EP1954370A1

EP1954370A1 - Organosilicon compound-containing compositions

Info

Publication number: EP1954370A1
Application number: EP06819499A
Authority: EP
Inventors: Holger Rautschek; Heinz Hoffmann; Christian Fehn
Original assignee: Wacker Chemie AG
Current assignee: Wacker Chemie AG
Priority date: 2005-11-23
Filing date: 2006-11-15
Publication date: 2008-08-13
Also published as: DE102005055839A1; JP2009513809A; WO2007060123A1; CN101312773A; KR20080051147A; US20080293606A1

Abstract

The invention relates to compositions containing at least one type of carrier oil and at least one type of particulate filler on the condition that a contact angle of the carrier oil and the filler which is measured with water used as an ambient phase is less than 40°. The use of said compositions for defoaming media and/or preventing foam formation therein is also disclosed.

Description

Organosilicon compounds containing compositions

The invention relates to compositions based on organosilicon compounds and particulate fillers, which are characterized by selected contact angles, processes for their preparation and their use as defoamers.

In many liquid, especially aqueous systems which contain surface-active compounds as desired or even undesired constituents, foaming may cause problems if these systems are brought into more or less intensive contact with gaseous substances, for example when fumigating waste water, during intensive Stirring 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 DE-AS 15 19 987 by heating hydrophilic silica into polydimethylsiloxanes. By using basic catalysts, the effectiveness of such defoamers can be improved, as disclosed for example in DE-OS 17 69 940. An alternative is the distribution of hydrophobized silica in a polydimethylsiloxane, e.g. according to DE-OS 29 25 722. It is essential for the effectiveness that the silica was sufficiently hydrophobed and is no longer wetted by water, but only of water-methanol mixtures, if they contain more than 50% methanol.

The need for a good hydrophobization of a silica used in anti-foaming agents is also emphasized in EP-A 967252. The importance of the hydrophobicity of the particles for the development foaming action is described by Kobayashi (J. Colloid Interface Sci., 156 (2), 294-8, 1993) and Marinova et al. (Langmuir, 18 (9), 3399-3403, 2002).

However, the known defoamer formulations do not always have a sufficiently long-lasting effectiveness in strongly foaming surfactant-rich systems.

The invention relates to compositions containing at least one carrier oil and at least one particulate

Filler with the proviso that the contact angle of the carrier oil to the filler measured with water as the surrounding phase is less than 40 °, preferably less than 30 °, more preferably less than 20 °, in particular 5 ° to 15 °.

Preferably, the compositions according to the invention are those containing

(A) at least one organosilicon compound selected from (Al) organopolysiloxanes of units of the formula

R _a (R ¹ O) _b SiO ₍ 4-ab) / 2 (I),

wherein

R may be the same or different and is hydrogen or a monovalent, optionally substituted, SiC-bonded hydrocarbon radical,

R ^{1 may be the} same or different and is hydrogen or a monovalent, optionally substituted hydrocarbon radical, a is 0, 1, 2 or 3, b is 0, 1, 2 or 3, with the proviso that the sum is a + b <_3 and in at least 50% of all units of the formula (I) in the organosilicon compound (A1) the sum a + b is equal to 2,

and

(A2) Organopolysiloxane resins from units of the formula

R ² _c (R ³ O) _d SiO (4-cd) / 2: n)

wherein

R ^{2 may be} identical or different and is hydrogen atom or a monovalent, optionally substituted, SiC-bonded hydrocarbon radical, R ^{3 may be} identical or different and represents a hydrogen atom or a monovalent, optionally substituted hydrocarbon radical, c 0, 1, 2 or 3 and d is 0, 1, 2 or 3, with the proviso that the sum is c + d <_3 and less than 50

% of all units of the formula (II) in the organopolysiloxane resin (A2) the sum c + d is 2, wherein component (A) has a viscosity at 25 ° C of 5 to

5,000,000 mm ² / s, preferably 50 to 50,000 mm ² / s, as well as

(B) at least one particulate filler,

with the proviso that the contact angle of component (A) to component (B) measured with water as the surrounding phase is less than 40 °. In the context of the present invention, the term organopolysiloxanes is intended to encompass both polymeric, oligomeric and dimeric siloxanes.

