A method for catalytic hydrosilylation reaction by ball milling and catalyst used

Abstract

The present application belongs to the field of chemical industry, in particular, the field of organic silicon synthesis, and specifically relates to a ball milling catalytic hydrosilylation reaction of various silanes or siloxanes containing Si-H bond and unsaturated hydrocarbon. The present application provides a preparation method of Rh-Ni-Cu cladding layer grinding ball, comprising the following steps: polishing, cleaning and drying the grinding ball; mixing Rh, Ni and Cu and drying; bonding the dried alloy powder on the surface of the treated grinding ball with a binder, placing the grinding ball on a cladding workbench, and performing laser cladding on the surface of the grinding ball to obtain a Rh-Ni-Cu cladding layer grinding ball. The present application also simultaneously provides a hydrogen addition method using the Rh-Ni-Cu cladding layer grinding ball as a catalyst. The method of the present application can promote the green and efficient production of the hydrosilylation reaction in the field of chemical industry.

Description

Technical Field

[0001] This invention belongs to the field of chemical engineering, particularly the field of organosilicon synthesis, and specifically relates to a ball milling catalysis method for hydrosilylation reactions of various silanes or siloxanes containing silane-hydrogen bonds with unsaturated hydrocarbons. Background Technology

[0002] Hydrosilylation is an addition reaction between silane compounds containing silane and unsaturated compounds under certain conditions. It is the most typical reaction for forming Si-C bonds. It is simple to operate, has mild conditions, few side reactions, and pure products, which is extremely beneficial to modern industrial production.

[0003] Early catalysts used in hydrosilylation were mainly noble metals such as Rh, Pt, Ir, and Ru. For example, Karstedt catalyst and Speier catalyst are both Pt-containing catalysts (Angewandte Chemie International Edition, 2020, 60(2):550-565). These noble metal catalysts often have high catalytic activity, but they have disadvantages such as high price, difficult operation and complex ligands.

[0004] For example, in the application of the hydrosilylation reaction of olefins with hydrosilanes disclosed in patent CN 113399001A, a platinum-based catalyst is used under nitrogen protection. The temperature is slowly increased, and triethylhydrosilane (1 mol) is added dropwise through a dropping funnel. The reaction temperature is maintained, and the reaction is stirred for several hours. After cooling to room temperature, the corresponding components are collected by vacuum distillation. Finally, the conversion rate of hexene is determined by GC-MS. The drawback of this method is that the catalyst preparation process is cumbersome, and the preparation process is difficult to industrialize.

[0005] The search for non-precious metal compounds (such as nickel, iron, cobalt, titanium, etc.) to replace precious metal catalysts has always been a key focus in the field of catalytic chemistry research.

[0006] Taking the hydrosilylation reaction of olefins as an example, Ni can be used as a catalyst to catalyze the hydrosilylation reaction of terminal olefins with hydrogen-containing siloxanes very efficiently, and the products are mainly anti-Markovnikov addition products. In this catalytic reaction, through... 1 Ni-silane intermediates were detected by H NMR and 29Si NMR, indicating that the active site in this reaction is the Ni-Si intermediate formed by the combination of Ni and silane, rather than the Ni-H intermediate.

[0007] Mechanochemistry is an emerging discipline that studies the chemical reactions, physicochemical properties, or internal microstructural changes of materials under the influence of mechanical forces. While most chemical synthesis processes occur in solution, mechanochemistry, relying on mechanical forces, requires virtually no solvents. It boasts low energy consumption, rapid reaction rates, and the ability to quantitatively synthesize a range of functional molecules. For example, patent CN 117209527A discloses a method for preparing a metal catalyst clad on the surface of a grinding ball using laser cladding technology, and employs mechanochemistry to synthesize organosilanes. However, there are currently no reports on using ball milling to catalyze hydrosilylation reactions. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to provide a method for catalyzing hydrosilylation reactions by ball milling and the catalyst used therein. The method uses Rh-Ni-Cu metal clad milling balls as catalysts and uses ball milling to catalyze the hydrosilylation reactions of various silanes or siloxanes containing silane-hydrogen bonds with unsaturated hydrocarbons.

[0009] That is, the present invention provides, on the one hand, a method for preparing Rh-Ni-Cu cladding grinding balls, and on the other hand, the use of these grinding balls for the hydrosilylation ball milling reaction of unsaturated compounds such as olefins, alkynes and carbonyl compounds.

