A hydroxyl-terminated silicone oil containing fluorine and boron and a method for preparing the same

Abstract

The application discloses a hydroxyl-terminated silicon oil containing fluorine and boron and a preparation method thereof, relates to the technical field of high polymer material preparation, and is prepared from dichlorosilane compounds, (3,3,3-trifluoropropyl) dichloromethylsilane and boron-containing acid through a hydrolysis-condensation method. The hydroxyl-terminated silicon oil containing fluorine and boron has a 5% weight loss temperature of 420-440 DEG C under N2 atmosphere and a glass transition temperature of -130 DEG C to -140 DEG C, and has a wide use temperature and can be applied in many extreme occasions.

Description

Technical Field

[0001] This invention relates to the field of polymer material preparation technology, and in particular to a fluorine- and boron-containing terminal hydroxyl silicone oil and its preparation method. Background Technology

[0002] Hydroxyl silicone oil is a commonly used organosilicon compound. Due to its excellent properties, such as high flexibility and ease of processing, it can be used to prepare adhesives, casting sealants, surface coatings, and composite materials, and is in urgent demand in electronics, electrical, and aerospace products. Currently, ordinary methyl silicone oil can only be used in the temperature range of -50℃ to 200℃, which is insufficient to meet the performance requirements of silicone oils in specialized fields.

[0003] Patent CN 118580496A discloses a method for preparing methylphenyl silicone oil. By introducing phenyl groups, the high steric hindrance of the phenyl groups effectively improves the high and low temperature resistance of the silicone oil, thus widening the operating temperature range of phenylmethyl silicone oil to -70℃ to 250℃. However, the introduction of phenyl groups can affect the fluidity of the silicone oil to some extent. Therefore, designing silicone oils with novel structures to further widen their operating temperature range without sacrificing fluidity is of great significance. Summary of the Invention

[0004] Based on the above, this invention provides a fluorine- and boron-containing hydroxyl-terminated silicone oil and its preparation method. The fluorine- and boron-containing hydroxyl-terminated silicone oil prepared by this invention not only greatly expands the operating temperature range of silicone oils, but also possesses certain hydrophobic properties.

[0005] This invention provides the following solution:

[0006] A fluorine- and boron-containing hydroxyl-terminated silicone oil, the silicone oil having the following structural formula:

[0007]

[0008] Among them, R1, R2 and R3 are independently methyl or phenyl;

[0009] x, y, and z all represent mole fractions; x is 0 to 0.5 and is not 0; y is 0.05 to 0.15; z is 0.02 to 0.1.

[0010] The fluorine- and boron-containing terminal hydroxyl silicone oil has x of 0.2 to 0.5, y of 0.07 to 0.13, and z of 0.02 to 0.05.

[0011] A method for preparing a fluorine- and boron-containing hydroxyl-terminated silicone oil, the method comprising the following steps:

[0012] Step 1: Hydrolyze dichlorosilane compounds to obtain Si-containing hydrolysates;

[0013] Hydrolyzing (3,3,3-trifluoropropyl)dichloromethylsilane yields an F-containing hydrolysate.

[0014] Step 2: The Si-containing hydrolysate and the F-containing hydrolysate are subjected to a polycondensation reaction with a boron-containing acid under the action of a catalyst to obtain the fluorine- and boron-containing terminal hydroxyl silicone oil.

[0015] The method for preparing the fluorine- and boron-containing hydroxyl-terminated silicone oil wherein the dichlorosilane compound is dimethyldichlorosilane, diphenyldichlorosilane, or methylphenyldichlorosilane; the boron-containing acid is methylboric acid or phenylboric acid; and the catalyst is concentrated sulfuric acid or p-toluenesulfonic acid.

