JPS6140862A - Mortar composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mortar composition, and more particularly to a mortar composition comprising a polymer dispersion with excellent elasticity and a lightweight foamed aggregate with excellent heat insulation properties.

Conventionally, a mortar composition comprising Portland cement mixed with a polymer dispersion and a lightweight foamed aggregate is known as a lightweight insulating polymer cement mortar. This mortar composition is lightweight, has excellent water resistance, and heat insulation properties.
1 Usually, it is used as mortar to decorate the surface of flooring materials, such as interior or exterior walls of buildings, trains, ships, etc. Therefore, as a protective material for concrete plates, metal lath, metal plates, or asphalt used for rooftop waterproofing as a base material for mortar, it is applied to the surface using a metal trowel, spray, etc., but the mortar tends to crack after hardening. There are drawbacks.

This is caused by shrinkage of the mortar itself, when the board itself bends, thermal expansion and contraction of the board, freezing damage due to the water absorption of the aggregate, etc. This occurs because the mortar has no elasticity and has high water absorption. There are possible cases.

In view of the above-mentioned circumstances, the inventors of the present invention have improved the elasticity of mortar while maintaining the characteristics of conventional lightweight heat-insulating polymer cement.
As a result of various studies on how to prevent the occurrence of cracks in mortar by improving its water absorption, when using a mortar composition in which certain components are blended in a specific proportion, it is possible to prevent the occurrence of cracks due to shrinkage of the mortar itself. Furthermore, the inventors have found that it is possible to significantly suppress the occurrence of cracks caused by the deflection of the base material itself, and the occurrence of freeze-damaged cracks caused by the water absorption of the aggregate, leading to the completion of the present invention.

That is, the gist of the present invention is: ■Portland cement;
(2) Alumina cement 1.5 to 7 times the weight of Portland cement, gypsum 0.3 to 3 times the weight of Portland cement, and polymer components relative to the sum of alumina cement and gypsum. 0.15 to 1.5 times the weight of polymer dispersion and lightweight foamed aggregate as aggregate.Portland cement: 0.02 to 1.5 times the weight of the sum of alumina cement and gypsum.
A mortar composition characterized by containing 0.5 times the weight of lightweight foamed aggregate.

The present invention will be explained in detail below.

In the present invention, it is essential that the mortar composition contains five components: portland cement, alumina cement gypsum, polymer dispersion, and lightweight foamed aggregate.

As for portland cement and alumina cement,
Common commercially available products may be mentioned, and the content of alumina cement is 1.5 to 7 times by weight, preferably 2.3 to 4 times by weight, relative to Portland cement, and when the content of alumina cement is less than the above range. If the amount exceeds the above range, it will not be possible to obtain a mortar with good elasticity and cracks will easily occur. So I don't like it. One of the features of the present invention is that Portland cement and alumina cement are used in combination in a specific ratio.

Furthermore, in the present invention, gypsum is present in addition to the above-mentioned cements. Both gypsum hemihydrate and gypsum trihydrate can be used in the present invention, but gypsum hemihydrate is more effective. Gypsum hemihydrate is not limited to α-type and β-type. The content of gypsum is 0.3 to 3 times by weight, preferably 0.8 to 1.5 times by weight relative to Portland cement. Due to the presence of this gypsum, it is possible to obtain a good mortar layer that is even more excellent in elasticity, has high strength, and is less likely to generate clutter.

Next, the polymer dispersion used in the present invention is not particularly limited as long as it is aqueous, and various conventionally known ones can be used, but usually polyacrylic acid ester 1 polyvinyl acetate, polychloride Vinylidene-polyvinyl chloride.

Thermoplastic resin emulsions such as polyvinylpropionate, polyethylene-polyvinyl acetate, and polypropylene;
Thermosetting resin emulsions such as epoxy resin; Bituminous emulsions such as asphalt rubber and asphalt paraffin; Synthetic rubber latex, etc. such as chloroprene rubber, styrene-butadiene rubber, acrylonitrile-butadiene rubber, methyl methacrylate-butadiene rubber, butadiene rubber, and mixtures thereof. It will be done.

The content of these polymer dispersions is 0.15 to 1.5 times the weight of the polymer component, preferably 0.23 to 1.1 times the weight of the sum of Portland cement, alumina cement, and gypsum. If this content is less than the above range, the water resistance of the mortar will be poor and the elasticity will be significantly lower; if it is more than the above range, on the other hand, the mortar will have improved elasticity but poor strength and durability. It is not desirable because it has the disadvantage that it worsens.

Also, the type of aggregate is vermicierite.

Lightweight foamed aggregates such as vanillite, silica balloons, urethane foam powder 1 Styrofoam powder and granules are used, and the particle size is 0.1 mm to 3.0 mm and the bulk specific gravity is 0.02.
It is preferred to use a lightweight foamed aggregate of ~0.16, most preferably obsidian pearlite granulated expanded polystyrene.

The content of aggregate is usually 0.02 to 0.5 times the weight of the sum of Portland cement, alumina cement, and gypsum, preferably 0.02 to 0.13 times the weight. If this content is less than the above range, the insulation properties of the mortar will be poor and cracks will occur easily, while if it is more than the above range, the insulation properties of the mortar will improve, but the strength and elasticity will be significantly reduced. This is not preferable because it has the drawback of becoming worse and having increased water absorption.