The contact angle determination is already known. In this case, the contact angle θ of a fluid phase (2) on a solid phase (3) with a second fluid phase (1) as the surrounding phase is measured (see FIGS. 1 and 2). For this purpose, see e.g. on "Wettability" edited by John C. Berg, Surfactant Series Volume 49, Marcell Dekker Inc. 1993 ISBN 0-8247-9046-4, Chapter 5 TD Blake: "Dynamic Contact Angels and Wetting Kinetics" especially on S 252 First paragraph and Figure Ib referenced.

Preferably, the contact angle of component (A) to component (B), ie the angle which a drop of component (A) forms on the surface of component (B) with water as the surrounding phase, is determined by means of pressing (Method 1) . For this purpose, a stainless steel cylinder with component (B) is filled and pressed with a pressure of at least 10 MPa, preferably 50 to 100 MPa, with a polished stainless steel punch. The tablet-shaped pressure thus produced is placed horizontally in a vessel filled with water. On a horizontal surface of the compact then a drop of the component (A) is applied. If component (A) is heavier than water, the droplet is applied from the top to the top surface of the compact (Figure 1) when component (A) is lighter than water on the bottom surface of the compact (Figure 2). The angle which the tangent formed at the three-phase point forms at the droplet / surrounding phase interface to the droplet / solid phase interface is measured in a suitable manner, in particular with a goniometer. The measurement of the contact angle of component (A) to component (B) can also be effected by applying a drop of component (A) to a surface which is chemically identical to component (B). For example, when using highly dispersed silicic acid (SiO 2) as the component (B), a quartz glass surface can be used. If the surface of this silica has been modified, the measurement should be carried out on an equally modified quartz glass surface (Method 2).

The compositions of the invention contain as component (A) preferably a mixture of siloxanes (Al) and (A2), wherein in each case based on 100 parts by weight of (Al), more preferably 0.1 to 100 parts by weight, especially 1 to 20 parts by weight, (A2) be used.

Examples of radical R are hydrogen atom, alkyl radicals, such as the methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert. Butyl, n-pentyl, isopentyl, neo-pentyl, tert-pentyl radical, hexyl radicals, such as the n-hexyl radical, heptyl radicals, such as the n-heptyl radical, octyl radicals, such as the n-octyl radical, the iso-octyl radical and the 2, 2, 4-trimethylpentyl radical, nonyl radicals, such as the n-nonyl radical, decyl radicals, such as the n-decyl radical, dodecyl radicals, such as the n-dodecyl radical; Alkenyl radicals, such as the vinyl and allyl radicals; Cycloalkyl radicals, such as norbornyl, cyclopentyl, cyclohexyl, cycloheptyl radicals and methylcyclohexyl radicals; Aryl radicals, such as the phenyl and the naphthyl radical; Alkaryl radicals, such as o-, m-, p-tolyl radicals, xylyl radicals and ethylphenyl radicals; Aralkyl radicals, such as the benzyl radical, the CC and the ß-phenylethyl radical and the 2-propenylphenylrest.

Preferably, less than 5%, in particular less than 1%, of all radicals R in the organopolysiloxanes (A) have the meaning of hydrogen atom. Examples of substituted radicals R are 3,3,3-trifluoro-n-propyl radical, cyanoethyl, glycidoxypropyl, polyalkylene glycol propyl, aminopropyl, aminoethylaminopropyl, methacryloxypropyl radicals.

Radical R is preferably hydrogen or optionally halogen atoms, hydroxyl groups, polyether groups, mercapto groups, acrylate groups, methacrylate groups, epoxy groups, cyano groups, amino groups substituted hydrocarbon radicals having 1 to 30 carbon atoms, particularly preferably alkyl groups having 1 to 20 carbon atoms, cyclo - alkyl groups having 5 to 10 carbon atoms, phenyl groups or alkylaryl groups, such as 2-phenylpropyl groups, in particular methyl, ethyl, octyl, phenyl, 2-phenylpropyl groups.

Examples of radical R ¹ are the radicals mentioned as radical R.

