JPH06157099A - Cement composition - Google Patents

Abstract

PURPOSE:To provide a cement composition prolonged in pot-life, obtainable in appropriate curing time, and improved in fluidity and mechanical strength developability. CONSTITUTION:The cement composition comprises calcium aluminate, polymethacrylic acid compound and boric acid compound (and carbonate and/or carboxylic acid compound). Thus, the essential functions required for cement, which have not been attained in conventional products, (esp. longer pot-life, appropriate curing time, good fluidity and mechanical strength developability) can adequately be satisfied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cement composition, and more specifically, a cement composition capable of extending the pot life, obtaining an appropriate setting time, and ensuring good fluidity and strength development. It relates to a composition.

The cement composition of the present invention is used in the field of refractory materials such as refractory concrete and refractory castables.
It can be widely used in the fields of civil engineering and building materials.

[0003]

2. Description of the Related Art Conventionally, in order to extend the pot life of alumina cement, obtain an appropriate curing time, and secure good fluidity and strength development, saccharides, carboxylic acids, phosphoric acids, Alumina cement that uses a curing modifier for alumina cement such as boric acid and the like has been proposed (H
IGH-ALUMINA CEMENTS AND CONCRETES TDROBSON P129-
133 issued in 1962).

However, this alumina cement is
There was a problem that the pot life could not be secured and the fluidity and strength development were lacking.

[0005] Further, an alumina cement containing a setting modifier composed of citric acid, tartaric acid, and a sulfonic acid type anionic surfactant in combination, an alumina cement containing a setting modifier composed of hydroxycarboxylic acid and an inorganic carbonate, water-soluble Of polyacrylic acid or a salt thereof and an alkali metal carbonate and / or a hydroxycarboxylic acid or a salt thereof in combination with alumina cement, a water-soluble polymethacrylic acid or a salt thereof, a methacrylic acid-acrylic acid copolymer or a salt thereof, ,
Alumina cement containing an alkali metal carbonate and / or a hydroxycarboxylic acid or a salt thereof, and
Alumina cement and the like in which a dispersant comprising a water-soluble polyacrylic acid and / or polymethacrylic acid, a hydroxycarboxylic acid, and an inorganic carbonate is also used have been proposed (JP-A-49-52216 and JP-A-50). -28090, JP 55-7
5947, JP-A-55-75948, and JP-A-55-121
No. 933 publication).

However, these are also those which are sufficiently satisfied with the functions originally required for the alumina cement, in particular, the functions of ensuring a long pot life and ensuring an appropriate hardening time and good fluidity and strength development. Was not.

That is, when the pot life is extended and the fluidity is improved, the curing time is delayed and the strength development is deteriorated. On the other hand, when an appropriate curing time is secured and strength development is attempted to be improved, there is a problem that the fluidity is poor and the pot life is shortened.

[0008] In recent years, constructions have become larger and more irregular in shape, and it has been difficult to meet the demands of the prior art because it is required to secure a pot life and further improve fluidity.

As a result of intensive studies to solve these problems, the inventor of the present invention can obtain a long working life without impairing the fluidity by combining specific materials,
The present invention has been completed based on the finding that an appropriate curing time and excellent strength development can be secured.

[0010]

That is, the present invention is a cement composition containing calcium aluminate, polymethacrylic acid, and boric acid, and calcium aluminate, polymethacrylic acid, boric acid, and A cement composition containing a carbonate and / or a carboxylic acid.

The present invention will be described in detail below.

The calcium aluminate according to the present invention refers to alumina as a raw material, bauxite, aluminum residual ash,
Purified alumina such as Bayer alumina, fused alumina, and sintered alumina is used as a calcia raw material using limestone, calcium carbonate, quick lime, calcium hydroxide, and the like.
The hydraulic mineral obtained by melting and / or firing in an electric furnace, a reverberatory furnace, an open furnace, a converter, a rotary kiln, etc. is blended in a ratio such that a predetermined mineral is produced, and a ball mill,
It is obtained by pulverizing with a pulverizer such as a tube mill, a vibration mill, a roller mill, a jet mill, and a tower mill.

The mineral composition of calcium aluminate is Ca
When O is C and Al ₂ O ₃ is A, usually C ₅ A ₃ , C ₃ A, CA, C
_It is a mineral mainly composed of hydraulic calcium aluminate represented by ₁₂ A ₇ , C ₃ A ₅ , and CA ₂ , and both crystalline and amorphous can be used.

