JPH06157098A - Cement admixture - Google Patents

Abstract

PURPOSE:To provide a cement admixture excellent in dispersibility and slump retentivity, and low in cement curing delay, consisting mainly of a copolymer from a specific epoxy compound and formaldehyde condensate of specific compound. CONSTITUTION:The cement admixture consist mainly of a copolymer from (A) an epoxy compound of formula I (X1 is O-A1-O or (O-A2)n1-O; A1 is 1-10C alkylene group or aromatic ring; A2 is 2-4C alkylene; R1 1-12C alkyl etc.; n1 is 2-100) and/or another epoxy compound of formula II (X2 is O-A3-O or (O-A4)n2-O; A3 is the same as A1; A4 is the same as A2; n2 is the same as n1) and (B) formaldehyde condensate(s) of compound(s) of formula III and/or formula IV (R2 and R3 are each H or 1-6C alkyl; X3 and X4 are each H, alkali metal, etc.).

Description

Detailed Description of the Invention

[0001]

This invention relates to cement admixtures. More specifically, it relates to a cement admixture 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
The cement dispersant used for the purpose of improving the fluidity of the hydraulic composition, a naphthalenesulfonic acid formaldehyde condensate salt (hereinafter referred to as naphthalene system), a melamine sulfonic acid formaldehyde condensate salt (hereinafter referred to as melamine system), 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 a big problem that the

[0004]

Means for Solving the Problems As a result of earnest research, the inventors of the present invention clarified the characteristics of dispersibility and slump loss of various surfactants in concrete, and from that knowledge, design the structure of an admixture. As a result, we have completed a cement admixture that has excellent dispersibility and slump retention characteristics that cannot be obtained with existing admixtures, and that has a small hardening delay.

That is, the present invention is represented by the epoxy compound represented by the following general formula (A) and / or the epoxy compound represented by the following general formula (B) and the following general formula (C). Formaldehyde condensate of compound and / or the following general formula
The present invention relates to a cement admixture containing a copolymer of a compound represented by (D) and a formaldehyde condensate as a main component.

[0006]

[Chemical 4]

(However, X ₁ ; -OA ₁ -O- or-(OA ₂ ) _{n 1} -O-A ₁ ; alkylene group having 1 to 10 carbon atoms or aromatic ring A ₂ ; same or different carbon number 2 4 alkylene group, R ₁ ; C 1-12 alkyl group or phenyl group which may be accompanied by a substituent, n ₁ ; 2-100 integer.

[0008]

[Chemical 5]

(Provided that X ₂ ; -OA ₃ -O- or-(OA ₄ ) n ₂ -O-A ₃ ; alkylene group having 1 to 10 carbon atoms or aromatic ring A ₄ ; same or different carbon number 2 4 represents an alkylene group, n ₂ ; an integer of _{2 to} 100.

[0010]

[Chemical 6]

(Provided that R ₂ , R ₃ ; H or an alkyl group having 1 to 6 carbon atoms, X ₃ , X ₄ ; H or an alkali metal or amino group, a substituted amino group) are used in the present invention. Examples of the compound represented by the general formula (A) include monoepoxy compounds such as alkyl ethylene glycol monoglycidyl ether, alkyl polyethylene glycol monoglycidyl ether, alkyl polypropylene glycol monoglycidyl ether, and phenyl polyethylene glycol monoglycidyl ether. .

Examples of the compound represented by the general formula (B) include diepoxy compounds such as ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether and polypropylene glycol diglycidyl ether. .

As the alkyl group of the epoxy compound represented by the general formula (A), a linear or branched alkyl group having 1 to 12 carbon atoms is used.

The addition mole number of the oxyalkylene group of the epoxy compound represented by the general formula (A) and the epoxy compound represented by the general formula (B) is in the range of 1 to 100, which is excellent in dispersibility and slump retention. If it exceeds, the dispersibility is poor.

The compound represented by the general formula (C) is sulfonic acid of phenol or alkylphenol or its water-soluble salt, and the compound represented by the general formula (D) is sulfonic acid of naphthol or alkylnaphthol or its water-soluble salt. And these formaldehyde condensates are used.

Compound represented by general formula (C) and general formula
The alkyl group of the compound represented by (D) is methyl,
A straight chain or branched chain alkyl group having 1 to 6 carbon atoms such as ethyl, propyl and isopropyl is used.

The formaldehyde condensate of the compound represented by the general formula (C) and the formaldehyde condensate of the compound represented by the general formula (D) are produced by known methods. That is, a sulfonic acid of (alkyl) phenol represented by the general formula (C) or a water-soluble salt thereof and a sulfonic acid of (alkyl) naphthol represented by the general formula (D) or a water-soluble salt thereof are added in the presence of formaldehyde. It can be obtained by heating and reacting, but is not limited to this production method. Examples of these sulfonates include alkali metal salts such as sodium, potassium and magnesium, or salts such as ammonium, monoethanolamine, diethanolamine, triethanolamine and morpholine.

