WO2011069868A2

WO2011069868A2 - Defoaming compositions

Info

Publication number: WO2011069868A2
Application number: PCT/EP2010/068638
Authority: WO
Inventors: Willibald Burger; Holger Rautschek; Josef Wimmer
Original assignee: Wacker Chemie Ag
Priority date: 2009-12-08
Filing date: 2010-12-01
Publication date: 2011-06-16
Also published as: DE102009047638A1; WO2011069868A3

Abstract

The invention relates to novel compositions containing (A) at least one organosilicon compound from units of the formula R_a (R¹O) _bSiO_(4-a-b)/2 (I), wherein R is the same or different and may represent a hydrogen atom or a monovalent, optionally substituted SiC-bound aliphatic hydrocarbon group with 1 to 30 C atoms, R¹ is the same or different and may represent a hydrogen atom or a monovalent, optionally substituted hydrocarbon group with 1 to 4 C atoms, a is 1, 2 or 3 and b is 0 or 1, with the proviso that the sum is a+b<3 and that the organosilicon compound has a viscosity of 0.00001 m²/s to 0.01 m²/s at 25°C and 101.425 kPa; (B) at least one organosilicon compound from units of the formula R_c(R¹O) _dSiO_(4-a-b)/2 (II), wherein R and R¹ are defined as above, c is 1, 2 or 3 and d is 0 or 1, with the proviso that the sum is c+d<3 and that the organosilicon compound has a viscosity of at least 1 m²/s at 25°C and 101.425 kPa; and (C) at least one additive selected from (C1) filler particles and/or (C2) organosiloxane resin from units of the formula R² _e (R³O) _fSiO_(4-e-f)/2 (III), wherein R² is defined as R and R³ is defined as R¹, e is 0, 1, 2 or 3 and f is 0, 1, 2 or 3, with the proviso that the sum is e+f<3 and that in less than 50% of all units of formula (III) the sum of e+f equals 2 in the organosiloxane resin.

Description

defoamer

The invention relates to compositions which

Organosilicon compounds having different viscosities, processes for their preparation and their use as defoamers.

In many liquid, especially aqueous systems which contain surface-active compounds as desired or unwanted constituents, can be formed by foaming

Problems arise when these systems are brought into more or less intensive contact with gaseous substances, for example in the gassing of waste water, intensive stirring of liquids, in distillation, washing or dyeing processes or in filling operations.

The control of this foam can be done by mechanical means or by the addition of defoamers. Defoamers based on siloxanes have proven particularly useful. Defoamers based on siloxanes are prepared, for example, according to US Pat. No. 3,383,327 A by heating hydrophilic silica in polydimethylsiloxanes. By application of basic

Catalysts can improve the effectiveness of such defoamers, such as disclosed in US 3,560,401A.

An alternative is the distribution of hydrophobized

Silica in a polydimethylsiloxane, e.g. B. according to DE 29 25 722 AI.

However, the effectiveness of the antifoams obtained is usually in need of improvement. Thus, US-A 4,145,308

for example, an antifoam preparation which, in addition to a polydiorganosiloxane and silica, also contains a copolymer of (CH ₃ ) ₃ SiO _2/2 and SiO _{2 building} blocks. Copolymers of (CH ₃ ) ₃ SiO _2/2 and SiO _{2 building} blocks should also be advantageous in combination with siloxanes which carry terminal long alkyl groups, such as in EP-A 301,531

(corresponding US 4,919,843 A).

The use of cross - linked, partly already rubber ^¬ like polydimethylsiloxanes to increase the

Contribute defoamer effect. Reference may be made, for example, to US Pat. No. 2,632,736, EP-B 163 541, EP-B 217 501, EP-A 273 448 and EP-A 434 060. However, these products are in

Generally very viscous and difficult to handle or further processable.

As an alternative to cross-linked siloxanes, linear highly viscous polydimethylsiloxanes are also used in antifoam formulations.

According to the teaching of US Pat. No. 4,395,352, a significant improvement in the defoaming action is already achieved if

Polydimethylsiloxanes with a viscosity of up to

30000 mm ² / s are used in the formulations.

In EP-B 163 398 oils are up to a viscosity of up to 200000 mm ² / s to improve the defoamer in

Mixtures with oils of 100-5000 mm ² / s, silicone resin and

Silica used. In this case, the defoaming effect can already be improved by the fact that the highly viscous siloxane is added later. US 4,460,493 describes antifoams for non-aqueous liquids consisting of polydimethylsiloxanes and a

special polyether substituted silicone resin. Although high molecular weight siloxanes but no mixtures of siloxanes having different viscosities or molecular weights are used. CN 1583212 describes antifoam agents, wherein the polydimethylsiloxane used has a viscosity of more than 100,000 mm ² / s, which is complicated in the further processing.

