DE102011005607A1 - Preparing organo-modified polysiloxanes useful for preparing polyurethane foams and as emulsifiers, comprises e.g. coupling siloxanes containing silicon-hydrogen bond with organic compounds containing hydroxy groups - Google Patents

Abstract

Preparing organo-modified polysiloxanes, comprises (i) coupling siloxanes containing silicon-hydrogen bond with organic compounds containing hydroxy groups or (C-C) multiple bond, (ii) contacting a reaction mixture obtained in the coupling reaction, with particles having a hydrophobic surface, and (iii) removing the particles from the reaction mixture. Independent claims are also included for: (1) the organo-modified polysiloxanes, obtainable by the above method; and (2) a composition comprising the organo-modified polysiloxanes obtainable by the above method.

Description

The invention relates to a process for the preparation of organomodified polysiloxanes by linking siloxanes containing Si-H bonds with organic compounds containing OH groups or C-C multiple bonds, the organomodified polysiloxanes thus prepared and their use.

Organomodified siloxanes are used in numerous technical applications due to their unique properties such as water repellency, interfacial activity, temperature stability, etc. These include the stabilization of polyurethane foams, the use as emulsifiers, the use in release coatings and many more.

The preparation of organomodified polysiloxanes and their use is described in numerous documents. For example, describe EP 0 048 984 and the publications cited therein various linear siloxanes having multiple pendant groups (cyano groups, polyoxyalkylene groups and phenyl groups) for use in polyester polyurethane foam.

In the not yet published DE 10 2007 046 736 For example, a process is described in which organomodified polysiloxanes are prepared which have an equilibration step and a hydrosilylation or dehydrogenative condensation step.

In the preparation of organomodified polysiloxanes by linking Si-H bonds containing siloxanes with OH groups or C-C multiple bonds containing organic compounds, reaction mixtures are often obtained, which have turbidity. By a simple filtration of the reaction mixtures of activated carbon, the turbidity could not be removed.

It was therefore an object of the present invention to provide a method with which organomodified polysiloxanes can be provided which are free of turbidity.

In JP 08-319352 describes a method in which unwanted low molecular weight siloxanes are removed from the equilibration mixture from equilibration mixtures, by addition of hydrophobicized inorganic particles and subsequent separation of the particles.

Surprisingly, it has been found that the turbidity in such reaction mixtures can be removed by addition of hydrophobized particles to reaction mixtures which are obtained by linking Si-H bonds containing siloxanes having OH groups or C-C multiple bonds containing organic compounds.

The present invention therefore relates to a process for preparing organomodified polysiloxanes by linking siloxanes having Si-H bonds with organic compounds containing OH groups or C-C multiple bonds, which is characterized in that the reaction mixture obtained in the coupling reaction with particles, which have a hydrophobic surface is brought into contact and the particles is then removed from the reaction mixture again.

Likewise provided by the present invention are organomodified polysiloxanes obtainable as well as those containing them. Compositions and their use, eg. In the production of polyurethane foams or polyester polyurethane foams.

The process according to the invention has the advantage that turbidity occurring in a simple manner (turbidity visible to the naked eye) in the product mixture can be separated off safely in the preparation of organomodified polysiloxanes. Removal of turbidity alone by centrifugation was not always possible and did not completely remove turbidities. Removal by distillation also proved impossible.

By means of the method according to the invention, product compositions are now obtainable which no longer have turbidity visible to the naked eye.

Turbidity-containing product compositions or organomodified polysiloxanes, or product compositions or organomodified polysiloxanes which are not according to the invention were treated and z. B. are used as foam stabilizers in the production of PU foams, it may cause changes in performance z. In terms of flow behavior or cell structure, compared to those organomodified polysiloxanes prepared according to the invention.

The polysiloxanes or compositions produced according to the invention and a process for their preparation are described below by way of example, without the invention being restricted to these exemplary embodiments. Given below, ranges, general formulas, or classes of compounds are intended to encompass not only the corresponding regions or groups of compounds explicitly mentioned, but also all sub-regions and sub-groups of compounds obtained by removing individual values (ranges) or compounds can be. If documents are cited in the context of the present description, their contents are intended to form part of the disclosure content of the present invention.

