JP7020722B2 - Antifoaming agent for hydraulic composition, additive for hydraulic composition, and hydraulic composition - Google Patents

Description

The present invention relates to a defoaming agent for a water-hard composition, an additive for a water-hard composition, and a water-hard composition. More specifically, the present invention has excellent compatibility with a dispersant and is high even with a small amount of addition. The present invention relates to a defoaming agent for a water-hardening composition exhibiting defoaming performance, an additive for a water-hardening composition containing the defoaming agent for the water-hardening composition, and a water-hardening composition containing a defoaming agent for the water-hardening composition. It is a thing.

Conventionally, a hydraulic composition has been obtained by kneading a hydraulic binder and various materials such as water, filling the mold, curing the mold, and then removing the mold to obtain a cured product. In particular, a concrete composition, which is a kind of hydraulic composition, is prepared by mixing and kneading various materials such as cement, water, aggregate, and a dispersant, and then pouring it into a pre-prepared mold and placing it. It is manufactured by curing for a predetermined time. The concrete composition has excellent properties such as strength and durability, and is widely adopted in various buildings and building structures by taking advantage of the properties.

Here, in the concrete composition, an additive (additive for hydraulic composition) may be generally added in order to improve air entrainment and fluidity at the time of kneading various materials. By using such an additive, good dispersibility can be maintained even when the water content of the concrete composition is reduced. In addition, the handleability (workability) at the time of kneading and construction can be improved. Therefore, it is possible to construct a concrete composition or the like having excellent stability over time and workability as well as improving the durability and strength of the concrete composition.

Particularly in recent years, polycarboxylic acids have been used as dispersants that can be uniformly mixed and kneaded by enhancing the dispersibility of various materials of the hydraulic composition in the additives for the hydraulic composition added to the hydraulic composition. It is known to use a system dispersant. By using a polycarboxylic acid-based dispersant, the water reduction of the hydraulic composition can be enhanced. On the other hand, although the air entrainment property can be improved by using the polycarboxylic acid-based dispersant, the bubble diameter of the bubbles generated during kneading becomes large, which may affect the construction work. In order to solve such a problem, a so-called AE agent (Air Entraining agent) is used in combination in order to generate fine and high-quality bubbles and improve the freeze-solubility.

At this time, when the polycarboxylic acid-based dispersant and the AE agent are used in combination, a defoaming agent (a defoaming agent for a water-hard composition) is generally used for the purpose of eliminating a large number of bubbles generated by the AE agent or the like. Sometimes. For example, a concrete composition containing a polyoxyalkylene compound, cement, water, fine aggregate and coarse aggregate as essential components is known (see Patent Document 1). In the concrete composition, the polyoxyalkylene compound has "0.15 <u", where the total number of moles of oxyethylene groups added in the oxyalkylene group is u and the total number of moles of oxyalkylene groups having 3 or more carbon atoms is v. It satisfies the relationship of / (u + v) <0.9 "and has at least one aliphatic hydrocarbon group having 5 or more consecutive carbon atoms in the molecule. This has the advantage of suppressing an increase in the amount of air due to the extension of the kneading time and keeping the amount of air entrained stable. As a result, it becomes possible to provide a high-quality concrete composition having excellent durability and strength.

That is, conventionally, it has been considered that a highly hydrophobic defoaming agent is preferable as a defoaming agent in a concrete composition, but by improving the hydrophilicity of the polyoxyalkylene compound by the oxyethylene group, air by an AE agent or the like is used. It is possible to effectively suppress the generation of bubbles and suppress the increase in the amount of air due to the extension of the kneading time. As a result, there is no increase in the amount of air, and the amount of air entrained can be stabilized.

Japanese Patent Application Laid-Open No. 2003-226565

On the other hand, in the case of the general polyoxyalkylene compound disclosed in the above-mentioned Patent Document 1 and the like, the following problems may occur. Since the defoaming agent for a water-hard composition exhibits a defoaming effect sharply with a smaller amount of addition than the polycarboxylic acid-based dispersant used at the same time, the polycarboxylic acid-based dispersion is used to prevent a weighing error in the measuring device. A method of mixing with an agent in advance and liquefying it is planned. However, the polyoxyalkylene compound may have a problem of "compatibility" with the polycarboxylic acid-based dispersant. That is, there is a problem that the polycarboxylic acid-based dispersant and the defoaming agent are mixed and then changed with time, so that both of them return to a separated state. In this case, it is difficult to control the amount of air due to the uneven presence of the defoaming agent in the storage tank, and it is not possible to obtain a hydraulic composition with a stable amount of air for each kneading. The strength and the like may be biased, and it may be difficult to stably obtain a hydraulic composition having excellent durability and strength.

In the case of the polyoxyalkylene compound shown in Patent Document 1 above, the compatibility with the polycarboxylic acid-based dispersant was relatively good. However, in order to exhibit high defoaming performance by the polyoxyalkylene compound, it is necessary to mix them in a relatively high ratio in the hydraulic composition. That is, the amount of the polyoxyalkylene compound added (used amount) may increase. As a result, the amount of the defoaming agent added may be larger than usual, and the cost of the hydraulic composition may be increased accordingly.

