JP6078936B1 - Foaming agent for foam mortar - Google Patents

Abstract

An object of the present invention is to provide a foaming agent for foam mortar that exhibits excellent foam stability. SOLUTION: A cationized guar gum as a foam stabilizer is added to a composition comprising a foaming component composed of one or both of polyoxyethylene alkyl ether sulfate and / or alkyl sulfate ester salt and fatty acid alcohol as an essential component. It was discovered that the bubbles obtained from the foaming agent added in an amount of 1 to 5% are extremely stable and useful for the production of bubble mortar, and a means for solving this problem has been obtained.

Description

Detailed description of the invention

The present invention relates to a foaming agent for cellular mortar.

Conventionally, it has been known that protein-based foams and surfactants are used as foaming components for foam mortar as foaming components, and water-soluble polymers such as aliphatic alcohols, various cellulose derivatives and polyvinyl alcohol are used in combination as foam stabilizers. It has been.

Japanese Examined Patent Publication No. 6-45511

Problems to be solved by the invention

The conventional foaming agent does not necessarily have a sufficient bubble stability, and there are problems that many bubbles disappear during pumping and the specific gravity of the bubble mortar may not reach a desired value. That is, an object of the present invention is to provide a foam mortar foaming agent that exhibits excellent cell stability.

It is a composition (A + B) in which an aliphatic alcohol (B) having 8 to 20 carbon atoms is used in combination with a foaming component (A) composed of one or both of polyoxyethylene alkyl ether sulfate and / or alkyl sulfate ester salt, Foaming agent for cellular mortar (A + B + C) characterized in that 0.1 to 5% by weight of cationized guar gum (C) is added based on the total weight of (A + B) with a content ratio of 80/20 to 90/10 ).

Features of the bubble mortar foaming agent of the present invention have the general formula _{(R-O - (- CH} 2 CH 2 O-) n-SO 3 M) ( wherein, R represents an aliphatic of 8-20 carbons carbonized A foaming component (A) by polyoxyethylene alkyl ether sulfate and / or alkyl ether sulfate represented by a hydrogen group, n is an integer of 0 to 10, and M is an alkali metal cation, ammonium or amine cation. And consisting of an aliphatic alcohol (B) having 8 to 20 carbon atoms and a cationized guar gum (C).

Compared to the case where only various cellulose derivatives, polyvinyl alcohol and fatty acid alcohol are used, the present invention has very high foam stability, and the foam mortar made using this does not impair the volume even when pumped.

Cationized guar gum (C) is essential, and addition of 0.1 to 5% is desirable. If the amount is more than that, agglomeration effect appears and affects the production of bubble mortar, which is not practical.

Guar gum is a water-soluble natural polymer polysaccharide. It is composed of a mannose main chain and a galactose side chain, and its composition ratio is 2: 1. It is also called galactomannan or guaran as a general name.

The aliphatic alcohol (B) is used for stabilizing foam, and is a straight or branched natural or synthetic saturated or unsaturated primary or secondary monohydric alcohol having 8 to 20 carbon atoms, such as octyl alcohol. Decyl alcohol, lauryl alcohol (dodecyl alcohol), myristyl alcohol, cetyl alcohol, stearyl alcohol, eicosyl alcohol, synthetic alcohol, and mixtures of two or more thereof. Of these, preferred are lauryl alcohol and myristyl alcohol.

The foaming component (A) is one of a polyoxyethylene alkyl ether sulfate and / or an alkyl sulfate ester salt represented by the general formula (R—O — (— CH ₂ CH ₂ O—) n—SO ₃ M) Both foaming components can be used.

In the general formula (R—O — (— CH ₂ CH ₂ O—) n —SO ₃ M), the aliphatic hydrocarbon group having 8 to 50 carbon atoms represented by R is a saturated or unsaturated linear or branched group. It is an alkyl group. For example, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, eicosyl group, oleyl group, linoleyl group, linolenyl group, etc. Is mentioned. Among these, an alkyl group having 8 to 20 carbon atoms is preferable from the viewpoint of foaming power, and a dodecyl group is particularly preferable.