[0010] To solve the above technical problems, the present invention provides a method for preparing Rh-Ni-Cu cladding grinding balls, comprising the following steps:

[0011] 1) Pretreatment of grinding balls:

[0012] The grinding balls are polished to remove surface dirt and oxide layers, then cleaned and dried (e.g., at 70±10℃ for about 1±0.2 hours) to obtain the treated grinding balls;

[0013] 2) Rh-Ni-Cu alloy material configuration:

[0014] Powdered Rh, Ni and Cu are mixed in a mixer to form alloy powder, which is then dried (i.e., the powder is dried before cladding, at 70±10℃ for about 1±0.2 hours) to obtain dry alloy powder.

[0015] In the alloy powder, the content of Rh is 3 wt%, the content of Ni is 62-82 wt%, and the content of Cu is 15-35 wt%.

[0016] 3) Grinding ball cladding:

[0017] The dried alloy powder obtained in step 2) is bonded to the surface of the treated grinding ball obtained in step 1) with an adhesive. After being dried with hot air (so that the adhesive is evaporated, for example, hot air at 80±10℃ for 30±5 minutes), it is preheated to 170~180℃ and then placed on the cladding worktable to perform laser cladding on the surface of the grinding ball to obtain a metal cladding layer grinding ball.

[0018] As an improvement to the preparation method of the Rh-Ni-Cu cladding layer grinding ball of the present invention, in step 3):

[0019] The laser cladding process parameters are as follows: laser power of 800-2000W (preferably 1000-1500W), spot diameter of 3-5mm (preferably 4mm), scanning speed of 5-7mm / s (preferably 6mm / s), overlap rate of 40-60% (preferably 50%), and powder feeding speed of 7-9g / min (preferably 8g / min).

[0020] The average thickness of the laser coating is 1.0–1.2 mm.

[0021] As a further improvement to the preparation method of the Rh-Ni-Cu cladding grinding ball of the present invention, in step 1):

[0022] The grinding balls are made of 303 stainless steel, 304 stainless steel, tungsten carbide or zirconium oxide, and the particle size of the grinding balls is 25mm to 45mm (spherical).

[0023] Polish the grinding ball with 200-500 grit sandpaper and clean it with pure water and ethanol.

[0024] As a further improvement to the preparation method of the Rh-Ni-Cu cladding grinding ball of the present invention, in step 3), each grinding ball is equipped with 10-35g of dried alloy powder.

[0025] As a further improvement to the preparation method of the Rh-Ni-Cu cladding layer grinding ball of the present invention,

[0026] The preferred formulation of the alloy powder in step 2) is: Rh 3wt%, Ni 77wt%, Cu 20wt%.

[0027] As a further improvement to the preparation method of the Rh-Ni-Cu cladding layer grinding ball of the present invention,

[0028] When the particle size of the grinding balls is 25 mm, each grinding ball is equipped with 10 to 13 g of dry alloy powder;

[0029] When the particle size of the grinding balls is 35mm, each grinding ball is equipped with 15-18g of dry alloy powder;

[0030] When the particle size of the grinding balls is 45 mm, each grinding ball is equipped with 30-35 g of dry alloy powder.

[0031] As a further improvement to the preparation method of the Rh-Ni-Cu cladding grinding ball of the present invention, the binder is prepared by mixing 502 glue and acetone at a volume ratio of 1:14-16, and the mass ratio of dry alloy powder to binder is 1:(1±0.1).

[0032] This invention also provides a hydrogenation method, using Rh-Ni-Cu cladding grinding balls prepared by any of the above methods as a catalyst, comprising the following steps:

[0033] Rh-Ni-Cu clad grinding balls as catalyst and reaction raw materials for hydrosilylation are loaded into a ball mill jar; the reaction raw materials consist of compounds containing Si-H bonds (organosilanes) and unsaturated substances (e.g., unsaturated hydrocarbons); the molar ratio of unsaturated substances to compounds containing Si-H bonds is 1:(1.2±0.1);

[0034] The mixture was ball-milled at room temperature for 5 to 10 hours (preferably 7 to 10 hours) under a reaction pressure of 0.1 to 1 MPa and a rotation speed of 700 to 1000 rpm. After the reaction was completed, the reaction mixture was removed from the ball mill jar, filtered, and the filtrate and filter cake were obtained separately. The filter cake was washed with ethanol to obtain a washing liquid. The washing liquid and filtrate were combined and then distilled to obtain the hydrosilylation product.

