JPH08196811A - Production of oil compound for antifoaming agent and antifoaming agent composition containing the same - Google Patents

Abstract

PURPOSE: To obtain such an oil compound for an antifoaming agent that can be economically and safely produced and that the obtd. produce shows good dispersibility and low viscosity, and to obtain an antifoaming compsn. which contains this compd. and has high holding property of the antifoaming effect and improved dilution stability. CONSTITUTION: This oil compd. is produced by mixing three components of (1) 100 pts.wt. straight-chain or branched-chain hydrophobic organopolysiloxane having 10 to 5×10<6> cSt viscosity at 25 deg.C, (2) 0.1 to 30 pts.wt. fine powder silica having >=100m<2> /g BET specific surface area, and (3) 0.01 to 1 pt.wt. dispersion improving agent comprising an inorg. or org. acid while heat treating the mixture at 60-300 deg.C.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an antifoaming oil compound and an antifoaming composition containing the same.

[0002]

2. Description of the Related Art Since silicone type antifoaming agents have various excellent properties as compared with other defoaming agents, production involving foaming in chemical industry, food industry, petroleum industry, textile industry, pharmaceutical industry, etc. It is widely used in the process. For this, an oil compound type defoaming agent in which silicone oil such as dimethylpolysiloxane, methylphenylpolysiloxane, and methylvinylpolysiloxane is mixed with fine powder silica, and these oil compounds are used as surfactants. Along with this, emulsion type defoaming agents dispersed in water are widely used. Also, this emulsion type defoaming agent is destructive of the defoaming ability by breaking the emulsion under severe conditions such as high temperature, high alkalinity and high shearing force. Self-emulsifying defoaming agent that uses polysiloxane and oil compound in combination (Japanese Patent Publication No. 52-19836, Japanese Patent Publication No. 52-22638,
Japanese Patent Publication No. 55-23084) is used for dyeing, various oils, and water-based inks.

[0003]

However, these silicone type defoaming agents also defoam in a system which is violently contacted with a gas in a foaming liquid or which is vigorously stirred under heating conditions such as high temperature dyeing. However, there is a problem in that it is necessary to increase the amount of the defoaming agent added or to continuously add the defoaming agent because the amount is lost over time. Therefore, as for this silicone-based defoaming agent, for example, silica used in an oil compound is previously treated with dimethyldichlorosilane or the like to be hydrophobized (see Japanese Patent Publication No. 52-31836), and silica is used as a nitrogen-containing organic silicon. A method of treating with a compound (see Japanese Patent Publication No. 51-35556) has been proposed, but these methods require a long time for the hydrophobic treatment of silica, require a treatment facility, and are complicated in the process. It was not the target. Further, an organohydrogenpolysiloxane or a hydrocarbon compound to which an organohydrogenpolysiloxane, silica and a catalyst are added has also been proposed (see JP-A-57-48307), which is an organometallic catalyst. The surface treatment of silica does not proceed sufficiently without adding and heat treatment, and there is a risk of ignition and explosion due to hydrogen gas generated during the treatment process.Additionally, organosilicon compounds and catalysts are added to organopolysiloxane and silica. And heat treatment (see Japanese Patent Publication No. 3-39722) in which a siloxane resin composed of (CH ₃ ) ₃ SiO _1/2 units and SiO _4/2 units is blended with organopolysiloxane and silica (see Fairness 3-129
No. 23), and a method of treating silica with a mixture of a cyclic siloxane, water and a reaction accelerator (Japanese Patent Laid-Open No. 6-54545).
However, these have the disadvantage that the defoaming sustaining effect is not always satisfactory.

Therefore, the present inventors have previously mentioned a method in which an inorganic ammonium salt compound is mixed with organopolysiloxane and hydrophobized silica for the purpose of improving the defoaming durability under high temperature and high shearing force, followed by heat treatment. (See Japanese Patent Publication No. 4-42043), an oil compound component composed of a silicone oil having a branching unit and silica (see Japanese Laid-Open Patent Publication No. 6-12411) is proposed, and according to these, the defoaming sustainability is improved. Although an excellent defoaming agent composition can be obtained, there is a demand for an antifoaming agent composition having a low cost and a high durability.

