JPS5825057B2 - Materials for inorganic hardened bodies - Google Patents

Description

[Detailed description of the invention] The present invention relates to a material for an inorganic cured body.

Conventionally, blast furnace cement and calcium aluminate trisulfate hydrate (3CaO-A1203-3CaS04-nH202) have been used as materials for inorganic hardened bodies.
n takes a value of approximately 31 or 32, hereinafter referred to as T
Calcium aluminate monosulfate hydrate (abbreviated as SH) precursor, calcium aluminate monosulfate hydrate (3CaOA1203・C
It is widely known that aSO4.nH2O,n takes a value of approximately 12 (hereinafter abbreviated as MSH).

Blast furnace cement is a mixture of blast furnace slag and Portland cement, and is divided into Type A, Type B, and Type 0 depending on the mixing ratio of blast furnace slag and Portland cement.

Such blast furnace cement becomes an inorganic hardened body through hydration hardening.

However, this inorganic cured product has the disadvantage that although the deterioration in strength over time is small, the hardening of blast furnace slag is slow, so the initial strength is low and the impact resistance is also low.

Furthermore, MSH, which is a TSH precursor, reacts with gypsum (CaSO4.2H20) in the presence of water, converts into TSH, and hardens.

However, although this inorganic hardened material has a low specific gravity and excellent initial strength and impact resistance, it partially decomposes (carbonates) due to carbon dioxide gas in the air and becomes porous, resulting in its strength decreasing over time. It had the disadvantage of low durability due to physical deterioration.

As a result of repeated research to eliminate these drawbacks, the inventors have developed a TSH precursor composition containing a TSH precursor and a reactive component that reacts and hardens the TSH precursor, blast furnace cement, and Portland cement. , MgO and Mg
It was discovered that a material for an inorganic cured body containing one or both of (OH)2 can be used to produce an inorganic cured body that has high initial strength and impact resistance, and is also highly durable, and this invention was completed. did.

That is, the gist of the present invention is a material for an inorganic hardened body whose main components are blast furnace slag, Portland cement, at least one of MgO and Mg(OH)2, and a TSH precursor composition. .

Next, this invention will be explained in detail.

The inorganic hardened material of the present invention contains blast furnace slag, Portland cement, one or both of MgO and Mg(OH)2, and a TSH precursor composition as main components.

Here, blast furnace slag, Portland cement, and Mg
Containing one or both of O and Mg(OH)2 and the TSH precursor composition as main components includes cases where only these components are contained and no other components are contained. .

Therefore, the inorganic cured material of the present invention does not necessarily need to contain additives such as reinforcing fibers, synthetic resins, and fillers.

These additives are added to the inorganic cured material as necessary.

As the blast furnace slag and Portland cement used in this invention, publicly known ones are used.

In this case, of course, blast furnace cement containing both blast furnace slag and Portland cement may be used as the source of blast furnace slag and Portland cement.

Known MgO and Mg(OH)2 may also be used.

The TSH precursor composition used in the present invention also refers to a TSH precursor composition that reacts with at least one of the reactive components, such as a gypsum component, a lime component, and an alumina component, in the presence of water.
It refers to a composition containing a TSH precursor that becomes SH and at least one of the above-mentioned reaction components.

Such compositions include, for example, C3A (3CaO-
A1203), C, AH6 (3CaO・A7203m
6H20) t C3A3 S (3CaO* 3A7
203+Ca5O4), A#2(804)3 ・nH
Examples include combinations of TSH precursors such as 2O, MSH and at least one reactive component such as gypsum and CaO.

The blending ratio of the TSH precursor in this TSH precursor composition and the reactive component that reacts and cures the TSH precursor is determined by the reaction.
You may choose so that both are all TSH, or TSH
A portion of the precursor may remain.

The mixing ratio of blast furnace slag (5) and Portland cement (B) is (A)/(B)-1/9 to 9/ by weight.
It is preferable to select 1.

In addition, the blending amount of one or both of MgO and Mg(OH)2 is 1% relative to blast furnace slag in terms of Mg.
It is preferable to select the amount to be 5% (by weight, the same applies hereinafter).

Further, the amount of the TSH precursor composition to be blended is such that the TSH precursor composition is added to the TSH (if the TSH precursor remains, it may be included in the TSH).

However, in that case, the molar ratio of (TSH)/(TSH precursor) must be 2/1 or more.

), the weight ratio is TSH/(A)+ to the total amount of blast furnace slag (5) and Portland slag (B).
It is preferable to select so that (B)=5/5 to 1/9.

In order to manufacture an inorganic cured body using the material for an inorganic cured body of the present invention, it is carried out, for example, as follows.

That is, first, water is added to the material for the inorganic cured body in an amount of 60% or more based on the weight of the material and mixed uniformly.

Next, this mixture is shaped by compression molding, extrusion molding, casting, paper making, etc., and is cured and hardened at a temperature of 90° C. or lower.

In this case, curing at a temperature exceeding 90° C. slows down the curing reaction, which is not preferable.

Next, dry this. In this way, an inorganic cured product with high initial strength and impact resistance and high durability is obtained.

In this case, MgO and Mg(OH)2 accelerate the water hardening of blast furnace slag during the production of the inorganic hardened body, and after the production of the inorganic hardened body, they react with carbon dioxide gas in the air to form carbonates. This is thought to fill the pores generated by carbonation of TSH.

