JPH0789756A - Cementitious composition and product therefrom - Google Patents

Abstract

PURPOSE:To obtain the subject composition and its product high in bending strength and excellent in water resistance and resistance by compounding at least one kind from hydraulic cement and an alcohol-soluble phenolic resin precursor which polymerizes which generating water. CONSTITUTION:Alcohol-soluble phenolic resin precursor of 10-60 pts.wt. which does not substantially contain water but generates water by polymerization is added to 100 pts.wt. of at least one kind of hydraulic cement by adjusting viscosity with alcohols. 0.5-20 pts.wt. aliphat. alcohol-soluble polyamide resin as an additive and sand, aluminum hydroxide and an inorg. pigment as a filler are added and compounded to 100 pts.wt. phenolic resin precursor at need. After kneading the compounded matter using a conventional mixing device and forming to a prescribed shape and dimension, the formed body is subjected to a heat treatment at 100-300 deg.C to polymerize the phenolic resin precursor and subject the hydraulic cement to hydration reaction with the water generated by polymerization, and the cementitious product is obtained.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a cementitious composition having high strength and excellent heat resistance and water resistance, and a product thereof.

[0002]

Bending strength of cement products manufactured using hydraulic cement is generally 50 to 100 kgf / c.
It is as low as m ² and has been used for many years as a reinforcing material. In order to improve the bending strength of cement products, short fibers such as glass fibers and carbon fibers have been added for reinforcement, and the bending strength is 400 kgf / cm ^2.
Is rarely exceeded.

Generally, the hardened cement material has higher strength when the amount of water used for kneading is smaller, and the smaller the pores contained in the hardened material, the higher the strength. As an example thereof, a hardened cement product having extremely high bending strength without the need for fibers or high compression molding is known (Japanese Patent Publication No. 59-43431). This hardened cement is
This is because the hydraulic cement, water, and the aqueous organic polymer are kneaded and mixed by a high shearing force such as with a two-roll mill to limit the size and proportion of pores in the hardened cement. However, since these cement hardened bodies having improved flexural strength contain an aqueous organic polymer, there is a problem that the strength is remarkably reduced or the water resistance is poor such as swelling when immersed in water.

Further, there is an example in which an isocyanate compound is reacted with a hydrophilic group to improve water resistance (Japanese Patent Laid-Open No. 63-63160).
-206342), some isocyanate compounds have a strong irritating odor and also have toxicity, so that there is a problem in kneading and molding, or a urethane derivative which is a main reaction product has low heat resistance. There was a problem.

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In view of the above-mentioned conventional techniques and problems, the present invention has high bending strength,
Moreover, it is an object of the present invention to provide a cementitious composition having excellent water resistance and heat resistance and a product thereof.

[0006]

SUMMARY OF THE INVENTION The present invention is a composition comprising at least one hydraulic cement, an alcohol-soluble phenolic resin precursor that polymerizes while producing water, and additives and / or fillers added as necessary. , Kneading, and then cured by heat treatment after molding, a cementitious product satisfying the above characteristics is obtained, and even if the product is immersed in water, there is almost no strength decrease, and on the contrary, a composition showing an increase in strength is also present. After discovering something, it was completed. That is, essentially no water is present in the composition before the curing process in the present invention, but the phenol resin precursor is polymerized and cured by heat treatment of the composition, and water generated as a result of the polymerization TECHNICAL FIELD The present invention relates to an invention of a cementitious composition which exhibits high strength and extremely excellent water resistance and heat resistance, and a product thereof, in which a hydration reaction of cement occurs.

As the hydraulic cement used in the present invention, a conventional cement can be used. Examples thereof include Portland cement (eg, normal Portland cement, early strength Portland cement, moderate heat 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 can be used alone, but the above cement is used in 2
It is also possible to use a mixture of two or more species.

The alcohol-soluble phenolic resin precursor, which is polymerized while producing water, has the following moldability.
Use it after adjusting the viscosity to the required viscosity with alcohol.
An alcohol solution having a nonvolatile content of 40 to 70% is preferably used. As the alcohol in the present invention, a wide range of alcohols such as methanol, ethanol, propanol, butanol, cyclohexanol, phenol, cresol, ethylene glycol and trimethylene glycol can be used.