[0005]

The present invention relates to a method for producing an oil compound for an antifoaming agent, which solves the problems of the above conventional antifoaming agents, and (b) the line represented by the general formula (1). Hydrophobic organopolysiloxane R ¹ _a SiO _{(4-a) / 2} (1) with _a viscosity of 10 to 500,000 cSt at 25 ° C, which is branched or branched, (R ¹ is a hydroxyl group or monovalent carbon having 1 to 18 carbon atoms One or more monovalent organic groups selected from hydrogen groups, 1.9 ≦ a ≦ 2.4) 100 parts by weight (b) 0.1-30 parts by weight of finely divided silica having a specific surface area of 100 m ² / g or more by the BET method (C) Dispersion improver comprising inorganic acid or organic acid 0.01 to 1 part by weight of three components are mixed and heat-treated at 60 to 300 ° C. in a method for producing an oil compound for an antifoaming agent. is there. At the same time, the present invention also relates to various defoamer compositions containing the oil compound for defoamers obtained by these production methods.

That is, the present inventors have conducted various studies on the method for producing an oil compound to be used in order to develop an antifoaming composition having excellent antifoaming properties and defoaming sustainability. When a stirring and heat treatment is performed by adding a dispersibility improver composed of an inorganic acid or an organic acid to a composition composed of a crystalline organopolysiloxane and finely divided silica, the wettability of the finely divided silica to the organopolysiloxane is improved, It has been discovered that an oil compound for antifoaming agents can be obtained which forms a good dispersed state and therefore maintains the defoaming property even under vigorous stirring. Furthermore, when an emulsion type defoaming agent composition, a self-emulsifying type defoaming agent composition, etc. were produced using this defoamer oil compound as a raw material, it was confirmed that the defoaming durability and the dilution stability were excellent. The present invention was completed.

In order to produce this defoamer oil compound, expensive hydrophobized silica and special production equipment are not required, and it can be easily obtained by simple mixing and heat treatment of the above-mentioned components, which is economical and economical. It's safe. Further, the obtained antifoaming agent oil compound has a low viscosity because of good dispersibility, and it has been confirmed that workability is improved.

The present invention will be described in more detail below. The hydrophobic organopolysiloxane as the component (a) in the production of the oil compound for a defoaming agent of the present invention may be linear or branched as long as it is represented by the general formula (1). good.

R ¹ in the general formula (1) is a hydroxyl group or methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, dodecyl group, tetradecyl group. , Alkyl groups such as hexadecyl group and octadecyl group; cycloalkyl groups such as cyclohexyl group; alkenyl groups such as vinyl group and allyl group; aryl groups such as phenyl group and tolyl group; 2-phenylethyl group, 2-methyl-2 -A chloromethyl group such as a phenylethyl group or a chloromethyl group in which a part or all of hydrogen atoms bonded to carbon atoms of these groups are substituted with a halogen atom, a cyano group, an amino group, a 3-chloropropyl group, 3,3,3-trifluoropropyl group, cyanoethyl group, 3-aminopropyl group, N-β- (amido A monovalent organic group having 1 to 18 carbon atoms selected from, ethyl)-.gamma.-aminopropyl group, is preferably more than the 80 mol% from the defoaming and economy is a methyl group. Further, a in this equation is expressed by 1.9 ≦ a ≦ 2.4. It should be noted that this may be liquid at room temperature, but 25
The viscosity at 0 ° C must be 10 to 500,000 cSt, preferably 50 to 20,000 cSt. Generally, a high viscosity is preferable to maintain the defoaming property, and a low viscosity is preferable from the viewpoint of fast-acting property, but if the viscosity is less than 10 cSt, it easily dissolves in the foaming system and the defoaming property is improved. Is inferior and the viscosity is 50
This is because if it exceeds 0,000 cSt, the workability during production or use of the oil compound deteriorates. The value of a is correlated with the viscosity and the structure of the hydrophobic organopolysiloxane used, and assuming that the hydrophobic organopolysiloxane used is linear, the value of a is about 2.4 at a viscosity of 10 cSt and the viscosity is 500,000. When the hydrophobic organopolysiloxane used is branched, the value of a decreases as the number of branching units increases, but considering the range that can actually be used for oil compounds, the viscosity is 500,
At 000 cSt, the value of a is almost 1.9. Thus, the range of the value of a is limited by the viscosity and the structure of the organopolysiloxane.

