Subdivided particle-stabilized aqueous pickering emulsions and particles made therefrom

Abstract

The present invention relates to a process for the preparation of a particle-stabilized aqueous Pickering emulsion (E) of a material (S) suitable for addition, condensation or chain polymerization and selected from the group consisting of siloxanes and silanes, in which process an aqueous phase (W), a material (S) suitable for addition, condensation or chain polymerization and selected from the group consisting of siloxanes and silanes, and a particulate solid (F) are mixed to form droplets with an average diameter d 50 of at most 9 pm and comprising said material (S) and said particulate solid (F), with the proviso that the mass ratio Q1 = m(F) / m(S)*100 is any value from 3 to 25, the mass ratio Q2 = m(S) / (m(S)+m(W))*100 is any value from 50 to 75, and the relationship between Q1 and Q2 is Q2 = -(1.56*Q1) + Q3, wherein Q3 is a value between 77.0 and 89.0, in a particle-stabilized Pickering emulsion. The present invention also relates to a process for the production of particles (P) and to condensed crosslinked or polymerized crosslinked particles (P).

Description

[0001] This invention relates to a particle-stabilized aqueous Pickering emulsion suitable for addition polymerization, condensation polymerization or chain polymerization, a method for producing said emulsion, a method for producing particles from said Pickering emulsion, and the particles.

[0002] WO2017142068A1 discloses a finely divided silica-stabilized emulsion of reactive addition-crosslinked siloxanes, but the drawback is the use of a very large amount of silica. The core of the silicone elastomer particles is formed through an addition polymerization reaction.

[0003] WO2007113095 also describes the production of silicone particles via silica-stabilized emulsions. It teaches that particle size can be controlled by emulsification techniques (in other words, by variables such as the introduced shear energy, the volume fraction of the dispersed silicon-organic phase, the amount of stabilized fine metal oxide particles, the pH and ionic strength of the continuous aqueous phase, viscosity, the order of stoichiometric addition, and the stoichiometric addition rate) or by the reaction scheme (in other words, by reaction temperature, reaction time, and the concentration of the raw materials used). The choice and amount of optional hydrolysis and condensation catalysts also affect particle size.

[0004] WO2007113095 further teaches that when using emulsification techniques that allow for the production of relatively small droplets, this method produces small, surface-structured particles. For this purpose, different shear energies or different amphiphilic particles can be used, for example, to stabilize condensable liquids or formulations in water.

[0005] The subject of this invention is a method for preparing a partically stable aqueous Pickerling emulsion (E) of a material (S) selected from siloxanes and silanes, suitable for addition polymerization, condensation polymerization or chain polymerization:

[0006] By mixing aqueous phase (W),

[0007] Materials (S) suitable for addition polymerization, condensation polymerization, or chain polymerization and selected from siloxanes and silanes, and

[0008] Particulate solids (F),

[0009] Forming an average diameter d 50 For droplets up to 9 μm in size comprising both material (S) and particulate solids (F), the conditions are: in a partically stable Pickering emulsion.

[0010] The mass ratio Q1 = m(F) / m(S) * 100 is any value from 3 to 25.

[0011] The mass ratio Q2 = m(S) / (m(S) + m(W)) * 100 is any value from 50 to 75, and

[0012] The relationship between Q1 and Q2 is:

[0013] Q2 = -(1.56*Q1) + Q3, where

[0014] Q3 is a value between 77.0 and 89.0.

[0015] Surprisingly, when the above mass ratio was observed, a finely divided, particle-stabilized aqueous Pickering emulsion (E) was formed. This finely divided emulsion (E) can only be obtained by using an additional organic emulsifier, which would cause damage by adhering to the droplets.

[0016] Average diameter d 50 Droplet sizes smaller than 9 μm are largely independent of the mixing method and mixing energy in the method of this invention. This makes the method of this invention substantially more robust and allows for variations in batch size or mixing methods (such as operational scale-up) without requiring expensive and inconvenient formulation or method adjustments.

[0017] Compared to existing coarse-particle emulsions that do not conform to the present invention, Pickering emulsions (E) have the advantage of exhibiting improved separation stability, which means that they are largely stable to the emulsification or sedimentation of the dispersed phase.

[0018] Pickering emulsion E preferably showed no significant separation within 21 days of storage at room temperature.

[0019] Another advantage of Pickering emulsions (E) is their low shear viscosity, making them easy to apply. Furthermore, the aqueous emulsions of this invention have the advantage of high storage stability for at least 15 months in a closed system at room temperature.

[0020] Another advantage of Pickering emulsion (E) is that it eliminates the need for organic emulsifiers, thus significantly improving, among other benefits, the water resistance of the resulting molded article's interface with the substrate and its adhesion to the substrate. Because organic emulsifiers are omitted, the particles P produced from Pickering emulsion (E) contain no organic emulsifiers. This is a significant advantage for cosmetic applications, where such contaminants degrade product quality or are practically undesirable.

[0021] The method of the present invention for producing Pickering emulsions (E) offers the advantage of producing finely divided emulsions without the need for very large amounts of excess stabilizing particles. As a result, non-reactive contaminants that could enter the environment and adversely affect the activity of crosslinkable emulsions are avoided in the Pickering emulsions (E).

[0022] The advantage of Pickering emulsions (E) is that their rheology can be tuned within the known range of non-aqueous systems compared to existing systems.

[0023] Another advantage of Pickering emulsion (E) is that the mechanical properties of the fully cured product are within the range known for non-aqueous systems.

[0024] In addition, Pickering emulsions (E) have the advantage that they can be formulated so that no volatile organic compounds are released into the atmosphere during the curing process.

[0025] Furthermore, Pickering emulsions (E) have the advantage of forming a strong-adhesion coating on many substrates, such as paper, fabrics, mineral building materials like fiber cement, plastics, wood, and many other substrates. Therefore, they are also suitable for adhesively bonding many substrates. The coating can be applied, for example, by brushing, rolling, dipping, or spraying.

[0026] The Pickering emulsion (E) of crosslinkable organopolysiloxanes has advantages over coarse particulate emulsions not according to the invention: the reactive organopolysiloxanes, due to their smaller droplet size, can penetrate deeper into the material being treated during coating, impregnation, and hydrophobication processes, thereby improving the activity and durability of the surface treatment. As used in the prior art, very high excesses of particulate emulsifiers can clog the pores of the material being treated and deposit on the surface. This reduces the activity of the application. The method of the present invention for producing the Pickering emulsion (E) enables the production of finely divided emulsions without using large excesses of particulate emulsifiers. If the kind of organic emulsifiers used in the prior art are used, they will deposit on the surface. This can lead to adverse effects—for example, the organic emulsifiers can impair the printability of the surface and adhesion during bonding.

[0027] Another subject of the present invention is a particulate-stable aqueous Pickering emulsion (E) that can be produced by the above method.

[0028] Droplets containing material (S) and particulate solids (F) form a discontinuous phase of Pickering emulsion (E).

[0029] The discontinuous phase preferably comprises materials suitable for addition polymerization, condensation polymerization or chain polymerization and contains at least one or more siloxanes or silanes.