The process according to the invention for the preparation of organomodified polysiloxanes by linking siloxanes containing Si-H bonds with OH groups or CC multiple bonds comprises organic compounds, characterized in that the reaction mixture obtained in the linking reaction with particles having a hydrophobic surface , Is brought into contact and the particles are then removed from the reaction mixture again. The bringing into contact is preferably carried out by adding the particles to the reaction mixture and subsequent or simultaneous good mixing. This can, for. B. by stirrers, settler mixer devices or the like. The removal of the particles may preferably be carried out by filtration, decanting or centrifuging.

In the method according to the invention can be used as particles having a hydrophobic surface z. As hydroxides, carbonates, silicates, clays, natural silica gels or plastic materials are used. The particles are preferably selected from plastic particles and from particles of metal or semimetal oxides, hydroxides or carbonates, organic silicones, silicates, clays and celluloses, which have optionally been rendered hydrophobic. Preferred particles are those having silicon or alumina (s). If silicon dioxide particles are used, in particular silica particles (silica particles) are preferred. The silicas may be fumed or precipitated silicas or natural diatomaceous earth. Preferred silicas are precipitated silicas. Suitable precipitated silicas having a hydrophobic surface are, for. For example, such as those under the trade names Sipernat ^® D10, D13 or D17, as offered by the Evonik Degussa GmbH.

The particles used preferably have an average particle size d ₅₀ , determined by means of a multisizer with 100 μm capillary according to ASTM C 690 - 1992 , of <50 μm, preferably from> 1 μm to <20 μm.

In the process according to the invention, preference is given to using those particles which have a specific surface area (N ₂ , determined in accordance with FIG ISO 5794-1 , Annex D) of> 25 m ² / g, preferably from 50 to 300 m ² / g and preferably from 75 to 200 m ² / g.

The hydrophobicity of the surface of preferably used particles can be determined, for example, by determining the methanol wettability, as in EP 1281735 described, be determined. Hydrophobic particles in the context of the present invention have a methanol wettability of at least 10%. The methanol wettability is preferably greater than 50%, preferably greater than 60% and particularly preferably from 60 to 100%.

Preference is given to using particles which have an average particle size d ₅₀ of <50 μm, a specific surface area of> 25 m ² / g and a methanol wettability of greater than or equal to 10%. Particular preference is given to using particles having an average particle size d ₅₀ . of> 1 to <20 microns, have a specific surface area of 75 to 200 m ² / g and a methanol wettability of greater than 50%.

The mass of particles added to the reaction mixture is preferably from 0.1 to 10% by mass, preferably from 0.3 to 5% by mass, and more preferably from 0.5 to 2% by mass, based on the reaction mixture.

Depending on the embodiment of the process according to the invention, it may be advantageous if an equilibration step is carried out before or after the linking step in which siloxanes containing Si-H bonds are linked to organic compounds containing OH groups or C-C multiple bonds. Preferably, the equilibration step is performed prior to the linking step.

The siloxanes used according to the invention can be prepared in a known manner according to the prior art. Thus, the linear siloxanes z. B. be synthesized by first producing a siloxane with only one SiH functionality at one end by ring-opening polymerization of cyclosiloxanes, especially Hexamethylcyclotrisiloxan. The ring-opening polymerization of cyclosiloxanes is well known to those skilled in the art and is described, for example, in U.S. Pat J. Chojnowski, M. Cypryk, Synthesis of Linear Polysiloxane, Chapter 1 in RG Jones et al., Silicone Containing Polymers, Kluwer, 2000 , described.

