JP3531748B2 - Cement composition - Google Patents

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
Water-soluble polyacrylic acid and / or polymethacrylic acid, hydro-oxy acids, and combination with alumina cement, etc. has been proposed (JP 49-52216 discloses a dispersing agent consisting of inorganic carbonates, Akira JP Duke 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 contrary, 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 provides a polymer
Tacrylic acid 100 parts by weight, polyacrylic acid 10-2
00 parts by weight, 10 to 100 parts by weight of boric acid and carbonate 4
A mixture containing 0 to 100 parts by weight and calcium aluminum
A cement composition containing a cement,
100 parts by weight of phosphoric acid, 10 to 100 polyacrylic acid
Parts by weight, 10 to 40 parts by weight of boric acid, and quenching
Carbohydrates selected from acids, tartaric acid and their alkali salts
A mixture containing 5 to 50 parts by weight of acids and calcium alkane
A cement composition containing minate,
To 100 parts by weight of polymethacrylic acid, polyacrylic acid
10 to 100 parts by weight, boric acid 10 to 50 parts by weight, charcoal
40 to 100 parts by weight of acid salt, citric acid, tartaric acid,
Carvone selected from succinic acid and alkali salts thereof
Mixture containing 5 to 40 parts by weight of acids and calcium aluminum
A cement composition containing a nate .

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.

[0020] Calcium aluminate of the present invention, as an _{impurity, CaO · 6Al 2 O 3,} 2CaO · Al 2 O 3 · SiO 2, 4CaO · Al 2 O 3 ·
Fe ₂ O ₃ , and, it is also possible to use those containing CaO · TiO _2, etc., when using calcium aluminate as castable, other than CaO and Al ₂ O ₃ , for example, SiO ₂ , TiO ₂ ,
Impurities such as Fe ₂ O ₃ and MgO may cause shrinkage at high temperatures and form 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,
It is important that the pH is neutral to alkaline, and it is particularly preferable to use polymethacrylic acid having a pH in the range of 7 to 12.

As the alkali salt of polymethacrylic acid,
Although there are sodium salts, potassium salts, calcium salts and the like, the use of sodium salts is preferable from the viewpoint of prolonging the pot life, obtaining an appropriate curing time, and improving the fluidity and strength development.

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 from the viewpoint that 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 polyacrylic acid according to the present invention is polyacrylic acid, acrylic acid, and a derivative of acrylic acid or an alkali salt thereof, and specifically, polyacrylic acid, acrylic acid, polyacrylic acid ester. A copolymer or an alkali salt thereof or the like, and as the copolymer,
Cross-linked branched type is preferred.

As the alkali salt of polyacrylic acid, it is possible to use sodium salt, potassium salt, calcium salt and the like, but it is preferable to use 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 not used. 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.

In the present invention, the polyacrylic 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 polyacrylic acid can be produced by subjecting a liquid product to a drying treatment 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, the generated boric acid is liberated, separated and extracted, and then purified. can get.

The alkaline 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.

The purity of boric acid is not particularly limited, but currently industrially purified boric acid can be used, and bo ₄ content in boric acid is about 80% or more. It is preferable to use

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 target carbonate is about 80% or more. Use is preferred.

[0044] In the carboxylic acids according to the present invention, Que
Acids, tartaric acid, succinic acid and their alkalis are mentioned.

The 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 it is possible to use industrially purified carboxylic acids, and the purity of the desired 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.

In the present invention, each of the above materials is used, and the amount used is 100 parts by weight of polymethacrylic acid,
10 to 200 parts by weight of polyacrylic acid, 10 to 100 parts by weight of boric acid, 40 to 100 parts by weight of carbonate or 5 to 100 parts by weight of carboxylic acid, and 100 parts by weight of polymethacrylic acid,
Polyacrylic acids 10 to 200 parts by weight, boric acids 10 to 100 parts by weight, carbonates 40 to 100 parts by weight, and carboxylic acids 5 to 50 parts by weight are preferred, polyacrylic acids 20 to 100 parts by weight, boric acids 20 to 50 Parts by weight, carbonates 50 to 80 parts by weight or carboxylic acids 10 to 50 parts by weight, polyacrylic acids 20 to 100 parts by weight.
Parts by weight, boric acid 20 to 50 parts by weight, carbonate 50 to 80 parts by weight,
And 10 to 30 parts by weight of carboxylic acids are more preferable.