[0030] Preferably, the material (S) is: at least one siloxane suitable for addition polymerization, condensation polymerization or chain polymerization and having the general formula (IV).

[0031] [A 1 mR 9 pSiO(4-pm) / 2](IV),

[0032] in

[0033] A 1It is either hydrogen or a hydrocarbon group containing up to 30 carbon atoms and may also contain heteroatoms selected from O, S, Si, Cl, F, Br, P, or N atoms, therefore A 1 It can also be a functional group that has not been replaced or has been replaced.

[0034] R 9 This refers to an alkoxy or aryloxy group having a maximum of 18 carbon atoms, or a hydroxyl group or H, or a group that can be independent of A. 1 It has its definition

[0035] m and p represent the values ​​0, 1, 2, or 3, respectively.

[0036] Or at least one silane suitable for addition polymerization, condensation polymerization or chain polymerization and having the general formula (V)

[0037] (R 10 ) 4-n -Si-(OR 11 ) o (V),

[0038] Where o is a numerical value of 1, 2, 3, or 4.

[0039] R 10 The term indicates a straight-chain or branched alkyl group having 1 to 16 carbon atoms, wherein non-adjacent carbon atoms may be substituted with oxygen atoms, or indicates an aryl group, or an organic functional group selected from the following: phosphonic acid monoester group, phosphonic acid diester group, phosphonic acid group, methacryloyloxy, acryloyloxy, vinyl, mercapto, isocyanate group (wherein the isocyanate group may optionally be reaction-blocked to prevent chemical reaction), hydroxyl, hydroxyalkyl, vinyl, epoxy, glycidoxy, morpholino, piperazine, primary, secondary, or tertiary amino group having one or more nitrogen atoms (wherein the nitrogen atom may be substituted with hydrogen or a monovalent aromatic, aliphatic, or cycloaliphatic hydrocarbon group), carboxylic acid group, carboxylic anhydride group, aldehyde group, urethane group, urea group, wherein the group R 10 It can be directly bonded to silicon atoms or separated from them by carbon chains of 1-6 carbon atoms, and

[0040] R 11 It is a monovalent, straight-chain or branched aliphatic or alicyclic hydrocarbon group, wherein non-adjacent carbon atoms can be substituted by heteroatoms such as O, N, P, S, Cl, F, Br, or Si, wherein the free valence of the relevant heteroatoms can be saturated by straight-chain or branched alkyl groups or hydrogen atoms, or a monovalent aromatic group or in the form -C(=O)-R. 12 The group, wherein R 12 It is a monovalent straight-chain or branched aliphatic or cycloaliphatic hydrocarbon group or a monovalent aromatic hydrocarbon group, wherein the selected silane or optionally selected silane may exist in a non-hydrolyzed form, a hydrolyzed form, or a hydrolyzed and partially condensed form, or a mixture of these forms.

[0041] Or formulations of two or more such general formula (IV) siloxanes and / or general formula (V) silanes.

[0042] The silane, siloxane, or formulation is preferably a silane, siloxane, or formulation suitable for condensation or addition polymerization, and is particularly preferred to be a silane, siloxane, or formulation suitable for addition polymerization.

[0043] Silanes, siloxanes, or formulations suitable for addition polymerization, condensation polymerization, or chain polymerization are preferably liquids at room temperature and ambient atmospheric pressure (in other words, 10¹³ hPa), and preferably have a molecular weight of 1 to 500,000 mm. 2 / s, more preferably 10 to 100,000 mm 2 / s, highly preferred 50 to 50,000 mm 2 / s, with a preferred size of 100 to 10000 mm 2 Viscosity per second.

[0044] In a preferred embodiment, a formulation is used consisting of at least one vinyl-containing organopolysiloxane and at least one organopolysiloxane having silicon-bonded hydrogen atoms, the formulation having a 150 mm² content at 25°C. 2 / s to 8000mm 2 Viscosity per second.

[0045] In a particularly preferred embodiment, a formulation is used comprising at least one vinyl-containing organopolysiloxane, at least one vinyl-containing organopolysiloxane resin, and at least one organopolysiloxane having silicon-bonded hydrogen atoms, the formulation having a 500 mm² content at 25°C. 2 / s to 5000mm 2 Viscosity per second.

[0046] The material (S) preferably comprises one or more siloxanes consisting of repeating units of general formula (IV) and / or silanes of general formula (V).

[0047] Although not specified in general formula (IV), up to 10 mol% of the diorganosiloxane unit can be replaced by other siloxane units; however, these other siloxane units are usually present only as more or less unavoidable impurities, such as R3SiO 1 / 2 ,RSiO 3 / 2 and SiO 4 / 2 Unit, wherein R has the definition indicated above for A1.

[0048] The particulate solids (F) used in this invention preferably include particles that are solid at room temperature and ambient atmospheric pressure (in other words, 1013 hPa).

[0049] At ambient atmospheric pressure (in other words, 1013 hPa), the particulate solid (F) preferably has a solubility in water of less than 0.1 g / L, more preferably less than 0.05 g / L, at a pH of 7.33 and an electrolyte background of 0.11 mol and a temperature of 37°C.

[0050] The particulate solid (F) preferably has a molar mass greater than 10,000 g / mol, more preferably 50,000 to 50,000,000 g / mol, and more particularly 100,000 to 10,000,000 g / mol, wherein the molar mass is preferably determined by static light scattering in each case.

[0051] The particulate solid (F) preferably has a particle size of 30 to 500 μm. 2 / g, more preferably 100 to 300m 2 / g BET specific surface area. BET surface area is measured by known methods, preferably according to German industrial standards DIN 66131 and DIN 66132.

[0052] The particulate solid (F) has a Mohs hardness preferably greater than 1, more preferably greater than 4.

[0053] The particulate solid (F) used is preferably a metal oxide having a covalent bond component in the metal-oxygen bond, examples of solid oxides of main group elements and transition elements, such as solid oxides of group 3 elements, such as oxides of boron, aluminum, gallium and indium, solid oxides of group 4 elements, such as silicon dioxide, germanium dioxide and tin oxide and tin dioxide, lead oxide and lead dioxide, or oxides of transition elements, such as titanium dioxide, zirconium dioxide, hafnium dioxide, cerium oxide or iron oxide.

[0054] The metal oxides used in this invention are preferably aluminum (III) oxides, titanium (IV) oxides and silicon (IV) oxides, such as silica or silica produced by wet chemical methods—e.g., precipitated silica, or alumina, titanium dioxide or silica produced in high-temperature operation, such as alumina, titanium dioxide or silica produced by pyrolysis, with pyrolytic silica being particularly preferred.

[0055] The preferred pyrolytic silica is silanized pyrolytic silica with a methanol value of less than 70.

[0056] Partially water-wettable metal oxides as described in EP 1433749 A1 and DE 10349082 A1 are highly preferred.

[0057] Here, the average particle size of the particulate solid (F) or, where appropriate, the aggregate of particles is preferably smaller than the average diameter d of the droplet without subdivided particles. 50 .