As a result of diligent research to solve the above problems, the applicant of the present application has oxyethylene constituting the polyoxyalkylene compound in the polyoxyalkylene compound used as a defoaming agent for a water-hardening composition. A good phase with the polycarboxylic acid-based dispersant by optimizing the molar ratio of the groups and the total number of moles of the oxyethylene groups constituting the polyoxyalkylene compound and the oxyethylene groups having 3 to 18 carbon atoms. It is composed of a defoaming agent for a water-hard composition and a defoaming agent for the water-hard composition, which is soluble and exhibits high defoaming performance even if the amount of the defoaming agent itself is small. We have found an invention relating to a water-hardening composition prepared by containing an additive for a water-hardening composition and a defoaming agent for these water-hardening compositions.

Therefore, in view of the above circumstances, the present invention has good compatibility with a polycarboxylic acid-based dispersant, and is water-hardness that exhibits high defoaming performance even if the amount of the defoaming agent itself added is small. An object of the present invention is to provide a defoaming agent for a composition, an additive for a water-hardening composition, and a water-hardening composition.

According to the present invention, the following antifoaming agents for hydraulic compositions, additives for hydraulic compositions, and hydraulic compositions are provided.

[1] A defoaming agent for a water-hard composition used as an additive for a water-hard composition containing an essential component of a defoaming agent for a water-hard composition, a polycarboxylic acid-based dispersant, and water.
A polyoxyalkylene compound represented by the following general formula (1), wherein the compound is represented by the following general formula (1).
First condition: 0.16 ≦ n / (p + n + m) ≦ 0.40, and
Second condition: 20≤p + n + m≤48
A defoaming agent for hydraulic compositions that satisfies the relationship.
RO- (AO) p- (EO) n- (AO) m-H ... (1)
(However, R indicates an alkyl group or an alkenyl group having 8 to 30 carbon atoms and exhibits either a linear or branched structure. AO is an oxyalkylene group having the same or different carbon atoms of 3 to 18 carbon atoms. EO indicates an oxyethylene group. P, n, and m indicate the average number of added moles, respectively, and p is 0 to 2.0 , n is 1 or more, and m is 1 or more.)

[2] R in the general formula (1) is an alkyl group or an alkenyl group having 14 to 22 carbon atoms, and the total amount of R is a residue obtained by removing a hydroxy group from an unsaturated and / or branched primary alcohol. The defoaming agent for a water-hard composition according to [1], which contains 50% by mass or more with respect to the above.

[3] The defoaming agent for a hydraulic composition according to [1] or [2], wherein the AO in the general formula (1) is an oxypropylene group.

[4] The defoaming agent for a hydraulic composition according to any one of [1] to [3], wherein the first condition further satisfies the condition of 0.16 ≦ n / (p + n + m) ≦ 0.38.

[5] The defoaming agent for a hydraulic composition according to any one of [1] to [4], wherein the second condition further satisfies the condition of 24 ≦ p + n + m ≦ 40.

[6] The defoaming agent for a hydraulic composition according to any one of [1] to [5], wherein R in the general formula (1) has 14 to 22 carbon atoms.

[7] The defoaming agent for a water-hard composition according to any one of [1] to [6], a polycarboxylic acid-based dispersant, and an additive for a water-hard composition containing water as an essential component.

[8] A hydraulic composition containing the additive for a hydraulic composition according to [7] and cement as essential components.

[9] A hydraulic composition containing the additive for a hydraulic composition according to [7] , cement, and an aggregate containing a fine aggregate and / or a coarse aggregate as essential components.

The defoaming agent for a water-hardening composition of the present invention has excellent compatibility with a dispersant such as a polycarboxylic acid-based dispersant, and can exhibit high defoaming performance with a small amount of addition. Further, by using the defoaming agent for the hydraulic composition or the additive for the hydraulic composition containing the defoaming agent for the hydraulic composition, a hydraulic composition having excellent durability and strength can be created. Can be done.

Hereinafter, embodiments of the defoaming agent for a hydraulic composition, the additive for a hydraulic composition, and the hydraulic composition of the present invention will be described. Here, the defoaming agent for a hydraulic composition of the present invention (hereinafter, simply referred to as "defoaming agent"), the additive for a hydraulic composition, and the hydraulic composition are limited to the following embodiments. It is not a thing, and changes, modifications, improvements, etc. can be made as long as it does not deviate from the scope of the present invention.

1. 1. Defoaming agent (defoaming agent for hydraulic composition)
The defoaming agent according to the embodiment of the present invention is a water-hardening agent used as an additive for a water-hardening composition containing an essential component of a defoaming agent for a water-hardening composition, a polycarboxylic acid-based dispersant, and water. A defoaming agent for a composition, which is a polyoxyalkylene compound represented by the following general formula (1).
First condition: 0.16 ≦ n / (p + n + m) ≦ 0.40, and
Second condition: 20≤p + n + m≤48
It satisfies the relationship of.
RO- (AO) p- (EO) n- (AO) m-H ... (1)

In the above general formula (1), "R" represents an alkyl group or an alkenyl group having 8 to 30 carbon atoms, and exhibits either a linear or molecular chain structure. Further, "AO" indicates an oxyalkylene group having the same or different carbon atoms of 3 to 18, and "EO" indicates an oxyethylene group. On the other hand, p, n, and m each indicate the average number of added moles, p is 0 or more (0 to 2.0 in the present invention) , n is 1 or more, and m is 1 or more.

That is, the defoaming agent of the present embodiment is a polyoxyalkylene compound represented by the above general formula (1), and has oxyethylene (EO) groups constituting the polyoxyalkylene compound and both ends of the EO group. The average number of added moles of the oxyalkylene (AO) group having 3 to 18 carbon atoms located is configured to satisfy both the first condition and the second condition shown above.

