JP3627796B2 - Method for producing polymer-coated powder - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a polymer-coated powder having almost no aggregation, particularly a silicon-based polymer-coated powder, and in particular, a raw material for metal-coated powder useful as a filler, antibacterial agent, etc. having conductivity and catalytic activity. The present invention relates to a method for producing a polymer-coated powder suitable as the above.
[0002]
[Prior art and problems to be solved by the invention]
Metal-coated powders produced by coating powders, especially non-conductive powders with various metals, have a high degree of freedom in selecting materials to be used as base fillers. Since various applications such as a coating agent and a coating agent can be expected, various manufacturing methods have been studied, and in particular, a method using an electroless plating method has been put into practical use.
[0003]
However, the electroless plating method has a problem in the adhesion between the plating metal and the powder, and a silane coupling agent (for example, γ-aminopropyl) is used to produce a powder having a metal film with better adhesion. A method using a silane monomer such as triethoxysilane (Japanese Patent Laid-Open Nos. 61-257479 and 62-297471) and a method using a palladium colloid sol using a reducing agent such as NaBH ₄ ( Japanese Patent Laid-Open No. 63-79975), a method of etching the powder surface, and the like have been proposed. However, these methods have not always obtained good metal-coated powders.
[0004]
The present invention has been made in view of the above circumstances, and is coated with a polymer compound coating, particularly a silicon-based polymer compound coating with good adhesion, and has almost no aggregation between powders, and has a conductivity and catalytic activity. It is an object of the present invention to provide a method for producing a polymer-coated powder, which can obtain a polymer-coated powder suitable as a raw material for a metal-coated powder useful as an antibacterial agent, etc. by a simple and inexpensive process.
[0005]
Means for Solving the Problem and Embodiment of the Invention
As a result of intensive studies to achieve the above object, the present inventor treated a powder with a silicon-based polymer compound having a Si—Si bond or a Si—H bond in a molecule dissolved in an organic solvent, After performing the step of coating the powder surface with the coating film made of the silicon-based polymer compound, the organic solvent is dispersed in the organic solvent in which the powder coated with the coating film made of the silicon-based polymer compound is dispersed in the first step. After adding and mixing other solvents that cause phase separation with the solvent, these solvents are distilled off at the same time and dried to obtain a silicon polymer coated powder coated with a non-aggregated silicon polymer compound. In other words, the powder surface is firmly coated with a coating made of a silicon-based polymer compound with good adhesion in such an inexpensive and simple process. The phases with each other By removing the solvent from the dispersion in a mixed solvent containing two or more types of solvents that cause separation and drying, a non-agglomerated silicon-based polymer-coated powder that prevents contact between particles is obtained. It has been found that this silicon-based polymer-coated powder can be widely used as a raw material for metal-coated powders used for fillers, antibacterial agents and the like having conductivity and catalytic activity.
[0006]
In this case, the silicon-based polymer compound is a very interesting polymer because of its metallic properties, electron delocalization, high heat resistance and flexibility, and good thin film formation characteristics compared to carbon. A polysiloxane having a hydrogen atom directly bonded to a silicon atom is known as a polymer compound having reducibility and is used in various applications. Furthermore, it is well known that polysilane is used as a precursor of silicon carbide ceramic material, and polysiloxane is used as a precursor of silicon oxide ceramic material.
[0007]
When the present applicant contacts a powder whose surface is treated with a silicon-based polymer compound having such a reducing action with a solution containing metal ions, a metal colloid is generated and retained on the powder surface. And a method for producing a metal film powder having good adhesion utilizing this was proposed in Japanese Patent Application No. 10-121836. This method is characterized in that a powder surface-treated with a silicon-based polymer compound is agglomerated during production. There was a risk.
[0008]
Therefore, the present inventor has further researched on the production technology of the powder surface-treated with the silicon-based polymer compound, and at the time of producing the silicon-based polymer-coated powder, two or more kinds of solvents that cause phase separation from each other are used. Dispersing in a mixed solvent containing the solution, and distilling and drying the liquid effectively prevents contact between particles, and makes it possible to easily and inexpensively efficiently produce a good silicon-based polymer-coated powder with little aggregation. It has been found that this method can be produced and that such a method is effective for other polymer-coated powders, and has led to the present invention.