Although the mineral composition of calcium aluminate is not particularly limited, CA and C ₁₂ A ₇ are mainly contained, and C
The production ratio of A to C ₁₂ A ₇ is preferably in the range of C ₁₂ A ₇ /CA=0.1 to 10 in terms of diffraction intensity ratio which is a peak ratio by powder X-ray diffraction analysis, and in O.3 to 5 More preferably,
The range of 0.5 to 3 is most preferable because it shows an appropriate curing time and excellent strength development. If the diffraction intensity ratio is less than 0.1, the curing time tends to be delayed, while if it exceeds 10, there is a possibility that a long pot life and good fluidity cannot be secured.

The term "diffraction intensity ratio" as used herein refers to the diffraction intensity when X-rays of Cu-Kα rays are irradiated, and the crystal lattice number d value of CA is 4.
67 Å and d value of C ₁₂ A ₇ is 4.89 Å.

Method for producing calcium aluminate of the present invention
Is not particularly limited, for example, CA and C₁₂A₇
The production ratio of C₁₂A₇CA to be in the range of / CA = 0.1-10
And C₁₂A ₇CA and C may be manufactured separately and mixed.₁₂A₇To
It is also possible to manufacture all at once so that the above production ratio is achieved.
It

Particularly, it is preferable to use the calcium aluminate produced by the calcination method because the strength development is excellent.

The mixing ratio of the raw material in the case of producing the firing method, CaO 20-60 percent by weight, Al is preferably ₂ O ₃ is 80 to 40%, CaO is 30-40%, the Al ₂ O ₃ 70-60% is more preferable.

The calcining temperature of calcium aluminate is preferably 1,000 to 1,600 ° C, more preferably 1,200 to 1,500 ° C.

The calcium aluminate of the present invention contains, as impurities, 2CaO.Al ₂ O ₃ .SiO ₂ , 4CaO.Al ₂ O ₃ .Fe ₂ O ₃ and C.
It is possible to use those containing aO ・ TiO _2, etc., but when using calcium aluminate as castable,
Other than CaO and Al ₂ O ₃ , for example, SiO ₂ , TiO ₂ , Fe ₂ O ₃ , and M
Impurities such as gO may cause shrinkage at high temperature and generate low melting point compounds. Therefore, the content of these impurities is preferably small.

The particle size of calcium aluminate is preferably fine because it is excellent in fluidity and strength development.
As measured by the Boolean method specified in 2521, the specific surface area is preferably at least 3,000 cm ² / g, more preferably at least ^{4,000cm 2 / g, 6,000cm 2 /} g or more is most preferred.

The average particle size of calcium aluminate is preferably 20 μm or less, more preferably 5 μm or less.
The smaller the average particle diameter is, the more thixotropic high fluidity can be exhibited when kneading with water and used, which is preferable.

The polymethacrylic acid according to the present invention includes polymethacrylic acid or its alkali salt, methacrylic acid or its alkali salt, methacrylic acid or its alkali salt copolymer, and methacrylic acid ester synthetic resin. .

The polymethacrylic acid is preferably anionic when dissolved in water, and it is important that the pH of its aqueous slurry is neutral to alkaline, and
The use of polymethacrylic acids with a pH in the range 7-12 is preferred.

Examples of alkali salts of polymethacrylic acid include sodium salt, potassium salt, calcium salt and the like. The pot life is lengthened and an appropriate curing time is obtained to improve fluidity and strength development. The use of sodium salts is preferred for such reasons.

If the degree of polymerization of the polymethacrylic acid is too large, the flow value tends to be small at the time of kneading with calcium aluminate and the fluidity tends to be low, which is not preferable, and about 50 to 100,000 is preferable.

In the present invention, the polymethacrylic acid is preferably a powder type because it can be premixed with calcium aluminate in advance and the labor required for blending at the time of construction can be reduced.

The powdery polymethacrylic acid can be produced by drying a liquid product with a dryer such as a spray dryer.

The boric acid according to the present invention is boric acid or its alkali salt. Here, boric acid is also known as boric acid, orthoboric acid, or orthoboric acid, and H ₃
It is also possible to use those represented by the chemical formula of BO ₄ and containing pyroboric acid, tetraboric acid, or metaboric acid.

The method for producing boric acid is not particularly limited, but usually, sulfuric acid is added to the original ore of boric acid to decompose it by heating, and the generated boric acid is liberated, separated and extracted, and then purified. can get.

The alkali salt of boric acid is a sodium salt,
And potassium salts, of which sodium salts and potassium salts are preferably used, and any of the water-containing compounds and anhydrous compounds thereof can be used.

The particle size of boric acid is preferably as fine as possible so that it can be easily dissolved in water when mixed with calcium aluminate.