EP-B 270 898 teaches the use of polydimethylsiloxanes having a viscosity of more than 15 kPa's as defoamers in acidic media. In order to be able to distribute this extremely viscous polymer in aqueous media, it must be in one

complicated process with a surfactant and a specific substituted with polyether groups and therefore expensive

Silicone resin are mixed.

However, the known defoamer formulations do not always have a sufficiently long-lasting effectiveness in strongly foaming surfactant-rich systems or are because of the high

Viscosity due to the achieved branching or

Degree of crosslinking difficult to handle.

It was the task Defoamer formulations

to provide, in which the above-mentioned disadvantages are avoided.

The invention relates to compositions comprising (A) at least one organosilicon compound of units of the formula

R _a (R ⁱ O) _b SiO _(4- ab) / 2 (I), where

R may be the same or different and one

Hydrogen atom or a monovalent, optionally substituted, SiC-bonded aliphatic

Hydrocarbon radical having 1 to 30 carbon atoms, R ^{1 may be the} same or different and a

Hydrogen atom or a monovalent, optionally substituted hydrocarbon radical having 1 to 4

Carbon atoms means

a is 1, 2 or 3,

b is 0 or 1,

with the proviso that the sum a + b <3, 'and where the coefficients a and b are chosen such that these

Organosilicon compound at 25 ° C and 101.425 kPa has a viscosity of 0.00001 m ² / s to 0.01 m ² / s.

(B) at least one organosilicon compound of units of the formula

R _c (R ¹ 0) _d SiO _(4-ab) / 2 (II) wherein R and R ¹ have the abovementioned meaning, c is 1, 2 or 3,

d is 0 or 1,

with the proviso that the sum is c + d <3, and where the coefficients c and d are chosen such that these

Organosilicon compound at 25 ° C and 101.425 kPa a

Viscosity of at least I m ² / s has.

and

(C) at least one additive selected from the group of (Cl) filler particles,

(C2) organopolysiloxane resin of units of the formula

R ² e (R ³ O) _f SiO ₍₄ -ef) / 2 (HI) wherein

R ^{2 may be the} same or different and is a hydrogen atom or a monovalent, optionally substituted, SiC-bonded hydrocarbon radical having 1 to 30

Carbon atoms means R ^{3 may be the} same or different and is a hydrogen atom or a monovalent, optionally substituted hydrocarbon radical having 1 to 4 carbon atoms, e is 0, 1, 2 or 3 and

f is 0, 1, 2 or 3,

with the proviso that the sum is e + f <3 and in less than 50% of all units of formula (III) in the organopolysiloxane resin the sum e + f is equal to 2, and their mixtures of (Cl) and (C2).

Examples of radicals R are alkyl radicals, such as the methyl, ethyl, n-propyl, n-butyl, i-butyl, n-pentyl, cyclopentyl, n-hexyl radical, n-heptyl radical, n- Octyl radical, i-octyl radical, n-nonyl radical, n-decyl radical, n-dodecyl radical and n-octadecyl radical.

Examples of substituted radicals R are 3, 3, 3-trifluoro-n-propyl radical, cyanoethyl, glycidoxypropyl, polyalkylene glycol propyl, aminopropyl, aminoethylaminopropyl, methacryloxypropyl radicals.

Preferably, the radical R is an optionally substituted hydrocarbon radical having 1 to 18 carbon atoms, preferably a linear alkyl radical having 1 to 18 carbon atoms,

particularly preferably a methyl, n-hexyl, n-heptyl, n-octyl and n-dodecyl radical, in particular a methyl radical.

Examples of radical R ¹ are hydrogen atom and alkyl radicals, such as the methyl, ethyl, n-propyl, iso-propyl and n-butyl radicals.

Preferably, the radical R ^{1 is} a hydrogen atom or a methyl or ethyl radicals.

B is preferably 0 or 1, more preferably 0. Preferably, d is 0 or 1, more preferably 0.

The organosilicon used as component (A)

Compounds of units of the formula (I) are preferably linear organopolysiloxanes.

In the context of the present invention, the term organopolysiloxanes is intended to encompass both polymeric, oligomeric and dimeric siloxanes.