hergestellt, wobei
R¹ unabhängig voneinander gleiche oder verschiedene, geradkettige oder verzweigte, aliphatische oder aromatische, gegebenenfalls halogenierte, gegebenenfalls ungesättigte Kohlenwasserstoffreste mit 1 bis 8 Kohlenstoffatomen, vorzugsweise mit einem Kohlenstoffatom (Methylrest), sind, k = 0 bis 200, vorzugsweise 1 bis 100, bevorzugt 1 bis 30 und besonders bevorzugt von 1 bis 20, wobei k beim Vorhandensein nur einer Verbindung der Formel (I) die tatsächliche Anzahl der mit dem Index k gekennzeichneten Einheiten und bei Vorhandensein von mehreren Verbindungen der Formel (I) den Mittelwert der Anzahl der Einheiten darstellt,
R² unabhängig voneinander gleich oder verschieden R¹ oder eine Gruppe der Formel A-B-D-Q darstellt, mit der Maßgabe, dass wenigstens ein R² ungleich R¹ ist, wobei
A ein Sauerstoffatom, eine CH₂-Gruppe oder eine CH=CH-Gruppe, vorzugsweise ein Sauerstoffatom oder eine CH₂-Gruppe, ist,
B eine CH₂-Gruppe oder ein zweiwertiger Rest, ausgewählt aus linearen oder verzweigten, gesättigten, ein- oder mehrfach ungesättigten Alkyl-, Aryl-, Alkylaryl- oder Arylalkyl-Oxygruppen mit 2 bis 20 Kohlenstoffatomen oder eine Gruppe der Formel -CH₂-O-(CH₂)₄-O- ist,
D eine Gruppe der allgemeinen Formel (II) -(C₂H₄O)_n(C₃H₆O)_o(C₁₂H₂₄O)_p(C₈H₈O)_q(C₄H₈O)_r- (II) ist, mit
n, o, p, q und r voneinander unabhängige ganze Zahlen von 0 bis 50, wobei die Summe der Indizes n + o + p + q + r größer oder gleich 3 ist und die allgemeine Formel II ein statistisches Oligomer oder ein Blockoligomer darstellt, und
Q ein Rest, ausgewählt aus Wasserstoff, linearen oder verzweigten, gesättigten, ein- oder mehrfach ungesättigten, Alkyl-, Aryl-, Alkylaryl- oder Arylalkylgruppen mit 1 bis 20 Kohlenstoffatomen, gegebenenfalls ein oder mehrere Heteroatome enthaltend, gegebenenfalls ein oder mehrere Carbonylgruppen enthaltend, gegebenenfalls mit einer ionischen organischen Gruppe modifiziert, die beispielsweise die Heteroatome Schwefel, Phosphor und/oder Stickstoff enthalten kann, ist.Preferably, with the process according to the invention, organomodified polysiloxanes of the general formula (I)

produced, wherein
R ¹ independently of one another are identical or different, straight-chain or branched, aliphatic or aromatic, optionally halogenated, optionally unsaturated hydrocarbon radicals having 1 to 8 carbon atoms, preferably having one carbon atom (methyl radical), k = 0 to 200, preferably 1 to 100 1 to 30 and more preferably from 1 to 20, wherein k in the presence of only one compound of formula (I) the actual number of units marked with the index k and in the presence of several compounds of formula (I) the average of the number of units represents,
R ^{2 is} independently or differently R ¹ or a group of the formula ABDQ, with the proviso that at least one R ^{2 is} different from R ¹ , wherein
A is an oxygen atom, a CH ₂ group or a CH = CH group, preferably an oxygen atom or a CH ₂ group,
B is a CH ₂ group or a divalent radical selected from linear or branched, saturated, mono- or polyunsaturated alkyl, aryl, alkylaryl or arylalkyl-oxy groups having 2 to 20 carbon atoms or a group of the formula -CH ₂ - O- (CH ₂ ) ₄ -O-,
D is a group of the general formula (II) - (C ₂ H ₄ O) _n (C ₃ H ₆ O) _o (C ₁₂ H ₂₄ O) _p (C ₈ H ₈ O) _q (C ₄ H ₈ O) _r - (II) is with
n, o, p, q and r are independent integers from 0 to 50, where the sum of the indices n + o + p + q + r is greater than or equal to 3 and the general formula II represents a random oligomer or a block oligomer, and
Q is a radical selected from hydrogen, linear or branched, saturated, mono- or polyunsaturated, alkyl, aryl, alkylaryl or arylalkyl groups having 1 to 20 carbon atoms, optionally containing one or more heteroatoms, optionally containing one or more carbonyl groups, optionally modified with an ionic organic group which may contain, for example, the heteroatoms sulfur, phosphorus and / or nitrogen.

As is apparent from the definition of the radical R ^2, the connection of the group R ² through a carbon atom (SiC linkage) or an oxygen atom (Si-O-linkage) can be carried out.