Further, the purity of boric acid is not particularly limited, but it is possible to use boric acid which is currently industrially refined, and bo ₄ content in boric acid is about 80%. The use of the above is preferred.

As the carbonate according to the present invention, any of inorganic carbonates can be used, but alkali carbonates such as sodium carbonate, potassium carbonate, calcium carbonate, sodium hydrogen carbonate and potassium hydrogen carbonate can be used. Preferably, any of its hydrated salt and anhydrous salt can be used.
Of these, use of sodium carbonate is preferred, and JISK
It is possible to use sodium carbonate specified in 1201, JIS K 8624, and JIS K 8625.

The particle size of the carbonate is preferably as fine as possible so that it can be easily dissolved in water when mixed with calcium aluminate, preferably 100 mesh or less, more preferably 200 mesh or less.

The purity of the carbonate is not particularly limited, and it is possible to use an industrially refined carbonate at present, and the purity of the desired carbonate is about 80% or more. Use is preferred.

The carboxylic acids according to the present invention are oxycarboxylic acids or alkali salts thereof, and specific examples thereof include citric acid, tartaric acid, succinic acid, lactic acid, and gluconic acid or alkali salts thereof.

Examples of alkali salts of carboxylic acids include sodium salt, potassium salt, calcium salt and the like. Among these, it is preferable to use citric acid or its alkali salt, especially sodium citrate or potassium citrate.

The particle size of the carboxylic acid is preferably as fine as possible so that it can be easily dissolved in water when mixed with calcium aluminate, preferably 100 mesh or less, more preferably 200 mesh or less.

The purity of the carboxylic acids is not particularly limited, but currently industrially purified carboxylic acids can be used, and the purity of the target carboxylic acids is about 80% or more. Use is preferred. Above all,
Use of citric acid or its salt whose impurity is less than 0.05% or citric acid or its salt whose pH of 1% aqueous solution is 7 to 10 at 20 ° C is long working life. More preferable.

The mixing ratio of each of the above materials is 10 to 300 parts by weight of boric acid to 100 parts by weight of polymethacrylic acid, and 1 part of boric acid to 100 parts by weight of polymethacrylic acid.
0 to 200 parts by weight and 10 to 200 parts by weight of carbonate, and 100 to 100 parts by weight of polymethacrylic acid, 10 to 100 parts by weight of boric acid and 5 to 50 parts by weight of carboxylic acid, and further polymethacrylic acid. 10 to 100 parts by weight of boric acid, 40 to 100 parts by weight of carbonate, and 5 to 50 parts by weight of carboxylic acid are preferable to 100 parts by weight, and 20 to 100 parts by weight of boric acid to 100 parts by weight of polymethacrylic acid. Furthermore, with respect to 100 parts by weight of polymethacrylic acid, 20 to 100 parts by weight of boric acid and 50 to 100 parts by weight of carbonate, and 20 to 50 parts by weight of boric acid to 100 parts by weight of polymethacrylic acid. Parts and carboxylic acids 10
-30 parts by weight, more preferably 20 to 50 parts by weight of boric acid, 50 to 80 parts by weight of carbonate, and 10 to 30 parts by weight of carboxylic acid to 100 parts by weight of polymethacrylic acid.

Among them, a combination of sodium polymethacrylate and boric acid of sodium borate and / or potassium borate, and sodium polymethacrylate and borate of sodium borate and / or potassium borate. , A combination of sodium carbonate and / or potassium carbonate carbonate, and citric acid and / or sodium citrate citric acid are preferable, and the combination of sodium salts is practical from the viewpoint of easy availability.

Outside this range, when compounded with calcium aluminate, the pot life, curing time, fluidity, strength development, etc. cannot be balanced, and the pot life is shortened or the curing time is delayed. Or, it tends to lack liquidity.

Then, polymethacrylic acid and boric acid,
Or polymethacrylic acid and boric acid, carbonate and / or
Alternatively, the amount of the mixture of carboxylic acids used is preferably 0.1 to 10 parts by weight, more preferably 0.5 to 5 parts by weight, based on 100 parts by weight of calcium aluminate. If it exceeds 10 parts by weight, the tendency for retardation of curing becomes strong, and if it is less than 0.1 part by weight, the pot life and fluidity tend to be shortened.

An intermediate temperature range when the cement composition of the present invention is used in applications requiring high fire resistance and high corrosion resistance,
That is, in order to obtain high strength near 700 to 1,200 ° C, α-
It is preferable to further add alumina.

Here, the α-alumina is a product obtained by firing aluminum hydroxide obtained by purifying bauxite by a Bayer process or the like in a firing facility such as a rotary kiln, and is a Bayer alumina, a readily sinterable alumina, or It is called calcined alumina or the like.

