 100 MAA Comparative VPEG AA, MA 1.99:1.43 50.5 172 1.106 6.58 Example 1 Comparative VPEG MA, 1.44:0.58 50.5 117 1.112 6.75 Example 2 HEA Comparative VPEG AA 3.5:0.5 50.5 470 1.102 3.51 Example 3 [Compound acronyms] AA: acrylic acid, MAA: methacrylic acid, MA: maleic acid, and HEA: 2-hydroxyethylacrylate

[0069] [Measurement of Weight Average Molecular Weights]

[0070] The weight average molecular weights of the samples polymerized in Examples 4 to 16 and Comparative Examples 1 to 3 were measured. The results are listed in Table 3 below.

TABLE-US-00003 TABLE 3 Molecular Items weight Example 4 35,126 Example 5 38,193 Example 6 41,856 Example 7 23,240 Example 8 26,713 Example 9 33,802 Example 10 332,122 Example 11 249,745 Example 12 153,407 Example 13 34,124 Example 14 37,046 Example 15 33,907 Example 16 35,378 Comparative 29,821 Example 1 Comparative 28,989 Example 2 Comparative 35,216 Example 3

[0071] The conditions used to measure the weight average molecular weight of the copolymer are as follows.

[0072] 1) Equipment: Gel permeation chromatograph (GPC) commercially available from WATERS Corp.

[0073] 2) Detector: differential spectrometry refractive index (RI) detector (Ditector 2414 commercially available from WATERS Corp.)

[0074] 3) Eluent: Type: deionized water (for HPLC), Flow rate: 0.8 ml/min

[0075] 4) Type of column: Ultrahydrogel (640 mm) commercially available from WATERS Corp.

[0076] 5) Column temperature: 25 C.

[0077] 6) Standard sample: Used after a calibration curve was plotted against polyethylene glycols having a peak-top molecular weight (M.sub.p) of 1670, 5000, 25300, 440000, 78300,152000, 326000, and 55800.

[0078] [Preparation of Concrete Admixture]

[0079] Concrete admixtures were prepared using the aqueous copolymer solution prepared in Examples 4 to 16 and Comparative Examples 1 to 3.

[0080] 1) An active ingredient of each of the aqueous copolymer solution prepared in Examples 4 to 16 and Comparative Examples 1 to 3 is measured.

[0081] 2) The active ingredient of each of the aqueous copolymer solutions is adjusted to be 20%, and another admixture is added at a content of approximately 0.1% of the total weight of the aqueous copolymer solution (In this case, when there is no admixture to be added, it is possible to express performance using only the aqueous copolymer solution).

[0082] [Method for Measuring Active Ingredient]

[0083] 1) The mass of a polymer to be measured is measured.

[0084] 2) The measured polymer is put into a dryer whose temperature is set to 105 C., and dried for 3 hours.

[0085] 3) After the elapse of 3 hours, the polymer sample is taken out from the dryer, and then cooled at room temperature for 20 minutes in a desicator.

[0086] 4) When Step 3) is ended, the mass of the polymer sample is measured.

[0087] 5) Steps 1) to 4) are performed three times to prepare three test samples.

[0088] 6) The active ingredient is calculated according to the following equation.

[00002]$\mathrm{Active}.Math..Math.\mathrm{ingredient}.Math..Math.\left(\%\right)=\frac{\mathrm{Weight}.Math..Math.\left(g\right).Math..Math.\mathrm{of}.Math..Math.\mathrm{polymer}.Math..Math.\mathrm{sample}.Math..Math.\mathrm{after}.Math..Math.\mathrm{drying}}{\mathrm{Weight}.Math..Math.\left(g\right).Math..Math.\mathrm{of}.Math..Math.\mathrm{polymer}.Math..Math.\mathrm{sample}.Math..Math.\mathrm{before}.Math..Math.\mathrm{drying}}100$

[0089] 7) An average of the measured masses of the test samples is determined as a ratio of the active ingredient of the polymer.

[0090] Based on the above-described method, the admixtures of the present invention was subjected to a concrete test, and then compared and analyzed.

[0091] [Concrete Test]

[0092] 1) Slump test: KS F 2402

[0093] 2) Measurement of air volume: KS F 2409

[0094] 3) A concrete formulation is prepared using the following compositions.

[0095] Water: 165 kg

[0096] Cement (General Portland cement): 423 kg

[0097] Fly ash: 47 kg

[0098] Aggregate I (Type: fine aggregate): 760 kg

[0099] Aggregate II (Type: 25 mm crushed stone): 946 kg

[0100] 4) Experimental Method:

[0101] A concrete mixture prepared from the above-described components was thoroughly mixed, and the following test methods were performed to measure an initial flow value, a flow value after 60 minutes, and a volume of air.

[0102] [Slump Test (KS F 2402)]

[0103] 1) The inside of a slump cone is wiped with a damp cloth, and the slump cone is placed on a watertight flat plate.

[0104] 2) A sample is added at approximately (Depth: approximately 7 cm) of the volume of a slump cone, and the entire surface of the sample is uniformly tamped 25 times using a tamping bar.