[0009]
Therefore, in the present invention, after the powder coated with the polymer compound coating is mixed and dispersed in two or more kinds of mixed liquids causing phase separation, the liquid is distilled off at the same time, Provided is a method for producing a polymer-coated powder characterized by drying. In addition, the present invention provides a method for obtaining a non-aggregated silicon-based polymer-coated powder. (1) A silicon-based high polymer having a Si—Si bond or a Si—H bond in a molecule obtained by dissolving the powder in an organic solvent. A step of treating with a molecular compound and coating the surface of the powder with a film comprising the silicon-based polymer compound; (2) an organic in which the powder coated with the film comprising the silicon-based polymer compound in the first step is dispersed; A silicon-based polymer-coated powder comprising a step of adding to and mixing with another solvent that causes phase separation with the organic solvent, and then simultaneously distilling off both the solvents and drying the powder. A method for manufacturing a body is provided.
[0010]
Hereinafter, the present invention will be described in more detail. In the method for producing a polymer-coated powder according to the present invention, a powder coated with a polymer compound coating is mixed in two or more kinds of mixed liquids that cause phase separation. After the dispersion, the liquid is simultaneously distilled off and the powder is dried, whereby a non-aggregated polymer-coated powder is obtained.
[0011]
In this case, the polymer compound is appropriately selected, but the present invention is preferably used particularly when obtaining a non-aggregated silicon-based polymer-coated powder.
[0012]
When obtaining such a non-aggregated silicon-based polymer-coated powder,
(1) The powder is treated with a silicon-based polymer compound having a Si-Si bond or Si-H bond in a molecule dissolved in an organic solvent, and the powder surface is coated with a film made of the silicon-based polymer compound. Process,
(2) After adding and mixing the organic solvent in which the powder coated with the film made of the silicon-based polymer compound in the first step is dispersed and mixing the organic solvent with the solvent, the two solvents are simultaneously mixed. It can be carried out by a step of distilling off and drying the powder.
[0013]
First, in the first step, the powder is treated with a silicon polymer compound having a Si—Si bond or Si—H bond in a molecule dissolved in an organic solvent, and the powder surface is coated with a silicon polymer. It is to be coated.
[0014]
Examples of the powder used in the present invention include insulating powders such as silica, alumina, and alumina silicate, semiconductive powders such as titanium oxide and zinc oxide, and conductive powders such as carbon and aluminum. Can be mentioned. The shape is not particularly limited, and various shapes such as powder, fiber, and flake can be used.
[0015]
In the present invention, a silicon-based polymer compound having a Si—Si bond or Si—H bond in the molecule is used as the silicon-based polymer compound having a reducing action.
[0016]
Here, as the silicon-based polymer compound having a Si—Si bond in the molecule, polysilane is preferably used, and polysilane represented by the following general formula (1) is preferable.
[0017]
(R ¹ _m R ² _n X _p Si) _q (1)
In the above formula (1), R ¹ and R ² are each a hydrogen atom, a substituted or unsubstituted monovalent hydrocarbon group, and R ¹ and R ² may be the same or different from each other, As the monovalent hydrocarbon group, an aliphatic, alicyclic or aromatic monovalent hydrocarbon group is used. As the aliphatic or alicyclic monovalent hydrocarbon group, those having 1 to 12 carbon atoms, particularly 1 to 6 carbon atoms are preferable. For example, alkyl groups such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. And cycloalkyl groups such as a group, a cyclopentyl group, and a cyclohexyl group. As the aromatic monovalent hydrocarbon group, those having 6 to 14 carbon atoms, particularly 6 to 10 carbon atoms are suitable, and examples thereof include a phenyl group, a tolyl group, a xylyl group, a naphthyl group, and a benzyl group. In addition, as the substituted monovalent hydrocarbon group, one or all of the hydrogen atoms of the unsubstituted monovalent hydrocarbon group exemplified above are substituted with a halogen atom, an alkoxy group, an amino group, an aminoalkyl group, etc. For example, a monofluoromethyl group, a trifluoromethyl group, an m-dimethylaminophenyl group and the like can be mentioned.
[0018]
X is the same group as R ¹ , an alkoxy group, a halogen atom, an oxygen atom or a nitrogen atom, and the alkoxy group preferably has 1 to 4 carbon atoms such as a methoxy group, an ethoxy group or an isopropoxy group. Examples of the halogen atom include a fluorine atom, a chlorine atom and a bromine atom. Of these, a methoxy group and an ethoxy group are preferably used as X.
