CN112203997A

CN112203997A - Defoaming agent for hydraulic composition, additive for hydraulic composition, and hydraulic composition

Info

Publication number: CN112203997A
Application number: CN201880093998.0A
Authority: CN
Inventors: 内藤裕树; 古田章宏; 泽田阳; 冈田和寿
Original assignee: Takemoto Oil and Fat Co Ltd
Current assignee: Takemoto Oil and Fat Co Ltd
Priority date: 2018-05-30
Filing date: 2018-05-30
Publication date: 2021-01-08
Anticipated expiration: 2038-05-30
Also published as: JPWO2019229888A1; JP7020722B2; TW202003419A; CN112203997B; WO2019229888A1

Abstract

An antifoaming agent for a hydraulic composition, which is a polyoxyalkylene-based compound represented by the following general formula (1) and satisfies the following relationship: condition 1: 0.16 ≦ n/(p + n + m) ≦ 0.40, and condition 2: 20 ≦ p + n + m ≦ 48, RO- (AO) p- (EO) n- (AO) m-H · (1). Wherein R represents an alkyl group or an alkenyl group having 8 to 30 carbon atoms, and represents any one of a linear chain and a branched chain; AO represents the same or different oxyalkylene group having 3 to 18 carbon atoms; EO represents an oxyethylene group; p, n and m each represent an average molar number of addition, and p is 0 or more, n is 1 or more and m is 1 or more.

Description

Defoaming agent for hydraulic composition, additive for hydraulic composition, and hydraulic composition

Technical Field

The present invention relates to an antifoaming agent for a hydraulic composition, an additive for a hydraulic composition, and more particularly, to an antifoaming agent for a hydraulic composition which has excellent compatibility with a dispersant and can exhibit high antifoaming performance even when added in a small amount, an additive for a hydraulic composition containing the antifoaming agent for a hydraulic composition, and a hydraulic composition containing the antifoaming agent for a hydraulic composition.

Background

Conventionally, a hydraulic composition is a cured product obtained by kneading a hydraulic binder with various materials such as water, filling the kneaded material into a mold, curing the filled material, and then releasing the mold. In particular, a concrete composition, which is one of hydraulic compositions, is manufactured by mixing and kneading various materials such as cement, water, aggregate, and a dispersant, pouring the mixture into a previously prepared mold, and hardening the mixture for a predetermined time. Such a concrete composition has excellent properties such as strength and durability, and is widely used for various buildings and building structures by taking advantage of the properties.

Here, in the concrete composition, in the kneading process of kneading various materials, an additive (additive for hydraulic composition) is usually added in order to improve air flow-through property and fluidity. By using such additives, good dispersibility can be maintained even in the case where the moisture of the concrete composition has been reduced. Further, workability (workability) at the time of kneading or during construction can be improved. Therefore, the durability, strength, and the like of the concrete composition are improved, and a concrete composition having excellent stability over time and workability can be formed.

In particular, in recent years, it has been known that, in an additive for hydraulic compositions added to a hydraulic composition, a polycarboxylic acid-based dispersant is used as a dispersant to improve dispersibility of various materials of the hydraulic composition and to make mixing and kneading uniform. The use of the polycarboxylic acid-based dispersant can improve the water-reducing ability of the hydraulic composition. On the other hand, although good air circulation can be obtained by using a polycarboxylic acid dispersant, the bubble diameter of the bubbles generated at the kneading becomes large, and the construction work may be affected. In order to solve such a problem, a so-called AE agent (Air encapsulation agent) is used in combination to generate fine and excellent bubbles and improve the freeze solubility.

In this case, when the polycarboxylic acid-based dispersant and the AE agent are used in combination, an antifoaming agent (antifoaming agent for hydraulic compositions) is generally used in order to eliminate a large amount of air bubbles generated from the AE agent and the like. For example, a concrete composition containing a polyoxyalkylene compound, cement, water, a fine aggregate and a coarse aggregate as essential components is known (see patent document 1). In the concrete composition, when the total number of moles of oxyethylene groups added to oxyalkylene groups is u and the total number of moles of oxyalkylene groups having 3 or more carbon atoms added is v, the polyoxyalkylene-based compound satisfies the relationship "0.15 < u/(u + v) < 0.9" and has at least one aliphatic hydrocarbon group in which 5 or more carbon atoms are continuous in the molecule. This provides advantages of suppressing an increase in the amount of air with an increase in kneading time and stably maintaining the air flow rate. As a result, a high-quality concrete composition excellent in durability and strength can be provided.

That is, conventionally, it has been considered that a highly hydrophobic substance can be used as the defoaming agent in the concrete composition, but the generation of bubbles due to the AE agent and the like can be effectively suppressed by the improvement of the hydrophilicity due to the oxyethylene group of the polyoxyalkylene-based compound, and the increase of the air amount due to the extension of the kneading time can be suppressed. As a result, the air flow rate can be stabilized without increasing the air amount.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2003-226565

Disclosure of Invention

Problems to be solved by the invention

On the other hand, in the case of the conventional polyoxyalkylene-based compound disclosed in the above-mentioned patent document 1 and the like, the following problems may occur. Since the defoaming agent for hydraulic compositions can exert a defoaming effect sharply with a small amount of addition as compared with the polycarboxylic acid-based dispersant used simultaneously, a method of mixing the defoaming agent with the polycarboxylic acid-based dispersant in advance to form a single liquid has been attempted in order to prevent metering errors of a metering device. However, there is a problem of "compatibility" between the polyoxyalkylene compound and the polycarboxylic acid-based dispersant. That is, there is a problem that both the polycarboxylic acid-based dispersant and the defoaming agent return to a separated state due to a change with time after mixing. In this case, the defoaming agent is unevenly present in the storage tank, making it difficult to control the amount of air, and thus it is impossible to obtain a hydraulic composition having a stable amount of air at every kneading, and variations in strength and the like may occur depending on the kneading lot, and it is difficult to obtain a hydraulic composition having excellent durability and strength which is stable.