The finely divided silica as the component (b) may be a known one, which may be either wet silica or dry silica. Examples thereof include precipitated silica, silica xerogel, fumed silica, and those whose surface is treated with an organic silyl group. Specifically, Aerosil [trade name of Nippon Aerosil Co., Ltd.], Nipseal [Nippon Silica Co., Ltd. ) Product name], Cabosil [product name manufactured by US Cabot Corporation], Santocell [product name manufactured by Monsanto Company], etc., and these have a specific surface area of 100 m ² by the BET method.
/ g or more, preferably 200
m ² / g or more. This is because the larger the value, the better the defoaming property. The amount of the finely divided silica added was 100 parts by weight of the above-mentioned hydrophobic organopolysiloxane.
If the amount is less than 0.1 parts by weight, the defoaming ability is poor, and if the amount is more than 30 parts by weight, the viscosity of the composition increases and the water dispersibility and workability deteriorate, so it is necessary to set the amount to 0.1 to 30 parts by weight, preferably 1 to 15 parts by weight.

As the dispersibility-improving agent of the component (c), usual inorganic acids or organic acids can be used. For example, inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, formic acid, acetic acid,
Organic acids such as trifluoroacetic acid and benzoic acid can be exemplified, but hydrochloric acid and sulfuric acid are particularly preferable because they have relatively little odor and discoloration. If the amount of these dispersibility improvers added is less than 0.01 parts by weight with respect to 100 parts by weight of the above-mentioned hydrophobic organopolysiloxane, the effect of improving dispersibility is insufficient, and even if it is more than 1 part by weight, the effect is improved. When using the defoaming agent composition obtained instead, the residual acid component may adversely affect corrosion and the like.
01 to 1 part by weight is suitable, and preferably 0.02 to 0.2 part by weight. In addition, since the amount of the dispersibility improver added to obtain the desired effect is very small, the dispersibility improver may be added with water or the like from the viewpoint of controlling the added amount and safety. It is preferable to add it after diluting it to a concentration of 20%.

In producing the defoamer oil compound of the present invention, 60 to 60% of the above-mentioned components (a), (b) and (c) are mixed in a mixer having an appropriate stirring mechanism. 300 ° C for 1-8 hours, more preferably 100-180
It is necessary to perform heat treatment at 2 ° C. for 2 to 5 hours, and according to this method, it is possible to obtain a homogeneous defoamer oil compound having a viscosity of several tens to several millions cSt. The reason for limiting to the above heating conditions is that in the production of an oil compound for an antifoaming agent, it is necessary to mix the two under heating conditions in order to chemically adsorb the oil, that is, the organopolysiloxane on the surface of silica. The defoaming property is exhibited. In order to further improve the defoaming property, it is preferable to mix the organopolysiloxane at a temperature as high as the thermal decomposition temperature for a long time, but if it is less than 1 hour, the defoaming property is insufficiently improved. But the effect does not change. The thermal decomposition temperature of the organopolysiloxane used, the conditions of the manufacturing process,
Considering the economic efficiency, etc., at 60-300 ℃ for 1-8 hours,
More preferably, the condition of heating at 100 to 180 ° C. for 2 to 5 hours was set.