The component (A) used according to the invention is preferably essentially linear organopolysiloxanes of the formula R ₃ Si (O-SiR ₂ ) _n O-SiR ₃ (IV), where the radical R has the meaning given above and Index n, which determines the degree of polymerization of the polysiloxane (IV) and thus the viscosity, preferably an integer of 5 to 500, preferably 100 to 300, is.

Although not indicated in formula (IV), these may

Organopolysiloxanes up to 10 mol%, but preferably less than 0.2 mol% based on the sum of all siloxane units, other siloxane units, such as = sio _1/2 , -Si0 _3/2 - and Si0 _4/2 - units containing.

Preferably, less than 5 mol%, in particular less than 1 mol%, of the radicals R, in each case based on the sum of the radicals R in formula (IV), have the meaning of hydrogen atom.

The component (B) used according to the invention is preferably essentially linear organopolysiloxane of the formula R ₃ Si (O-SiR ₂ ) _m O-SiR ₃ (V), where the radical R has the meaning given above and the index m, which determines the degree of polymerization of the polysiloxane (V) and thus the viscosity, preferably a integer greater than 1500, preferably greater than 2000. Preferably, m is at most 10,000, preferably at most 5000

Although not indicated in formula (V), these may

Organopolysiloxanes up to 1 mol%, but preferably less than 0.02 mol% based on the sum of all siloxane units, other siloxane units, such as sSi0 _1/2 -, -Si0 _3/2 - and Si0 _4/2 - units containing.

Preferably, less than 5 mol%, in particular less than 1 mol%, of the radicals R, in each case based on the sum of the radicals R in formula (V), have the meaning of hydrogenatora.

The organosilicon compounds (A) and (B) can be prepared by any desired methods known to date in organosilicon chemistry of the polymerization of cyclic siloxanes or polycondensation of silanol-terminated oligomers.

The weight ratio of component (A) to component (B) is preferably 100: 10 to 100: 0.1, in particular 100: 5 to 100: 1,

The viscosity of the mixture of (A) and (B) at 25 ° C and

101.325 kPa is preferably less than 100000 mm ² / s, preferably less than 50 000 mm ² / s, more preferably less than 20 000 mm ² / s, which is for further processability

is advantageous.

The compositions according to the invention comprise additive (C) in amounts of preferably 0.1 to 30 parts by weight, preferably 1 to 15 parts by weight, based in each case on 100 parts by weight of component (A) and (B).

The additive (C) used according to the invention may be exclusively component (C1), exclusively component (C2) or a mixture of components (C1) and (C2), the latter being preferred.

The component (Cl) is preferably

powdery, preferably hydrophobic, fillers.

Component (Cl) preferably has a BET surface area of from 20 to 1000 m ² / g, a particle size of less than 10 m and an agglomerate size of less than 100 μm.

Examples of the component (Cl) are silica

(Silicic acids), titanium dioxide, aluminum oxide, metal soaps, quartz powder, PTFE powder, fatty acid amides z. B.

Ethylenebisstearamide, finely divided hydrophobic polyurethanes.

Preferably, as component (Cl), silica

(Silicic acids), titanium dioxide or alumina with a BET surface area of 20 to 1000 m ² / g, a particle size of less than 10 μιη and an agglomerate size of less than 100 μηα used.

Particularly preferred as component (Cl) are silicic acids, in particular those having a BET surface area of 50 to

800 m ² / g. These silicas may be fumed or precipitated silicas. They are as component (Cl) both

pretreated silicas used, ie commercially available hydrophobic silicas, as well as hydrophilic silicas. The degree of hydrophobization is determined by the number of methanol

characterized. This is according to DE 2107082 AI

determined by adding 0.2 g of the silica in 50 ml of water become. While stirring methanol is added until the silica is completely wetted and suspended in the liquid. The methanol number is the percentage of methanol in the liquid mixture that just wets the silica. As pretreated hydrophobic silicic acids are preferably silicic acids having a methanol number of more than 30

in particular of more than 50 used. examples for

Commercially available hydrophobic silicas which can be used according to the invention are HDK® H2000, a fumed silica treated with hexamethyldisilazanes having a BET surface area of 140 m ² / g (commercially available from Wacker-Chemie GmbH, Germany) and a precipitated with

Polydimethylsiloxane treated silica with a BET surface area of 90 m ² / g (commercially available under the

Designation "Sipernat D10" at Degussa AG, Germany).

