JP2814042B2 - Cementitious composition and product thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cementitious composition having high strength and excellent heat resistance and water resistance, and a product thereof.

[0002]

2. Description of the Related Art The bending strength of a cement product manufactured using hydraulic cement is generally 50 to 100 kgf / c.
For low and m ^2, and have reinforcing bars used as a reinforcing material for a long time. In addition, in order to improve the bending strength of cement products, in recent years, reinforcement has been performed by adding short fibers such as glass fiber or carbon fiber, but the bending strength is also 400 kN.
It rarely exceeds gf / cm ² .

In general, a hardened cement body has a higher strength when the amount of water used for kneading is smaller, and the strength becomes higher as the number of pores contained in the hardened body is smaller. As an example, a hardened cement material having extremely high bending strength without requiring fibers or high compression molding is known (JP-B-59-43431).

[0004] In the hardened cement disclosed in Japanese Patent Publication No. 59-43431, a hydraulic cement water and an aqueous organic polymer are kneaded with a high shear force such as a two-roll mill, and the pores in the hardened cement are reduced. This is due to limitations on dimensions and proportions. However, these hardened cements with improved flexural strength have a problem that they are poor in water resistance, for example, when immersed in water, the strength is remarkably reduced or swells because of the aqueous organic polymer.

[0005] Further, there is an example in which an isocyanate compound is reacted with a hydrophilic group to improve water resistance (Japanese Patent Application Laid-Open No. Sho 63/63).
-206342), since this isocyanate compound has a strong pungent odor and is toxic, there is a problem in working at the time of kneading and molding, or a urethane derivative which is a main reaction product has heat resistance. Was low.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the prior art as described above.
It is an object of the present invention to provide a cementitious composition having high bending strength and excellent properties in water resistance and heat resistance, and a product thereof.

[0007]

In order to achieve the above object, the gist of the present invention is to provide at least one type of hydraulic cement and an alcohol-soluble phenolic resin precursor which is substantially free of water but produces water by polymerization. The cementitious composition containing the body and the cementitious composition, after kneading, molding,
It is in a cementitious product obtained by curing by heating.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, a cementitious composition and a product thereof satisfying the above-mentioned characteristics are obtained by adopting the above-mentioned constitution, and a cementitious product is immersed in water. However, there was almost no decrease in the strength, and conversely, there was a composition showing an increase in the strength, and completed. That is, although water is essentially not present in the composition before the curing process in the present invention, the phenol resin precursor is polymerized and cured by heat treatment of the same composition, and cement is formed by the water generated as a result of the polymerization. Hydration reaction occurs, and a cementitious composition exhibiting high strength and extremely excellent water resistance and heat resistance, and a product thereof can be obtained.

Hereinafter, the present invention will be described in detail. As the hydraulic cement used in the present invention, a conventional cement can be used. Examples include Portland cement (eg, ordinary Portland cement, early-strength Portland cement, moderately heated Portland cement, etc.), mixed cement (eg, blast furnace cement, silica cement, fly ash cement, etc.), special cement (eg, alumina cement, oil well cement, etc.). And various plasters. The hydraulic cement may be used alone, or two or more of the above cements may be used in combination.

[0010] The alcohol-soluble phenolic resin precursor that is polymerized while producing water is formed in consideration of the subsequent moldability.
Adjust the viscosity to the required viscosity with alcohols as appropriate,
Alcohol solutions with a non-volatile content of 40-70% are preferred.
Examples of alcohols in the present invention include methanol, ethanol, propanol, butanol, cyclohexanol, phenol, cresol, ethylene glycol,
A wide range of alcohols such as trimethylene glycol can be used.

The mixing ratio of the phenol resin precursor is as follows:
10 to 60 parts by weight, preferably 12 parts by weight, based on 100 parts by weight of hydraulic cement (when filler is mixed, based on 100 parts by weight of the powdery component obtained by adding filler to hydraulic cement) A range of from 30 parts by weight is good. When the phenolic resin precursor is at most 8 parts by weight, kneading with the hydraulic cement cannot be performed well, and the strength of the cured product will be low. Conversely, when the amount exceeds 60 parts by weight, cracks occur in the cured product and the strength also reaches a plateau, which is not economically preferable.