Radicals R ¹ are preferably hydrogen atoms or hydrocarbon radicals optionally substituted by halogen atoms, hydroxyl groups, polyether groups, mercapto groups, acrylate groups, methacrylate groups, epoxy groups, cyano groups, amino groups having from 1 to 30 carbon atoms, more preferably hydrogen or hydrocarbon radicals of 1 to 4 carbon atoms, in particular methyl or ethylres- te.

B is preferably 0 or 1, more preferably 0.

Component (A1) is preferably branched or linear organopolysiloxanes. The component (A1) used according to the invention is preferably essentially linear organopolysiloxane of the formula

R _{3 is} Si (O-SiR ₂ ) _n O-SiR ₃ (IV),

wherein radicals R have one of the abovementioned meanings and index n, which determines the degree of polymerization of the polysiloxane (IV) and thus the viscosity, in the range from 1 to 10,000, preferably in the range of 2 to 1000, particularly preferably in the range of 10 to 200, lies.

Although not indicated in formula (IV), these organopolysiloxanes can be up to 10 mole percent based on the total of all siloxane units, other siloxane units, such as SiO _3/2 and SiO _4/2 ~ units containing.

The organosilicon compounds (Al) used in the compositions according to the invention have a viscosity of preferably from 5 to 5,000,000 mPas, more preferably from 50 to

50,000 mPas, in particular from 200 to 15,000 mPas, each measured at 25 ° C.

The organosilicon compounds (Al) may be prepared by any method heretofore known in organosilicon chemistry, e.g. by cohydrolysis of the corresponding silanes. Such methods are known to the person skilled in the art.

In particular, organopolysiloxanes having alkyl groups containing more than one carbon atom or having aralkyl groups are known to be preferably prepared by hydrosilylation reaction of the corresponding Si-bonded hydrogen-containing organosilicon compounds with olefins. In the hydrosilylation lierungs be organosilicon compounds with Si-bonded hydrogen (1) with the corresponding aliphatically unsaturated compounds (2), such as ethylene, propylene, 1-hexene, 1-octene, 1-dodecene, 1-hexadecene and 1-octadecene, in the presence of the addition of Si-bonded hydrogen to aliphatic multiple bond (hydrosilylation) promoting catalysts (3), such as metals from the group of platinum metals or compounds or complexes of the group of platinum metals, reacted by known methods.

Examples of radical R ² in component (A2) are the radicals specified for radical R.

Radical R ² is preferably hydrocarbon radicals having 1 to 30 carbon atoms, optionally substituted by halogen atoms, hydroxyl groups, polyether groups, mercapto groups, acrylate groups, methacrylate groups, epoxy groups, cyano groups, amino groups, particularly preferably hydrocarbon radicals having 1 to 6 Carbon atoms, in particular the methyl radical.

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

Radical R ³ is preferably hydrogen or hydrocarbon radicals having 1 to 4 carbon atoms, in particular hydrogen, methyl or ethyl radicals.

Preferably, the value of c is 3 or 0.

Preferably, the value of d is 0 or 1. The optionally used component (A2) according to the invention is preferably silicone resins in which less than 30%, particularly preferably less than 5%, of all units of the formula (II) in the resin have the sum c + d equal to 2.

Particularly preferably, component (A2) to ganopolysiloxanharze OR, consisting essentially of R ² 3Si0i _/ 2 (M) - and SiO _4/2 (Q) units where R ² is as defined above; 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. These silicone resins may also contain up to 10% by weight of free hydroxy or alkoxy groups.

Preferably, these Organopolysiloxanharze (A2) at 25 ° C have a viscosity greater than 1000 mPas or are solids. The weight-average molecular weight (based on a polystyrene standard) of the resins (A2) determined by gel permeation chromatography is preferably 200 to 200,000 g / mol, in particular 1,000 to 20,000 g / mol.

Component (A2) are commercially available products or can be synthesized according to methods common in silicon chemistry, e.g. according to "Parsonage, J. R .; Kendrick, D.A. (Science of Materials and Polymers Group, University of Greenwich, London, UK SE18 6PF) Spec. Publ. - R. Soc. Chem. 166, 98-106, 1995 ", US-A 2,676,182 or EP-A 927,733.

The component (B) is preferably powdered, preferably hydrophobic, fillers.

Examples of component (B) are silica (silicas), titanium dioxide, alumina, metal soaps, quartz flour, PTFE powder, fatty acid amides such as ethylenebisstearamide, finely divided hydrophobic polyurethanes, with silica (silicic acids), titanium dioxide and aluminum oxide being preferred.