• a) Bereitstellen eines Si-H-Funktionen aufweisenden Polysiloxans. Dies kann z. B. durch Äquilibrieren einer Mischung enthaltend R¹ ₃SiO_1/2-Gruppen und R¹ ₂SiO_2/2-Gruppen haltige Siloxane und HSiR¹ ₂O_1/2-Gruppen und R¹ ₂SiO_2/2-Gruppen haltige Siloxane und gegebenenfalls Cyclosiloxane, wobei das molare Verhältnis von R¹ ₃SiO_1/2-Gruppen zu HSiR¹ ₂O_1/2-Gruppen von 1:30 bis 9:1, bevorzugt von 1:20 bis 6:1, besonders bevorzugt von 1:15 bis 5:1 und ganz besonders bevorzugt von 1:10 bis 2:1, beträgt (bzw. die Siloxane in einem Verhältnis eingesetzt werden, dass dieses Verhältnis vorliegt), erfolgen,
• b) Umsetzen der Äquilibriermischung mit einer Verbindung A'-B-D-Q mit A' = eine OH-Gruppe, eine Vinyl-Gruppe oder eine Ethinyl-Gruppe und R¹, B, D und Q wie oben definiert, wobei R¹ vorzugsweise ein Methylrest ist. Als Umsetzung in Verfahrensschritt b) kann z. B. eine Hydrosilylierungsreaktion oder eine dehydrogenativen Kondensation durchgeführt werden.

The organomodified polysiloxanes of the general formula (I) are preferably obtained by the process steps:

• a) providing a Si-H-functional polysiloxane. This can be z. B. containing by equilibrating a mixture of R ¹ ₃ SiO _1/2 groups, and R ¹ ₂ SiO _2/2 groups-containing siloxanes and HSiR ¹ ₂ O _1/2 groups, and R ¹ ₂ SiO _2/2 groups containing siloxanes and optionally cyclosiloxanes, wherein the molar ratio of R ¹ ₃ SiO _1/2 groups to HSiR ¹ ₂ O _1/2 groups from 1:30 to 9: 1, preferably from 1:20 to 6: 1, more preferably from From 1:15 to 5: 1 and most preferably from 1:10 to 2: 1 (or the siloxanes are used in a ratio such that this ratio is present),
• b) reacting the equilibration mixture with a compound A'-BDQ having A '= an OH group, a vinyl group or an ethynyl group and R ¹ , B, D and Q as defined above, wherein R ^{1 is} preferably a methyl radical , As an implementation in process step b) z. As a hydrosilylation reaction or a dehydrogenative condensation can be performed.

The provision of the Si-H-functional polysiloxane can be carried out in a manner known to those skilled in the art. The equilibration in process step a) can likewise be carried out in a manner known to the person skilled in the art, or as described in the prior art. Suitable methods for the equilibration of siloxanes are described, for example, in the patent EP 1439200 as in W. Noll, Chemistry and Technology of Silicones, Verlag Chemie, Weinheim, 2nd edition 1968, pages 187-197 described. The content of these documents is hereby incorporated by reference and is considered part of the disclosure of the present application.

In a preferred embodiment of the process according to the invention, a hydrosilylation reaction is carried out for the reaction in process step b). The compound A'-B-D-Q is thus linked via an Si-C bond with the siloxane.

Possible hydrosilylation, which can be used as process step b), z. In Bogdan Marciniec, "Comprehensive Handbook on Hydrosilylation", Pergamon Press 1992 ; Ivan Ojima, "The hydrosilylation reaction" in "The chemistry of organic silicon compounds" (editors S. Patai and Z. Rappoport), Wiley 1989 and in Ivan Ojima et al., "Recent advances in the hydrosilylation and related reactions" in "The chemistry of organic silicon compounds, Vol. 2" (Editors Z. Rappoport and Y. Apeloig), Wiley 1998 , which is expressly referred to and the content of which belongs to the disclosure content of the present application.

In a further preferred embodiment of the process according to the invention, a dehydrogenative condensation is used for the reaction in process step b). carried out. This can, for. B. be carried out so that the obtained in step a) SiH groups containing equilibrium mixture with hydroxy-functional organic compounds such as alcohols, condensing to release hydrogen gas. Such reactions are, for example, in the book "Silicone Chemistry and Technology", Vulkan-Verlag Essen, 1989, and in the writings EP 1 460 098 . DE 103 12 636 . DE 103 59 764 . DE 10 2005 051 939 and EP 1 627 892 as in JP 48-19941 , on the US 5,147,965 refers, described. The content of these documents is hereby incorporated by reference and is considered part of the disclosure of the present application. The alcohols used are preferably OH-terminated polyethers.

The molar ratio of reactive groups (OH groups in the case of dehydrogenative condensation, hydrosilylatable multiple bonds in the case of the hydrosilylation reaction) to silane hydrogen groups can be chosen as desired in process step b). Preferably, a molar ratio of 1: 1 to 2: 1, preferably from 1: 1 to 1.5: 1 is set.