A hydraulic cement and a phenolic resin precursor,
The kneading of additives and / or fillers added as necessary can be carried out using a conventional mixing device such as an Erich mixer or a spiral mixer. When the blending ratio of the phenolic resin precursor is relatively small, the compressing action,
A mixing device capable of exerting a shearing action or a spatula action is preferred. Examples thereof include a kneader, a wet pan mill, a helical rotor, a roll mill, and a Banbury mixer.

The kneaded cementitious composition is roll-formed, extruded, pressed, or poured into a mold to form a desired size and shape, and then heated to polymerize the phenolic resin precursor. . Heating is generally in the range of 100-300 ° C, preferably 150-250 ° C.
Good range of ° C. The heating causes the phenolic resin precursor to polymerize, and the water produced by the polymerization causes a hydration reaction of the hydraulic cement to provide high strength.

In general, the curing reaction of a phenol resin rapidly proceeds in an acidic region of pH 7 or less, but even in an alkaline region of pH 7 or higher, heating at a temperature of 150 to 250 ° C. for a relatively long time is sufficient. It can be cured. It is known that this curing reaction mainly proceeds by the following model condensation reaction.

[0015] Further, the water generated by the methyleneation reaction rapidly hydrates the hydraulic cement under heating to form a cement hydrate. Through the above process, the strong three-dimensional crosslinked structure of phenolic resin and cement hydrate intersect with each other to form the structure of the cement product through the process described above, achieving high strength. Interpreted as possible.

The cementitious composition of the present invention exhibits high flexural strength when subjected to heat treatment, and can be sufficiently used as a product. Surprisingly, the product is immersed in water after heat polymerization to increase the strength of the product. It has been found that some compositions can be further increased.

The cementitious composition of the present invention does not particularly require water at the time of kneading, but a small amount of water may be mixed in consideration of the former formability. In addition, at the time of extrusion molding or roll molding, additives such as grocerol and polyethylene glycol can be added to impart plasticity to the kneaded material and improve moldability.

In the cementitious composition of the present invention, a filler may be mixed at the time of kneading. The ratio is determined in consideration of the moldability of the mixture and the strength of the cured product. Fillers include conventional sand, lightweight aggregates, wood flour, heavy calcium carbonate, etc., aluminum hydroxide used as a flame retardant such as plastic and rubber, and inorganic pigments used for coloring purposes. No.

For modifying the cementitious product of the invention, polyamide resins are preferably used as additives.
The polyamide resin used in the present invention is generally alcohol-soluble. These alcohol-soluble polyamide resins include those in which at least a part of the hydrogen of the amide bond -CONH- is substituted with a methoxymethyl group, those having an amide bond -CON (R)-generated from a secondary amine, and the like. is there.

It is considered that a reaction similar to the above-mentioned methylene reaction proceeds in the heating and curing process between the polyamide resin and the phenol resin precursor. This polyamide resin is generally directly added to and dissolved in a phenol resin precursor, but may be used after being dissolved in ethanol or methanol and then added to the phenol resin precursor. The mixing ratio of the polyamide resin is generally preferably 0.5 to 20 parts by weight, more preferably 3 to 12 parts by weight, based on 100 parts by weight of the phenol resin precursor.

In the cementitious product of the present invention, in order to achieve high flexural strength, use of a hydraulic cement in which the particle size distribution is adjusted to multiple modes, or curing of the composition under pressure such as hot pressing For example, the pores can be adjusted. Further, a known silane coupling agent may be added in order to improve the adhesive strength between the filler and / or the hydraulic cement and the phenol resin. As this silane coupling agent, γ-aminopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane and the like can be used.

[0022]

EXAMPLES The present invention will be described below with reference to examples and comparative examples to clarify that the product of the present invention has high strength, excellent water resistance and excellent heat resistance.

Examples 1 to 3 Ordinary Portland cement and alumina cement (Denka Alumina Cement 1 manufactured by Denki Kagaku Kogyo KK)
No.) alone or as a mixture, 100 parts by weight of hydraulic cement, 23 parts by weight of an alcohol-soluble phenol resin precursor (manufactured by Showa Polymer Co., Ltd., trade name: Shaunol) and 2.3 parts by weight of glycerol in a mortar Kneaded in mixer for 6 minutes. This kneaded material is passed through a pair of rolls having the same rotation ratio used for noodle making about 20 times to form a sheet having a thickness of about 1.5 mm and a width of 25 mm and a length of 75 mm.
mm. The 10 compacts cut to the required dimensions were cured by heating at 150 ° C. for 18 hours,
A cementitious product was manufactured.

