JPH05319882A - Additive composition for cement material and production of secondary cement product using the same - Google Patents

Abstract

PURPOSE:To produce an additive composition for cement material to prevent the efflorescence of a secondary cement product by mixing an inorg. powder carrying organopolysiloxane into higher fatty alcohols in a specified ratio. CONSTITUTION:Powder quick lime is gradually added to an organopolysiloxane emulsion and slaked, and the slaked lime is dried and crushed to produce an inorg. powder carrying the orgaonpolysiloxane. 0.1 to 2 pts.wt. of the powder is mixed with 1 pts.wt. of higher fatty acids to prepare an additive composition for the cement material. The calcium and aluminum salts of stearic acid and oleic acid are preferably used as the higher fatty acids. 0.1 to 5 pts.wt. of the composition is added to 100 pts.wt. of cement to obtain a secondary cement product excellent in water proofness, and the efflorescence of the secondary product is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition to be added to a cement-based material such as cement or aggregate. More specifically, it is a cement-based composition such as interlocking block, decorative block, concrete walking plate, artificial wood, utility pole, etc. The present invention relates to a composition that imparts waterproofness and anti-whitening property to the next product or joint mortar premix.

[0002]

2. Description of the Related Art Demand for cement-based secondary products has increased due to the ease of construction, and various types and colors of products have been made from the viewpoint of aesthetics and design.

However, these cement-based secondary products are
It is generally known that it has water absorbency and easily produces white efflorescence. In the past, this white flower was not so much emphasized, but in recent years, the urban landscape has been reviewed, and the problem of white flower has come to the forefront.

In particular, for colored products, a slight amount of white flower generated during production or storage causes
In many cases, the desired color varies, and in extreme cases, the commercial value is lost. In addition, cement-based secondary products are applied to parks, promenades, roads, floors, walls of structures, etc., but the water-soluble salts contained in the underlying soil, sand, empty mortar, concrete, etc. In many cases, bleaching occurs on the surface of the secondary product of the system due to leaching and drying, and the treatment thereof requires a great deal of labor and cost and is economically problematic.

Therefore, in order to prevent white sinter, a method of applying a waterproofing agent to the surface of the product and a method of adding the waterproofing agent at the time of manufacturing the product are often used. As the waterproofing agent added in the latter method, higher fatty acids, higher fatty acids such as metal salts of higher fatty acids, and higher fatty acids such as higher fatty acid esters, paraffin emulsions, asphalt emulsions, organopolysiloxane emulsions, organopolysiloxane oils, Various materials such as powders of organopolysiloxanes, composites of organopolysiloxanes and inorganic materials, and mixtures of organopolysiloxanes and surfactants are known.

[0006]

Of these, higher fatty acids are inexpensive, but they cause a chemical reaction in a relatively short time in contact with water, and biodegradation deteriorates the waterproof performance. Although it has high water repellency, it is difficult to be uniformly dispersed even if it is added when kneading the cement material with water, and in the extreme case, there is a problem that it floats on the surface of the kneaded product. Paraffin-based emulsions, asphalt-based emulsions, organopolysiloxane-based emulsions, mixtures of organopolysiloxanes and surfactants, etc. have poor water resistance due to the large amount of emulsifiers used, and also cement-based alkaline water. When it comes into contact with the emulsion, there is a problem that the emulsion is broken or aggregated and it is difficult to uniformly disperse the emulsion. Further, the asphalt-based emulsion has a drawback that it has a black tint.

Even when the organopolysiloxane oil is added, it is not uniformly dispersed and the waterproof property is not good, and if the order of addition is wrong, the cement may not cure at all. The powder of the organopolysiloxane is a solid having strong water repellency and has poor dispersibility when the cement material and water are kneaded. Therefore, not only is the waterproof property poor, but it is also expensive. In addition, a composite of an organopolysiloxane and an inorganic substance improves the compatibility between the organopolysiloxane and water by forming a complex with a hydrophilic inorganic substance, and improves the dispersibility when kneading the cement-based material and water. It is preferable to raise it, but if the addition amount is large, not only the strength of the hardened material of the cement-based material is lowered, but also it is expensive in the manufacturing process,
It also becomes an economic problem.

