A method for preparing silicone microspheres from methyltrimethoxysilane high boiler

Abstract

The application discloses a method for preparing organic silicon microspheres from methyltrimethoxysilane high-boiling substances, realizes efficient utilization and continuous production through innovative pretreatment, hydrolysis and polymerization process, and provides an efficient, economical and environmentally-friendly solution for comprehensive utilization of methyltrimethoxysilane high-boiling substances. The main steps are as follows: (1) pretreatment of high-boiling substances; the by-product high-boiling substances in the production process of methyltrimethoxysilane are mixed with methanol and methyltrimethoxysilane to form material A, then instrument gas is blown in, a treating agent is added, and reaction is carried out under specific temperature and pressure conditions, and then excess impurities are removed through multiple filters; (2) the purified material is mixed with deionized water in a certain proportion, and hydrolysis reaction is completed under the catalysis of 98% mass fraction sulfuric acid, then the material is preliminarily mixed with a prepared lye in a mixer and is sent into a polymerization kettle to complete polymerization reaction and obtain a polymerization liquid; and (3) the polymerization liquid is filtered, dried and crushed to obtain pure white organic silicon microspheres.

Description

Technical Field

[0001] This invention belongs to the field of chemical production technology, specifically relating to a method and apparatus for preparing organosilicon microspheres from methyltrimethoxysilane high-boiling-point compounds. Background Technology

[0002] Methyltrimethoxysilane, an important organosilicon compound, is increasingly widely used in many fields, including the rubber, coatings, and adhesives industries. Its production process can be simplified to the reaction of methyltrichlorosilane with methanol via alcoholysis, followed by neutralization and distillation. However, in this process, the unavoidable presence of trace amounts of moisture in the raw methanol leads to a series of side reactions and the formation of polymers. These polymers deposit during the deweighting process, ultimately forming high-boiling-point substances. These high-boiling-point substances mainly contain unreacted methanol, methyltrimethoxysilane, and methyltrimethoxysilane polymers, posing a significant flammability hazard.

[0003] Currently, the main methods for treating these high-boiling-point substances include cracking and direct incineration. While cracking can recover high-boiling-point substances, its high cost makes it unsuitable for large-scale production. Direct incineration, although simple to operate and inexpensive, cannot effectively utilize high-boiling-point substances and causes environmental pollution. Therefore, how to effectively treat the high-boiling-point substances generated during the production of methyltrimethoxysilane, while reducing costs and minimizing environmental impact, has become a key issue in this field. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a method for preparing organosilicon microspheres from methyltrimethoxysilane high-boiling-point compounds, which effectively solves the problems described above.

[0005] A method for preparing organosilicon microspheres from methyltrimethoxysilane high-boiling-point compounds includes the following steps:

[0006] (1) Pretreatment of high-boiling substances: High-boiling substances produced by the production process of methyltrimethoxysilane are used to form material A by mixing with methanol and methyltrimethoxysilane. Then, instrument gas is blown in and treatment agent is added to react. After that, excess impurities are removed by multi-stage filters to obtain purified material.

[0007] (2) The purified material is mixed with deionized water in a certain proportion and hydrolyzed under the catalysis of sulfuric acid with a mass fraction of 98% or higher. Then it is initially mixed with the pre-prepared alkaline solution in a mixer and sent to the polymerization reactor to complete the polymerization reaction to obtain the polymer liquid.

[0008] (3) The polymer solution can be filtered, dried and pulverized to obtain pure white organosilicon microspheres.

[0009] The high-boiling byproduct in the production process of methyltrimethoxysilane is a byproduct of the reaction of methyltrichlorosilane with methanol to produce methyltrimethoxysilane. During this process, some methyltrimethoxysilane undergoes condensation polymerization under high temperature and alkaline conditions to form polymers with uneven degrees of polymerization, which are discharged as high-boiling byproducts in the production process of methyltrimethoxysilane.

[0010] As reported in the applicant's relevant patent CN113861233 A, the process for preparing methyltrimethoxysilane also yields some byproducts, namely high-boiling substances, during the process of obtaining crude methyltrimethoxysilane. These high-boiling substances are produced when methanol and solvent are added to a mixer in a certain proportion and mixed evenly. Then, methyltrichlorosilane and the mixture in the mixer are simultaneously introduced into a Venturi mixer in a certain proportion. The two are fully mixed and react. During this reaction, some high-boiling substances are generated. These high-boiling substances are then separated by a distillation column to obtain methyltrimethoxysilane high-boiling substances.