Of the cured products, five were immediately subjected to a bending test, and the remaining five were immersed in water at 20 ° C. for three days and then subjected to a bending test. The bending test was performed according to JIS R5201, with the distance between supporting points being 50 mm. Table 1 shows the obtained results.

[0025]

[Table 1]

Example 4 100 parts by weight of alumina cement (Denki Kagaku Kogyo Co., Ltd.)
And trade name: Denka Alumina Cement No. 1), 15 parts by weight of an alcohol-soluble phenol resin precursor (manufactured by Showa Polymer Co., Ltd., trade name: Shaunol) and 1.5 parts by weight of glycerol in a tabletop kneader. Kneaded for 6 minutes. This kneaded material is put in a receiving mold, and 150 kgf / cm
^{By applying} a pressure of ² , press molding was performed to dimensions of about 10 mm in thickness, 40 mm in width, and 160 mm in length. After molding, 150
A heat treatment was performed at 18 ° C. for 18 hours to cure, thereby producing a cementitious product. For the five cured products, a bending test was performed according to JIS R5201, with the distance between fulcrums set to 100 mm. The obtained result is the bending strength (kgf
/ Cm ² ): 529.

Example 5 The same material as used in Example 4 was used. 100
Parts by weight of alumina cement, 22 parts by weight of an alcohol-soluble phenol resin precursor and 1.8 parts by weight of glycerol were kneaded for 6 minutes in a tabletop kneader. This kneaded material is
Using a vacuum extrusion machine, thickness 15mm, width 20m
m, 160 mm in length. After molding, the above Example 4
The composition was cured in the same manner as described above, and a bending test was performed. The result obtained is bending strength (kgf / cm2): 551.

Examples 6 to 10 Using an N-methoxymethylated polyamide resin (trade name: Toresin, manufactured by Teikoku Chemical Industry Co., Ltd.) in which about 30% of the amide bond hydrogen was substituted with a methoxymethyl group, and ethanol. A cementitious product was produced by performing the same operation as in Examples 1 to 3, except that the composition of the cementitious composition was changed as shown in Table 2. A bending test was performed in the same manner as in Examples 1 to 3. Table 2 shows the obtained results.

[0029]

[Table 2]

[Examples 11 to 14] In order to ascertain the heat resistance of the cementitious product obtained by the same operation as in Examples 6 and 9, 1% at 200 ° C.
Heat for 8 hours or 6 hours at 300 ° C. From this, a bending test was performed in the same manner as in Examples 1 to 3, and a comparison was made with the bending strength before heating. Table 3 shows the obtained results.

[0031]

[Table 3]

[Comparative Examples 1 and 2] Nine commercial products of Company A having a high bending strength and a thickness of about 4 mm were cut into a width of 25 mm and a length of 75 mm, and three of them were subjected to a bending test. The remaining products were measured at 200 ° C. for 18 hours and 300 hours each to determine the heat resistance.
After heating at 6 ° C. for 6 hours, a bending test was performed and compared with the bending strength before heating. In the bending test, the distance between the fulcrums was set to 50.
mm in accordance with JIS R5201. Table 4 shows the obtained results.

[0033]

[Table 4]

[0034]

According to the present invention having the above-mentioned structure, it is possible to obtain a cementitious composition and a cementitious product exhibiting high strength and extremely excellent water resistance and heat resistance. There is.

Claims (6)

(57) [Claims] 1. A cementitious composition comprising at least one hydraulic cement and an alcohol-soluble phenolic resin precursor substantially free of water but producing water by polymerization. 2. It comprises at least one hydraulic cement, an alcohol-soluble phenolic resin precursor substantially free of water but producing water by polymerization, and additives and / or fillers. Cementitious composition. 3. The cementitious composition according to claim 2, wherein the additive is a polyamide resin. 4. The cementitious composition according to claim 3, wherein the polyamide resin is an aliphatic alcohol-soluble polyamide resin. 5. A cementitious composition containing at least one type of hydraulic cement and an alcohol-soluble phenolic resin precursor containing substantially no water but producing water by polymerization is kneaded, molded and heat-treated. A cementitious product characterized by being hardened by hardening. 6. A cementitious composition comprising at least one hydraulic cement, a substantially water-free alcohol-soluble phenolic resin precursor which produces water by polymerization, and additives and / or fillers. After kneading and molding,
A cementitious product obtained by curing by heating.