The process according to the invention, in particular process steps a) and b), can be carried out in the presence of a solvent such as, for example, toluene, xylene or water or preferably without the presence of solvent. The process according to the invention, in particular process steps a) and / or b), can be carried out continuously or batchwise. In process steps a) and b), the reactants can be mixed together in any order.

wobei
M^w+ für ein w-wertiges Kation mit w = 1, 2, 3, oder 4 steht, und
R⁴ für Wasserstoff oder einen, aliphatischen Rest mit 1 bis 20 Kohlenstoffatomen steht,
R⁵ und R⁶ für gleiche oder verschiedene aliphatische Reste stehen,
G ein Sauerstoffatom, NH oder eine NR⁷ Gruppe ist, wobei R⁷ eine einwertige Alkylgruppe ist und
L einen zweiwertigen, verzweigten oder unverzweigten, gegebenenfalls Sauerstoff und/oder Stickstoff enthaltenden Alkylrest, darstellt.In a preferred embodiment of the present invention, the radical R ¹ in the general formula (I) is methyl, p = q = r = 0, the sum of the indices n + o is greater than or equal to 3 and Q is selected from the group comprising hydrogen and

in which
M ^{w + stands} for a w-valent cation with w = 1, 2, 3, or 4, and
R ^{4 is} hydrogen or an aliphatic radical having 1 to 20 carbon atoms,
R ⁵ and R ^{6 represent} identical or different aliphatic radicals,
G is an oxygen atom, NH or an NR ⁷ group, wherein R ^{7 is} a monovalent alkyl group and
L represents a divalent, branched or unbranched, optionally oxygen and / or nitrogen-containing alkyl radical.

In a further preferred embodiment of the present invention, the radical R ^{1 of} the general formula (I) is exclusively methyl, p = q = r = 0, the sum of the indices n + o is greater than or equal to 3, and Q is selected from Group comprising hydrogen, acetyl, methyl, ethyl, butyl and allyl radicals.

It is known to the person skilled in the art that the compounds are present in the form of a mixture with a distribution governed essentially by statistical laws. For example, in the composition may be a mixture of compounds of formula (I) with k = 1, 2, 3 and 4, etc. For the purposes of the invention, it has been found to be particularly advantageous if the compounds of the general formula (I) are used as a mixture. It can then be dispensed with a complex separation.

With the method according to the invention, both organomodified polysiloxanes of the formula (I) can be prepared in which the radicals R ² (with R ² = formula ABDQ) are bound exclusively to the terminal silicon atoms, exclusively to non-terminal silicon atoms or to terminal and non-terminal silicon atoms are bound.

It may be advantageous if the organomodified polysiloxanes obtained are mixtures of mono- and bifunctional compounds. Such mixtures preferably have as bifunctional polysiloxanes those of the formula (I) in which the radicals R ² (with R ² = formula ABDQ) are bonded exclusively to the two terminal silicon atoms.

The process according to the invention can be used to obtain the organomodified polysiloxanes according to the invention or compositions which contain these organomodified polysiloxanes.

The organomodified polysiloxanes according to the invention or the corresponding compositions comprising the organomodified polysiloxanes according to the invention can be prepared, for example, by Example, in the production of polyurethane foams or polyester polyurethane foams, as coating additives, as emulsifiers, as defoamers or in the production of hair and personal care products.

The preparation of the polyurethane foams can be carried out in a known manner. Preferably, one or more organic isocyanates having two or more isocyanate functions are reacted with one or more polyols having two or more isocyanate-reactive groups in the presence of one for the reactions Isocyanate polyol and / or isocyanate-water and / or the isocyanate trimerization active catalyst, water, optionally physical blowing agents, optionally flame retardants and optionally other additives implemented.

Suitable isocyanates for the purposes of this invention are preferably all polyfunctional organic isocyanates, such as, for example, 4,4'-diphenylmethane diisocyanate (MDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HMDI) and isophorone diisocyanate (IPDI). Particularly suitable is the mixture known as "polymeric MDI" ("crude MDI") of MDI and higher condensed analogues having an average functionality of 2 to 4, and the various isomers of TDI in pure form or as a mixture of isomers.

