JPH09165247A - Cement admixture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cement admixture having excellent fluidizing effect, slump loss-suppressing effect and resistance to material separation without setting retardation. SOLUTION: This cement admixture is composed of a formaldehyde co- condensate of a polyoxyalkylenemonoglycidyl ether expressed by the formula, R1 -O-(AO)m (BO)n -CH2 -CHOCH2 (R1 is a 1-2C alkyl group or phenyl group, AO and BO are each a 2-5C oxyalkylene group and bonded in a block and/or random state, (m) and (n) are each an integer of 0-100, 100>=(m+n)>=4), a monomer capable of addition-reacting with the polyoxyalkylenemonoglycidyl ether and a compound generating 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. As typical ones, salts of β-naphthalene sulfonic acid formaldehyde high condensation product, melamine sulfonic acid formaldehyde condensation product, lignin sulfonate, amino sulfonic acid condensation product salt, oxycarboxylic acid, etc. are known. . 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. Also, due to reduced fluidity, the compact may not be sufficiently compacted in the mold and a defective portion may be generated.

Therefore, various water reducing agents have been developed in the past in order to suppress slump loss. 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 retaining slump due to steric hindrance of the molecular chain, a polyalkylene glycol monoester monomer having an unsaturated bond and a (meth) acrylic acid monomer and / or an unsaturated dicarboxylic acid monomer And copolymers (Japanese Patent Publication No. 59-18338, Japanese Patent Publication No. 2-7897, Japanese Patent Publication No. 2-7898, Japanese Patent Publication No. 2-7901, Japanese Patent Publication No. 2-8983, Japanese Patent Publication No. 2-11542. JP-B, JP-B-5-11057, JP-B-6-88817), and the like, and water-soluble vinyl copolymers (these are collectively referred to as polycarboxylic acid-based copolymers). 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.

However, while these compounds show excellent flow effect, they have various problems. First,
In the case of sustained-release high-performance water reducing agents that work with alkali in concrete and water-soluble vinyl copolymers that are alkali-hydrolyzed to replenish functional groups and suppress slump loss, carboxyl groups are contained in the compound. Appears over time. This carboxyl group has a strong binding force with calcium ions. Therefore, these compounds trap calcium ions in the cement, and when the amount of addition is large, there is a problem that the setting delay becomes large and the process cannot proceed to the next operation.

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)
Since copolymerization is carried out using acrylic acid-based monomers and / or unsaturated dicarboxylic acid-based monomers, these compounds have a carboxyl group in the molecule. However, there is a problem that is increased. 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 made extensive studies in order to solve these problems. As a result, a compound having a specific molecular structure does not cause a significant retardation of curing and has an excellent dispersion effect. The present invention has been accomplished by finding that the slump retention effect is exhibited, and further, the material separation resistance is remarkable.

That is, the present invention provides a polyoxyalkylene monoglycidyl ether (A) represented by the following general formula (1).
And a cement admixture comprising a formaldehyde co-condensate of a monomer (B) capable of addition reaction with a polyoxyalkylene monoglycidyl ether (A) and a compound (C) forming a sulfone group. General formula (l) Here, R ₁ : an alkyl group having 1 to 20 carbon atoms, a phenyl group AO, BO: an oxyalkylene group having 2 to 5 carbon atoms AO and BO are block and / or random m, n: an integer of 0 to 100. However, 100 ≧ m + n ≧ 4

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
What is used in the present invention is the following general formula (1) polyoxyalkylene monoglycidyl ether (A). General formula (l) Here, R ₁ : an alkyl group having 1 to 20 carbon atoms, a phenyl group AO, BO: an oxyalkylene group having 2 to 5 carbon atoms AO and BO are block and / or random m, n: an integer of 0 to 100. However, 100 ≧ m + n ≧ 4 The compound represented by the polyoxyalkylene monoglycidyl ether (A) of the general formula (l) includes phenol polyoxyethylene glycidyl ether, phenol polyoxypropylene glycidyl ether, and phenol polyoxyethyleneoxypropylene glycidyl. Polyoxyalkylene glycidyl ethers such as ether, lauryl alcohol polyoxyethylene glycidyl ether, lauryl alcohol polyoxypropylene glycidyl ether, and lauryl alcohol polyoxyethylene oxypropylene glycidyl ether.