[0035] As an improvement to the hydrosilylation method of the present invention: a metal cladding grinding ball is prepared by using (300±20)g of dry alloy powder for every 1.0mol of unsaturated material.

[0036] Specifically, a 1.5L ball mill jar is filled with grinding balls containing 300±20g of dry alloy powder. The number of grinding balls is 10 to 30, specifically 10 (45mm), 20 (35mm), and 30 (25mm).

[0037] As an improvement to the hydrosilylation method of the present invention:

[0038] The unsaturated compound is any one of the following: pentene, hexene, heptenene, styrene, heptyne, octyne, phenylacetylene, propionaldehyde, butyraldehyde, benzaldehyde, acetone, butanone, acetophenone;

[0039] The compounds containing Si-H bonds are any of the following: dimethylchlorosilane, methyldichlorosilane, benzylsilane, diphenylsilane, trimethoxysilane, and triethoxysilane.

[0040] This invention prepares grinding balls with surface-coated metal catalysts and develops a ball milling process for downstream products of hydrosilylation. Its technical advantages are:

[0041] 1. This invention utilizes laser cladding technology to prepare a metal catalyst clad on the surface of a grinding ball. When used in a hydrosilylation reaction, this catalyst exhibits excellent catalytic performance, with high raw material reaction rate, stable catalytic performance, and easy collection and processing.

[0042] 2. The method of using metal powder directly as a catalyst to catalyze the hydrosilylation reaction of olefins and hydrogen-containing silanes can simplify the preparation of hydrosilylation catalysts and reduce the cost of the hydrosilylation reaction. Furthermore, the new process using mechanochemical synthesis methods is more in line with sustainable development requirements, enabling the hydrosilylation reaction to achieve near-atom economy and promoting green and efficient production of hydrosilylation reactions in the chemical industry.

[0043] In summary, this invention provides a method for the direct use of metal powder as a catalyst to catalyze the hydrosilylation reaction of olefins and hydrogen-containing silanes. This method simplifies the preparation of hydrosilylation catalysts and reduces the cost of the hydrosilylation reaction. Furthermore, the novel mechanochemical synthesis process promotes the green and efficient production of hydrosilylation reactions in the chemical industry. Detailed Implementation

[0044] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited thereto:

[0045] The metals Rh, Ni, and Cu in the alloy powder have a particle size of 25–50 μm and a spherical shape.

[0046] The products obtained in the following cases were verified to be correct through routine NMR analysis.

[0047] Example 1: A method for ball milling catalyzed hydrosilylation reaction, comprising the following steps:

[0048] 1) Pretreatment of grinding balls: Take 30 zirconia grinding balls with a diameter of 25mm and use 500-grit sandpaper to polish the surface of the zirconia grinding balls. The polishing should completely remove the surface dirt and oxide layer, that is, remove the oxide film on the surface of the grinding balls until there are no coarse scratches, the direction of the polishing marks is consistent and the surface is bright. After cleaning with ethanol, put them in a 70℃ drying oven for 1 hour to dry, and you will get polished grinding balls (treated grinding balls) for later use.

[0049] 2) Alloy powder material preparation:

[0050] An alloy powder was prepared with a weight percentage of 3 wt% Rh, 77 wt% Ni, and 20 wt% Cu.

[0051] Weigh the alloy powder and then mix it in a dry powder mixer for 3 hours to ensure that Rh, Ni and Cu are evenly mixed. Dry it at 70°C for about 1 hour (the purpose of drying is to remove any moisture that may be present in the alloy powder, so that it can be easily bonded to the grinding balls later) to obtain dry alloy powder; set aside for use.

[0052] 3) Grinding ball cladding:

[0053] Mix 502 glue and acetone evenly at a volume ratio of 1:15 to obtain the adhesive.

[0054] The 300g of dry alloy powder obtained in step 2) is mixed with an equal mass of binder to form a paste, and then evenly coated on the surface of the polished grinding ball obtained in step 1). It is then dried with hot air (80°C hot air for 30 minutes to evaporate the binder); thus obtaining a grinding ball coated with alloy powder.

[0055] After preheating the grinding ball coated with alloy powder to 160°C, it was fixed on the laser cladding stage. The laser cladding process parameters were set as follows: laser power of 1000W, spot diameter of 4mm, scanning speed of 6mm / s, overlap rate of 50%, and powder feeding speed of 8g / min. A Rh-Ni-Cu cladding layer with an average thickness of about 1mm was clad on the surface of the grinding ball. The resulting product was named the clad grinding ball.

