JPH08722B2 - Cement dispersant - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates to a cement dispersant. More specifically, it relates to a cement dispersant for the purpose of improving the fluidity and fluidity retention of hydraulic compositions such as cement paste, mortar and concrete.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
As a cement dispersant used for the purpose of improving the fluidity of a hydraulic composition, a naphthalenesulfonic acid formaldehyde condensate salt (hereinafter referred to as a naphthalene type), a melaminesulfonic acid formaldehyde condensate salt (hereinafter referred to as a melamine type), Polycarboxylic acid salts (hereinafter referred to as polycarboxylic acid type) and the like are used. However, each of them has excellent characteristics, but it has problems.

For example, the polycarboxylic acid type is excellent in dispersibility, but has a problem that the setting delay of concrete is large, and the naphthalene type and melamine type are excellent in dispersibility and curing characteristics, but slump loss (fluidity with time). The current situation is that there is no one satisfying all the properties required as a cement dispersant, and there are some problems.

[0004]

As a result of intensive studies, the inventors of the present invention have clarified the characteristics of various surfactants (including a dispersant) with respect to concrete, and have made clear from the findings. By designing the structure of the dispersant, we have completed a dispersant that has excellent dispersion characteristics and slump retention that cannot be obtained with existing dispersants, and that has a small curing delay.

That is, according to the present invention, one or more selected from aromatic compounds having 4 to 100 mol of an oxyalkylene group having 2 to 3 carbon atoms and a formaldehyde co-condensable substance are selected. Formaldehyde co-condensation product with one or two or more compounds having an average molecular weight of 10,000 to
And a cement dispersant having a sulfonic acid group or a sulfomethyl group in the cocondensate.

More specifically, the present invention provides the following general formulas A and B.
A formaldehyde copolymer of one or more selected from the compounds represented by (a) and one or more selected from the compounds represented by the following general formulas C and D (b): The cement dispersant according to claim 3, wherein the main component is a condensate having an average molecular weight of 10,000 to 30,000.

[0007]

[Chemical 4]

(Wherein R ₁ and R _{2 are} H or an alkyl group having 1 to 9 carbon atoms RO ₁ and RO ₂ ; an oxyalkylene group having 2 to 3 carbon atoms n ₁ and n ₂ ; an integer Z of 4 to 100; ₁ , Z ₂ ; H or SO ₃ X ₁ X ₁ ,; H, which represents a monovalent or divalent metal, an ammonium group, an amino group or a substituted amino group.)

[0009]

[Chemical 5]

(In the formula, R ₃ and R ₄ ; H or an alkyl group having 1 to 6 carbon atoms, X ₂ and X ₃ ; H, an alkali metal salt, an alkaline earth metal salt or an organic salt.) invention cage having an average molecular weight of 20, 000 or less
Formaldehyde co-condensate of naphthalene sulfonic acid formaldehyde condensate or phenol sulfonic acid formaldehyde condensate which is a gomer or polymer (c) and one or more compounds represented by the above general formulas A and B (a). And the average molecular weight is 10,000 to 30,000
4. The cement dispersant according to claim 3 , which is mainly composed of

Furthermore, the present invention provides one or more compounds selected from compounds represented by the following general formula E and compounds represented by the following general formulas F to H (provided that the general formula F
Or a compound represented by G is mandatory) and the a co-condensate with addition condensation with formaldehyde, average molecular weight
Relates to a cement dispersant containing 10,000 to 30,000 as an essential component.

[0012]

[Chemical 6]

(In the formula, RO ₃ ; an oxyalkylene group having 2 to ₃ carbon atoms n ₃ ; an integer of 4 to 100, R ₅ and R ₆ ; H or an alkyl group having 1 to 9 carbon atoms, X ₄ and X ₅ ; H , Sulfone group or its alkali metal salt Y _{1 to} Y ₅ ; H, CH ₂ OH or CH ₂ SO ₃ Z (Z is an alkali metal salt)
Provided that when X ₄ is H, at least one of Y _{1 to} Y ₅ is CH ₂ SO ₃ Z and / or X ₅ is SO ₃ X. ) The formaldehyde co-condensate of the present invention has a three-dimensional molecular structure, which is adsorbed on cement particles to enhance the steric repulsive force, which enhances the dispersive power and the slump retention property. It is presumed that these effects are enhanced by the alkylene group having a graft structure.