The polyoxyalkylene monoglycidyl ether (A) of the general formula (1) has 2 to 5 carbon atoms in the oxyalkylene group. If the number of carbon atoms exceeds 5, the water solubility decreases, and not only cocondensation becomes difficult, but also an excellent flow effect cannot be obtained. The oxyalkylene group may be of one type, but may be of a type in which two or more types of oxyalkylene groups are bonded in a block or random manner. The number of repeating units is 4 to 100, and more preferably 7 to 70. If this repeating unit is less than 4,
In some cases, the resulting cement admixture does not have a sufficient flow effect and the slump loss suppression effect is not sufficient. Also,
If the number exceeds 100, the cocondensation may not proceed well.

The alkyl moiety of R ₁ in the general formula (1) has 1 to 20 carbon atoms. When the number of carbon atoms exceeds 20, even if a formaldehyde cocondensate is produced and used as a cement admixture, a sufficient flow effect may not be obtained, probably because the hydrophobic portion is large.

The compound represented by the general formula (l) may be added at any step in the reaction step for producing the cement admixture of the present invention, but the general formula (ll) and / or the general formula (lll) ) And / or the general formula (IV) and / or the step of charging the compound represented by the general formula (V) is preferable.

The compound represented by the general formula (1) is 1
More than one type can be used in combination. Furthermore, the addition amount thereof is preferably 0.005 to 0.5 mol, more preferably 1 to 5 mol of the monomer (B) capable of addition reaction with the polyoxyalkylene monoglycidyl ether (A). , 0.01 to 0.35 mol is preferable. When the amount of the compound represented by the general formula (1) is less than 0.005 mol, the slump loss suppressing effect is little exhibited. On the other hand, if it exceeds 0.5 mol, it may be difficult to control the reaction, which is economically disadvantageous.

The monomer (B) capable of addition reaction with polyoxyalkylene monoglycidyl ether is represented by the general formula (11) Here, X ₁ , X ₂ , X ₃ : H, CH ₂ OH or CH
₂ SO ₃ Y Y: alkali metal, alkaline earth metal, ammonium,
Compounds represented by amino groups and substituted amino groups, that is, melamine, methylol group-containing melamine, sulfomethyl group-containing melamine, and the like can be used. In the case of sulphomethyl group-containing melamine, salts thereof can also be used. As the salts, inorganic salts,
That is, alkali metal salts or alkaline earth metal salts of potassium, sodium, magnesium or the like, or organic salts, that is, ammonium salts, monoethanolamine salts, diethanolamine salts and the like can also be used.

Further, in addition, as a general formula (lll) Here, X ₄ : H, CH ₂ OH or CH ₂ SO ₃ Y,
Sulfone group or its alkali metal salt, alkaline earth metal salt, ammonium salt, amine group, substituted amine group Y: alkali metal, alkaline earth metal, ammonium,
Amino group, substituted amino group R ₃ : Compound represented by H or alkyl group having 1 to 6 carbon atoms, that is, phenol, cresol, p
Alkylphenols such as -t-butylphenol and pt-amylphenol, sulfonic acids or salts of sulfonic acids thereof, methylol group-containing phenols, sulfomethyl group-containing phenols, or salts thereof can also be used. As the salt, an inorganic salt or an organic salt thereof can be used as in the case of the general formula (11). Among them, phenol, methylol group-containing phenol, sulfomethyl group-containing phenol, or phenolsulfonic acid and salts thereof are preferable in terms of economical efficiency and reactivity.

