JP2001270749A - Cement admixture and method for producing cement hardened body using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a cement hardened body having high waterproofness using a cement admixture. SOLUTION: The subject cement admixture comprises a polyhydric alcohol- substituted succinic ester and/or a salt thereof obtained by esterification between (A) a polyhydric alcohol with 2-8 hydroxyl groups and (B) a substituted succinic acid pref. having a 6-36C alkyl or alkenyl group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cement admixture, and provides a method for producing a hardened cement having excellent waterproofness.

[0002]

2. Description of the Related Art Conventionally, hardened cements widely used in the fields of civil engineering and construction include waterproof cement (paste, mortar), cement putty, cement-based ground preparation mortar, porcelain tile mortar, self-leveling mortar. , Cement molded products (wood cement board, fiber reinforced cement board, lightweight inorganic board, asbestos slate board, asbestos barride board, etc.), lightweight concrete, concrete, etc., especially underground and exterior walls, water tanks, pools,
Structures exposed to rainwater and water, such as wastewater treatment facilities, verandas, building exterior walls, kitchens, and bathrooms, are required to have excellent waterproofness.

Examples of admixtures for imparting waterproofness (water absorption resistance) to hardened cement bodies include higher fatty acid (oleic acid, stearic acid, etc.) soaps, paraffin, asbestos, synthetic high molecular compounds, calcium chloride, sodium silicate and the like. Many waterproofing agents such as inorganic silica are known. For example, Japanese Patent Publication No. 46-39120 proposes a liquid concrete or concrete block admixture using silicates, urea and a surfactant. Japanese Patent Publication No. 48-23174 discloses alkenyl succinic acid or a water-soluble salt or anhydride thereof. 5th page 31-3 of the same specification
Line 3 describes an additive consisting of calcium stearate. JP-B-61-24356 discloses an admixture containing a water-soluble salt of an alkenyl or alkyl succinate. JP-A-6-171997 discloses an additive for cement comprising a compound obtained by esterification of a polyhydric alcohol and a higher fatty acid.

[0004] However, the cement admixture is still insufficient in terms of performance and economy in that the waterproofness is insufficient, the physical properties are unfavorably affected, or it is necessary to add a relatively large amount of the cement admixture. Have not been satisfied.

[0005]

In view of such circumstances, the present inventors have provided a cement admixture that imparts excellent waterproofness to a hardened cement body and a method for producing a hardened cement body using the same. As a technical issue, as a result of intensive research,
The present invention has been completed.

[0006]

That is, the present invention relates to a cement admixture having the following constitution and a method for producing a hardened cement body using the same.

[0007] The invention of claim 1 provides a polyhydric alcohol-substituted succinic ester and / or polyhydric alcohol obtained by esterifying a polyhydric alcohol (A) having 2 to 8 hydroxyl groups with a substituted succinic acid (B). The polyhydric alcohol-substituted succinic acid ester salt comprises a cement admixture.

According to a second aspect of the present invention, in the first aspect, the polyhydric alcohol (A) having 2 to 8 hydroxyl groups is represented by the general formula (1): (Wherein, n represents an integer of 0 to 6), which is a polyhydric alcohol represented by the formula of a cement admixture.

According to a third aspect of the present invention, in the first aspect, the polyhydric alcohol (A) is represented by the following formula (2): And a cement admixture which is a polyhydric alcohol represented by

A fourth aspect of the present invention is the cement admixture according to any one of the first to third aspects, wherein the substituted succinic acid (B) is a substituted succinic acid having an alkyl group or an alkenyl group having 6 to 36 carbon atoms. .

[0011] The invention of claim 5 is the invention according to claims 1 to 4, wherein 1 mole of the substituted succinic acid (B) to 1 mole of the hydroxyl equivalent is equivalent to 1 mole of the polyhydric alcohol (A) having 2 to 8 hydroxyl groups. And / or a cement admixture comprising a polyhydric alcohol-substituted succinate and / or salts of the polyhydric alcohol-substituted succinate.

A sixth aspect of the present invention is a method for producing a hardened cement containing 0.1 to 5% by weight of the cement admixture according to the first to fifth aspects of the present invention.

That is, the present invention relates to a polyhydric alcohol (A) having 2 to 8 hydroxyl groups, an alkyl group having 6 to 36 carbon atoms,
A substituted succinic acid having an alkenyl group, an aralkyl group or an aralkenyl group or a substituted succinic anhydride (hereinafter referred to as
A polyhydric alcohol-substituted succinic ester with a substituted succinic acid (B) such as "substituted succinic acid (anhydride)", or an ammonium salt, lower amine salt, sodium salt of the polyhydric alcohol-substituted succinic ester; Salts of alkali metal salts such as potassium and salts of polyvalent metals such as zinc, calcium and magnesium.

