JPH10291847A - Cement mixing agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cement mixing agent without causing a coagulation retardation and exhibiting an excellent fluid effect, a slump loss suppressing effect and material separation resistance. SOLUTION: A cement mixing agent is composed of a formaldehyde co- polycondensate with polyoxyalkylene monoamine (A), one or more kinds of compds. (B) selected from the group consisting of melamine or its deriv., one or more kinds of compds. (C) selected from the group consisting of aminobenzenesulfonic acid or its deriv. or alkylaminobenzenesulfonic acid or its deriv., an other monomer (D) capable of co-polycondensating the formaldehyde with the polyoxyalkylene monoamine and/or a compd. (E) producing a sulfone group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an admixture for a cement or a cement composition, and more particularly, to the addition of a hydraulic cement composition such as a cement paste, mortar, concrete or the like when kneading to improve the workability. The present invention relates to a cement admixture to be improved.

[0002]

2. Description of the Related Art
Various types of organic compounds added to cement, particularly as a cement water reducing agent, are known. Representative examples thereof include salts of highly condensed β-naphthalenesulfonic acid formaldehyde, salts of melaminesulfonic acid formaldehyde condensate, ligninsulfonic acid salts, oxycarboxylic acids, and the like. When these compounds are added to a kneaded product composed of cement, water and aggregate, sufficient workability can be obtained even if the amount of water during kneading is reduced. Therefore, there is an advantage that workability is improved, and since the water-cement ratio can be reduced, it is useful for enhancing the strength of a hydraulic cement composition such as cement paste, mortar, and concrete.

[0003] However, in general, cement paste,
Mortar, hydraulic cement composition such as concrete,
With the passage of time after kneading, the fluidity is lost. This phenomenon occurs when the organic compound added as the cement water reducing agent is used, and particularly, β-
This is remarkable when a salt of a highly condensed naphthalenesulfonic acid formaldehyde or the like is used, and depending on the composition of the concrete, a phenomenon in which the slump is reduced to half or less within 30 minutes after kneading is observed. Due to the phenomenon that the slump loss is large, the following problems occur. In other words, the concrete composition may be pumped by pumping concrete, but if the pumping is temporarily interrupted due to a break time or various troubles at that time, the pumping pressure may suddenly increase when resuming, And piping may be blocked. In addition, since the fluidity is reduced, the compact may not be sufficiently compacted in the mold, and a defective portion may be generated.

In order to suppress slump loss, various water reducing agents have been developed in the past. For example, a substance in which the functional group is dissociated by an alkali in concrete, a so-called sustained-release high-performance water reducing agent (Japanese Patent Publication No. 63-5346) is known. Further, a water-soluble vinyl copolymer (Japanese Patent Publication No. 6-60042) is known, in which a new functional group appears by being hydrolyzed in an alkali and suppresses slump loss. Further, for the purpose of maintaining a slump due to steric hindrance of a molecular chain, a polyalkylene glycol monoester monomer having an unsaturated bond and a (meth) acrylic acid monomer and / or an unsaturated dicarboxylic acid monomer (JP-B-59-18338, JP-B-2)
JP-B-7897, JP-B-2-7898, JP-B-2-7901, JP-B-2-8983, JP-B2-111542, JP-B5-111057, and JP-B6-88817. And water-soluble vinyl copolymers (these are generically referred to as polycarboxylic acid type). Further, a condensate in which a polyalkylene glycol chain is introduced into an aromatic compound (Japanese Patent Laid-Open No. 6-3 / 1994)
No. 40459) has also been recently developed.

[0005] However, while these compounds exhibit excellent flow effects, they have various problems. First,
In the case of slow-release high-performance water reducing agents that work with alkali in concrete and water-soluble vinyl copolymers that are newly hydrolyzed by alkali hydrolysis to replenish functional groups and suppress slump loss,
Carboxyl groups appear over time. This carboxyl group has a large bonding force with calcium ions. Therefore,
These compounds have a problem that calcium ions in the cement are trapped and the setting delay is increased.