As described above, the conventional waterproofing agents have various drawbacks, and there has been no excellent waterproofing agent having a sufficient anti-whitening property.

[0009]

The present invention is an additive composition for cementitious materials comprising a higher fatty acid and an inorganic powder carrying an organopolysiloxane, which has low dispersibility of the higher fatty acid and water. The lack of durability and the weakness of strength property and economical efficiency of the cured product of the cement-based material in the case of adding the inorganic substance supporting the organopolysiloxane mutually complement each other. By adding the additive composition for cementitious material of the present invention to the cementitious material, a cementitious secondary product having excellent waterproofness can be obtained. Is prevented from occurring.

The higher fatty acids used in the present invention can be classified into higher fatty acids, metal salts of higher fatty acids, and higher fatty acid esters. Examples of the higher fatty acids include stearic acid, oleic acid, maleic acid, caproic acid, caprylic acid, etc. Examples of metal salts of higher fatty acids include calcium, aluminum, zinc and ammonium salts of stearic acid, oleic acid and the like. As higher fatty acid ester,
Examples include butyl stearate and butyl oleate. These can be used alone or in combination. Among them, metal salts of higher fatty acids are preferably used, and above all,
Calcium salt and aluminum salt are preferred.

The inorganic powder carrying an organopolysiloxane can be prepared by a known method (for example, Japanese Patent Publication No. 53-31896).
And the production method disclosed in JP-B-56-27465). That is, it is obtained by reacting an organopolysiloxane with basic calcium, for example, quicklime is an organopolysiloxane having an average of 0.8 to 1.8 SiC-bonded hydrocarbon groups per silicon atom. It is obtained by digestion with an aqueous emulsion of, and if the product is not in powder form, dried and ground. The SiC-bonded hydrocarbon group of the organopolysiloxane used in the aqueous emulsion may be an alkyl group, an alkenyl group, a cycloalkyl group, a cycloalkenyl group, an aryl group, an aralkyl group, an alkaryl group, and the like, such as a methyl group, 1 to 16 carbon atoms such as ethyl group, propyl group, butyl group, hexyl group, octyl group and decyl group
Alkyl groups of are preferred. Particularly, a methyl group or a phenyl group is preferable. In addition to the SiC-bonded hydrocarbon group, another group may be bonded to the Si atom. Examples of such a group include a hydroxyl group, an alkoxy group having 1 to 4 carbon atoms, and a hydrogen group. .. It is also possible to use mixtures of various organopolysiloxanes.

The blending ratio in the composition of the present invention is 0.1 to 2 parts by weight of the inorganic powder carrying the organopolysiloxane with respect to 1 part by weight of the higher fatty acid, and 0.2 to 1
Parts by weight are preferred. If the amount of the inorganic powder supporting the organopolysiloxane is less than 0.1 part by weight, the uniform dispersibility is lacking, the waterproofing effect is weak, and white bloom may partially occur. On the other hand, if the amount exceeds 2 parts by weight, the strength of the solidified material of the cement-based material decreases, and the price becomes expensive, which is not economically preferable.

The higher fatty acids and the inorganic powder carrying the organopolysiloxane are preferably mixed using a mixer such as a Henschel mixer, a Nauta mixer or a drum mixer.

The composition of the present invention may be added in an amount of 0.1 to 5 parts by weight, preferably 0.5 to 2 parts by weight, based on 100 parts by weight of cement. If the amount is less than 0.1 parts by weight, the waterproof effect may not be sufficiently exerted, and white fluff may occur. If it exceeds 5 parts by weight, the strength of the secondary cement-based product will decrease,
Also, it is not economically preferable.

The composition of the present invention is a cement-based secondary product,
In particular, by adding it during the manufacturing of interlocking blocks, colored decorative blocks, colored concrete walking plates, artificial wood, colored concrete utility poles, etc. that are colored using pigments, the occurrence of white sinter is suppressed during manufacturing and storage, and the color tone is reduced. It is possible to stabilize and reduce the amount of pigment added. Further, even after the construction, the occurrence of white sinter is prevented for a long period of time, and the appearance of the cement-based secondary product is maintained.