If hydrophobic silicas are to be used as component (Cl), hydrophilic silicas can also be rendered hydrophobic in situ if this is advantageous for the desired activity of the defoamer formulation. Procedure for

Hydrophobization of silicas are widely known. The in situ hydrophobing of the hydrophilic silica can be z. B. by heating for several hours in the component (A) or in a mixture of (A) and (B) dispersed

Silica to temperatures of 100 to 200 ° C take place. The reaction may be assisted by the addition of catalysts, such as KOH, and hydrophobing agents, such as short-chain OH-terminated polydimethylsiloxanes, silanes or silazanes. This treatment is also the use of

Commercially available hydrophobic silicic acids possible and can contribute to the improvement in efficacy.

Another possibility is the use of a combination of in situ hydrophobicized silicas with commercially available hydrophobic silicas. In this case, preferably 1 part each In situ hydrophobized silica 0.2 to 5 parts

pretreated hydrophobized silica used.

Examples of radicals R ² are the radicals indicated for radicals R.

The radical R ² is preferably an optionally substituted hydrocarbon radical having 1 to 18 carbon atoms, preferably a hydrocarbon radical having 1 to 6 carbon atoms, particularly preferably a methyl radical.

Examples of radical R ³ are the radicals indicated for the radical R ¹ .

Preferably, the radical R ^{3 is} a hydrogen atom or a

Methyl or ethyl radical.

Preferably, the value of e is 3 or 0.

The optionally used component (C2) according to the invention are preferably silicone resins of units of the formula (II) in which less than 30%, preferably less than 5% of the units in the resin have the sum e + f equal to 2 , More preferably, component (C2) is um

Organopolysiloxane resins consisting essentially of R ² ₃ SiOi _{/ 2} (M) and Si0 _4/2 (Q) units with R ^{2 have} the abovementioned meaning; these resins are also referred to as MQ resins. The molar ratio of M to Q units is preferably in the range of 0.5 to 2.0, more preferably in the range of 0.6 to 1.0. In addition to the M and Q units of the MQ resins may optionally contain small amounts of RSi0 _3/2 (T) units or R ⁴ ₂ Si0 _2/2 (D) units, in amounts of 0.01 to 20 mol %, but preferably less than 5 mol% based on Si atoms, wherein R ^{4 is} a radical R ² or a radical -OR ³ , and R ² and R ^{3 have} the meaning given above. These silicone resins may also contain up to 10% by weight of Si-bonded hydroxy or alkoxy groups -OR ³ . Preferably, these Organopolysiloxanharze (C2) at 25 ° C have a viscosity greater than 1000 mPas or are solids. The weight average determined by gel permeation chromatography

Molecular weight (based on a polystyrene standard) of these resins is preferably 200 to 200,000 g / mol, in particular 1,000 to 20,000 g / mol.

Component (C2) are commercially available products or can be prepared by methods common in silicon chemistry, for. For example, "Parsonage, J.R. Kendrick, D.A. (Science of Materials and Polymers Group, University of Greenwich, London, ÜK SE18 6PF) Spec. Publ. - R. Soc. Chem. 166, 98-106, 1995 ", US-A 2,676,182 or EP-A 927,733.

If the additive (C) used according to the invention is a mixture of components (Cl) and (C2), the weight ratio of (Cl) to (C2) in the mixture is preferably 0.01 to 50, particularly preferably 0 , 1 to 7.

Apart from the components (A), (B) and (C), the

compositions according to the invention contain all other substances, as they have also been used in defoamer formulations, such as. B. water-insoluble organic compounds (D). The term "water insoluble" is intended in the sense of

present invention, a solubility in water at 25 ° C and a pressure of 101.325 kPa of at most 3 percent by weight are understood. The optionally used component (D) are preferably water-insoluble organic compounds having a boiling point greater than 100 ° C at the pressure of the surrounding atmosphere, ie at 900 to 1100 hPa, in particular those selected from mineral oils, native oils,

Isoparaffins, polyisobutylenes, residues from the

Oxo-alcohol synthesis, esters of low molecular weight synthetic carboxylic acids, fatty acid esters, e.g. Octyl stearate,

Dodecyl palmitate, fatty alcohols, low molecular weight ethers

Alcohols, phthalates, esters of phosphoric acid and waxes.

The compositions according to the invention contain

water-insoluble organic compound (D) in amounts of preferably 0 to 1000 parts by weight, more preferably 0 to 100 parts by weight, based in each case on 100 parts by weight of the total weight of components (A), (B) and (C).