[0019]
m is 0.1 ≦ m ≦ 1, preferably 0.5 ≦ m ≦ 1, n is 0.1 ≦ n ≦ 1, preferably 0.5 ≦ n ≦ 1, p is 0 ≦ p ≦ 0.5, Preferably 0 ≦ p ≦ 0.2, and 1 ≦ m + n + p ≦ 2.5, preferably 1.5 ≦ m + n + p ≦ 2, and q is 2 ≦ q ≦ 100,000, preferably 10 It is an integer in the range of ≦ q ≦ 10,000.
[0020]
In addition, a silicon-based polymer compound having a hydrogen atom (Si—H group) directly bonded to a silicon atom has the following general formula (2) having a Si—H group in the side chain and a Si—O—Si bond in the main chain. Is preferably used.
[0021]
(R ³ _a R ⁴ _b H _c SiO _d ) _e (2)
In the above formula, R ³ and R ⁴ are each a hydrogen atom, a substituted or unsubstituted monovalent hydrocarbon group, an alkoxy group or a halogen atom, and R ³ and R ⁴ may be the same or different from each other. As the monovalent hydrocarbon group, an aliphatic, alicyclic or aromatic monovalent hydrocarbon group is used. As the aliphatic or alicyclic monovalent hydrocarbon group, those having 1 to 12 carbon atoms, particularly 1 to 6 carbon atoms are preferable. For example, alkyl groups such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. And cycloalkyl groups such as a group, a cyclopentyl group, and a cyclohexyl group. As the aromatic monovalent hydrocarbon group, those having 6 to 14 carbon atoms, particularly 6 to 10 carbon atoms are suitable, and examples thereof include a phenyl group, a tolyl group, a xylyl group, a naphthyl group, and a benzyl group. The substituted aliphatic, alicyclic or aromatic monovalent hydrocarbon group includes a part or all of the hydrogen atoms of the unsubstituted monovalent hydrocarbon group exemplified above as a halogen atom, alkoxy group, amino group. And a group substituted with an aminoalkyl group, such as a monofluoromethyl group, a trifluoromethyl group, and an m-dimethylaminophenyl group. As the alkoxy group, those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, and an isopropoxy group are preferable. Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom. A group and an ethoxy group are preferably used.
[0022]
a is 0.1 ≦ a ≦ 1, preferably 0.5 ≦ a ≦ 1, b is 0.1 ≦ b ≦ 1, preferably 0.5 ≦ b ≦ 1, c is 0.01 ≦ c ≦ 1, The number is preferably 0.1 ≦ c ≦ 1 and 1 ≦ a + b + c ≦ 2.5, preferably 1 ≦ a + b + c ≦ 2.2. d is 1 ≦ d ≦ 2. e is an integer in the range of 2 ≦ e ≦ 100,000, preferably 10 ≦ e ≦ 10,000.
[0023]
Here, as a method for treating silicon-based polymer with powder, a wet method using a liquid such as a solvent is adopted, and the polymer is dissolved in a solvent and mixed with the powder in a diluted state, and this slurry is stirred in a container. A stirring method in which blades are rotated and dispersedly contacted, and a spraying method in which the slurry is dispersed in an air stream and dried instantaneously are preferably used.
[0024]
As the first solvent for dissolving the silicon-based polymer compound, an organic solvent, particularly a hydrocarbon compound having 6 to 12 carbon atoms, is preferable, for example, an aromatic hydrocarbon such as benzene, toluene, xylene, hexane, octane, An aliphatic hydrocarbon solvent such as cyclohexane is preferably used. The concentration of the polymer solution is preferably 0.01 to 50% (% by weight, hereinafter the same), particularly 1 to 20%.
[0025]
Next, in the second step, the organic solvent in which the powder coated with the coating composed of the silicon-based polymer compound in the first step is dispersed and mixed with another solvent that causes phase separation with this solvent. These solvents are simultaneously distilled off and dried to obtain a non-aggregated silicon polymer coated powder.