  If necessary, the foaming agent for cellular concrete of the present invention may contain a water-soluble organic solvent. The water-soluble organic solvent can be used without limitation as long as it is an organic solvent that does not inhibit foaming properties and is easily dissolved in water. For example, cellosolve solvents (methyl cellosolve, ethyl cellosolve, n-propyl cellosolve, n-butyl cellosolve) , Isobutyl cellosolve and phenyl cellosolve, etc.), carbitol solvents (ethyl carbitol, butyl carbitol, etc.), polyoxyethylene lower alkyl monoether (polyoxyethylene (3 mol) monomethyl ether) having 3 to 10 addition moles of ethylene oxide Etc.) Diols having a molecular weight of 500 or less (ethylene glycol, diethylene glycol, polyethylene glycol, etc.) and mixtures of two or more thereof. Of these, cellosolve solvents and polyoxyethylene lower alkyl ethers are preferred, with butyl cellosolve and isobutyl cellosolve being more preferred.

Examples of amphoteric surfactants are those that do not inhibit foaming properties, and examples include alanine type, imidazolinium betaine type, aminopropyl betaine type, and aminodipropion type. The imidazolinium betaine type is preferable. The amount of amphoteric surfactant added is preferably 99: 1 to 70:30 with respect to the foaming component (A) and the aliphatic alcohol (B).

The foaming agent of the present invention can be used in either pre-forming or mixed forming when producing a foam mortar.

The preform method is widely used because of advantages such as easy control of the amount of bubbles in the mortar and a small amount of foaming solution to be used, compared to the mixed foam method.

In order to generate bubbles from the foaming liquid diluted with the foaming agent, there are methods of stirring the foaming liquid vigorously and blowing air into the foaming liquid. The method of sending the foam together with the foaming liquid and the compressed air to make it foamed efficiently is simple.

Subsequently, the obtained air bubbles can be mixed and dispersed in cement milk or mortar with a mixer or the like to produce lightweight aerated concrete.

Examples of cement include ordinary Portland cement, early-strength Portland cement, fly ash cement, and blast furnace cement, and are not affected by the type of cement.

Examples of water include tap water, groundwater, seawater and the like. There are no particular restrictions on the type of aggregate, and sand, silica sand, lightweight aggregate, and clay used in normal mortars are listed.

The construction method of the mortar containing the product of the present invention may be the same as in the conventional case, and various methods such as filling into a mold and pouring with a caulking gun can be taken. In addition, the curing method may be any method of air-drying curing, wet air curing, heating accelerated curing (steam curing, autoclave curing, etc.), and each curing method may be used in combination.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.

[Comparative Examples 1 to 8] [Examples 1 and 2]
Using the foaming component (A) and the aliphatic alcohol (B) shown in Table 1, a foaming agent to which (C) the cationized guar gum and the comparative water-soluble polymer were added was prepared.
(A) :( B) :( C) = 83: 14: 3 (pure weight ratio)

[Bubble stability test]
The foaming agent shown in Table 2 is diluted 20 times and sent into a cylindrical foaming machine filled with nylon mesh together with compressed air to generate fine bubbles, which are then filled into a container with a height of 60 cm and a volume of 90 l. Then, it was allowed to stand in an open state at room temperature and the bubble stability was compared. The results are shown in Table 3.

About the result represented in Table 3, it turns out that bubble stability is improving significantly compared with the conventional polyvinyl alcohol and a cellulose derivative.

Poor blended air milk of the composition shown in Table 4 using a foaming agent [Comparative Example 2] prepared with a cellulose derivative that is a conventional water-soluble polymer and a foaming agent [Example 1] prepared using cationized guar gum. Was produced by a preform method using the bubbles generated by the above-described method using a 20-fold dilution of the foaming agent.

The prepared air milk (slurry) was allowed to stand and the change in specific gravity over time was measured. The results are shown in Table 5. As is clear from the results, the foaming agent using the cellulose derivative is defoamed and the specific gravity value is increased, whereas the foaming agent of the present invention shows almost no change in the specific gravity value. Further, in the slurry of Example 1, fine bubbles were uniformly dispersed, whereas in the slurry using the foaming agent of Comparative Example 2, shrinkage due to defoaming and a large number of coarse bubbles were observed.

As described above, it was confirmed that the foaming agent of the present invention improves the bubble stability without impairing the foaming performance at all. The foam mortar produced using the present invention has a high volume retention and is useful for filling cavities for civil engineering.

Claims (1)

It is a composition (A + B) in which an aliphatic alcohol (B) having 8 to 20 carbon atoms is used in combination with a foaming component (A) composed of one or both of polyoxyethylene alkyl ether sulfate and / or alkyl sulfate ester salt, Foaming agent for cellular mortar (A + B + C) characterized in that 0.1 to 5% by weight of cationized guar gum (C) is added based on the total weight of (A + B) with a content ratio of 80/20 to 90/10 ).