In the case of the polyoxyalkylene compound shown in patent document 1, the compatibility with the polycarboxylic acid dispersant is relatively good. However, in order to exhibit high defoaming performance by the polyoxyalkylene compound, it is necessary to mix the polyoxyalkylene compound in a hydraulic composition at a relatively high ratio. That is, the amount of the polyoxyalkylene compound to be added (amount to be used) is increased. As a result, the amount of the antifoaming agent added is increased compared to the usual amount, and the cost of the hydraulic composition may be increased.

As a result of intensive studies to solve the above problems, the present inventors have found that a polyoxyalkylene compound used as a defoaming agent for a hydraulic composition can be optimized in terms of the molar ratio of oxyethylene groups constituting the polyoxyalkylene compound and the total molar number of addition of oxyethylene groups constituting the polyoxyalkylene compound and oxyethylene groups having 3 to 18 carbon atoms, whereby a defoaming agent for a hydraulic composition according to the present invention having good compatibility with a polycarboxylic acid-based dispersant and exhibiting high defoaming performance even when the amount of the defoaming agent itself is small, an additive for a hydraulic composition comprising the defoaming agent for a hydraulic composition, and a hydraulic composition comprising the defoaming agent for a hydraulic composition and the like can be obtained.

In view of the above circumstances, an object of the present invention is to provide a defoaming agent for a hydraulic composition, an additive for a hydraulic composition, and a hydraulic composition, which have good compatibility with a polycarboxylic acid-based dispersant and can exhibit high defoaming performance even when the amount of the defoaming agent itself is small.

Means for solving the problems

According to the present invention, there are provided an antifoaming agent for a hydraulic composition, an additive for a hydraulic composition, and a hydraulic composition, which will be described below.

[1] An antifoaming agent for a hydraulic composition, which is a polyoxyalkylene-based compound represented by the following general formula (1) and satisfies the following relationship:

condition 1: 0.16 ≦ n/(p + n + m) ≦ 0.40, and

condition 2: 20 < p + n + m < 48,

RO-(AO)p-(EO)n-(AO)m-H···(1)，

wherein R represents an alkyl group or an alkenyl group having 8 to 30 carbon atoms, and represents either a straight chain or a branched chain. AO represents an oxyalkylene group having 3 to 18 carbon atoms, which may be the same or different, and EO represents an oxyethylene group. p, n and m each represent an average molar number of addition, and p is 0 or more, n is 1 or more and m is 1 or more.

[2] The antifoaming agent according to [1], wherein R in the general formula (1) is an alkyl group or alkenyl group having 14 to 22 carbon atoms, and the antifoaming agent contains 50% by mass or more of a residue obtained by removing a hydroxyl group from an unsaturated and/or branched primary alcohol, based on the total amount of R.

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

[4] The antifoaming agent according to any one of [1] to [3], wherein the above-mentioned condition 1 further satisfies a condition of 0.16 ≦ n/(p + n + m) ≦ 0.38.

[5] The antifoaming agent according to any one of [1] to [4], wherein the condition 2 further satisfies the condition of 24 ≦ p + n + m ≦ 40.

[6] The antifoaming 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] An additive for hydraulic compositions, which comprises the antifoaming agent for hydraulic compositions according to any one of [1] to [6], a polycarboxylic acid-based dispersant and water as essential components.

[8] A hydraulic composition comprising the antifoaming agent for hydraulic compositions according to any one of [1] to [6], a polycarboxylic acid-based dispersant and cement as essential components.

[9] A hydraulic composition comprising the antifoaming agent for hydraulic compositions according to any one of [1] to [6], a polycarboxylic acid-based dispersant, cement, and aggregate containing fine aggregate and/or coarse aggregate as essential components.

ADVANTAGEOUS EFFECTS OF INVENTION

The defoaming agent for hydraulic compositions of the present invention has excellent compatibility with dispersants such as polycarboxylic acid dispersants, and can exhibit high defoaming performance with a small amount of addition. Further, by using the defoaming agent for a hydraulic composition or an additive for a hydraulic composition containing the defoaming agent for a hydraulic composition, a hydraulic composition having excellent durability and strength can be produced.

Detailed Description

Hereinafter, the defoaming agent for hydraulic compositions, the additive for hydraulic compositions and the hydraulic composition according to the present invention will be described in detail with reference to the accompanying drawings. The antifoaming agent for hydraulic compositions (hereinafter, simply referred to as "antifoaming agent"), the additive for hydraulic compositions, and the hydraulic composition of the present invention are not limited to the following embodiments, and may be modified, revised, and improved without departing from the scope of the present invention.