[0056] 4) Ball milling reaction:

[0057] All the clad grinding balls obtained in step 3) were loaded into a ball mill jar (1.5L). The raw material consisting of 1.0 mol of pentene (1-pentene) and 1.2 mol of trimethoxysilane was added into the ball mill jar (i.e., the molar ratio of pentene to trimethoxysilane = 1:1.2). Mechanical ball milling was carried out for 8 hours at a pressure of 0.1 MPa and a speed of 1000 rpm.

[0058] After the reaction was complete, the reaction mixture was removed from the ball mill jar and filtered to obtain the filtrate. The solid obtained after filtration was washed three times with ethanol to obtain the washing liquid. The washing liquid and the filtrate were mixed and then distilled. The fraction collected at 175–185 °C was used to obtain n-pentyltrimethoxysilane.

[0059] The results showed that the pentene conversion rate was 86.7% and the selectivity of the product n-pentyltrimethoxysilane was 92.3%.

[0060]

[0061]

[0062] Note: n B The molar mass of pentene added to the reaction system is expressed in mol.

[0063] n B ' is the molar mass of pentene in the reaction system after the reaction, in mol;

[0064] n C ' is the molar mass (mol) of the product n-pentyltrimethoxysilane in the reaction system after the reaction.

[0065] Examples 2-4: Compared to Example 1, the ratio of Rh, Ni, and Cu in the alloy powder was changed, while the total amount of alloy powder remained unchanged; other operations were the same as in Example 1, resulting in Examples 2-4. The process parameters and reaction results are shown in Table 1.

[0066] Table 1

[0067]

[0068] Examples 5-6: Compared to Example 1, the particle size and quantity of the grinding balls were changed, while other operations were the same as in Example 1. The process parameters and reaction results are shown in Table 2.

[0069] Table 2

[0070]

[0071]

[0072] Examples 7-11: Compared to Example 1, the ball milling time in step 4) is changed, while other operations are the same as in Example 1. The process parameters and reaction results are shown in Table 3.

[0073] Table 3

[0074]

[0075] Examples 12-16: Compared to Example 1, the ball milling speed in step 4) is changed, while other operations are the same as in Example 1. The process parameters and reaction results are shown in Table 4.

[0076] Table 4

[0077]

[0078] Example 17 series: Alkene hydrosilylation reaction with different reactants, as detailed below:

[0079] Example 17-1: Compared to Example 1, the raw materials were changed to consist of 1.0 mol heptenene and 1.2 mol triethoxysilane, and the fraction was distilled at 80-90°C; the rest was the same as in Example 1.

[0080] The conversion rate of heptene was 92.6%, and the selectivity of the product n-heptyltriethoxysilane was 98.9%.

[0081] Example 17-2: Compared to Example 1, the raw materials were changed to consist of 1.0 mol of pentene and 1.2 mol of dimethylchlorosilane, and the fraction was distilled at 160-170°C; the rest was the same as in Example 1.

[0082] The conversion rate of pentene was 78.3%, and the selectivity of the product n-pentyldimethylchlorosilane was 97.7%.

[0083] Example 17-3: Compared to Example 1, the raw materials were changed to consist of 1.0 mol hepten and 1.2 mol methyl dichlorosilane, and the fraction was distilled at 200-210°C; the rest was the same as in Example 1.

[0084] The conversion rate of heptene was 82.6%, and the selectivity of the product n-heptylmethyldichlorosilane was 85.8%.

[0085] Examples 17-4: Compared to Example 1, the raw materials were changed to consist of 1.0 mol styrene and 1.2 mol dimethylchlorosilane, and the fraction was distilled at 50-60°C; the rest was the same as in Example 1.

[0086] The styrene conversion rate was 87.9%, and the selectivity of the product phenethyldimethylchlorosilane was 93.7%.

[0087] Examples 17-5: Compared to Example 1, the raw materials were changed to consist of 1.0 mol heptyne and 1.2 mol dimethylchlorosilane, and the fraction was distilled at 225-235°C; the rest was the same as in Example 1.

[0088] The conversion rate of heptyne was 95.7%, and the selectivity of the product heptenyldimethylchlorosilane was 97.8%.

[0089] Examples 17-6: Compared to Example 1, the raw materials were changed to consist of 1.0 mol of octyne and 1.2 mol of trimethoxysilane, and the fraction was distilled at 250-270°C; the rest was the same as in Example 1.

