JPH0343220B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an emulsion-containing cement composition that is easy to work with with a trowel and has a water-reducing effect, and at the same time, it also relates to a composition that, upon curing, provides concrete with extremely good chemical resistance. Conventionally, cement compositions containing emulsions have been proposed in order to obtain concrete with excellent breathing resistance, distortion resistance, impact resistance, adhesion, etc. A vinyl acetate copolymer resin emulsion or an acrylic acid ester copolymer resin emulsion copolymerized in the presence of a type surfactant, and a vinyl acetate copolymer resin emulsion or an acrylic acid ester copolymer resin emulsion copolymerized in the presence of a cationic surfactant and a nonionic surfactant. An emulsion-containing cement composition is disclosed in which a synthetic rubber emulsion such as SBR is mixed into cement. However, such conventional emulsion-mixed cement compositions tend to separate when used,
The so-called plastering workability such as pressing with a trowel is poor, and because a large amount of mixing water is required for plastering work, the concrete obtained after hardening has greater drying shrinkage than ordinary cement mixtures and is water resistant. Properties such as durability, alkali resistance, chemical resistance, and solvent resistance were not necessarily good. Furthermore, products containing emulsions copolymerized in the presence of anionic surfactants and nonionic surfactants can improve the surface precision of glass fiber-containing cement boards, asbestos cement boards, decorative plywood, metal surfaces, etc. The disadvantage was that the adhesion to the substrate was not good. The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an emulsion-mixed cement composition that does not have the above-mentioned drawbacks. To achieve this objective, the inventors
As a result of various studies, regarding the emulsion mixture used for mixing into the cement, when synthetic resin emulsions obtained by a specific manufacturing method were mixed into cement in appropriate combinations and amounts,
It was discovered that the above-mentioned drawbacks can be solved, and the present invention was completed. For such purposes, the emulsion-mixed cement composition of the present invention comprises: in the mixed presence of a nonionic surfactant and a directly linked cationic surfactant;
A synthetic resin emulsion obtained by emulsion polymerization of at least one acrylic ester monomer having an alkyl group having 3 or less carbon atoms and at least one methacrylic ester monomer is mixed into cement. It is characterized by Hereinafter, the configuration of the present invention will be explained in detail. As the nonionic surfactant used in the present invention, ethylene oxide type, diethanolamine type, anhydrosorbitol type, glucoside-gluconamide type, etc. can be used as needed.
These should be those that coexist stably with the cationic surfactants described below. Next, the directly linked cationic surfactant is a quaternary ammonium salt represented by formula I, where R ₁ ,
R ₂ , R ₃ and R ₄ represent H, an alkyl group, a hydroxyalkyl group, a urea-containing alkyl group or an amide bond-containing alkyl group. Examples of these cationic surfactants include alkyldimethylbenzylammonium chloride and alkyldimethylmethallylammonium chloride, which can be expressed by the following formulas. However, in the formula, R represents an alkyl group. The mixing ratio of nonionic surfactant and cationic surfactant should be approximately 1:0.03 to 0.5; if the cationic surfactant is less than this, the adhesion to any substrate will be poor. However, if it is used in excess, water resistance and chemical resistance tend to deteriorate. The amount of surfactant added during emulsion polymerization is 100% of the amount of synthetic resin monomer.
It is desirable that the amount is within 10 parts by weight. The synthetic resin monomer used in the present invention has 3 carbon atoms.
An acrylic ester and a methacrylic ester having the following alkyl groups are used together,
The mixing ratio of this is 0.3 to 3 moles of methacrylic ester per 1 mole of acrylic ester.
The acrylic esters are methyl acrylate, ethyl acrylate, propyl acrylate, and isopropyl acrylate, and the methacrylic esters are methyl methacrylate, ethyl methacrylate, propyl methacrylate, and isopropyl methacrylate. These synthetic resin monomers are necessarily emulsion polymerized to obtain a copolymer. In the blending ratio of the monomers mentioned above, when the amount of methacrylic acid is less than 0.3 moles or greater than 3 moles, the chemical resistance of the composition of the present invention tends to decrease, so the blending ratio must be strictly observed. . As described above, the emulsion of the present invention can be obtained through the above-mentioned emulsion polymerization using a specific surfactant within a certain range. The emulsion-mixed cement composition of the present invention comprises:
It is obtained by mixing the above-mentioned synthetic resin emulsion into hydraulic cement such as portland cement, slag cement, flyash cement, alumina cement, etc. When mixing, as a general rule, it should be done in an appropriate amount. The solid content of the synthetic resin emulsion is 5 to 5 parts by weight.
30 parts by weight. Of course, sand, coarse aggregate, admixtures, etc. commonly used in cement may be used. Experimental examples are illustrated below. Experimental Example [Emulsion Synthesis Method] A synthetic resin emulsion was synthesized using the monomers and surfactants shown in Table 1. [Preparation method of emulsion-mixed cement composition] As shown in Table 2, the above emulsion, cement, and aggregate were blended to prepare an emulsion-mixed cement composition, and performance tests were conducted using the following test method. The results are shown in Table 2. [Test method for emulsion-containing cement compositions] Trowel workability: Compare with the composition of Formulation 1 using a plastering trowel.Alkali resistance: Immerse in a saturated calcium hydroxide aqueous solution for 96 hours and observe the appearance. Volatile oil property: According to the test method specified in JIS K 5400, immerse in volatile oil No. 1 for 48 hours and observe the appearance.Bending strength: According to the bending strength test specified in JASS 23 M-103.Impact resistance: JASS 23 M Adhesion: According to the impact resistance test specified in JASS 23 M-103 Adhesion to smooth surface: In the adhesion test, marble ground with #140 abrasive paper was used as the base.

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[Table] Deterioration *2: Swelling, causing cracks, blisters, etc.

Claims (1)

[Claims] 1. Nonionic surfactant and quaternary ammonium salt cationic surfactant represented by the following formula I [However, R ₁ , R ₂ , R ₃ , and R ₄ represent H, an alkyl group, a hydroxyalkyl group, a urea-containing alkyl group, or an amide bond-containing alkyl group. ] At least one acrylic acid ester monomer having an alkyl group having 3 or less carbon atoms in the mixed presence of
at least one of a species and a methacrylic acid ester monomer
A cement composition containing a synthetic resin emulsion having a water-reducing effect obtained by emulsion polymerizing a mixture of acrylic acid ester and methacrylic acid ester in a molar ratio of 1:0.3 to 3. 2. The emulsion-containing cement composition according to claim 1, wherein the synthetic resin emulsion and cement are mixed in a solid content ratio of 5 to 30 parts by weight per 100 parts by weight of cement.