In the present invention, as the aromatic compound having 4 to 100 mol of oxyalkylene group having 2 to 3 carbon atoms, oxyalkylene for phenol (including lower alkylphenol), bisphenol, aminobenzene, salicylic acid, benzoic acid and the like is used. Group introduction product and naphthol
(Lower alkylnaphthol), which is an oxyalkylene group-introduced product to aminonaphthalene, etc., and which has a hydroxyl group, an amino group,
Examples thereof include a benzene ring derivative having a carboxyl group, a naphthalene derivative, and aromatic compounds having a sulfone group.

The compound represented by the general formula A is a compound obtained by adding 4 to 100 mol of ethylene oxide or propylene oxide to phenol or an alkylphenol, or a compound obtained by further sulfonation thereof, and the compound represented by the general formula B. Is naphthol or alkylnaphthol to which 4 to 100 mol of ethylene oxide or propylene oxide is added, or sulfonation thereof.

As the alkyl group of the compounds represented by the general formulas A and B, a linear or branched alkyl group having 1 to 9 carbon atoms such as methyl, ethyl, propyl, isopropyl and nonyl is used.

The sulfonated compounds of the general formulas A and B are sulfonic acid or monovalent and divalent metals,
It is a neutralized salt of an ammonium group, an amino group, a substituted amino group and the like. The sulfonation method can be carried out by a general method in which sulfuric acid or fuming sulfuric acid is used in a molar amount of 0.9 to 1.5 times with respect to the oxyalkylene group adduct of the compound represented by the general formula A or B at 80 to 100 ° C. it can.

The compound represented by the general formula C is phenol sulfonic acid or alkylphenol sulfonic acid or its alkali metal salt, alkaline earth metal salt or organic salt, and the compound represented by the general formula D is naphthalene sulfonic acid. Alternatively, it is an alkylnaphthalene sulfonic acid or its alkali metal salt, alkaline earth metal salt or organic salt.

As the alkyl group of the compounds represented by the general formulas C and D, a linear or branched alkyl group having 1 to 6 carbon atoms such as methyl, ethyl, propyl and isopropyl is used.

In the present invention, one kind or two or more kinds (a) selected from the compounds represented by the general formulas A and B and one kind selected from the compounds represented by the general formulas C and D or Two
The reaction molar ratio with the species or more (b) is (a) / (b) = 3 /
The range of 97 to 50/50 is particularly excellent as a cement dispersant, and more preferably (a) / (b) = 10/90 to 30/70.

One or more kinds (a) selected from the compounds represented by the general formulas A and B and one or more kinds (a) selected from the compounds represented by the general formulas C and D ( The method of formaldehyde co-condensation reaction with b) is not particularly limited, and it can be obtained by reacting under heat in the presence of (a) and (b) and formalin water. Examples of the alkali metal salt, alkaline earth metal salt and organic salt include inorganic salts such as sodium, potassium and magnesium, or organic salts such as ammonium, monoethanolamine, diethanolamine and triethanolaminemorpholine salts.

When the number of moles of alkylene oxide added to the compounds represented by the general formulas A and B is in the range of 4 to 100, slump retention is excellent. Below 4 the slump decline is large and 100
Above, not only the co-condensation becomes difficult, but also the dispersibility decreases.

In the present invention, in consideration of the degree of condensation due to the difference in monomers, for example, those having a slow condensation rate are pre-condensed to increase the degree of condensation of different kinds of monomers, so that the pre-condensed naphthalene sulfonic acid is used. Formaldehyde condensate or phenolsulfonic acid formaldehyde condensate can be used.

[0024] naphthalenesulfonic acid-formaldehyde condensates or phenol sulfonic acid formaldehyde condensate used in the present invention (c) is an oligomer (polymer) having an average molecular weight of 20,000 or less, represented in this oligomer general formula A, in B One or more compounds
By adding (a) and cocondensing with formaldehyde, a cocondensate having excellent dispersibility (fluidity) and prevention of slump loss can be obtained. However, when the average molecular weight is 20,000 or more, the obtained cocondensate has a broad molecular weight distribution, and the dispersibility and the slump loss preventive property tend to be deteriorated, which is not preferable.

The naphthalene sulfonic acid formaldehyde condensate used in the present invention also includes lower alkyl naphthalene sulfonic acid, that is, methyl naphthalene sulfonic acid formaldehyde condensate. The phenol sulfonic acid formaldehyde condensate also includes a cresol sulfonic acid formaldehyde condensate which is a lower alkylphenol sulfonic acid. These are manufactured by known methods.