Here, R in the general formula (1) is an alkyl group or an alkenyl group having 8 to 30 carbon atoms, more preferably 14 to 22 carbon atoms, and exhibits either a linear or branched structure. It is a thing. In particular, R can use a residue obtained by removing the hydroxy group from the alcohol, and the alcohol that can be used is not particularly limited, and for example, octanol, nonaol, decanol, undecanol, dodecanol, tridecanol, and tetradecanol can be used. Knoll, pentadecanol, hexadecanol, heptadecanol, octadecanol, nonadecanol, eicosanol, heneicosanol, docosanol, tricosanol, tetracosanol, pentacosanol, hexacosanol, heptacosanol, octacosanol, nonacosanol and triacon Linear alkanols such as tanol; 2-ethylhexanol, 2-propylheptanol, 2-butyloctanol, 1-methylheptadecanol, 2-hexyloctanol, 2-hexyldecanol, isodecanol, isotridecanol, Branched alkanols such as 3,5,5-trimethylhexanol; octanol, nonenol, desenol, undesenol, dodecenol, tridecenol, tetradecenol, pentadecenol, hexadesenol, pentadecenol, hexadecenol, heptadecenol, octadecenol, nonadesenol, eisenol, docosanol, tetraconol. Linear alkenols such as pentacosenol, hexacosenol, heptacosenol, octacosenol, nonacocenol and triaconsenol; branched alkenols such as 2-ethylhexenol, 1-methylheptadecenol, isotridecenol and isooctadecenol, etc. Be done. Further, as the alcohol used as R, only one of the above listed alcohols may be used, or two or more kinds of alcohols may be used in combination.

Here, when the above alcohol is used, the number of carbon atoms is 14 to 22, and the residue obtained by removing the hydroxy group from the unsaturated and / or branched primary alcohol is contained in an amount of 50% by mass or more based on the total amount of R. It is particularly suitable to do so. This makes it possible to improve the defoaming performance of the hydraulic composition. In this case, the alcohol used is one that exhibits the properties of a liquid, and more preferably one that exhibits the properties of a liquid at 20 ° C. This makes it possible to satisfactorily mix the hydraulic composition with other materials such as the polycarboxylic acid-based dispersant described later at room temperature.

Further, specific examples of alcohols that can be used are higher alcohols derived from natural fats and oils, Calcor series (Kao), Conol series (New Japan Rika), Fineoxocol series (Nissan Chemical Industries), Neodoll series (Neo Doll series). Shell Chemicals), SAFOL series (SASOL), EXXAL series (Exxon Mobil) and the like. As described above, these alcohols are more preferably those that exhibit the properties of a liquid at 20 ° C.

On the other hand, the AO (oxyalkylene group) in the general formula (1) represents an oxyalkylene group having 3 to 18 carbon atoms. Examples of the oxyalkylene group having 3 to 18 carbon atoms include an oxypropylene group, an oxybutylene group, an oxyhexylene group, an oxyoctylene group, and an oxystyrene group. In particular, it is preferable to use AO as an oxypropylene group. As a result, the defoaming performance is high, and the compatibility with the polycarboxylic acid-based dispersant or the like can be stabilized.

In addition, in the defoaming agent of the present embodiment, the first condition in the general formula (1) may satisfy the condition of 0.16 ≦ n / (p + n + m) ≦ 0.38. That is, the range of the first condition described above may be narrower. On the other hand, the second condition in the general formula (1) may satisfy the condition of 24 ≦ p + n + m ≦ 40. That is, similarly to the first condition described above, the range of the second condition described above may be narrowed. Thereby, by further limiting the range of the first condition and / or the second condition, a defoaming agent exhibiting higher defoaming performance and excellent compatibility can be obtained.

2. 2. By using the additive for hydraulic composition and the defoaming agent shown above, the additive for hydraulic composition and the hydraulic composition can be obtained. Here, the additive for a hydraulic composition contains a polycarboxylic acid-based dispersant and water as essential components together with the above-mentioned defoaming agent. This makes it possible to obtain an additive for a water-hard composition having good compatibility with a defoaming agent and a polycarboxylic acid-based dispersant and having high defoaming performance. On the other hand, in the hydraulic composition, the additive for the hydraulic composition further contains cement as an essential component, or further contains cement and an aggregate as essential components. Since the additive for the hydraulic composition or the water contained in the hydraulic composition is well known, detailed description thereof will be omitted here. Further, as the aggregate contained in the water-hardening composition, fine aggregate such as sand and / or coarse aggregate such as gravel, crushed stone, granulated slag, and recycled aggregate can be appropriately used. Further, since the details of the polycarboxylic acid-based dispersant will be described later, the description thereof will be omitted here.

3. 3. Method for Producing Defoaming Agent (Polyoxyalkylene Compound) The manufacturing method for producing the defoaming agent (polyoxyalkylene compound) of the present embodiment is not particularly limited, and the defoaming agent (polyoxyalkylene compound) is produced by a known production method. be able to. For example, a polyoxyalkylene compound can be obtained by adding an alkylene oxide to an alcohol. Here, a catalyst can be used when adding the alkylene oxide, and the catalyst thereof includes alkali metals and alkaline earth metals, their hydroxides, alkali catalysts such as alcoholate, Lewis acid catalysts, and composite metals. It is possible to use a catalyst, preferably an alkaline catalyst.

