Synthesis method of a large spherical polysiloxane

Abstract

The present invention relates to the technical field of polysiloxane synthesis. In order to solve the problem that the synthesis and purification processes of existing large spherical polysiloxanes are complex and time-consuming, a method for synthesizing large spherical polysiloxanes is provided. Using a fully capped double-decked polyhedral oligomeric silsesquioxane with silicon-hydrogen bonds on both sides as a raw material, reacting in an organic solvent under the action of a catalyst to obtain large spherical polysiloxanes. The present invention uses a fully capped double-decked polyhedral oligomeric silsesquioxane with silicon-hydrogen bonds on both sides as a raw material to synthesize large spherical polysiloxanes, and the yield can reach 60-95%. It has the advantages of mild reaction conditions, low energy consumption, high efficiency, and simple and easy product purification process.

Description

Technical Field

[0001] The present invention relates to the technical field of polysiloxane synthesis, and particularly relates to a method for synthesizing large spherical polysiloxane. Background Art

[0002] Polysiloxane is a kind of polymer with a repeating Si-O bond as the main chain and organic groups directly connected to silicon atoms. Its general formula is [R n SiO (4-n) / 2 m , where R represents an organic group, such as methyl, phenyl, etc.; n is the number of organic groups connected to the silicon atom (between 1 and 3); m is the degree of polymerization (m is not less than 2). Polysiloxane was historically called "silicone", and currently silicone also appears in some occasions, such as in product catalogs. In China, it is customary to collectively call silane monomers and polysiloxanes organic silicon compounds, and call polysiloxane liquid silicone oil, polysiloxane rubber silicone rubber, and polysiloxane resin silicone resin. Its commercialized products include: silicone oil, organosilicon cyclic body, silicone rubber, silicone resin, etc. Polysiloxane has very good heat insulation effect and plays an important role in the aviation field.

[0003] Large spherical polysiloxane can be used in the fields of catalyst carriers, drug delivery, polymer additives, etc. In the prior art, large spherical polysiloxane is generally synthesized through an emulsion polymerization process, and there are problems of complex and time-consuming synthesis and purification processes in synthesizing large spherical polysiloxane through the emulsion polymerization process.

[0004] The Chinese patent document discloses "a method for synthesizing catenane-like polysiloxane", and the application publication number is CN105330865A. This invention uses small cyclic siloxane and water as raw materials and reacts in an organic solvent under the action of a metal catalyst to synthesize catenane-like polysiloxane. However, this synthesis method will destroy the framework structure of polyhedral oligomeric silsesquioxane and is not suitable for the preparation of large spherical polysiloxane. Summary of the Invention

[0005] In order to overcome the problems of complex and time-consuming synthesis and purification processes in the existing synthesis of large spherical polysiloxane, the present invention provides a method for synthesizing large spherical polysiloxane with mild reaction conditions, low energy consumption, high efficiency, and simple and easy product purification process.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for synthesizing large spherical polysiloxane uses a fully end-capped double-decked polyhedral oligomeric silsesquioxane with silicon-hydrogen bonds on both sides as a raw material, reacts in an organic solvent under the action of a catalyst to obtain large spherical polysiloxane; the structural formula of the fully end-capped double-decked polyhedral oligomeric silsesquioxane with silicon-hydrogen bonds on both sides is as follows:​

[0008]

[0009] Wherein, R and R' are each independently selected from one of hydrogen, alkyl, alkenyl, alkynyl, aryl, epoxy group, ester group, sulfonic acid group, carboxyl group, nitrile group, haloalkyl, haloalkenyl, and haloalkynyl.

[0010] The reaction mechanism of the present invention is hydrogen transfer isomerization polymerization, that is, the silicon-hydrogen bond causes isomerization polymerization through the hydrogen transfer process, so that a large spherical polysiloxane composed of polyhedral oligomeric silsesquioxane is obtained while retaining the framework structure of the polyhedral oligomeric silsesquioxane.

[0011] The reaction route is as follows:

[0012]

[0013] Preferably, the mass ratio of the fully capped double-decked polyhedral oligomeric silsesquioxane with silicon-hydrogen bonds on both sides to the catalyst is 1:(0.0001 - 0.1).

[0014] The addition amount of the catalyst is crucial and must be strictly controlled. If the addition amount of the catalyst is too low, the reaction cannot proceed or the yield is too low; if the addition amount of the catalyst is too high, crosslinking will occur.

[0015] Preferably, the catalyst is selected from one of the simple substances or corresponding compounds of boron, aluminum, gallium, indium, thallium, potassium, sodium, iron, cobalt, nickel, ruthenium, rhodium, platinum, palladium, osmium, iridium, gold, silver, copper, tin, zinc, titanium, zirconium, chromium, manganese, and lanthanide elements.