Further, the general formula (IV) Here, X ₅ , X ₆ : H, CH ₂ OH or CH ₂ SO
₃ Y Y: alkali metal, alkaline earth metal, ammonium,
A compound represented by an amino group or a substituted amino group, that is, urea, methylol group-containing urea, or sulfomethyl group-containing urea can also be used. In the case of sulfomethyl group-containing urea, inorganic salts and organic salts thereof can be used as in the case of the general formula (11).

Further, the general formula (V) Here, X ₇ : H, an alkali metal, an alkaline earth metal,
Ammonium, an amino group, a substituted amino group R ₄ : H or a compound represented by an alkyl group having 1 to 6 carbon atoms, that is, an aminobenzenesulfonic acid such as sulfanilic acid, methanic acid, ortanic acid, or a salt thereof can be used. . As the salt, an inorganic salt or an organic salt thereof can be used as in the case of the general formula (IV). Among them, sulfanilic acid, metanic acid and salts thereof are preferable from the viewpoint of economy and reactivity.

In the present invention, the general formula (11),
One or more kinds of monomers represented by the general formula (111), the general formula (IV) and the general formula (V) can be used in combination. However, the use of the general formula (11) is economical and also reactive. Is also preferable.

Known sulfonating agents such as sodium sulfite, sodium bisulfite, sodium pyrosulfite, sulfur dioxide, fuming sulfuric acid and the like can be used as the compound generating a sulfone group.

These sulfonating agents have previously been represented by the general formula (l
l), the general formula (lll) and the general formula (lv) may be used when introducing a sulfomethyl group into the corresponding raw material, or may be used after synthesizing the cocondensate with formaldehyde and then acting A sulfomethyl group may be directly introduced into.

The sulfomethyl group can be introduced into melamine by a known method. That is, it can be introduced by addition-condensing melamine with formaldehyde to obtain methylolmelamine, and then actuating a sulfonating agent to replace it 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 economical aspect and the flow effect of the obtained cocondensate, the introduction amount of the sulfomethyl group is preferably 0.3 to 4 mol, and more preferably 0.5 to 2 mol. The same applies to the case where a sulfomethyl group is introduced into phenol, and the amount introduced is preferably 0.3 to 2 mol, and more preferably 0.5 to 1.5 mol, per mol of phenol. The same applies to the case where a sulfomethyl group is introduced into urea, and the amount introduced is preferably 0.3 to 2 mol, and more preferably 0.5 to 1.5 mol, per 1 mol of urea.

The formaldehyde used for synthesizing these formaldehyde cocondensates is usually 3
Those having a concentration of 0 to 60% by weight can be used. Further, if necessary, paraform can be used in combination. The amount of formaldehyde used is preferably 1 to 6 times the total number of moles of the monomer (B) capable of addition reaction with the polyoxyalkylene monoglycidyl ether (A). In consideration of economy, ease of the condensation reaction, and the like, it is more preferable to use 1.5 to 4 moles.

The formaldehyde co-condensation reaction is carried out at pH 4-1.
In the range of 2, the so-called weakly acidic region to the basic region is usually used. If the pH is less than 4, it is difficult to control the reaction, for example, the condensation reaction may rapidly proceed and gel. In addition, the formaldehyde may be added in advance in the reaction apparatus, or may be reacted by dropping formalin during the reaction.

The composition of the compound constituting the admixture in the present invention is important. That is, the molar ratio of polyoxyalkylene monoglycidyl ether (A): polyoxyalkylene monoglycidyl ether (A) capable of addition reaction with monomer (B): compound forming a sulfone group (C): formaldehyde is (0.005-0.5): 1:
(0.3-4): It is preferable that it is (1-6). More preferably, (0.01-0.35): 1: (0.
5-2): (1.5 to 4) is preferable.