[0016] The method for preparing the fluorine- and boron-containing terminal hydroxyl silicone oil, wherein the molar ratio of the dichlorosilane compound to the (3,3,3-trifluoropropyl)dichloromethylsilane and the boron-containing acid is (0-0.5):(0.05-0.15):(0.02-0.1); and the amount of the catalyst used is 1%-3% of the total molar amount of the dichlorosilane compound, (3,3,3-trifluoropropyl)dichloromethylsilane and the boron-containing acid.

[0017] The method for preparing the fluorine- and boron-containing terminal hydroxyl silicone oil involves a polycondensation reaction at a temperature of 50–80°C for 5–7 hours.

[0018] The method for preparing the fluorine- and boron-containing terminal hydroxyl silicone oil involves, in preparing the Si-containing hydrolysate, adding a dichlorosilane compound to a mixture of deionized water and organic solvent A for hydrolysis; the molar ratio of the deionized water to the dichlorosilane compound is 5-10:1; the amount of organic solvent A is 56% of the mass of the deionized water; and the organic solvent A is toluene or xylene.

[0019] The method for preparing the fluorine- and boron-containing terminal hydroxyl silicone oil involves adding (3,3,3-trifluoropropyl)dichloromethylsilane to a mixture of deionized water and organic solvent A for hydrolysis when preparing the F-containing hydrolysate; the molar ratio of deionized water to (3,3,3-trifluoropropyl)dichloromethylsilane is 5-10:1; the amount of organic solvent A is 56% of the mass of deionized water; and organic solvent A is toluene or xylene.

[0020] The method for preparing the fluorinated and boron-containing terminal hydroxyl silicone oil uses one or more solvents selected from tetrahydrofuran, N,N-dimethylformamide, toluene, 1,4-dioxane, diethylene glycol dimethyl ether, and diethylene glycol diethyl ether for the polycondensation reaction.

[0021] Technical effects of the invention:

[0022] 1. The fluorine- and boron-containing terminal hydroxyl silicone oil of the present invention has a large Si-O bond angle, resulting in high flexibility; the main chain also contains a small number of BO bonds, which have high bond energy and are not easily broken; the side chains contain a small number of CF3 bonds, whose irregularity can inhibit the low-temperature crystallization of the silicone oil to a certain extent, while also improving its hydrophobic properties. Under a N2 atmosphere, its 5% weight loss temperature is 420-440℃, and its glass transition temperature is -130--140℃, exhibiting a wide operating temperature range.

[0023] 2. This invention is the first to prepare a fluorine- and boron-containing terminal hydroxyl silicone oil via hydrolysis-condensation. Using dichlorosilane compounds, (3,3,3-trifluoropropyl)dichloromethylsilane, and boron-containing acids as raw materials, this invention synthesizes a series of fluorine- and boron-containing terminal hydroxyl silicone oils through a hydrolysis-condensation process. The method of this invention is simple and easy to industrialize and apply. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 The images show the TG and DSC secondary heating curves of the fluorine- and boron-containing terminal hydroxyl silicone oil in Example 1, illustrating that the terminal hydroxyl silicone oil containing both BO and -CF3 bonds has a higher thermal decomposition temperature and a lower glass transition temperature.

[0026] Figure 2 The infrared spectrum of the fluorine- and boron-containing terminal hydroxyl silicone oil in Example 1 is shown.

[0027] Figure 3 The NMR boron spectrum of the fluorine- and boron-containing terminal hydroxyl silicone oil in Example 1 is shown.

[0028] Figure 4 This is a comparison diagram of the water contact angles between the fluorine- and boron-containing terminal hydroxyl silicone oil in Example 1 and the reference sample. Detailed Implementation

[0029] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0030] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0031] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0032] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0033] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0034] The first aspect of this invention provides a fluorine- and boron-containing terminal hydroxyl silicone oil, with the following structural formula:

[0035]

[0036] Among them, R1, R2 and R3 are independently methyl or phenyl;

[0037] x, y, and z all represent mole fractions; x is 0 to 0.5 and is not 0; y is 0.05 to 0.15; z is 0.02 to 0.1.