The components used in the process according to the invention may each be a type of such a component as well as a mixture of at least two types of a respective component.

Preferably, the inventive

Compositions around those that

(A) at least one organosilicon compound of the formula (IV)

(B) at least one organosilicon compound of the formula (V),

(C) at least one additive selected from

(Cl) filler particles and / or

(C2) organopolysiloxane resin of units of formula (III), and optionally

(D) water-insoluble organic compound

contain .

With particular preference the compositions according to the invention are those containing (A) 100 parts by weight of an organosilicon compound of the formula (IV),

(B) 0.1 to 10 parts by weight of an organosilicon compound of the formula (V)

(C) 0.1 to 30 parts by weight of an additive selected from (Cl) filler particles and / or

(C2) Organopolysiloxane resin of units of formula (II), and optionally

(D) water-insoluble organic compound.

The compositions of the invention are preferably viscous clear to opaque colorless liquids.

Optionally modified polysiloxanes, which may be linear or branched and carry at least one polyether moiety, may be added in amounts of preferably from 1 to 500 parts by weight per 100 parts by weight of components A to D, preferably in amounts of from 2 to 3, as further components for the preparation of the defoamer formulations according to the invention 200 parts by weight per 100 parts by weight of components A to D, more preferably in amounts of 3 to 100

Parts by weight per 100 parts by weight of components A to D. Such polyether-modified polysiloxanes are known and z. As described in EP 1076073 A.

The compositions according to the invention have a viscosity of preferably 100 to 2,000,000 mPas, more preferably of 10,000 to 80,000 mPas each at 25 ° C and 101,325 kPa. Preference is given to formulations in which the in the

Oscillating viscosity measurement (according to DIN 53019-1 and cited standards) at an amplitude of 1% and a frequency of 1Hz measured loss factor (quotient of loss modulus and storage modulus) is less than 10, in particular less than 5. The compositions according to the invention may be solutions, dispersions or powders.

The preparation of the compositions of the invention can be prepared by known methods, such. B. by mixing all

Components are made, such. B. using high

Shear forces in colloid mills, dissolvers or rotor-stator homogenizers. The mixing process can be carried out at reduced pressure to the mixing of air, which z. B. is contained in highly dispersed fillers to prevent. Subsequently, if necessary, the in situ hydrophobing of the

Fillers are made.

It is Z. B. possible first to mix the components (A) and (C) and, if necessary, to heat and then add component B.

In a preferred embodiment, however, only

Components (A) and (B) mixed, then components (C) is added and then the mixture is baked and homogenized.

The invention furthermore relates to emulsions containing compositions according to the invention,

Emulsifiers and

water

If the compositions according to the invention are emulsions, it is possible to use all emulsifiers which are known to the person skilled in the art for the preparation of silicone emulsions, such as, for example, As anionic, cationic or nonionic

Emulsifiers. Emulsifier mixtures are preferably used, wherein at least one nonionic emulsifier, such as. B.

Sorbitan fatty acid esters, ethoxylated sorbitan fatty acid esters, ethoxylated fatty acids, ethoxylated linear or branched alcohols having 10 to 20 carbon atoms and / or glycerol esters, should be included. Furthermore, known as thickeners compounds such as polyacrylic acid, polyacrylates, cellulose ethers such as carboxymethyl cellulose and hydroxyethyl cellulose,

Polyurethanes, natural thickeners, such as. As xanthan gum, as well as preservatives and other conventional additives known in the art are added.

The continuous phase of the emulsions according to the invention is preferably water. However, it can also according to the invention

Compositions are prepared in the form of emulsions in which the continuous phase is formed by the components (A), (B) and (C) or formed by component (D). It can also be multiple emulsions. Processes for the preparation of silicone emulsions are known.

The preparation is usually carried out by simple stirring of all constituents and optionally subsequent homogenization with jet dispersers, rotor-stator homogenizers,

Colloid mills or high-pressure homogenizers.

If the composition according to the invention is emulsions, oil in water are emulsions containing 5 to 50% by weight of components (A) to (D), 1 to 20% by weight.

Emulsifiers and thickeners and 30 to 94 wt .-% water

prefers.

The compositions of the invention may also be formulated as free-flowing powders. These are z. B. preferred when used in powdered detergents. The

Preparation of these powders starting from the mixture of

Components (A), (B), (C) and optionally (D) is carried out by methods known in the art, such as spray drying or

Build-up granulation and additives known to the person skilled in the art. The invention further powder containing Compositions according to the invention and

Carrier materials.