The mixing ratio of the phenolic resin precursor is 100 parts by weight of the hydraulic cement (when the filler is mixed, 100 parts by weight of the granular material component obtained by adding the filler to the hydraulic cement). 10 to 60 parts by weight, preferably 12 to 30 parts by weight. When the amount of the phenol resin precursor is 8 parts by weight or less, the kneading with the hydraulic cement cannot be performed well and the strength of the hardened product is low. On the other hand, if the amount exceeds 60 parts by weight, the cured product may crack and the strength may reach the limit, which is not economically preferable.

Kneading of the hydraulic cement, the phenolic resin precursor, and additives and / or fillers added as necessary can be carried out by using a conventional mixing device such as an Eirich mixer or a spiral mixer. . When the blending ratio of the phenolic resin precursor is relatively small, a mixing device capable of exerting a compression action, a shearing action, and a spatula action is preferable. 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-molded, extrusion-molded, press-molded, or cast into a mold to have a desired size and shape, and then heat-treated to polymerize the phenol resin precursor. Heating is generally in the range of 100 to 300 ° C, preferably 150 to 250 ° C. The phenol resin precursor is polymerized by this heating, and the hydraulic cement is hydrated by the water generated by the polymerization,
Provides high strength.

Generally, a phenol resin undergoes a rapid curing reaction in an acidic region of pH 7 or lower, but even in an alkaline region of pH 7 or higher, if it is heated at a temperature of 150 to 250 ° C. for a relatively long time. It can be fully cured. It is known that this curing reaction mainly proceeds by the following model condensation reaction. [Here, R represents a phenol nucleus] Furthermore, the water produced by the methyleneation reaction rapidly hydrates the hydraulic cement under heating to form a cement hydrate. Regarding the development mechanism of high bending strength, through the process as described above, the strong three-dimensional crosslinked structure of the phenol resin and the cement hydrate cross each other to form the structure of the cement product, and high strength is achieved. Interpreted as possible.

The cementitious composition of the present invention exhibits a high bending strength when heat-treated and can be sufficiently used as a product. Surprisingly, the strength of the product can be improved by dipping it in water after heat-polymerization. It has been found that some compositions can be further increased.

The cementitious composition of the present invention does not require water during kneading, but a small amount of water may be admixed in consideration of moldability in advance. Further, at the time of extrusion molding or roll molding, an additive such as glycerol or polyethylene glycol may be added in order to impart plasticity to the kneaded product and improve moldability.

The cementitious composition of the present invention may be mixed with a filler if necessary at the time of kneading. The ratio is determined in consideration of the moldability of the mixture and the strength of the cured product. Filling materials include conventional sand, lightweight aggregate, wood powder, heavy calcium carbonate, aluminum hydroxide used as a flame retardant for plastics and rubber, inorganic pigments used for coloring, etc. Can be mentioned.

To modify the cement product of the present invention,
Polyamide resin is preferably used as an additive. The polyamide resin used in the present invention is generally soluble in alcohol. These alcohol-soluble polyamide resins include
Examples thereof include those in which at least a part of hydrogen of the amide bond —CONH— is substituted with a methoxymethyl group, and those having an amide bond —CON (R) — generated from a secondary amine. It is considered that a reaction similar to the above-described methyleneation reaction proceeds between the polyamide resin and the phenol resin precursor in the heat curing process. This polyamide resin is generally used by directly adding it to the phenol resin precursor and dissolving it, but it can also be used by adding it to the phenol resin precursor after dissolving it in ethanol or methanol. Generally, the mixing ratio of the polyamide resin is preferably 0.5 to 20 parts by weight, more preferably 3 to 12 parts by weight with respect to 100 parts by weight of the phenol resin precursor.

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

[0017]

EXAMPLES Examples and comparative examples of the present invention will be described below to clarify that the products of the present invention have high strength, water resistance and heat resistance.

