JPH0790126B2 - Antifoam - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] Textile industry, dye dyeing industry, paper pulp industry, synthetic rubber latex industry, coating industry, synthetic resin industry, and until recently, integrated circuits, lithographic printing plate fields, etc. In the industry dealing with surfactants, water-soluble polymers and the like, various problems occur due to foaming, and various antifoaming agents are used for the purpose of preventing the foaming.

TECHNICAL FIELD The present invention relates to a novel defoaming agent, and more particularly to a defoaming agent having an excellent defoaming effect (foam suppressing and defoaming effect) with respect to foaming of an aqueous solution containing a foaming substance even if added in a small amount. Is.

[Conventional technology]

Conventionally, as the defoaming agent used for such purpose, for example, various defoaming agents such as silicone type, polyalkylene glycol type, mineral oil type, fat and oil type, fatty acid type, alcohol type and mixed type thereof are used. It is used.

[Problems to be solved by the invention]

Among the above defoamers, silicone-based ones generally show good foam breaking properties, but since they are insoluble or sparingly soluble in water, scum, cissing and cratering occur when used in an aqueous system. To do Further, there are defects such as lack of sustainability of defoaming property and relatively high price.

On the other hand, the polyalkylene glycol-based defoaming agent generally has relatively few drawbacks of the silicone-based defoaming agent and is excellent in foam suppressing property, but lacks in foam breaking property.

In order to solve these problems, polyoxyalkylene group-modified organopolysiloxane has been proposed (USP 32
See 33986). However, although this one can solve the drawbacks of silicone, it lacks in defoaming property, and cannot necessarily fully exhibit the characteristics of a silicone-based defoaming agent.

Further, a urethane-modified product has been proposed as a polyalkylene glycol derivative (JP-A-57-11980). This product maintained the characteristics of the polyarylene glycol-based defoaming agent and had a considerably improved defoaming property, but it was not yet satisfactory.

[Means for solving problems]

The present inventors have conducted extensive research to improve the above-mentioned drawbacks of conventional antifoaming agents, and as a result, by reacting a specific alkylene oxide derivative, a specific silicone derivative and a specific isocyanate compound, an excellent defoaming agent can be obtained. The inventors have found that a foaming agent can be obtained and completed the present invention.

That is, the present invention provides (a) general formula (I) RO (AO) _n- H (wherein R represents an alkyl group, an alkenyl group or an alkylphenyl group having 1 to 18 carbon atoms, and AO represents 2 to 4 carbon atoms). An alkylene oxide compound represented by the general formula (II), wherein n is a number of 0 to 60. (In the formula, R ^{1 to} R ¹⁰ may be the same or different, and each is H-, CH _3- , HO-R'- and HO- (EO / PO) _2- . However, R'represents an alkylene group, (EO / PO) ₂ represents a group obtained by random and / or block copolymerization of ethylene oxide and propylene oxide, and x, y and z represent integers. ), A silicone compound having at least one alcoholic hydroxyl group, and (c) general formula (III) R ″-(NCO) m (where R ″ is a carbon-hydrogen residue or a carbamate group-substituted carbon atom). A hydrogen residue, m is an integer of 1 or more.) Is an isocyanate compound represented by the formula: (a) and (b) are —OH groups, and (c) is an —NCO group in equivalent ratio, (A): (b):
(C) is (0.5 to 0.99): (0.01 to 1): (1), and (a + b): (c) is a reaction product at a ratio of (1 to 1.99): (1) is effective. It is an antifoaming agent characterized by being contained as a component.

Specific examples of the above-mentioned compounds used as the raw material compounds in the present invention are as follows.

The compound (a) represented by the general formula (I) is a monohydric alcohol having 1 to 18 carbon atoms when n is 0, and examples of such an alcohol include methanol, ethanol,
n-propanol, isopropanol, n-butanol, isobutanol, hexanol, 2ethylhexanol, n-octanol, decanol, dodecanol,
Tetradecanol, hexadecanol, octadecanol, octadecenol, alcohol obtained from coconut oil or beef tallow oil or sperm whale oil, oxo synthetic primary alcohol, Ziegler synthetic primary alcohol, paraffin oxidation synthetic secondary Alcohols and mixtures of two or more of these various alcohols can be used.