[0038] In a preferred embodiment of the present invention, x is 0.2 to 0.5; y is 0.07 to 0.13; and z is 0.02 to 0.05.

[0039] In a more preferred embodiment of the present invention, x is 0.2 to 0.35.

[0040] The fluorine- and boron-containing terminal hydroxyl silicone oil prepared by this invention exhibits a wide operating temperature range. Because the bond energy of the BO bond (537.6 KJ / mol) is much greater than that of the Si-O bond (460.5 KJ / mol), the thermal stability of the silicone oil backbone is significantly improved. Under a N2 atmosphere, its 5% weight loss occurs at 420–440 °C. Simultaneously, the introduction of -CH2CH2CF3 into the side chain disrupts the regularity of the silicone oil chain segments and increases the difficulty of molecular chain movement, thereby effectively inhibiting the crystallization of the silicone oil at low temperatures. Its glass transition temperature is -130–-140 °C. Furthermore, the F atoms on the side chain contribute to the low surface energy of the silicone oil, giving it excellent hydrophobic properties. In summary, the fluorine- and boron-containing terminal hydroxyl silicone oil prepared by this invention not only possesses a wide operating temperature range but also exhibits certain hydrophobicity, making it suitable for applications in many extreme environments, such as fields requiring high-temperature resistance, low-temperature resistance, and hydrophobic properties.

[0041] A second aspect of the present invention provides a method for preparing the fluorine- and boron-containing terminal hydroxyl silicone oil, comprising the following steps:

[0042] Step 1: Hydrolyze dichlorosilane compounds to obtain Si-containing hydrolysates;

[0043] Hydrolyzing (3,3,3-trifluoropropyl)dichloromethylsilane yields an F-containing hydrolysate.

[0044] Step 2: The Si-containing hydrolysate and the F-containing hydrolysate are subjected to a polycondensation reaction with a boron-containing acid under the action of a catalyst to obtain the fluorine- and boron-containing terminal hydroxyl silicone oil. (That is, a terminal hydroxyl silicone oil with a main chain containing BO bonds and a side chain containing -CF3)

[0045] In a preferred embodiment of the present invention, the dichlorosilane compound is dimethyldichlorosilane, diphenyldichlorosilane, or methylphenyldichlorosilane; the boron-containing acid is methylboric acid or phenylboric acid; and the catalyst is concentrated sulfuric acid or p-toluenesulfonic acid.

[0046] In a preferred embodiment of the present invention, the molar ratio of the dichlorosilane compound to the (3,3,3-trifluoropropyl)dichloromethylsilane and the boron-containing acid is (0-0.5):(0.05-0.15):(0.02-0.1); the amount of the catalyst is 1%-3% of the total molar amount of the dichlorosilane compound, (3,3,3-trifluoropropyl)dichloromethylsilane and the boron-containing acid.

[0047] In a preferred embodiment of the present invention, the polycondensation reaction is carried out at a temperature of 50–80°C for 5–7 hours.

[0048] In a preferred embodiment of the present invention, when preparing the Si-containing hydrolysate, a dichlorosilane compound is added to a mixture of deionized water and organic solvent A for hydrolysis; the molar ratio of the deionized water to the dichlorosilane compound is 5 to 10:1; the amount of organic solvent A is 56% of the mass of the deionized water; and the organic solvent A is toluene or xylene.

[0049] In a preferred embodiment of the present invention, when preparing the F-containing hydrolysate, (3,3,3-trifluoropropyl)dichloromethylsilane is added to a mixture of deionized water and organic solvent A for hydrolysis; the molar ratio of deionized water to (3,3,3-trifluoropropyl)dichloromethylsilane is 5 to 10:1; the amount of organic solvent A is 56% of the mass of deionized water; and the organic solvent A is toluene or xylene.