[0011] The content of each component in material A in step (1) is adjusted as follows: 2%~5% methanol, 20%~30% methyltrimethoxysilane, and 65%~78% high-boiling by-products of methyltrimethoxysilane production.

[0012] In this invention, material A contains high-boiling-point substances with uneven polymerization, which easily leads to stratification. Furthermore, during the production of methyltrimethoxysilane, production parameters fluctuate within a certain range, causing the content of high-boiling-point substances to vary. To achieve a more balanced composition in raw material A, a certain amount of methanol is added as a solvent, resulting in more uniform mixing of the high-boiling-point substances. Adding a certain amount of methyltrimethoxysilane avoids the problem of uncontrollable content of byproduct high-boiling-point substances and controls the stability of the raw material.

[0013] After material A is added to the pretreatment vessel, instrument gas is continuously introduced during the stirring process to bubble it, and the oxygen in the instrument gas is used to oxidize some of the substances in material A; the water content in the instrument gas is <50ppm; then the treatment agent is added to the pretreatment vessel, the amount of which is 0.5%~1% of material A, and the temperature of the pretreatment vessel is controlled at 70~80℃, the pressure is 0.1Mpa~0.15Mpa, and the reaction time is controlled at 60min~90min.

[0014] The treatment agent is one of the following substances: sodium methoxide, sodium ethoxide, aluminum trichloride, ferric trichloride, etc.

[0015] After passing through the pretreatment vessel, material A is passed through a primary filter for initial filtration. The filter medium is quartz sand to remove any particulate crystals or mechanical impurities that may appear in the solution. After initial filtration, material A enters a secondary filter for fine filtration. The filter medium is a microporous membrane, ion exchange resin, etc., to further reduce the content of fine particles and improve the transparency of material A. In step (2), material A is transferred to a hydrolysis vessel. At the same time, pure water and sulfuric acid with a mass fraction of 98% are added from the top to the bottom of the hydrolysis vessel. The mass ratio is material A: water: sulfuric acid = 100: 500~800: 0.01~0.05. The temperature of the hydrolysis vessel is controlled at 60~75℃. The pre-prepared alkaline solution contains water, surfactant, and alkaline catalyst. The surfactant is one or more of nonylphenol polyoxyethylene ether, polyoxyethylene fatty alcohol ether, sulfonates, etc.; the alkaline catalyst is one of sodium hydroxide solution, ammonia, potassium hydroxide solution, alkanolamine, etc. The mass ratio of each substance is: water:surfactant = 100: 0.05~2. The molar concentration of the alkaline catalyst is controlled at 0.1mol / L~0.35mol / L, and the amount added is 5~9% of the mass of hydrolyzed material A.

[0016] All water used in this invention is deionized water.

[0017] The treated material A is fed into the hydrolysis reactor using a bottom-feed method. The reactor has one or more openings on its side, allowing the liquid to overflow into a transfer tank. The mixed solution remains in the reactor for 30-45 minutes (i.e., the hydrolysis reaction time is 30-45 minutes). The hydrolyzed solution is then mixed with a pre-prepared alkaline solution at a mass ratio of hydrolysate:prepared alkali solution = 1:1-1.5 in a mixer for initial mixing. Next, the material is fed from the bottom of the polymerization reactor, where it is further mixed uniformly under stirring. The polymerization reactor also has one or more openings on its side, allowing the polymerization liquid to overflow into a settling tank, ensuring the polymerization liquid remains in the reactor for 15-25 minutes (i.e., the polymerization reaction time is 15-25 minutes).

[0018] In step (3), after the polymerization liquid is placed in a settling tank for 1-2 hours, the polymer liquid is centrifuged and filtered to separate the solid material. The solid material is then rapidly obtained by flash drying and air jet milling, resulting in a particle size distribution of 1-20 μm, a refractive index of 1.41-1.43, and a bulk density of 0.4-0.6 g / cm³. 3 The product consists of pure white organosilicon microspheres with a yield of >80%.