Furthermore, a polycarboxylic acid having an oxyalkylene chain in the molecule has high air entrainment, and it is difficult to control the amount of air in concrete. In reality, the amount of air is controlled using an antifoaming agent, but the amount of air fluctuates greatly depending on the kneading conditions in the concrete mixer, the agitator conditions of the mixer truck, and the transport time,
There is a problem that it is difficult to use. Furthermore, (meta)
These compounds have a carboxyl group in the molecule because they are copolymerized using acrylic acid monomers and / or unsaturated dicarboxylic acid monomers. Therefore, there is a problem that the curing delay is increased depending on the composition ratio. That is, the initial strength of the cement mortar or concrete decreases. In addition, when a large slump is used, that is, when soft mortar or concrete is used, material separation may occur, which is a problem.

Further, a condensate in which a polyalkylene glycol chain is introduced into an aromatic compound has a problem that a flow effect similar to that of a polycarboxylic acid having an oxyalkylene chain in a molecule cannot be recognized.

[0008]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve these problems, and as a result, it has been found that a cocondensate having a specific molecular structure has an excellent curing delay without remarkable curing delay. The present invention has been found to exhibit a dispersing effect and a slump holding effect, and further has a remarkable material separation resistance, leading to the present invention.

That is, the present invention relates to one or more compounds (B) selected from the group consisting of polyoxyalkylene monoamines (A), melamine or derivatives thereof, aminobenzenesulfonic acid or derivatives thereof, and alkylaminobenzenesulfones. One or more compounds (C) selected from the group consisting of acids or derivatives thereof, and other monomers (D) capable of co-condensing polyoxyalkylene monoamine with formaldehyde, and / or forming a sulfone group The present invention relates to a cement admixture comprising a formaldehyde co-condensate with a compound (E).

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. As the polyoxyalkylene monoamine (A),
General formula (1) General formula (1) R ₁ O— (AO) _m (BO) _n —R ₂ —NH ₂ where R ₁ , R ₂ : alkyl group having 1 to 5 carbon atoms AO, BO: carbon Oxyalkylene groups AO and BO of the numbers 2 to 5 are block and / or random m, n: an integer of 0 to 300. However, a compound represented by 300 ≧ m + n ≧ 4, that is, polyoxyethylene monoamine,
Polyoxyalkylene monoamines such as polyoxypropylene monoamine and polyoxyethylene oxypropylene monoamine. This oxyalkylene moiety has 2 to 5 carbon atoms. When the number of carbon atoms exceeds 5, the water solubility decreases, and not only co-condensation becomes difficult, but also an excellent flow effect cannot be obtained.

The oxyalkylene may be of one type, but may be one in which two or more types of oxyalkylene are bonded in a block or randomly. The number of repeating units is preferably from 4 to 300, and more preferably from 7 to 100. When the number of the repeating units is less than 4, the obtained cement admixture does not have a sufficient flow effect and a slump loss suppressing effect is not sufficient. Also, 3
If it exceeds 00, co-condensation does not proceed well.

The step of adding the compound represented by the general formula (I) may be any step of synthesizing the co-condensation of the present invention.
That is, it may be charged into the reactor in advance at the start of the reaction, or may be added immediately before or immediately after pH adjustment when formaldehyde co-condensation reaction is performed under the condition of a weakly acidic pH.

The compounds represented by the general formula (I) can be used in combination of one or more kinds. Furthermore, the addition amount is preferably 0.001 to 0.5 mol, more preferably 0.005 to 1 mol of one or more compounds (B) selected from the group consisting of melamine or a derivative thereof. ~ 0.35 mol is preferred. When the amount of the compound represented by the general formula (l) is less than 0.001 mol, the effect of suppressing the slump loss is small. In addition, if it exceeds 0.5 mol, it may be difficult to control the reaction,
Furthermore, it is economically disadvantageous.

From the group consisting of melamine or its derivatives
As the selected one or more compounds (B),
General formula (11)Where X₁~ X₆: H, CH₂OH or CH₂SO
₃Y  Y: alkali metal, alkaline earth metal, ammonium,
Compounds represented by amines and substituted amines, that is, melamine and methylol group-containing
Use melamine, sulfomethyl-containing melamine, etc.
Can be. In the case of sulfomethyl group-containing melamine,
Salts can also be used. As the salts, inorganic salts,
That is, alkalis such as potassium, sodium, magnesium, etc.
Limetal salts or alkaline earth metal salts, or organic salts
, Ie, ammonium salts, monoethanol salts, dieta
Knol salts and the like can also be used.