[0105] 3) A sample is added at (Depth: approximately 16 cm) of the volume of the slump cone, and tamped 25 times using the tamping bar. In this case, the depth of concrete into which the tamping bar is stuck is approximately 9 cm.

[0106] 4) Finally, a sample is added to the slump cone to such a level that the sample brims over, and tamped 25 times using the tamping bar.

[0107] 5) The surface of the sample is flattened to a top surface of the slump cone.

[0108] 6) The slump cone is carefully pulled out upward.

[0109] 7) The depth of the sunken concrete is measured with an accuracy of 5 mm.

[0110] [Air Test (KS F 2409)]

[0111] 1) A vessel is divided into three layers having substantially the same height, and completely filled with a sample. Then, each of the layers is uniformly tamped ten times, and a side of the vessel is struck with a wooden hammer five times.

[0112] 2) Next, the sample is flattened with the remaining sample using a ruler. An upper flange portion of the vessel, and a lower flange portion of a cap are wiped cleanly, and the cap is carefully attached to the vessel to circulate air through the cap. Then, the cap is tightened to prevent air from escaping from the vessel, and an air pressure in the vessel is matched with an initial pressure.

[0113] 3) After approximately 5 seconds, an actuator disk is fully opened. A side of the vessel is struck with a wooden hammer so that a pressure is uniformly applied to respective portions of concrete. The actuator disk is fully opened again, and an air volume scale of a pressure gauge is read to one decimal place until a needle is stabilized.

[0114] [Compressive Strength Test]

[0115] This test was carried out based on the above-described concrete mixture, and a test piece specimen for a compressive strength test was manufactured, as follows.

[0116] 1) The number of test piece specimens is set to 3.

[0117] 2) A mineral oil is applied to a mold before concrete is poured into the mold.

[0118] 3) To fill the mold with concrete, the mold is divided into three layers, and filled with the concrete using a tamping bar. Then, each of the layers is tamped 25 times.

[0119] 4) The mold is removed 24 to 48 hours after the concrete is poured into the mold. Thereafter, the concrete is aged at a temperature of 18 to 24 C. under a wet condition until a compressive strength test is carried out.

TABLE-US-00004 TABLE 4 Admixture contents, flow values over time, air volumes, and changes in compressive strength Compressive strength Content Flow (mm) Air Concrete (kgf/cm.sup.2) Items (%) Initial 60 min (%) condition Day 3 Day 7 Day 28 Example 4 1.0 590 600 540 550 3.5 321 402 438 Example 5 1.0 600 600 560 570 3.5 325 410 440 Example 6 1.0 580 580 520 510 3.4 316 391 433 Example 7 1.0 570 570 490 500 2.8 295 367 427 Example 8 1.0 580 580 530 550 2.8 300 380 415 Example 9 1.0 590 600 540 550 2.7 322 404 440 Example 10 1.0 440 450 320 320 3.1 318 398 429 Example 11 1.0 420 430 330 330 3.1 318 397 429 Example 12 1.0 460 470 370 370 3.2 318 396 428 Example 13 1.0 580 580 530 550 2.9 310 410 430 Example 14 1.0 560 560 540 550 2.9 314 409.5 431 Example 15 1.0 570 560 500 500 3.2 319 403 432 Example 16 1.0 550 560 440 450 3.4 320 401 440 Comparative 1.0 390 400 180 190 2.8 285.5 307 357 Example 1 Comparative 1.0 300 310 120 130 2.6 X 275 316 367 Example 2 Comparative 1.0 530 540 460 470 2.8 317 390 411 Example 3 In the Table, the concrete conditions are expressed as feelings when the concrete is mixed using a scoop. The concrete conditions are expressed according to the goodness of light and soft feelings, as follows: Very good: , Good: , Mean: , and Poor: X.

[0120] [Mixing Time Test]

[0121] This test was carried out for 30, 60, and 90 seconds, considering that concrete was generally mixed for a mixing time of 40 to 60 seconds in a ready-mixed concrete (remicon) factory. In this case, the mixing of the concrete, and the measurement of an initial flow value were carried out according to the above-described test method. It was revealed that, when the admixture prepared in each of Examples 4 and 9 was added, the condition of concrete was very good even when the concrete was mixed for a mixing time of 30 seconds, and thus the concrete mixing time was able to be shortened by 20% or more.

TABLE-US-00005 TABLE 5 Flow values over time according to mixing time Mixing Content Flow (mm) Concrete Items time (sec.) (%) Initial Air (%) condition Example 4 30 1.0 630 620 3.5 60 1.0 590 600 3.4 90 1.0 570 580 3.6 Example 9 30 1.0 620 620 2.7 60 1.0 590 600 2.7 90 1.0 570 580 2.7 Example 11 30 1.0 450 460 3.3 60 1.0 420 430 3.1 90 1.0 410 420 3.1 Example 15 30 1.0 570 570 3.4 60 1.0 560 570 3.2 90 1.0 530 550 3.3 Comparative 30 1.0 330 340 2.9 Example 1 60 1.0 390 410 2.8 90 1.0 300 310 2.8 In the Table, the conditions of concrete are expressed as feelings when the concrete is mixed using a scoop. The concrete conditions are expressed according to the goodness of light and soft feelings, as follows: Very good: , Good: , Mean: , and Poor: X.