The epoxy compound represented by the general formula (A) and / or the epoxy compound represented by the general formula (B) and the general formula
Formaldehyde condensate of compound represented by (C) and /
Alternatively, the polymerization of the compound represented by the general formula (D) with the formaldehyde condensate can be obtained by heating and stirring in the presence of a catalyst. Examples of the catalyst used in that case include triethylbenzylammonium chloride and tetramethylammonium chloride.

Polymerization is carried out in the presence of this catalyst in the temperature range of usually 50 to 100 ° C. for 2 to 20 hours to obtain the admixture of the present invention.

The polymerization method is carried out by using a formaldehyde condensate of an epoxy compound represented by the general formula (A) and / or an epoxy compound represented by the general formula (B) and a compound represented by the general formula (C) and / or Method by batch charging of formaldehyde condensate of compound represented by general formula (D), or general formula
Represented by the epoxy compound represented by the general formula (A) and / or the general formula (B) during the formaldehyde condensation of the compound represented by the (C) and / or the compound represented by the general formula (D) Any method of adding an epoxy compound and polymerizing may be used, and the method is not limited.

The epoxy compound represented by the general formula (A) and / or the epoxy compound represented by the general formula (B) ((A), (B))
And a formaldehyde condensate of the compound represented by the general formula (C) and / or a formaldehyde condensate of the compound represented by the general formula (D) (abbreviated as (C), (D)) is , (A), (B) / (C), (D) = 10 to 90/90 to 10 mol% ((C),
(D is per monomer before condensation) is suitable,
~ 50 / 50-98 mol% is more excellent in dispersibility and slump retention.

The weight average molecular weight of the formaldehyde condensate of the compound represented by the general formula (C) and the formaldehyde condensate of the compound represented by the general formula (D) is in the range of 1000 to 30,000, especially when copolymerizing. It is suitable, and if it exceeds 30,000, the dispersibility tends to decrease due to an increase in the polymer region.

The weight average molecular weight of the copolymer (gel permeation chromatography method, converted to sodium polystyrenesulfonate) may be in a wide range, but it is preferably in the range of 5,000 to 100,000, and in the range of 10,000 to 50,000. Properties and slump retention are particularly preferred.

The admixture of the present invention to be added to concrete can be used in an amount of 0.05 to 5.0% by weight in terms of active ingredient based on cement, but 0.1 to 2.
Used in the range of 0% by weight.

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

The admixture of the present invention can be used in combination with known additives (materials). One example is 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, antifoaming agent, water-soluble polymer , Defoaming agents, various kinds of surfactants, cement paste mortar, various cements constituting concrete, blast furnace slag, fly ash, silica fume, and other hydraulic compositions.

[0027]

EXAMPLES The present invention will be specifically described below, but the present invention is not limited to these examples. The percentages in the following examples are weight percentages.

(1) The symbol A indicates the method for producing the admixture of the present invention used in the examples and the produced product of the present invention. Production Example 1 (Symbol A-1 in Example) In a reaction vessel equipped with a stirrer, 0.2 mol of lauryl polyethylene glycol (number of moles of ethylene oxide added = 15) monoglycidyl ether, formaldehyde condensate of sodium phenolsulfonate (weight average molecular weight = 7200). 0.8 mol (as sodium phenolsulfonate) and 4 g of triethylbenzylammonium chloride were charged, water was added to adjust the solid content to 45%, the temperature was raised to 80 ° C., and polymerization was performed for 6 hours to obtain a copolymer having a molecular weight of 35,000. .

Production Example 2 (Symbol A-2 in Example) In a reaction vessel equipped with a stirrer, 0.5 mol of phenyl polyethylene glycol (number of moles of ethylene oxide added = 5) monoglycidyl ether and formaldehyde condensation product of sodium methylphenolsulfonate (weight) (Average molecular weight = 24000)
0.5 mol (as sodium methylphenol sulfonate), 3 g of triethylbenzylammonium chloride
Was added, water was added to adjust the solid content to 45%, the temperature was raised to 70 ° C. and polymerization was carried out for 7 hours to obtain a copolymer having a molecular weight of 42000.

Production Example 3 (Symbol A-3 in the Example ) Diglycidyl ether was added to a reaction vessel equipped with a stirrer, polyethylene glycol (number of moles of ethylene oxide added = 5).
0.4 mol, formaldehyde condensate of sodium naphthol sulfonate (weight average molecular weight = 1600) 0.6 mol (as sodium naphthol sulfonate), 3 g of tetramethylammonium chloride were charged, and water was added to make the solid content 45%, and the temperature was raised to 80 ° C. Polymerize for 3 hours by heating
12000 copolymers were obtained.