1. Antifoaming agent (antifoaming agent for Hydraulic composition)

The defoaming agent of one embodiment of the present invention is a polyoxyalkylene-based compound represented by the following general formula (1), and satisfies the following relationship:

condition 1: 0.16 ≦ n/(p + n + m) ≦ 0.40, and

condition 2: 20 < p + n + m < 48,

RO-(AO)p-(EO)n-(AO)m-H···(1)。

in the general formula (1), "R" represents an alkyl group or an alkenyl group having 8 to 30 carbon atoms, and has either a straight chain or a branched structure. Further, "AO" represents the same or different oxyalkylene group having 3 to 18 carbon atoms, and "EO" represents an oxyethylene group. On the other hand, p, n and m each represent an average molar number of addition, and p is 0 or more, 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 is structured such that the average number of moles of oxyethylene (EO) groups constituting the polyoxyalkylene compound and oxyalkylene (AO) groups having 3 to 18 carbon atoms located at both ends of the EO groups added satisfies both the above-described 1 st condition and 2 nd condition.

In the general formula (1), R is an alkyl group or alkenyl group having 8 to 30 carbon atoms, more preferably 14 to 22 carbon atoms, and has either a straight chain or a branched chain structure. In particular, R may be a residue obtained by removing a hydroxyl group from an alcohol, and the alcohol to be used is not particularly limited, and examples thereof include straight-chain alcohols such as octanol, nonanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, hexadecanol, heptadecanol, octadecanol, nonadecanol, eicosanol, heneicosanol, docosanol, tricosanol, tetracosanol, pentacosanol, hexacosanol, heptacosanol, octacosanol, nonacosanol and triacontanol; branched alcohols such as 2-ethylhexanol, 2-propylheptanol, 2-butyloctanol, 1-methylheptanol, 2-hexyloctanol, 2-hexyldecanol, isodecanol, isotridecanol, and 3,5, 5-trimethylhexanol; linear enols such as octenol, nonenol, decenol, undecenol, dodecenol, tridecenol, tetradecenol, pentadecenol, hexadecenol, heptadecenol, octadecenol, nonadecenol, eicosenol, docosenol, ditetradecenol, pentacosenol, hexacosenol, heptacosenol, octacosenol, triacontenol, and triacontenol; or branched enols such as 2-ethylhexenol, 1-methylheptadecenol, isotridecanol, and isosteadecenol. As the alcohol used as R, only one kind of the above-listed alcohols may be used, or 2 or more kinds of alcohols may be used in combination.

When the above-mentioned alcohols are used, it is particularly preferable that the carbon number is 14 to 22 and the residue obtained by removing a hydroxyl group from an unsaturated and/or branched primary alcohol is contained in an amount of 50 mass% or more based on the total amount of R. This improves defoaming performance in the hydraulic composition. In this case, the alcohol used exhibits liquid properties, more preferably at 20 ℃. This makes it possible to mix the mixture well with other materials of the hydraulic composition such as a polycarboxylic acid dispersant described later at around room temperature.

Specific examples of alcohols that can be used include higher alcohols derived from natural oils and fats, KALCOL series (kajoke), CONOL series (new japanese physics and chemistry), FINEOXOCOL series (japanese chemical industry), NEODOL series (SHELL CHEMICALS), SAFOL series (SASOL), and EXXAL series (EXXON MOBIL). As mentioned above, more preferably, these alcohols also exhibit liquid properties at 20 ℃.

On the other hand, 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 oxyhexenyl group, an oxyoctenyl group, and an oxystyrene group. In particular, AO is preferably an oxypropylene group. This improves defoaming performance and stabilizes compatibility with a polycarboxylic acid dispersant and the like.

In the defoaming agent of the present embodiment, the condition 1 in the general formula (1) may satisfy the condition of 0.16 ≦ n/(p + n + m) ≦ 0.38. That is, the range of the above condition 1 may be made narrower. On the other hand, the condition 2 in the general formula (1) may satisfy the condition 24 ≦ p + n + m ≦ 40. That is, as in the case of the above condition 1, the range of the above condition 2 may be made narrower. By further limiting the range of the condition 1 and/or the condition 2, a higher defoaming performance can be exhibited and a defoaming agent having excellent compatibility can be obtained.

2. Additive for hard composition and hydraulic composition

By using the defoaming agent as described above, an additive for hydraulic compositions and a hydraulic composition can be obtained. The additive for hydraulic compositions contains a polycarboxylic acid dispersant and water as essential components in addition to the defoaming agent. Thus, an additive for hydraulic compositions having good compatibility with a defoaming agent and a polycarboxylic acid dispersant and high defoaming performance can be obtained. On the other hand, the hydraulic composition contains cement as an essential component, or cement and aggregate as essential components, in addition to the above-mentioned additive for hydraulic compositions. Since additives for hydraulic compositions or water contained in hydraulic compositions are well known, detailed description thereof will be omitted here. The aggregate contained in the hydraulic composition may be suitably fine aggregate such as sand, coarse aggregate such as gravel, crushed stone, granulated slag or recycled aggregate, or the like. The polycarboxylic acid-based dispersant is described in detail later, and therefore, the description thereof is omitted here.