Suitable polyols for the purposes of this invention are preferably all organic substances having a plurality of isocyanate-reactive groups, as well as their preparations. Preferred polyols are all polyether polyols and polyester polyols customarily used for the preparation of polyurethane systems, in particular polyurethane foams. Polyether polyols are obtained by reacting polyhydric alcohols or amines with alkylene oxides. Polyester polyols are based on esters of polybasic carboxylic acids (which may be either aliphatic, for example adipic acid or aromatic, for example phthalic acid or terephthalic acid) with polyhydric alcohols (usually glycols). In addition, natural oils based on natural oils (natural oil based polyols, NOPs) can be used. These polyols are made from natural oils such. As soy or palm oil and can be used unmodified or modified.

A suitable ratio of isocyanate to polyol, expressed as the index of the formulation, is in the range of 10 to 1000, preferably 40 to 350. This index describes the ratio of actual isocyanate to isocyanate (calculated for a stoichiometric reaction with polyol). An index of 100 indicates a molar ratio of the reactive groups of 1 to 1.

Suitable catalysts for the purposes of this invention are substances which catalyze the gel reaction (isocyanate-polyol), the blowing reaction (isocyanate-water) or the di- or trimerization of the isocyanate. Typical examples are amines, such as. Triethylamine, dimethylcyclohexylamine, tetramethylethylenediamine, tetramethylhexanediamine, pentamethyldiethylenetriamine, pentamethyldipropylenetriamine, triethylenediamine, dimethylpiperazine, 1,2-dimethylimidazole, N-ethylmorpholine, tris (dimethylaminopropyl) hexahydro-1,3,5-triazine, dimethylaminoethanol, dimethylaminoethoxyethanol and bis (dimethylaminoethyl) ethers, tin compounds such as dibutyltin dilaurate and potassium salts such as potassium acetate. Preferably used as further catalysts are those which do not contain tin compounds, in particular no dibutyltin dilaurate.

Suitable amounts are dependent on the type of catalyst and are usually in the range of 0.01 to 5 pphp (= parts by weight based on 100 parts by weight of polyol) and 0.1 to 10 pphp for potassium salts.

Suitable water contents in the context of this invention depend on whether or not physical blowing agents are used in addition to the water. In the case of pure water-driven foams, the values are typically from 1 to 20 pphp, if other blowing agents are additionally used, the amount of use is reduced to usually 0 or 0.1 to 5 pphp. To obtain high foam chamber weights, neither water nor other blowing agents are used.

Suitable physical blowing agents for the purposes of this invention are gases, for example liquefied CO ₂ , and volatile liquids, for example hydrocarbons having 4 or 5 carbon atoms, preferably cyclo-, iso- and n-pentane, hydrofluorocarbons, preferably HFC 245fa, HFC 134a and HFC 365 mfc, chlorofluorocarbons, preferably HCFC 141b, oxygen-containing compounds such as methyl formate and dimethoxymethane, or chlorinated hydrocarbons, preferably dichloromethane and 1,2-dichloroethane. Furthermore, ketones (eg acetone) or aldehydes (eg methylal) are suitable as blowing agents.

In addition to water and optionally physical blowing agents, other chemical blowing agents can be used which react with isocyanates to gas evolution, such as formic acid or carbonates.

Suitable flame retardants in the context of this invention are preferably liquid organic phosphorus compounds, such as halogen-free organic phosphates, for. Triethyl phosphate (TEP), halogenated phosphates, e.g. Tris (1-chloro-2-propyl) phosphate (TCPP) and tris (2-chloroethyl) phosphate (TCEP) and organic phosphonates, e.g. Dimethylmethanephosphonate (DMMP), dimethylpropanephosphonate (DMPP), or solids such as Ammonium polyphosphate (APP) and red phosphorus. Furthermore, halogenated compounds, for example halogenated polyols, and solids such as expanded graphite and melamine are suitable as flame retardants.

The processing of the formulations into foams can be carried out by all methods familiar to the person skilled in the art, for example by hand mixing or preferably by means of high-pressure foaming machines. In this context, discontinuous processes, for example for the production of molded foams, refrigerators and panels, or continuous processes, for example in insulation boards, metal composite elements, blocks or in spray processes can be used.

Other additives which may be present in the composition used according to the invention include cell openers, dyes, UV stabilizers, substances for preventing microbial attack and further additives which are obvious to the person skilled in the art and are not listed here.

It is possible to use the polyesterpolyols, isocyanates, blowing agents, flame retardants, catalysts, additives and preparation processes known from the prior art. For example, those in the Scriptures EP 0 048 984 , which is hereby incorporated by reference, may be used.