[0026]
In this case, in the second step, after the powder is coated with the silicon polymer compound in the organic solvent in which the silicon polymer compound is dissolved in the first step, the organic solvent is not completely distilled off. In the state where the silicon-based polymer-coated powder is dispersed in the organic solvent, it is preferable to add and mix this solvent with another solvent capable of causing phase separation. By performing this step, the powder whose surface is covered with the silicon-based polymer dispersed in the organic solvent is separated by the liquid causing phase separation with the solvent, and the contact between the particles is prevented. Since it is dried, powder aggregation can be prevented.
[0027]
As said organic solvent, what was mentioned at the 1st process can be used, As other solvents which can raise | generate phase separation with this organic solvent, ketones, such as water, acetone, and methyl ethyl ketone, Esters, such as ethyl acetate In addition, one kind of polar solvent such as alcohols such as methanol and ethanol can be used alone, or two or more kinds thereof can be used in combination. Among them, water or alcohols such as methanol and ethanol are preferably used. it can.
[0028]
The amount of addition of these other solvents is preferably 10 to 1,000 parts by weight, particularly 50 to 200 parts by weight, based on 100 parts by weight of the organic solvent. Since no phase separation occurs, the effect of preventing aggregation may not be obtained.
[0029]
In addition, after addition of these other solvents, it is preferable to sufficiently stir and mix.
[0030]
Thereafter, the solvent that is the dispersion medium is simultaneously distilled off by raising the temperature or reducing the pressure, etc., but usually at a temperature equal to or higher than the boiling point of the dispersion medium under reduced pressure, specifically, a reduced pressure of 1 to 100 mmHg. It is effective to dry with stirring at about 40 to 200 ° C. below.
[0031]
After the treatment, the solution is left to stand at a temperature of about 40 to 200 ° C. in a dry atmosphere or under reduced pressure for a while, so that the solvent is completely distilled off and the treated powder is dried. Can be manufactured.
[0032]
In the present invention, the silicon-based polymer-coated powder can be subjected to a metal salt treatment as necessary. In this process, the surface of the silicon-based polymer-treated powder is brought into contact with a solution containing a metal salt. In this treatment, a metal colloid is formed on the surface of the coating film of the silicon-based polymer compound by the reducing action of the silicon-based polymer compound. And a metal film is formed.
[0033]
Here, as the metal salt, a metal salt having a standard oxidation-reduction potential of 0.54 V or more is suitable. More specifically, a salt such as gold (standard oxidation-reduction potential 1.50 V), palladium (standard oxidation-reduction potential 0.99 V), silver (standard oxidation-reduction potential 0.80 V), or the like is preferably used. It should be noted that a salt such as copper (standard oxidation-reduction potential 0.34 V) or nickel (standard oxidation-reduction potential 0.25 V) having a standard oxidation-reduction potential lower than 0.54 V is difficult to reduce with a silicon-based polymer compound.
[0034]
Examples of the gold salt include Au ⁺ or Au ³⁺ , and specific examples include NaAuCl ₄ , NaAu (CN) ₂ , NaAu (CN) _{4, and the} like. The palladium salt contains Pd ^{2+ and} can usually be expressed in the form of Pd—Z ₂ . Z is a salt of halogen such as Cl, Br, and I, acetate, trifluoroacetate, acetylacetonate, carbonate, perchlorate, nitrate, sulfate, oxide, and the like. Specific examples include PdCl ₂ , PdBr ₂ , PdI ₂ , Pd (OCOCH ₃ ) ₂ , Pd (OCOCF ₃ ) ₂ , PdSO ₄ , Pd (NO ₃ ) ₂ , PdO, and the like. The silver salt can be dissolved in a solvent to produce Ag ⁺ and can be usually expressed in the form of Ag-Z (Z can be a salt of perchlorate, borate, phosphate, sulfonate, etc.). . _{Specifically, AgBF 4, AgClO 4, AgPF} 6, AgBPh 4, Ag (CF 3 SO 3), AgNO 3 , and the like.
[0035]
As a contact method for treating powder with a solution containing a metal salt, a solution containing a metal salt is prepared using a solvent that does not dissolve the silicon-based polymer and can dissolve or disperse the metal salt. A method in which a powder coated with a silicon-based polymer film is put into and contacted with a metal salt is suitable. By performing the treatment in this manner, the metal salt is adsorbed and reduced on the surface of the silicon-based polymer film of the powder coated with the silicon-based polymer to form a metal-coated powder.