[0050] In preparing the Si-containing and F-containing hydrolysates, hydrolysis was performed in two stages. After the initial hydrolysis reaction reached a certain time, the acidic water was removed, and the same amount of deionized water was added for a second hydrolysis. After the same time, the acidic water was removed again to obtain the corresponding hydrolysates. The hydrolysis of both the Si-containing and F-containing hydrolysates was carried out in an ice-water bath or at room temperature; the hydrolysis time was 20–60 minutes.

[0051] In a preferred embodiment of the present invention, the solvent used in the polycondensation reaction is one or more selected from tetrahydrofuran, N,N-dimethylformamide, toluene, 1,4-dioxane, diethylene glycol dimethyl ether, and diethylene glycol diethyl ether. Specifically, when the boron-containing acid is methylboric acid, the solvent used in the polycondensation reaction is tetrahydrofuran or N,N-dimethylformamide; when the boron-containing acid is phenylboronic acid, the solvent used in the polycondensation reaction is one or more selected from toluene, 1,4-dioxane, diethylene glycol dimethyl ether, and diethylene glycol diethyl ether.

[0052] After the polycondensation reaction is completed, the process also includes the steps of allowing the product to stand and separate into layers, removing acid water and then evaporating the solvent, washing the resulting product and then drying it.

[0053] The molar volume ratio of the solvent to the boron-containing acid used in the polycondensation reaction is (0.07–0.1) mol: (25–30) mL.

[0054] A third aspect of the present invention provides the application of the fluorine- and boron-containing terminal hydroxyl silicone oil in the preparation of electronic, electrical, or aerospace products.

[0055] In practical applications, the fluorine- and boron-containing terminal hydroxyl silicone oil of the present invention can be further cured into silicone rubber, making it an elastomer material that not only has a wide operating temperature range but also excellent hydrophobicity.

[0056] Unless otherwise specified, the technical solutions described in this invention are all conventional solutions in the field, and the reagents or raw materials used are all purchased from commercial channels or are publicly available unless otherwise specified.

[0057] The testing and analysis methods involved in this invention are as follows:

[0058] Boron NMR spectroscopy: The test was performed using deuterated chloroform as a solvent and a pure quartz NMR tube.

[0059] TG test (a standard test method in this field): Under a nitrogen atmosphere, with an initial equilibrium temperature of 30°C, the temperature is increased to 800°C at a rate of 10°C / min, and the T5 value of the resulting fluorine-containing and boron-terminated hydroxyl silicone oil is read.

[0060] DSC test (a standard test method in this field): Under a nitrogen atmosphere, the initial equilibrium temperature is 30°C, then the temperature is decreased to -170°C at a rate of 10°C / min and held for 5 min; subsequently, the sample is heated from -170°C to 30°C at a rate of 10°C / min. The T value of the resulting fluorinated and boron-terminated hydroxyl silicone oil is read from the second heating curve. g value.

[0061] Water contact angle test (a standard test method in this field): The θ value of H2O and the sample was measured using an MC500 angle contact tester, and the average value was obtained after five measurements. The water droplet used in the water contact angle test was 4 μL.

[0062] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0063] Example 1

[0064] A method for preparing a fluorine- and boron-containing hydroxyl-terminated silicone oil, comprising the following steps:

[0065] (1) Hydrolysis of dimethyldichlorosilane

[0066] Add 52.20 g of deionized water and 29.23 g of toluene to a three-necked flask. Under mechanical stirring at 30 °C, add a certain amount of dimethyldichlorosilane (37.43 g) dropwise to the three-necked flask over 15 min. Continue stirring under the same conditions for 30 min, then separate the lower acidic water layer. Add the same amount of deionized water to hydrolyze for 30 min, then separate the acidic water to obtain the Si-containing hydrolysate.

[0067] (2) Hydrolysis of (3,3,3-trifluoropropyl)dichloromethylsilane

[0068] Add deionized water (3.60 g) and toluene (2.01 g) to a three-necked flask. Under mechanical stirring at 30 °C, add a certain amount of (3,3,3-trifluoropropyl)dichloromethylsilane (4.49 g) dropwise to the three-necked flask over 15 min. Continue stirring under the same conditions for 30 min, then separate the lower acidic water layer. Add the same amount of deionized water to hydrolyze for 30 min, then separate the acidic water to obtain the F-containing hydrolysate.