The α-alumina has a degree of α conversion of preferably 70% or more, more preferably 90% or more, and most preferably 95% or more because it has excellent high temperature strength and small shrinkage at high temperature.

The Al ₂ O ₃ content of α-alumina is 95%.
The above is preferable, and 99% or more is more preferable.

The content of Na ₂ O in α-alumina is 1.0%.
The following is preferable, and 0.5% or less is more preferable.

[0050] Further, the measured specific surface area is preferably 0.1 to 100 m ² / g by a BET method by nitrogen gas adsorption of α- alumina, more preferably ^{0.5~20m 2 / g, 2~10m 2 /} g is most preferred.

Further, it is preferable to use those obtained by pulverizing alumina particles so that the average particle diameter becomes 0.5 to 10 μm.

Here, the alumina should be pulverized to have a particle size smaller than the particle size of the α crystals constituting the alumina particles so that workability, pot life, and high temperature calcination strength when the cement composition of the present invention is used are secured. It is preferable from the viewpoint of the above.

As a method of blending α-alumina into the cement composition of the present invention, a method of mixing and crushing with a Nauta mixer, a pan mixer, a corn blender, etc., after weighing, ball mill, tube mill, vibration A method of mixing and pulverizing with a pulverizer such as a mill, a roller mill, and a tower mill, or after pulverizing the alumina of the present invention alone with a pulverizer, a material such as calcium aluminate pulverized to a predetermined particle size with a mixer is mixed. Methods and the like.

The amount of α-alumina is preferably 5 to 500 parts by weight, more preferably 20 to 300 parts by weight, based on 100 parts by weight of calcium aluminate, since the curing strength and the dry strength are less likely to decrease. If it is less than 5 parts by weight, the sinter strength at high temperature firing will be insufficient and the effect of improving fire resistance will be small, and if it exceeds 500 parts by weight, the curing strength and dry strength will tend to decrease.

Further, in the present invention, polyacrylic acids can be used in combination for the purpose of extending the pot life and improving the fluidity.

Here, the polyacrylic acids are polyacrylic acid, acrylic acid, and derivatives of acrylic acid or their alkali salts, and specifically, polyacrylic acid or its alkali salts, acrylic acid or its salts. Alkaline salt,
And a polyacrylic acid ester copolymer or an alkali salt thereof. Further, it is preferable to use a cross-linked branched type as the copolymer.

As the alkali salt of polyacrylic acid,
Although sodium salts, potassium salts, calcium salts and the like can be used, it is preferable to use the sodium salt because it is easily available.

In the present invention, it is particularly preferable to use sodium polyacrylate. Among them, a water-soluble polymer having a low degree of polymerization and having a solid content of 95% or more and a concentration of 40% is a slurry at 25 ° C. It is preferable to use a soluble polymerization type having a viscosity of 10,000 cps or less from the viewpoint of improving the fluidity of the cement.

The viscosity of the aqueous slurry can be measured by a B-type viscometer and represents the degree of polymerization. The higher the degree of polymerization, the higher the viscosity tends to be.
It is preferable to use one having a viscosity of 0 to 2,000 cps.

In the present invention, the ionicity and pH of the aqueous slurry of polyacrylic acid are not particularly limited, but in order to obtain greater fluidity when blended with calcium aluminate, polyacrylic acid is It is preferable that the pH of the 1% aqueous slurry at 25 ° C. is anionic, and the pH is neutral to alkaline.
The range of 7.5 to 11 is more preferable.

The mixing ratio of the polyacrylic acid should be appropriately determined depending on the type of calcium aluminate and the desired properties required, but usually, the polyacrylic acid is added to 100 parts by weight of the polymethacrylic acid of the present invention. 200
The amount is preferably not more than 100 parts by weight, more preferably not more than 100 parts by weight. When a large amount of polyacrylic acid is added, the curing time tends to be delayed when mixed with calcium aluminate.

Further, in the present invention, each of the above materials or a mixture thereof is dried or lightly baked at a temperature of 100 to 300 ° C. for 30 minutes or more, preferably 60 minutes or more. It is preferable because it improves the fluidity when blended with a nate, especially those treated at 150 to 200 ° C. have a long pot life, an appropriate curing time, and good fluidity and strength development. The effect of is remarkable.

The cement composition of the present invention comprises GC-MS,
It can be specified by instrumental analysis such as C ¹³ -NMR, HPLC, and FT-IR, activation analysis and the like.