[0016] Preferably, the organic solvent is selected from one of alkanes, aromatic hydrocarbons, ethers, and ketones. The above types of organic solvents have the characteristic of similar polarity to the selected raw materials and products, and can effectively dissolve the raw materials and products.

[0017] Preferably, the organic solvent is selected from one of n-hexane, cyclohexane, toluene, diethyl ether, n-butyl ether, tetrahydrofuran, 1,4-dioxane, acetone, cyclohexanone, methyl isobutyl ketone, and ethyl acetate. The amount of the organic solvent used is the amount that can dissolve the solute.

[0018] Preferably, the reaction temperature is controlled at 0 - 120 °C and the reaction time is controlled at 0.5 - 24 h.

[0019] The basis for screening the temperature is that if the temperature is lower than 0 °C, the reaction cannot proceed or the yield is too low; if it is higher than 120 °C, crosslinking will occur.

[0020] Preferably, after the synthesis reaction is completed, it also undergoes post-treatment processes such as vacuum drying, column chromatography, recrystallization, or precipitation.

[0021] Preferably, the diameter of the obtained large spherical polysiloxane is 20 - 5000 nm.

[0022] Therefore, the present invention has the following beneficial effects: Using a fully capped double-decked polyhedral oligomeric silsesquioxane with silicon-hydrogen bonds on both sides as the raw material to synthesize large spherical polysiloxane, the yield can reach 60 - 95%, and it has the advantages of mild reaction conditions, low energy consumption, high efficiency, and simple and easy product purification process. Description of the Drawings

[0023] Figure 1 is the matrix-assisted time-of-flight mass spectrum of the large spherical polysiloxane synthesized in Example 1.

[0024] Figure 2 is the infrared spectrum of the large spherical polysiloxane synthesized in Example 1.

[0025] Figure 3 is the scanning electron microscope photograph of the large spherical polysiloxane synthesized in Example 1. Detailed Embodiments

[0026] The technical solutions of the present invention will be further specifically described below through specific examples and in conjunction with the drawings.

[0027] In the present invention, unless otherwise specified, all devices and raw materials can be purchased from the market or are commonly used in this industry. The methods in the following examples are conventional methods in this field unless otherwise specified.

[0028] Example 1

[0029] At 0 °C, a solution composed of 10 g of indium chloride and 200 mL of acetone was dropped into a 500 mL three-necked flask containing 100 g of a fully capped double-decked polyhedral oligomeric silsesquioxane with methyl and phenyl groups and silicon-hydrogen bonds on both sides and 100 mL of acetone. After stirring and reacting for 30 min, 100 g of activated carbon was added, stirred for 30 min, filtered and vacuum dried to obtain a white solid large spherical polysiloxane with a yield of 90% and a diameter of the large spherical polysiloxane of 200 - 500 nm;

[0030] The matrix-assisted time-of-flight mass spectrum of the large spherical polysiloxane synthesized from a fully capped double-decked polyhedral oligomeric silsesquioxane with methyl and phenyl groups and silicon-hydrogen bonds on both sides as the raw material is as Figure 1 shown; the infrared spectrum of the large spherical polysiloxane synthesized from a fully capped double-decked polyhedral oligomeric silsesquioxane with methyl and phenyl groups and silicon-hydrogen bonds on both sides as the raw material is as Figure 2 shown; the scanning electron microscope photograph of the large spherical polysiloxane synthesized from a fully capped double-decked polyhedral oligomeric silsesquioxane with methyl and phenyl groups and silicon-hydrogen bonds on both sides as the raw material is asFigure 3 as shown

[0031] Example 2

[0032] At a temperature of 30 °C, a solution composed of 0.01 g of tris(pentafluorophenyl)borane and 50 mL of butyl ether was added dropwise to a 100 mL three-necked flask containing 3.9 g of a fully capped double-decked polyhedral oligomeric silsesquioxane with vinyl groups on both sides and silicon-hydrogen bonds and 10 mL of butyl ether. After stirring and reacting for 3 h, 5 g of activated carbon was added, stirred for 20 min, filtered and dried under vacuum to obtain large spherical poly(silsesquioxane) as a white solid with a yield of 75% and a diameter of the large spherical poly(silsesquioxane) of 20 - 55 nm.

[0033] Example 3

[0034] At a temperature of 70 °C, a solution composed of 0.001 g of palladium chloride and 6 mL of cyclohexanone was added dropwise to a 100 mL three-necked flask containing 9 g of a fully capped double-decked polyhedral oligomeric silsesquioxane with ethyl acrylate groups on both sides and silicon-hydrogen bonds and 50 mL of cyclohexanone. After stirring and reacting for 9 h, 5 g of activated carbon was added, stirred for 30 min, filtered and dried under vacuum to obtain large spherical poly(silsesquioxane) as a white solid with a yield of 60% and a diameter of the large spherical poly(silsesquioxane) of 100 - 150 nm.