[0016]

EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples.

Example 1 500 g of an aqueous emulsion of organopolysiloxane (BSR-50 manufactured by Wacker) was mixed with 20 g of sodium lauryl sulfate (surfactant), and then 500 g of powdered quick lime.
Inorganic powder (a) carrying an organopolysiloxane containing 1.1% by weight of water, which is digested while gradually mixing
Got 25 parts by weight of the powder (a) was added to 100 parts by weight of calcium stearate and mechanically mixed with a Henschel mixer to obtain an additive composition for cementitious material of the present invention.

Example 2 100 parts by weight of a commercially available inorganic powder (BS-49 manufactured by Wacker Co., Ltd.) was prepared by mixing an emulsion of organopolysiloxane and powdered quicklime with 100 parts by weight of calcium stearate and digesting and supporting the mixture. The mixture was added and mixed with a Henschel mixer to obtain the additive composition for cement-based materials of the present invention.

Example 3 100 parts by weight of cement, 100 parts by weight of fine aggregate (sand), 3 parts by weight of inorganic pigment (black), and the above Example 1
1 part by weight of the additive composition for cementitious materials obtained in 1. was kneaded with a mixer, and SBR latex (solid content) was added to this.
5 parts by weight and 30 parts by weight of water (including water in the latex) were added and mixed to prepare a color mortar. This 2
A mold having a size of 0 cm × 10 cm and a depth of 5 cm was weighed and filled, and pressure was applied by a pressing machine to mold a color mortar block having a size of 20 cm × 10 cm and a thickness of 3 cm. After removing from the mold, it was cured in the room for 1 week, and various performances were examined.

Example 4 A color mortar block was prepared in the same manner as in Example 3 except that 0.75 parts by weight of the additive composition for cementitious materials obtained in Example 1 was added to 100 parts by weight of cement. And investigated various performances.

Example 5 Except that the additive composition for cementitious material obtained in Example 1 was added in an amount of 1.5 parts by weight to 100 parts by weight of cement,
A color mortar block was obtained in the same manner as in Example 3,
Various performances were investigated.

Example 6 Except that 1 part by weight of the additive composition for cementitious materials obtained in Example 2 was added to 100 parts by weight of cement.
Color mortar blocks were obtained in the same manner as in Example 3, and various performances were examined.

Comparative Example 1 The additive composition for cementitious materials of the present invention was not added at all,
Color mortar blocks were produced in the same manner as in Example 3, and various performances were examined.

Comparative Example 2 A color mortar block was prepared in the same manner as in Example 3 except that 1 part by weight of calcium stearate was added to 100 parts by weight of cement instead of the composition of the present invention, and various performances were obtained. I checked.

COMPARATIVE EXAMPLE 3 In place of the composition of the present invention, 1 part by weight of the inorganic powder (a) carrying the organopolysiloxane obtained in the first half of Example 1 was added to 100 parts by weight of cement. In the same manner as in Example 3 to obtain a color mortar block,
Various performances were investigated.

Table 1 shows the results of examining various performances of the color mortar blocks obtained in Examples 3 to 6 and Comparative Examples 1 to 3. The test methods and evaluation criteria for various performances are as shown below.

[Test Method] 1. Surface appearance After molding and curing a color mortar block, observe the color tone of the block surface. ○: The color is clear. Δ: The color is slightly dull. X: A grayish color. Or white flower is occurring.

2. Water wettability test 0.5 cc of water was gently placed on the surface of the color mortar block, and after 10 minutes, the water remaining on the surface was absorbed with a dry cloth,
Observe the condition of wet marks. A: Water repellency is strong, and no wet marks remain. B: Wet marks remain without spreading. C: There is no water repellency and spreads wet marks.

3. Natural white flower test With the surface of the color mortar block facing up, dip in water to half the thickness of the block and let stand for 1 day. After pulling up from water, it is dried and the surface color tone is observed. ○: The color of the color mortar is not so different from the color before the test. Δ: The color of the block surface is a dull hue. X: White flower is generated and the color becomes grayish.