The method of compounding each material constituting the present invention is not particularly limited, and each material is compounded in a predetermined ratio, and a V type blender, a corn blender, a Nauta mixer, a pan type mixer, Further, it is possible to carry out uniform mixing using a mixer such as an omni mixer, or after mixing at a predetermined ratio, mix and pulverize with a pulverizer such as a vibration mill, a tube mill and a ball mill.

In the present invention, the method of mixing other materials at the time of crushing the calcium aluminate clinker and mixing and pulverizing the same is more effective than the method of post-adding the other material after pulverizing the calcium aluminate clinker. It can be demonstrated and is preferable.

Further, in the present invention, various cement additives such as a water reducing agent, an AE agent and a dispersant, which are usually used for cement, can be used in combination, if necessary.

In addition, when used for refractory applications, it is also necessary to use various types of ultrafine powder such as silica fume and fine alumina with a particle size of about 3 μm or less, and fireproof alumina, magnesia, spinel, chamotte, bauxite, and brick waste. It is also effective to use an aggregate together, and in particular, it is preferable to use a basic aggregate such as magnesia or spinel and / or a refractory aggregate such as alumina or mullite.

[0068]

EXAMPLES The present invention will be described below with reference to examples.

Example 1 As an alumina source, specific surface area 8 m ² / g, Al ₂ O ₃ 99.6%, N
a ₂ O is 0.35% alpha-conversion rate is 96%, Nippon Light Metal Co., alumina having an average particle size of 45 [mu] m, using a trade name "A12", as calcia source, using a commercially available quicklime, in the product, respectively
Blended so that the peak ratio of C ₁₂ A ₇ and CA is 2.0, calcined in a siliconit electric furnace to produce calcium aluminate clinker, crushed with a batch type ball mill and calcium with a Blaine specific surface area of 6,000 cm ² / g. Aluminate d was produced.

A mixture containing the materials shown in Table 1 was mixed with 0.8 part by weight of calcium aluminate d (100 parts by weight), and the mixture was mixed with an omni mixer 10 manufactured by Chiyoda Giken Co., Ltd. for 30 minutes to prepare a cement composition. did. According to the following methods, each physical property of the produced cement composition was measured in a thermostatic chamber at 30 ° C. The results are also shown in Table 1.

<Measurement Method> Fluidity: Using mortar described in JIS R 2521 prepared by mixing 200 parts by weight of Toyoura standard sand, 100 parts by weight of cement composition and 60 parts by weight of water in a kneading pot for 3 minutes. Then, after leaving it for a predetermined time at a predetermined temperature, kneading it for 30 seconds, measuring the spread diameter after 15 taps with a flow table according to JIS R 2521, and measuring the flow value after this predetermined time as fluidity. And Pot life: The prepared mortar was put in a plastic bag, and the time required until the mortar became soft without touching it was defined as the pot life. Curing time: A small amount of the prepared mortar was transferred to a poly beaker and measured with a platinum resistance thermometer and a dot recorder,
The time required from the water injection to the exothermic peak was defined as the curing time. Compressive strength: The prepared mortar was placed in a mold of 4 × 4 × 16 cm, and the compressive strength after curing for 24 hours was measured with a hydraulic pressure measuring machine. Mineral composition: measured by X-ray diffractometer "RAD-2B" manufactured by Rigaku Corporation. C ₁₂ A ₇ = 4.89Å, C ₃ A = 4.22Å, CA = 4.67Å, and C
Measure the diffraction intensity ratio of A ₂ = 4.44Å.

<Materials used> Calcium aluminate d: CaO 35%, main minerals CA and C ₁₂ A ₇ , C ₁₂ A ₇ / CA
Peak ratio = 2.0 Polymethacrylic acid: Polymethacrylic acid, Nippon Pure Chemical Co., Ltd. polymethacrylic acid: Sodium polymethacrylate, Nippon Pure Chemical Co., Ltd. polymethacrylic acid: Polyammonium methacrylate, Nippon Pure Chemical Co., Ltd. polymethacrylic acid: Poly Sodium methacrylate, manufactured by Nihon Pure Chemical Co., Ltd. Boric acids α: Sodium borate, Ishizu Pharmaceutical Co., Ltd. reagent first-grade boric acid β: Potassium borate, Ishizu Pharmaceutical Co., Ltd. reagent first-grade boric acid γ: Boric acid, Ishizu Pharmaceutical Co., Ltd. Reagent first grade

[0073]

[Table 1]

As is clear from Table 1, the cement composition of the present invention has a long pot life and excellent fluidity, exhibits an appropriate setting time and high strength development, and is superior to conventional products. It has characteristics.