[0058] The average particle size of the particulate solid (F) is less than 1000 nm, preferably between 10 nm and 800 nm, more preferably between 50 nm and 500 nm, and very preferably between 75 nm and 300 nm. The average particle size is measured in each case as the average hydrodynamic equivalent diameter using photon correlation spectroscopy with 173° backscattering from a Nanosizer ZS from Malvern. The methanol number of the particulate solid (F) is preferably less than 70, more preferably less than 50, very preferably less than 40, and particularly preferably less than 30.

[0059] The methanol value is determined by preparing defined mixtures of water and methanol and then measuring the surface tension of these mixtures using known techniques. In separate experiments, these water-methanol mixtures are covered with a defined amount of particles and shaken under defined conditions (e.g., gently shaken by hand or through a drum mixer for about 1 minute). Measurements are taken for water-methanol mixtures where the particles just barely sink, and for water-methanol mixtures with a higher alcohol content where the particles just sink. The surface tension of the latter alcohol-water mixture generates the critical surface energy γ. crit γ is a measure of the surface energy of particles. The methanol content in water gives the methanol value.

[0060] The carbon content of the particulate solid (F) is greater than 0% by weight, preferably 0.1-4% by weight, more preferably 0.25-3.5% by weight, and very preferably 0.5-3% by weight, said carbon content being measured by elemental analysis of the dried particulate solid.

[0061] With respect to at least one siloxane or silane, the droplet may additionally contain, for example, a catalyst, filler, inhibitor, heat stabilizer, solvent, plasticizer, color pigment, sensitizer, photoinitiator, adhesion promoter, thixotropic agent, conductive additive, cosmetic substance, fragrance, active pharmaceutical or cosmetic ingredient, and silicone resin.

[0062] The particulate stable Pickerling emulsion (E) of the present invention is preferably substantially free of conventional liquid and solid organic surfactants that are non-particulate at room temperature and ambient atmospheric pressure, such as nonionic, cationic and anionic emulsifiers (“organic emulsifiers”).

[0063] The term "organic emulsifier" here does not refer to particles and colloids, but rather to molecules and polymers that conform to the definitions of molecules, polymers, colloids, and particles given in Dispersionen und Emulsionen [Dispersions and Emulsions], G. Lagaly, O. Schulz, R. Zindel, Steinkopff, Darmstadt 1997, ISBN 3-7985-1087-3, pp. 1-4.

[0064] Typically, these organic emulsifiers have a size of less than 1 nm, a molar mass of <10,000 g / mol, a carbon content of >50% by weight that can be determined by elemental analysis, and a Mohs hardness of less than 1.

[0065] Meanwhile, the emulsions of the present invention, which are substantially free of organic emulsifiers, typically have a solubility of more than 1% by weight in water at 20°C and ambient atmospheric pressure (in other words, 1013 hPa) in a homogeneous or micellar form.

[0066] The emulsion (E) of the present invention may contain such organic emulsifiers at a maximum concentration of less than 0.1 times, preferably less than 0.01 times, more preferably less than 0.001 times, and more particularly less than 0.0001 times the critical micelle concentration of these organic emulsifiers in the aqueous phase; this corresponds to a concentration of these organic emulsifiers of less than 10% by weight, preferably less than 2% by weight, more preferably less than 1% by weight, and more particularly 0% by weight of the total weight of the dispersion based on the present invention.

[0067] Preferably, a primary dispersion (V) of particulate solid (F) in an aqueous phase (W) is prepared before mixing with the material (S).

[0068] Primary dispersions (V) can in principle be prepared according to known methods for preparing particulate dispersions, such as by incorporation with stirring elements having a high shear effect, such as high-speed stirrers, high-speed dissolvers, rotor-stator systems, ultrasonic dispersers, or ball mills or bead mills.

[0069] In this case, the concentration of solids (F) in the primary dispersion (V) is between 1 and 80% by weight, preferably between 10 and 60% by weight, more preferably between 10 and 40% by weight, and very preferably between 12 and 30% by weight.

[0070] Particle-stabilized Pickering emulsions (E) can be produced using any technology known to those skilled in the art for producing emulsions. However, it has been found that particularly suitable emulsions can be obtained by the following methods:

[0071] Method 1:

[0072] - Initially introduce a highly concentrated primary dispersion (V) with an initial volume such that it contains the total amount of the desired fine solids (F) and only a portion of the aqueous phase (W).

[0073] - In the case of continuous homogenization by means of, for example, a high-speed mixer, a high-speed dissolver or a rotor-stator system, the total volume of material (S) is slowly metered in.

[0074] -Optionally, in the case of continuous homogenization by, for example, a high-speed stirrer, a high-speed dissolver or a rotor-stator system, the required remaining volume of aqueous phase (W) is then slowly metered in.

[0075] Method 2:

[0076] -Initially introduce the total volume of material (S).

[0077] - In the case of continuous homogenization by means of, for example, a high-speed stirrer, a high-speed dissolver or a rotor-stator system, a highly concentrated primary dispersion (V) is slowly metered in, the metered volume of which contains the total amount of the desired particulate solids (F) and only a portion of the aqueous phase (W).

[0078] -Optionally, in the case of continuous homogenization by, for example, a high-speed stirrer, a high-speed dissolver or a rotor-stator system, the required remaining volume of aqueous phase (W) is then slowly metered in.

[0079] Method 3:

[0080] -Initially introduce the total volume of material (S).

[0081] - In the case of continuous homogenization by means of, for example, a high-speed stirrer, a high-speed dissolver or a rotor-stator system, a primary dispersion (V) is slowly metered in, the metered volume of which contains the total amount of the desired solids (F) and aqueous phase (W).

[0082] Method 4:

[0083] - Initially introduce a primary dispersion (V) with an initial volume such that it contains the total amount of the desired solids (F) and aqueous phase (W).

[0084] - In the case of continuous homogenization by means of, for example, a high-speed mixer, a high-speed dissolver, a rotor-stator system or a capillary emulsifier, the total volume of material (S) is slowly metered in.

[0085] Method 5:

[0086] - The initial volume of material (S) and primary dispersion (V) is introduced, the initial volume of which contains the total amount of desired particulate solids (F) and aqueous phase (W).

[0087] - Combined homogenization is achieved through, for example, a high-speed stirrer, a high-speed dissolver, or a rotor-stator system. Method 6:

[0088] - The initial volume of the material (S) and the highly concentrated primary dispersion (V) are introduced, the initial volume of which contains the total solids (F) and aqueous phase (W).

[0089] - Combined homogenization is achieved through, for example, a high-speed mixer, a high-speed dissolver, or a rotor-stator system.

[0090] -Optionally, in the case of continuous homogenization by, for example, a high-speed stirrer, a high-speed dissolver or a rotor-stator system, the required remaining volume of aqueous phase (W) is then slowly metered in.

[0091] Methods 1, 4, 5 and 6 are preferred, with methods 4 and 5 being particularly preferred, and method 5 being especially preferred.

[0092] Homogenization is preferably performed in at least one method step for at least 30 seconds, preferably at least 1 minute.

[0093] In an optional method step, the particulate-stabilized Pickering emulsion (E) of the present invention may be diluted with an aqueous phase (W) while continuous homogenization is performed, for example by a high-speed stirrer, a high-speed dissolver, or a rotor-stator system.