Aminobenzenesulfonic acid or derivatives thereof
Or alkylaminobenzenesulfonic acid or its
One or more selected from the group consisting of derivatives of
As the compound (C), the compound represented by the general formula (1111)Where X₇~ X₈: H, CH₂OH or CH₂SO
₃Y  Y: alkali metal, alkaline earth metal, ammonium,
Amine, substituted amine R₃: H or an alkyl group having 1 to 6 carbon atoms X₉: H, alkali metal, alkaline earth metal, ammonium
, Amines, and substituted amines, ie, sulfanilic acid, methanic acid,
Aminobenzenesulfonic acids such as lutanic acid, or
Can be used. As the salts, the general formula
Similarly to (11), inorganic salts and organic salts thereof may be used.
Can be. Among them, sulfanilic acid and metanic acid
And their salts are preferred both in terms of economy and reactivity.

Polyoxyalkylene monoamine and form
As other monomer (D) capable of co-condensing aldehyde
Is the general formula (IV)Where X₁₀: H, sulfone group or alkali thereof
Metals, alkaline earth metals, ammonium salts, amine salts,
Substituted amine salt, CH₂OH or CH₂SO₃Y  Y: alkali metal, alkaline earth metal, ammonium,
Amine, substituted amine R₄: A compound represented by H or an alkyl group having 1 to 6 carbon atoms, that is, phenol or cresol;
pt-butylphenol, pt-amylphenol
Alkyl phenols or their sulfonic acids
Alternatively, sulfonic acid salts and the like can be used. With salt
In the same manner as in the general formula (11), the inorganic salts and organic
Salts can also be used. Among them, phenol,
Alternatively, phenolsulfonic acid and its salts are economically
It is also preferable from the viewpoint of reactivity.

Furthermore, the general formula (V) Here, X _{11 to} X ₁₄ : H, CH ₂ OH or CH ₂
SO ₃ Y Y: alkali metal, alkaline earth metal, ammonium,
Compounds represented by amines and substituted amines, that is, urea, urea containing a methylol group, and urea containing a sulfomethyl group can also be used. In the case of a sulfomethyl group-containing urea, inorganic salts and organic salts thereof can be used as in the case of the general formula (11).

As the compound (E) for forming a sulfone group, known sulfonating agents such as fuming sulfuric acid, sodium sulfite, sodium bisulfite, sodium pyrosulfite, sulfur dioxide and the like can be used. These sulfonating agents may be used in advance for introducing a sulfomethyl group into a raw material corresponding to the general formula (11), the general formula (11), the general formula (IV), or the general formula (V), Acting during or after the synthesis of the cocondensate with formaldehyde,
A sulfomethyl group may be directly introduced into the cocondensate.

The method for introducing a sulfomethyl group into melamine can be carried out by a known method. That is, it can be introduced by adding and condensing melamine with formaldehyde to obtain methylol melamine, then reacting with a sulfonating agent, and replacing with a hydroxyl group. It is known that 6 mol of formaldehyde is addition-condensed as methylol group to 1 mol of melamine. In the present invention, since 2 moles of methylol groups are likely to be used for cocondensation, sulfomethyl groups can be introduced into the remaining 4 moles of methylol groups at the maximum. Considering the economic aspect and the flow effect of the obtained co-condensate, the amount of sulfomethyl group to be introduced is preferably 0.3 to 4 mol, more preferably 0.5 to 2 mol. The same applies to the case where a sulfomethyl group is introduced into sulfanilic acid or metanic acid.
The introduction amount is preferably 0.3 to 2 mol per mol, more preferably 0.5 to 1.5 mol. Further, the same applies to the case where a sulfomethyl group is introduced into phenol. The amount of introduction is preferably from 0.3 to 2 mol, more preferably from 0.5 to 1.5 mol, per mol of phenol. Further, the same applies to the case where a sulfomethyl group is introduced into urea, and the amount of introduction is preferably from 0.3 to 2 mol, more preferably from 0.5 to 1.5 per mol of urea.
Molar is preferred.