Next, an example of a specific method for producing the admixture in the present invention is shown below, but the present invention is not limited to this. . Example 1 Formaldehyde and water were mixed with a stirrer, thermometer, reflux tube,
A 4-necked flask equipped with a dropping funnel is charged, and then the compound represented by the general formula (11) is added. Reactor temperature 6
After raising the temperature to 0 to 90 ° C., the reaction is carried out under basic conditions for 0.5 to 2 hours. Next, the compounds represented by the general formula (1), the general formula (IV) and the general formula (V) were charged, and further 60 to 9
The reaction is carried out at 0 ° C for 0.5 to 2 hours, then cooled to 30 to 50 ° C, and the compound represented by the general formula (lll) is added dropwise from the dropping funnel over 10 to 120 minutes. 50-90 ° C
After the reaction for 0.5 to 2 hours, the compound (C) that forms a sulfone group is added, and the reaction is performed at 60 to 90 ° C for 0.5 to 3 hours. Further, the inside of the system is made weakly acidic, and the reaction proceeds at 50 to 80 ° C. until the viscosity of the solution reaches a predetermined value. When the viscosity of the solution reaches a predetermined value, it is neutralized to stop the reaction. The predetermined viscosity for stopping the reaction varies depending on the nonvolatile content of the solution. When the nonvolatile content is 35%, the value measured by a B-type viscometer is preferably 10 to 500 cp / 25 ° C.
5 to 300 cp / 25 ° C is more preferable. When the viscosity is out of this range, even if the obtained cocondensate is added to the cement composition, the fluidizing effect and the slump loss suppressing effect are not sufficiently exhibited, which is not preferable.

The compound represented by the general formula (l) can be added in all the steps of the reaction step for producing the cement admixture of the present invention, but the general formula (ll) and / or the general formula (l) and / or general formula (LV)
And / or it is preferable to add the compound represented by the general formula (V) to the step after charging. That is, the compound represented by the general formula (11) may be added during the temperature rise, during or after the reaction under the basic condition, and before or after the charging of the compound (C) which forms a sulfo group. ,
You may add just before and immediately after adjusting pH to a weakly acidic area | region. Further, for the purpose of cooling, the charged water may be divided into the respective steps, or the addition of each compound may be divided and added. Furthermore, you may change the addition order of each compound.

Specific Example 2 Compounds represented by the general formula (1), the general formula (11), the general formula (IV) and the general formula (V), formaldehyde, water,
And the compound (C) which produces | generates a sulfone group is prepared in a 4-neck flask equipped with a stirrer, a thermometer, and a reflux tube, and is made to react under basicity at 60-90 degreeC for 0.5-5 hours. Furthermore, the inside of the system is set to a weakly acidic region and the reaction is performed at 40 to 80 ° C. for 0.5 to 10 hours. When the viscosity of the solution reaches a predetermined value, it is neutralized to stop the reaction. The predetermined viscosity for stopping the reaction is the same as in Specific Example 1. Further, as in the case of Example 1, the compound represented by the general formula (1) may be charged any time as long as it is before the step immediately after changing the liquid property in the system to weakly acidic.

The cement admixture of the present invention can be used in combination with other conventionally known water reducing agents, AE water reducing agents, high performance water reducing agents, high performance AE water reducing agents, and superplasticizers. That is, β-naphthalene sulfonic acid formaldehyde high condensate salt, melamine sulfonic acid formaldehyde condensate salt, amino sulfonic acid condensate salt, lignin sulfonic acid salt, oxycarboxylic acid, polycarboxylic acid type water reducing agent, alkali hydrolysis It can be used in combination with a type water reducing agent, a sustained release high performance water reducing agent, and the like.

Regarding the method of using the admixture of the present invention, other known cement admixtures such as air entraining agent, defoaming agent, setting accelerator, setting retarder, rust preventive, antiseptic, waterproofing agent, strength accelerator Combination with agents and the like is also possible. 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 admixture according to the present invention varies depending on the formulation and the use of the cement composition, but is usually 0.01 to 0.01 in terms of solid content relative to cement.
It is used in a proportion of 5.0% by weight, preferably 0.05 to 3.0% by weight. If the amount used is less than 0.01% by weight,
This is not preferred because the dispersion fluidity tends to decrease and the effect of preventing slump loss tends to decrease. On the other hand, 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.