3. Method for producing defoaming agent (polyoxyalkylene compound)

The method for producing the defoaming agent (polyoxyalkylene compound) of the present embodiment is not particularly limited, and a known production method can be used. For example, a polyoxyalkylene compound can be obtained by adding an alkylene oxide to an alcohol. Here, when the alkylene oxide is added, a catalyst can be used, and as the catalyst, a basic catalyst such as alkali metal and alkaline earth metal or hydroxide, alkoxide thereof, or a lewis acid catalyst, a composite metal catalyst can be used, and a basic catalyst is preferably used.

Examples of the basic catalyst that can be used include sodium, potassium, sodium potassium amalgam, sodium hydroxide, potassium hydroxide, sodium hydride, sodium methoxide, potassium methoxide, sodium ethoxide, potassium butoxide, etc., and sodium hydroxide, potassium hydroxide, sodium methoxide, potassium methoxide, and potassium butoxide are preferable.

On the other hand, examples of the lewis acid catalyst that can be used include, for example, tin tetrachloride, boron trifluoride diethyl ether complex, boron trifluoride di-n-butyl ether complex, boron trifluoride tetrahydrofuran complex, boron trifluoride phenol complex, boron trifluoride acetic acid complex, and other boron trifluoride compounds.

These catalysts can be neutralized and removed after the addition reaction, and on the other hand, they can be contained as they are. When the catalyst is neutralized, it can be carried out by a known method. For example, when the catalyst is a basic catalyst, acids such as hydrochloric acid, sulfuric acid, methanesulfonic acid, phosphoric acid, acetic acid, lactic acid, citric acid, and succinic acid; or silicates such as aluminum silicate and magnesium silicate; activated clay, acid clay, silica gel, acid ion exchange resin, and the like.

In addition, when the neutralization is specifically described, as commercially available adsorbents, for example, silicates such as KYOWAAD600, 700 (both trade names, Synergisic chemical industry), MIZUKALIFE P-1, P-1S, P-1G, F-1G (both trade names, Water chemical industry), TOMITA-AD600, 700 (both trade names, Futian pharmaceuticals) and the like; ion exchange resins such as DIAION (trade name, Mitsubishi CHEMICAL), AMBERLYST, AMBERLITE, DOWEX (both trade names, DOW CHEMICAL), and the like. Only 1 kind of these neutralizing agents may be used, or 2 or more kinds may be used in combination.

The neutralized salts (neutralized products) produced by the neutralization of the catalyst can be further subjected to solid-liquid separation. As a method for solid-liquid separation for neutralizing salts, for example, a known method such as filtration or centrifugal separation can be used. The solid-liquid separation by filtration can be carried out at a temperature of 20 to 140 ℃ under reduced pressure or increased pressure using, for example, a filter paper, a filter cloth, a cartridge filter, a 2-layer filter of cellulose and polyester, a metal mesh filter, a metal sintered filter, or the like. On the other hand, solid-liquid separation by centrifugal separation can be performed by using a centrifugal separator such as a decanter or a centrifugal clarifier, for example. If necessary, about 1 to 30 parts by mass of water may be added to 100 parts by mass of the solution before solid-liquid separation. The solid-liquid separation is more preferable, particularly when the filtration is performed, because the filtration rate is increased by using a filter aid.

Examples of the filter aid used for filtration include, but are not particularly limited to, diatomaceous earth such as diatomaceous earth, various series of hypo SUPER cel, CELL PURE (trade name, Advanced Minerals Corporation), silica #645, silica #600H, silica #600S, silica #300S, silica #100F (all trade names, center シリカ), white diatomaceous earth (trade name, GREFCO); perlite such as ROKAHELPR (trade name, Mitsui Metal mining industry), TOPCO (trade name, Showa chemical); cellulose-based filter aids such as KC-FLOCK (trade name, Japan paper), FIBERACELL (advanced Minerals corporation); silica gel such as SAIROPYUTO (trade name, Fuji SILYSIA Chemicals). In addition, only 1 kind of the above filter aid may be used, or 2 or more kinds may be used in combination.

In addition, known polycarboxylic acid dispersants can be used. For example, a copolymer including a monomer represented by the following general formula (2) and an unsaturated carboxylic acid monomer is exemplified.

R¹-O-A-R²···(2)

(wherein, in the general formula (2), R¹Represents an alkenyl group having 2 to 5 carbon atoms or an unsaturated acyl group having 3 or 4 carbon atoms, A is a (poly) oxyalkylene unit having an average addition mole number of 1 to 500 consisting of 1 or 2 or more species of oxyalkylene groups having 2 to 4 carbon atoms, R is a linear or branched alkylene oxide group²Represents a hydrogen atom, an alkyl group having 1 to 22 carbon atoms, or an aliphatic acyl group having 1 to 22 carbon atoms. )

Examples of the unsaturated carboxylic acid monomer include (meth) acrylic acid, crotonic acid, and salts thereof as monocarboxylic acid monomers, and maleic acid, itaconic acid, fumaric acid, and salts thereof as dicarboxylic acid monomers. Among them, (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 of aluminum and iron, ammonium salts, and amine salts.

The copolymer can be obtained by reacting the above-mentioned monomer with an unsaturated carboxylic acid-based monomer and any suitable monomer (third monomer) other than these. In this case, as the third monomer, for example, (meth) allylsulfonic acid and salts thereof, (meth) acrylamide, acrylonitrile, (meth) acrylate, and the like can be used.