According to the constitution of the present invention, there is provided a hardened cement having excellent waterproofness.

The polyhydric alcohol having 2 to 8 hydroxyl groups (A) used for the polyhydric alcohol-substituted succinate in the present invention includes pentaerythritol, saccharose, maltose, glucose, ethylene glycol,
General formula (1) such as glycerin, erythritol, xylitol, arabitol, adonitol, sorbitol, mannitol, iditol, talitol, galactitol, and allitol (Where n represents an integer of 0 to 6). Two or more of these may be used in combination. Among these, preferred are sugar alcohols of the above general formula (1) where n = 4, such as sorbitol, mannitol, iditol, thallitol, galactitol, and allitol, and particularly preferred is sorbitol.

The substituted succinic acid (B) used in the polyhydric alcohol-substituted succinic ester in the present invention is a substituted succinic acid (anhydride) having an alkyl group, an alkenyl group, an aralkyl group or an aralkenyl group having 6 to 36 carbon atoms. It is. For example, alkenyl-substituted succinic acid (anhydride), which is an addition reaction product of α-olefin, internal olefin, or an oligomer such as propylene or butadiene with maleic acid or maleic anhydride, or alkenyl-substituted succinic acid (anhydride) is converted to hydrogen. And aralkyl-substituted succinic acids (anhydrides) and aralkylenyl-substituted succinic acids (anhydrides) derived from olefin compounds having an aromatic ring. Specifically, hexenyl succinic acid, hexyl succinic acid, octyl succinic acid, octenyl succinic acid, nonenyl succinic acid, nonyl succinic acid, decenyl succinic acid, decyl succinic acid, dodecyl succinic acid, dodecenyl succinic acid,
Pentadecenyl succinic acid, pentadecyl succinic acid, hexadecenyl succinic acid, hexadecyl succinic acid, octadecenyl succinic acid, octadecyl succinic acid, (1-octyl-2-decenyl) succinic acid, (1- Hexyl-2-octenyl) succinic acid and the like and anhydrides thereof.
Among them, the substituted succinic acids (B) having an alkyl group or an alkenyl group having 10 to 16 carbon atoms are more preferable in view of the waterproof effect.

When the number of carbon atoms of the substituent of the substituted succinic acids (B) in the present invention is less than 6 or more than 36, there is another effect in terms of waterproofness of the cured cement composition.

In the present invention, the polyhydric alcohol-substituted succinic acid ester is a polyhydric alcohol-substituted succinic acid half ester in which one of the two carboxyl groups of the substituted succinic acid is esterified by the polyhydric alcohol (A). Alternatively, in the case of salts of the polyhydric alcohol-substituted succinic acid half ester, a particularly preferable waterproofing effect can be obtained.

The cement admixture in the present invention may be a resin or a fine powder of 100% of the active ingredient of a polyhydric alcohol-substituted succinic acid ester or a salt of a polyhydric alcohol-substituted succinic acid ester, or a polyhydric alcohol-substituted succinic acid ester. It is used in the form of an aqueous dispersion of a metal salt, an ammonium salt, or a lower amine salt, or an aqueous dispersion in which a polyhydric alcohol-substituted succinate or a salt of a polyhydric alcohol-substituted succinate is dispersed in water with an emulsifier. In particular, a resin containing 100% of the active ingredient of the cement admixture or a fine powder obtained by pulverizing the resin is preferred from the viewpoint of reduction of distribution cost and the like.

The method of using the cement admixture in the present invention is not particularly limited, and includes, for example, a method of previously mixing with the cement, a method of simultaneously adding to the cement composition at the time of kneading, and a method of further adding to the cement composition once kneaded. There are methods.

The type of cement to which the cement admixture according to the present invention can be applied is not particularly limited, and various types of portland cement, such as ordinary, fast and super fast, and blast furnace slag, silica and fly ash are mixed with these portland cements. Mixed cement, alkali cement, etc., and further, alumina cement mainly composed of calcium aluminate.

The aggregate for cement to which the cement admixture of the present invention can be blended and used is not limited as long as it is usually mixed for producing mortar, concrete, cement molded product and the like. , For example, sand, gravel, crushing, crushed stone, slag aggregate, bar light,
Examples include natural lightweight aggregates, ceramics, concrete waste, pulp, synthetic and natural various fibers, and the like.

The amount of the cement admixture used in the present invention is determined by the type of hardened cement and the required degree of waterproofing.
1 to 5% by weight is used, and a frequently used example is 0.2 to 1% by weight.

The cement admixture of the present invention can be used in combination with other known cement admixtures or admixtures.
For example, AF agent, water reducing agent, flow agent, curing accelerator, setting retarder, separation reducing agent, polymer admixture, coloring agent, foaming agent,
Water retention agents, thickeners, rust inhibitors, fine agents, cracking agents, swelling agents, dispersants, glass fibers, high-speed slag fine powder, fly ash, silica fume and the like can be used in combination.