The powders according to the invention preferably contain 2 to 20% by weight of the composition according to the invention comprising the components (A) to (D). As a carrier come z. As zeolites, sodium sulfate, cellulose derivatives, urea and sugar are used. The powders according to the invention contain from 50 to 95% by weight of carrier materials. Other components of the powder according to the invention can, for. As waxes or organic polymers, as z. As described in EP-A 887097 and EP-A 1060778.

Another object of the present invention are detergents and cleaning compositions containing the inventive

Compositions or compositions of the invention in the form of emulsions or in the form of powders.

The compositions according to the invention can be used everywhere

be used where compositions based on

Organosilicon compounds have also been used.

In particular, they can be used as defoamers.

Another object of the present invention is a method for defoaming and / or to prevent the

Foaming of media by the inventive

Compositions or their emulsions or powders are mixed with the media.

Surprisingly, it has been found that the effectiveness of the defoamer formulations according to the invention is limited by

Additional amounts of high molecular weight polydimethylsiloxanes

can be significantly increased without the

Handling of the formulations is much more difficult. The addition of the composition according to the invention to the foaming media can be carried out directly, in suitable

Solvents, such as toluene, xylene, methyl ethyl ketone or t-butanol, dissolved, as a powder or as an emulsion. The to

Achieving the desired defoamer effect necessary amount depends z. For example, the type of medium, the temperature and the turbulence occurring.

The compositions according to the invention are preferably added in amounts of from 0.1 ppm by weight to 1% by weight, in particular in amounts of from 1 to 100 ppm by weight, to the foaming medium.

The inventive method is at temperatures of preferably -10 to + 150 ° C, more preferably 5 to 100 ° C, and the pressure of the surrounding atmosphere, that is about 900 to

1100 ° hPa, performed. The process according to the invention can also be carried out at higher or lower pressures, such as at 3000 to 4000 hPa or 1 to 10 hPa. The antifoam compositions according to the invention can be used wherever disturbing foam is to be suppressed. This is z. As in non-aqueous media, such as tar distillation or petroleum processing of the case.

In particular, the invention are suitable

Defoamer compositions for controlling foam in aqueous media, such as aqueous surfactant systems, the use in detergents and cleaners, the control of foam in wastewater systems, textile dyeing processes, in the

Natural gas scrubbing, in polymer dispersions, and for defoaming resulting in pulp production aqueous media used.

The compositions of the invention have the advantage that they are easy to handle as defoamers, and that they are characterized by a high, long-lasting efficacy in different media at low additional quantities. This is extremely beneficial both economically and ecologically. The process according to the invention has the advantage that it is simple to carry out and very economical.

In the following examples, all parts and percentages are by weight unless otherwise specified. Unless otherwise stated, the

the following examples at a pressure of the surrounding atmosphere, ie at about 1000 hPa, and at room temperature, ie about 20 ° C or a temperature which occurs when combining the

Reactants at room temperature without additional heating or cooling adjusts performed. All viscosity data given in the examples should refer to a temperature of 25 ° C.

Tests of defoamer effectiveness

1. Antifoam code AKZ

In a device according to DE-A 25 51 260 200 ml of a 4 wt .-% aqueous solution of a

Sodium alkylsulfonates (Mersolat) containing 10 mg of the

containing defoaming agent (dissolved in 10 times the amount of methyl ethyl ketone), foamed for 1 minute with two counter-rotating stirrers. Subsequently, the foam decay is recorded. From the area of the foam height versus time plot, the anti-foam index is calculated. The lower this number, the more effective the defoamer. 2. Test in black liquor

400 ml of black liquor from the pulp process (hardwood of the company ÜPM Kymmene Oy from Kuusankoski, Finland) is in a thermostated at 80 ° C 1000ml ümpumpapparatur with a

Recirculating pumping rate of 1.51 / min.

Once the foam level has reached a height of 75 mm, the defoamer (10 mg based on the components (A), (B) and (C) in the defoamer formulation) is metered in,

Foam decay time and the lowest foam level after

Addition of defoamer and incipient foam breakage is achieved are recorded. The smaller the foam decay time t1 and the lower the foam level h1, the better the fast action of a defoamer.