Among them, sodium polymethacrylate, polyacrylic acids such as sodium polyacrylate and / or potassium polyacrylate, borate salts of sodium borate and / or potassium borate, and sodium carbonate and potassium carbonate. A combination of one or more selected from the group of alkali carbonates and citric acid, citric acid such as sodium citrate and potassium citrate is preferable, and the combination of sodium salts is practical from the viewpoint of easy availability.

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

Polymethacrylic acid, polyacrylic acid,
The amount of the boric acid and the mixture of carbonate and / or carboxylic acid 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 is less than 0.1 part by weight, the pot life and fluidity will be short, and if it is more than 10 parts by weight, the tendency of delaying the curing time tends to be strong.

An intermediate temperature range when the cement composition of the present invention is used for 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, 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 α-alumina content is 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.

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

[0057] 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 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, it is mixed with a material such as calcium aluminate pulverized to a predetermined particle size with a mixer. Methods and the like.

The blending 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 from the viewpoint that the curing strength and the drying 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, 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, It is also possible to use a mixer such as an omni-mixer for uniform mixing, or after mixing at a specified ratio, mix and pulverize with a pulverizer such as a vibration mill, tube mill, jet mill, roller mill, or ball mill. Is.

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 of 96% and an average particle diameter of 45μm by Nippon Light Metal Co., Ltd. alpha alumina, trade name using "A12", as calcia source, using a commercially available quicklime 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 by a batch type ball mill, and a Blaine specific surface area of 6,000 cm ² / g Of calcium aluminate d was produced.

A mixture containing the various materials shown in Table 1 was prepared.
0.8 parts by weight is mixed with 100 parts by weight of calcium aluminate d, and it is 30 with an Omnimixer 10 type manufactured by Chiyoda Giken Kogyo Co., Ltd.
The mixture was mixed for a minute to prepare a cement composition. 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 Industries polymethacrylic acid: Sodium polymethacrylate, Nippon Pure Chemical Industries polymethacrylic acid: Polyammonium methacrylate, Nippon Pure Chemical Industries polymethacrylic acid: Poly Sodium Methacrylate, Nippon Pure Chemical Co., Ltd. polyacrylic acid a: Sodium polyacrylate, Nippon Pure Chemical Co., Ltd. polyacrylic acid b: Polyacrylic acid, Nippon Pure Chemical Co., Ltd. boric acid α: Sodium borate, Ishizu Pharmaceutical Co., Ltd. Reagent first-grade carbonate I: Sodium carbonate, Ishizu Pharmaceutical Reagent first-grade

[0073]

[Table 1]

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

Example 2 Sodium polymethacrylate of polymethacrylic acid 10
Example 1 was repeated except that 0 part by weight, 50 parts by weight of sodium polyacrylate of polyacrylic acid b, and the materials shown in Table 2 were blended. The results are also shown in Table 2.

<Materials to be used> Boric acids β: potassium borate, Ishizu Pharmaceutical Co., Ltd. reagent first-grade boric acid γ: boric acid, Ishizu Pharmaceutical Co., Ltd. reagent first-grade carbonate b: potassium carbonate, Ishizu Pharmaceutical Co., Ltd. reagent first-grade Carbonate C: Sodium hydrogen carbonate, reagent 1 manufactured by Ishizu Pharmaceutical Co., Ltd.
Class

[0077]

[Table 2]

As is clear from Table 2, the cement composition of the present invention showed a long pot life and an appropriate curing time, excellent fluidity and high strength development, and was superior to the conventional products. It has characteristics.

Example 3 Sodium polymethacrylate of polymethacrylic acid 10
A mixture of 0 parts by weight, 50 parts by weight of polyacrylic acid b sodium polyacrylate, 35 parts by weight of boric acid α sodium borate, and 70 parts by weight of carbonate a sodium carbonate was added to 100 parts by weight of various calcium aluminates. For each part, the same procedure as in Example 1 was carried out except that the ingredients were compounded as shown in Table 3. The results are also shown in Table 3.