[0094] The described method can be performed in a continuous or discontinuous manner. The continuous manner is preferred.

[0095] The temperature during the emulsification process is between 0°C and 80°C, preferably between 10°C and 50°C, and more preferably between 20°C and 40°C.

[0096] Emulsification can be performed at atmospheric pressure (in other words, at 1013 hPa), at elevated pressure, or at reduced pressure. Operation at atmospheric pressure is preferred.

[0097] For the emulsion (E), the particulate solids (F), the material (S), and the aqueous phase (W) are preferably mixed in the following proportions:

[0098] (F): Preferably 2-15% by weight, more preferably 3-13% by weight, very preferably 4-12% by weight

[0099] (S): Preferably 50-70% by weight, more preferably 53-68% by weight, very preferably 55-65% by weight

[0100] (W): Preferably 23-45% by weight, more preferably 25-40% by weight, very preferably 27-36% by weight

[0101] Q1 is preferably any value from 5 to 22, more preferably from 8 to 18, and more particularly from 10 to 16.

[0102] Q2 is preferably any value from 55 to 70, more preferably from 60 to 70.

[0103] Q3 is preferably any value from 77 to 89, more preferably from 82 to 88, and even more particularly from 84 to 87.

[0104] After mixing, emulsion E can be diluted with any amount of water as needed.

[0105] The mixing in this method is preferably carried out for less than 120 hours, more preferably between 0 and 48 hours, very preferably between 0.1 and 24 hours, and in one specific embodiment, between 0.25 and 12 hours.

[0106] In this method, in addition to the aqueous phase (W), material (S), and solid (F), a catalyst as described above for accelerating and completing crosslinking may optionally be added. This addition may be made before the generation of the Pickering emulsion (E), directly added to the material (S) or the aqueous phase (W), during mixing, or subsequently added to the completed Pickering emulsion.

[0107] The amount of any added catalyst is within the typical quantitative range for catalysts.

[0108] The reaction temperature during mixing is between 0°C and 150°C, preferably between 10°C and 80°C, and more preferably between 15°C and 60°C.

[0109] The process can optionally be carried out in an inert gas atmosphere such as nitrogen, argon, or carbon dioxide. In that case, the oxygen fraction is less than 15% by volume, preferably less than 10% by volume, and more preferably less than 5% by volume.

[0110] The pH of the emulsion (E) is between pH 10 and 1, preferably between pH 9 and 2, more preferably between pH 7 and 2, and in one specific embodiment, between pH 6 and 2.5.

[0111] The emulsion (E) may optionally be mixed with water-soluble organic solvents such as alcohols (e.g., methanol, ethanol, or isopropanol), ketones (e.g., acetone or MEK), ethers (e.g., THF), or others. These may be added directly after the production of the emulsion (E) is completed, or during mixing.

[0112] The emulsion (E) can optionally be mixed with dispersing agents, protective colloids, etc. These can be added directly after the production of the emulsion (E) is completed, or during mixing.

[0113] The emulsion (E) preferably contains less than 5% by weight of dispersing aids, protective colloids, etc.; the particulate dispersion of the present invention more preferably contains less than 1% by weight of dispersing aids, protective colloids, etc.; very preferably, the particulate dispersion of the present invention contains less than 0.1% by weight of dispersing aids, protective colloids, etc., and in one specific embodiment, the emulsion (E) does not contain dispersing aids, protective colloids, etc.

[0114] Organic or inorganic electrolytes may optionally be added to the emulsion (E). They may be added after the Pickering emulsion production is completed, during the reaction phase, or directly after the reaction phase. In this case, the ionic strength of the dispersion is between 0.01 mmol / L and 1 mol / L, preferably between 0.1 mmol / L and 500 mmol / L, and very preferably between 0.5 mmol / L and 100 mmol / L.

[0115] Thickeners may optionally be added to the emulsion (E). These may be organic or inorganic thickeners, which are present in solid or liquid form at room temperature and ambient atmospheric pressure (in other words, at 1013 hPa). They may be added directly after the production of the emulsion (E) is completed, or during mixing.

[0116] Prior to emulsification of the emulsion (E), fillers may optionally be added to the component (S), preferably in an amount of 0.1 to 200 parts by weight, more preferably 0.5 to 100 parts by weight, based on 100 parts by weight of material (S) in each case. The amount of filler used can vary over a wide range and is particularly guided by the corresponding application of the emulsion (E) of the present invention.

[0117] Fillers and adjuvants may be added before the production of the Pickerling emulsion (E), directly to the material (S) or aqueous phase (W), during emulsification, or subsequently to the finished Pickerling emulsion.

[0118] Examples of fillers are non-reinforced fillers, such as those with a thickness up to 50m. 2 Fillers with a BET surface area of ​​ / g, such as quartz, diatomaceous earth, calcium silicate, zirconium silicate, zeolite, alumina, titanium oxide, iron oxide, zinc oxide, barium sulfate, calcium carbonate, gypsum, silicon nitride, silicon carbide, boron nitride, glass powder, and plastic powder.

[0119] Examples of reinforcing fillers are the fillers described above for particulate solids (F) and having a BET specific surface area of ​​30 to 500 m² / g, as well as silicone resins.

[0120] Examples of silicone resin F are MQ, MT, T, MDQ, MDT, MTQ, and MDTQ silicone resins, where M is selected from R3SiO. 1 / 2 and HR2SiO 1 / 2 and R 1R2SiO 1 / 2 Unit, D is selected from R 1 RSiO 1 / 2 and R2SiO 1 / 2 and HRSiO 1 / 2 Unit, T is selected from RSiO 3 / 2 and R 1 SiO 3 / 2 and HSiO 3 / 2 unit, and Q represents SiO 4 / 2 Units, wherein R, in each occurrence, is independently identical or different an organic or inorganic group that does not contain aliphatic carbon-carbon multiple bonds, and R 1 Each time it appears, it is independently identical or different from a hydrocarbon group having at least one monovalent, substituted or unsubstituted SiC bonded aliphatic carbon-carbon multibond.

[0121] Group R preferably comprises a SiC-bonded, optionally substituted hydrocarbon group that does not have an aliphatic carbon-carbon multi-bond and has a monovalent carbon atom of 1 to 18, more preferably comprises a SiC-bonded hydrocarbon group that does not have an aliphatic carbon-carbon multi-bond and has a monovalent carbon atom of 1 to 6, and more particularly comprises methyl or phenyl.

[0122] Group R 1 It may contain any desired group suitable for addition reactions (hydrosilylation) with SiH-functional compounds.

[0123] Group R 1 Preferably, it comprises alkenyl and ynyl groups having 2 to 16 carbon atoms, such as vinyl, allyl, methylallyl, 1-propenyl, 5-hexenyl, ethynyl, butadienyl, hexadienyl, cyclopentenyl, cyclopentadienyl, cyclohexenyl, vinylcyclohexylethyl, divinylcyclohexylethyl, norbornel, vinylphenyl, and styryl, with vinyl, allyl, and hexenyl being particularly preferred.