For example, 1.10 to 1.50 mol of concentrated sulfuric acid is added at 120 ° C. to 1 mol of naphthalene and / or methylnaphthalene, the temperature is raised to 160 ° C. and the reaction is carried out for about 4 hours to obtain naphthalenesulfonic acid. Then, 2 to 10 mol of water for condensation is added and 0.7 to 1.0 mol of 35 to 40 wt% concentration formalin is added dropwise at about 95 ° C over about 4 hours, and then 3 to 50 at 100 to 105 ° C.
It can be obtained by reacting for a time.

Further, the formaldehyde condensate of phenolsulfonic acid and / or cresol may be either one obtained by condensing the sulfonated compound in the acidic region or one obtained by condensing it as an alkali salt and then condensing it, but is not limited thereto.

In the present invention, a naphthalenesulfonic acid formaldehyde condensate or a phenolsulfonic acid formaldehyde condensate (c) and one or more kinds (a) selected from the compounds represented by the general formulas A and B are used. The reaction molar ratio is (c) / (a) = 50/50 to 97 per monomer.
The range of / 3 is particularly excellent as a cement dispersant, and more preferably (c) / (a) = 70/30 to 90/10.

Formaldehyde co-condensation reaction of naphthalenesulfonic acid formaldehyde condensate or phenolsulfonic acid formaldehyde condensate (c) with one or more compounds selected from the compounds represented by the general formulas A and B (a). The method of (c) is not particularly limited.
It can be obtained by reacting with (a) and formalin water under heating in the presence of (a) and is not particularly limited.

The compound represented by the general formula E used in the present invention is a compound obtained by adding 4 to 100 mol of ethylene oxide or propylene oxide to phenol or alkylphenol, or a sulfonic acid thereof or an alkali metal salt of a sulfonic acid thereof. is there.

Examples of the metal salt include sodium, potassium and lithium. As the alkyl group, methyl,
1 carbon atom such as ethyl, propyl, isopropyl and nonyl
~ 9 straight or branched chain alkyl groups are used.

The number of moles of alkylene oxide added to the compound represented by the general formula E is in the range of 4 to 100 on average, and the slump retention is excellent in this range. When it is 4 or less, the slump is greatly lowered, and when it is 100 or more, not only the cocondensation is difficult but also the dispersibility is lowered.

The compound represented by the general formula F is melamine,
It is a melamine containing a methylol group or a melamine containing a sulfomethyl group. The compound represented by the general formula G is urea,
It is a methylol group-containing urea or a sulfomethyl group-containing urea. In the present invention, one kind or two or more kinds selected from the compounds represented by the general formulas F and G are used.

Of the compounds represented by the general formulas F and G,
The methylol group-containing melamine and urea are produced by a known method of adding formaldehyde.

Among the compounds represented by the general formulas F and G,
The compound having a sulfomethyl group can be obtained by introducing the sulfomethyl group into the corresponding raw material. The introduction of the sulfomethyl group may be carried out at the stage of the monomer, or may be carried out in the resulting cocondensate.

The method for introducing a sulfomethyl group into melamine can also be obtained by a known method, that is, by addition-condensing formaldehyde into melamine to introduce a methylol group, and then replacing the hydroxyl group with a sulfonating agent. There are 6 possible bonding sites, but at least 2 of them are considered to be used for forming the cocondensate according to the present invention. Therefore, it is possible to introduce sulfomethyl groups within 4 sites per melamine. The invention does not exclude either case.

The same applies to the case of introducing a sulfomethyl group of urea, and an introduced product having 1 to 2 sulfomethyl groups per urea is used.

As the sulfonating agent, known sulfonating agents such as sodium sulfite, sodium pyrosulfite and sodium hydrogen sulfite can be used.

The compound represented by the general formula H is phenol or alkylphenol, or its sulfonic acid or its alkali metal salt.

Examples of the metal salt include sodium, potassium and lithium. As the alkyl group, methyl,
1 carbon atom such as ethyl, propyl, isopropyl and nonyl
~ 9 straight or branched chain alkyl groups are used.

The formaldehyde used to produce these formaldehyde addition cocondensates preferably uses formalin at a concentration of 30-40% by weight in its aqueous solution. The amount of formaldehyde used is 1 with respect to the total number of moles of the compounds represented by the general formulas E to H which are monomers.
Approximately 3 times mol is suitable.