The formaldehyde used in synthesizing these formaldehyde cocondensates is usually 3
A concentration of 0 to 60 wt% can be used. Further, if necessary, paraform can be used in combination. The amount of formaldehyde used is selected from the group consisting of one or more compounds (B) selected from the group consisting of melamine or a derivative thereof, aminobenzenesulfonic acid or a derivative thereof, or alkylaminobenzenesulfonic acid or a derivative thereof. It is preferable to use 0.1 to 6 times the total mole number of the compound (C) or the other monomer (D) capable of cocondensing with polyoxyalkylene monoamine and formaldehyde. In consideration of economy, ease of the condensation reaction, and the like, it is more preferable to use 0.5 to 4 moles.
The formaldehyde co-condensation reaction is carried out by an ordinary method in the range of pH 4 to 12, that is, from a weakly acidic region to a basic region.
A pH of 4 or less is not preferable because the reaction cannot be controlled, for example, the condensation reaction may proceed rapidly and cause gelation. Regarding the order of addition of formaldehyde, the reaction may be carried out in advance by charging the reactor or by dropping formalin.

The composition of the compound constituting the admixture in the present invention is important. That is, one or two or more compounds selected from the group consisting of polyoxyalkylene monoamine (A): melamine or a derivative thereof (B): aminobenzenesulfonic acid or a derivative thereof, or alkylaminobenzenesulfonic acid or a derivative thereof The molar ratio of one or more compounds selected from the group (C): polyoxyalkylene monoamine and another monomer capable of co-condensing formaldehyde (D): compound (E) generating a sulfone group is ( 0.001-0.5):
1: (0.05-5): (0.01-5): (0-6)
It is preferred that More preferably, (0.00
5-0.5): 1: (0.05-2) :( 0.01-
2): (0 to 4) is preferable. Still more preferably, (0.005-0.35): 1: (0.1-1):
(0.01-0.5): (0-2) is more preferable.

With regard to the method of using the cement admixture of the present invention, it may be used alone, but one or more other known cement water reducing agents, ie, AE water reducing agent, high performance water reducing agent, high performance AE water reducing agent It can also be used in combination with.
Other known cement water reducing agents include, for example, salts of polycondensates of β-naphthalenesulfonic acid formaldehyde (hereinafter referred to as naphthalene-based), salts of polycondensates of melaminesulfonic acid formaldehyde (hereinafter referred to as melamine-based), lignin sulfone Acid salt, polycarboxylic acid type, polystyrene sulfonate, salt of highly condensed aromatic aminosulfonic acid (hereinafter referred to as aminosulfonic acid type), oxycarboxylic acid salt, condensate obtained by introducing polyethylene glycol chain into aromatic compound , Polyoxyethylene alkyl phenyl ether, poly (meth) acrylate, polyoxyethylene alkyl ether sulfate, copolymer salt of (meth) acrylic acid and vinyl monomer, nonylphenol condensate ethylene oxide adduct, polyethylene polyamine and alkylene Oxide addition polymerization Etc. The.

As to the method of using the admixture of the present invention, other known cement admixtures such as an air entrainer, an antifoaming agent, a setting accelerator, a setting retarder, a rust preventive, a preservative, a waterproofing agent, and a strength enhancer. It can be used in combination with an agent, a separation reducing agent and the like.
In addition, the method of use is usually mixed in kneading water and added to the cement composition.However, the method of adding the cement composition at once or adding it separately at the time of preparing the cement composition, the method of adding the cement composition after kneading, Any method such as the method of adding may be used. The cement admixture according to the present invention varies depending on the composition and use of the cement composition, but is usually 0.01 to 5.0% by weight, preferably 0.1% by weight, based on the solid content of the cement.
It is used in a proportion of from 0.5 to 3.0% by weight. The amount used is 0.
If it is less than 01% by weight, the dispersion fluidity tends to decrease, and the effect of preventing slump loss tends to decrease. Conversely, if it exceeds 5.0% by weight, it tends to cause material separation, making it difficult to obtain a homogeneous cured product, and is economically disadvantageous, which is not preferable.

The cement admixture of the present invention can be applied to concrete and mortar prepared using various portland cements, fly ash cements, blast furnace cements, silica cements, various types of mixed cements and the like. Further, the present invention can be applied to concrete containing silica fume, blast furnace slag, limestone fine powder and the like. Also,
It is also applicable to hydraulic substances such as gypsum.