The cement admixture of the present invention provides a hardened cement having excellent waterproofness.

The following effects can be expected by imparting excellent waterproofness to the cured cement. First, in order to prevent water penetration, water leakage is prevented, and deterioration of the hardened cement is prevented. Secondly, since water does not penetrate, the cement hardened body can prevent water from penetrating and freezing in the winter season, causing volume expansion and cracking due to freezing. Third, because of its excellent waterproofness, the movement of water containing calcium ions inside the hardened cement body to the surface is reduced, and carbon dioxide in the air and calcium hydroxide react on the surface and are generated. The effect of suppressing efflorescence can be expected. 4th
In addition, since the movement of water is reduced, the water in the center of the hardened cement is confined, and the hydration reaction is sufficiently performed. Further, when the AE water reducing agent is used, the evaporation and drying of the water are too fast for the hydration reaction. The trouble that required water decreases is eliminated, the construction can be performed with a small amount of water, and good strength can be obtained.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The typical embodiments of the present invention are as follows.

Preparation of cement admixture: A predetermined amount of sorbitol and a predetermined amount of substituted succinic acids were charged into a reaction vessel equipped with a stirrer, a thermometer, a distilling tube, and a nitrogen introducing tube.
The mixture was heated to about 150 ° C. and reacted at the same temperature for 3 to 6 hours to obtain a polyhydric alcohol-substituted succinate.

Preparation of hardened cement: 100 parts of Portland cement, a predetermined amount of the above-mentioned polyhydric alcohol-substituted succinate and a predetermined amount of water were mixed in a mixer for 10 minutes.
After kneading for 10 minutes, the resulting kneaded material is placed in a mold (length 11 mm ×
(59 mm wide x 94 mm deep), and after curing for 24 hours, remove from the mold and cure for 3 days at room temperature, then 80 ° C
For 2 hours, and then allowed to stand for 2 days to obtain a hardened cement.

Evaluation of performance of cured cement: Test method for waterproofness. The cured cement body is immersed in water, and after 2 hours, 4 hours, 8 hours, 24 hours, 48 hours, and 120 hours, excess water is wiped off and the weight is measured. Water absorption). F: Weight before immersion in water (g) G: Weight after immersion in water (g)

[0031]

EXAMPLES The present invention will be described in more detail with reference to Preparation Examples, Examples and Comparative Examples below, but the present invention is not limited to these Examples. "Parts" indicates parts by weight, and "parts" indicates parts by weight.

Preparation of cement admixture: [Preparation Example 1] 45.5 g (0.25 mol) of sorbitol and dodecenyl succinic anhydride were placed in a reaction vessel equipped with a stirrer, a thermometer, a distilling tube, and a nitrogen introducing tube. 266 g (1 mol) were charged and heated to 150 ° C. under a nitrogen stream and reacted at the same temperature for 5 hours. The softening point was 65 ° C., the acid value was 198, and the brown-brown transparent polyhydric alcohol-substituted succinic ester 311.
5 g were obtained.

[Preparation Example 2] A reaction vessel equipped with a stirrer, a thermometer, a distilling tube, and a nitrogen introducing tube was charged with 91 g (0.5 g) of sorbitol.
Mol) and 266 g (1 mol) of dodecenylsuccinic anhydride
And heated to 150 ° C under a nitrogen stream, and
After reacting for 57 hours, the softening point is 57 ° C, the acid value is 154, and the appearance is 357 g of brown-brown transparent polyhydric alcohol-substituted succinic ester.
I got

[Preparation Example 3] 100 g of the polyhydric alcohol-substituted succinate obtained in Preparation Example 1 was charged into a reaction vessel equipped with a stirrer, a thermometer and a condenser, and a 4.7% aqueous sodium hydroxide solution 274 was added. 0.5g saponified and solid content 30%
Thus, 374.5 g of a sodium salt of a polyhydric alcohol-substituted succinic acid ester was obtained. 53.6 g of calcium chloride and 264 water in a reaction vessel equipped with another stirrer, thermometer and cooling tube
g, and the whole amount of the sodium salt of the polyalcohol-substituted succinic ester having a solid content of 30% prepared above was added to the aqueous solution stirred and dissolved, and reacted at a temperature of 60 ° C. for 2 hours to react with the polyalcohol-substituted succinic ester. A suspension of the calcium salt was obtained. Next, the mixture was filtered under reduced pressure through a No. 3 quantitative filter paper using a Buchner funnel, washed and dried with warm air at a temperature of 60 ° C. for 24 hours to obtain a white fine powder having a softening point of 250 ° C.