The formaldehyde addition cocondensation reaction is carried out in the range of pH 4 to 11 in the weak acid region to the basic region, for example, a conventional synthetic means such as phenylglycol (or sodium phenylglycolsulfonate), (containing a methylol group or a sulfomethyl group). Melamine and / or (containing methylol group or sulfomethyl group) urea, and formalin dropping reaction to phenol (or phenolsulfonic acid), or after adding phenylglycol (or sodium phenylglycolsulfonate) and phenol in advance (methylol group) Alternatively, there is a method in which melamine and / or (containing a methylol group or a sulfomethyl group) urea is added to carry out addition condensation, and the method is not particularly limited.

The constituent molar ratio of the compound (d) represented by the general formula E to the compound (e) represented by the general formula F and / or G is (d) :( e) = 0.1 to 1.0: 0.1 To 1.0, or the constituent molar ratio of the compound (d) represented by the general formula E, the compound (e) represented by the general formula F and / or G, and the compound (f) represented by the general formula H is (D) :( e) :( f) = 0.1
~ 1.0: 0.1 ~ 1.0: A range of 0.1 ~ 1.0 shows excellent effects.

One or more compounds selected from the compounds represented by the general formula E and the compounds represented by the following general formulas F to H (represented by the general formula F or G: The present invention shows a standard method for producing a formaldehyde addition co-condensate of the present invention, but the present invention is not limited thereto. Predetermined amount of phenyl glycol, (containing methylol group or sulfomethyl group) melamine and / or (containing methylol group or sulfomethyl group) urea, sodium phenolphenolsulfonate and water, and measure pH (7-8.5) and solid content concentration. After the adjustment, it is charged in a reaction vessel and 37% formalin water is added dropwise at 80 to 90 ° C. over 1 to 3 hours. After the dropping, it can be obtained by stirring under reflux for 3 to 30 hours and cooling.

The average molecular weight of the cocondensate of the present invention is from 10,000 to
30,000 good Masui. (The average molecular weight is calculated by gel permeation chromatography / molecular weight conversion based on sodium polystyrene sulfonate ).

The amount of the cement dispersant of the present invention added to concrete is preferably 0.05 to 3.0% by weight, more preferably 0.5 to 1.0% by weight, based on the cement.

The cement dispersant of the present invention can be used in combination with other dispersants. The dispersant may be one that is generally used as a dispersant for concrete, but is preferably a naphthalene sulfonate formaldehyde condensate, a melamine sulfonate formaldehyde condensate, a polycarboxylic acid or its ester or its salt. , Mainly purified lignin sulfonic acid or its salt, polystyrene sulfonate, cement dispersant having phenol skeleton (for example, formaldehyde co-condensate with other monomer capable of co-condensing phenol sulfonic acid), aniline sulfonic acid Cement dispersants as components (for example, formaldehyde co-condensation products with other monomers capable of co-condensing aniline sulfonic acid) and the like, which are conventionally referred to as high-performance water reducing agents, can be mentioned. An appropriate combination ratio is 5 to 95% by weight based on the cement dispersant of the present invention.

The cement dispersant of the present invention is suitable for civil engineering, construction,
It is used for a hydraulic composition of cement such as a secondary product and is not particularly limited.

The cement dispersant of the present invention can be used in combination with known additives (materials). For example, AE agent, AE
Water-reducing agent, superplasticizer, high-performance water-reducing agent, retarder, early-strengthening agent, accelerator, foaming agent, foaming agent, water retention agent, thickener, waterproofing agent, defoaming agent, water-soluble polymer, surfactant Various agents, cement paste mortar, various cements that make up concrete,
The thing added to hydraulic compositions, such as a blast furnace slag, a fly ash, and a silica fume, is mentioned.

[0050]

EXAMPLES The present invention will be specifically described below, but the present invention is not limited to these examples. In addition,% in the following examples is% by weight.

The average molecular weight of the condensate or co-condensate shown in the examples is obtained from the molecular weight by gel permeation chromatography / conversion of sodium polystyrene sulfonate.