Examples of alkaline catalysts that can be used include sodium, potassium, sodium potassium amalgam, sodium hydroxide, potassium hydroxide, sodium hydride, sodium methoxydo, potassium methoxydo, sodium ethoxydo, potassium ethoxide, potassium butoxide and the like. It can be, preferably sodium hydroxide, potassium hydroxide, sodium methoxydo, potassium methoxyd, potassium butoxide.

On the other hand, examples of Lewis acid catalysts that can be used include tin tetrachloride, boron trifluoride, boron trifluoride diethyl ether complex, boron trifluoride din-butyl ether complex, boron trifluoride tetrahydrofuran complex, and boron trifluoride. Examples thereof include boron trifluoride compounds such as boron phenol complex and boron trifluoride acetate complex.

These catalysts can be neutralized and removed after the addition reaction, while they may be contained as they are. When neutralizing the catalyst, it can be done by a well-known method. For example, when the catalyst is an alkaline catalyst, acids such as hydrochloric acid, sulfuric acid, methanesulfonic acid, phosphoric acid, acetic acid, lactic acid, citric acid and succinic acid, silicates such as aluminum silicate and magnesium silicate, and activated clay are used as neutralizing agents. , Acidic clay, silica gel, acidic ion exchange resin and other adsorbents can be used.

Further, specifically explaining neutralization, examples of commercially available adsorbents include Kyoward 600 and 700 (trade names: Kyowa Chemical Industry Co., Ltd.), Mizuka Life P-1, P-1S, P-1G, and F. Silicates such as -1G (trade name: Mizusawa Chemical Industry), Tomita-AD600, 700 (trade name: Tomita Pharmaceutical); Diaion (trade name: Mitsubishi Chemical), Amberlist, Amberlite, Dowex (each) An ion exchange resin or the like such as trade name: Dow Chemical) can be used. Only one kind of these neutralizing agents may be used, or two or more kinds thereof may be used in combination.

The neutralized salt (neutralization product) produced by the neutralization of the catalyst can be further solid-liquid separated. As a method for solid-liquid separation of the neutralized salt, for example, a well-known method such as filtration or centrifugation can be used. Here, the solid-liquid separation by filtration is performed by using, for example, a filter paper, a filter cloth, a cartridge filter, a two-layer filter of cellulose and polyester, a metal mesh type filter, a metal sintered type filter, etc., and the temperature is reduced or pressurized. It can be carried out under the condition of 20 to 140 ° C. On the other hand, the solid-liquid separation by centrifugation can be carried out using, for example, a centrifuge such as a decanter or a centrifugal clarifier. If necessary, about 1 to 30 parts by mass of water can be added to 100 parts by mass of the solution before solid-liquid separation. As the solid-liquid separation, especially when performing filtration, it is more preferable to use a filtration aid because the filtration rate is improved.

The filtration aid used for filtration is not particularly limited, and for example, each series of Celite, High Flow Supercell, and Cellpure (trade name: Advanced Minerals Corporation), silica # 645, silica # 600H, silica # Diatomaceous earth such as 600S, silica # 300S, silica # 100F (trade name: central silica), daicalite (trade name: Grefco); Rocahelp (trade name: Mitsui Metal Mining), Topco (trade name: Showa Kagaku), etc. Examples thereof include pearlite; a cellulose-based filtration aid such as KC Flock (trade name: Nippon Paper), Fibracell (Advanced Generals Corporation); silica gel such as silopute (trade name: Fuji Silicia Chemical). Further, only one kind of the above-mentioned filtration aid may be used, or two or more kinds thereof may be used in combination.

Further, known polycarboxylic acid-based dispersants can be used. For example, a copolymer containing a monomer represented by the following general formula (2) and an unsaturated carboxylic acid-based monomer can be mentioned.

R ¹ -O-A-R ² ... (2)
(However, in the general formula (2), R ¹ represents an alkenyl group having 2 to 5 carbon atoms or an unsaturated acyl group having 3 or 4 carbon atoms, and A is 1 of an oxyalkylene group having 2 to 4 carbon atoms. It is a (poly) oxyalkylene unit having an average addition mole number of 1 to 500, which is composed of seeds or two or more kinds, and R ² is a hydrogen atom, an alkyl group having 1 to 22 carbon atoms, or a fat having 1 to 22 carbon atoms. Indicates a group acyl group.)

Examples of the unsaturated carboxylic acid-based monomer include (meth) acrylic acid, crotonic acid and the like as monocarboxylic acid-based monomers and salts thereof, and maleic acid, itaconic acid, fumaric acid and the like as dicarboxylic acid-based monomers. And its salt. Of these, (meth) acrylic acid, maleic acid and salts thereof are preferable. The salt is not particularly limited, and examples thereof include alkali metal salts such as sodium and potassium, alkaline earth metal salts such as magnesium and calcium, metal salts with aluminum and iron, ammonium salts, and amine salts.

The copolymer may be obtained by reacting any suitable monomer (third monomer) in addition to the above-mentioned monomer and unsaturated carboxylic acid-based monomer to obtain a copolymer. good. At this time, as the third monomer, for example, (meth) allylsulfonic acid and a salt thereof, (meth) acrylamide, acrylonitrile, (meth) acrylic acid ester and the like can be used.