[Preparation Example 4] 200 g of the polyhydric alcohol-substituted succinate obtained in Preparation Example 2 was charged into a reaction vessel equipped with a stirrer, a thermometer, and a condenser, and dissolved at a temperature of 150 ° C. Calcium hydroxide aqueous solution 30.3
g over 30 minutes, and water was allowed to flow out of the system.
After reacting for an hour, a brown opaque resin having a softening point of 94 ° C. was obtained.

[Preparation Example 5] 91 g (0.5 g) of sorbitol was placed in a reaction vessel equipped with a stirrer, a thermometer, a distilling tube, and a nitrogen introducing tube.
Mol) and 284 g (1 mol) of stearic acid, heated to 250 ° C. under a nitrogen stream and reacted at the same temperature for 6 hours to obtain a stearic acid ester 35 of a polyhydric alcohol having an acid value of 7.
7 g were obtained.

Example 1 Portland Cement 100
Parts, 0.5 part of the cement admixture obtained in Preparation Example 1 and 37 parts of water were kneaded for 10 minutes using a mixer, and the obtained kneaded material was placed in a mold (length 11 mm × width 59 mm × depth 94).
mm), remove from the form after curing for 24 hours,
Cured at room temperature for days. Next, after drying at 80 ° C. for 2 hours, the mixture was allowed to stand for 2 days to obtain a hardened cement.

Example 2 The procedure of Example 1 was repeated, except that the cement admixture of Preparation Example 2 was used instead of the cement admixture obtained in Preparation Example 1. A cured product was obtained.

Example 3 The cement of Example 3 was prepared in the same manner as in Example 1 except that the cement admixture of Preparation Example 3 was used instead of the cement admixture obtained in Preparation Example 1. A cured product was obtained.

Example 4 The cement of Example 4 was prepared in the same manner as in Example 1 except that the cement admixture of Preparation Example 4 was used instead of the cement admixture obtained in Preparation Example 1. A cured product was obtained.

Comparative Example 1 A comparative example was prepared in the same manner as in Example 1 except that the cement admixture obtained in Preparation Example 5 was used instead of the cement admixture obtained in Preparation Example 1. Thus, a cement hardened product of No. 1 was obtained.

Comparative Example 2 In Example 1, sorbitan tristearate (trade name: Boem S-60, RIKEN Vitamin Co., beads) was used in place of the cement admixture obtained in Preparation Example 1. A cured cement of Comparative Example 2 was obtained in the same manner as in Example 1 except for the fact that the cement was not used.

Comparative Example 3 A cured cement of Comparative Example 3 was prepared in the same manner as in Example 1 except that calcium stearate (powder) was used instead of the cement admixture obtained in Preparation Example 1. I got

Comparative Example 4 The cement of Comparative Example 4 was prepared in the same manner as in Example 1 except that 2 parts of calcium stearate (powder) was used instead of the cement admixture obtained in Preparation Example 1. A cured product was obtained.

Evaluation of performance of hardened cement body: The waterproofness of the hardened cement bodies of Examples 1 to 4 and Comparative Examples 1 to 4 was evaluated according to the embodiment. Table 1 shows the results.

[0046]

[Table 1] Performance evaluation of hardened cement

[0047]

Industrial Applicability The cement admixture of the present invention imparts excellent waterproofness to a hardened cement body and suppresses water leakage, efflorescence, and improves durability and strength.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C04B 111: 27 C04B 111: 27

Claims (6)

[Claims] 1. A polyhydric alcohol-substituted succinic ester obtained by esterifying a polyhydric alcohol (A) having 2 to 8 hydroxyl groups with a substituted succinic acid (B) and / or the polyhydric alcohol substitution Cement admixture consisting of succinate salts. 2. The polyhydric alcohol having 2 to 8 hydroxyl groups (A) is represented by the general formula (1) The cement admixture according to claim 1, which is a polyhydric alcohol represented by the formula (wherein, n represents an integer of 0 to 6). 3. The polyhydric alcohol (A) is represented by the following formula (2) The cement admixture according to claim 1, which is a polyhydric alcohol represented by the formula: 4. The substituted succinic acid (B) has 6 to 36 carbon atoms.
The cement admixture according to any one of claims 1 to 3, which is a substituted succinic acid having an alkyl group or an alkenyl group. 5. A polyhydric alcohol-substituted succinic ester obtained by esterifying 1 mol of a substituted succinic acid (B) to 1 mol of a hydroxyl equivalent to 1 mol of a polyhydric alcohol having 2 to 8 hydroxyl groups (A). The cement admixture according to any one of claims 1 to 4, comprising a salt of the succinic acid ester substituted with the polyhydric alcohol. 6. A method for producing a hardened cement, comprising the cement admixture according to claim 1 in an amount of 0.1 to 5% by weight based on the cement.