In the use according to the invention, it is preferable to use as much of the organomodified polysiloxanes of the invention that the proportion of the organomodified polysiloxanes according to the invention, preferably those of the formula (I), of the mixture to be foamed is preferably from 0.05 to 1% by mass, preferably from 0.07 to 0.8 mass%, and more preferably from 0.1 to 0.5 mass%. The proportion of compounds of the formula (I) with exclusively terminal modification of the mixture to be foamed is preferably from 0 to 0.2% by mass, preferably from 0 to 0.1% by mass and more preferably from 0.01 to 0, 06 mass%. The proportion of the compound of formula (II) in the mixture to be foamed is preferably from 0 to 0.15 mass%, preferably from 0.001 to 0.1 mass% and particularly preferably from 0.002 to 0.05 mass%.

In the examples given below, the present invention is described by way of example, without the invention, the scope of application of which is apparent from the entire description and the claims, to be limited to the embodiments mentioned in the examples.

Examples:

Example 1: Process according to the invention

To 1000 kg of an organomodified siloxane, which had clearly visible turbidity and by reacting an allyl alcohol started polyether (polyethylene oxide) with a SiH-containing hydrogen siloxane in an analogous to Example 1 of EP 1520870 obtained as polyether and hydrogen siloxane in Example 5 of EP 1520870 materials described used) was added with stirring 1 wt .-%, based available from Evonik Degussa GmbH, placed on the organomodified siloxane to Sipernat ^® D17, a hydrophobic silica. After a stirring time of 15 minutes, the mixture was filtered using a frame filter press with paper filter plates.

The resulting filtrate no longer showed turbidity visible to the naked eye. The performance of the product as a PU foam stabilizer showed that it met the specifications.

Example 2: process not according to the invention

The experiment of Example 1 was repeated except that no hydrophobic silica was added to the mixture prior to filtration.

The resulting filtrate had no difference in turbidity compared to the unfiltered product.

The examples clearly show that by contacting the product mixture with particles having a hydrophobic surface and then removing the particles, the haze can be removed from the product mixture.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 0048984 [0003, 0052]
• DE 102007046736 [0004]
• JP 08-319352 [0007]
• EP 1281735 [0019]
• EP 1439200 [0027]
• EP 1460098 [0030]
• DE 10312636 [0030]
• DE 10359764 [0030]
• DE 102005051939 [0030]
• EP 1627892 [0030]
• JP 48-19941 [0030]
• US 5147965 [0030]
• EP 1520870 [0055, 0055]

Cited non-patent literature

• ASTM C 690 - 1992 [0017]
• ISO 5794-1 [0018]
• J. Chojnowski, M. Cypryk, Synthesis of Linear Polysiloxane, Chapter 1 in RG Jones et al., Silicone Containing Polymers, Kluwer, 2000. [0023]
• W. Noll, Chemistry and Technology of the Silicones, Verlag Chemie, Weinheim, 2nd edition 1968, pages 187-197 [0027]
• Bogdan Marciniec, "Comprehensive Handbook on Hydrosilylation", Pergamon Press 1992 [0029]
• Ivan Ojima, "The Hydrosilylation Reaction" in "The Chemistry of Organic Silicon Compounds" (Editors S. Patai and Z. Rappoport), Wiley 1989 [0029]
• Ivan Ojima et al., "Recent advances in the hydrosilylation and related reactions" in "The chemistry of organic silicon compounds, Vol. 2" (Editors Z. Rappoport and Y. Apeloig), Wiley 1998. [0029]

Claims (15)

Process for the preparation of organomodified polysiloxanes by linking siloxanes having Si-H bonds with organic compounds containing OH groups or CC multiple bonds, characterized in that the reaction mixture obtained in the linking reaction is brought into contact with particles which have a hydrophobic surface and the particles are then removed from the reaction mixture again. A method according to claim 1, characterized in that the removal of the particles by filtration, decantation, settling, sedimentation or centrifugation takes place. A method according to claim 1 or 2, characterized in that the particles are selected from plastic particles and from particles of metal or Halbmetalloxiden, -hydroxiden or carbonates, organic silicones, silicates, clays and celluloses. Method according to at least one of Claims 1 to 3, characterized in that the particles have an average particle size d ₅₀ of <50 μm, a specific surface area of> 25 m ² / g and a methanol wettability of more than 10%. A method according to claim 4, characterized in that the particles have a mean particle size d ₅₀ of> 1 to <20 microns, a specific surface area of 75 to 200 m ² / g and a methanol wettability of greater than 50. Method according to at least one of claims 1 to 5, characterized in that the mass of particles which are added to the reaction mixture, from 0.1 to 10 mass, based on the reaction mixture. Process according to at least one of Claims 1 to 6, characterized in that the process comprises an equilibration step which is linked before or after the linking step in which siloxanes containing Si-H bonds are linked to OH groups or C-C multiple bonds organic compounds, is carried out. Process according to at least one of Claims 1 to 7, characterized in compounds of the general formula (I)