The oil compound for a defoaming agent of the present invention thus obtained may be added to the foaming system as it is, but it is a self-emulsifying type obtained by mixing it with an emulsifier component containing a polyoxyalkylene-modified silicone oil as a main component. By using as a defoaming agent composition, further high temperature, high alkali,
It is possible to improve the defoaming durability under high shearing force. Further, depending on the purpose and application, it may be used as an emulsion type defoaming agent composition emulsified with an appropriate surfactant.

Examples of the surfactant used include sorbitan fatty acid ester, glycerin fatty acid ester, propylene glycol fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkyl ether and polyoxyalkylene polymer. However, it is not limited to those listed here. Further, for this emulsion type antifoaming agent, a protective colloid agent at the time of emulsification, a thickening agent, a stability improving agent and the like, cellulose ether such as methyl cellulose, carboxymethyl cellulose and carboxyethyl cellulose, polyvinyl alcohol, sodium alginate, Sugar fatty acid ester, sodium polyacrylate, etc. may be added, and sodium hypochlorite, sorbic acid, potassium sorbate, as an antiseptic agent,
A bactericide such as salicylic acid, benzoic acid, alkyl paraoxybenzoates, and organic nitrogen-sulfur compounds may be added.

Further, the oil compound for a defoaming agent of the present invention is a solution type defoaming agent dissolved or dispersed in an organic solvent such as an aliphatic hydrocarbon solvent, an aromatic hydrocarbon solvent, an ether solvent, an alcohol solvent or the like. It may be used as a composition, or a powder type defoaming agent composition adsorbed to a fine powder carrier such as methyl cellulose, polyvinyl alcohol, lactose, dextrin, hydrophilic fine powder silica, starch or a solid surfactant at room temperature. It is also possible to use it as a solid type defoaming agent composition prepared by blending a water-soluble wax and the like. The appropriate addition amount of the above various defoaming agent compositions to the foaming system varies depending on the type of the foaming system and the use conditions, but is 1 to 1 in terms of the oil compound component contained in the defoaming agent composition except for special cases. A range of several hundred ppm is preferable.

[0016]

EXAMPLES Examples and comparative examples of the present invention will be given below.
The viscosity here indicates a measured value at 25 ° C.
Various physical property values were measured according to the following methods.

(Defoaming durability test 1) In 100 g of an oil compound for an antifoaming agent, the average composition formula was R ² _0.1 (CH ₃ ) _2.0 SiO
_{^{0.95 [R 2 = -C 3 H}} 6 O (C 2 H 4 O) 25 (C 3 H 6 O) 25 C 4 H 9] represented by the viscosity of the addition of polyoxyalkylene-modified silicone oil 150g of 1,400cSt Then, the mixture was uniformly mixed with a homomixer at room temperature to prepare a self-emulsifying antifoam composition. Next, in a 150 ml glass bottle with a stopper, 50 g of a 1% aqueous solution of polyoxyethylene sorbitan monooleate / Leodol Super TW-O 120 [trade name of Kao Corporation] is placed, and the above self-emulsifying defoamer composition is added thereto. 100 μl of 10% aqueous dispersion of was added and set on a shaker. Immediately after adding this, 2 hours, 5 hours, 10 hours, and 24 hours later, 250 times /
After shaking for 1 minute × 1 minute, the time (seconds) required for defoaming was measured.

(Dilution Stability Test 1) Defoaming Sustainability Test 1
10% aqueous dispersion of self-emulsifying defoamer composition prepared in
After being placed in a 300 ml beaker and left at 25 ° C. for 1 day, the appearance of the liquid was visually observed and evaluated according to the following criteria. ◯: Good emulsion with no oil floating and no silica precipitation. Δ: There is some oil floating or silica sedimentation. ×: A lot of oil floats and a lot of silica sedimentation.