Component (B) preferably has a BET surface area of from 20 to 1000 m ² / g, particularly preferably from 50 to 800 m ² / g, in particular from 80 to 500 m ² / g.

Component (B) preferably has a particle size of less than 10 μm, more preferably from 0.01 to 5 μm.

Component (B) preferably has an agglomerate size of less than 100 μm, more preferably of 0.1 to 10 μm.

Particularly preferred as component (B) 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. It is possible to use as component (B) both pretreated silicic acids, ie commercially available hydrophobic silicic acids, as well as hydrophilic silicic acids. Examples of commercially available hydrophobic silicas which can be used according to the invention, a pyrogenic, hexamethyldisilazane-treated silica having a BET surface are of 140 m ² / g (available commercially under the brand HDK ^® H2000 from Wacker-Chemie GmbH, Germany) and a precipitated polydimethylsiloxane-treated silica having a BET surface area of 90 m ² / g (commercially available under the name Sipernat® D10 from Degussa AG, Germany).

If hydrophobic silicas are to be used as component (B), hydrophilic silicas can also be rendered hydrophobic in situ if this is advantageous for the desired activity of the antifoam formulation. Procedure for Hydrophobization of silicas are widely known. In situ hydrophobing of the hydrophilic silica can be carried out, for example, by heating the silica dispersed in component (A) for several hours at temperatures of from 100 to 200 ^° C. 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 possible with the use of commercially available hydrophobic silicas.

Another possibility is the use of a combination of in situ hydrophobicized silicas with commercially available hydrophobic silicas.

Preference is given to surface-modified silicic acid (B)

Silicas, in particular silicas modified with organosilicon compounds.

However, it is essential in the selection of component (B) as a function of component (A) that the contact angle to component (A) is less than 40 °.

The compositions according to the invention contain component (B) in amounts of preferably 0.1 to 30 parts by weight, more preferably 1 to 15 parts by weight, in particular 2 to 10 parts by weight, based in each case on 100 parts by weight of (A).

In addition to the components (A) and (B), the compositions according to the invention may contain all other substances, such as have hitherto been used in antifoam formulations, such as, for example, water-insoluble organic compounds (C). The term "water-insoluble" in the context of the present invention, a solubility in water at 25 ° C and a pressure of the surrounding atmosphere, ie between 900 and 1100 hPa, to be understood by a maximum of 3 weight percent,

The optionally used component (C) are preferably water-insoluble organic compounds having a boiling point greater than 100 ⁰ 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, from the Oxoalkoholsynthese, esters of low molecular weight synthetic carboxylic acids, fatty acid esters such as octyl stearate, dodecyl palmitate, fatty alcohols, ethers of low molecular weight alcohols, phthalates, esters of phosphoric acid and waxes.

The novel compositions contain water-insoluble organic compound (C) 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) and (B).

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

The novel compositions are particularly preferably those which contain component (A1), component (A2), component (B) and optionally component (C), the contact angle of component (A) to component (B) being measured by Water as ambient phase is less than 40 °. The compositions according to the invention are very particularly preferably those which comprise 100 parts by weight of component (A1), 1 to 20 parts by weight of component (A2), 1 to 20 parts by weight of component (B) and, if appropriate

0 to 1000 parts by weight of water-insoluble organic compound (C), wherein the contact angle of the component (A) to the component (B) measured with water as the surrounding phase is less than 40 °.

In particular, the compositions according to the invention are those which consist of

100 parts by weight of component (Al),

1 to 20 parts by weight of component (A2),

1 to 20 parts by weight of highly dispersed silicic acid as a component

(B) and optionally

(C) water-insoluble organic compound, wherein the contact angle of the component (A) to the component (B) measured with water as the surrounding phase is less than 30 °.

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

The compositions according to the invention have a viscosity of preferably 100 to 10 000 000 mPas, more preferably from 500 to 50 000 mPas, in particular from 1000 to 10 000 mPas, in each case at 25 ° C. If desired, the compositions according to the invention can be further processed into emulsions or powders.

