JPH0130528B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a silicone antifoaming agent, particularly a self-emulsifying silicone antifoaming agent that effectively suppresses foaming in a high temperature, strongly acidic or strongly alkaline aqueous system. Silicone antifoaming agents, especially antifoaming agents whose main component is dimethylpolysiloxane, have various superior properties compared to other types of antifoaming agents, so they are used in the chemical industry, food industry, petroleum industry, textile industry, etc. It is widely used as a treatment agent for unwanted foam in industrial and pharmaceutical industries. Since the main component of this silicone antifoaming agent, dimethylpolysiloxane, is essentially hydrophobic, it is practically used as an emulsion in which it is dispersed in water together with a surfactant. If the liquid to be treated is at a high temperature, or is strongly acidic or alkaline, the emulsion will be destroyed, making it impossible to expect the desired foaming suppression effect, and in some cases promoting foaming. This dimethylpolysiloxane has the disadvantage of being separated from the emulsion and losing its antifoaming effect when shearing force is applied or when it is stored for a long period of time. Therefore, silicone antifoaming agents that use organopolysiloxane modified with polyoxyalkylene groups as a main ingredient instead of dimethylpolysiloxane have been proposed (Japanese Unexamined Patent Application Publication No. 1973-1993).
(Refer to Publication No. 10188), this is applied to defoaming the dyeing solution during high-temperature dyeing. The foaming effect is extremely poor, and since the foaming effect is not achieved unless the temperature is above the clouding point, there is a drawback that the foaming effect is poor at low temperatures around room temperature. The present invention relates to a silicone antifoaming agent which solves these disadvantages, and which has the general formula [Here, R ¹ is a hydrogen atom or 1 having 1 to 10 carbon atoms.
A valent hydrocarbon group, G is a formula -R ³ _d O _e - (C ₂ H ₄ -) _f - (R ² O-) _g A (where A is a hydrogen atom, a monovalent hydrocarbon having 1 to 10 carbon atoms) group, acyl group or isocyanate group, R ² is a divalent hydrocarbon group having 3 to 10 carbon atoms, R ³ is a carbon number 2
~10 divalent hydrocarbon groups, d and e are each 0 or 1, f and g are positive integers of 1 or more), and X is a general formula -R ⁴ NH ₂ (where R ⁴ is a divalent hydrocarbon group having 2 to 10 carbon atoms) or general formula