Examples 1 to 3 Ordinary Portland cement and alumina cement (Denka Alumina Cement No. 1 manufactured by Denki Kagaku Kogyo Co., Ltd.)
100 parts by weight of hydraulic cement, alone or mixed with
23 parts by weight of an alcohol-soluble phenolic resin precursor (manufactured by Showa Highpolymer Co., Ltd., trade name Shonor) and 2.3 parts by weight of glycerol were kneaded in a mortar mixer for 6 minutes. The kneaded product was passed between a pair of rolls having the same rotation ratio used for noodle making about 20 times to have a thickness of about 1.5.
The sheet was formed into a sheet having a size of 25 mm and cut into a width of 25 mm and a length of 75 mm. Cementitious products were produced by heat-treating 10 molded bodies cut into the required size at 150 ° C. for 18 hours to cure them.

Of the cured products, 5 pieces were immediately subjected to a bending test, and the remaining 5 pieces were immersed in water at 20 ° C. for 3 days and then subjected to a bending test. In the bending test, the distance between fulcrums should be 5
The distance was set to 0 mm, and the measurement was performed according to JIS R5201.
The results obtained are shown in Table 1.

[Table 1]

Example 4 100 parts by weight of alumina cement (Denki Kagaku Kogyo KK)
Manufactured by Denka Alumina Cement No. 1), 15 parts by weight of an alcohol-soluble phenolic resin precursor (Showa Polymer Co., Ltd., trade name Shonor) and 1.5 parts by weight of glycerol for 6 minutes with a tabletop kneader. Kneaded This kneaded product is put into a receiving mold and 150 kgf / cm in a pressing mold.
A pressure of ² was applied, and press molding was performed to dimensions of a thickness of about 10 mm, a width of 40 mm and a length of 160 mm. 150 ° C after molding
And heat-treated for 18 hours to cure the cement-based product. With respect to the five cured products, a bending test was performed according to JIS R5201 with the distance between fulcrums set to 100 mm. The results obtained are shown below. Bending strength (kgf / cm ² ): 529

Example 5 The same material as in Example 4 was used. 100 parts by weight of alumina cement, 22 parts by weight of alcohol-soluble phenolic resin precursor and 1.8 parts by weight of glycerol were kneaded for 6 minutes in a tabletop kneader. This kneaded product was molded into a thickness of 15 mm, a width of 20 mm, and a length of 160 mm using a vacuum extrusion molding machine. After molding, it was cured in the same manner as in Example 4 and a bending test was performed. The results obtained are shown below. Bending strength (kgf / cm ² ): 551

Examples 6 to 10 A cement was prepared by using N-methoxymethylated polyamide resin (trade name: resin resin manufactured by Teikoku Kagaku Sangyo Co., Ltd.) in which hydrogen of amide bond was replaced by about 30% by methoxymethyl group and ethanol. A cementitious product was produced in the same manner as in Examples 1 to 3 except that the formulation of the quality composition was changed as shown in Table 2. From this, a bending test was performed in the same manner as in Examples 1 to 3. The obtained results are shown in Table 2.

[Table 2]

Examples 11 to 14 In order to grasp the heat resistance of the cementitious products obtained by the same operations as in Examples 6 and 9, heating was further performed at 200 ° C. for 18 hours or 300 ° C. for 6 hours. From now on, Example 1
Bending tests were performed in the same manner as in ~ 3 and compared with the bending strength before heating. The results obtained are shown in Table 3.

[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. In order to grasp the heat resistance, each of the three remaining products was heated at 200 ° C for 18 hours and 30 times.
After heating at 0 ° C. for 6 hours, a bending test was performed to compare with the bending strength before heating. In the bending test, the distance between fulcrums should be 5
The distance was set to 0 mm, and the measurement was performed according to JIS R5201.
The results obtained are shown in Table 4.

[Table 4]

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Claims (4)

[Claims] 1. Containing at least one hydraulic cement, an alcohol-soluble phenolic resin precursor which is substantially free of water but produces water by polymerization, and optionally additives and / or fillers. A cementitious composition comprising: 2. The cementitious composition according to claim 1, wherein the additive is a polyamide resin. 3. The cementitious composition according to claim 1, wherein the polyamide resin is an aliphatic alcohol-soluble polyamide resin. 4. A cement containing at least one hydraulic cement, an alcohol-soluble phenolic resin precursor which is substantially free of water but produces water by polymerization, and optionally an additive and / or a filler. A cementitious product obtained by kneading and molding a high-quality composition, followed by heat treatment and curing.