Example 1 Production Example An ethylene oxide adduct of phenol (alkylphenol) and / or naphthol (alkylnaphthol) and phenolsulfonic acid (alkylphenolsulfonic acid) and / or naphthalenesulfonic acid (alkylnaphthalenesulfonic acid) were placed in a reaction vessel equipped with a stirrer. ) Or its total alkali metal salt or organic salt of 1 mol, 3 mol of water are charged at the same time and heated to 85 ° C. Next, 0.95 mol of 35% formalin was added dropwise over 1 hour and then condensed at 96 ° C. for 5 to 50 hours. After cooling, neutralize with 40% sodium hydroxide in the case of acidic condensate. Add water to these condensates to add 30
% To obtain a dispersant.

Table 1 shows the content of the dispersant produced and the weight average molecular weight according to the production example. Symbol and content of each raw material Those belonging to the compound represented by the general formula A were designated as symbol A. -Symbol A-1; 8 mol of ethylene oxide with phenol oxide-Symbol A-2; 30 mol of ethylene oxide with metacresol-Symbol A- 3 ; 115 mol of ethylene oxide with metacresol-added compound represented by the general formula B The symbol B belongs to them. -Symbol B-1; naphthol ethylene oxide 10 mol adduct-Symbol B-2: butyl naphthol ethylene oxide 35 mol adduct A compound belonging to the compound represented by the general formula C was designated as symbol C. -Symbol C-1; phenol sulfonic acid-Symbol C-2; sodium metacresol sulfonate The compound belonging to the compound represented by the general formula D was designated as symbol D. -Symbol D-1; naphthalene sulfonic acid-Symbol D-2; ammonium methylnaphthalene sulfonate

[0054]

[Table 1]

The concrete was evaluated as follows for the dispersants in Table 1. Concrete mix W / C = 25%, s / a = 43%, C = 420kg / m ³ Each symbol and content of materials used W: Tap water C: Central ordinary Portland cement Specific gravity = 3.16 S: Kinokawa sand sand Specific gravity = 2.56 G: Crushed stone from Takarazuka Specific gravity = 2.60 s / a: Sand / sand + gravel (volume ratio) Physical property test of concrete Fluidity: Slump flow (cm), according to JIS-A 1101 method. Evaluation Method A dispersant was added so that the slump flow was 60 ± 5 cm, and the slump flow immediately after kneading and until 60 minutes elapsed and the setting time (hour-minute) were measured. The evaluation results of the dispersant are shown in Table 2.

[0056]

[Table 2]

* 1 Weight% as solid content relative to cement * 2 Symbol NS; Naphthalene type trade name; Mighty 150
(Manufactured by Kao Corporation) * 3 Symbol MS; Melamine series product name; Mighty 150V-2
(Manufactured by Kao Corporation).

Example 2 Preparation Example of Naphthalenesulfonic Acid Formaldehyde Condensate 1.0 mol of naphthalene was charged into a stirring reaction vessel, the temperature was raised to 120 ° C., and 1.28 mol of 98% sulfuric acid was added with stirring. Next, the temperature is raised to 160 ° C. and the mixture is stirred for 4 hours to obtain naphthalenesulfonic acid. Thereafter, the mixture was cooled to 90 ° C., 3 mol of warm water was added, and 0.95 mol of 37% formalin was added over 4 hours with stirring. Then, raise the temperature to 102 ° C and react for 1 to 30 hours,
A naphthalenesulfonic acid formaldehyde condensate having a changed molecular weight is obtained. The weight average molecular weights and symbols of the condensates obtained in Production Examples are shown below. -Symbol NS-1; molecular weight = 350 -Symbol NS-2; molecular weight = 3300 -Symbol NS-3; molecular weight = 6500 -Symbol NS-4; molecular weight = 10500 .

Phenolsulfonic acid formaldehyde condensation
Preparation example of compound Compound 1.0 mol of phenol is charged into a stirred reaction vessel, heated to 100 ° C, and 1.05 mol of 98% sulfuric acid is added with stirring. Stir for 4 hours to obtain phenol sulfonic acid. Then cool to 90 ° C, add 3 mol of warm water, and stir at 37% formalin.
Add 0.5-0.8 mole over 4 hours. Then 100 ℃
The temperature is raised to 1 hour and the reaction is carried out for 1 to 15 hours to obtain a phenolsulfonic acid formaldehyde condensate having a changed molecular weight.
The weight average molecular weights and symbols of the condensates obtained in Production Examples are shown below. -Symbol FS- 1 ; molecular weight = 5500.