【formula】

[Formula] (where R ⁵ is a divalent hydrocarbon group having 2 to 10 carbon atoms,
Z is a group having 2 to 10 carbon atoms and containing at least one primary or secondary amino group bonded to an adjacent carbon atom;
a, b, and c are each 0, 1, 2, or 3, a+b+c=3, m and n are each a positive integer of 1 or more, and l is 0 or
100 or less] and contains an oxyalkylene group and an amino group-containing organic group in its molecule as a main ingredient. To explain this, the present inventors have conducted various studies on antifoaming agents that exhibit excellent foaming inhibiting properties even in aqueous systems such as high temperatures, strong acidity, and strong alkalinity. It was discovered that organosiloxanes contained simultaneously in the same molecule exhibited such properties, and as a result of further research, it was found that this type of organopolysiloxane has excellent water solubility even if the modification rate of polyoxyalkylene is low. In addition, antifoaming agents based on this material have a higher antifoaming effect than conventionally known polyoxyalkylene-modified polysiloxanes, and can achieve the same effect with 1/2 to 1/4 the amount used as conventional products. We completed the present invention by confirming that when this dye is used for high-temperature dyeing, it eliminates tarring, so oil spots that appear on the surface of fabrics and threads during dyeing can be easily washed away with water. . The organopolysiloxane as the main ingredient constituting the antifoaming agent of the present invention is represented by the above-mentioned general formula (), in which R ¹ is a methyl group,
Alkyl groups such as ethyl, propyl and butyl groups, cycloalkyl groups such as cyclohexyl and cyclopentyl groups, alkenyl groups such as vinyl and allyl groups, aryl groups such as phenyl and tolyl groups, and aralkyl groups such as benzyl groups. , or a monovalent hydrocarbon group having 1 to 10 carbon atoms, such as a group in which the hydrogen group bonded to the carbon atom of these groups is partially substituted with a halogen atom. More than 50% is said to be a methyl group. G in this formula () is an oxyalkylene group represented by the formula -R ³ _d O _e - (C ₂ H ₄ O-) _f - (R ² O-) _g A ... (), and this formula ^R2 is a divalent hydrocarbon group having 3 to 10 carbon atoms such as propylene group, isopropylene group, butylene group, isobutylene group, and ^R3 is a carbon group such as ethylene group, propylene group, butylene group, isobutylene group, etc. A number of 2 to 10 divalent hydrocarbon groups, and A is a group selected from a hydrogen atom, an alkyl group, an acyl group, or an isocyanate group, exemplified by a methyl group, an ethyl group, a propyl group, an acetyl group, a propionyl group, etc. d and e are each 0 or 1, and f and g are positive integers of 1 or more. Examples of G include the following. (However, 0≦p, 0≦q, 1≦p+q) Also, X in this formula () is the formula -R ⁴ NH ₂ ... (), is selected from the groups represented by
R ⁴ and R ⁵ are both ethylene group, propylene group,
A divalent hydrocarbon group having 2 to 10 carbon atoms, exemplified by an alkylene group such as a butylene group, an arylene group such as a phenylene group, and an alkaline group such as a phenethylene group, where Z is a 1 bonded to the adjacent carbon atom through a nitrogen atom. A primary amino group with one active hydrogen or a secondary amino group with no active hydrogen (-C-NH- or -C
-N=) containing at least one carbon number 1 to 10
This is a valent group, and examples of this X include the groups shown below. Therefore, the organopolysiloxane represented by the above formula () that simultaneously contains both the oxyalkylene group (G) shown above and the amino group-containing organic group (X) in the same molecule is as follows: The number of siloxane groups in the organopolysiloxane (m+
The ratio m+2b/m+n+l+2 of the number of oxyalkylene groups (m+2b) to n+l+2) is 0.01 to
0.3, or the ratio n+ to the number of amino group-containing organic groups
2c/m+n+l+2 is 0.01 to 0.4, and the ratio to the number of dialkyl group-bonded siloxane groups is l/m+n+l.
It is preferable that +2 is in the range of 0.3 to 0.92.
In this case, the ratio m+2b/n+2c of the number of oxyalkylene groups to the number of organic groups containing amino groups does not need to be particularly limited and is arbitrary, but the total number of siloxane groups (m+n+l+2)
is preferably in the range of 5 to 200. This organopolysiloxane represented by the above general formula () can be produced by various methods, but
An organopolysiloxane containing an aminoalkyl group represented by the above formula () can be prepared by, for example, combining a polyoxyalkylene compound containing an unsaturated bonded organic group in the molecule and an amino compound simultaneously or separately in the presence of a platinum-based catalyst. Polyoxy which is subjected to an addition reaction with a hydrogen atom-containing organopolysiloxane or is a hydrolyzed condensate of cyclosiloxane or dihalosilane that simultaneously contains an alkyl group and an amino group-containing organic group in the molecule, and a polyoxy whose terminal end is capped with a triorganosilyl group. It can be obtained by equilibrating an alkylene group-containing polysiloxane and a dialkylcyclosiloxane in the presence of an acidic catalyst such as sulfuric acid or a basic catalyst such as potassium hydroxide, and is obtained by the above formulas (), (). The organopolysiloxane represented by the above general formula () containing groups represented by , () is ≡Si-R ⁶ (where R ⁶ is