[0019] The advantages of this invention compared to the prior art are:

[0020] 1. Efficient utilization of by-product resources: Most organosilicon microspheres are prepared using high-purity methylalkoxysilane. This invention makes full use of the high-boiling by-products generated during the production of methyltrimethoxysilane to prepare organosilicon microspheres, which not only reduces the requirements and costs of raw materials, but also significantly reduces the processing costs of high-boiling by-products and greatly enhances their utilization value.

[0021] 2. Economical and efficient pretreatment: The application of instrument-controlled bubbling technology not only promotes the reaction of unoxidized substances in high-boiling-point substances but also reduces process costs compared to directly using dry oxygen. Simultaneously, by adding any one of the following treatment agents—sodium methoxide, sodium ethoxide, aluminum trichloride, or ferric chloride—some unsaturated substances and chloride ions in the high-boiling-point substances are effectively removed, avoiding agglomeration caused by rapid hydrolysis and ensuring the quality of the organosilicon microspheres.

[0022] 3. Precise particle size control: By adjusting the component ratio in the high-boiling point, this method can effectively control the size and distribution of organosilicon microspheres, producing microspheres with uniform size to meet the stringent requirements of different application fields.

[0023] 4. High impurity removal efficiency: The secondary filter uses microporous filter membranes, ion exchange resins and other filter media, which can effectively remove fine impurities and some salt substances from high-boiling substances, reduce the conductivity of the solution, prevent abnormal agglomeration due to excessive conductivity during the condensation stage, and improve the quality of organosilicon microspheres.

[0024] 5. High-efficiency production equipment: Hydrolysis and polymerization reactions are carried out through overflow mixing, increasing the contact time between the catalyst and materials, achieving continuous production, and reducing power consumption. By appropriately adjusting the catalyst concentration, the abnormal enlargement and agglomeration of organosilicon microspheres due to excessively high local concentrations during the mixing of hydrolysate and alkaline catalyst are avoided, further ensuring the consistency and stability of the organosilicon microspheres. Attached Figure Description

[0025] Figure 1 This is a particle size distribution diagram of organosilicon microspheres in Example 2.

[0026] Figure 2 This is a scanning electron microscope image of the organosilicon microspheres in Example 3.

[0027] Figure 3 This is a microsphere size distribution diagram under abnormal conditions in Example 4.

[0028] Figure 4 This is an electron microscopy scan of the microspheres under abnormal conditions in Example 4. Detailed Implementation

[0029] Example 1

[0030] (1) A high-boiling-point byproduct from the production of methyltrimethoxysilane was used to form a methyltrimethoxysilane composite high-boiling-point compound after being mixed with methanol and methyltrimethoxysilane. The content distribution after mixing was: 2.3% methanol, 21% methyltrimethoxysilane, and 76.7% methyltrimethoxysilane high-boiling-point compound. 100 parts of the mixed methyltrimethoxysilane high-boiling-point compound were introduced into a treatment vessel. A dried instrument gas was inserted below the liquid surface of the methyltrimethoxysilane composite high-boiling-point compound to perform bubbling. 0.6 parts of sodium methoxide were added to the treatment vessel. The reaction temperature was controlled at 75°C, the pressure at 0.1 MPa, and the reaction time at 60 min to remove unsaturated alkanes and a small amount of chlorine.

[0031] (2) The methyltrimethoxysilane composite high-boiling material after pretreatment is passed into the primary filter for initial filtration, and then the methyltrimethoxysilane composite high-boiling material after initial filtration is passed into the secondary processor. The filter material of the secondary processor is a microporous membrane to remove fine crystals, sodium chloride and other fine impurities in the solution.

[0032] (3) After the pretreatment, the methyltrimethoxysilane composite high boiling point is transferred to the hydrolysis kettle, 600 parts of deionized water and 0.02 parts of sulfuric acid with a mass fraction of 98% are added, the temperature of the hydrolysis kettle is controlled at 60℃, the hydrolysis reaction is carried out, the solution residence time is kept at 30min, and then overflow into the transfer tank;

[0033] (4) Take 553 parts of deionized water, 11 parts of nonylphenol polyoxyethylene ether, and 36 parts of 0.3 mol / L sodium hydroxide solution to prepare 700 parts of pre-prepared alkaline solution. Mix the pre-prepared alkaline solution with the hydrolyzed methyltrimethoxysilane material through a mixer, and then enter the reactor from the bottom of the polymerization kettle. Maintain a residence time of 15 min, and then overflow into a settling tank. Let it stand for 1.5 h, separate the solid material, and then dry and pulverize it to obtain a particle size D50=6.89μm, refractive index 1.42, and bulk density of 0.45g / cm³. 3 The pure white organosilicon microspheres were obtained, with a yield of 82.1%.