[0124] Silicone resins suitable as fillers are solid at 20°C and 1013 hPa.

[0125] The droplets of the present invention in an emulsion (E) composed of the sum of the materials used (S) and particulate solids (F). part Between 0.1% by weight and 99% by weight, preferably between 5% by weight and 90% by weight, more preferably between 10% by weight and 80% by weight.

[0126] The completed emulsion (E) can optionally be stored under stirring. This can be achieved, for example, by a rod stirrer or an anchor stirrer.

[0127] Another subject of the present invention is a method for producing particles (P) consisting of a core (K) comprising a polymer material and a shell (H) consisting of particulate solids (F).

[0128] In the second step, a material (S) suitable for addition polymerization, condensation polymerization or chain polymerization and selected from siloxanes and silanes that is partically stable, is subjected to addition polymerization, chain polymerization or condensation polymerization.

[0129] The second step is preferably performed such that the amount of polymerizable material (S) in the particle-stabilized aqueous Pickerling emulsion (E) is less than 70% by weight, preferably less than 60% by weight, more preferably less than 50% by weight, and particularly preferably less than 40% by weight. Prior to the second step, the particle-stabilized Pickerling emulsion (E) is preferably diluted with water or a water-soluble organic solvent, more preferably with water.

[0130] In methods suitable for producing particles (P), polymerizable materials (S) undergo addition polymerization, chain polymerization, or condensation after mixing in the first step.

[0131] Siloxanes or silanes may require hydrolysis prior to condensation, for example, if they are alkoxy- or acetoxy-substituted silanes or siloxanes. In the case of sufficiently reactive silanes and siloxanes, the presence of water is sufficient to optionally induce hydrolysis and subsequent condensation. In the case of less reactive silanes and siloxanes, a catalyst is required to optionally induce the hydrolysis and condensation of the siloxanes and silanes. These catalysts can be acids or bases or can be metal catalysts, such as Group IV transition metal catalysts or tin catalysts commonly used to accelerate hydrolysis, condensation reactions, or transesterification reactions. Suitable acids or bases, in addition to known inorganic acids and metal salts, include acidic or basic silanes or siloxanes.

[0132] Preferred alkaline catalysts are NaOH, KOH, ammonia, and NEt3.

[0133] Preferred acidic catalysts include p-toluenesulfonic acid, aqueous or gaseous HCl, and sulfuric acid.

[0134] If the method involves chain polymerization, this could be, for example, a free radical polymerization of an olefinic unsaturated siloxane or a silane.

[0135] If the material (S) contains silanes or siloxanes suitable for addition polymerization, the material (S) is preferably mixed with a transition metal catalyst such as a platinum catalyst, especially when it contains siloxanes that can react with each other in a hydrosilylation reaction.

[0136] The process involves causing a finely granular solid (F) of a stable siloxane phase or silane phase during condensation, chain polymerization, or addition polymerization to react with, or at least to, the surface of the condensation or polymerization product forming the core (K), or to have a stable interaction with it, such as hydrogen bonding, van der Waals interactions, or other directional interactions, or to combine these directional interactions such that the solid (F) is anchored to the core (K) composed of the condensation or chain polymerization product of the material (S).

[0137] The surface of the particles (P) can optionally be modified by treatment with reactive silanes or siloxanes. These can be added directly, after the Pickering emulsion production is completed, during the reaction phase of the second step, or after the reaction phase of the second step, before or after the separation of the particles (P) from the liquid or solid phase. This treatment is performed such that the silane or siloxane is covalently chemically bonded to the particles. The corresponding methods and processes are known to those skilled in the art.

[0138] After the reaction phase in the second step is completed, the Pickering emulsion (E) may optionally be stored under stirring. This can be achieved, for example, by using a rod stirrer or an anchor stirrer.

[0139] In a preferred embodiment, the particles (P) are separated, preferably by sedimentation, filtration or centrifugation, more preferably by filtration or centrifugation, and most preferably by centrifugation.

[0140] After separation, the particles (P) are preferably washed with a washing solution selected from FD water, methanol, ethanol and mixtures thereof.

[0141] In a preferred embodiment, the particles (P) are separated from the aqueous phase (W) in powder form. This can be achieved, for example, by filtration, sedimentation, centrifugation, or by drying in an oven or dryer, by spray drying, or by removing volatile components by applying appropriate reduced pressure.

[0142] Spray drying allows for the production of particles (P) with very high fineness without further processing. Static-dried particles (P) tend to form loose agglomerates, which can be loosened by suitable grinding methods, such as ball mills or air jet mills.

[0143] The particles (P) are more specifically characterized in that they have an average particle size d of 0.5 to 9 μm, preferably 0.8 to 8.5 μm, more preferably 1.0 to 8.0 μm, very preferably 1.5 to 7 μm, and particularly preferably 2 to 6 μm. 50The average particle size was measured using a Camsizer X2 from Retsch Technology (measurement principle: dynamic image analysis according to ISO 13322-2, measurement range: 0.8μm-30mm, analysis type: dry measurement of powders and particles, dispersion pressure = 2 bar).

[0144] Particles (P) preferably have a narrow particle size distribution range, characterized by a distribution range (d) 90 -d 10 The micrometer size is less than 20 μm, preferably less than 17 μm, more preferably less than 15 μm, and particularly preferably less than 8 μm.

[0145] More specifically, the particulate solid (F) used is substantially bonded to the surface of the polymer particle (P). The distribution of the particulate solid (F) used can be obtained from a TEM micrograph of a polished sheet of the embedded particles of the present invention. The particulate solid (F) is immersed in the crosslinked polymer product, preferably greater than 10 nm, more preferably greater than 20 nm, and very preferably greater than 30 nm, and protrudes from the crosslinked polymer product, preferably greater than 10 nm, more preferably greater than 20 nm, and very preferably greater than 30 nm (measured from the outer boundary of the crosslinked polymer product in each case), thus being firmly bonded to the surface of the particle (P). This is a significant advantage compared to commercially available products in which silicone elastomer particles are post-treated with silica. In the case of such products, silica is not immersed in the silicone elastomer and therefore is not firmly bonded to the surface.

[0146] The particles (P) are substantially spherical. The sphericity SPHT3 is preferably at least 0.8, more preferably at least 0.82, as determined by using a Camsizer X2 from Retsch Technology according to ISO 9276-6.

[0147] Compared to non-inventive silica-coated particles produced using the same amount of particulate solid (F) according to the prior art, the particles (P) have a significantly smaller particle size. As a result, these particles can be used in applications where the relatively large silica-coated particles according to the prior art are unsuitable. The particles of the present invention are able to produce a significantly finer structure or surface coating compared to the relatively large silica-coated particles according to the prior art, either during processing or during application, for example, through significantly smaller openings, gaps, or nozzles.