Thereafter, the long-term effect of the defoamer is determined, which represents the time t2 required to reach from the lowest foam level to the original foam level

(75 mm) to come. Used substances:

AI: A terminated with trimethylsiloxane groups

Polydimethylsiloxane with a viscosity of 0.0001 m ² / s A2: A trimethylsiloxane-terminated

Polydimethylsiloxane with a viscosity of 0.001 m ^z / s

A3: A trimethylsiloxane-terminated

Polydimethylsiloxane with a viscosity of 0, 008 m ² / s

VA4 (not according to the invention): condensation product with a

Viscosity of 0.0002 m ² / s prepared from octyldodecanol and one terminated with silanol groups

Polydimethylsiloxane with a chain length of 50

Siloxane units. Bl: a silanol-terminated polydimethylsiloxane having a viscosity of 3 ^m.sup.2 / s.sup.2 B2: a trimethylsiloxane-terminated one

Polydimethylsiloxane with a viscosity of 15 m ² / s

VBl (not according to the invention): A trimethylsiloxane-terminated polydimethylsiloxane having a viscosity of 0.2 m ² / s.

Cll: A hydrophilic fumed silica having a BET surface area of 300 m ² / g (available from Wacker Chemie AG, Germany under the name HDK® T30)

C12: A hydrophobic precipitated silica with a BET

Surface of 90 m ² / g and a number of methanol of 60 available from Evonik Degussa GmbH Germany under the name SIPERNAT® D10.

C21: A room temperature solid silicone resin consisting of

(according to ²⁹ Si-NMR and IR analysis) 40 mol% CH ₃ SiOi _{/ 2} -, 50 mol% S1O4 / 2-, 8 mol% C ₂ H ₅ OSi0 ₃ / 2- and 2 mol% HOSi0 _{3 2} units with a weight-average molar mass of 7900 g / mol

(based on polystyrene standard)

Additive Hl: a hydrocarbon mixture with a boiling range of 235-270 ° C. Examples 1 to 3 and Comparative Experiments Vi and V2:

The substances described in Table 1 are mixed with a dissolver and heated in the presence of 1500 ppm KOH (as a 20% solution in methanol) for 4 hours at 150 ° C and homogenized after cooling again with the dissolver.

The viscosity was measured with an MCR 301 rheometer from Anton Paar at 25 ° C. in the oscillating mode. The viscosity and the loss factor are given at an amplitude of 1% and a frequency of 1 Hz.

The compositions thus obtained were now tested for the anti-foam coefficient ÄKZ and the test in the black liquor. The results of these tests are summarized in Table 2.

For a better test, a mixture of 40 parts of the defoamer formulations mentioned in Table 1 and 60 parts of a mixture of aliphatic hydrocarbons having a viscosity of 3 mm ² / s and a flash point> 100 ° C with a laboratory dissolver at 1,000 min ^{-1 was} prepared.

The results of the effectiveness test are in the

Table 2 summarized.

Table 2: Results of the defoamer effectiveness test

The inventive examples not only have a shorter foam disintegration time and a lower foam height but also a much better long-term effect than the formulations prepared according to the prior art.

Example 4 and Comparative Experiment V3

Defoamer formulations VI and Inventive Example 1 were emulsified as follows and tested as emulsions on black liquor. There were 100 parts of a defoamer at 60 ° C with 15 parts of sorbitan monstearate (available under the name "Span 60" at Croda GmbH Nettetal) and 10 parts

Polyoxyethylene (20) sorbitan monostearate (available under the name "Tween 60" from Croda GmbH Nettetal) and diluted stepwise with 250 parts of water To this mixture was added 1 part of a polyacrylic acid (available under the name of Tween 60)

"Carbopol 934" at BF Goodrich D-Neuss), mixed and a further 123 parts of water and 1 part of a

Isothiazolinone-based preservative (available under the name "Acticide MV" from Thor-Chemie, D-Speyer) added. Subsequently, the emulsion was homogenized at 100 bar with a high pressure homogenizer and adjusted with 10% NaOH to a pH of 6-7. Table 3

The defoamer emulsions obtained not only indicate

Black liquor has an excellent effect, and they also act as very good defoamers in many other aqueous foaming formulations, such as agrochemical or detergent formulations or in aqueous polymer dispersions.

Example 5

35 ml of a 2% solution of a high molecular weight copolymer of acrylic acid, methacrylic acid stearate and pentaerythritol diallyl ether (in a molar ratio 100: 2: 0.3) (the solution, when neutralized, has a viscosity of 17 500 mm ² / s ) were placed in a beaker, and with vigorous mixing with a paddle stirrer, 10 g of the defoamer formulation of Inventive Example 1 became slow

was added, so that after stirring for 10 minutes an emulsion of the defoamer formulation was present in the polymer solution. With continued stirring, to this emulsion was added 88.5 g of light sodium carbonate and then the water was removed under continued mixing under vacuum. Thereafter, 0.5 g of a hydrophilic silica having a BET surface area of 200 m ² / g (available from Wacker-Chemie GmbH under the name HDK® N20) mixed.

