JPH04119955A - Dispersant of cement - Google Patents

Abstract

PURPOSE:To obtain the dispersant of cement which is excellent in action for enhancing fluidity of cement composition and water reducing properties, etc., by constituting the dispersant of cement while keeping high molecular sulfonate and/or carbonate, polyoxyethylene alkylphenyl ether and a defoaming agent as essential components. CONSTITUTION:The dispersant of cement is produced by mixing (A) high molecular sulfonate (e.g. salt of naphthalene sulfonic acid formaline condensate) and/or high molecular carboxylate, (B) polyoxyethylene alkylphenyl ether (e.g. polyoxyethylene nonylphenyl ether) and (C) a defoaming agent (e.g. a block copolymer of ethylene oxide and propylene oxide). This dispersant of cement is high in water reducing properties. Excellent fluidity is secured in the specified water-cement ratio by blending this dispersant with cement composition and also separation resistance of material is enhanced.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a cement dispersant that has excellent water-reducing properties and improves the flow characteristics of cement concrete. (Recently, it is possible to secure excellent fluidity at a certain water-cement ratio, and high-strength, high-durability concrete with excellent material separation resistance and hyper-performance concrete that does not require compaction are attracting attention.) It is possible to apply this technology to new concrete technologies that are currently undergoing rapid development.

(Conventional technology and its problems) In the field of cement concrete, large amounts of dispersants such as water reducers and high performance water reducers have been used. In general, lignin sulfonate-based and β-naphthalene sulfonate condensate-based products are used, and in recent years,
In connection with the research and development of high-strength concrete for high-rise RC and hyperformance concrete that does not require compaction, we aim to further improve the workability of cement concrete by improving the fluidity improvement effect and
The emergence of a cement dispersant with excellent material separation resistance is eagerly awaited.

On the other hand, it was proposed to use a nonionic surfactant having an oxyethylene chain and a β-naphthalene sulfonic acid formaldehyde condensate together as a slurry for self-leveling floor construction with excellent fluidity (Japanese Patent Laid-Open No. 55-23047
Publication No.).

However, there was a problem that the amount of air entrained was too large.

In addition, as self-leveling compositions and kits for producing such compositions, nonionic surfactants having an ether bond with an HLB value of 10 to 18, water reducing agents of polyoxynonylphenyl ether and naphthalene sulfonic acid formalin condensation, etc. are used in combination. A fluidizing agent was proposed (Japanese Patent Application Laid-Open No. 2-149
Publication No. 457).

However, when polyoxyethylene nonylphenyl ether and a water reducing agent are used together, there is a problem that the amount of air entrained increases, resulting in a significant decrease in strength.

As a result of various studies aimed at solving these problems, the present inventors have found that by combining a special surfactant, the effect of improving fluidity is further improved, and the provision of a cement dispersant that has excellent material separation resistance. The present inventors have discovered that this is possible and have completed the present invention.

(Means for Solving the Problems) That is, the present invention is a cement dispersant containing a polymer sulfonate and/or a polymer carboxylate, polyoxyethylene alkylphenyl ether, and an antifoaming agent as essential components.

The present invention will be further explained in detail below.

Examples of the polymer sulfonic acid salts according to the present invention include salts of naphthalene sulfonic acid formalin condensates, salts of alkylnaphthalene sulfonic acid formalin condensates, salts of melamine sulfonic acid formalin condensates, lignin sulfonates, and polymer lignin sulfonic acids. Examples include salt.

The polymer carboxylic acid salts according to the present invention include those obtained by adding alkylene oxide to a carboxyl group-containing polymer;
For example, Nippon Shokubai Chemical Co., Ltd. product name r600sJ, a hydrolyzate of a copolymer of olefin and ethylenically unsaturated dicarboxylic anhydride, a hydrolyzate of a copolymer of maleic anhydride and other comonomers, and Examples include slow-release polymers that are anhydrous and gradually hydrolyze with alkali from cement to improve the fluidity of cement.

The amount of the polymer sulfonate and/or polymer carboxylate used is 0.00 parts by weight in terms of active ingredient per 100 parts by weight of the hydraulic substance. O1 to 5.0 parts by weight is preferable, and 0.1 to 3.0 parts by weight.
0 part by weight is more preferable. If it is less than 0.01 parts by weight, the desired fluidity cannot be obtained, and if it exceeds 5.0 parts by weight, the setting delay will be large and material separation will become significant.

Examples of the polyoxyethylene alkylphenyl ether according to the present invention include polyoxyethylene nonylphenyl ether and polyoxyethylene octylphenyl ether, and among these, those having an HLB value of 15 to 20 are preferable.

The number of ethylene oxide groups in polyoxyethylene alkylphenyl ether varies depending on the amount of polyoxyethylene alkylphenyl ether used, the water-cement ratio, and other materials used, but the number of ethylene oxide groups in polyoxyethylene alkylphenyl ether is about 15 to 160. Preferably 70-1
00 is more preferred.

When the number of ethylene oxide groups is less than 15, air entrainment is large and it is difficult to control the amount of air.
If it exceeds this, the viscosity of the solution tends to increase when it is made into an aqueous solution, making it difficult to handle.

The amount of polyoxyethylene alkyl phenyl ether used is 0.15 to 5.0 parts by weight per 100 parts by weight of the hydraulic material.
0 parts by weight is preferred. If it is less than 0.15 parts by weight, there will be little effect on fluidity, and if it exceeds 5.0 parts by weight, there will be little effect on fluidity.