The cement admixture according to the present invention can be applied to concrete and mortar prepared by using various Portland cement, fly ash cement, blast furnace cement, silica cement, various mixed cements and the like. Furthermore, the present invention can be applied to concrete containing silica fume, blast furnace slag, limestone fine powder and the like.

The reason why the cement admixture of the present invention exhibits excellent flow effect, slump loss suppressing effect, and material separation resistance without showing retardation of setting is not clear, but it is presumed as follows. That is, since the admixture of the present invention has a sulfone group in the molecule similarly to the conventional high-performance water reducing agent,
The electric repulsion enhances the dispersibility of the cement particles. Moreover, when the admixture of the present invention is adsorbed on the cement particles, it is considered that the polyoxyalkylene group contained in the molecule extends outside the cement particles. It is considered that a hydration layer is formed around the polyoxyalkylene group extending to the outside, and the steric hindrance effect associated therewith holds the dispersibility of the cement particles for a long time and suppresses slump loss. Furthermore, as in the conventional sustained-release high-performance water reducing agent, polycarboxylic acid-based water reducing agent, and alkali hydrolysis-type water reducing agent, C is contained in the molecule.
Since it does not have an a ion and a carboxyl group having a high chelating ability, it is not expected to exhibit a setting retardation. therefore,
The admixture of the present invention has excellent dispersion performance, slump loss suppressing effect, and material separation resistance.

The admixture of the present invention will be described in more detail in the following examples, but the present invention is not limited thereto. In addition, all percentages or parts described below as units of numerical values are% by weight or parts by weight unless otherwise specified. Further, the portion described as (EO) _n means that there are n repeating portions of ethylene glycol.

[0034]

【Example】

Production Example 1 0.52 mol (65.5 parts) of melamine, 3.0 mol (243.2 parts) of 37% formalin, and 250.0 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., the pH was adjusted to 11.5 with a 25% aqueous sodium hydroxide solution.
The reaction was performed at 65 ° C. for 1 hour. Add 0.2 mole of urea (1
2.0 parts) and 0.15 mol of sulfanic acid (26.0).
Was added and the mixture was further reacted at 70 ° C. for 1 hour. Next, 131.4 parts of water was added, and at the same time, the mixture was cooled to 45 ° C. Then, 0.13 mol (12.2 parts) of phenol was added thereto over 30 minutes using a dropping funnel. After completion of the charging, the reaction was carried out at 60 ° C. for 1 hour. Subsequently, lauryl alcohol (E
O) Denacol EX-1 which is ₁₅ glycidyl ether
71 (manufactured by Nagase Kasei Kogyo Co., Ltd.) at 0.03 mol (2
7.1 parts), anhydrous sodium bisulfite 0.53 mol (5
5.1 parts) and reacted at 80 ° C. for 1 hour. 60
After cooling to 40 ° C., the pH was adjusted to 6.0 with 40% sulfuric acid,
C. and the reaction was carried out, and the viscosity of the reaction solution was 40 cp / 2.
When the temperature reached 5 ° C., the reaction was stopped by neutralization with a 25% aqueous sodium hydroxide solution. The composition and physical properties are shown in Table 1.

Production Example 2 647.8 parts of water, 3.1 mol of 37% formalin (25 mol)
(1.4 parts) was charged into a four-necked flask equipped with a stirrer, a thermometer, and a reflux tube, followed by stirring and mixing. 0.7 mol (88.2 parts) of melamine and 0.1 mol of urea (6.
0 part), 0.2 mol of sulfaninic acid (34.6 parts) and 0.5 mol of sodium pyrosulfite (95.0 parts) were added under stirring. After raising the temperature to 75 ° C. and confirming that a transparent liquid was obtained, 0.13 mol (117.3 parts) of Denacol EX-171 used in Production Example 1 was added, and then 25% sodium hydroxide was added. PH 11 with aqueous solution, 7
The reaction was performed at 5 ° C. for 2 hours. After confirming that free sulfite ions had disappeared, the mixture was cooled to 60 ° C. Then 4
The pH was adjusted to 6.0 with 0% sulfuric acid, the reaction was allowed to proceed at 60 ° C., and when the viscosity of the reaction solution reached 50 cp / 25 ° C., 25%
The reaction was terminated by neutralization with an aqueous sodium hydroxide solution, and the resulting product was used as condensate 2. The composition and physical properties are shown in Table 1.