(Antifoaming persistence test 2) 20 g of oil compound for antifoaming agent, 20 g of sorbitan monostearate nonion SP-60R [trade name of NOF CORPORATION], polyoxyethylene cetyl ether nikkor BC- 30T
20g of X [trade name of Nikko Chemicals Co., Ltd.] and 20g of polypropylene glycol Uniol D-4000 [trade name of NOF CORPORATION] are heated and mixed at 60 to 70 ° C, after which 840g of water is gradually added. While in a homomixer 20
The mixture was stirred for a minute and emulsified to prepare an emulsion type antifoam composition. Then in a graduated cylinder with an internal volume of 1 liter
Take 100 g of 0.2% sodium oleate aqueous solution, and add 10% water dilution of the above emulsion type antifoam composition.
Add 1.5g, air bubbling at 1 liter / min through glass diffuser stone,
Foaming amount after 5, 10, 15 and 20 minutes [(total amount of (foaming amount + liquid amount) m
l] was measured.

(Dilution Stability Test 2) Defoaming Sustainability Test 2
10% water dilution of the emulsion type antifoam composition prepared in
100 g was placed in a 300 ml beaker, and the liquid appearance after standing for 1 day at 25 ° C. was visually observed and evaluated according to the following criteria. ◯: Good emulsion with no oil floating and no silica precipitation. Δ: There is some oil floating or silica sedimentation. ×: A lot of oil floats and a lot of silica sedimentation.

Example 1 Dimethylpolysiloxane KF-96 [trade name of Shin-Etsu Chemical Co., Ltd.] having a viscosity of 100 cSt as the hydrophobic organopolysiloxane of component (a) 100
Part by weight, (b) component fine powder silica nip seal HD
-2 [Nippon Silica Co., Ltd. product name, specific surface area 300 m ² /
g] 10 parts by weight, 2N-as a dispersibility improving agent for the component (c)
When 0.5 part by weight of hydrochloric acid (hydrochloric acid content: 0.037 part by weight) was mixed in a nitrogen gas stream at 150 ° C for 3 hours, the viscosity was increased.
An oil compound A of 300 cSt was prepared.

(Example 2) KF-96 [trade name of Shin-Etsu Chemical Co., Ltd.] having a viscosity of 1,000 cSt as the hydrophobic organopolysiloxane of component (a) 1
The same procedure as in Example 1 was carried out except that 00 parts by weight was used.
An oil compound B having a viscosity of 2,200 cSt was prepared.

(Example 3) 100 parts by weight of methylphenylpolysiloxane KF-50 [trade name of Shin-Etsu Chemical Co., Ltd.] having a viscosity of 300 cSt as the hydrophobic organopolysiloxane of component (a), component (b) Fine powder silica nip seal L-300 [product name of Nihon Silica Co., Ltd., specific surface area 2
Oil compound C having a viscosity of 1,200 cSt was prepared in the same manner as in Example 1 except that 12 parts by weight of 00 m ² / g] was used.

(Example 4) The same treatment as in Example 1 was carried out except that 0.5 part by weight of 2N-sulfuric acid (sulfuric acid content: 0.049 part by weight) was used as a dispersibility improving agent for the component (c), and the viscosity was changed. An oil compound D of 330 cSt was prepared.

(Examples 5 and 6) 1N-hydrochloric acid 0.6 part by weight (hydrochloric acid content: 0.022 part by weight) or 4N-hydrochloric acid 1 part by weight (hydrochloric acid content: 0.146)
(Part by weight) was treated as in Example 1 except that
Oil compounds E and F having viscosities of 420 cSt and 280 cSt were prepared.

(Comparative Example 1) An oil compound G having a viscosity of 800 cSt was prepared in the same manner as in Example 1 except that the dispersibility improver as the component (c) was not used. (Comparative Example 2) 0.2N-as a dispersibility improving agent for the component (C)
An oil compound H having a viscosity of 1,200 cSt was prepared in the same manner as in Example 1 except that 0.5 part by weight of hydrochloric acid (hydrochloric acid content: 0.0037 parts by weight) was used.