[0034] Example 2

[0035] (1) A high-boiling-point byproduct from the production of methyltrimethoxysilane was used to form a methyltrimethoxysilane composite high-boiling-point compound after being mixed with methanol and methyltrimethoxysilane. The content distribution after mixing was: 5% methanol, 25% methyltrimethoxysilane, and 70% methyltrimethoxysilane high-boiling-point compound. 100 parts of the mixed methyltrimethoxysilane high-boiling-point compound were introduced into a treatment vessel. A dried instrument gas was inserted below the liquid surface of the methyltrimethoxysilane composite high-boiling-point compound to perform bubbling. 0.6 parts of sodium methoxide were added to the treatment vessel. The reaction temperature was controlled at 75°C, the pressure at 0.1 MPa, and the reaction time at 60 min to remove unsaturated alkanes and a small amount of chlorine.

[0036] (2) The methyltrimethoxysilane composite high-boiling material after pretreatment is passed into the primary filter for initial filtration, and then the methyltrimethoxysilane composite high-boiling material after initial filtration is passed into the secondary processor. The filter material of the secondary processor is a microporous membrane to remove fine crystals, sodium chloride and other fine impurities in the solution.

[0037] (3) After the pretreatment, the methyltrimethoxysilane composite high boiling point is transferred to the hydrolysis kettle, 600 parts of deionized water and 0.02 parts of sulfuric acid with a mass fraction of 98% are added, the temperature of the hydrolysis kettle is controlled at 60℃, the hydrolysis reaction is carried out, the solution residence time is kept at 30min, and then overflow into the transfer tank;

[0038] (4) Take 553 parts of deionized water, 11 parts of nonylphenol polyoxyethylene ether, and 36 parts of 0.3 mol / L sodium hydroxide solution to prepare 700 parts of pre-prepared alkaline solution. Mix the pre-prepared alkaline solution with the hydrolyzed methyltrimethoxysilane material through a mixer, and then enter the reactor from the bottom of the polymerization kettle. Maintain a residence time of 15 min, and then overflow into a settling tank. Let it stand for 1.5 h, separate the solid material, and then dry and pulverize it to obtain a particle size D50=4.68μm, refractive index 1.42, and bulk density of 0.48g / cm³. 3 The pure white organosilicon microspheres were obtained, with a yield of 83.2%.

[0039] Example 3

[0040] (1) A high-boiling-point byproduct from the production of methyltrimethoxysilane was used to form a methyltrimethoxysilane composite high-boiling-point compound after being mixed with methanol and methyltrimethoxysilane. The content distribution after mixing was: 5% methanol, 25% methyltrimethoxysilane, and 70% methyltrimethoxysilane high-boiling-point compound. 100 parts of the mixed methyltrimethoxysilane high-boiling-point compound were introduced into a treatment vessel. A dried instrument gas was inserted below the liquid surface of the methyltrimethoxysilane composite high-boiling-point compound to perform bubbling. 0.5 parts of ferric chloride were added to the treatment vessel. The reaction temperature was controlled at 75°C, the pressure at 0.1 MPa, and the reaction time at 60 min to remove unsaturated alkanes and a small amount of chlorine.

[0041] (2) The methyltrimethoxysilane composite high-boiling material after pretreatment is passed into the primary filter for initial filtration, and then the methyltrimethoxysilane composite high-boiling material after initial filtration is passed into the secondary processor. The filter material of the secondary processor is a microporous membrane to remove fine crystals, sodium chloride and other fine impurities in the solution.