The reason why the cement admixture of the present invention exhibits an excellent flow effect, a slump loss suppressing effect and a material separation resistance without showing a setting delay is not clear, but is presumed as follows. That is, since the cement admixture of the present invention has a sulfone group in the molecule similarly to the conventional high performance water reducing agent, the dispersibility of the cement particles is enhanced by the electric repulsion. Further, when the cement admixture of the present invention is adsorbed on the cement particles, it is considered that the polyoxyalkylene group in the molecule extends to the outside of the cement particles. A hydration layer is formed around the polyoxyalkylene group extending outward, and it is thought that the steric hindrance effect accompanying the hydration layer maintains the dispersibility of the cement particles for a long time and suppresses slump loss. Furthermore, unlike conventional sustained-release high-performance water reducers, polycarboxylic acid-based water reducers, and alkali-hydrolysis-type water reducers, there is no calcium ion and a high chelating ability carboxyl group in the molecule. It is presumed that it does not show sex. Therefore, the admixture of the present invention has excellent dispersion performance,
It is presumed to have both the effect of suppressing slump loss and the resistance to material separation. The cement admixture of the present invention will be described in more detail in the following examples, but the present invention is not limited thereto. All percentages and parts described below as units of numerical values are% by weight or parts by weight unless otherwise specified.

[0026]

【Example】

Table 1 shows the physical properties of the polyoxyalkylene monoamines used in the present invention. As a representative polyoxyalkylene monoamine, JEFFAMINE M series manufactured by Sun Techno Chemical Co., Ltd. was used. When these compounds are described below, each of them is simply referred to as M-60.
0, M-1000, M-2005, M-2070, M-
Described as 3000.

[0027]

[Table 1] * 1 PO / EO is the molar ratio of propylene oxide to ethylene oxide contained in the molecule. * 2 The molecular weight is the weight average molecular weight.

Production Example 1 1.0 mol (126 parts) of melamine, 5.0 mol (405.4 parts) of 37% formalin, and 430 parts of water were mixed with a stirrer, a thermometer, a reflux tube and a dropping funnel. The mixture was charged into a one-necked flask and mixed with stirring. After the temperature was raised to 65 ° C., 1.0 mol (173 parts) of sulfanilic acid was added, and the pH was rapidly increased to 11.5 with a 25% aqueous sodium hydroxide solution.
And reacted at 65 ° C. for 1 hour. To this, 0.2 mol (12 parts) of urea was added and reacted at 70 ° C. for 1 hour. Next, 250 parts of water was added, and at the same time, the mixture was cooled to 45 ° C., and then 0.2 mol (18.8 parts) of phenol was added thereto over 30 minutes using a dropping funnel. After completion of charging, 60 ° C
For 1 hour. Subsequently, M-1000 is set to 0.03
Mole (30 parts) was charged and reacted at 60 ° C. for 1 hour.
Thereafter, the pH was adjusted to 6.0 with 40% sulfuric acid, the temperature was raised to 65 ° C, and the reaction was performed. When the viscosity of the reaction solution reached 35 cp / 25 ° C, the reaction was stopped by neutralizing with a 25% aqueous sodium hydroxide solution. To give a product of 30 cp / 25 ° C. The obtained product was designated as cocondensate 1. Table 2 shows the composition and physical properties.

Production Example 2 780 parts of water, 4.0 mol of 37% formalin (324.3)
Was charged into a four-necked flask equipped with a stirrer, a thermometer, and a reflux tube, followed by stirring and mixing. In this flask, 1.0 mol (126 parts) of melamine and 0.5 mol (30 parts) of urea were added.
Parts), 0.8 mol of sulfanilic acid (138.4 parts), M
-2070 was added under stirring at 0.06 mol (120 parts). This was heated to 50 ° C., and adjusted to pH 11 with a 25% aqueous sodium hydroxide solution. The temperature was further raised to 75 ° C, the reaction was continued at 75 ° C for 2 hours, and then cooled to 60 ° C. Next, the pH was adjusted to 6.0 with 40% sulfuric acid, and the reaction was proceeded at 60 ° C. When the viscosity of the reaction solution reached 30 cp / 25 ° C, the reaction was neutralized with a 25% aqueous sodium hydroxide solution to stop the reaction. / 25 ° C. The obtained product was designated as cocondensate 2. Table 2 shows the composition and physical properties.