[0069] (3) Condensation of Si-containing hydrolysate, F-containing hydrolysate and methylboronic acid

[0070] Methylboric acid (4.19 g) was dissolved in 25 mL of tetrahydrofuran and added to the Si-containing hydrolysate and the F-containing hydrolysate. The mixture was stirred thoroughly for 10 min, then 1.08 g of p-toluenesulfonic acid was added as a catalyst, and the mixture was heated to 50 °C and reacted for 8 h. After the reaction was complete, the mixture was allowed to stand and separate into layers. The acidic water was removed, and the solvent was evaporated. The product was then washed three times with deionized water and anhydrous ethanol (using twice the volume of the product). Finally, it was dried under vacuum at 90 °C for 24 h to obtain a fluorinated and boron-terminated hydroxyl-terminated silicone oil.

[0071] The structure of the fluorine- and boron-containing terminal hydroxyl silicone oil prepared in this embodiment is as follows:

[0072]

[0073] Where: x = 0.29, y = 0.07, z = 0.02.

[0074] Figure 1 The figures show the TG and DSC secondary heating curves of the fluorine- and boron-containing terminal hydroxyl silicone oil in Example 1; this indicates that the terminal hydroxyl silicone oil containing both BO and -CF3 bonds has a higher thermal decomposition temperature and a lower glass transition temperature. Furthermore, water contact angle testing shows that this hydroxyl silicone oil possesses good hydrophobicity (e.g., ...). Figure 4 As shown, Figure 4 "methylsilicone oil" refers to hydroxyl-terminated silicone oil, "B methylsilicone oil" refers to boron-containing hydroxyl-terminated silicone oil, and "BF methylsilicone oil (Instance 1)" refers to the fluorine- and boron-containing hydroxyl-terminated silicone oil prepared in Example 1.

[0075] Infrared and hydrogen NMR spectra were used to further verify the consistency between the synthesized product and the expected outcome. For example, for the fluorine- and boron-containing terminal hydroxyl silicone oil prepared in Example 1, the infrared spectrum ( Figure 2 In ), 3701cm -1 The absorption peak at 1370 cm⁻¹ is for -OH; -1 and 1210cm -1The absorption peaks observed at the positions are the stretching vibration absorption peak of -CH2- in -CH2CH2CF3 and the stretching vibration absorption peak of CF, respectively, confirming that element F has been successfully introduced into the side chain of silicone oil. However, the absorption peak of BO bond (1410) coincides with the bending vibration peak of Si-C bond (1407), so whether the B atom has been successfully introduced into the main chain of silicone oil still needs further investigation. 11 B-NMR characterization was used to confirm this. Further analysis was conducted using... 11 B NMR spectrum ( Figure 3 It can be observed that the broad peak at δ3.84ppm is the absorption peak of B, confirming that the BO bond has been successfully introduced into the main chain of the silicone oil. Therefore, the above characterization results confirm that the terminal hydroxyl silicone oil containing both fluorine and boron has been successfully prepared.

[0076] Example 2

[0077] A method for preparing a fluorine- and boron-containing hydroxyl-terminated silicone oil, comprising the following steps:

[0078] (1) Hydrolysis of dimethyldichlorosilane

[0079] Add deionized water (46.80 g) and toluene (26.21 g) to a three-necked flask. Under mechanical stirring at 30 °C, add a certain amount of dimethyldichlorosilane (33.56 g) dropwise to the three-necked flask within 15 min. Continue stirring under the same conditions for 30 min, and then separate the lower acidic water layer. Add the same amount of deionized water to hydrolyze for 30 min, and then separate the acidic water to obtain the Si-containing hydrolysate.