[0042] (3) After the pretreatment, the methyltrimethoxysilane composite high boiling point is transferred to the hydrolysis kettle, 600 parts of deionized water and 0.02 parts of sulfuric acid with a mass fraction of 98% are added, the temperature of the hydrolysis kettle is controlled at 60℃, the hydrolysis reaction is carried out, the solution residence time is kept at 30min, and then overflow into the transfer tank;

[0043] (4) Take 803 parts of deionized water, 16 parts of nonylphenol polyoxyethylene ether, and 81 parts of 0.3 mol / L sodium hydroxide solution to prepare 900 parts of pre-prepared alkaline solution. Mix the pre-prepared alkaline solution with the hydrolyzed methyltrimethoxysilane material through a mixer, and then enter the reactor from the bottom of the polymerization kettle. Maintain a residence time of 15 min, and then overflow into a settling tank. Let it stand for 1.5 h, separate the solid material, and then dry and pulverize it to obtain a particle size D50=3.25 μm, refractive index 1.43, and bulk density of 0.58 g / cm³. 3 The pure white organosilicon microspheres were obtained, with a yield of 80.5%.

[0044] Example 4

[0045] (1) A high-boiling-point byproduct from the production of methyltrimethoxysilane was used to form a methyltrimethoxysilane composite high-boiling-point compound after being mixed with methanol and methyltrimethoxysilane. The content distribution after mixing was: 5% methanol, 25% methyltrimethoxysilane, and 70% methyltrimethoxysilane high-boiling-point compound. 100 parts of the mixed methyltrimethoxysilane high-boiling-point compound were introduced into a treatment vessel. A dried instrument gas was inserted below the liquid surface of the methyltrimethoxysilane composite high-boiling-point compound to perform bubbling. 0.5 parts of ferric chloride were added to the treatment vessel. The reaction temperature was controlled at 75°C, the pressure at 0.1 MPa, and the reaction time at 60 min to remove unsaturated alkanes and a small amount of chlorine.

[0046] (2) The methyltrimethoxysilane composite high-boiling-point substance after pretreatment in the pretreatment kettle is used directly without filtration.

[0047] (3) After pretreatment but not filtered, the methyltrimethoxysilane complex high boiling point was transferred to a hydrolysis reactor, 600 parts of deionized water and 0.02 parts of sulfuric acid with a mass fraction of 98% were added, the temperature of the hydrolysis reactor was controlled at 60°C, and the hydrolysis reaction was carried out. The solution residence time was kept for 30 minutes, and then it was overflowed into a transfer tank.

[0048] (4) Take 803 parts of deionized water, 16 parts of nonylphenol polyoxyethylene ether, and 81 parts of 0.3 mol / L sodium hydroxide solution to prepare 900 parts of pre-alkaline solution. Mix the pre-alkaline solution with the hydrolyzed material of methyltrimethoxysilane through a mixer and then enter the reactor from the bottom of the polymerization kettle. Maintain the residence time for 15 min and then overflow into the settling tank. Settle for 1.5 h and separate the solid material. Some organosilicon microspheres adsorb onto the surface of the impurities with the impurities as the core, forming large particles and agglomeration. After drying and pulverizing, the organosilicon microspheres are obtained with uneven particle size, particle size D50 > 15 μm, and organosilicon microsphere yield of 70.6%.

[0049] Example 5

[0050] (1) The high-boiling byproduct of the production of methyltrimethoxysilane is used directly as raw material without adding an appropriate amount of methanol or methyltrimethoxysilane. 100 parts of the high-boiling methyltrimethoxysilane are passed into the treatment vessel. The dried instrument gas is inserted below the liquid surface of the methyltrimethoxysilane composite high-boiling substance and bubbled. 0.5 parts of ferric chloride are added to the treatment vessel. The reaction temperature is controlled at 75°C, the pressure is 0.1 MPa, and the reaction time is 60 min to remove unsaturated alkanes and a small amount of chlorine.

[0051] (2) The high-boiling-point methyltrimethoxysilane is passed into the primary filter for initial filtration, and then the high-boiling-point methyltrimethoxysilane after initial filtration is passed into the secondary processor. The filter material of the secondary processor is a microporous membrane to remove fine crystals, sodium chloride and other fine impurities in the solution.

