JPH0769754A - Light-weight cellular concrete building material - Google Patents

Abstract

PURPOSE:To improve the surface properties by using a foaming agent containing an alkyl sulfate-based compound represented by a specified formula and forming air bubble cells having a prescribed average diameter. CONSTITUTION:With an alkyl sulfate-based compound represented by the formula [R is a 8 to 20C aliphatic hydrocarbon; A is H or methyl; (n) is 0 or 1 to 5; X is an alkaline metal, ammonium or an amine cation], e.g. oxyethylene lauryl sulfate ammonium, a respectively suitable amount of a foaming agent such as lauryl alcohol, a solvent such as Methey Cellosolve and water are blended to prepare a foaming agent. An air bubble generator is then packed with glass beads having a prescribed particle size and the prepared foaming agent is allowed to flow together with compressed air therethrough to form a foamed solution containing air bubbles. A prescribed amount of the foamed solution is then uniformly admixed with a cement slurry to prepare an air bubble-containing slurry. The obtained air bubble-containing slurry is cast into a molding frame, hardened and subsequently cured, thus producing the objective light-weight cellular concrete panel containing air bubble cells of 200 to 400mum average diameter.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a lightweight cellular concrete building material.

[0002]

[Background Art] Cement and silica sand as main raw materials, concrete slurry mixed with air bubbles is placed in a molding frame in which a reinforcing material is arranged, and temporarily cured, and then a molded panel A lightweight cellular concrete panel produced by steam curing in a high temperature, high pressure autoclave has been put into practical use. In the manufacturing process of a lightweight cellular concrete panel, the cells are produced by using, for example, a foaming agent, and the produced cells are mixed in a concrete slurry. There are several types of such foaming agents, but protein-based ones are relatively often used because of their excellent foaming characteristics.

When the protein-based foaming agent is used,
A fine uneven pattern was generated on the surface of the panel, and the surface quality as the outer wall was poor. It is considered that this is because the protein-based foaming agent is not good in terms of oil resistance, and at the time of demolding, the oil-based mold releasing agent breaks the pores of the outer wall surface to increase the diameter of the pores. Further, since such a foaming agent has a protein origin, the panel may have an odor.

Therefore, as a desirable foaming agent, one capable of solving these problems is required, and in addition to these requirements, in terms of factory production, it is excellent in bubble stability and can be roller-finished after molding. Is required. When a foaming agent that does not have the above-mentioned problems in terms of surface properties and odors was searched for, it was found that an alkylsulfate-based foaming agent was almost applicable.

[0005]

When the above alkyl sulphate type foaming agent is used, the panel obtained under the usual manufacturing conditions of concrete building materials has physical properties which are higher than those of the case where a protein type foaming agent is used. There was a problem that (especially compressive strength) was lowered. Therefore, it is an object of the present invention to provide a lightweight cellular concrete building material that can prevent deterioration of physical properties when an alkyl sulfate-based foaming agent is used and that has good surface properties.

[0006]

The lightweight cellular concrete building material according to the present invention has pores formed by using a foaming agent containing an alkyl sulfate compound represented by the following general formula. The average diameter of the bubble holes is 200.
It is characterized in that it is from μm to 400 μm.

[0007]

[Chemical 2]

In the formula, R is an aliphatic hydrocarbon group having 8 to 20 carbon atoms, A is hydrogen or a methyl group, m is 0 or an integer of 1 to 5,
X is an alkali metal, ammonium or amine cation. The aliphatic hydrocarbon group having 8 to 20 carbon atoms of R is
It is a saturated or unsaturated alkyl group having a straight or branched chain. Examples of such an alkyl group include an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group,
Tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, eicodecyl group, oleyl group, linoleyl group,
There are linolenyl groups and the like.

Of these, alkyl groups having 10 to 16 carbon atoms are preferable, and dodecyl group and tetradodecyl group are particularly preferable. When the number of carbon atoms is out of the above range, the bubble force is lowered and a building material having a desired specific gravity cannot be obtained. m
Represents the number of moles of ethylene oxide or propylene oxide added, and is usually 0 or an integer of 1 to 5, and preferably 1 to 3. When the number of added moles is 5 or more, the foaming power decreases, which is not practical.

X represents a counter ion of an alkyl sulfate ester, for example, alkali metal (Li, Na, K, etc.), ammonium, amine cation [alkyl (C 1-18) amine (methylamine, propylamine, hexylamine, Nonylamine, dodecylamine, pentylamine, stearylamine, etc.), alkanolamines (monoethanolamine, diethanolamine, triethanolamine,
Amine cations such as propanolamine, isopropanolamine, cyclohexylethanolamine, etc.), and mixtures of two or more thereof. Preferred are Na, ammonium and alkanolamine cations, and particularly preferred are Na and ethanolamine cations.

Specific examples of such an alkyl sulfate include oxyethylene (1) lauryl sulfate.
Na, polyoxyethylene (2) tetradecyl sulphate Na, oxyethylene (1) lauryl sulphate ammonium, dodecyl sulphate ammonium, polyoxyethylene (2) tetradecyl sulphate ammonium, oxyethylene (1) lauryl sulphate triethanolamine salt, dodecyl Examples include sulfate ethanolamine salt and polyoxyethylene (2) tetradecyl sulfate triethanolamine salt. The number in parentheses next to oxyethylene or polyoxyethylene represents the average number of moles of ethylene oxide added.