[0035] Example 4

[0036] At a temperature of 120 °C, 0.01 g of iron(III) oxide was added to a 500 mL three-necked flask containing 70 g of a fully capped double-decked polyhedral oligomeric silsesquioxane with propyl groups on both sides and silicon-hydrogen bonds and 300 mL of toluene. After stirring and reacting for 12 h, the catalyst was removed by column chromatography and dried under vacuum to obtain large spherical poly(silsesquioxane) as a white solid with a yield of 95% and a diameter of the large spherical poly(silsesquioxane) of 4500 - 5000 nm.

[0037] Example 5

[0038] At a temperature of 20 °C, 0.2 g of tin laurate was added to a 100 mL three-necked flask containing 24 g of a fully capped double-decked polyhedral oligomeric silsesquioxane with trichloromethyl groups on both sides and silicon-hydrogen bonds and 60 mL of acetone. After stirring and reacting for 24 h, the catalyst was removed by column chromatography and dried under vacuum to obtain large spherical poly(silsesquioxane) as a white solid with a yield of 75% and a diameter of the large spherical poly(silsesquioxane) of 3000 - 3300 nm.

[0039] Example 6

[0040] At a temperature of 120 °C, a solution composed of 2.5 g of ferrocene and 100 mL of 1,4-dioxane was added dropwise to a 500 mL three-necked flask containing 150 g of a fully capped double-decked polyhedral oligomeric silsesquioxane with epoxy groups on both sides and silicon-hydrogen bonds on both sides and 100 mL of 1,4-dioxane. After stirring and reacting for 30 min, 30 g of activated carbon was added, stirred for 15 min, filtered, and the reaction solution was concentrated and then poured into methanol to obtain large spherical polysiloxane as a white solid with a yield of 86%, and the diameter of the large spherical polysiloxane was 1000 - 1100 nm.

[0041] Example 7

[0042] At a temperature of 10 °C, a solution composed of 0.02 g of titanium tetrachloride and 1 mL of ethyl acetate was added to a 500 mL three-necked flask containing 120 g of a fully capped double-decked polyhedral oligomeric silsesquioxane with nitrile groups on both sides and silicon-hydrogen bonds on both sides and 300 mL of ethyl acetate. After stirring and reacting for 15 h, 5 g of activated carbon was added, stirred for 10 min, filtered and dried under vacuum to obtain large spherical polysiloxane as a white solid with a yield of 82%, and the diameter of the large spherical polysiloxane was 700 - 800 nm.

[0043] Example 8

[0044] At a temperature of 0 °C, 0.01 g of copper chloride was added to a 500 mL three-necked flask containing 100 g of a fully capped double-decked polyhedral oligomeric silsesquioxane with ethynyl groups on both sides and silicon-hydrogen bonds on both sides and 300 mL of toluene. After stirring and reacting for 20 h, 5 g of activated carbon was added, stirred for 30 min, filtered and dried under vacuum to obtain large spherical polysiloxane as a white solid with a yield of 65%, and the diameter of the large spherical polysiloxane was 300 - 350 nm.

[0045] Example 9

[0046] At a temperature of 100 °C, a solution composed of 0.01 g of chromium acetylacetonate and 1 mL of butyl ether was added to a 500 mL three-necked flask containing 40 g of a fully capped double-decked polyhedral oligomeric silsesquioxane with 2-chloroethenyl groups on both sides and silicon-hydrogen bonds on both sides and 300 mL of butyl ether. After stirring and reacting for 1 h, the catalyst was removed by column chromatography and dried under vacuum to obtain large spherical polysiloxane as a white solid with a yield of 65%, and the diameter of the large spherical polysiloxane was 200 - 300 nm.

[0047] Comparative Example 1

[0048] At a temperature of -5°C, a solution composed of 10 g of indium chloride and 200 mL of acetone was dropped into a 500 mL three-necked flask containing 100 g of a fully capped double-decked polyhedral oligomeric silsesquioxane with silicon-hydrogen bonds on both sides with methyl and phenyl groups and 100 mL of acetone. After stirring and reacting for 30 min, 100 g of activated carbon was added, stirred for 30 min, filtered and vacuum dried to obtain a white solid. The characterization data proved it to be the raw material, a fully capped double-decked polyhedral oligomeric silsesquioxane with silicon-hydrogen bonds on both sides with methyl and phenyl groups.