The contents and symbols of the compounds represented by the general formulas A and B used for the cocondensation are shown below. -Symbol FG- 1 ; Average number of moles of phenylglycol ethylene oxide added = 5.1-Symbol FG- 2 ; Average number of moles of phenylglycol ethylene oxide added = 20.5-Symbol FG- 3 ; Average number of moles of phenylglycol ethylene oxide = 92.3-Symbol FG- 4 ; sodium phenylglycolsulfonate ethylene oxide addition average number of moles = 5.1-Symbol NG-1; naphthol ethylene oxide adduct ethylene oxide addition average number of moles = 4.8.

Preparation Example of Cocondensate (1) FG-1 was added to NS- 2 condensate in a stirred reaction vessel at a reaction molar ratio.
Added to reach 55/45, at 95 ° C., it was added dropwise a molar amount corresponding to 37% formalin NS- 2 over 1 hour,
After heating to 105 ℃ and reacting for 3 to 50 hours, cool to 50%
Adjust to pH 8 with sodium hydroxide and add water to remove solids.
It was adjusted to 20% to obtain a cocondensate. In the following, a combination of the condensate and the compounds represented by the general formulas A and B, a formalin molar ratio, and a condensation time were changed in the same manner to obtain co-condensates of Y-1 to Y- 4 having different molecular weights. . Table 3 shows the contents of co-condensation.

Preparation Example of Cocondensate (2) The FS- 1 condensate in a stirred reaction vessel was adjusted to pH 8 with 50% sodium hydroxide, and 2 mol of water and FG- 4 were mixed at a reaction molar ratio of 90 /.
Add 10% and add 37% formalin to FS at 90 ° C.
-1 was added dropwise over 1 hour, then 100
After reacting at 0 ° C. for 3 to 50 hours, water was added to adjust the solid content to 20% to obtain a Y-5 cocondensate . Table 3 shows the contents of co-condensation.

[0063]

[Table 3]

Table 4 shows the mixing conditions of the evaluation concrete as a cement dispersant .

[0065]

[Table 4]

The concrete was produced by mixing the concrete materials shown in Table 4 and the cement dispersant with a tilting mixer at 25 rpm.
It was adjusted by kneading for 3 minutes. After measuring the slump value, it was further rotated at 4 rpm for 60 minutes, and the slump value after 60 minutes was measured. The amount of the dispersant added was such that the initial slump value was 20 ± 1 cm. The slump value was measured by the JIS-A1101 method. The measurement results are shown in Table 5.

[0067]

[Table 5]

* 1 Weight% as solid content relative to cement * 2 Symbol FS; Phenol sulfonate formaldehyde condensate (corresponding to ethylene oxide addition mole number = 0) According to Synthesis Example No. 7 of Patent No. 1097647 * 3 Symbol NS; naphthalene type (Mighty 150 Kao Corporation)
* 4 MS: Melamine type (Mighty 150V-2 (Kao Corporation).

Evaluation results As shown in Table 5, the dispersant of the present invention can obtain fluidity with a smaller addition amount as compared with the comparative product, and the difference between the slump value immediately after and after 60 minutes is small. That is, it shows an excellent water reducing effect and a remarkable effect in preventing slump loss.

Example 3 Production Example of Cocondensate (1) Phenyl glycol and sulfomethyl group-containing melamine (1 mol of melamine skeleton is a sulfomethylation reaction product) and / or sodium phenolsulfonate are placed in a reaction vessel equipped with a stirrer. A fixed amount of 1N sodium hydroxide solution and water are added to adjust the pH of this solution to 8.0 and the solid content concentration to 45% by weight. Then, the adjusted solution is heated to 85 ° C., 37% formalin is added with stirring, and the reaction mixture is stirred under reflux for 3 to 30 hours. Then, cool to 30 ℃,
Water is added to adjust the concentration to 25% by weight to obtain the dispersant of the present invention. Table 6 below shows the content of the cocondensate of the present invention produced according to Production Example (1). The contents of the phenyl glycol used (number of moles of ethylene oxide added) are shown below. Further, the number of moles of formalin in the table is the number of moles as formaldehyde (the same applies to the production examples below).