[0080] (2) Hydrolysis of (3,3,3-trifluoropropyl)dichloromethylsilane

[0081] Add 5.40 g of deionized water and 3.02 g of toluene to a three-necked flask. Under mechanical stirring at 30 °C, add a certain amount of (3,3,3-trifluoropropyl)dichloromethylsilane (6.33 g) dropwise to the three-necked flask over 15 min. Continue stirring under the same conditions for 30 min, then separate the lower acidic water layer. Add the same amount of deionized water to hydrolyze for 30 min, then separate the acidic water to obtain the F-containing hydrolysate.

[0082] (3) Condensation of Si-containing hydrolysate, F-containing hydrolysate and methylboronic acid

[0083] Methylboric acid (5.39 g) was dissolved in 25 mL of tetrahydrofuran and added to the Si-containing and F-containing hydrolysates. After stirring thoroughly for 10 min, 1.08 g of p-toluenesulfonic acid was added as a catalyst, and the mixture was heated to 50 °C and reacted for 8 h. After the reaction was complete, the mixture was allowed to stand and separate into layers. The acidic water was removed, and the solvent was evaporated. The mixture was then washed three times with deionized water and anhydrous ethanol (twice the volume of the product). Finally, it was dried under vacuum at 90 °C for 24 h to obtain a fluorinated and boron-terminated hydroxyl-terminated silicone oil.

[0084] The structure of the fluorine- and boron-containing terminal hydroxyl silicone oil prepared in this embodiment is as follows:

[0085]

[0086] Where: x = 0.26, y = 0.09, z = 0.03.

[0087] The fluorine- and boron-containing terminal hydroxyl silicone oil prepared in this embodiment has a 5% weight loss temperature of 423°C and a glass transition temperature of -132°C.

[0088] Example 3

[0089] A method for preparing a fluorine- and boron-containing hydroxyl-terminated silicone oil, comprising the following steps:

[0090] (1) Hydrolysis of dimethyldichlorosilane

[0091] Add deionized water (41.40 g) and toluene (23.18 g) to a three-necked flask. Under mechanical stirring at 30 °C, add a certain amount of dimethyldichlorosilane (29.68 g) dropwise to the three-necked flask within 15 min. Continue stirring under the same conditions for 30 min, and then separate the lower acidic water layer. Add the same amount of deionized water to hydrolyze for 30 min, and then separate the acidic water to obtain the Si-containing hydrolysate.

[0092] (2) Hydrolysis of (3,3,3-trifluoropropyl)dichloromethylsilane

[0093] Add deionized water (7.20 g) and toluene (4.03 g) to a three-necked flask. Under mechanical stirring at 30 °C, add a certain amount of (3,3,3-trifluoropropyl)dichloromethylsilane (8.44 g) dropwise to the three-necked flask within 15 min. Continue stirring under the same conditions for 30 min, and then separate the lower acidic water layer. Add the same amount of deionized water to hydrolyze for 30 min, and then separate the acidic water to obtain the F-containing hydrolysate.

[0094] (3) Condensation of Si-containing hydrolysate, F-containing hydrolysate and methylboronic acid

[0095] Methylboric acid (6.58 g) was dissolved in 25 mL of tetrahydrofuran and added to the Si-containing and F-containing hydrolysates. The mixture was stirred thoroughly for 10 min, then 1.08 g of p-toluenesulfonic acid was added as a catalyst, and the reaction was carried out at 50 °C for 8 h. After the reaction was complete, the mixture was allowed to stand and separate into layers. The acidic water was removed, and the solvent was evaporated. The product was then washed three times with deionized water and anhydrous ethanol (twice the volume of the product). Finally, it was dried under vacuum at 90 °C for 24 h to obtain a fluorinated and boron-terminated hydroxyl-terminated silicone oil.

[0096] The structure of the fluorine- and boron-containing terminal hydroxyl silicone oil prepared in this embodiment is as follows:

[0097]

[0098] Where: x = 0.23, y = 0.11, z = 0.04.