<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: CaO 35%, main minerals CA and C ₁₂ A ₇ , C ₁₂ A ₇ / CA
Peak ratio = 0.3 Calcium aluminate f: 35% CaO, 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: CaO 40%, 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

[0081]

[Table 3]

As is clear from Table 3, 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 4 Using a combination of 50 parts by weight of sodium polyacrylate of polyacrylic acid b, 35 parts by weight of sodium borate of boric acid α, and 70 parts by weight of sodium carbonate of carbonate a, the pH of the aqueous slurry was adjusted. Table 3 shows 100 parts by weight of different polymethacrylic acids.
The same procedure as in Example 1 was carried out except that the mixing was carried out as shown in FIG. The results are also shown in Table 4.

[0084]

[Table 4]

As is clear from Table 4, the pot life, fluidity, curability, and strength development can be adjusted by changing the viscosity of polyacrylic acid, that is, the degree of polymerization.

Example 5 Sodium polymethacrylate of polymethacrylic acid 10
A mixture of 0 parts by weight, 50 parts by weight of sodium polyacrylate of polyacrylic acid b, 35 parts by weight of sodium borate of α-borate, and 70 parts by weight of sodium carbonate of carbonate a was added to 50 parts by weight of α-alumina. 100 parts by weight of a mixture of 50 parts by weight of calcium aluminate and 1.6 parts by weight, and mixed and pulverized to a predetermined particle size with a 15-type vibration mill manufactured by Kawasaki Heavy Industries, Ltd. to produce the cement composition of the present invention. Its physical properties were measured. The results are also shown in Table 5. The physical properties were measured in the same manner as in Example 1 except that the following were carried out.

<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.

[0088]

[Table 5]

As shown in Table 5, 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 6 Example 1 was repeated except that 20 parts by weight of sodium citrate of carboxylic acids A and the materials shown in Table 6 were used.
The results are also shown in Table 6.

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

[0092]

[Table 6]

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

Example 7 Polymethacrylic Acids Sodium Polymethacrylate 10
Example 1 was repeated except that 0 parts by weight, 50 parts by weight of sodium polyacrylate of polyacrylic acid b, 35 parts by weight of sodium borate of boric acid α, and the formulation shown in Table 7 were used. The results are also shown in Table 7.

<Materials used> Carboxylic acids B: potassium citrate, reagent primary carboxylic acid manufactured by Ishizu Pharmaceutical C: citric acid, reagent primary carboxylic acid manufactured by Ishizu Pharmaceutical D: tartaric acid, reagent primary carboxylic acid manufactured by Ishizu Pharmaceutical Acids E: Sodium tartrate, reagent primary carboxylic acids manufactured by Ishizu Pharmaceutical F: Succinic acid, reagent primary carboxylic acids manufactured by Ishizu Pharmaceutical G: Sodium succinate, reagent primary carboxylic acids manufactured by Ishizu Pharmaceutical H: Lactic acid, Ishizu Pharmaceutical Reagents manufactured by the company, primary carboxylic acids I: sodium lactate, reagent 1 manufactured by Ishizu Pharmaceutical Co., Ltd.
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

[0096]

[Table 7]

As is clear from Table 7, the cement composition of the present invention showed a long pot life and an appropriate setting time, excellent fluidity and high strength development, and was superior to the conventional products. It has characteristics.

Example 8 Sodium polymethacrylate of polymethacrylic acid 10
Except that a mixture of 0 parts by weight, 50 parts by weight of sodium polyacrylate of polyacrylic acid b, 35 parts by weight of sodium borate of α-borate, and 20 parts by weight of sodium citrate of carboxylic acid A was used. The same procedure as in Example 3 was performed. The results are also shown in Table 8.

[0099]

[Table 8]

As is clear from Table 8, 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 9 The procedure was carried out except that 50 parts by weight of sodium polyacrylate of polyacrylic acid b, 35 parts by weight of sodium borate of α boric acid, and 20 parts by weight of sodium citrate of carboxylic acid A were used. The same procedure as in Example 4 was performed. The results are also shown in Table 9.

[0102]

[Table 9]

As is clear from Table 9, the pot life, fluidity, curability, and strength development can be adjusted by changing the viscosity of polyacrylic acid, that is, the degree of polymerization.

Example 10 Example 5 except that the mixture used in Example 8 was used.
I went the same way. The results are also shown in Table 10.