In addition to the alkyl ether sulfate, the foaming agent according to the present invention contains a foam stabilizer for stabilizing the foam, a solvent for dissolving the foam stabilizer in the alkyl ether sulfate, and the like. You can As the foam stabilizer, lauryl alcohol, myristyl alcohol,
Higher alcohols such as cetyl alcohol can be used. Examples of the solvent include cellosolve-based solvents (methyl cellosolve, ethyl cellosolve, n-propyl cellosolve, etc.),
Carbitol (ethyl carbitol, butyl carbitol, etc.) can be used.

In the present invention, the foaming agent containing the alkylsulfate compound is used to foam, and the average diameter of the pores in the building material formed by the bubbles is set to 200 μm to 400 μm. . When the average diameter of the pores is less than 200 μm, the strength of the building material decreases. On the other hand, if the average diameter of the pores exceeds 400 μm, the surface properties of the building material deteriorate, which is not preferable.

Any method may be used to make the average diameter of the pores in the building material 200 to 400 μm. For example, in the case of a method (preform method) in which bubbles are generated through a foaming agent through a cylindrical bubble generator in which beads are stored together with air, and the resulting bubble liquid is mixed into a building material slurry, an appropriate diameter is used. It is possible to select the beads to be carried out. A method of foaming in the slurry while producing it (mix foam method) may be used, but the preform method is preferable because it is difficult to control the diameter of bubbles.

[0015]

EXAMPLE An example of applying the present invention to an autoclave curing lightweight cellular concrete panel as a building material will be described. First, glass beads having an appropriate diameter are filled in a tubular bubble generator, and the alkylsulfate-based foaming agent aqueous solution according to the present embodiment is allowed to flow along with compressed air into the beads from above to generate bubbles from the bottom of the device. To obtain a bubbly liquid containing.

The size of the bubbles in the bubble liquid generated by the beads and the size of the pores in the produced panel vary depending on not only the diameter of the beads used but also the type of the foaming agent and the cement slurry. . Therefore, as in the following experimental example, data of the pore diameter in the panel obtained by a specific bead diameter, foaming agent and type of cement slurry is reserved, and based on this, it is used according to the type of foaming agent and cement slurry. It is necessary to select the bead diameter to be used.

Next, the foam liquid is mixed into the cement slurry and uniformly mixed to obtain a cement slurry containing bubbles. The following is, as usual, this concrete slurry is placed in the molding frame in which the reinforcing bar is placed, and after temporarily hardening, the molded panel is heated to a high temperature,
A lightweight cellular concrete panel was produced by steam curing in a high pressure autoclave.

Experimental Examples 1 to 6 In each of the above examples, the type and concentration of the alkyl sulfate type foaming agent, the type of cement, the water / cement ratio and the bead diameter used were set as shown in Table 1. A lightweight cellular concrete panel according to the example was obtained. Foaming agent a-
The composition of 1 or a-2 is as follows. a-1: 100 parts by weight of ammonium oxyethylene lauryl sulfate, 17 parts by weight of lauryl alcohol as a foam stabilizer, 100 parts by weight of methyl cellosolve as a solvent and 120 parts of water
A foaming agent in which parts by weight are mixed. a-2: A foaming agent in which 100 parts by weight of sodium oxyethylene lauryl sulfate, 17 parts by weight of lauryl alcohol, 100 parts by weight of methyl cellosolve and 120 parts by weight of water are mixed.

Table 1 also shows the results of evaluating the properties of the surface of the building material by measuring the pore diameter of each lightweight cellular concrete panel and the compressive strength of the panel. In the evaluation of the property of the surface of the building material, ◯ is good, Δ is normal, and x is bad. In the column of comprehensive evaluation, ⊚ indicates good strength and surface properties, ◯ indicates normal strength and surface properties, and x indicates at least one of strength and surface properties is poor.

Comparative Examples 1 to 5 Light-weight cellular concrete panels according to Comparative Examples were obtained in the same manner as in the above Experimental Examples. However, the foaming agent a-3 is a protein foaming agent [Formix CII (trade name), manufactured by Misawa Ceramic Chemical Co., Ltd.]. Then, with respect to the lightweight cellular concrete panels of each comparative example, the cell pore diameter and the compressive strength of the panel were measured in the same manner as in the above experimental example, and the results of evaluating the properties of the building material surface are shown in Table 1.

[0021]

[Table 1]

From Table 1, the lightweight cellular concrete panels according to Experimental Examples 1 to 6 have cellular pores formed by using a foaming agent containing an alkyl sulfate compound, and the average pore diameter is 200 μm. Since it is up to 400 μm, it has the same compressive strength as the case of using the conventional protein-based foaming agent, and the property of the building material surface is also good.

On the other hand, the lightweight cellular concrete panel according to Comparative Example 1 is a protein-based foaming agent, and therefore the properties of the building material surface are poor even if the average pore diameter is 200 μm to 400 μm. The lightweight cellular concrete panels according to Comparative Examples 2 to 5 have cellular pores formed by using a foaming agent containing an alkyl sulfate compound, but the average diameter of the cellular pores is outside the range according to the present invention. Therefore, there is a problem in the compressive strength of the panel or the property of the surface of the building material.

[0024]

EFFECTS OF THE INVENTION According to the lightweight cellular concrete building material of the present invention, it is possible to prevent deterioration of physical properties when an alkylsulfate-based foaming agent is used, and the building material has good surface properties.

Claims (1)

[Claims] 1. A cell having pores formed by using a foaming agent containing an alkyl sulfate compound represented by the general formula of the following chemical formula 1, wherein the average diameter of the pores is 200 μm to 400 μm.
A lightweight cellular concrete building material. [Chemical 1] (In the formula, R is an aliphatic hydrocarbon group having 8 to 20 carbon atoms, A is hydrogen or a methyl group, m is 0 or an integer of 1 to 5, and X is an alkali metal, ammonium or amine cation.)