The preparation of the compositions of the invention may be carried out by known methods, e.g. by mixing all components, e.g. using high shear forces in colloid mills, dissolvers or rotor-stator homogenizers. The mixing process may be carried out at reduced pressure to prevent the mixing in of air, e.g. contained in highly dispersed fillers to prevent. Subsequently, if necessary, the in situ hydrophobing of the fillers can take place.

If the compositions according to the invention are to be further processed into 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 e.g. anionic, cationic or nonionic emulsifiers. Emulsifier mixtures are preferably used, it being necessary to contain at least one nonionic emulsifier, such as, for example, 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. Furthermore, compounds known as thickeners, such as polyacrylic acid, polyacrylates, cellulose ethers, such as carboxymethylcellulose and hydroxyethylcellulose, natural gums, such as xanthan gum and polyurethanes, as well as preservatives and other conventional additives known to those skilled in the art may be added.

The continuous phase of the emulsions according to the invention is preferably water. However, compositions according to the invention may also be prepared in the form of emulsions in which the continuous phase is constituted by components (A) and (B) formed or formed by component (C). 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, if appropriate, 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 emulsions containing from 5 to 50% by weight of components (A) to (C), from 1 to 20% by weight of emulsifiers and thickeners and from 30 to 94% by weight of water is preferred.

The compositions according to the invention can also be formulated into free-flowing powders. These are e.g. preferred for use in powdered detergents. The preparation of these powders starting from the mixture of components (A), (B) and, if appropriate, (C) is carried out by methods known to the person skilled in the art, such as spray-drying or build-up granulation and additives known to the person skilled in the art.

The novel powders preferably contain 2 to 20% by weight of components (A) to (C). As carriers come e.g. Zeolite, sodium sulfate, cellulose derivatives, urea and sugar. Further constituents of the powders according to the invention may e.g. Waxes or organic polymers, as they are e.g. in EP-A 887097 and EP-A 1060778 are described.

The compositions according to the invention can be used everywhere where compositions based on organosilicon compounds have hitherto also been used. In particular, they can be used as defoamers. Another object of the present invention are detergents and cleaners containing the compositions of the invention.

Another object of the present invention is a method for defoaming and / or foam prevention of media, characterized in that the composition according to the invention is mixed with the medium.

The addition of the composition according to the invention to the foaming media can be carried out directly, mixed with suitable solvents, such as toluene, xylene, methyl ethyl ketone or t-butanol, as a powder or as an emulsion. The amount necessary to achieve the desired defoamer action depends, for example, on the type of medium, the temperature and the turbulence that occurs.

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 carried out at temperatures of preferably -10 to +150 ⁰ C, more preferably 5 to 100 ⁰ 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 disruptive foam is to be suppressed. This is the case, for example, in non-aqueous systems such as tar distillation or petroleum processing. INS The compositions according to the invention are particularly suitable for controlling foam in aqueous surfactant systems, for use in detergents and cleaners and for controlling foam in sewage treatment plants. Furthermore, the compositions according to the invention can be used in textile dyeing processes, in natural gas scrubbing, in polymer dispersions and for defoaming aqueous media obtained during pulp production.

The compositions of the invention have the advantage that they are easy to handle as defoamers, and that they are distinguished by a high, long-lasting effectiveness in a wide variety of media at low levels. This is extremely beneficial both economically and ecologically.

The method according to the invention has the advantage that the selection of suitable combinations of (A) and (B) is unerring and simple to carry out. Elaborate performance tests on a variety of conceivable material combinations are not required. Thus, the process is very economical.

In the following examples, all parts and percentages are by weight unless otherwise specified. Unless stated otherwise, the following examples are at a pressure of the surrounding atmosphere, ie at about 1000 hPa, and at room temperature, ie about 20 ⁰ C or a temperature which occurs when combining the reactants at room temperature without additional heating or cooling - puts, performed. All viscosity data given in the examples should refer to a temperature of 25 ° C. Measurement of contact angles (Figures 1 and 2) Method 1

In a stainless steel cylinder with a diameter of 13 mm and a height of 40 mm 20 mm component (B) are filled and pressed with a pressure of 70 MPa with a polished stainless steel punch. The thus prepared pressing (3) is placed horizontally in a glass vessel filled with water (phase 1). On a horizontal surface of the compact, a drop (phase 2) of the component (A) is then applied with a Pasteur pipette. If component (A) is heavier than water (1), the drop (2) is applied from the top to the top surface of the compact (3) (Figure 1) if component (A) is lighter than water on the bottom Surface of the compact (Fig.2). The angle θ which the tangent formed at the three-phase point forms at the droplet / surrounding phase interface to the droplet / solid phase interface is measured with a goniometer. The process is repeated several times and the mean and scatter (standard deviation) are calculated.