Symbol and content of phenyl glycol used in Production Example (1) -Symbol PG- 1 ; average number of moles of phenylglycol ethylene oxide added = 5.1-Symbol PG- 2 ; average number of moles of phenylglycol ethylene oxide added = 92.3 Symbol PG- 3 ; sodium phenylglycolsulfonate ethylene oxide addition average number of moles = 5.1. Symbol PG- 4 ; methylphenylglycol ethylene oxide addition average number of moles = 5.1. Symbol PG- 5 ; nonylphenylglycol ethylene oxide addition average number of moles. = 5.1

[0072]

[Table 6]

Production Example of Cocondensate (2) Phenyl glycol (PG- 1 ) in a reaction vessel equipped with a stirrer,
Melamine and sulfomethyl group-containing urea (1 mol of the urea skeleton is a sulfomethylation reaction product) and / or sodium phenolsulfonate are charged in a predetermined amount, and 1N sodium hydroxide aqueous solution and water are added to bring the solution to pH 8.0. To
Adjust the solids concentration to 45% by weight. Then, the adjusted solution is heated to 85 ° C., 37% formalin is added with stirring, and the reaction mixture is stirred under reflux for 3 to 30 hours. Then, the mixture is cooled to 30 ° C. and water is added to adjust it to 25% by weight to obtain the dispersant of the present invention. Table 7 below shows the content of the cocondensate of the present invention produced according to Production Example (2).
The content of the phenyl glycol used (number of moles of ethylene oxide added) is the same as in Production Example (1).

[0074]

[Table 7]

[0075] Co-condensate of preparation (3) phenyl glycolic sodium sulfonate in a stirred reaction vessel (PG- 3) and sulfomethyl group-containing melamine (methylol added 3 moles, of one mole sulfomethylated reactant)及beauty a predetermined amount was charged methylation phenol, by adding 1 N aqueous sodium hydroxide and water solution pH8.0
Then, the solid content concentration is adjusted to 45% by weight. Then, the adjusted solution is heated to 85 ° C., 37% formalin is added with stirring, and the reaction mixture is stirred under reflux for 3 to 30 hours. Then, the mixture is cooled to 30 ° C. and water is added to adjust it to 25% by weight to obtain the dispersant of the present invention. Table 8 below shows the content of the cocondensate of the present invention produced according to Production Example (3).
The content of the phenyl glycol used (number of moles of ethylene oxide added) is the same as in Production Example (1).

[0076]

[Table 8]

Production Example of Cocondensate (4) A reaction vessel equipped with a stirrer was charged with sodium phenylglycolsulfonate (PG- 3 ), melamine or trimethylolmelamine and sodium phenolsulfonate in a predetermined amount, and 1N sodium hydroxide was added. An aqueous solution and water are added to adjust the pH of the solution to 8.0 and the solid content concentration to 45% by weight. Next, raise the temperature of this adjusted solution to 85 ° C and stir it at 37%.
Formalin is added and the reaction mixture is stirred under reflux for 3-30 hours. Then, the mixture is cooled to 30 ° C. and water is added to adjust it to 25% by weight to obtain the dispersant of the present invention. Table 9 below shows the content of the cocondensate of the present invention produced according to Production Example (4). The content of the phenyl glycol used (number of moles of ethylene oxide added) is the same as in Production Example (1).

[0078]

[Table 9]

Table 10 shows the compounding conditions of evaluation concrete as a cement dispersant .

[0080]

[Table 10]

The concrete was evaluated by kneading the material and the dispersant for cement in a tilting mixer at 25 rpm × 3 minutes according to the concrete composition shown in Table 5. After measuring the slump value, it was further rotated at 4 rpm for 60 minutes, and the slump value after 60 minutes was measured. The slump value was measured by the JIS-A 1101 method. Further, the initial slump value was adjusted to 20 ± 1 cm by adjusting the addition amount of the dispersant of the present invention and the comparative example. Table 11 shows the measurement results.

[0082]

[Table 11]

* 1 Weight% as a solid content relative to cement * 2 Symbol FS; Phenol sulfonate formaldehyde condensate (corresponding to ethylene oxide addition mole number = 0) According to Synthesis Example No. 7 of Patent No. 1097647 * 3 Symbol NS; naphthalene type (Mighty 150 Kao Corporation)
* 4 MS: Melamine type (Mighty 150V-2 (Kao Corporation).

Evaluation Results As is clear from Table 11, the dispersant of the present invention exhibits fluidity with a smaller addition amount as compared with the comparative product, and the difference between the slump value immediately after and after 60 minutes is small. That is, it shows an excellent water reducing effect and a remarkable effect in preventing slump loss.