[0036]
Here, the solvent that does not dissolve the silicon-based polymer and can dissolve or disperse the metal salt includes water, ketones such as acetone and methyl ethyl ketone, alcohols such as methanol and ethanol, dimethylformamide, and dimethyl sulfoxide. And aprotic polar solvents such as hexamethylphosphoric triamide, among which water is preferably used.
[0037]
The concentration of the metal salt varies depending on the solvent in which the salt is dissolved, but is preferably from 0.01% to a saturated salt solution. If the concentration is less than 0.01%, the effect of the plating catalyst may not be sufficient. If the concentration exceeds the saturated solution, solid salt may be precipitated, which is not preferable. When the solvent is water, the concentration of the metal salt is preferably 0.01 to 20%, particularly preferably 0.1 to 5%. The silicon-based polymer-treated powder may be immersed in the metal salt solution at room temperature to 70 ° C. for 0.1 to 120 minutes, more preferably for about 1 to 15 minutes. Thereby, a metal can be formed on the film surface by the reducing action of the silicon-based polymer compound, and a metal colloid-treated powder can be produced.
[0038]
After the treatment, treatment with a solvent similar to the above not containing a metal salt, except for unnecessary metal salt not supported on the powder, it is preferable to dry and remove the unnecessary solvent from the powder at the end, Thereby, metal-coated powder can be obtained. Drying is usually preferably performed at 0 to 150 ° C. under normal pressure or reduced pressure.
[0039]
Furthermore, in the method of the present invention, if necessary, the metal-coated powder can be subjected to electroless plating after performing the above steps. By performing the electroless plating process using the metal colloid generated in the above process as a catalyst, it is possible to obtain a powder that is more completely coated with various metals.
[0040]
In this case, as the electroless plating solution, those containing metals such as copper, nickel, cobalt, palladium, gold, platinum, rhodium, etc. are preferably used, but those containing gold, copper, nickel are particularly preferred. The electroless plating solution generally contains a reducing agent such as sodium hypophosphite, hydrazine, or sodium borohydride in the metal salt, and a complexing agent such as sodium acetate, phenylenediamine, or sodium potassium tartrate. Usually, those containing metals such as copper, nickel, silver, and gold are commercially available as electroless plating solutions and can be obtained at low cost.
[0041]
The plating temperature is preferably 15 to 120 ° C., particularly 25 to 85 ° C., and the contact time is 1 minute to 16 hours, particularly 10 to 60 minutes. In addition, after the electroless plating treatment, it is desirable to finally wash with water in order to remove unnecessary surfactant.
[0042]
If necessary, an insulating layer made of a ceramic layer can be formed by subjecting the metal-coated powder to a high temperature treatment. The high temperature treatment is usually performed at 200 to 1200 ° C., particularly 300 to 900 ° C. for 1 minute to 24 hours, particularly 30 minutes to 4 hours. By this high-temperature treatment, the silicon-based polymer between the powder and the metal changes to ceramic, and has higher heat resistance, insulation, and adhesion. In particular, when polysilane is treated at high temperature, the Si-Si bond is broken and various elements enter and stabilize, so if the atmosphere at this time is performed in an oxidizing system such as in the air, such as ceramics of silicon oxide, ammonia gas, etc. When performed in a reducing atmosphere, a silicon nitride ceramic can be obtained, and when performed in an inert atmosphere such as argon or in a vacuum system, a silicon carbide ceramic can be obtained.
[0043]
【The invention's effect】
According to the method for producing a polymer-coated powder of the present invention, a metal-coated powder that is coated with a polymer compound that hardly aggregates particles and that is particularly useful as a filler or antibacterial agent having electrical conductivity and catalytic activity. A powder suitable as a raw material can be industrially advantageously produced. In particular, a metal-coated powder produced using a silicon-based polymer-coated powder as a raw material by the method of the present invention can be used to form a film having excellent heat resistance such as silicon oxide and silicon carbide by changing post-treatment conditions such as heat treatment. It can be formed into metal-coated powder and has wide application.
[0044]
【Example】
EXAMPLES Hereinafter, although a synthesis example, an Example, and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example.