A white, free-flowing powder was obtained. This has been successfully used to prevent foam in powder form

Detergents or used in powdered plant protection concentrates.

Claims

claims

Containing compositions

(A) at least one organosilicon compound of units of the formula

R _a (R ¹ 0) _b SiO _(4-ab) / 2 (I), wherein

R may be the same or different and represents a hydrogen atom or a monovalent, optionally substituted, SiC-bonded aliphatic hydrocarbon radical having 1 to 30 carbon atoms,

R ^{1 may be the} same or different and represents a hydrogen atom or a monovalent, optionally substituted hydrocarbon radical having 1 to 4 carbon atoms,

a is 1, 2 or 3,

b is 0 or 1,

with the proviso that the sum is a + b <3 and where the coefficients a and b are chosen such that at 25 ° C and 101.425 kPa this organosilicon compound has a viscosity of 0.00001 m ² / s to 0.01 m ² / s has.

at least one organosilicon compound of units of the formula

Rc (R ¹ 0) _d SiO ₍₄ ^ b) / 2 (II) wherein R and R ¹ have the abovementioned meaning, c is 1, 2 or 3,

d is 0 or 1,

with the proviso that the sum is c + d <3, and where the coefficients c and d are chosen such that these Organosilicon compound at 25 ° C and 101.425 kPa a

Viscosity of at least I m ² / s has.

and

at least one additive selected from the group of

(Cl) filler particles,

(C2) organopolysiloxane resin of units of the formula

R ² e (R ³ O) _f SiO ₍₄ -ef) / 2 (HI) wherein

R ^{2 may be the} same or different and a

Denotes a hydrogen atom or a monovalent, optionally substituted, SiC-bonded hydrocarbon radical having 1 to 30 carbon atoms,

R ^{3 may be the} same or different and a

Hydrogen atom or a monovalent, optionally substituted hydrocarbon radical having 1 to 4 carbon atoms

means

e is 0, 1, 2 or 3 and

f is 0, 1, 2 or 3,

with the proviso that the sum is e + f <3 and in less than 50% of all units of formula (III) in the organopolysiloxane resin the sum e + f is equal to 2,

and their mixtures of (Cl) and (C2).

A composition according to claim 1, characterized in that as organopolysiloxane (A) is a substantially linear organopolysiloxane of the formula

R _{3 is} Si (O-SiR ₂ ) _n O-SiR ₃ (IV), is used, wherein the radical R has the meaning given in claim 1,

and n is an integer of 5 to 500, preferably 100 to 300.

A composition according to claim 1 or 2, characterized

in that the organopolysiloxane (B) is a substantially linear organopolysiloxane of the formula

R ₃ Si (O-SiR ₂ ) _m O-SiR ₃ (V), is used, wherein the radical R has the meaning given in claim 1

and m is an integer greater than 1500, preferably greater than 2000.

A composition according to claim 1, 2 or 3, characterized

characterized in that as component (C)

(Cl) silicic acids, with a BET surface of 50 to 800 m ² / g and / or

(C2) organopolysiloxane resins consisting of R ² 3SiOi / 2 (M) - and Si0 _4/2 (Q) - units and optionally R ⁴ Si0 _3/2 (T) units, with the proviso that this organopolysiloxane contains up to 10 degrees. -% Si-bonded hydroxy or alkoxy groups

May contain OR ³

wherein R ^{4 is} a radical R ² or a radical -OR ³ and

R ² and R ^{3 have} the meaning given in claim 1,

be used.

Composition according to any one of Claims 1 to 4, characterized in that the compositions (D) water-insoluble organic compounds

contain .

Contains aqueous emulsions

Compositions according to one of Claims 1 to 5,

Emulsifiers and

water

Containing powder

Compositions according to any one of claims 1 to 5 and carrier materials.

Detergents and cleaning compositions containing compositions according to one of claims 1 to 5 or their emulsions according to claim 6 or their powders according to claim 7.

A process for defoaming and / or preventing the foaming of media by the inventive

Compositions according to one of claims 1 to 5 or their emulsion according to claim 6 or their powder according to

Claim 7 are mixed with the media.

10. The method according to claim 9, characterized in that in the pulp production resulting aqueous media

be used.