In particular, selecting the ratio of polymer sulfonate and/or polymer carboxylate to polyoxyethylene alkylphenyl ether in the range of 25:75 to 75:25 has the most significant effect of improving fluidity. ,preferable.

Examples of antifoaming agents according to the present invention include silicone-based, polyether-based, polyglycol-based, organic phosphoric acid-based, and amide-based antifoaming agents. In particular, a block copolymer with ethylene oxide containing propylene oxide at both ends,
By adding it, in addition to the defoaming effect, it also has the effect of improving the fluidity of cement concrete, which is more preferable.

The amount of antifoaming agent used is based on 100 parts by weight of the hydraulic substance.
0.01 to 5.0 parts by weight is preferred. If it is less than 0.01 parts by weight, the amount of air entrained will be large (and even if it exceeds 5.0 parts by weight, the defoaming effect will not change.

All of these are mixed with hydraulic substances, and depending on whether they are used for high-strength concrete, or even for high-strength concrete with ultrafine powder such as silica hume or blast furnace slag, or as a unit for aggregate countermeasures. The amount used varies greatly depending on whether it is used for the purpose of reducing water volume, etc.

Examples of the hydraulic substance include various Portland cements, various mixed cements, and cements mixed with various pozzolans such as silica hume and fly ash. Further, materials to which various admixtures such as expansion materials and rapidly hardening materials are added can also be used as hydraulic substances. Usually, this is combined with sand or gravel to form concrete.

In addition, the cement dispersant of the present invention can be used not only alone, but also as
It is also possible to use it in combination with other chemical admixtures.

The cement dispersant of the present invention is used for the purpose of improving the fluidity of cement concrete and reducing the water-cement ratio, and is particularly used for high-strength concrete and high-strength concrete using ultrafine powder, which require particularly high fluidity. Its utility value is particularly great for grouting materials, and even for hyper-performance concrete, which has been proposed recently.

(Example) The present invention will be explained below with reference to Examples.

Example 1 In a mortar with a water-cement ratio of 40% and a sand-cement ratio of 2, various ingredients were mixed as shown in Table 1 to form a mini-slump with a height of 15 cm, a bottom diameter of ioam, and a top diameter of 5 countries. A slump test was conducted using a cone, and the flow value was measured. Stirring was performed according to JIS R5201. The results are also listed in Table-1.

Materials used: Cement: A mixture of three brands of ordinary Portland cement made by Chichibu, Onoda, and Chichibu.Aggregation agent: A 6:4 mixture of Sumo Tsuki and Kisarazu.Component A.
: Polymer sulfonate, Daiichi Kogyo Seiyaku ■Product name "Cellflow 110PJ, main component salt of alkylnaphthalene sulfonic acid formalin condensate Component B1: Polyoxyethylene alkylphenyl ether, NOF ■Product name rNS
-270'', main component polyoxyethylene nonylphenyl component C -thyl (HLB 18.7, number of ethylene oxide groups 70): Antifoaming agent, manufactured by BASF, product name 1'RPE 3110J
A polymeric surfactant containing propylene groups at both ends, a buoylock copolymer of ethylene oxide and propylene oxide Table 1: No material separation in either case.

Example 2 As shown in Table 2, the same procedure as Example 1 was carried out except that the type of polyoxyethylene alkylphenyl ether was changed. The results are also listed in Table-2.

Materials used> Component B2: Polyoxyethylene alkyl phenyl ether, NOF Product name rNS-215J, main component polyoxyethylene nonylphenyl ether (HLB 1
5.0, Ethylene oxide group component B: Dai-Kogyo Seiyaku refined product name "Emulgit 100" main component polyoxyethylene nonylphenyl ether (HLB 19.1
．． Ethylene oxide group 100) Component B4: Daiichi Kogyo Seiyaku ■, product name "Emulgit 161J main component polyoxyethylene nonylphenyl ether (HLB 19.4, ethylene oxide group 16)"
1) Table Example 3 Example 1 except that component A was 0.6 parts by weight, component B was 0.633 parts by weight, and component C was 0.17 parts by weight, and the number of ethylene oxide groups in component B was changed. I did the same thing. The results are also listed in Table-3.

Example 4 without surface material separation The same procedure as Example 1 was carried out except that the formulation was as shown in Table 4. The results are also listed in Table-4.

<Materials used> Component A2: Takemoto Oil ■Product name rHP-8. +Main component polymer carboxylate component A: Product name 00S manufactured by Nippon Shokubai Kagaku Co., Ltd., Main component polymer carboxylate component A4: Nippon Sika ■ Packing product name rFF86. +Salt Table of Main Component Melamine Sulfonic Acid Formalin Condensate Example 5 Example 1 Experiment Nα1-7 was conducted in the same manner as in Example 1 except that component C was changed.

Materials used> Component C2: Toshiba Silicone Co., Ltd. trade name rTSA 732
J Silicone component Cs: Manufactured by BASF, product loading RPE 2510
J Polymer surfactant containing propylene oxide at both ends Component C4: manufactured by BASF Product loading RPE 2110 J Polymer surfactant containing propylene oxide at both ends No material separation in either case Example 6 Table 6 The same procedure as in Example 1 was carried out except that the ingredients were blended as shown. The results are also listed in Table-6.

Table 6 (Effects of the Invention) By using the cement dispersant of the present invention, it became possible to significantly improve the fluidity of cement concrete without material separation.

Patent applicant: Denki Kagaku Kogyo Co., Ltd.

Claims (1)

[Claims] (1) A cement dispersant containing a polymer sulfonate and/or a polymer carboxylate, polyoxyethylene alkylphenyl ether, and an antifoaming agent as essential components.