where R ^{1 is} identical or different, straight-chain or branched, aliphatic or aromatic, optionally halogenated, optionally unsaturated hydrocarbon radicals having 1 to 8 carbon atoms, k = 0 to 200, R ² R ¹ or a group of the formula ABDQ, with the proviso in numerical average at least one R ^{2 is} other than R ¹ , wherein A is an oxygen atom, a CH ₂ group or a CH = CH group, B is a CH ₂ group or a bivalent radical selected from linear or branched, saturated , mono- or polyunsaturated alkyl, aryl, alkylaryl or arylalkyl-oxy groups having 2 to 20 carbon atoms or a group of the formula -CH ₂ -O- (CH ₂ ) ₄ -O-, D is a group of the general formula (II) - (C ₂ H ₄ O) _n (C ₃ H ₆ O) _o (C ₁₂ H ₂₄ O) _p (C ₈ H ₈ O) _q (C ₉ H ₈ O) _r - (II) is, with n, o, p, q and r independent integers from 0 to 50, wherein the sum of the indices n + o + p + q + r is greater than or equal to 3 and the general formula II is a random oligomer or a Represents a block oligomer, and Q is a radical selected from hydrogen, linear or branched, saturated, mono- or polyunsaturated, alkyl, aryl, alkylaryl or arylalkyl groups having 1 to 20 carbon atoms, optionally one or containing a plurality of heteroatoms, optionally containing one or more carbonyl groups, optionally modified with an ionic organic group. A method according to claim 8, characterized in that the method steps a) equilibrating a mixture comprising R ¹ ₃ SiO _1/2 groups, and R ¹ ₂ SiO _2/2 groups-containing siloxanes and HSiR ¹ ₂ O _1/2 groups, and R ¹ ₂ SiO _2/2 group-containing siloxanes and optionally cyclosiloxanes, wherein the molar ratio of R ¹ ₃ SiO _1/2 groups to HSiR ¹ ₂ O _1/2 groups of 1: 4 to 9: 1, b ) Reacting the equilibration mixture with a compound A'-BDQ having A '= an OH group, a vinyl group or an ethynyl group and B, D and Q as defined in claim 7. A method according to claim 8 or 9, characterized in that the radical R ^{1 of} the general formula (I) is methyl, p = q = r = 0, the sum of the indices n + o is greater than or equal to 3 and Q is selected from the group comprising hydrogen and

wherein M ^{w + is} a w-valent cation with w = 1, 2, 3, or 4, and R ^{4 is} hydrogen or an aliphatic radical having 1 to 20 carbon atoms, R ⁵ and R ^{6 are the} same or different aliphatic radicals G is an oxygen atom, NH or an NR ⁷ group, wherein R ^{7 is} a monovalent alkyl group and L is a divalent, branched or unbranched, optionally oxygen and / or nitrogen-containing alkyl radical. Method according to at least one of claims 1 to 10, characterized in that the radical R ^{1 of} the general formula (I) stands exclusively for methyl groups, p = q = r = 0, the sum of the indices n + o is greater than or equal to 3 , and Q is selected from the group comprising hydrogen, acetyl, methyl, ethyl, butyl and allyl radicals. Organomodified polysiloxanes obtainable by a process according to at least one of claims 1 to 11. Composition comprising organomodified polysiloxanes obtainable by a process according to at least one of Claims 1 to 11. Use of organomodified polysiloxanes according to Claim 12 or compositions containing organomodified polysiloxanes according to Claim 13 in the production of polyurethane foams or polyester polyurethane foams, as emulsifiers, as coating additives, as defoamers or in the manufacture of hair and personal care products. Use according to claim 14, characterized in that the proportion of organomodified polysiloxanes in the mixture to be foamed is from 0.05 to 1% by mass.