[0148] The particles (P) of the present invention are amphiphilic, meaning they are both hydrophilic (i.e., water-loving) and lipophilic (i.e., fat-loving). This means that the particles (P) of the present invention are readily dispersed not only in polar solvents (e.g., water or alcohol) but also in nonpolar solvents (e.g., aliphatic hydrocarbons or polydimethylsiloxane oil) without the addition of other dispersing aids or additives, such as organic emulsifiers or other surfactants. This is a significant advantage of the particles (P) of the present invention compared to uncoated silicone elastomer particles, which are highly hydrophobic and cannot be dispersed in polar solvents such as water or alcohol without the use of unwanted aids such as organic emulsifiers. In the case of the particles (P) of the present invention, the particulate solid (F) is firmly bonded to the surface and thus retains its amphiphilicity when dispersed in solvents. This is a significant advantage compared to prior art silicone elastomer particles post-treated with silica after curing, because in the case of particles not according to the present invention, the absorbed silica is not permanently bonded. The disadvantage of these particles according to the prior art is that when the particles are dispersed in a solvent, the non-permanently bonded silica separates completely or partially, thus causing the particles to become highly hydrophobic and no longer dispersible in polar solvents such as water.

[0149] Another subject of the present invention is silicone resin particles (P1) with an average diameter d50 of up to 9 μm produced by the methods described above, which are produced by addition crosslinking, condensation crosslinking, or chain polymerization crosslinking. Condensation crosslinked silicone resin particles (P1) are particularly preferred.

[0150] In this case, materials (S) suitable for addition polymerization, condensation polymerization or chain polymerization crosslink to form thermosetting silicone resins.

[0151] Preferred examples of silicone resins suitable for silicone resin particles (P1) are the aforementioned silicone resins related to reinforcing fillers, which are condensation crosslinked, and more particularly pure T resins.

[0152] Particulate-stabilized aqueous Pickerling emulsions (E) can be used for all purposes for which aqueous dispersions have been used to date. Particulate-stabilized aqueous Pickerling emulsions (E) can be used in cosmetic and pharmaceutical applications, cleaning and washing compositions, or applications involving alteration of the interfacial properties of solid and liquid substrates (e.g., hydrophobic compositions, adhesion promoters, release agents, paper coatings, or foam control compositions), for the production of w / o / w or o / w / o multiple emulsions as, for example, controlled-release systems, or for the separation of reactive substances.

[0153] Pickering emulsions (E) crosslink and cure to form elastomers or resins after water is removed. Therefore, particle-stabilized aqueous Pickering emulsions (E) can be used, for example, as sealants and adhesives, paints, coatings, and as electrically insulating or conductively hydrophobic coatings that repel sticky substances, or as a matrix or additive in such systems. Molded articles can also be produced using crosslinked emulsions (E).

[0154] Pickering emulsions (E) and granules (P) are used more specifically in cosmetics.

[0155] The particles (P) exhibit highly advantageous behavior, particularly for cosmetic applications. They do not tend to agglomerate or clump, thus dispersing very easily and producing a velvety feel on the skin. This behavior was not observed in uncoated silicone elastomer particles not according to the invention. When such particles are dispersed on the skin, they tend to form spheres and produce an unpleasant sensation.

[0156] Compared to the non-inventive particles that are not coated with silica, particles (P) have a relatively large surface area. As a result, particles (P) are able to absorb a greater amount of skin fluid and produce a dry skin sensation for a relatively longer period of time.

[0157] Compared to non-inventive particles that are not coated with silica, silica-coated particles are able to absorb a greater amount of functional substances, such as fragrances, skincare products, vitamins, UV absorbers, or active pharmaceutical ingredients, on the silica surface. These substances may then be released onto the skin.

[0158] Compared to the non-inventive particles that are not coated with silica, the silica-coated particles exhibit amphiphilic behavior, which means that they are easily dispersed in both oily and aqueous liquids.

[0159] Compared to non-inventive particles that are not coated with silica, the surface of silica-coated particles can be more effectively wetted by liquids. Therefore, these particles can be dispersed into liquids (e.g., cosmetic formulations) much more easily and quickly, and they can also absorb liquids from their surfaces more quickly and easily—for example, they absorb sebum when applied to the skin as a cosmetic.

[0160] Compared to non-inventive silica-coated particles according to existing technology, the particles (P) have a significantly lower particle size. As a result, when applied to the skin in cosmetic applications, they provide a more comfortable and softer feel, and produce a more even skin appearance due to the finer coverage. Consequently, unevenness and imperfections on the skin are more effectively concealed.

[0161] The particles (P) have a larger surface area compared to non-inventive silica-coated particles according to the prior art, and are therefore able to absorb a greater amount of skin fluids or functional substances or active pharmaceutical ingredients. Example

[0162] Solid content:

[0163] 10g of the aqueous dispersion was mixed with an equal volume of ethanol in a porcelain dish and evaporated to constant weight at 150°C in a drying oven purged with N2. The solid content (%) is calculated as follows: s *100 / 10g, mass of dried residue m S The solid content is given.

[0164] Average particle size (d) 50 ):

[0165] The measurement of d was performed using a Camsizer X2 from Retsch Technology (measurement principle: dynamic image analysis based on ISO 13322-2; measurement range: 0.8μm-30mm; analysis type: dry measurement of powders and particles; dispersion pressure = 2 bar). 50 .

[0166] Methanol value:

[0167] The methanol value is determined by preparing defined mixtures of water and methanol. In separate experiments, these water-methanol mixtures are covered with a defined amount of dried particles and shaken under defined conditions (e.g., gently shaken by hand or through a drum mixer for about 1 minute). The methanol value is determined for water-methanol mixtures where the particles just barely sink, and for water-methanol mixtures with a higher alcohol content where the particles just sink. The methanol content in the latter part of the water gives the methanol value.

[0168] Example 1: Preparation of silica aqueous dispersion

[0169] In a dissolver running at 650 rpm, 1300 g of [a substance] was passed through to achieve a BET specific surface area of ​​200 m². 2 / g of hydrophilic starting silica (as named) Partially hydrophobic pyrolytic silica with 71% residual silanol content and 0.95% carbon content, obtained by reacting N20 (obtained from Wacker-Chemie GmbH, Munich) with dimethyldichlorosilane according to EP 1433749 A1, was batch-added to 5200 g of completely softened (FD) water under stirring. After complete addition of silica, dispersion was continued for another 60 minutes at 650 rpm. This produced a high-viscosity dispersion with 20% solids content and a pH of 4.2.

[0170] Example 2: General procedure for producing Pickering emulsions of silanes and / or siloxanes suitable for chain polymerization, polycondensation, or addition polymerization using Ultra-Turrax in a batch process.

[0171] Step 1: Weigh the silica dispersion described in Example 1 into a suitable 1000 mL stainless steel container and stir at 10000 rpm for 10 minutes using an Ultra-Turrax T50 mixer. The viscosity of the dispersion decreases. Optionally, add FD water and mix thoroughly. according to Example 7, 8 or 9 one The prepared mixed silicone oil component was added to a stirred silica dispersion and then homogenized for 10 minutes at 10,000 rpm using Ultra-Turrax under ice-cooling conditions. During this procedure, the temperature of the mixture should not rise above 35°C. The result is a high-viscosity white composition (emulsion (E)).