[0105]

[Table 10]

As shown in Table 10, when alumina is added to the cement composition of the present invention, the high temperature strength becomes high and the cement composition has excellent performance as a refractory.

Example 11 Example 11 was carried out in the same manner as in Example 1 except that the formulation shown in Table 11 was used. The results are also shown in Table 11.

[0108]

[Table 11]

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

Example 12 Sodium polymethacrylate of polymethacrylic acid 10
0 parts by weight, polyacrylic acid b sodium polyacrylate 50 parts by weight, carboxylic acid A sodium citrate 20
The same procedure as in Example 1 was performed except that the parts by weight and the materials shown in Table 12 were used. The results are also shown in Table 12.

[0111]

[Table 12]

As is clear from Table 12, the cement composition of the present invention showed a long pot life and an appropriate curing time, excellent fluidity and high strength development, and was superior to the conventional products. It has characteristics.

Example 13 Polymethacrylic Acids Sodium Polymethacrylate 10
0 parts by weight, 50 parts by weight of sodium polyacrylate of polyacrylic acid b, 35 parts by weight of sodium borate of boric acid α, 20 parts by weight of sodium citrate of carboxylic acid A, and other than using the formulation shown in Table 13 Was performed in the same manner as in Example 1. The results are also shown in Table 13.

[0114]

[Table 13]

As is clear from Table 13, the cement composition of the present invention showed a long pot life and an appropriate curing time, excellent fluidity and high strength development, and was superior to the conventional products. It has characteristics.

Example 14 Sodium polymethacrylate of polymethacrylic acid 10
0 part by weight, 50 parts by weight of sodium polyacrylate of polyacrylic acid b, 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 The procedure of Example 3 was repeated except that the blended mixture was used. The results are also shown in Table 14.

[0117]

[Table 14]

As is clear from Table 14, 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 15 Sodium polymethacrylate of polymethacrylic acid 10
0 parts by weight, 50 parts by weight of sodium polyacrylate of polyacrylic acid b, 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 The same procedure as in Example 4 was repeated except that the formulation was used. The results are also shown in Table 15.

[0120]

[Table 15]

As is clear from Table 15, by changing the viscosity of polyacrylic acid, that is, the degree of polymerization, the pot life,
It is possible to adjust fluidity, curability, and strength development.

Example 16 Example 5 except that the mixture used in Example 14 was used.
I went the same way. The results are also shown in Table 16.

[0123]

[Table 16]

As shown in Table 16, when alumina is added to the cement composition of the present invention, the high temperature strength becomes high and the cement composition has excellent performance as a refractory.

[0125]

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 takes a long pot life, suitable curing time, good liquidity and <br/> strength of onset current properties such as function fully satisfactory.

Since it is excellent in 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.

Further, it is possible to exert the high fluidity and the effect of extending the pot life which were not available in the conventional products.

The cement using the cement composition of the present invention can be widely used in the field of refractories such as refractory concrete and refractory castables, and also in the field of civil engineering / construction materials.

   ─────────────────────────────────────────────────── ─── Continued front page       (56) References JP-A-55-75948 (JP, A)                 JP-A-2-51457 (JP, A)                 JP-A-3-54140 (JP, A)                 JP 58-115052 (JP, A)

Claims (3)

(57) [Claims] 1. 100 parts by weight of polymethacrylic acid, polyamine
10 to 200 parts by weight of acrylic acid, 10 to 100 boric acid
A mixture comprising 40 parts by weight of carbonate and 40 to 100 parts by weight of carbonate;
A cement composition containing calcium aluminate . 2. 100 parts by weight of polymethacrylic acid, polyacetic acid
10-100 parts by weight of acrylic acid, 10-40 parts of boric acid
Parts, and citric acid, tartaric acid and their alkalis
Mixture containing 5 to 50 parts by weight of carboxylic acids selected from salts
And cement containing calcium aluminate
Composition. 3. 100 parts by weight of polymethacrylic acid, polyacetic acid
10 to 100 parts by weight of acrylic acid, 10 to 50 parts by weight of boric acid
Parts by weight, 40-100 parts by weight of carbonate, and citric acid,
Selected from tartaric acid, succinic acid and their alkali salts
A mixture containing 5 to 40 parts by weight of carboxylic acids, and calciu
A cement composition containing mualuminate.