[0045]
(Synthesis example)
Production of phenyl polysilane (hereinafter abbreviated as PPHS):
Bis (cyclopentadienyl) dimethylzirconocene as a catalyst in the system was prepared by adding a diethyl ether solution of methyllithium to bis (cyclopentadienyl) dichlorozirconocene in an argon-substituted flask. Phenylsilane was added to this at 50 times mole of the catalyst, and the mixture was heated and stirred at 150 ° C. for 24 hours. Thereafter, molecular sieves were added and filtered to remove the catalyst, whereby a PPHS solid having a weight average molecular weight of 2,600 was obtained almost quantitatively.
[0046]
〔Example〕
As the powder, spherical silica US-10 (manufactured by Mitsubishi Rayon Co., Ltd .; average particle size 10 μm) was used. 5 g of PPHS was dissolved in 65 g of toluene, and this solution was added to 100 g of US-10 and stirred for 1 hour to make a slurry. In a rotary evaporator, 30 g of toluene was distilled off at a temperature of 80 ° C. and a pressure of 45 mmHg to obtain PPHS-treated spherical silica. In this state, the PPHS-treated spherical silica was uniformly dispersed in toluene and was fluid.
[0047]
Next, when 35 g of water was added thereto and stirred vigorously, the water was mixed with the PPHS-treated spherical silica-containing toluene phase and the fluidity was lost. In this state, 35 g of toluene and 30 g of water were simultaneously distilled off again using a rotary evaporator at a temperature of 80 ° C. and a pressure of 45 mmHg. In this state, the PPHS-treated spherical silica was dispersed while being swollen into the foam, and was easily crushed by a roller or the like. When the powder was observed with a microscope, almost no aggregation was observed, and the shape was spherical.
[0048]
[Comparative example]
The same operation as in the example was performed except that no water was added to the PPHS-treated spherical silica uniformly dispersed in toluene. When 65 g of toluene was distilled off, the PPHS-treated spherical silica was in a solid state. The powder could not be crushed with a roller or the like, and a small amount was crushed and the powder was observed with a microscope.

Claims (5)

The powder coated with a polymer compound coating is mixed and dispersed in two or more mixed liquids that cause phase separation from each other, and then the liquid is distilled off simultaneously to dry the powder. A method for producing a polymer-coated powder. (1) The powder is treated with a silicon-based polymer compound having a Si-Si bond or Si-H bond in a molecule dissolved in an organic solvent, and the powder surface is coated with a film made of the silicon-based polymer compound. Process,
(2) After adding and mixing the organic solvent in which the powder coated with the film made of the silicon-based polymer compound in the first step is dispersed and adding another solvent that causes phase separation with the organic solvent, A method for producing a silicon-based polymer-coated powder comprising the step of simultaneously distilling off and drying the powder. The method for producing a silicon-based polymer-coated powder according to claim 2, wherein the silicon-based polymer compound having a Si-Si bond in the molecule is represented by the following general formula (1).
(R ¹ _m R ² _n X _p Si) _q (1)
Wherein R ¹ and R ² are each a hydrogen atom, a substituted or unsubstituted monovalent hydrocarbon group, X is the same group as R ¹ , an alkoxy group, a halogen atom, an oxygen atom or a nitrogen atom. 0.1 ≦ m ≦ 1, n is 0.1 ≦ n ≦ 1, p is 0 ≦ p ≦ 0.5, and 1 ≦ m + n + p ≦ 2.5, q is 2 ≦ q ≦ 100 , An integer of 1,000.) The method for producing a silicon-based polymer-coated powder according to claim 2, wherein the silicon-based polymer compound having a Si-H bond in the molecule is represented by the following general formula (2).
(R ³ _a R ⁴ _b H _c SiO _d ) _e (2)
(In the formula, R ³ and R ⁴ are each a hydrogen atom, a substituted or unsubstituted monovalent hydrocarbon group, an alkoxy group or a halogen atom. A is 0.1 ≦ a ≦ 1, b is 0.1 ≦ b. ≦ 1, c is 0.01 ≦ c ≦ 1, and 1 ≦ a + b + c ≦ 2.5, d is a number satisfying 1 ≦ d ≦ 2, e is an integer of 2 ≦ e ≦ 100,000 is there.) The method for producing a silicon-based polymer-coated powder according to claim 2, 3 or 4, wherein one organic solvent phase-separated from each other is a hydrocarbon compound having 6 to 12 carbon atoms, and the other solvent is a polar solvent.