In the present invention, in addition to the above-mentioned components, for example, a pigment 2 dispersant may be used as long as the physical properties of the present invention are not lost.

Fillers and the like may be added as appropriate.

In order to actually form a mortar layer using each of the above-mentioned components, usually, a mixture of each component is thoroughly kneaded with water in an amount of 0 to 0.1 times the weight of the mixture in accordance with a conventional method, and then this is mixed. This can be carried out by spraying with a mortar spray gun or the like or by using a metal trowel.

As described above, according to the present invention, it is possible to obtain a mortar with excellent heat insulating properties and elasticity, which has significantly less occurrence of cracks due to shrinkage of the mortar or deflection of the base material, has low water absorption, and is resistant to frost damage. In the present invention, one of the reasons for obtaining mortar with such excellent elasticity and non-water absorbing properties is that in the case of the specific composition of the present invention, (3CaO
-A120s・6H20) and (CaSO4'2H20)
Furthermore, this produces ettringite (3Ca
This is because O-Al□03.3 Ca S Oa.32H20) is generated.

In other words, since ettringite is a needle-shaped crystal, the resin component enters into the gaps between the needle-shaped crystals, resulting in a structure with excellent elasticity that makes it difficult for cranks to enter.Furthermore, the resin component that enters into the gaps reduces water absorption. . Further, since ettringite has a large amount of crystal water, it is preferable as a mortar containing a relatively large amount of organic matter because it has excellent nonflammability and flame retardancy.

Furthermore, since the present invention contains alumina cement, it hardens to the inside in a short period of time, and the initial strength of the mortar is high.Even when a thick coating is applied, the resin content does not segregate because conventional mortar takes a long time to harden. , it is possible to obtain a uniform mortar with no difference in external and internal elasticity. Furthermore, since lightweight foamed aggregate is used as the aggregate, mortar with good heat insulation properties and workability can be obtained.

Therefore, the mortar composition of the present invention is particularly preferable as a mortar for decorating the surfaces of wall materials, floor materials, etc., for example. Further, the substrate to which the mortar composition of the present invention is applied is not particularly limited, but excellent effects are exhibited when it is applied to metal plates such as iron plates, aluminum plates, metal lath, or as a protective mortar for asphalt. Ru.

Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to the following description unless it exceeds the gist thereof.

In addition, the numerical values other than the number in Table 1 indicate "parts by weight."

Examples 1 to 6 and Comparative Examples 1 to 10 100 parts of Portland cement was mixed with the alumina cement shown in Table 1 and gypsum, and then galvanized with the polymer disverge metal trowel shown in Table 1. The coating was applied to a plate so that the thickness after curing was 4 mm or 7 mm, respectively.

The plate-shaped article having the mortar layer obtained in this way was 606
We conducted an elasticity test on the mortar by bending it up to
The results shown in the table were obtained.

Furthermore, the above mixture was subjected to a JIS R1404 water absorption test, and the results shown in Table 4 were obtained.

Next, the above-mentioned mixture was placed in a mold of 80 x 160 x 40 mm, and the thermal conductivity was measured by the hot wire method, and the results shown in Table 4 were obtained.

Table 1 However, "Alumina" in Table 1 refers to "Alumina Cement"
, "polymer" means "polymer dispersion", the type of polymer dispersion is [AcryJ is [polyacrylic acid ester emulsion J], rEVAj is "ethylene-vinyl acetate copolymer emulsion", and the aggregate is "granular foam StJ is "granular". "Styrofoam" is shown.

The amount of polymer dispersion and aggregate used indicates the weight ratio of polymer dispersion and aggregate to the sum of Portland cement, alumina cement, and gypsum.

"Real 1", "Real 2J", --・-1 --- indicating the sample tooth
-・-2 "Real 6" is "Example 1", [Example 2 J,
---.

This is an abbreviation of “Example 6”, and “Ratio 1
", "Ratio 2J, -1---, r ratio 10" indicates "Comparative Example 1", "Comparative Example 2J, -------, r Comparative Example 10".

Table 2 [Results of elasticity test; thickness 4 rr+ m]
Note) Evaluation of elasticity test

Claims (1)

[Scope of Claims] 1 (1) Portland cement, (2) alumina cement in an amount of 1.5 to 7 times the weight of Portland cement, (3) gypsum in an amount of 0.3 to 3 times the weight of Portland cement, and (4) 0 as a polymer component for the sum of Portland cement, alumina cement, and gypsum.
．． 15 to 1.5 times the weight of polymer dispersion and (
5) A mortar composition characterized by containing lightweight foamed aggregate as an aggregate. 2. The mortar composition according to claim 1, wherein the content of aggregate is 0.01 to 0.5 times the weight of the sum of Portland cement, alumina cement, and gypsum. 3 The lightweight aggregate is one or two of inorganic foams such as vermiculite, perlite, and silica balloons, or organic foam powders such as urethane foam and expanded polystyrene.
The mortar composition according to claim 1 or 2, which is a mixture of more than one species. 4. The mortar composition according to claim 1, wherein the polymer dispersion is an aqueous thermoplastic resin emulsion.