[0090] The conversion rate of octyne was 94.2%, and the selectivity of the product octenyltrimethoxysilane was 90.3%.

[0091] Examples 17-7: Compared to Example 1, the raw materials were changed to consist of 1.0 mol of phenylacetylene and 1.2 mol of dimethylchlorosilane, and the fraction was distilled at 78-88°C; the rest was the same as in Example 1.

[0092] The conversion rate of phenylacetylene was 93.2%, and the selectivity of the product styryldimethylchlorosilane was 94.6%.

[0093] Examples 17-8: Compared to Example 1, the raw materials were changed to consist of 1.0 mol of phenylacetylene and 1.2 mol of trimethoxysilane, and the fraction was distilled at 95-105°C; the rest was the same as in Example 1.

[0094] The conversion rate of phenylacetylene was 96.2%, and the selectivity of the product styryltrimethoxysilane was 92.3%.

[0095] Example 18 series: Aldehyde hydrosilylation reaction with different reactants, as detailed below:

[0096] Example 18-1: Compared with Example 1, the raw materials were changed to consist of 1.0 mol of propionaldehyde and 1.2 mol of trimethoxysilane, and the fraction was distilled at 137-147°C; the rest was the same as in Example 1.

[0097] The conversion rate of propionaldehyde was 93.2%, and the selectivity of the product propoxytrimethoxysilane was 94.5%.

[0098] Example 18-2: Compared to Example 1, the raw materials were changed to consist of 1.0 mol butyraldehyde and 1.2 mol triethoxysilane, and the fraction was distilled at 175-185°C; the rest was the same as in Example 1.

[0099] The conversion rate of butyraldehyde was 95.3%, and the selectivity of the product butoxytriethoxysilane was 96.2%.

[0100] Example 18-3: Compared with Example 1, the raw materials were changed to consist of 1.0 mol benzaldehyde and 1.2 mol benzylsilane, and the fraction was distilled at 180-190°C; the rest was the same as in Example 1.

[0101] The conversion rate of benzaldehyde was 97.5%, and the selectivity of the product benzoxyphenylsilane was 95.4%.

[0102] Examples 18-4: Compared to Example 1, the raw materials were changed to consist of 1.0 mol benzaldehyde and 1.2 mol triethoxysilane, and the fraction was distilled at 230-240°C; the rest was the same as in Example 1.

[0103] The conversion rate of benzaldehyde was 94.7%, and the selectivity of the product benzoxytriethoxysilane was 92.6%.

[0104] Example 19 series: Ketone hydrosilylation reaction with different reactants, as detailed below:

[0105] Example 19-1: Compared to Example 1, the raw materials were changed to consist of 1.0 mol of acetone and 1.2 mol of diphenylsilane, and the fraction was distilled at 180-190°C; the rest was the same as in Example 1.

[0106] The acetone conversion rate was 91.4%, and the selectivity of the product isopropoxydiphenylsilane was 95.2%.

[0107] Example 19-2: Compared to Example 1, the raw materials were changed to consist of 1.0 mol of butanone and 1.2 mol of trimethoxysilane, and the fraction was distilled at 235-245°C; the rest was the same as in Example 1.

[0108] The conversion rate of butanone was 92.5%, and the selectivity of the product trimethoxysec-butoxysilane was 93.1%.

[0109] Examples 19-3: Compared to Example 1, the raw materials were changed to consist of 1.0 mol of acetophenone and 1.2 mol of diphenylsilane, and the fraction was distilled at 155-165°C; the rest was the same as in Example 1.

[0110] The acetophenone conversion rate was 92.7%, and the selectivity of the product diphenyl-[(methoxyphenyl)methoxy]silane was 94.8%.

[0111] Example 20: The laser cladding process parameters in step 3) were modified as follows: laser power 800W, spot diameter 4mm, scanning speed 6mm / s, overlap rate 50%, powder feeding speed 8g / min, and the rest were the same as in Example 1. The results were: pentene conversion rate 70.2%, and product n-pentyltrimethoxysilane selectivity 83.4%.

[0112] Example 21: The laser cladding process parameters in step 3) were modified as follows: laser power 1500W, spot diameter 4mm, scanning speed 6mm / s, overlap rate 50%, powder feeding speed 8g / min, and the rest were the same as in Example 1. The results were: pentene conversion rate 80.9%, and product n-pentyltrimethoxysilane selectivity 89.7%.