The polycarboxylic acid-based dispersant can be produced by a known method. The copolymer can be produced by a known method. For example, the copolymer is synthesized by radical polymerization, and is obtained by mixing (heating) the above monomer, unsaturated carboxylic acid monomer, and third monomer with a radical initiator. Examples of the radical initiator to be used include persulfates such as potassium persulfate and ammonium persulfate, hydrogen peroxide, 2, 2-azobis (2-amidinopropane) dihydrochloride, azobisisobutyronitrile, and the like. These may be used as a redox initiator in combination with a reducing substance such as sulfite or L-ascorbic acid, and further with an amine. In addition, in order to make the mass average molecular weight of the copolymer obtained within a desired range, a chain transfer agent such as 2-mercaptoethanol, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thioglycolic acid, mercaptoethanol, thioglycerol, or the like can be used. In addition, water or an organic solvent may be used as a solvent for the polymerization, or a solvent may not be used.

Examples

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 antifoaming 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 is omitted here.

1. Synthesis of defoaming agent (polyoxyalkylene-based Compound)

First, an antifoaming agent (polyoxyalkylene-based compound) was synthesized using an alcohol as R in the general formula (1). First, 130.7g of an alcohol a1 ("UNJECOL 85AN (trade name, new japanese patent chemical) and 1.1g of potassium hydroxide were charged into a pressure vessel equipped with a stirrer, a manometer and a thermometer. The melting point of alcohol A1 ("UNJECOL 85 AN") is approximately 11 ℃ and is liquid at ordinary temperatures around 20 ℃.

After the dehydration treatment in this state, 217.8g of ethylene oxide was introduced thereinto under a gauge pressure of 0.4MPa for 1 hour while maintaining the reaction system in the pressure vessel at 110. + -. 5 ℃ and then aged for 2 hours. Further, 777.4g of propylene oxide was introduced thereinto under a gage pressure of 0.4MPa for 5 hours while maintaining the reaction system at 135. + -. 5 ℃ and then aged for 2 hours to complete the reaction.

Subsequently, neutralization treatment was performed using "KYOWAAD 600 (trade name, co-and chemical industry)" as an adsorbent, and filtration-purified to obtain a purified product. The purified product was an antifoaming agent af-1 (polyoxyalkylene-based compound) obtained by adding 10.1 moles of ethylene oxide and 27.2 moles of propylene oxide to 1.0 mole of dodecanol in this order, as a result of NMR and gel permeation chromatography (mass average molecular weight in terms of polystyrene) analysis. The measurement conditions of NMR and gel permeation chromatography are as follows.

< measurement conditions >

(1)NMR

The device comprises the following steps: varian Mercury 300(300MHz)

And (4) nuclear seed: 1H, 13C

Solvent: CDCl3

(2) Gel permeation chromatography

The device comprises the following steps: HLC-8120GPC (Chinese imperial ceramics ソー)

Column: TSK gel Super H4000+ TSK gel Super H3000+ TSK gel Super H2000 (Chinese imperial envoy ソー)

A detector: differential Refractometer (RI)

Eluent: tetrahydrofuran (THF)

Flow rate: 0.5 mL/min

Column temperature: 40 deg.C

Sample concentration: eluent solution with sample concentration of 0.5 mass%

Standard substance: polystyrene (Chinese imperial herbs ソー)

Various defoamers af-2 to af-9 and af-e1 to af-e3 were synthesized by changing the kind of the alcohols a1 to a5 used, alkylene oxide (oxypropylene group), the order of addition in the addition reaction, the amount of addition, and the like, and performing the same treatment as in the synthesis of the above defoamer af-1 under the conditions shown in table 1 below. Details of the characteristics and properties (linear/branched, saturated/unsaturated, and carbon number, etc.) of the alcohols a1 to a5 used for the synthesis of the antifoaming agent are summarized in table 2 below.

[ Table 1]

[ Table 2]

Using alcohols	Straight/branched chain	Saturated/unsaturated	Number of carbon atoms	Remarks for note
					A1	Straight chain	Unsaturated polyester	16-18	UNJECOL85AN (New Japanese physics and chemistry)
A2	Branched chain	Saturation of	16	ISOFOL16(SASOL)
					A3	Straight chain	Saturation of	18	KALCOL8098 (King of flowers)
A4	Straight chain	Saturation of	22	NACOL 22-98(SASOL)
					A5	Straight chain	Saturation of	12	1-dodecanol (KISHIDA CHECHEJI CHEN)

In the above Table 1, the defoaming agents af-1 to af-9 were synthesized in such a manner as to satisfy both the 1 st and 2 nd conditions of the defoaming agent of the present invention. In contrast, for comparison with af-1 and the like, defoamers af-e1 and af-e3 were synthesized so as not to satisfy condition 1, and defoamers af-e2 were synthesized so as not to satisfy condition 2.

2. Synthesis of copolymer used in polycarboxylic acid-based dispersant

(1) Production example 1 (production of copolymer PC-1)

140.1g of ion-exchanged water, 163.0g of α -methacryloyl- ω -methoxy-poly (n ═ 9) oxyethylene, 28.8g of methacrylic acid, 3.8g of 3-mercaptopropionic acid, and 9.9g of a 30% aqueous sodium hydroxide solution were charged into a reaction vessel equipped with a thermometer, a stirrer, a dropping funnel, and a nitrogen gas introduction tube, and dissolved uniformly while stirring, and then the atmosphere was replaced with nitrogen gas, and the temperature of the reaction system was brought to 60 ℃ by a hot water bath. Next, 63.9g of a 3.0% aqueous solution of sodium persulfate was added to start the polymerization reaction. After 2 hours, 28.8g of a 3.0% aqueous solution of sodium persulfate was added and the mixture was held at 60 ℃ for 2 hours, thereby completing the polymerization reaction. To this was added a 30% aqueous sodium hydroxide solution to adjust to pH6, and the concentration was adjusted to 40% with ion-exchanged water. This reaction product was designated as copolymer (PC-1).