Production Example 3 Water 400 parts, 37% formaldehyde 2.5 mol (20
2.7 parts) was charged into a four-necked flask (A) equipped with a stirrer, a thermometer, and a reflux tube, and stirred and mixed. In this flask (A), 1.0 mol (126 parts) of melamine, M-6
00 was added under stirring 0.3 mol (180 parts). This was heated to 70 ° C., and after confirming that it became a transparent liquid, it was adjusted to pH 11 with a 25% aqueous sodium hydroxide solution and reacted at 70 ° C. for 1 hour. Next, the mixture is cooled to 55 ° C., and anhydrous sodium bisulfite 0.4 mol (41.6 parts)
Was added. Although the internal temperature increased by the addition of anhydrous sodium bisulfite, the temperature was further increased to 80 ° C. The reaction was continued at 80 ° C., and after confirming that free sulfite ions had disappeared, the mixture was cooled to 60 ° C. Similarly, water 300
Parts, 2.0 mol of 37% formaldehyde (162.2
Was charged into a four-necked flask (B) equipped with a stirrer, a thermometer, a reflux tube, and a dropping funnel, mixed with stirring, and adjusted to pH 8 with a 25% aqueous sodium hydroxide solution. 0.6 mol (103.8 parts) of sulfanilic acid in this flask (B)
Is added under stirring. This was heated to 70 ° C.
The mixture was adjusted to pH 11 with a 5% aqueous sodium hydroxide solution, reacted at 70 ° C. for 1 hour, and then cooled to 50 ° C. further,
0.4 mol (37.6 parts) of phenol was added through a dropping funnel to 3 parts.
It was charged over 0 minutes and reacted at 60 ° C. for 1 hour. Next, the contents of the flasks (A) and (B) are charged into a four-necked flask (C) equipped with a stirrer, a thermometer, and a reflux tube, and mixed with stirring. The flask (C) was adjusted to pH 6.0 with 40% sulfuric acid, and the reaction was allowed to proceed at 60 ° C. When the viscosity of the reaction solution reached 80 cp / 25 ° C, the reaction was neutralized with a 25% aqueous sodium hydroxide solution to carry out the reaction. Stop, 70 cp / 2
A product at 5 ° C. was obtained. The product obtained is co-condensate 3
And Table 2 shows the composition and physical properties.

Production Example 4 530 parts of water and 4.0 mol of 37% formaldehyde (32
(4.3 parts) was charged into a four-necked flask equipped with a stirrer, a thermometer, and a reflux tube, and mixed by stirring. Further, 1.0 mol (126 parts) of melamine, 0.4 mol (69.2 parts) of sulfanilic acid, 0.2 mol (12 parts) of urea, and 0.6 mol (114 parts) of sodium pyrosulfite were stirred. Was added. This was heated to 50 ° C., adjusted to pH 11.0 with a 25% aqueous sodium hydroxide solution, and further reacted at 75 ° C. After confirming that free sulfite ions had disappeared, the mixture was cooled to 60 ° C., and 0.05 mol (50 parts) of M-1000 was added. Next, the pH was adjusted to 6.0 with 40% sulfuric acid, the reaction was advanced at 60 ° C., and the viscosity of the reaction solution was 120 cp.
When the temperature reached / 25 ° C, the reaction was stopped by neutralizing with a 25% aqueous sodium hydroxide solution to obtain a product of 110 cp / 25 ° C. The obtained product was designated as co-condensate 4.
Table 2 shows the composition and physical properties.

Production Example 5 Co-condensation was attempted in the same manner as in Production Example 1, except that the composition of the compound and the reaction termination viscosity were changed as shown in Table 2. As a result, a co-condensate 5 was obtained.

Production Example 6 Co-condensation was attempted in the same manner as in Production Example 2, except that the composition of the compound and the reaction termination viscosity were changed as shown in Table 2. As a result, a co-condensate 6 was obtained.

Production Example 7 Co-condensation was attempted in the same manner as in Production Example 3 except that the composition of the compound and the reaction termination viscosity were changed as shown in Table 2. As a result, a co-condensate 7 was obtained.

Production Example 8 Co-condensation was attempted in the same manner as in Production Example 1 except that the composition of the compound and the reaction termination viscosity were changed as shown in Table 2. As a result, a co-condensate 8 was obtained.