[0113] Comparative Example 1: The "hot air drying" step 3) in Example 1 was omitted; instead, the coated grinding ball was preheated to 160°C and then fixed on the laser cladding stage; the rest was the same as in Example 1. The results were: pentene conversion rate 75.6%, and product n-pentyltrimethoxysilane selectivity 85.3%.

[0114] Finally, it should be noted that the above examples are merely some specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments and many variations are possible. All variations that can be directly derived or conceived by those skilled in the art from the disclosure of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A method for hydrosilylation, characterized in that: Using Rh-Ni-Cu cladding grinding balls as a catalyst, the process includes the following steps: Rh-Ni-Cu clad grinding balls, used as catalysts, and reaction raw materials for hydrosilylation were loaded into a ball mill jar. The reaction raw materials consisted of compounds containing Si-H bonds and unsaturated compounds. The molar ratio of unsaturated compounds to compounds containing Si-H bonds was 1:(1.2±0.1). Each 1.0 mol of unsaturated compound was mixed with (300±20) g of Rh-Ni-Cu clad grinding balls prepared from dry alloy powder. The reaction mixture was ball-milled at room temperature for 5 to 10 hours at a reaction pressure of 0.1 to 1 MPa and a rotation speed of 700 to 1000 rpm. After the reaction was completed, the reaction mixture was removed from the ball mill jar, filtered, and the filtrate and filter cake were obtained separately. The filter cake was washed with ethanol to obtain a washing liquid. The washing liquid and filtrate were combined and then distilled to obtain the hydrosilylation product. The preparation method of Rh-Ni-Cu cladding grinding balls includes the following steps: 1) Pretreatment of grinding balls: The grinding balls are polished to remove surface dirt and oxide layers, then cleaned and dried to obtain the treated grinding balls; 2) Rh-Ni-Cu alloy material configuration: Powdered Rh, Ni and Cu are mixed in a mixer to form alloy powder, which is then dried to obtain dry alloy powder. In the alloy powder, the content of Rh is 3 wt%, the content of Ni is 62-82 wt%, and the content of Cu is 15-35 wt%. 3) Grinding ball cladding: The dried alloy powder obtained in step 2) is bonded to the surface of the treated grinding ball obtained in step 1) with an adhesive. After being dried with hot air, it is preheated to 170-180°C and then placed on a cladding worktable to perform laser cladding on the surface of the grinding ball to obtain a metal cladding layer grinding ball.

2. The hydrosilylation method according to claim 1, characterized in that: The unsaturated compound is any one of the following: pentene, hexene, heptenene, styrene, heptyne, octyne, phenylacetylene, propionaldehyde, butyraldehyde, benzaldehyde, acetone, butanone, acetophenone; The compounds containing Si-H bonds are any of the following: dimethylchlorosilane, methyldichlorosilane, benzylsilane, diphenylsilane, trimethoxysilane, and triethoxysilane.

3. The hydrosilylation method according to claim 2, characterized in that... In step 3): The laser cladding process parameters are as follows: laser power of 800-2000W, spot diameter of 3-5mm, scanning speed of 5-7mm / s, overlap rate of 40-60%, and powder feeding speed of 7-9g / min.

4. The hydrosilylation method according to claim 3, characterized in that... In step 1): The grinding balls are made of 303 stainless steel, 304 stainless steel, tungsten carbide or zirconium oxide, and the particle size of the grinding balls is 25mm to 45mm. Polish the grinding ball with 200-500 grit sandpaper and clean it with pure water and ethanol.

5. The hydrosilylation method according to claim 4, characterized in that... In step 3), each grinding ball is equipped with 10-35g of dried alloy powder.

6. The hydrosilylation method according to claim 5, characterized in that: The alloy powder formulation in step 2) is: Rh 3wt%, Ni 77wt%, Cu 20wt%.

7. The hydrosilylation method according to any one of claims 1 to 6, characterized in that: When the particle size of the grinding balls is 25 mm, each grinding ball is equipped with 10 to 13 g of dry alloy powder; When the particle size of the grinding balls is 35mm, each grinding ball is equipped with 15-18g of dry alloy powder; When the particle size of the grinding balls is 45 mm, each grinding ball is equipped with 30-35 g of dry alloy powder.

8. The hydrosilylation method according to any one of claims 1 to 6, characterized in that: The adhesive is prepared by mixing 502 glue and acetone in a volume ratio of 1:14-16; the mass ratio of dry alloy powder to adhesive is 1:(1±0.1).

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