When n is 1 or more, the compound (a) is an alkylene oxide adduct using the above alcohol as a raw material, and can be similarly used as the raw material compound of the present invention. The alkylene oxide to be added is selected from ethylene oxide, propylene oxide and butylene oxide, and may be used alone or in combination of two or more kinds. The total number of added moles is 1 to 60 moles, and they may be added randomly or in blocks, or both of them may be used in combination.

The silicone compound having one or more alcoholic hydroxyl groups as the compound (b) represented by the general formula (II) has a molecular weight of 1,500 to 1,000,000, and is, for example, Or (In the above formula, R and R ′ are alkylene groups, Alternatively, it represents a — (EO / PO) ₂ — group formed by random and / or block copolymerization of ethylene oxide and propylene oxide. ), But not limited to the above, any compound having a reactive alcoholic hydroxyl group in the organopolysiloxane chain may be used.

Examples of commercially available products include X-22-16, Shin-Etsu Silicone Co., Ltd.
0, Toray Silicone Company SF-8428, Toray Silicone Company M-1
29 etc. can be mentioned.

Examples of the isocyanate compound which gives the polyether urethane as the compound (c) of the general formula (III) include, for example, ethyl isocyanate, isopropyl isocyanate, n-butyl isocyanate, isobutyl isocyanate, phenyl isocyanate, tolyl isocyanate. Monoisocyanates such as nato, aliphatic diisocyanates such as hexamethylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,4-
Naphthylene diisocyanate, 1,5-naphthylene diisocyanate, 1,3-phenylene diisocyanate, 1,4-
Phenylene diisocyanate, isopropylberzole-2,4-diisocyanate, ω, ω 'diisocyanate-1,2-dimethylbenzol, 4,4-diphenylmethane diisocyanate, diphenyldimethylmethane-4,4'-
Aromatic diisocyanates such as diisocyanate, biphenyl-2,4'-diisocyanate, biphenyl-4,4'-diisocyanate, benzene-1,2,4-triisocyanate, 2,4,6 -Triisocyanate toluene, 4,
4 ', 4 "-triphenylmethane triisocyanate, 2,
Isocyanate compounds such as 4,4'-triisocyanate diphenyl ether, polyisocyanate in which about 3 phenyl isocyanates are engaged with a methylene bridge are mentioned.

To react these compounds, the compound (a),
(B) and (c) may be sequentially reacted, and (a)
And (c) may be reacted first and then modified with compound (b). As the reaction conditions for these reactions, the reaction temperature is preferably 50 to 80 ° C. If the temperature is less than 50 ° C, the reaction hardly progresses, and if the temperature exceeds 80 ° C, a side reaction occurs. The reaction time varies depending on the type of alcohol or isocyanate, but the reaction is completed by continuing the reaction for 1 hour or more after adding the isocyanate.

For the defoaming agent of the present invention, the reaction product obtained by the above reaction may be used as it is, or water or an organic solvent (for example, methanol, toluene, glycol ethers, methyl acetate, n-hexane, etc.). It may be used as a solution having an appropriate concentration after being dissolved in. Furthermore, depending on the case, it is also possible to use it by mixing with a known antifoaming agent.

The amount of the defoaming agent of the present invention varies depending on the type of foaming substance, the concentration of the foaming solution, the purpose of defoaming, etc., and there is no general measure, but normally the concentration of the compound of the present invention in the foaming liquid is As for, about 0.1 to 0.001% by weight is sufficient.

〔Example〕

The compounds used as raw materials in the following examples are as follows.

Compound (a) A-1: An alkylene oxide adduct of alcohol obtained by adding about 10 mol of propylene oxide and about 40 mol of ethylene oxide to 1 mol of lauryl alcohol.

Molecular weight: about 2,530 A-2: Alkylene oxide adduct of alcohol obtained by adding about 10 mol of propylene oxide and about 10 mol of ethylene oxide to 1 mol of ethanol.

A-3: Linebole 79 (Oxo-method synthetic alcohol manufactured by Shell Chemical Co., Ltd., average molecular weight 126) An alkylene oxide adduct of alcohol obtained by adding about 4 mol of propylene oxide and about 15 mol of ethylene oxide to 1 mol.

A-4: Ethanol A-5: About 3 parts of ethylene oxide per mol of nonylphenol
An adduct with added moles.