[0172] Step 2: Dilute the high-viscosity composition from Step 1 to a silicone oil content of 30% by adding three equal parts of FD water. After each part of FD water, stir at 6000 rpm for 3 minutes. This produces a highly fluid white O / W emulsion.

[0173] Example 3: General procedure for producing Pickering emulsions of silanes and / or siloxanes suitable for chain polymerization, condensation polymerization, or addition polymerization using a solvent

[0174] Step 1: Weigh the silica dispersion described in Example 1 into a suitable stirring vessel and stir at 6000 rpm for 10 minutes using a Labo-Top planetary dissolver from PC Laborsystem, CH. During this process, the viscosity of the dispersion decreases. Optionally, add FD water and mix thoroughly. This will be done according to Example 7, 8, or 9. one The prepared mixed silicone oil component was added to the stirred silica dispersion and homogenized in a dissolver at 6000 rpm for 10 minutes under water cooling. During this process, the temperature of the mixture should not rise above 35°C. The result is a white, high-viscosity composition.

[0175] Step 2: Dilute the high-viscosity composition from Step 1 to a silicone oil content of 30% by adding three equal parts of FD water at 1000 rpm. After each part of FD water, stir at 1000 rpm for 3 minutes. This produces a highly fluid white O / W emulsion.

[0176] Example 4: General procedure for producing Pickering emulsions of silanes and / or siloxanes suitable for chain polymerization, polycondensation, or addition polymerization using Ultra-Turrax in a metering addition method.

[0177] Compared to Example 2, the mixed oil components were slowly metered in over 15 minutes while being homogenized at 10,000 rpm using Ultra-Turrax.

[0178] Example 5: General procedure for producing silica-coated silicone particles from a Pickering emulsion of a silicone oil component suitable for polycondensation.

[0179] According to Example B2 or Example B3, a Pickering emulsion suitable for polycondensation was produced from a silicone oil component suitable for polycondensation produced according to Example B8 or B9. 250 g of this polycondensation-suitable Pickering emulsion was mixed with 1.5 g of p-toluenesulfonic acid. The reaction mixture was stirred at room temperature for 24 hours. The result was a white, highly fluid dispersion. Particulates were removed by filtration, and the mixture was dried in a drying oven at 80°C for 24 hours. This produced a fine white powder.

[0180] Example 6: General procedure for producing silica-coated silicone particles from Pickering emulsions of silanes and / or siloxanes suitable for addition polymerization

[0181] According to Example B2 or Example B3, a Pickering emulsion suitable for polymerization was produced from silicone oil component B7. 250 g of this polymerization-suitable Pickering emulsion was stirred at 80°C for 24 hours. The result was a white, highly fluid dispersion. Particles were removed by filtration, and the mixture was dried in a drying oven at 80°C for 24 hours. This produced a fine white powder.

[0182] Example 7: Production of silicone oil component B7 suitable for addition polymerization

[0183] Using a laboratory stirring apparatus, 375 g of vinyl dimethyl siloxy-terminated polydimethylsiloxane with a viscosity of 1000 mPas (25°C) and 264 g of vinyl dimethyl siloxy-terminated polydimethylsiloxane with a viscosity of 20000 mPas (25°C) were uniformly mixed. Then, 274 g of [Me3SiO] was added. 1 / 2 ] 26.65 [ViMe2SiO 1 / 2 ] 3.72 [SiO 4 / 2 ] 42.78 [HO 1 / 2 ] 1.02 [EtO 1 / 2 ] 5.93The vinyl-containing silicone resin (molecular weight determined by SEC (toluene eluent): Mw = 5300 g / mol; Mn = 2560 g / mol) was mixed and stirred until completely dissolved. Then, 0.45 g of a solution containing 1% Pt platinum-containing symmetric-divinyltetramethyldisiloxane complex and 5.6 g of 1,1,3,3-tetramethyl-1,3-divinyldisiloxane were added and mixed evenly with stirring.

[0184] The base composition obtained in this manner was uniformly mixed with 114 g of a copolymer composed of dimethylsiloxy, methylhydrosiloxy, and trimethylsiloxy units, which had a viscosity of 40 mPas at 25°C and a SiH content of 0.40%. According to Example 2 or Example 3, the resulting reaction mixture was not storable and emulsified within one hour of its formation.

[0185] Example 8: Production of silicone oil component B8 suitable for polycondensation

[0186] The silicone composition B8 suitable for polycondensation used is a methoxyl oligomerization product of methyltrimethoxysilane with a molecular weight of Mw = 1200 and a methoxyl content of about 30% by weight, which is produced according to conventional methods.

[0187] Example 9: Production of silicone oil component B8 suitable for polycondensation

[0188] The silicone composition B9 used, suitable for polycondensation, has the composition [MeSiO2]. 3 / 2 ] 23 [EtO 1 / 2 ] 27 The silicone resin, produced according to conventional methods, has molecular weights of Mw = 2560 g / mol and Mn = 900 g / mol as determined by SEC (toluene eluent), and viscosity (dynamic, 25°C) of 25 mPa·s.

[0189] Table 1a (According to an embodiment of the present invention)

[0190]

[0191] *Crosslinking type: a = addition crosslinking; c = condensation crosslinking

[0192] Table 1b (According to an embodiment of the present invention)

[0193]

[0194] *Crosslinking type: a = addition crosslinking; c = condensation crosslinking

[0195] Table 2 (Examples not based on the present invention)

[0196]

[0197] *Crosslinking type: a = addition crosslinking; c = condensation crosslinking. Comparative Example C6: Production of non-inventory particles according to WO07113095.

[0198] Silicon dioxide-coated silicone resin particles not according to the invention were prepared according to Examples 1a) to 1c) of WO07113095. In this case, Q1 = 7.7, Q2 = 79.5 and Q3 = 91.5. A solid with an average particle size d50 = 9.3 μm and a distribution range (d90–d10) = 27.2 was obtained.

[0199] Example of use

[0200] Example 21: Sensory evaluation in cosmetic applications

[0201] A trained group of subjects evaluated the sensory quality of the subdivided silica-coated silicone particles of the present invention from Examples 13 and 18, and the non-inventive silica-coated silicone particles from Comparative Examples C3 and C5. After application to the skin, the sensory quality of the residues was evaluated relative to each other. Table 3 shows the average ratings given by the subjects, where grade 0 corresponds to a preferred velvety smooth skin feel, and grade 5 corresponds to an undesirable prickly, rough skin feel.

[0202] Table 3 – Sensory Quality Evaluation:

[0203]

[0204] *Not based on this invention

[0205] Example 22: Use in coatings

[0206] A silicone coating was produced. This was accomplished by uniformly mixing 2 parts of the finely divided silica-coated silicone particles of the present invention from Example 18 with 98 parts of silicone composition B7 using a dissolver at 6000 rpm for 10 minutes, while maintaining the temperature at 20°C. The resulting composition was applied to a glass plate using a 10 μm spatula. This provided a smooth, transparent coating.

[0207] Comparative Example C7: Use in Coatings

[0208] Compared to Example 22, non-inventive silica-coated silicone particles from Comparative Example C5 were used. The resulting coating was uneven and had many white particles and streaks.