Example 2 Sodium polymethacrylate of polymethacrylic acid 10
Example 1 was repeated except that 0 part by weight and 50 parts by weight of sodium borate α were mixed with 100 parts by weight of various calcium aluminates shown in Table 2. . The results are also shown in Table 2.

<Materials used> Calcium aluminate a: CaO 20%, main minerals CA and CA ₂ , CA ₂ /CA=1.0 calcium aluminate b: CaO 25%, main minerals CA and CA ₂ , CA ₂ /CA=0.3 calcium Aluminate c: CaO 30%, main minerals CA and C ₁₂ A ₇ , C ₁₂ A ₇ / CA
Peak ratio = 0.1 Calcium aluminate e: 35% CaO, main minerals CA and C ₁₂ A ₇ , C ₁₂ A ₇ / CA
Peak ratio = 0.3 Calcium aluminate f: CaO 35%, main minerals CA and C ₁₂ A ₇ , C ₁₂ A ₇ / CA
Peak ratio = 0.5 Calcium aluminate g: CaO 35%, main minerals CA and C ₁₂ A ₇ , C ₁₂ A ₇ / CA
Peak ratio = 1.0 Calcium aluminate h: CaO 35%, main minerals CA and C ₁₂ A ₇ , C ₁₂ A ₇ / CA
Peak ratio = 3.0 Calcium aluminate i: CaO 35%, main minerals CA and C ₁₂ A ₇ , C ₁₂ A ₇ / CA
Peak ratio = 5.0 Calcium aluminate j: CaO 35%, main minerals CA and C ₁₂ A ₇ , C ₁₂ A ₇ / CA
Peak ratio = 10 Calcium aluminate k: 40% CaO, main minerals CA and C ₁₂ A ₇ , C ₁₂ A ₇ / CA
Peak ratio = 50 Calcium aluminate 1: CaO 50%, main mineral C ₁₂ A ₇ Calcium aluminate m: CaO 60%, main mineral C ₁₂ A ₇ and C ₃ A, C ₁₂ A ₇ / C ₃
A peak ratio = 0.2

[0077]

[Table 2]

As is clear from Table 2, even when different calcium aluminates are mixed, the cement composition of the present invention can secure a long pot life and an appropriate curing time, exhibit excellent fluidity and high strength. Shows sex.

Example 3 35 parts by weight of sodium borate of boric acid α and polymethacrylic acid having different pH of aqueous slurry as shown in Table 3
The procedure of Example 1 was repeated except that a mixture of 100 parts by weight was used. The results are also shown in Table 3.

[0080]

[Table 3]

As is clear from Table 3, it is possible to adjust the pot life, curing time, fluidity, and strength development by changing the pH of the polymethacrylic acid.

Example 4 To 100 parts by weight of a mixture of 50 parts by weight of α-alumina and 50 parts by weight of calcium aluminate, 1.6 parts by weight of the mixture used in Example 2 were mixed, and a 15-type vibration manufactured by Kawasaki Heavy Industries Ltd. was used. The cement composition of the present invention was manufactured by mixing and grinding to a predetermined particle size with a mill, and its physical properties were measured. The results are also shown in Table 4. Example 1 was repeated except that the physical properties were measured as follows.
I went the same way.

<Measurement method> Blaine specific surface area: According to the measurement method described in JIS R 2521. Average particle size: Measured with a laser diffraction particle size distribution analyzer “SALD1000 A range” manufactured by Shimadzu Corporation. High temperature strength: 20 parts by weight of cement composition, as aggregate,
Showa Denko Sintered Alumina grain size is 24 parts by weight of 3.36 to 1.68 mm, 16 parts by weight of 1.68 to 0.71 mm, 20 parts by weight of 0.71 to 0.297 mm, and 20 parts by weight of 0.297 mm below, and 8 parts of water. Mix 4 parts by weight and knead for 5 minutes in a mortar mixer.
It was packed in a mold of × 16 cm, cured for 24 hours, and then deframed. Furthermore, the test piece obtained by drying at 110 ° C. for 20 hours and then at 400 ° C. for 3 hours was fired at a predetermined temperature for 3 hours in a silicon knit type electric furnace, and then allowed to cool to room temperature and the compressive strength was measured.

[0084]

[Table 4]

As is clear from Table 4, when the cement composition of the present invention is blended with alumina, the high temperature strength becomes high and the refractory has excellent performance.

Example 5 The procedure of Example 1 was repeated except that 100 parts by weight of polymethacrylic acid, 70 parts by weight of sodium carbonate of carbonate a, and boric acid shown in Table 5 were used. The results are also shown in Table 5.