Production Examples 9 to 10 Co-condensation was attempted in the same manner as in Production Example 1 except that the composition of the compound and the reaction termination viscosity were changed as shown in Table 2. As a result, co-condensates 9 to 10 were obtained.

Production Example 11 Co-condensation was attempted in the same manner as in Production Example 2 except that the composition of the compound and the reaction termination viscosity were changed as shown in Table 2. As a result, a co-condensate 11 was obtained.

[0038]

[Table 2]

[0039]

[Table 3] Formulation for concrete test Materials for concrete kneading Cement: Three kinds of ordinary Portland cement (Mitsubishi Materials Corporation, Chichibu Onoda Corporation, Tokuyama Corporation)
Specific gravity = 3.16 Fine aggregate: Weathered granite sand from Irino, Kawachi-cho, Kamo-gun, Hiroshima Prefecture
Specific gravity = 2.57 Coarse aggregate: Hard sandstone crushed stone from ishiishi-shaped wall stone in Shimonoseki-shi, Yamaguchi Prefecture Crushed stone 5: Crushed stone 6 = 1: 1: 1 Specific gravity = 2.69

Example 1 Using a 50-liter forced biaxial concrete mixer, based on the composition shown in Table 3, the cement, fine aggregate, and the cement obtained in Production Example 1 were adjusted to a kneading amount of 40 liters. Condensate 1 and water were charged, kneaded and mixed for 90 seconds, coarse aggregate was further charged, and kneaded for 3 minutes. A fluidized concrete having a slump flow of 60 cm and an air amount of 3% was prepared. To achieve the target air volume, use the air entrainer Vinsol manufactured by Yamamune Chemical Co., Ltd. if the entrained air volume is insufficient, and use Hokukon Sangyo Co., Ltd. as an antifoaming agent if the air volume is too high. Was adjusted using Derekrite 850. After kneading, the change over time in the slump flow was measured every 30 minutes until 90 minutes. Further, a columnar specimen having a compressive strength of φ10 cm × height 20 cm was prepared, and for 1 day, 7 days, 28 days.
It was measured according to the material age of the day. Regarding the material separation resistance, the degree of movement of the aggregate during slump flow measurement was visually observed, and relative evaluations of ◎, 、, Δ, and × were made. The method for measuring the slump, the amount of air and the compressive strength, and the method for preparing a specimen for compressive strength are all described in Japanese Industrial Standards (JIS-JIS).
A6204). Table 4 shows the results.

Examples 2 to 8 The same operation as in Example 1 was performed except that cocondensates 2 to 8 were used. Table 4 shows the results.

Comparative Examples 1 to 3 The same operation as in Example 1 was performed except that cocondensates 9 to 11 were used. Table 4 shows the results.

Comparative Example 4 M-1000 was simply blended with co-condensate 9 used in Comparative Example 1 so as to have the same composition as co-condensate 1. Using this, the same operation as in Example 1 was performed. Table 4 shows the results.

Comparative Examples 5 to 9 As a water reducing agent for comparison, Merflow 40 (Mitsui Toatsu Chemical Co., Ltd .: melamine) which is a commercially available high-performance water reducing agent,
Mighty 150 (Kao Corporation: naphthalene type), Palic FP200U (Fujisawa Pharmaceutical Co., Ltd .: aminosulfonic acid type), sustained release type Mighty 2000WH which is a high performance AE water reducing agent (Kao Corporation: naphthalene type + The same operation as in the example was performed using Tupole HP-8 (Takemoto Oil & Fats Co., Ltd .: polycarboxylic acid type).
Table 4 shows the results.

[0045]

[Table 4]

[0046]

As is clear from the examples and comparative examples, the cement admixture obtained according to the present invention shows a high flow effect at a low addition amount and a residual flow as compared with the existing cement water reducing agent. It has the characteristics of high rate and excellent daily strength. That is, it has high initial fluidity and excellent slump holding properties without causing hardening delay for cement compositions such as mortar and concrete. Furthermore, it has excellent material separation resistance. Therefore, when the cement admixture obtained by the present invention is used for civil engineering and construction-related works, workability can be significantly improved.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshihiko Tomita 7-1-1, Hikoshimasako-cho, Shimonoseki-shi, Yamaguchi Pref.