Comparative Example 3 The same treatment as in Example 1 was carried out except that 0.1 part by weight of potassium hydroxide was used instead of the dispersibility improving agent of the component (c), and then neutralized with phosphoric acid to obtain a viscosity. But
An oil compound I of 2,200 cSt was prepared. (Comparative Example 4) Instead of the dispersibility improver of the component (C) (C
H ₃₎ consists ₃ SiO _1/2 units and SiO _{4/2 units, (CH 3) 3 SiO 1/2} /
The same procedure as in Example 1 is repeated except that 1 part by weight of a siloxane resin having a SiO _4/2 molar ratio of 0.85 is used.
An oil compound J of St was prepared.

(Comparative Example 5) Surface-hydrophobized silica Aerosil 200 [tradename of Nippon Aerosil Co., Ltd., specific surface area 200 m ² / g] as (CH ₃ ) ₃ was used as fine powder silica of (b) component.
Use 10 parts by weight of SiNHSi (CH ₃ ) ₃ treated (C)
Example 1 except that no dispersibility improver for the components was used
An oil compound K having a viscosity of 1,100 cSt was prepared in the same manner as above.

Comparative Example 6 Hexamethylcyclotrisiloxane 100 parts by weight, isopropanol 100 parts by weight, water 35
After mixing a mixture of 50 parts by weight and 0.05 parts by weight of sodium hydroxide at 50 ° C. for 30 minutes, 10 parts by weight of finely powdered silica Nipseal HD-2 [previously described] was added and further mixed at 50 ° C. for 5 minutes.
Mixed for hours. Then, after neutralizing with phosphoric acid, the low boiling point components of this product are heated at 150 ° C for 1 hour to be removed, and the viscosity is 12
An oil compound L of 0 cSt was prepared. Defoamer oil compound A obtained as described above
When the defoaming durability and the dilution stability of L were examined, Table 1
The result as shown in was obtained.

[0030]

[Table 1]

[0031]

INDUSTRIAL APPLICABILITY To produce this antifoaming agent oil compound, expensive hydrophobized silica and special production equipment are not required, and it is easily obtained by simple mixing and heat treatment of the above-mentioned components, and therefore, it is economical. And safe. Further, the obtained oil compound for antifoaming agent has low viscosity because of good dispersibility, and it has been confirmed that workability is improved. In addition, the antifoam composition containing the same provides high defoaming durability and improved dilution stability at low cost.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Atsushi Matsuzaka 1 Hitomi, Osamu Matsuida-cho, Usui-gun, Gunma Prefecture Inside the Silicon Electronic Materials Research Laboratory, Shin-Etsu Chemical Co., Ltd. (72) Satoshi Kuwata Matsuida-cho, Usui-gun, Gunma Prefecture Hitomi, Daiji 10 Shin-Etsu Chemical Co., Ltd. Silicon Electronic Materials Research Laboratory

Claims (2)

[Claims] 1. (a) A hydrophobic or organopolysiloxane R ¹ _a SiO _{(4-a) / 2 having a} linear or branched viscosity of 10 to 500,000 cSt at 25 ° C., represented by the general formula (1). (1) (R ¹ is one or more monovalent organic groups selected from a hydroxyl group or a monovalent hydrocarbon group having 1 to 18 carbon atoms, and 1.9 ≦ a ≦ 2.4) 100 parts by weight (B) BET Fine powder silica with a specific surface area of 100 m ² / g or more by the method 0.1 to 30 parts by weight (c) Dispersion improver consisting of an inorganic or organic acid 0.01 to 1 part by weight While mixing three components of 60 to 300 ° C A method for producing an oil compound for an antifoaming agent, which comprises heat-treating at. 2. A defoaming composition containing the oil compound for a defoaming agent obtained in claim 1.