(2) Production example 2 (production of copolymer PC-2)

209.2g of ion-exchanged water, 181.9g of α -methacryloyl- ω -methoxy-poly (n ═ 45) oxyethylene, 15.8g of methacrylic acid, and 2.0g of 3-mercaptopropionic acid were charged into a reaction vessel equipped with a thermometer, a stirrer, a dropping funnel, and a nitrogen gas inlet tube, and dissolved uniformly while stirring, and then the atmosphere was replaced with nitrogen gas, and the temperature of the reaction system was brought to 60 ℃ by using a hot water bath. Next, 27.7g of a 1.0% aqueous hydrogen peroxide solution was added dropwise over 2.5 hours. Then, 7.1g of a 1.0% aqueous hydrogen peroxide solution was added dropwise over 3.5 hours to terminate the polymerization reaction. To this was added a 30% aqueous sodium hydroxide solution to adjust to pH6, and the concentration was adjusted to 40% with ion-exchanged water. This reaction product was designated as copolymer (PC-2).

(3) Production example 3 (production of copolymer PC-3)

94.2g of ion-exchanged water was charged into a reaction vessel equipped with a thermometer, a stirrer, a dropping funnel and a nitrogen gas inlet tube, and dissolved uniformly while stirring, and then the atmosphere was replaced with nitrogen gas, and the temperature of the reaction system was brought to 60 ℃ by using a hot water bath. Next, 29.3g of a 1.0% aqueous solution of sodium persulfate was added dropwise over 3.5 hours, and at the same time, an aqueous solution obtained by dissolving 11.7g of methacrylic acid, 183.8g of α -methacryloyl- ω -methoxy-poly (n ═ 113) oxyethylene, and 1.6g of 3-mercaptopropionic acid in 117.3g of ion-exchanged water was added dropwise over 3.0 hours. The reaction mixture was then maintained at 60 ℃ for 2 hours to complete the polymerization. To this was added a 30% aqueous sodium hydroxide solution to adjust to pH6, and the concentration was adjusted to 40% with ion-exchanged water. This reaction product was designated as copolymer (PC-3).

(4) Production example 4 (production of copolymer PC-4)

82.6g of ion-exchanged water and 175.7g of α -methylallyl- ω -hydroxy-poly (n ═ 113) oxyethylene were charged into a reaction vessel equipped with a thermometer, a stirrer, a dropping funnel and a nitrogen gas inlet tube, and dissolved uniformly while stirring, and then the atmosphere was replaced with nitrogen gas, and the temperature of the reaction system was brought to 60 ℃ by using a hot water bath. Then, 9.8g of a 10.0% aqueous hydrogen peroxide solution was added dropwise over 3 hours, and at the same time, an aqueous solution obtained by dissolving 11.7g of acrylic acid and 7.8g of hydroxyethyl acrylate in 97.6g of ion-exchanged water was added dropwise over 3.0 hours, and at the same time, an aqueous solution obtained by dissolving 0.8g of 3-mercaptopropionic acid and 1.0g of ascorbic acid in 7.0g of ion-exchanged water was added dropwise over 4.0 hours. Thereafter, the reaction mixture was held at 60 ℃ for 0.5 hour to terminate the polymerization reaction. To this was added a 30% aqueous sodium hydroxide solution to adjust to pH4, 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)

100.3g of ion-exchanged water and 179.5g of α - (3-methyl-3-butenyl) - ω -hydroxy-poly (n ═ 57) oxyethylene were charged into a reaction vessel equipped with a thermometer, a stirrer, a dropping funnel and a nitrogen gas inlet tube, and dissolved uniformly while stirring, and then the atmosphere was replaced with nitrogen gas, and the temperature of the reaction system was brought to 60 ℃ by using a hot water bath. Next, 9.8g of a 10.0% aqueous solution of sodium persulfate was added dropwise over 3.0 hours, and at the same time, an aqueous solution obtained by dissolving 15.6g of acrylic acid in 78.1g of ion-exchanged water was added dropwise over 3 hours, and at the same time, an aqueous solution obtained by dissolving 1.4g of 3-mercaptopropionic acid and 1.0g of ascorbic acid in 9.4g of ion-exchanged water was added dropwise over 4.0 hours. Thereafter, the reaction mixture was held at 60 ℃ for 0.5 hour to terminate the polymerization reaction. To this was added a 30% aqueous sodium hydroxide solution to adjust to pH4, 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 in accordance with the measurement conditions shown below.