【formula】

[Formula] Also teeth

It can be synthesized by adding an amino compound to a polyoxyalkylene epoxy polysiloxane having a bond represented by the formula: In addition, this oxyalkylene group-containing polysiloxane having ≡Si-R ⁶ bonds can be obtained by a conventionally well-known method, for example, by combining a polyoxyalkylene compound containing an unsaturated bonded organic group in the molecule with allyl glycidyl ether or glycidyl alcohol. , 1,4-cyclohexane diene monooxide, etc., to a hydrogen atom-containing polysiloxane in the presence of a platinum-based catalyst. If an amine compound is reacted with an oxyalkylene epoxy polysiloxane, an organopolysiloxane represented by the general formula () can be obtained. Examples of the amine compound include triethylenetetramine, ethylenediamine, cyclohexylamine, allylamine, monoethanolamine, Primary amines such as methylbenzylamine, dimethylamine, dibutylamine,
Examples include secondary amines such as morpholine, piperidine, and diethanolamine. The antifoaming agent of the present invention is mainly composed of a diorganopolysiloxane containing a polyoxyalkylene group and an amino group-containing organic group obtained as described above. It is used dissolved or dispersed in water, but it can also be emulsionized in the presence of emulsifiers such as oxyalkylene compounds, sorbitan fatty acid esters, higher alcohol ethers, sodium lauryl sulfonate, etc. It may be hot. The antifoaming agent of the present invention thus obtained exhibits excellent antifoaming and foam-breaking properties, and it does not lose its antifoaming properties even in high-temperature, strong acid, or strongly basic aqueous systems. It can be widely used in a variety of fields because it has no silicone, but it also has stable water dispersibility, so like general silicone emulsions, it can impart mold releasability or lubricity to processed objects. It can also be suitably used for this purpose. Next, reference examples and examples of the present invention will be given, and the viscosity and refractive index in the examples are both measured values at 25°C. Reference example 1 The following formula in the reactor Methylhydrodiene polysiloxane represented by
234g (0.1 mol) and the following formula (P = q, average 2000) A polyoxyalkylene compound and allylglycidyl ether represented by the formula (p = q, average 2000) were charged in an amount such that the total amount thereof was 0.33 mol, and to this was added 770 mol of toluene.
g and 0.2 g of a 2% alcoholic solution of chloroplatinic acid were added, and the reaction was carried out under heating and reflux at approximately 120°C for 8 hours. Then, ethylenediamine in an amount 4 times the molar amount of allyl glycidyl ether mentioned above was added to give 70 g. The mixture was heated and reacted at ℃ for 2 hours. Next, this reaction product was heated at 120°C under a pressure of 10mmHg.
When the volatile fraction was distilled off by heating to .degree. C., a polyoxyalkylene aminopolysiloxane corresponding to the following formula was obtained. (Here Note that Equation _G1 indicates the case where e=0 in Equation G described in the claims. By changing the amounts of the polyoxyalkylene compound and ethylenediamine added above, polyoxyalkylene aminopolysiloxanes with different values of m ₁ and n ₁ in the above formula were made, and their physical properties were measured. The results shown in the table were obtained.

[Table] Reference Example 2 The polyoxyalkylene compound used in Reference Example 1 is expressed by the following formula: (p = q, average molecular weight 2500) The same procedure as Reference Example 1 was carried out except that morpholine was used instead of ethylenediamine, and the polyoxyalkylene amino polysiloxane represented by the following formula was obtained. Obtained. however Regarding this, we also created polyoxyalkylene aminopolysiloxanes with different values of m ₂ and n ₂ in the above formula by changing the amounts of the polyoxyalkylene compound and morpholine added, and examined their physical properties. The results shown in Table 2 were obtained.

[Table] Reference example 3 The following in the reactor ( _G3 is −(CH ₂ −) ₃ O−(CH ₂ CH ₂ O−) ₉ H) Polyoxyalkylene polysiloxane
198.3g and below (N is an integer from 3 to 10) 115.0 g of aminopolysiloxane and 186.7 g of octamethylcyclotetrasiloxane were charged, heated at about 110°C for 2 hours while blowing nitrogen gas, and dehydrated. 0.6 g of octamethylcyclotetrasiloxane solution with 10% KOH added to
was added and reacted at 140°C for 5 hours. Next, add ethylene chlorohydrin to this reaction system.
After adding 5.0g and reacting at 90℃ for about 2 hours, the following formula was obtained. A polyoxyalkylene aminopolysiloxane (hereinafter abbreviated as A-7) represented by the formula was obtained, and had physical properties of a viscosity of 1630 cS and a refractive index of 1.4358. Reference Example 4 201.6 g of aminopolysiloxane used in Reference Example 3 above, 280.6 g of octamethylcyclotetrasiloxane and the formula After mixing 17.8g of methylpolysiloxane shown by
An amino group-containing dimethylpolysiloxane having a refractive index of 430 cS and a refractive index of 1.4334 was obtained (hereinafter abbreviated as B-3). Example 1 After weighing 40 ml of 0.2% sodium oleate aqueous solution into a graduated cylinder with internal volume 200 ml,
After shaking 20 times to create foam, 2 ml of the 10% aqueous siloxane solution obtained in the above reference example was added dropwise, and the amount of foam was measured after 2 minutes.
The results shown in the table were obtained (hereinafter referred to as foam breaking). Next, after shaking this product 20 more times, we examined the amount of foam immediately after this shaking, and the results were as shown in Table 3 (hereinafter referred to as antifoaming properties). ).