[0085]

When the cement dispersant according to the present invention is added to the cement composition, there is no slump loss for a long period of time, and therefore, transportation troubles due to pumping can be eliminated. Furthermore, since the cement dispersant according to the present invention improves the fluidity of the cement composition, it facilitates the work of filling the mold, and the cement dispersant according to the present invention also has a large water reducing effect, so that it can be applied to high-strength concrete. Applications are also expected.

Claims (10)

[Claims] 1. An oxyalkylene group having 2 to 3 carbon atoms 4 to
A formaldehyde co-condensate of one or more selected from aromatic compounds introduced with 100 mol and one or more selected from substances capable of formaldehyde co-condensation, having an average molecular weight of 10,000 to 30,000,
And a cement dispersant having a sulfonic acid group or sulfomethyl group cocondensates in. 2. An oxyalkylene group having 2 to 3 carbon atoms 4 to
The cement dispersant according to claim 1, wherein the aromatic compound introduced with 100 mol is a benzene ring derivative or a naphthalene ring derivative. 3. A substance capable of co-condensing formaldehyde is phenol or a derivative thereof, naphthalene or a derivative thereof,
The cement dispersant according to claim 1 or 2, which is melamine or a derivative thereof and urea or a derivative thereof. 4. One or more selected from compounds represented by the following general formulas A and B (a) and one selected from compounds represented by the following general formulas C and D: The cement dispersant according to claim 3, which comprises, as a main component, a formaldehyde co-condensate with one or more kinds (b). Embedded image (In the formula, R ₁ and R ₂ ; H or an alkyl group RO ₁ and RO ₂ having 1 to 9 carbon atoms; an oxyalkylene group n ₁ and n ₂ having 2 to 3 carbon atoms; and an integer Z ₁ and Z of 4 to 100. ₂ ; H or SO ₃ X ₁ X ₁ ,; H, represents a monovalent or divalent metal, an ammonium group, an amino group or a substituted amino group.) (In the formula, R ₃ and R ₄ ; H or an alkyl group having 1 to 6 carbon atoms X ₂ and X ₃ ; H, an alkali metal salt, an alkaline earth metal salt, or an organic salt is shown.) 5. One or more selected from the compounds represented by the general formulas A and B (a) and one or two selected from the compounds represented by the general formulas C and D. The cement dispersant according to claim 4, wherein the reaction molar ratio with the above (b) is (a) / (b) = 3/97 to 50/50. 6. oligos with 20, 000 or less average molecular weight
A naphthalene sulfonic acid formaldehyde condensate or a phenol sulfonic acid formaldehyde condensate (c) which is a mer or polymer, and a general formula A according to claim 4.
The cement dispersant according to claim 3, which comprises a formaldehyde cocondensate with one or more compounds (B) represented by B as a main component. 7. oligos with 20, 000 or less average molecular weight
The reaction molar ratio of the naphthalene sulfonic acid formaldehyde condensate or phenol sulfonic acid formaldehyde condensate (c), which is a polymer or a polymer, with one or more compounds represented by the general formulas A and B (a) is The cement dispersant according to claim 6, wherein (c) / (a) = 50/50 to 97/3 per monomer. 8. One or more compounds selected from compounds represented by the following general formula E and compounds represented by the following general formulas F to H (provided that in the general formula F or G, 4. The cement dispersant according to claim 3, which comprises a cocondensate obtained by addition-condensing the compound represented by the formula) with formaldehyde. [Chemical 3] (Wherein, RO _3; oxyalkylene group n ₃ carbon atoms 2-3; integer of _{4 ~100 R 5, R 6;} H or an alkyl group X ₄ 1 to 9 carbon atoms, X _5; H, sulfone group Or an alkali metal salt Y _{1 to} Y ₅ ; H, CH ₂ OH or CH ₂ SO ₃ Z (Z is an alkali metal salt)
Provided that when X ₄ is H, at least one of Y _{1 to} Y ₅ is CH ₂ SO ₃ Z and / or X ₅ is SO ₃ X. ) 9. The constituent molar ratio of the compound (d) represented by the general formula E and the compound (e) represented by the general formula F and / or G is (d) :( e) = 0.1 to 1.0. The cement dispersant according to claim 8, which is 0.1 to 1.0. 10. A compound (d) represented by the general formula E:
The constituent molar ratio of the compound (e) represented by the general formula F and / or G to the compound (f) represented by the general formula H is (d):
(E): (f) = 0.1 to 1.0: 0.1 to 1.0: 0.1 to 1.0
The cement dispersant according to claim 8 or 9, which is