[0049] Comparative Example 2

[0050] At a temperature of 125°C, a solution composed of 10 g of indium chloride and 200 mL of acetone was dropped into a 500 mL three-necked flask containing 100 g of a fully capped double-decked polyhedral oligomeric silsesquioxane with silicon-hydrogen bonds on both sides with methyl and phenyl groups and 100 mL of acetone. After stirring and reacting for 30 min, a frozen substance appeared and cross-linking occurred, and large spherical polysiloxane was not obtained.

[0051] Comparative Example 3

[0052] At a temperature of 0°C, a solution composed of 0.009 g of indium chloride and 200 mL of acetone was dropped into a 500 mL three-necked flask containing 100 g of a fully capped double-decked polyhedral oligomeric silsesquioxane with silicon-hydrogen bonds on both sides with methyl and phenyl groups and 100 mL of acetone. After stirring and reacting for 30 min, 100 g of activated carbon was added, stirred for 30 min, filtered and vacuum dried to obtain a white solid. The characterization data proved it to be the raw material, a fully capped double-decked polyhedral oligomeric silsesquioxane with silicon-hydrogen bonds on both sides with methyl and phenyl groups.

[0053] Comparative Example 4

[0054] At a temperature of 0°C, a solution composed of 10.5 g of indium chloride and 200 mL of acetone was dropped into a 500 mL three-necked flask containing 100 g of a fully capped double-decked polyhedral oligomeric silsesquioxane with silicon-hydrogen bonds on both sides with methyl and phenyl groups and 100 mL of acetone. After stirring and reacting for 30 min, 100 g of activated carbon was added, stirred for 30 min, and a frozen substance appeared and cross-linking occurred, and large spherical polysiloxane was not obtained.

[0055] The performance indexes of the products of Examples 1-9 and Comparative Examples 1-4 were detected, and the results are shown in Table 1:

[0056] Table 1. Detection Results

[0057] Number Diameter (nm) Yield (%) Morphology Example 1 200～500 90 White solid Example 2 20～55 75 White solid Example 3 100～150 60 White solid Example 4 4500～5000 95 White solid Example 5 3000～3300 75 White solid Example 6 1000～1100 86 White solid Example 7 700～800 82 White solid Example 8 300～350 65 White solid Example 9 200～300 65 White solid Comparative Example 1 - - White solid of raw material Comparative Example 2 - - Insoluble and infusible white solid Comparative Example 3 - - White solid of raw material Comparative Example 4 - - Insoluble and infusible white solid

[0058] As can be seen from Table 1, the diameter of the large spherical polysiloxane obtained by the synthesis method of the present invention is 20 - 5000 nm, and the yield can reach 60 - 95%. By comparing the data of Comparative Examples 1, 2 and Example 1, it can be seen that the reaction temperature has a great influence on the product. When the temperature is lower than 0 °C, the reaction cannot proceed or the yield is too low; when it is higher than 120 °C, crosslinking will occur. By comparing the data of Comparative Examples 3, 4 and Example 1, it can be seen that the amount of catalyst has a great influence on the product. When the amount of catalyst added is too low, the reaction cannot proceed or the yield is too low; when the amount of catalyst added is too high, crosslinking will occur.

[0059] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. There are other variations and modifications without exceeding the technical solutions described in the claims.

Claims

1. A method for synthesizing large spherical polysiloxane, characterized in that, Using a fully capped double-decked polyhedral oligomeric silsesquioxane with silicon-hydrogen bonds on both sides as a raw material, reacting in an organic solvent under the action of a catalyst to obtain large spherical polysiloxane; the structural formula of the fully capped double-decked polyhedral oligomeric silsesquioxane with silicon-hydrogen bonds on both sides is as follows: Wherein, R and R’ are each independently selected from one of hydrogen, alkyl, alkenyl, alkynyl, aryl, epoxy group, ester group, sulfonic acid group, carboxyl group, nitrile group, haloalkyl, haloalkenyl, haloalkynyl; The catalyst is selected from one of the elements indium, palladium, copper, tin, titanium and chromium or the corresponding compounds; The organic solvent is selected from one of n-hexane, cyclohexane, toluene, diethyl ether, n-butyl ether, tetrahydrofuran, 1,4-dioxane, acetone, cyclohexanone, methyl isobutyl ketone, ethyl acetate; The mass ratio of the fully capped double-decked polyhedral oligomeric silsesquioxane with silicon-hydrogen bonds on both sides to the catalyst is 1:(0.0001~0.1); The reaction temperature is controlled at 0~120 °C, and the reaction time is controlled at 0.5~24 h.

2. The synthesis method of a large spherical polysiloxane according to claim 1, characterized in that, After the synthesis reaction is completed, it also undergoes post-treatment processes such as vacuum drying, column chromatography, recrystallization or precipitation.

3. A method for synthesizing a large spherical polysiloxane according to any one of claims 1-2, characterized in that, The diameter of the obtained large spherical polysiloxane is 20~5000 nm.

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