<Materials used> Carbonate a: Sodium carbonate, Ishizu Pharmaceutical Co., Ltd. reagent grade 1

[0088]

[Table 5]

As is clear from Table 5, the cement composition of the present invention has a long pot life and excellent fluidity, exhibits an appropriate curing time and high strength development, and is superior to conventional products. Have characteristics.

Example 6 Sodium polymethacrylate of polymethacrylic acid 10
Example 1 was repeated except that 0 part by weight, 35 parts by weight of sodium borate of boric acid α, and the carbonate shown in Table 6 were used. The results are also shown in Table 6.

<Materials to be used> Carbonate B: Potassium carbonate, Ishizu Pharmaceutical Co., Ltd. reagent grade 1 Carbonate C: Sodium hydrogen carbonate, Ishizu Pharmaceutical Co., Ltd. reagent 1
Class

[0092]

[Table 6]

As is clear from Table 6, the cement composition of the present invention has a long pot life and excellent fluidity, exhibits an appropriate curing time and high strength development, and is superior to conventional products. Have characteristics.

Example 7 Sodium polyacrylate of polymethacrylic acid 100
Example 2 was carried out in the same manner as in Example 2 except that a mixture of 1 part by weight, 35 parts by weight of boric acid α sodium borate, and 70 parts by weight of carbonate a sodium carbonate was used. The results are also shown in Table 7.

[0095]

[Table 7]

As is clear from Table 7, even when different calcium aluminates are mixed, the cement composition of the present invention can secure a long pot life and an appropriate curing time, exhibit excellent fluidity and high strength. Shows sex.

Example 8 A mixture obtained by mixing 35 parts by weight of sodium borate of boric acid α, 70 parts by weight of sodium carbonate of carbonate a, and 100 parts by weight of polymethacrylic acid having different pH of an aqueous slurry as shown in Table 8. The same procedure as in Example 3 was performed except that The results are also shown in Table 8.

[0098]

[Table 8]

As is clear from Table 8, it is possible to adjust the pot life, curing time, fluidity, and strength development by changing the pH of the polymethacrylic acid.

Example 9 Example 4 was repeated except that the mixture used in Example 7 was used. The results are also shown in Table 9.

[0101]

[Table 9]

As is clear from Table 9, when the cement composition of the present invention is blended with alumina, the high temperature strength becomes high and the refractory has excellent performance.

Example 10 Example 10 was repeated except that 100 parts by weight of polymethacrylic acid, 20 parts by weight of sodium citrate of carboxylic acid A, and boric acid shown in Table 10 were used. The results are also shown in Table 10.

<Materials used> Carboxylic acid A: sodium citrate, Ishizu Pharmaceutical Co., Ltd. reagent grade 1

[0105]

[Table 10]

As is apparent from Table 10, the cement composition of the present invention has a long pot life and excellent fluidity, exhibits an appropriate curing time and high strength development, and is superior to conventional products. Have characteristics.

Example 11 Polymethacrylic Acids Sodium Polymethacrylate 10
Example 1 was repeated except that 0 part by weight, 35 parts by weight of sodium borate of boric acid α, and carboxylic acids shown in Table 11 were blended. The results are also shown in Table 11.

<Materials Used> Carboxylic Acids B: Potassium Citrate, Reagent 1st Grade by Ishizu Pharmaceutical Co., Ltd. Carboxylic Acids C: Citric Acid, Reagent 1st Grade by Ishizu Pharmaceutical Co., Ltd. Carboxylic Acids D: Tartaric Acid, Reagent 1st Grade Carvone by Ishizu Pharmaceutical Co., Ltd. Acids E: Sodium tartrate, Ishizu Pharmaceutical Co., Ltd. reagent first grade Carboxylic acids F: Succinic acid, Ishizu Pharmaceutical Co., Ltd. reagent first grade Carboxylic acids G: Sodium succinate, Ishizu Pharmaceutical Co., Ltd. reagent grade carboxylic acids H: Lactic acid, Ishizu Pharmaceutical Co., Ltd. Reagent 1 carboxylic acids I: Sodium lactate, Ishizu Pharmaceutical Reagent 1
Grade Carboxylic Acids J: Gluconic Acid, Ishizu Pharmaceutical Co., Ltd. Reagent Grade 1 Carboxylic Acids K: Sodium Gluconate, Ishizu Pharmaceutical Co., Ltd. Reagent Grade 1

[0109]

[Table 11]

As is clear from Table 11, the cement composition of the present invention has a long pot life and excellent fluidity, exhibits an appropriate curing time and high strength development, and is superior to conventional products. Have characteristics.