Further, the polycarboxylic acid-based dispersant can be produced by a known method. Further, the copolymer can be produced by a known method. For example, the copolymer is synthesized by radical polymerization, and by mixing (heating) the above-mentioned monomer, unsaturated carboxylic acid-based monomer, and third monomer with a radical initiator. can get. Examples of the radical initiator used include persulfates such as potassium persulfate and ammonium persulfate, hydrogen peroxide, 2,2-azobis (2-amidinopropane) dihydrochloride, and azobisisobutyronitrile. These can also be used as a redox initiator in combination with reducing substances such as sulfites and L-ascorbic acid, as well as amines and the like. Further, in order to keep the mass average molecular weight of the obtained copolymer in a desired range, chain transfer agents such as 2-mercaptoethanol, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thioglycolic acid, mercaptoethanol and thioglycerin are used. It can also be used. Further, the polymerization may be carried out using water or an organic solvent as the solvent, or may be non-solvent.

Hereinafter, the defoaming agent of the present invention and the hydraulic composition containing the defoaming agent will be described based on the following examples and the like. The defoaming agent and the hydraulic composition of the present invention are not limited to the following examples. Since the conditions of the specific method (addition reaction, etc.) for producing the defoaming agent have already been described, detailed description thereof will be omitted here.

1. 1. Synthesis of antifoaming agent (polyoxyalkylene compound) First, an alcohol was used as R in the general formula (1) to synthesize an antifoaming agent (polyoxyalkylene compound). First, 130.7 g of alcohol A1 (“Angecol 85AN (trade name: Shin Nihon Rika)”) and 1.1 g of potassium hydroxide were put into a pressure vessel equipped with a stirrer, a pressure gauge, and a thermometer. Alcohol A1 (“Angecol 85AN”) has a melting point of about 11 ° C. and is in a liquid state at room temperature of around 20 ° C.

After dehydration treatment in this state, 217.8 g of ethylene oxide was press-fitted at a gauge pressure of 0.4 MPa over 1 hour while maintaining the reaction system in the pressure vessel at 110 ± 5 ° C., and then for 2 hours. Was aged. Further, while maintaining the above reaction system at 135 ± 5 ° C., 777.4 g of propylene oxide was press-fitted at a gauge pressure of 0.4 MPa over 5 hours, and then aged for 2 hours to complete the reaction.

Then, it was neutralized using "Kyoward 600 (trade name: Kyowa Kagaku Kogyo)" as an adsorbent, and purified by filtration to obtain a purified product. In this purified product, 10.1 mol of ethylene oxide and 27.2 mol of propylene oxide were added in order to 1.0 mol of lauryl alcohol based on the analysis results of NMR and gel permeation chromatography (mass average molecular weight in terms of polystyrene). Defoaming agent af-1 (polyoxyalkylene compound). The measurement conditions of NMR and gel permeation chromatography are shown below.

<Measurement conditions>
(1) NMR
Equipment: Varian Medical 300 (300MHz)
Nuclide: 1H, 13C
Solvent: CDCl3

(2) Gel permeation chromatography device: HLC-8120GPC (Tosoh)
Column: TSK gel Super H4000 + TSK gel Super H3000 + TSK gel Super H2000 (Tosoh)
Detector: Differential Refractometer (RI)
Eluent: Tetrahydrofuran Flow rate: 0.5 mL / min Column temperature: 40 ° C
Sample concentration: Eluent solution with sample concentration of 0.5% by mass Standard substance: Polystyrene (Tosoh)

The type of alcohols A1 to A5 used, the alkylene oxide (oxypropylene group), the order of addition in the addition reaction, the amount of addition, etc. were changed, and the defoaming agent af-1 was prepared according to the conditions shown in Table 1 below. The same treatment as in the synthesis was carried out to synthesize various antifoaming agents af-2 to af-9 and af-e1 to af-e3. Table 2 below summarizes the detailed characteristics and properties (straight / branched chain, saturated / unsaturated, carbon number, etc.) of the alcohols A1 to A5 used in the synthesis of the defoaming agent. show.

In Table 1 above, the defoaming agents af-1 to af-9 are synthesized so as to satisfy both the first condition and the second condition in the defoaming agent of the present invention. On the other hand, the defoaming agents af-e1 and af-e3 deviate from the first condition, while the defoaming agent af-e2 deviates from the second condition for comparison with af-1 and the like. It is a synthetic one.

2. 2. Synthesis of Copolymer Used for Polycarboxylic Acid Dispersant (1) Production Example 1 (Production of Copolymer PC-1)
Ion-exchanged water 140.1 g, α-methacryloyl-ω-methoxy-poly (n = 9) oxyethylene 163.0 g, methacrylic acid 28.8 g, 3-mercaptopropionic acid 3.8 g, 30% sodium hydroxide aqueous solution 9. 9 g was charged in a reaction vessel equipped with a thermometer, a stirrer, a dropping funnel, and a nitrogen introduction tube, and after uniformly dissolving while stirring, the atmosphere was replaced with nitrogen, and the temperature of the reaction system was set to 60 ° C. in a warm water bath. .. Next, 63.9 g of a 3.0% aqueous sodium persulfate solution was added to initiate a polymerization reaction. After 2 hours, 28.8 g of a 3.0% aqueous sodium persulfate solution was added and maintained at 60 ° C. for 2 hours to complete the polymerization reaction. This was adjusted to pH 6 by adding a 30% aqueous sodium hydroxide solution, and the concentration was adjusted to 40% with ion-exchanged water. This reaction product was designated as a copolymer (PC-1).