Production Example 3 352.3 parts of water, 2.8 mol (22%) of 37% formalin
(7.0 parts) was charged into a four-necked flask equipped with a stirrer, a thermometer, and a reflux tube, and mixed by stirring. 1.0 mol (126.0 parts) of melamine is added to the flask with stirring.
This was heated to 70 ° C., and after confirming that it became a transparent liquid, phenol (EO) ₅ glycidyl ether Denacol EX-145 (manufactured by Nagase Chemical Industry Co., Ltd.) 0.1 mol (37 (0.0 parts) The pH was adjusted to 11 with a 25% aqueous sodium hydroxide solution, and the mixture was reacted at 70 ° C for 1 hour. Next, the mixture was cooled to 55 ° C, and anhydrous sodium bisulfite 0.8 (83.2 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. Next, the pH was adjusted to 6.0 with 40% sulfuric acid, the reaction was allowed to proceed at 60 ° C, and when the viscosity of the reaction solution reached 115 cp / 25 ° C, the reaction was neutralized with a 25% aqueous sodium hydroxide solution to stop the reaction. The obtained product was designated as condensate 3. The composition and physical properties are shown in Table 1.

Production Examples 4 to 5 Condensation was tried in the same manner as in Production Example 1 by changing the composition of the compound as shown in Table 1. As a result, condensates 4 to 5 were obtained.

Production Examples 6 to 7 Condensation was attempted in the same manner as in Production Example 2 while changing the composition of the compound as shown in Table 1. As a result, condensates 6 to 7 were obtained.

Production Examples 8 to 9 Condensation was tried by changing the composition of the compound as shown in Table 1 in the same manner as in Production Example 3. As a result, condensates 8 to 9 were obtained.

Production Example 10 Except that the compound represented by the general formula (1) was not used,
Condensation was attempted in the same manner as in Production Example 1 while changing the compound composition as shown in Table 1. As a result, a condensate 10 was obtained.

Production Examples 11 to 12 Using Denacol EX-171 used in Production Example 1, condensation was tried in the same manner as in Production Example 1 by changing the composition of the compound as shown in Table 1. As a result, condensates 11 to 12 were obtained.

[0042]

[Table 1]

Example 1 Using a 50-liter forced twin-screw concrete mixer, based on the composition shown in Table 2, cement, coarse aggregate, and the condensation obtained in Production Example 1 so as to obtain a kneading amount of 40 liters. The substance 1 and water were added, and the mixture was kneaded for 90 seconds, and the coarse aggregate was further added and kneaded for 3 minutes. A highly fluid concrete having a slump of 18 cm and an air volume of 3% was prepared. In order to reach the target air volume, if the entrained air volume is insufficient, use the air entrainer Vinsol manufactured by Yamamune Chemical Co., Ltd.
When the amount of air was too high, it was adjusted using Derekrite 850 manufactured by Hokukon Sangyo Co., Ltd. as an antifoaming agent. After kneading, slump and slump flow with time were measured every 30 minutes until 90 minutes later. The compression strength is φ1
A cylindrical test specimen of 0 cm × 20 cm in height was prepared, and for one day,
It was measured on days 7 and 28. 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. still,
Slump, air volume, setting time and compressive strength measurement method,
In addition, the method of preparing the specimen for compressive strength was all based on Japanese Industrial Standards (JIS-A6204). Table 3 shows the results.