Method 2

The measurement of the contact angle of component (A) to component (B) takes place on a quartz glass surface, which was optionally modified analogously to component (B). For this purpose, a quartz glass plate is placed horizontally in a glass vessel filled with water. On a horizontal surface of the quartz glass pane, a drop of the component (A) is then applied with a Pasteur pipette. If component (A) is heavier than water, the drop is applied to the top surface from above, if component (A) is lighter than water on the bottom surface. The angle θ which the tangent formed at the three-phase point forms at the droplet / surrounding phase interface to the droplet / solid phase interface is measured with a goniometer. The process is repeated several times and the mean and scatter (standard deviation) are calculated.

To show that Method 1 and Method 2 bring the same results within the error limits, a contact angle measurement using a compact of fumed silica with a BET surface area of 300 m ² / g (Kauflieh available from Wacker-Chemie GmbH, Germany under labeled HDK® T30), and the contact angle of an oil with a viscosity of 150 mm ² / s, which consists of methylphenylsiloxane and dimethylsiloxane units and is terminated by trimethylsiloxy groups, with water as the surrounding phase. For comparison, the measurement was carried out with a quartz glass disk instead of the compact. The results are shown in Table 1.

Table 1:

In the following examples, the contact angles according to method 2 were determined on quartz glass plates, which were treated in exactly the same way as the silicas used.

The contact angles of quartz glass / water as a measure of the hydrophobicity of the silica were determined in an analogous manner with a water drop (phase 2) and air as the surrounding phase (phase 1) (FIG. 3). Tests of defoamer effectiveness

1. Antifoam characteristic AKZ In a device according to DE-A 25 51 260 200 ml of a 4 wt .-% aqueous solution of a Natriumalkylsulfona- tes (Mersolat), the 10 mg of the examined defoamer (dissolved in 10 times the amount of Methyl ethyl ketone), foamed for 1 minute with two counter-rotating stirrers. Afterwards 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. Stirring test

300 ml of a solution containing 1% by weight of a defoamer-free washing powder were foamed for 5 minutes with a stirrer at a speed of 1000 revolutions / min. Subsequently, 100 .mu.l of a 10 wt .-% solution of the defoamer in methyl ethyl ketone were added and stirring continued for another 25 minutes. During the entire time the foam height is recorded.

As a measure of effectiveness, the average foam height based on the foam height without antifoam is calculated after 2-3 minutes. The lower this value, the more effective the defoamer.

3. Test in the washing machine with a powdered detergent 0.1 g defoamer was added to 100 g of the defoamer-free washing powder. The washing powder was then added to a drum washing machine (Miele Novotronik W918 without fuzzy logic type) together with 3500 g of clean cotton laundry. subse- The washing program is started and the foam height recorded over a period of 55 minutes. From the foam notes determined over the entire period (0 no foam measurable to 6 effervescence) the average foam note is determined. The lower this is, the more effective the defoamer will be over the entire period.

example 1

85 parts of a silicone oil (Al-I) having a viscosity of 1000 mm ² / s, which consists of methylphenylsiloxane and dimethylsiloxane units and terminated with trimethylsiloxy groups, 5 parts of a solid at room temperature silicone resin (A2-1) of trimethylsiloxy and SiO 2 ~ Units in the molar ratio 0.61 / 1 having a weight-average molecular weight of 5728 g / mol (based on polystyrene standard) and a content of Si-bonded hydroxyl groups of 0.8 wt.%, Dissolved in 5 parts of a hydrocarbon mixture (CI) with a boiling range of 235-270 ⁰ C (kauflich obtainable under the name Exxsol D 100 S & case of dust Co Nuremberg, Germany), 5 parts of a fumed silica (BI) with a BET surface area of 400 m ² / g (kauflich obtainable in the Wacker-Chemie GmbH, Germany under the name HDK® T40) and 0.7 parts of a 20 wt .-% methanolic KOH are mixed with a dissolver and heated to 150 ⁰ C for 4 hours. A defoamer with a viscosity of 4800 mPas was obtained. The composition thus obtained was now checked for the anti-foam characteristic AKZ, the Ruhr test and the test in the washing machine. To measure the contact angle of a quartz glass sheet in the above-mentioned mixture of (Al-I) and (A2-1) and the cata- lyst is immersed and also heated to 150 ⁰ C 4 Sunden. After cooling and draining (vertical storage for 24 hours) of the free siloxane, the glass is immersed in water and a Drop the mixture of (Al-I) and (A2-1) described above onto the surface to determine the contact angle. The results of these tests are summarized in Table 2.