Example 12 Sodium polymethacrylate of polymethacrylic acid 10
Example 2 was carried out in the same manner as in Example 2 except that 0 part by weight, 35 parts by weight of boric acid α sodium borate, and 20 parts by weight of carboxylic acid A sodium citrate were used.
The results are also shown in Table 12.

[0112]

[Table 12]

As is clear from Table 12, even when different calcium aluminates are mixed, the cement composition of the present invention can secure a long pot life and an appropriate curing time, exhibit excellent fluidity and high strength. Can give sex.

Example 13 35 parts by weight of sodium borate of boric acid α, 20 parts by weight of sodium citrate of carboxylic acid A, and 100 parts of polymethacrylic acid having different pH of aqueous slurry as shown in Table 13
The same procedure as in Example 3 was repeated except that a mixture in which parts by weight were mixed was used. The results are also shown in Table 13.

[0115]

[Table 13]

As is clear from Table 13, the pot life, curing time, fluidity and strength development can be adjusted by changing the pH of polymethacrylic acid.

Example 14 Example 14 was repeated except that the mixture used in Example 12 was used. The results are also shown in Table 14.

[0118]

[Table 14]

As is clear from Table 14, when the cement composition of the present invention is blended with alumina, the high temperature strength becomes high and the refractory has excellent performance.

Example 15 Example 1 was repeated except that 100 parts by weight of polymethacrylic acid, 20 parts by weight of sodium citrate of carboxylic acid A, and a mixture containing the materials shown in Table 15 were used. The results are also shown in Table 15.

[0121]

[Table 15]

As is clear from Table 15, the cement composition of the present invention has a long pot life and excellent fluidity, exhibits an appropriate curing time and high strength development, and is superior to conventional products. It has characteristics.

Example 16 Sodium polymethacrylate of polymethacrylic acid 10
Example 1 was repeated except that 0 part by weight, 35 parts by weight of boric acid α sodium borate, 70 parts by weight of carbonate a sodium carbonate, and carboxylic acids shown in Table 16 were used. . The results are also shown in Table 16.

[0124]

[Table 16]

As is clear from Table 16, the cement composition of the present invention has a long pot life and excellent fluidity, exhibits an appropriate curing time and high strength development, and is superior to conventional products. It has characteristics.

Example 17 Polymethacrylic Acids Sodium Polymethacrylate 10
0 parts by weight, 35 parts by weight of boric acid α sodium borate, 70 parts by weight of carbonate a sodium carbonate, and carboxylic acid A
Example 2 was repeated except that a mixture containing 20 parts by weight of sodium citrate was mixed. The results are shown in Table 17.
Also described in.

[0127]

[Table 17]

As is clear from Table 17, even when different calcium aluminates are mixed, the cement composition of the present invention can secure a long pot life and an appropriate curing time, exhibit excellent fluidity and high strength. Can give sex.

Example 18 The same as Example 3 except that 35 parts by weight of sodium borate of boric acid α, 70 parts by weight of sodium carbonate of carbonate a, and 20 parts by weight of sodium citrate of carboxylic acid A were used. went. The results are also shown in Table 18.

[0130]

[Table 18]

As is clear from Table 18, the pot life, the curing time, the fluidity, and the strength development can be adjusted by changing the pH of the polymethacrylic acid.

Example 19 Example 19 was repeated except that the mixture used in Example 17 was used. The results are also shown in Table 19.

[0133]

[Table 19]

As is clear from Table 19, when the cement composition of the present invention is blended with alumina, the high temperature strength becomes high and it has excellent performance as a refractory material.

[0135]

As is clear from the above examples, the cement composition of the present invention has a function originally required for cement, which cannot be achieved by conventional products, especially,
It has a long pot life and can fully satisfy the functions such as appropriate curing time, fluidity and strength development.

Further, it is possible to exert a high fluidity and a pot life extension effect which have not been obtained in the conventional products.

The cement composition of the present invention is used in the field of refractory materials such as refractory concrete and refractory castables.
It can be widely used in the fields of civil engineering and building materials.

Since it has excellent fire resistance and high temperature strength,
Alumina, magnesia, spinel, chamotte, bauxite, silicon carbide, fused silica, zircon, and blended with refractory aggregates such as brick waste, refractory concrete, amorphous castable, and as a refractory such as precast blocks, or, Mix with sand, gravel, crushed stone, etc.,
Furthermore, it can be used as a civil engineering / building material such as concrete and mortar mixed and kneaded with various polymer emulsions and latexes.

Claims (2)

[Claims] 1. A cement composition comprising calcium aluminate, polymethacrylic acid, and boric acid. 2. A cement composition comprising calcium aluminate, polymethacrylic acid, boric acid, and carbonate and / or carboxylic acid.