[0099] The fluorine- and boron-containing terminal hydroxyl silicone oil prepared in this embodiment has a 5% weight loss temperature of 426°C and a glass transition temperature of -133°C.

[0100] Example 4

[0101] A method for preparing a fluorine- and boron-containing hydroxyl-terminated silicone oil, comprising the following steps:

[0102] (1) Hydrolysis of dimethyldichlorosilane

[0103] Add 52.38 g of deionized water and 29.33 g of toluene to a three-necked flask and stir mechanically under ice bath conditions. Add a certain amount of dimethyldichlorosilane (37.56 g) dropwise to the three-necked flask within 15 min and continue stirring under the same conditions for 30 min. Separate the lower acidic water layer. Add the same amount of deionized water to hydrolyze for 30 min and separate the acidic water to obtain the Si-containing hydrolysate.

[0104] (2) Hydrolysis of (3,3,3-trifluoropropyl)dichloromethylsilane

[0105] Add 11.24 g of deionized water and 6.29 g of toluene to a three-necked flask and stir mechanically in an ice bath. Within 15 min, add a certain amount of (3,3,3-trifluoropropyl)dichloromethylsilane (4.49 g) dropwise to the three-necked flask and continue stirring under the same conditions for 30 min. Then separate the lower acidic water layer. Add the same amount of deionized water to hydrolyze for 30 min and separate the acidic water to obtain the F-containing hydrolysate.

[0106] (3) Condensation of Si-containing hydrolysates, F-containing hydrolysates, and phenylboronic acid

[0107] 8.54 g of phenylboronic acid was dissolved in 25 mL of 1,4-dioxane and added to the Si-containing and F-containing hydrolysates. The mixture was stirred thoroughly for 10 min, then 0.56 g of concentrated sulfuric acid was added as a catalyst, and the reaction was carried out at 50 °C for 8 h. After the reaction was complete, the mixture was allowed to stand and separate into layers. The acid and water were removed, and the solvent was evaporated. The product was then washed three times with deionized water and anhydrous ethanol (twice the volume of the product). Finally, it was dried under vacuum at 90 °C for 24 h to obtain a fluorinated and boron-terminated hydroxyl-terminated silicone oil.

[0108] The structure of the fluorine- and boron-containing terminal hydroxyl silicone oil prepared in this embodiment is as follows:

[0109]

[0110] Where: x = 0.29, y = 0.07, z = 0.02.

[0111] The fluorine- and boron-containing terminal hydroxyl silicone oil prepared in this embodiment has a 5% weight loss temperature of 427°C and a glass transition temperature of -135°C.

[0112] Example 5

[0113] A method for preparing a fluorine- and boron-containing hydroxyl-terminated silicone oil, comprising the following steps:

[0114] (1) Hydrolysis of diphenyldichlorosilane

[0115] Add 52.38 g of deionized water and 29.33 g of toluene to a three-necked flask and stir mechanically under ice bath conditions. Add a certain amount of diphenyldichlorosilane (73.68 g) dropwise to the three-necked flask within 15 min and continue stirring under the same conditions for 30 min. Separate the lower acidic water layer. Add the same amount of deionized water to hydrolyze for 30 min and separate the acidic water to obtain the Si-containing hydrolysate.

[0116] (2) Hydrolysis of (3,3,3-trifluoropropyl)dichloromethylsilane

[0117] Add 11.24 g of deionized water and 6.29 g of toluene to a three-necked flask and stir mechanically in an ice bath. Within 15 min, add a certain amount of (3,3,3-trifluoropropyl)dichloromethylsilane (4.49 g) dropwise to the three-necked flask and continue stirring under the same conditions for 30 min. Then separate the lower acidic water layer. Add the same amount of deionized water to hydrolyze for 30 min and separate the acidic water to obtain the F-containing hydrolysate.