Production Example 4 (Symbol A-4 in Example) Polyglyceride (ethylene oxide addition mole number = 20) diglycidyl ether was placed in a reaction vessel equipped with a stirrer.
Formaldehyde condensate of 0.2 mol, sodium isopropyl naphthol sulfonate (weight average molecular weight = 1600)
0.8 mol (as sodium isopropyl naphthol sulfonate), 2 g of tetramethyl ammonium chloride
Then, water was added to adjust the solid content to 45%, the temperature was raised to 70 ° C. and polymerization was carried out for 4 hours to obtain a copolymer having a molecular weight of 15,000.

Production Example 5 (Symbol A-5 in Example) Polyglycol (ethylene oxide addition mole number = 45) diglycidyl ether was placed in a reaction vessel equipped with a stirrer.
0.1 mol, formaldehyde condensate of sodium phenolsulfonate (weight average molecular weight = 5700) 0.9 mol (as sodium phenolsulfonate), 1 g of tetramethylammonium chloride were charged, and water was added to make the solid content 45%, and the temperature was raised to 80 ° C. Polymerize by heating for 6 hours, molecular weight
22000 copolymers were obtained.

Production Example 6 (Symbol A-6 in the Example ) Diglycidyl ether was added to a reaction vessel equipped with a stirrer and polyethylene glycol (ethylene oxide addition mole number = 55).
0.1 mol, phenyl polyethylene glycol (ethylene oxide addition mol number = 3) monoglycidyl ether
0.1 mol, sodium phenolsulfonate formaldehyde condensate (weight average molecular weight = 5700) 0.5 mol (as sodium phenolsulfonate), sodium naphtholsulfonate formaldehyde condensate (weight average molecular weight = 1600) 0.3 mol (sodium naphtholsulfonate As a), 3 g of tetramethylammonium chloride was charged, the temperature was raised to 70 ° C., and polymerization was performed for 3 hours. After completion of the polymerization, the pH was adjusted to 7.5 with a 30% aqueous sodium hydroxide solution to obtain a copolymer having a molecular weight of 47,000.

The comparative admixtures used in the examples are shown below. Reference symbol NS in the examples; naphthalene-based admixture (Mighty 15
0 (manufactured by Kao Corporation) Symbol MS in the Examples: Melamine admixture (Mighty 150
V-2 (manufactured by Kao Corporation) (2) Evaluation as cement admixture Table 1 shows the mixing conditions of concrete.

[0035]

[Table 1]

The concrete is produced by mixing the concrete material and cement admixture shown in Table 1 with a tilting mixer at 25 rpm.
It was prepared 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 admixture was added so that the initial slump value was 20 ± 1 cm. The slump value was measured by the JIS-A 1101 method. The measurement results are shown in Table 2.

[0037]

[Table 2]

(Evaluation Results) As shown in Table 2, the admixture of the present invention can provide fluidity with a smaller addition amount than the comparative product, and has a small difference between the slump value immediately after and 60 minutes later. That is, it shows an excellent water reducing effect and a remarkable effect in preventing slump loss.

[0039]

When the cement admixture according to the present invention is added to the cement composition, there is no slump loss for a long period of time, so that transport troubles due to pumping are eliminated.
Furthermore, since the cement admixture according to the present invention improves the fluidity of the cement composition, it facilitates the work of filling the formwork, and the cement admixture according to the present invention also has a large water-reducing effect. Applications are also expected.

Claims (2)

[Claims] 1. An epoxy compound represented by the following general formula (A) and / or an epoxy compound represented by the following general formula (B), and formaldehyde of a compound represented by the following general formula (C): A cement admixture containing a condensate and / or a copolymer of a compound represented by the following general formula (D) and a formaldehyde condensate as a main component. [Chemical 1] (However, X ₁ ; -OA ₁ -O- or-(OA ₂ ) _{n 1} -O-A ₁ ; alkylene group having 1 to 10 carbon atoms or aromatic ring A ₂ ; same or different alkylene having 2 to 4 carbon atoms A group, R ₁ ; a phenyl group which may be accompanied by an alkyl group having 1 to 12 carbon atoms or a substituent, n ₁ ; an integer of 2 to 100). (However, X ₂ ; -OA ₃ -O- or-(OA ₄ ) n ₂ -O-A ₃ ; alkylene group having 1 to 10 carbon atoms or aromatic ring A ₄ ; same or different alkylene having 2 to 4 carbon atoms A group, n ₂ ; an integer of _{2 to} 100). (However, R ₂ and R _{3 are} H or an alkyl group having 1 to 6 carbon atoms, X ₃ and X _{4 are} H, an alkali metal or an amino group, and a substituted amino group.) 2. A weight average molecular weight of the formaldehyde condensate of the compound represented by the general formula (C) and the formaldehyde condensate of the compound represented by the general formula (D) is 1000 to 30,000. Item 1. The cement admixture according to item 1.