[Table] Example 2 After weighing 100 ml of 0.2% sodium oleate aqueous solution into a measuring cylinder with an internal volume of 1000 ml, 5 ml of the 10% aqueous siloxane solution obtained in the above reference example was added to it.
was added, and then air was continuously introduced into the mixture at a rate of 1/min through a glass filter, and the change in foaming amount over time was examined, and the results shown in Table 4 below were obtained.

[Table] Example 3 (1) Preparation of antifoam composition Dimethylpolysiloxane 27 with a viscosity of 1000 cS
g, 3 g of fine powder silica Aerosil A-380 (manufactured by Nippon Aerosil Co., Ltd., trade name) and organopolysiloxanes A-1 to A-7 or organopolysiloxanes B-1 to B-3 obtained in the above reference examples. A uniform paste-like material was prepared by uniformly stirring and mixing 70 g for 15 minutes. (2) Measurement of foaming amount Add 0.3% polyoxyethylene nonyl phenyl ether to a graduated cylinder with an internal volume of 1000 ml.
Weigh out 200 ml of an aqueous solution of Emulgen 909 (manufactured by Kao Atlas Co., Ltd., trade name), add 0.02 ml (10 ppm) of a 10% aqueous solution of the antifoam composition obtained above, and then add a caustic soda solution to the solution. pH 12
Then, we maintained the temperature at 80℃ and continuously introduced air at a rate of 1/min through a glass filter, and examined the change in the amount of foaming over time. The results shown in the table were obtained. (3) High temperature dilution stability (oil spot test) Add caustic soda to the 10% aqueous solution of the antifoam composition prepared in (1) above to adjust its pH to 12, and add hydrochloric acid to the 10% aqueous solution of the antifoam composition prepared in (1) above. Its pH is 2
The sample was heated to 130℃ for 30 minutes in a Kutzker tester, then taken out.
When the state of the solution was observed, the results were shown in Table 5.

【table】

Claims (1)

[Claims] 1. General formula [Here, R ¹ is a hydrogen atom or 1 having 1 to 10 carbon atoms
A valent hydrocarbon group, G is the formula -R ³ _d O _e - (C ₂ H ₄ -) _f - (R ² O-) _g A (where A is a hydrogen atom, a monovalent hydrocarbon having 1 to 10 carbon atoms) group, acyl group or isocyanate group, R ² is a divalent hydrocarbon group having 3 to 10 carbon atoms, R ³ is a carbon number 2
~10 divalent hydrocarbon groups, d and e are each 0 or 1, f and g are positive integers of 1 or more), an oxyalkylene group represented by the general formula -R ⁴ NH ₂ (where R ⁴ is a divalent hydrocarbon group having 2 to 10 carbon atoms), or a general formula (Here, R ⁵ is a divalent hydrocarbon group having 2 to 10 carbon atoms,
Z is a group represented by a monovalent group having 2 to 10 carbon atoms containing at least one primary or secondary amino group bonded to an adjacent carbon atom via a nitrogen atom, a,
b and c are 0, 1, 2 or 3 respectively, a+b+
c=3, m and n are each positive integers of 1 or more, l is 0 or a positive integer of 100 or less], and the organopolymer contains an oxyalkylene group and an amino group-containing organic group in its molecule. A self-emulsifying antifoaming agent characterized by containing siloxane as a main ingredient.