Compound (b) B-1: Toray Silicone Co., Ltd. SF-8427 Alcohol-modified silicone, carbinol-modified type at both ends, hydroxy equivalent of about 1,200 B-2: Shin-Etsu Silicone Co., Ltd. X-22-160 Both-end carbi Nol-modified type, hydroxy equivalent of about 2,80
0 B-3: Toray Silicone Co., Ltd. M-129 branched alkyl alkylene oxide modified type, hydroxy equivalent of about 700 Compound (c) C-1: xylylene diisocyanate C-2: hexamethylene diisocyanate C-3: Tolylene diisocyanate Further, the defoaming test is carried out by the following method.

Defoaming test Polyvinyl alcohol (saponification degree about 86%, polymerization degree about 170
0) 400 g of an aqueous solution containing 4% by weight and an antifoaming agent of 80 ppm is charged in a double tube kept at 60 ° C. Drain the liquid from the bottom and place it on the liquid surface.
A drop port was provided at a height of 50 cm, and circulation was performed at a flow rate of 120 / hr. The bubble height after 10 minutes of circulation was read, the circulation was stopped at the same time, and the bubble height after 10 minutes was read. The foam height was observed from the foam height after 10 minutes of circulation, and the foam height was observed from the foam height after 10 minutes of standing.

Example 1 In a four-necked flask equipped with a stirrer, about 10 mol of propylene oxide and about 10 mol of ethylene oxide per mol of lauryl alcohol.
113.8 g (0.9 equivalent ratio) of alkylene oxide adduct of alcohol (the above compound A-1) obtained by adding 40 mol, alcohol-modified silicone SF-8427 (compound B)
-1) 18.0 g, and DBU {1,8-diaza-bicyclo (5.4.0) undecene-7} 2-ethylhexanoate 0.05 g as a catalyst were charged, and the system was preheated to 70 ° C while substituting nitrogen. did. At this temperature, 4.7 g (1 equivalent ratio) of xylene diisocyanate (Compound C-1) was gradually added over 10 minutes to cause a reaction, and then stirring was continued for another 90 minutes to complete the reaction.

After the completion of the reaction, 2.6 g of activated clay was added and an adsorption treatment was carried out for 30 minutes. Then, the decolorization and the catalyst were removed by filtering this to obtain an antifoaming agent. The results of the defoaming test are shown in Table 1.

Examples 2 to 5 Using the compounds shown in Table 1 and the equivalent ratio, a reaction was performed in the same manner as in Example 1 to obtain an antifoaming agent, and an antifoaming test was conducted. The results are also shown in Table 1.

Comparative Examples 1 to 6 As a control, the defoaming test result when no defoaming agent was added is set as Comparative Example 1, and the defoaming test results when various defoaming agents are used in Comparative Example 2 and below are shown in Table 1. Shown in.

〔The invention's effect〕

As is clear from the results shown in Table 1, the antifoaming agent of the present invention is excellent in use in a small amount by using the product obtained by reacting the components (a), (b) and (c). It exhibits defoaming and defoaming properties.

The defoaming agent of the present invention is excellent in dynamic defoaming effect by using the component (a) as a raw material component.
It is clear from the results of Comparative Example 3 lacking the component (a) and the respective examples of the present invention, and by using the component (b) as a raw material component, the defoaming effect at static time (foam breaking property) is excellent. This is shown in the results of Comparative Example 5.

Note that, as shown in Comparative Example 6, the effect of the present invention cannot be obtained by simple mixing.

Claims (1)

[Claims] (A) General formula (I) RO (AO) _n- H (wherein R represents an alkyl group, an alkenyl group or an alkylphenyl group having 1 to 18 carbon atoms, and AO represents 2 to 4 carbon atoms). An alkylene oxide compound represented by the formula (II), wherein n is a number from 0 to 60. (In the formula, R ^{1 to} R ¹⁰ may be the same or different, and each is H-, CH _3- , HO-R'- and HO- (EO / PO) _Z- . However, R'represents an alkylene group, (EO / PO) _Z represents a group obtained by random and / or block copolymerization of ethylene oxide and propylene oxide, and x, y and z represent integers. ), A silicone-based compound having at least one alcoholic hydroxyl group, and (c) general formula (III) R ″-(NCO) m A hydrogen residue, m is an integer of 1 or more.), An isocyanate compound represented by the formula: (A): (b):
(C) is (0.5 to 0.99): (0.01 to 1): (1), and (a + b): (c) is a product obtained by reacting at a ratio of (1 to 1.99): (1) is effective. An antifoaming agent, which is contained as an ingredient.