Claims (13)

[Claims] 1. A polyoxyalkylene monoamine (A), one or more compounds (B) selected from the group consisting of melamine or a derivative thereof, aminobenzenesulfonic acid or a derivative thereof, or alkylaminobenzenesulfonic acid or a derivative thereof. A cement admixture comprising one or more compounds (C) selected from the group consisting of derivatives and a formaldehyde co-condensate of a polyoxyalkylene monoamine and another monomer (D) capable of formaldehyde co-condensation. 2. One or more compounds (B) selected from the group consisting of polyoxyalkylene monoamines (A), melamine or derivatives thereof, aminobenzenesulfonic acid or derivatives thereof, or alkylaminobenzenesulfonic acids or derivatives thereof. One or more compounds (C) selected from the group consisting of derivatives, other monomers (D) capable of co-condensing polyoxyalkylene monoamine with formaldehyde, and compounds (E) that generate sulfone groups. Cement admixture consisting of formaldehyde co-condensate. 3. The cement admixture according to claim 1, wherein the polyoxyalkylene monoamine (A) is represented by the following general formula (1). General formula (1) R ₁ O— (AO) _m (BO) _n —R ₂ —NH ₂ where R ₁ , R ₂ : alkyl group having 1 to 5 carbon atoms AO, BO: 2 to 5 carbon atoms Oxyalkylene groups AO and BO are block and / or random m, n: an integer of 0 to 300. However, 300 ≧ m + n ≧ 4 4. A group consisting of melamine or a derivative thereof.
One or more compounds (B) selected from
3. The method according to claim 1, wherein the semester is represented by the general formula (11).
Admixture. General formula (11)Where X₁~ X₆: H, CH₂OH or CH₂SO
₃Y  Y: alkali metal, alkaline earth metal, ammonium,
Amine, substituted amine 5. An aminobenzenesulfonic acid or a compound thereof.
Derivatives or alkylaminobenzenesulfonic acids or
Is one or more selected from the group consisting of its derivatives
The above compound (C) is a compound represented by the following general formula (1111)
3. The cement admixture according to claim 1 or claim 2. General formula (Ill)Where X₇~ X₈: H, CH₂OH or CH₂SO
₃Y  Y: alkali metal, alkaline earth metal, ammonium,
Amine, substituted amine R₃: H or an alkyl group having 1 to 6 carbon atoms X₉: H, alkali metal, alkaline earth metal, ammonium
, Amine, substituted amine 6. Another monomer (D) capable of co-condensing polyoxyalkylene monoamine with formaldehyde.
Is a compound selected from the group consisting of phenol or a derivative thereof, and urea or a derivative thereof. 7. The phenol or a derivative thereof, wherein
The cement admixture according to claim 6, which is represented by the following general formula (IV):
Agent. General formula (IV)Where X₁₀: H, sulfone group or alkali thereof
Metals, alkaline earth metals, ammonium salts, amine salts,
Substituted amine salt, CH₂OH or CH₂SO₃Y  Y: alkali metal, alkaline earth metal, ammonium,
Amine, substituted amine R₄: H or an alkyl group having 1 to 6 carbon atoms 8. The cement admixture according to claim 6, wherein the urea or a derivative thereof is represented by the following general formula (V). General formula (V) Here, X _{11 to} X ₁₄ : H, CH ₂ OH or CH ₂
SO ₃ Y Y: alkali metal, alkaline earth metal, ammonium,
Amine, substituted amine 9. A compound (E) which forms a sulfone group
3. The cement admixture according to claim 2, wherein the admixture comprises one or more compounds selected from the group consisting of sodium sulfite, sodium bisulfite, sodium pyrosulfite, fuming sulfuric acid, and sulfur dioxide. 10. The cement admixture according to claim 4, wherein one or more compounds (B) selected from the group consisting of melamine or a derivative thereof are melamine. 11. The compound (C) selected from the group consisting of aminobenzenesulfonic acid or a derivative thereof, or alkylaminobenzenesulfonic acid or a derivative thereof, is sulfanilic acid or metanic acid. The cement admixture according to the above. 12. The cement admixture according to claim 6, wherein the phenol or a derivative thereof is phenol or phenolsulfonic acid. 13. The cement admixture according to claim 6, wherein the urea or a derivative thereof is urea.