[0044]

[Table 2] W / C: water / cement (% by weight) s / a: fine aggregate / (fine aggregate + coarse aggregate) (volume%) C: cement S: fine aggregate G: coarse aggregate

Cement mixing material for concrete: Three kinds of ordinary Portland cement (Mitsubishi Materials Corporation, Chichibu Onoda Co., Ltd., 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

Examples 2 to 9 The same operation as in Example 1 was carried out except that condensates 2 to 9 were used. Table 3 shows the results.

Comparative Examples 1 to 3 The same operation as in Example 1 was performed except that condensates 10 to 12 were used. Table 3 shows the results.

Comparative Examples 4 to 8 As a comparative water reducing agent, a commercially available high-performance water reducing agent, Melflow 40 (Mitsui Toatsu Chemical Co., Ltd .: melamine type),
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 Example 1 was performed using Tupole HP-8 (Takemoto Oil & Fats Co., Ltd .: polycarboxylic acid system). Table 3 shows the results.

[0049]

[Table 3]

[0050]

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 a high initial fluidity and an excellent slump retention property for a cement composition such as mortar and concrete without causing a hardening delay. Furthermore, the material separation resistance is also excellent. 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 (7)

[Claims] 1. A monomer (B) and a sulfone group capable of undergoing an addition reaction with the polyoxyalkylene monoglycidyl ether (A) and polyoxyalkylene monoglycidyl ether (A) represented by the following general formula (1) are produced. A cement admixture comprising a formaldehyde co-condensate of a compound (C) for General formula (l) Here, R ₁ : an alkyl group having 1 to 20 carbon atoms, a phenyl group AO, BO: an oxyalkylene group having 2 to 5 carbon atoms AO and BO are block and / or random m, n: an integer of 0 to 100. However, 100 ≧ m + n ≧ 4 2. Compound (C) which produces a sulfone group
The cement admixture according to claim 1, wherein the cement admixture comprises one or more compounds selected from the group consisting of sodium sulfite, sodium bisulfite, sodium pyrosulfite, fuming sulfuric acid, and sulfur dioxide. 3. A monomer (B) capable of addition reaction with polyoxyalkylene monoglycidyl ether (A) is melamine or a derivative thereof, phenol or a derivative thereof, urea or a derivative thereof, aminobenzenesulfonic acid or a derivative thereof. Or the cement admixture according to claim 1, which is one or more compounds selected from the group consisting of alkylaminobenzenesulfonic acid and derivatives thereof. 4. The cement admixture according to claim 3, wherein melamine or its derivative is represented by the following general formula (11). General formula (11) General formula (11) Here, X ₁ , X ₂ , X ₃ : H, CH ₂ OH or CH
₂ SO ₃ Y Y: alkali metal, alkaline earth metal, ammonium,
Amino group, substituted amino group 5. The cement admixture according to claim 3, wherein the phenol or its derivative is represented by the following general formula (111). General formula (Ill) Here, X ₄ : H, CH ₂ OH or CH ₂ SO ₃ Y,
Sulfone group or its alkali metal salt, alkaline earth metal salt, ammonium salt, amine group, substituted amine group Y: alkali metal, alkaline earth metal, ammonium,
Amino group, substituted amino group R ₃ : H or an alkyl group having 1 to 6 carbon atoms 6. The cement admixture according to claim 3, wherein the urea or its derivative is represented by the following general formula (IV). General formula (LV) Here, X ₅ , X ₆ : H, CH ₂ OH or CH ₂ SO
₃ Y Y: alkali metal, alkaline earth metal, ammonium,
Amino group substituted amino group 7. The cement admixture according to claim 3, wherein the aminobenzenesulfonic acid or its derivative, or the alkylaminobenzenesulfonic acid or its derivative is represented by the following general formula (V). General formula (V) Here, X ₇ : H, an alkali metal, an alkaline earth metal,
Ammonium, amino group, substituted amino group R ₄ : H or an alkyl group having 1 to 6 carbon atoms