4. Forced white flower test The surface of the color mortar block is faced up and immersed in a 10% aqueous MgSO ₄ solution for 3 days to a half thickness of the block.
After that, it is dried and the white sinter on the surface is observed. ◯: White sinter does not occur at all. Δ: Slight white fluff occurs, and the whole has a dull color tone. X: White fluff occurs in the whole or in part.

5. Water Absorption Test The side surface of the color mortar block is sealed with an epoxy resin, and the surface is faced downward and immersed in water for 1 cm. After 24 hours, pull up from water, wipe off excess water with a dry cloth, and measure weight. Water absorption amount (g) = [weight after water absorption test]-[weight before water absorption test]

6. Mortar Bending Strength Test After demolding the color mortar block, 20 ± 3 ℃,
It was aged in a thermo-hygrostat at 65 ± 5% RH for 4 weeks. According to JIS-A-1106, this was bent with a span of 9 cm, and the bending strength was determined from the maximum load when broken.

[0033]

[Table 1]

Example 7 Cement 100 parts by weight, fine aggregate 100 parts by weight, inorganic pigment (brown) 3 parts by weight, and composition 1 obtained in Example 1
Part by weight was kneaded by a countercurrent mixer, and then 5 parts by weight of an admixture and 30 parts by weight of water were added and mixed to prepare a color mortar.

Using an interlocking block molding machine, the pre-prepared base layer concrete was weighed and filled into a mold, and vibration compaction was performed to a thickness of 54 mm, and then the surface color mortar of a thickness of 6 mm was obtained. Then, the interlocking block was manufactured by weighing and filling so as to obtain, and pressing with vibration compaction. After curing for 1 day, the surface condition was observed, a natural white flower test and a forced white flower test were carried out. As a result, the color tone was clear and no forced white flower occurred.

When the composition of the present invention was not added, only an interlocking block in which the color was dull and white sinter was generated was obtained.

Example 8 100 parts by weight of white cement, 250 parts by weight of aggregate, 3 parts by weight of inorganic pigment (green), composition 1.5 obtained in Example 2
Part by weight and 50 parts by weight of water were mixed with a mortar mixer to obtain a color mortar.

This color mortar was filled in a mold of 30 cm × 30 cm and height of 60 mm to a thickness of 10 mm, and after applying vibration for 5 seconds, concrete prepared in advance was poured and vibration was tightened to 5 After performing the second treatment, the sheet was cured in a room for 24 hours, then removed from the mold and cured in air for 3 days. A water-repellent color walking plate having a clear color tone and free of white fluff was obtained.

It was observed that white sinter was partially generated during curing when the composition of the present invention was not added.

[0040]

The additive composition for cementitious materials of the present invention imparts excellent waterproofness to the cementitious material. Therefore, in the cementitious secondary product produced by adding the composition of the present invention, The water content does not exude to the surface of the product, and the occurrence of white sinter is prevented for a long time.

Front page continuation (72) Inventor Yuji Shinkai 1 Irifune-cho, Himeji-shi, Hyogo Prefecture, Sumitomo Seika Chemical Co., Ltd. 2nd Research Laboratory (72) Inventor Tatsuo Otani 4-chome, Kitamahama 4-chome, Chuo-ku, Osaka Sumitomo Seiki Kaika Co., Ltd. Osaka head office

Claims (5)

[Claims] 1. An additive composition for a cement-based material, which comprises an inorganic powder carrying higher fatty acids and an organopolysiloxane. 2. The additive composition for cementitious materials according to claim 1, wherein the higher fatty acid is a metal salt of a higher fatty acid. 3. The additive composition for a cementitious material according to claim 1, wherein the inorganic powder carrying the organopolysiloxane is obtained by digesting quicklime with an emulsion of the organopolysiloxane, drying and crushing. 4. The cement system according to claim 1, wherein 0.1 to 2 parts by weight of the inorganic powder supporting the organopolysiloxane is mixed with 1 part by weight of the higher fatty acid. Additive composition for materials. 5. The method according to claim 1, relative to 100 parts by weight of cement.
5. A method for producing a cement-based secondary product, comprising adding 0.1 to 5 parts by weight of the composition according to any one of 1 to 4.