< measurement conditions >

The device comprises the following steps: shodex GPC-101 (Showa electrician)

Column: ohapak SB-806M HQ + SB-806M HQ (Showa electrician)

A detector: differential Refractometer (RI)

Eluent: 0.5mM aqueous sodium nitrate solution

Flow rate: 0.7 mL/min

Column temperature: 40 deg.C

Sample concentration: eluent solution with sample concentration of 0.5 mass%

Standard substance: polyethylene glycol, polyethylene oxide (Agilent)

Water was removed from the copolymers PC-1 to PC-5 produced in production examples 1 to 5, and the solution was adjusted to a concentration of 5% with heavy water and measured by NMR at 300 MHz. This confirmed that each monomer was polymerized to form a copolymer. The types of the 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, the mass (%) of each component, and the values of the mass average molecular weights of the copolymers PC-1 to PC-5 measured as described above are shown in Table 3 below.

[ Table 3]

In the description of table 3, the following terms have the following meanings.

L-1: alpha-methacryloyl-omega-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 -methylallyl- ω -hydroxy-poly (n ═ 113) oxyethylene

L-5: α - (3-methyl-3-butenyl) - ω -hydroxy-poly (n ═ 57) oxyethylene

L-6: acrylic acid hydroxy ethyl ester

M-1: methacrylic acid

M-2: acrylic acid

3. Preparation of polycarboxylic acid-based dispersant

The copolymers PC-1 to PC-5 produced in 2 were each diluted to a concentration of 20% in terms of pH using ion-exchanged water and a 30% aqueous sodium hydroxide solution, and the diluted substances were designated as polycarboxylic acid dispersants SP-1 to SP-12. The copolymers used in the polycarboxylic acid-based dispersant and the pH are summarized and shown in table 4 below.

[ Table 4]

4. Evaluation of compatibility of antifoaming agent with polycarboxylic acid-based dispersant

(1) Test method

5g of the defoamers af-1 to af-9 and af-e1 to af-e3 synthesized in 1 are weighed out separately and mixed with 1000g of the polycarboxylic dispersants SP-1 to SP-12 prepared in 3. Thus, samples (mixed solutions) of examples 1 to 20 and comparative examples 1 to 3 were produced. The types of the polycarboxylic acid-based dispersant and the defoaming agent used in the samples (mixed solutions) of examples 1 to 20 and comparative examples 1 to 3 are summarized in table 5 below. Further, the sample (mixed liquid) was kept in a state of being left standing in a thermostatic chamber until the liquid temperature became 30 ℃. Then, the sample after standing was taken out, sufficiently stirred, and then evaluated for compatibility in a thermostatic chamber at 30 ℃.

(2) Evaluation method and evaluation result of compatibility

Here, the time immediately after completion of the stirring was set to 0 hour (time to start counting), and in examples 1 to 20 and comparative examples 1 to 3, the mixed solution was visually checked for a time t at which the polycarboxylic acid-based dispersant SP-1 and the defoaming agent af-1 were separated from each other every elapsed time of 6 hours, 12 hours, and 24 hours from the time to start counting.

The criteria for evaluation of compatibility are as follows:

a: no separation was confirmed even when the time was more than 24 hours from the start of counting (24 ≦ t)

B: separation was confirmed in a period of 12 hours or more and less than 24 hours (12 ≦ t <24)

C: separation was confirmed in a period of 6 hours or more and less than 12 hours (6 ≦ t <12)

D: less than 6 hours confirmed separation (t <6)

It should be noted that C or more has no problem in actual use. The evaluation results of the compatibility are shown in table 5 below.

[ Table 5]

As is clear from the above, no separation was observed up to 6 hours for the samples of examples 1 to 20 using antifoaming agents af-1 to af-9 satisfying the conditions such as condition 1 and condition 2 of the present invention (evaluation C or more). Namely, the composition shows good compatibility with a polycarboxylic acid dispersant. In particular, regarding antifoaming agents af-1, af-2, af-3, af-4, and af-7 formed by using an unsaturated alcohol a1 (see table 2) having a linear structure with 16 to 18 carbon atoms and a saturated alcohol a2 (see table 2) having a branched structure with 16 carbon atoms, which satisfy the 1 st and 2 nd conditions, no separation was observed in the compatibility between the polycarboxylic acid-based dispersant and the antifoaming agent for "24 hours or more", and they were evaluated as a. That is, it was confirmed that particularly good results were obtained by using unsaturated alcohols having a linear structure or saturated alcohols having a branched structure (examples 1 to 15 and 18).

On the other hand, in the case of the linear structure and the saturated alcohols A3 to a5, the 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, and 20), and the samples were evaluated as B or C, although there was almost no problem in practical use. The above results show that it is significant to use an unsaturated and/or branched primary alcohol having 14 to 22 carbon atoms as the alcohol while satisfying the 1 st and 2 nd conditions of the present invention.

In addition, in the case of the antifoaming agent af-e1 not satisfying the 1 st condition and the antifoaming agent af-e2 not satisfying the 2 nd condition, separation was confirmed in less than 6 hours, and the evaluation was D. This shows that, in the defoaming agent of the present invention, the defoaming agent (polyoxyalkylene compound) represented by the general formula (1) satisfies both the 1 st condition and the 2 nd condition, and is significant in terms of compatibility with the polycarboxylic acid-based dispersant. The antifoaming agent af-e3 did not satisfy condition 1, but the evaluation of compatibility was good (evaluation a). However, since the evaluation of defoaming performance described later is low, it is classified as comparative example 3 here.