(2) Production Example 2 (Production of copolymer PC-2)
Ion-exchanged water 209.2 g, α-methacryloyl-ω-methoxy-poly (n = 45) oxyethylene 181.9 g, methacrylic acid 15.8 g, 3-mercaptopropionic acid 2.0 g thermometer, stirrer, dropping funnel After charging into a reaction vessel equipped with a nitrogen introduction tube and uniformly dissolving while stirring, the atmosphere was replaced with nitrogen, and the temperature of the reaction system was set to 60 ° C. in a warm water bath. Next, 27.7 g of a 1.0% hydrogen peroxide aqueous solution was added dropwise over 2.5 hours. Then, 7.1 g of a 1.0% hydrogen peroxide aqueous solution was added dropwise over 3.5 hours to complete the polymerization reaction. A 30% aqueous sodium hydroxide solution was added thereto to adjust the pH to 6, and the concentration was adjusted to 40% with ion-exchanged water. This reaction product was designated as a copolymer (PC-2).

(3) Production Example 3 (Production of copolymer PC-3)
94.2 g of ion-exchanged water was placed in a reaction vessel equipped with a thermometer, agitator, a dropping funnel, and a nitrogen introduction tube, and after uniformly dissolving while stirring, the atmosphere was replaced with nitrogen and the temperature of the reaction system was changed to a hot water bath. The temperature was set to 60 ° C. Next, 29.3 g of a 1.0% sodium persulfate aqueous solution was added dropwise over 3.5 hours, and at the same time, 11.7 g of methacrylic acid and α-methacryloyl-ω-methoxy-poly (n =) were added to 117.3 g of ion-exchanged water. 113) An aqueous solution in which 183.8 g of oxyethylene and 1.6 g of 3-mercaptopropionic acid were dissolved was added dropwise over 3.0 hours. After that, the temperature was maintained at 60 ° C. for 2 hours to complete the polymerization reaction. This was adjusted to pH 6 by adding a 30% aqueous sodium hydroxide solution, and the concentration was adjusted to 40% with ion-exchanged water. This reaction product was designated as a copolymer (PC-3).

(4) Production Example 4 (Production of copolymer PC-4)
82.6 g of ion-exchanged water and 175.7 g of α-metharyl-ω-hydroxy-poly (n = 113) oxyethylene were placed in a reaction vessel equipped with a thermometer, a stirrer, a dropping funnel, and a nitrogen introduction tube, and while stirring. After uniformly dissolving, the atmosphere was replaced with nitrogen, and the temperature of the reaction system was set to 60 ° C. in a warm water bath. Next, 9.8 g of a 10.0% hydrogen peroxide aqueous solution was added dropwise over 3.0 hours, and at the same time, an aqueous solution prepared by dissolving 11.7 g of acrylic acid and 7.8 g of hydroxyethyl acrylate in 97.6 g of ion-exchanged water was added. The aqueous solution was added dropwise over 3.0 hours, and at the same time, an aqueous solution prepared by dissolving 0.8 g of 3-mercaptopropionic acid and 1.0 g of ascorbic acid in 7.0 g of ion exchange was added dropwise over 4.0 hours. After that, the temperature was maintained at 60 ° C. for 0.5 hours to complete the polymerization reaction. This was adjusted to pH 4 by adding a 30% aqueous sodium hydroxide solution, and the concentration was adjusted to 40% with ion-exchanged water. This reaction product was designated as a copolymer (PC-4).

(5) Production Example 5 (Production of copolymer PC-5)
100.3 g of ion-exchanged water and 179.5 g of α- (3-methyl-3-butenyl) -ω-hydroxy-poly (n = 57) oxyethylene were provided with a thermometer, a stirrer, a dropping funnel, and a nitrogen introduction tube. After charging into a reaction vessel and uniformly dissolving while stirring, the atmosphere was replaced with nitrogen, and the temperature of the reaction system was set to 60 ° C. in a warm water bath. Next, 9.8 g of a 10.0% sodium persulfate aqueous solution was added dropwise over 3.0 hours, and at the same time, an aqueous solution prepared by dissolving 15.6 g of acrylic acid in 78.1 g of ion-exchanged water was added dropwise over 3 hours. At the same time, an aqueous solution prepared by dissolving 1.4 g of 3-mercaptopropionic acid and 1.0 g of ascorbic acid in 9.4 g of ion exchange was added dropwise over 4.0 hours. After that, the temperature was maintained at 60 ° C. for 0.5 hours to complete the polymerization reaction. This was adjusted to pH 4 by adding a 30% aqueous sodium hydroxide solution, and the concentration was adjusted to 40% with ion-exchanged water. This reaction product was designated as a copolymer (PC-5).

The mass average molecular weight of the copolymer was measured by gel permeation chromatography according to the measurement conditions shown below.

<Measurement conditions>
Equipment: Shodex GPC-101 (Showa Denko)
Column: OHpak SB-806M HQ + SB-806M HQ (Showa Denko)
Detector: Differential Refractometer (RI)
Eluent: 50 mM sodium nitrate aqueous solution Flow rate: 0.7 mL / min Column temperature: 40 ° C
Sample concentration: Eluent solution with sample concentration of 0.5% by mass Standard substance: Polyethylene glycol, polyethylene oxide (azilent)

Water was removed from the copolymers PC-1 to PC-5 produced by Production Examples 1 to 5, the solution was adjusted to a concentration of 5% using heavy water, and the measurement was performed by NMR at 300 MHz. went. As a result, it was confirmed that each monomer was polymerized to form a copolymer. Types of components (component A, component B (component B1, component B2)) used in the copolymers PC-1 to PC-5 produced in Production Examples 1 to 5, and their respective masses (%). The values of the mass average molecular weights of the respective copolymers PC-1 to PC-5 measured as described above are shown in Table 3 below.