[0209] Example 23: Sensory evaluation during cosmetic use

[0210] 100 mg of the finely subdivided silica-coated silicone particles of the present invention from Example 13 were uniformly dispersed on a 4 cm diameter circular area on the unwashed lower arm of the subject. The result was a slightly whitish skin area that was dry, uniform, and visually homogeneous. This is an indication that the sebum present was completely absorbed by the skin surface.

[0211] Comparative Example C8: Sensory Evaluation in the Use of Cosmetics

[0212] Compared to Example 23, prior art silicone particles (Tospearl 2000B microbeads available from Momentive Performance Materials) were used. Upon dispersal, the particles clump together and produce an unattractive, uneven skin appearance. This is an indication that the sebum present cannot be fully absorbed by the skin surface.

Claims

1. A method for preparing a particulate-stabilized aqueous Pickerling emulsion (E) of a material (S) selected from siloxanes and silanes, suitable for addition polymerization or condensation polymerization: Mixed aqueous phase (W) The material (S), and Particulate silicon IV oxide solid (F), Forming an average diameter d 50 Droplets of up to 9 μm in size comprising the material (S) and the particulate silicon IV oxide solid (F), The condition is: in a particle-stable Pickering emulsion. The mass ratio Q1 = m(F) / m(S) * 100 is any value from 3 to 25. The mass ratio Q2 = m(S) / (m(S) + m(W)) * 100 is any value from 50 to 75, and The relationship between Q1 and Q2 is: Q2 = -(1.56*Q1) + Q3, where Q3 is a value between 77.0 and 89.

0. Where d 50 The measurements were taken using a Camsizer X2 from Retsch Technology. The measurement principle was based on dynamic image analysis according to ISO 13322-2. The measurement range was 0.8 μm to 30 mm. The analysis type was dry measurement of powders and particles. The dispersion pressure was 2 bar.

2. A method for preparing a partically stable aqueous Pickerling emulsion (E) of a material (S) suitable for chain polymerization and selected from siloxanes and silanes: Mixed aqueous phase (W) The material (S), and Particulate silicon IV oxide solid (F), Forming an average diameter d 50 Droplets of up to 9 μm in size comprising the material (S) and the particulate silicon IV oxide solid (F), The condition is: in a particle-stable Pickering emulsion. The mass ratio Q1 = m(F) / m(S) * 100 is any value from 3 to 25. The mass ratio Q2 = m(S) / (m(S) + m(W)) * 100 is any value from 50 to 75, and The relationship between Q1 and Q2 is: Q2 = -(1.56*Q1) + Q3, where Q3 is a value between 77.0 and 89.

0. Where d 50 The measurements were taken using a Camsizer X2 from Retsch Technology. The measurement principle was based on dynamic image analysis according to ISO 13322-2. The measurement range was 0.8 μm to 30 mm. The analysis type was dry measurement of powders and particles. The dispersion pressure was 2 bar.

3. The method of claim 1 or 2, wherein the material (S) is at least one siloxane having general formula (IV), or at least one silane having general formula (V), or a formulation of two or more such siloxanes of general formula (IV) and / or silanes of general formula (V): [A 1 MR 9 pSiO(4-pm) / 2](IV), in A 1 It is a hydrogen group or a hydrocarbon group containing no more than 30 carbon atoms and optionally additionally containing heteroatoms selected from O, S, Si, Cl, F, Br, P or N atoms. R 9 This indicates an alkoxy or aryloxy group, or a hydroxyl group or H, having no more than 18 carbon atoms. m and p represent the values ​​0, 1, 2, or 3, respectively, and the sum of m and p is greater than 0 and less than 4. (R 10 ) 4-o -Si-(OR 11 ) o (V), Where o is a value of 1, 2, 3 or 4, R 10 The term represents a straight-chain or branched alkyl group having 1 to 16 carbon atoms, wherein non-adjacent carbon atoms are optionally substituted with oxygen atoms, or represents an aryl group, or an organic functional group selected from the following: phosphonic acid monoester group; phosphonic acid diester group; phosphonic acid group; methacryloyloxy; acryloyloxy; vinyl; mercapto; isocyanate group; hydroxyl; hydroxyalkyl; epoxy; glycidoxy; morpholino; piperazine; a primary, secondary, or tertiary amino group having one or more nitrogen atoms, wherein the nitrogen atoms are optionally substituted with hydrogen or a monovalent aromatic, aliphatic, or cycloaliphatic hydrocarbon group; a carboxylic acid group; a carboxylic anhydride group; an aldehyde group; a carbamate group; a urea group; wherein the group R 10 Optionally bonded directly to silicon atoms or optionally separated from them by a carbon chain of 1-6 carbon atoms, and R 11 It is a monovalent, straight-chain or branched aliphatic or alicyclic hydrocarbon group, wherein non-adjacent carbon atoms are optionally substituted with heteroatoms O, N, P, S, Cl, F, Br or Si, wherein the free valence of the relevant heteroatoms is optionally satisfied by straight-chain or branched alkyl or hydrogen atoms, or a monovalent aromatic group or a group of the formula -C(=O)-R. 12 The group, wherein R 12 It is a monovalent straight-chain or branched aliphatic or cycloaliphatic hydrocarbon group or a monovalent aromatic hydrocarbon group, wherein the selected silane is optionally present in a non-hydrolyzed form, a hydrolyzed form, or a hydrolyzed and partially condensed form, or a hydrolyzed and condensed form, or a mixture of these forms.

4. The method of claim 1 or 2, wherein the average particle size of the particulate silicon IV oxide solid (F) is less than 1000 nm.

5. The method of claim 1 or 2, wherein the carbon content of the particulate silicon IV oxide solid (F), as measured by elemental analysis of the dried particulate solid, is 0.1-4% by weight.

6. A particle-stabilized aqueous Pickering emulsion (E) that can be produced by the method of any one of the preceding claims.

7. A method for producing particles (P), said particles (P) comprising a core (K) containing a polymer material and a shell (H) composed of particulate silicon IV oxide solid (F), in, In the first step, a particle-stabilized aqueous Pickering emulsion (E) of said material (S) is produced by the method according to any one of claims 1 to 4, and In the second step, the material (S) of the aqueous Pickerling emulsion (E) that stabilizes the particles is subjected to addition polymerization or condensation.

8. A method for producing particles (P), said particles (P) comprising a core (K) containing a polymer material and a shell (H) composed of particulate silicon IV oxide solid (F), in, In the first step, a particle-stabilized aqueous Pickering emulsion (E) of said material (S) is produced by the method according to any one of claims 1 to 4, and In the second step, the material (S) of the aqueous Pickerling emulsion (E) that stabilizes the particles undergoes chain polymerization.

9. The method of claim 7 or 8, wherein the particles (P) have a distribution range d of less than 20 μm. 90 -d 10 .

10. Addition-crosslinked or condensation-crosslinked silicone resin particles (P1) having an average diameter d50 of up to 9 μm, produced by the method described in any one of claims 7-9.

11. Chain-polymerized crosslinked silicone resin particles (P1) having an average diameter d50 of up to 9 μm, produced by the method described in any one of claims 7-9.

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