Example 2

90 parts of a silicone oil (Al-2) of the formula Me ₃ Si-O- [SiMeOCt-O-! 20-SiMe ₃ (Oct is an octyl radical, Me is a methyl radical) having a viscosity of 221 mPas, 5 parts of a Room temperature solid silicone resin (A2-2) from trimethylsiloxy and SiÜ2 units in the molar ratio 0.61 / 1 having a weight average molecular weight of 5728 g / mol (based on polystyrene standard) and a content of Si-bonded hydroxyl groups of 0.8 wt. %, 5 parts of a fumed silica (B-2) with a BET surface area of 300 m ² / g (commercially available from Wacker-Chemie GmbH, Germany under the name HDK® T30), and 0.7 parts of a 20 wt .-% methanolic KOH are mixed with a dissolver and heated to 150 ⁰ C for 4 hours. There was obtained a defoamer with a viscosity of 1800 mPas. The composition thus obtained was now checked for the anti-foam characteristic AKZ, the stirring test and the test in the washing machine.

To measure the contact angle, a quartz glass plate with the above mixture of (Al-2) and (A2-2) and the catalyst is also heated to 150 ⁰ C for 4 hours. After cooling and draining (vertical storage for 24 hours) of the free siloxane, the glass is immersed in water and a drop of the above-described mixture of (Al-2) and (A2-2) is added to the surface to determine the contact angle. The results of these tests are summarized in Table 2.

Example 3

90 parts of a polydimethylsiloxane (Al-3) with a viscosity of 8000 mm ² / s, 5 parts of a solid at room temperature Sii conharzes (A2-3) consisting of ²⁹ Si-NMR and IR analysis of 90.7 mol% CH ₃ SiO ₃₇₂ -, 4.3 mol% C ₂ H ₅ O (CH ₃ ) SiO _{2Z 2} -, 4 mol % HO (CH ₃ ) SiO _2/2 and 1 mol% (CH ₃ ) ₂ SiO _2/2 units having a weight-average molar mass of 10710 g / mol (based on polystyrene standard), 5 parts of a fumed silica (B-3) with a BET surface area of 400 m ² / g (commercially available from Wacker-Chemie GmbH, Germany under the name HDK® T40) and 0.7 parts of a 20 wt .-% methanolic KOH are with a dissolver and heated to 150 ⁰ C for 4 hours. There was obtained a defoamer with a viscosity of 6400 mPas. The composition thus obtained was now checked for the anti-foam characteristic AKZ, the stirring test and the test in the washing machine. To measure the contact angle, a quartz glass plate with the above-mentioned mixture of (Al-3) and (A2-3) and the catalyst is also heated to 150 ⁰ C for 4 hours. After cooling and draining (vertical storage for 24 hours) of the free siloxane, the glass is immersed in water and a drop of the above-described mixture of (Al-3) and (A2-3) is added to the surface to determine the contact angle.

The results of these tests are summarized in Table 2.

Comparative Example 1

95 parts of a silicone oil (Al-VI) having a viscosity of 1000 mm ² / s, consisting of methylphenylsiloxane and dimethylsiloxane units and terminated with trimethylsiloxy groups, 5 parts of a fumed silica (B-VI) having a BET surface area of 400 m ² / g (commercially available from Wacker-Chemie GmbH, Germany under the name HDK® T40) and 0.7 parts of a 20 wt .-% methanolic KOH are mixed with a dissolver and heated to 150 ⁰ C for 4 hours. An opaque mixture with a viscosity of 30400 mPas was obtained. The composition thus obtained has now been Checked foam number AKZ, the stirring test and the test in the washing machine.