[0052] (3) Transfer the treated methyltrimethoxysilane high-boiling material to a hydrolysis reactor, add 800 parts of deionized water and 0.05 parts of 98% sulfuric acid, control the temperature of the hydrolysis reactor at 60°C, carry out the hydrolysis reaction, keep the solution residence time at 30 min, and then overflow into a transfer tank. During the hydrolysis reaction, a semi-transparent film appears on the surface of the liquid.

[0053] (4) Take 803 parts of deionized water, 16 parts of nonylphenol polyoxyethylene ether, and 81 parts of 0.3 mol / L sodium hydroxide solution to prepare 900 parts of pre-prepared alkaline solution. Mix the pre-prepared alkaline solution with the hydrolyzed methyltrimethoxysilane material through a mixer, and then enter the reactor from the bottom of the polymerization kettle. Maintain a residence time of 15 min, and then overflow into a settling tank. Let it stand for 1.5 h, separate the solid material, and then dry and pulverize it to obtain a particle size D50=12.81μm, refractive index 1.41, and bulk density of 0.41g / cm³. 3 The light yellow organosilicon microspheres were obtained, with a yield of 68.6%.

[0054] Example 6

[0055] (1) A high-boiling-point byproduct from the production of methyltrimethoxysilane was used to form a methyltrimethoxysilane composite high-boiling-point compound after being mixed with methanol and methyltrimethoxysilane. The content distribution after mixing was: 5% methanol, 25% methyltrimethoxysilane, and 75% methyltrimethoxysilane high-boiling-point compound. 100 parts of the mixed methyltrimethoxysilane high-boiling-point compound were introduced into a treatment vessel. A dried instrument gas was inserted below the liquid surface of the methyltrimethoxysilane composite high-boiling-point compound for bubbling operation. No treatment agent was added to the treatment vessel. The reaction temperature was controlled at 75°C, the pressure at 0.1 MPa, and the reaction time at 60 min.

[0056] (2) The methyltrimethoxysilane composite high-boiling-point substance without treatment agent is passed into the first-stage filter for initial filtration, and then the methyltrimethoxysilane composite high-boiling-point substance after initial filtration is passed into the second-stage processor. The filter material of the second-stage processor is a microporous membrane to remove fine crystals, sodium chloride and other fine impurities in the solution.

[0057] (3) Transfer the methyltrimethoxysilane complex high boiling point to a hydrolysis reactor, add 800 parts of deionized water and 0.05 parts of sulfuric acid with a mass fraction of 98%, control the temperature of the hydrolysis reactor at 60℃, carry out the hydrolysis reaction, keep the solution residence time at 30min, and then overflow into the transfer tank. Oily substances float on the surface of the liquid, and the solution is yellowish overall.

[0058] (4) Take 803 parts of deionized water, 16 parts of nonylphenol polyoxyethylene ether, and 81 parts of 0.3mol / L sodium hydroxide solution to prepare 900 parts of pre-prepared alkaline solution. Mix the pre-prepared alkaline solution with the hydrolyzed material of methyltrimethoxysilane through a mixer and then enter the reactor from the bottom of the polymerization kettle. Maintain a residence time of 15 minutes and then overflow into the settling tank. Settle for 1.5 hours. Yellow crystalline substance appears at the bottom of the settling tank, along with some hard blocky solids. Separate the solid substance, and then dry and crush it to obtain an irregularly shaped, yellow or even brown powder.

Claims

1. A method for preparing organosilicon microspheres from a high-boiling-point methyltrimethoxysilane, characterized in that, Includes the following steps: (1) The high-boiling by-product of the methyltrimethoxysilane production process is mixed with methanol and methyltrimethoxysilane to form material A. Then, instrument gas is blown in and a treatment agent is added to react. After that, excess impurities are removed by a secondary filter to obtain the purified material. After material A is put into the pretreatment vessel, instrument gas is continuously introduced during the stirring process to bubble, and the oxygen in the instrument gas is used to oxidize some of the substances in material A. The treatment agent includes any one of sodium methoxide, sodium ethoxide, aluminum trichloride, and ferric chloride. After passing through the pretreatment vessel, material A is passed into the primary filter for initial filtration, with quartz sand as the filter medium; after initial filtration, material A enters the secondary filter for fine filtration, with microporous filter membrane and ion exchange resin as the filter medium. (2) The purified material is mixed with water and hydrolyzed under sulfuric acid catalysis. Then it is initially mixed with pre-prepared alkali solution in a mixer and sent to a polymerization reactor to complete the polymerization reaction to obtain a polymer solution. (3) The polymer solution can be filtered, dried and pulverized to obtain pure white organosilicon microspheres.