In the description in Table 3 above, the following terms have the following meanings.
L-1: α-methacryloyl-ω-methoxy-poly (n = 9) oxyethylene L-2: α-methacryloyl-ω-methoxy-poly (n = 45) oxyethylene L-3: α-methacryloyl-ω- Methoxy-Poly (n = 113) Oxyethylene L-4: α-Metalyl-ω-Hydroxy-Poly (n = 113) Oxyethylene L-5: α- (3-Methyl-3-butenyl) -ω-Hydroxy- Poly (n = 57) Oxyethylene L-6: Hydroxyethyl acrylate M-1: Methacrylate M-2: Acrylic acid

3. 3. Preparation of polycarboxylic acid-based dispersant 2. The polycarboxylic acid-based dispersant SP obtained by diluting the polymers PC-1 to PC-5 produced by the above to a concentration of 20% in terms of pH using ion-exchanged water and a 30% sodium hydroxide aqueous solution, respectively. It was set to -1 to SP-12. Table 4 below shows a summary of the copolymers and pH used in the polycarboxylic acid-based dispersants.

4. Evaluation of compatibility between defoaming agent and polycarboxylic acid-based dispersant (1) Test method 1. Weigh 5 g each of the antifoaming agents af-1 to af-9 and af-e1 to af-e3 synthesized in 1. The polycarboxylic acid-based dispersants SP-1 to SP-12 prepared in the above were mixed with 1000 g. As a result, samples (mixtures) of Examples 1 to 20 and Comparative Examples 1 to 3 were prepared. Table 5 below summarizes the types of polycarboxylic acid-based dispersants and defoamers used in the samples (mixed solutions) of Examples 1 to 20 and Comparative Examples 1 to 3. Further, the sample (mixed solution) was stored in a constant temperature room until the temperature reached 30 ° C. Then, the sample that had been allowed to stand was taken out, and after sufficient stirring, compatibility was evaluated in a constant temperature room at 30 ° C.

(2) Compatibility evaluation method and evaluation result Here, the time immediately after stirring is set to 0 hour (measurement start time), and in Examples 1 to 20 and Comparative Examples 1 to 3, the mixed solution is a polycarboxylic acid-based dispersion. The time t until the agent SP-1 and the like and the defoaming agent af-1 and the like were separated from each other was visually confirmed every 6 hours, 12 hours, and 24 hours from the measurement start time.

The criteria for evaluating compatibility are
A: Separation is not confirmed even after 24 hours from the start of measurement (24 ≦ t)
B: Separation was confirmed within 12 hours or more and less than 24 hours (12 ≦ t <24).
C: Separation was confirmed within 6 hours or more and less than 12 hours (6 ≦ t <12).
D: Separation was confirmed in less than 6 hours (t <6)
And said. If it is C or higher, there is no practical problem. The evaluation results of this compatibility are shown in Table 5 below.

According to this, the samples of Examples 1 to 20 using the defoaming agents af-1 to af-9 satisfying each condition such as the first condition and the second condition of the present invention were separated by 6 hours. Not confirmed (evaluation C or higher). That is, good compatibility with the polycarboxylic acid-based dispersant was shown. In particular, the unsaturated alcohol A1 having a linear structure having 16 to 18 carbon atoms (see Table 2) and the saturated alcohol A2 having a branched chain structure having 16 carbon atoms satisfying the first and second conditions (Table). The defoaming agents af-1, af-2, af-3, af-4, and af-7 formed using 2) are compatible with each other in terms of compatibility between the polycarboxylic acid-based dispersant and the defoaming agent. No separation was confirmed for "24 hours or more", and the evaluation was A. That is, it was confirmed that particularly good results were obtained by using an unsaturated alcohol having a linear structure or a saturated alcohol having a branched chain structure (Examples 1 to 15 and 18).

On the other hand, in the case of the linear structure and saturated alcohols A3 to A5, separation was confirmed in "6 hours or more and less than 12 hours" or "12 hours or more and less than 24 hours" (Examples 16, 17, 19, 20) Although there were almost no practical problems, it was evaluated as B or C. From the above results, it was shown that the first condition and the second condition of the present invention are satisfied, and that the alcohol has 14 to 22 carbon atoms and the unsaturated and / or branched primary alcohol is used.

Further, in the case of the defoaming agent af-e1 not satisfying the first condition and the defoaming agent af-e2 not satisfying the second condition, separation was confirmed in less than 6 hours, and the evaluation was D. Thereby, in the defoaming agent of the present invention, the polycarboxylic acid-based dispersion by satisfying both the first condition and the second condition in the defoaming agent (polyoxyalkylene-based compound) represented by the general formula (1). It has been shown to have significant compatibility with the agent. Although the defoaming agent af-e3 did not satisfy the first condition, the evaluation regarding compatibility was good (evaluation A). However, since the evaluation of the defoaming performance described later is low, it is classified here as Comparative Example 3.

5. Effect of defoaming performance by defoaming agent Next, the effect of defoaming performance of various synthesized defoaming agents such as af-1 (polyoxyalkylene compound) was confirmed. First, a concrete composition was prepared as shown below.