To measure the contact angle, a quartz glass plate with the above-mentioned polysiloxane (Al-Vl) and the catalyst e- benfalls 4 hours at 150 ⁰ C is heated. After cooling and draining (vertical storage for 24 hours) of the free siloxane, the glass is immersed in water and a drop (Al-VI) is added to the surface to determine the contact angle.

Comparative Example 2

90 parts of a polydimethylsiloxane (A1-V2) having a viscosity of 350 mm ² / s, 5 parts of a solid at room temperature silicone resin (A2-V2) of trimethylsiloxy and SiC> 2 units in the molar ratio 0.61 / 1 with a weight-average Molar mass of 5728 g / mol (based on polystyrene standard) and a content of silicon bonded hydroxyl groups of 0.8 wt.%, Dissolved in 5 parts of a hydrocarbon mixture (C-V2) with a boiling range of 235-270 ⁰ C (commercially available under the name Exxsol D 100 S in Staub & Co Nuremberg, Germany) 5 parts of a fumed silica (B-V2) with a BET surface area of 200 m ² / g (commercially available from Wacker-Chemie GmbH, Germany under the Designation HDK® N20) are mixed with a dissolver. A defoamer with a viscosity of 2556 mPas was obtained. The composition thus obtained was now checked for the anti-foam characteristic AKZ, the stirring test and the test in the washing machine.

To measure the contact angle, a quartz glass disk is immersed in water and a drop of the mixture of Al and A2 is added to the surface to determine the contact angle.

The results of these tests are summarized in Table 2. Table 2

In the comparison experiments V1 and V2, the foam liquor overflowed very quickly.

It is clear that although in the examples a practically identical contact angle to water (ie hydrophobicity) was achieved, the compositions according to the invention have a superior activity.

Claims

claims

1. Compositions comprising at least one carrier oil and at least one particulate filler with the proviso that the contact angle of the carrier oil to the filler measured with water as the surrounding phase is less than 40 °.

2. Compositions according to claim 1, characterized in that they are those which (A) at least one organosilicon compound selected from (Al) organopolysiloxanes of units of the formula

R _a (R ¹ O) _b SiO ₍ 4-a- _b ) / 2: D

wherein

R may be the same or different and is hydrogen or a monovalent, optionally substituted, SiC-bonded hydrocarbon radical, R ^{1 may be the} same or different and is hydrogen or a monovalent, optionally substituted hydrocarbon radical, a is 0, 1, 2 or 3, b 0, 1, 2 or 3, with the proviso that the sum a + b <_3 and in at least 50% of all units of the formula (I) in the organosilicon compound (Al) the sum a + b is 2,

and

(A2) Organopolysiloxane resins from units of the formula

R ² _c (R ³ O) _d SiO _(4- cd) / 2 (II), wherein

5 000 000 mm ² / s, and

(B) contain at least one particulate filler, with the proviso that the contact angle of the component (A) to

Component (B) measured with water as the surrounding phase is less than 40 °.

3. Compositions according to claim 1 or 2, characterized in that they contain as component (A) a mixture of siloxanes (Al) and (A2).

4. Compositions according to one or more of claims 1 to 3, characterized in that the contact angle of the component (A) to the component (B) is less than 20 °.

5. Compositions according to one or more of claims 1 to 4, characterized in that component (A2) is organopolysiloxane resins consisting essentially of R ² ₃ Si0i _{/ 2} (M) - and SiO _4/2 (Q) units consist of R ^{2 is the} same meaning as above.

6. Compositions according to one or more of claims 1 to 5, characterized in that component (B) is silica (silicas), titanium dioxide and alumina.

7. Compositions according to one or more of claims 1 to 6, characterized in that component (B) is silica.

8. Washing and cleaning compositions containing the compositions according to one or more of claims 1 to 7.

9. A method for defoaming and / or foam prevention of media, characterized in that the composition is mixed according to one or more of claims 1 to 7 with the medium.

10. The method according to claim 9, characterized in that the composition in amounts of from 0.1 ppm by weight to 1 wt .-% is added to the foaming medium.