2. The method for preparing organosilicon microspheres from methyltrimethoxysilane high-boiling-point compounds according to claim 1, characterized in that, The high-boiling byproduct in the production of methyltrimethoxysilane is a byproduct of the alcoholysis reaction of methyltrichlorosilane with methanol to produce methyltrimethoxysilane. During this process, some methyltrimethoxysilane undergoes condensation polymerization under high temperature and alkaline conditions to form polymers with uneven polymerization degrees. This polymer is discharged as a high-boiling byproduct in the production of methyltrimethoxysilane. The high-boiling byproduct is mixed with methanol and methyltrimethoxysilane to form material A in step (1).

3. The method for preparing organosilicon microspheres from methyltrimethoxysilane high-boiling-point compounds according to claim 2, characterized in that, The content of each component is adjusted as follows: 2%~5% methanol, 20%~30% methyltrimethoxysilane, and 65%~78% high-boiling by-products of methyltrimethoxysilane production.

4. The method for preparing organosilicon microspheres from methyltrimethoxysilane high-boiling-point compound according to claim 1, characterized in that, The water content in the instrument air is <50ppm; the dosage of the treatment agent is 0.5wt%~1wt% of material A.

5. The method for preparing organosilicon microspheres from methyltrimethoxysilane high-boiling-point compounds according to claim 1, characterized in that, In step (1), the temperature is maintained at 70~80℃, the pressure is 0.1MPa~0.15MPa, and the reaction time is controlled at 60min~90min.

6. The method for preparing organosilicon microspheres from methyltrimethoxysilane high-boiling-point compounds according to claim 1, characterized in that, Step (2) The mass ratio of purified material to water to sulfuric acid is 100:500~800:0.01~0.05, and the sulfuric acid is sulfuric acid with a mass fraction ≥98%; The hydrolysis reaction temperature is 60~75℃.

7. The method for preparing organosilicon microspheres from methyltrimethoxysilane high-boiling-point compound according to claim 1, characterized in that, The pre-prepared alkali solution contains water, surfactants, and alkali catalysts; The surfactant is one or more of nonylphenol polyoxyethylene ether, polyoxyethylene fatty alcohol ether, and sulfonated substances; The alkaline catalyst is one of the following: sodium hydroxide solution, ammonia water, potassium hydroxide solution, or an alcohol amine.

8. The method for preparing organosilicon microspheres from methyltrimethoxysilane high-boiling-point compound according to claim 7, characterized in that, The mass ratio of pure water to surfactant is 100:0.05~2, and the molar concentration of alkaline catalyst is controlled at 0.1mol / L~0.35mol / L; The amount of pre-prepared alkali solution added is 5-9% of the mass of hydrolyzed material A.

9. The method for preparing organosilicon microspheres from methyltrimethoxysilane high-boiling-point compounds according to claim 1, characterized in that, The purified material is fed into the hydrolysis reactor using a bottom-feed method. Water and sulfuric acid are added, and the hydrolysis time in the reactor is 30-45 minutes. The hydrolysis reactor has one or more openings on its side to allow the hydrolyzed liquid to overflow into a transfer tank. The hydrolyzed solution and pre-prepared alkali catalyst are fed into a mixer at a mass ratio of hydrolysate: pre-prepared alkali solution = 1:1-1.5 for initial mixing. Then, the material is fed from the bottom of the polymerization reactor and mixed evenly with stirring. The polymerization reactor also has one or more openings on its side to allow the polymerization liquid to overflow into a settling tank, ensuring the polymerization liquid remains in the reactor for 15-25 minutes.

10. Organosilicon microspheres prepared from the methyltrimethoxysilane high-boiling material obtained by the method according to any one of claims 1-9, characterized in that, The prepared organosilicon microspheres have a particle size distribution of 1–20 μm, a refractive index of 1.41–1.43, and a bulk density of 0.4–0.6 g / cm³. 3 The product consists of pure white organosilicon microspheres with a yield of >80%.

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