(1) Preparation of concrete composition A 55 L forced twin-screw mixer with ordinary Portland cement (Taiheiyo Cement, Ube-Mitsubishi Cement, Sumitomo Osaka Cement. Here, equal amounts of the above three brands are mixed, specific gravity = 3.16). Fine aggregate (Oigawa water-based sand, specific gravity = 2.58) and coarse aggregate (Okazaki crushed stone, specific gravity = 2.66) are sequentially added as aggregates at the blending ratios shown in Table 6 and empty for 10 seconds. After kneading, apply the AE agent "AE-300 (trade name: Takemoto Oil and Fat)" to the cement so that the slump is 18 ± 2.5 cm and the air volume is 4.5 ± 0.5%. 0.0025% by mass, the polycarboxylic acid dispersants SP-1, SP-3, SP-12 shown in Table 4 and the defoaming agents af-1 to af-9, af-e3 shown in Table 2 are described below. With the types shown in Table 8, the addition amount was adjusted, and the mixture was added together with the kneading water and kneaded for 90 seconds. Here, the defoaming agent af-1 and the like and the polycarboxylic acid-based dispersant SP-1 and the like are regarded as part of the kneading water. Similarly, the polycarboxylic acid-based dispersants SP-5 and SP-9 shown in Table 4 and the defoaming agents af-1 to af-9 and af-e3 shown in Table 2 are used in the blending ratios shown in Table 7. Kneading was carried out using the types shown in Table 9 below.

(2) Effect of defoaming performance For the concrete composition immediately after kneading, the "air amount (%)" was measured in accordance with JIS-A1128. The amount of air (%) indicates the volume% in the hydraulic composition. Further, at the same time as the measurement of the above-mentioned air amount (%), the "slump (cm)" was measured according to JIS-A1101. The effect of the defoaming performance of the defoaming agent was confirmed by these air amounts (%). The measurement results of the air amount (%) and the slump (cm) are shown in Tables 8 and 9 below.

According to this, it was confirmed that the defoaming agents af-1 to af-9 satisfying the first condition and the second condition in the present invention all exhibit good defoaming performance (Examples 21 to 44). .. On the other hand, when the defoaming agent af-e3 synthesized for comparison was used, it was confirmed that the defoaming effect was significantly reduced as compared with af-1 to af-9 (Comparative Examples 4 to 4). 8). In af-e3, even if the addition amount (mass% / dispersant) to the polycarboxylic acid-based dispersant exceeds 1.00, the air amount (%) shows 10% or more, so that more addition is performed. There wasn't. That is, when the defoaming agent of the present invention is used as one of the essential components of a hydraulic composition, it can exhibit high defoaming performance even with a small amount of defoaming agent added, in addition to the compatibility already described. confirmed.

According to the defoaming agent for hydraulic composition of the present invention, it can be used as a defoaming agent when preparing a hydraulic composition. Further, according to the additive for a hydraulic composition of the present invention, it can be used as an additive when preparing a hydraulic composition. The water-hardening composition of the present invention is used in various buildings and building members of building members by using a defoaming agent having excellent compatibility with a dispersant and capable of exhibiting high defoaming performance with a small amount of addition. It can be used beneficially.

Claims (9)

A defoaming agent for a water-hard composition, which is used as an additive for a water-hard composition containing water as an essential component, a defoaming agent for a water-hard composition, a polycarboxylic acid-based dispersant, and water.
A polyoxyalkylene compound represented by the following general formula (1), wherein the compound is represented by the following general formula (1).
First condition: 0.16 ≦ n / (p + n + m) ≦ 0.40, and
Second condition: 20≤p + n + m≤48
A defoaming agent for hydraulic compositions that satisfies the relationship.
RO- (AO) p- (EO) n- (AO) m-H ... (1)
(However, R indicates an alkyl group or an alkenyl group having 8 to 30 carbon atoms and exhibits either a linear or branched structure. AO is an oxyalkylene group having the same or different carbon atoms of 3 to 18 carbon atoms. EO indicates an oxyethylene group. P, n, and m indicate the average number of added moles, respectively, and p is 0 to 2.0 , n is 1 or more, and m is 1 or more.) R in the general formula (1) is
It is an alkyl group or an alkenyl group having 14 to 22 carbon atoms, and
The defoaming agent for a water-hard composition according to claim 1, wherein the residue obtained by removing the hydroxy group from the unsaturated and / or branched primary alcohol is contained in an amount of 50% by mass or more based on the total amount of R. The AO in the general formula (1) is
The defoaming agent for a hydraulic composition according to claim 1 or 2, which is an oxypropylene group. The first condition is
0.16 ≤ n / (p + n + m) ≤ 0.38
The defoaming agent for a hydraulic composition according to any one of claims 1 to 3, further satisfying the above-mentioned conditions. The second condition is
24 ≦ p + n + m ≦ 40
The defoaming agent for a hydraulic composition according to any one of claims 1 to 4, further satisfying the above-mentioned conditions. The defoaming agent for a hydraulic composition according to any one of claims 1 to 5, wherein R in the general formula (1) has 14 to 22 carbon atoms. The defoaming agent for a hydraulic composition according to any one of claims 1 to 6.
With polycarboxylic acid dispersants,
Additive for hydraulic composition containing water as an essential ingredient. The additive for a hydraulic composition according to claim 7 ,
A hydraulic composition containing cement as an essential ingredient. The additive for a hydraulic composition according to claim 7 ,
With cement,
A hydraulic composition containing fine aggregate and / or an aggregate containing coarse aggregate as an essential component.