5. Effect of defoaming Properties by defoaming agent

Next, the defoaming performance effect of various synthetic defoamers (polyoxyalkylene compounds) such as af-1 was confirmed. First, a concrete composition was prepared as follows.

(1) Preparation of concrete composition

General portland cement (a material obtained by mixing 3 brands of pacific cement, mitsubishi cement, and sumitoo osaka cement, which are equal in weight, and having a specific gravity of 3.16), fine aggregate (dajing chuan water-based sand having a specific gravity of 2.58) and coarse aggregate (crushed stone produced in okada, having a specific gravity of 2.66) as aggregates were sequentially charged into a 55L forced twin-screw mixer at mixing ratios shown in table 6, and after 10 seconds of air mixing, 0.0025 mass% of AE agent "AE-300 (trade name, bamboo oil and fat)" with respect to cement, polycarboxylic acid-based dispersants SP-1, SP-3, and SP-12 shown in table 4, antifoaming agents af-1 to af-9 shown in table 2, and af-e3 shown in table 8 were added together with water in such amounts as to adjust the amounts, kneading was then carried out for 90 seconds. Here, the antifoaming agent af-1 and the polycarboxylic acid-based dispersant SP-1 are considered to be part of the kneading water. In addition, the polycarboxylic acid dispersants SP-5 and SP-9 shown in Table 4 and the antifoaming agents af-1 to af-9 and af-e3 shown in Table 2 were kneaded at the mixing ratios shown in Table 7 in the same manner, and the types shown in Table 9 below were used.

[ Table 6]

[ Table 7]

(2) Effect of defoaming Properties

The concrete composition immediately after kneading was measured for "air amount (%)" in accordance with JIS-A1128. The air amount (%) represents the volume% in the hydraulic composition. In addition, the air amount (%) was measured, and the slump (cm) was measured in accordance with JIS-A1101. From these air amounts (%), the effect of defoaming performance of the defoaming agent was confirmed. The measurement results of the air amount (%) and the slump (cm) are shown in tables 8 and 9 below.

[ Table 8]

[ Table 9]

As can be seen from the above, the defoaming agents af-1 to af-9 satisfying the 1 st and 2 nd conditions of the present invention all exhibited good defoaming performance (examples 21 to 44). On the other hand, it was confirmed that when the antifoaming agent af-e3 synthesized for comparison was used, the antifoaming effect was significantly reduced as compared with af-1 to af-9 (comparative examples 4 to 8). In af-e3, even if the amount of polycarboxylic acid dispersant added (mass%/dispersant) exceeds 1.00, the air amount (%) shows 10% or more, and therefore, addition of the amount or more is not performed. That is, it was confirmed that when the defoaming agent of the present invention is used as an essential component of a hydraulic composition, high defoaming performance can be exhibited even with a small amount of the addition of the defoaming agent in addition to the compatibility described above.

Industrial applicability

The antifoaming agent for a hydraulic composition according to the present invention is useful as an antifoaming agent in the production of a hydraulic composition. Furthermore, the additive for hydraulic compositions according to the present invention can be used as an additive in the production of hydraulic compositions. The hydraulic composition of the present invention is excellent in compatibility with a dispersant, and can be advantageously used in various buildings and building parts by using a defoaming agent which exhibits high defoaming performance when added in a small amount.

Claims

1. An antifoaming agent for a hydraulic composition, which is a polyoxyalkylene-based compound represented by the following general formula (1) and satisfies the following relationship:

condition 1: 0.16 ≦ n/(p + n + m) ≦ 0.40, and

condition 2: 20 < p + n + m < 48,

RO-(AO)p-(EO)n-(AO)m-H···(1)，

wherein R represents an alkyl group or an alkenyl group having 8 to 30 carbon atoms, and represents any one of a linear chain and a branched chain; AO represents the same or different oxyalkylene group having 3 to 18 carbon atoms; EO represents an oxyethylene group; p, n and m each represent an average molar number of addition, and p is 0 or more, n is 1 or more and m is 1 or more.

2. The antifoaming agent for hydraulic compositions according to claim 1, characterized in that,

in the general formula (1), R is alkyl or alkenyl with 14-22 carbon atoms, and

the hydroxyl group-removed residue is contained in an amount of 50 mass% or more based on the total amount of R.

3. The antifoaming agent according to claim 1 or 2, wherein AO in the general formula (1) is an oxypropylene group.

4. The antifoaming agent according to any one of claims 1 to 3, wherein the condition 1 further satisfies a condition of 0.16 ≦ n/(p + n + m) ≦ 0.38.

5. The antifoaming agent according to any one of claims 1 to 4, wherein the condition 2 further satisfies the condition of 24 ≦ p + n + m ≦ 40.

6. The antifoaming agent according to any one of claims 1 to 5, wherein R in the general formula (1) has 14 to 22 carbon atoms.

7. An additive for hydraulic compositions, which comprises the antifoaming agent for hydraulic compositions according to any one of claims 1 to 6, a polycarboxylic acid-based dispersant, and water as essential components.

8. A hydraulic composition comprising the antifoaming agent for a hydraulic composition according to any one of claims 1 to 6, a polycarboxylic acid-based dispersant, and cement as essential components.

9. A hydraulic composition comprising the antifoaming agent for a hydraulic composition according to any one of claims 1 to 6, a polycarboxylic acid-based dispersant, cement, and aggregate containing fine aggregate and/or coarse aggregate as essential components.