In this invention, it is important that the material for the inorganic cured body contains in an uncured state a TSH precursor composition capable of producing a cured body containing TSH as a main component upon curing.

This improves water hardening and cement [and/or] this composition.
Or, since the water-using hardening of blast furnace slag occurs simultaneously, the TSH obtained by water-using hardening of this composition and the hydrated cement and/or the hydrated blast furnace slag are uniformly and firmly intertwined. appears, and the obtained inorganic hardened product has a strength that is even higher than that of the inorganic hardened product of the hydrated cement cement and/or the blast furnace slag hydrated hardened product alone.

On the other hand, when the TSH is blended in advance, such an effect cannot be expected at all.

The attached drawings clearly illustrate this.

In other words, the ○ and - lines indicate ( Blast furnace cement/TS
H) The relationship between the ratio and the bending strength is shown, and the Δ line and the mu line show the same relationship as above when they are mixed in the TSH state, but if you look at the slope of each line, you can see that I understand that very well.

Such characteristics of the inorganic cured material according to the present invention exhibit particularly excellent effects when this material is used for manufacturing exterior building materials and the like.

This is because exterior building materials and the like are required to be lightweight and have high strength.

As described above, according to the inorganic cured material of the present invention,
It is possible to produce an inorganic cured product that has high initial strength, high impact resistance, and is highly durable.

Next, examples will be described together with comparative examples.

Example 1 Each raw material was blended and mixed as shown below to obtain a material slurry for an inorganic cured body.

Blast furnace slag 100 parts (weight basis, same below) Portland cement 30〃 MSH801 part Gypsum 4011 Mg(OH)2 101 / Asbestos fiber 8〃 Pulp fiber 15〃 Water 2500 / 1 Next, the above slurry is made into a plate shape. This shaped body was pressed to obtain a plate-shaped shaped body (green sheet) having a thickness of 10 mm.

Next, this green sheet was cured under moist heat at 80°C for 10 hours, and then left to stand for 5 days.

As a result, a gray plate-shaped inorganic cured body was obtained.

Example 2 The composition of each raw material was changed as follows.

A plate-shaped inorganic cured body was obtained in the same manner as in Example 1 except for the above.

Blast furnace slag 100 parts Portland cement 100〃 MSH80〃 Gypsum 4 Q 11Mg (0H
)2 10 tt asbestos fiber
10〃 Pulp fiber 15〃 Water 2600 parts Example 3 The composition of each raw material was changed as follows.

A plate-shaped inorganic cured body was obtained in the same manner as in Example 1 except for the above.

Blast furnace slag 100 parts Portland cement 100〃 MSH100 // Gypsum 50〃 M g 0 7 tt Glass fiber
5〃Pulp fiber 20〃Water 3000 //Example 4 The composition of each raw material was changed as follows.

A plate-shaped inorganic cured body was obtained in the same manner as in Example 1 except for the above.

Blast furnace cement type 0 200 parts MSH100// Gypsum 40〃 Mg(OH)2 15tt Glass fiber 5〃 Pulp fiber 20〃 Water 30001/ Comparative example 1 Among the raw materials used in Example 1, 1. Mg(OH)2 was removed.

A plate-shaped inorganic cured body was obtained in the same manner as in Example 1 except for the above.

Comparative Example 2 Among the raw materials used in Example 2, MSH and gypsum were excluded.

A plate-shaped inorganic cured body was obtained in the same manner as in Example 2 except for the above.

Comparative Example 3 Among the raw materials used in Example 3, blast furnace slag and portolan cement were excluded.

A plate-shaped inorganic cured body was obtained in the same manner as in Example 3 except for the above.

The bulk specific gravity, bending strength, Charpy impact strength, dimensional change rate, and
Table 1 shows the planar adhesive strength, sawing properties, planing properties, and nailing properties.

As is clear from Table 1, it can be seen that the performance of the plate-shaped inorganic cured bodies obtained in the Examples is extremely excellent.

Furthermore, various durability tests were conducted on the plate-shaped inorganic cured bodies obtained in the above Examples and Comparative Examples.

The results are shown in Table 2.

The various tests shown in Table 2 were conducted as follows.

(1) Hot and cold test After immersing the plate-shaped inorganic cured body in water for 18 hours,
The sample was kept at 80°C for 2 hours, then immersed in water for 2 hours, then taken out and kept at 80°C for 2 hours.

This was considered as one cycle, and 20 cycles were repeated.

(2) Hot water test The plate-shaped inorganic cured body was immersed in hot water at 80°C for 8 hours, and then left indoors for 16 hours.

This was repeated for 1 cycle and 20 cycles.

(3) Flowing water test The plate-shaped inorganic cured body was immersed in running water for 3 months.

(4) Accelerated test using weatherometer It was conducted according to JISA1415 (1500 hours).

(5) Outdoor exposure test It was conducted according to JISAI 410 (1 year exposure).

[Brief explanation of drawings]

The drawings are explanatory diagrams for explaining the invention in detail.

Claims (1)

[Claims] 1. A material for an inorganic hardened body, the main components of which are blast furnace slag, Portland cement, at least one of MgO and Mg(OH)2, and a calcium aluminate trisulfate hydrate precursor composition.