[0118] (3) Condensation of Si-containing hydrolysates, F-containing hydrolysates, and phenylboronic acid

[0119] 8.54 g of phenylboronic acid was dissolved in 25 mL of diethylene glycol dimethyl ether and added to the Si-containing and F-containing hydrolysates. After stirring thoroughly for 10 min, 1.08 g of p-toluenesulfonic acid was added as a catalyst, and the mixture was heated to 50 °C and reacted for 8 h. After the reaction was complete, the mixture was allowed to stand and separate into layers. The acidic water was removed, and the solvent was evaporated. The mixture was then washed three times with deionized water and anhydrous ethanol (twice the volume of the product). Finally, it was dried under vacuum at 90 °C for 24 h to obtain a fluorinated and boron-terminated hydroxyl-terminated silicone oil.

[0120] The structure of the prepared fluorine- and boron-containing terminal hydroxyl silicone oil is as follows:

[0121]

[0122] Where: x = 0.29, y = 0.07, z = 0.02.

[0123] The fluorine- and boron-containing terminal hydroxyl silicone oil prepared in this embodiment has a 5% weight loss temperature of 440°C and a glass transition temperature of -139°C.

[0124] Example 6

[0125] A method for preparing a fluorine- and boron-containing hydroxyl-terminated silicone oil, comprising the following steps:

[0126] (1) Hydrolysis of diphenyldichlorosilane

[0127] Add 52.38 g of deionized water and 29.33 g of toluene to a three-necked flask and stir mechanically under ice bath conditions. Add a certain amount of diphenyldichlorosilane (73.68 g) dropwise to the three-necked flask within 15 min and continue stirring under the same conditions for 30 min. Separate the lower acidic water layer. Add the same amount of deionized water to hydrolyze for 30 min and separate the acidic water to obtain the Si-containing hydrolysate.

[0128] (2) Hydrolysis of (3,3,3-trifluoropropyl)dichloromethylsilane

[0129] Add 11.24 g of deionized water and 6.29 g of toluene to a three-necked flask and stir mechanically in an ice bath. Within 15 min, add a certain amount of (3,3,3-trifluoropropyl)dichloromethylsilane (4.49 g) dropwise to the three-necked flask and continue stirring under the same conditions for 30 min. Then separate the lower acidic water layer. Add the same amount of deionized water to hydrolyze for 30 min and separate the acidic water to obtain the F-containing hydrolysate.

[0130] (3) Condensation of Si-containing hydrolysate, F-containing hydrolysate and methylboronic acid

[0131] Methylboric acid (8.54 g) was dissolved in 25 mL of N,N-dimethylformamide and added to the Si-containing hydrolysate and the F-containing hydrolysate. After stirring thoroughly for 10 min, 1.08 g of p-toluenesulfonic acid was added as a catalyst, and the mixture was heated to 50 °C and reacted for 8 h. After the reaction was complete, the mixture was allowed to stand and separate into layers. The acidic water was removed, and the solvent was evaporated. The mixture was then washed three times with deionized water and anhydrous ethanol (twice the volume of the product). Finally, it was dried under vacuum at 90 °C for 24 h to obtain a fluorinated and boron-terminated hydroxyl-terminated silicone oil.

[0132] The structure of the prepared fluorine- and boron-containing terminal hydroxyl silicone oil is as follows:

[0133]

[0134] Where: x = 0.29, y = 0.07, z = 0.02.

[0135] The fluorine- and boron-containing terminal hydroxyl silicone oil prepared in this embodiment has a 5% weight loss temperature of 434°C and a glass transition temperature of -137°C.

[0136] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A process for the preparation of a hydroxy-terminated silicone oil containing fluorine and boron, characterized in that, The method comprises the following steps: Step 1, hydrolyzing dichlorosilane compounds to obtain Si-containing hydrolysate; hydrolyzing (3,3,3-trifluoropropyl) dichloromethylsilane to obtain F-containing hydrolysate; Step 2, polycondensation reaction of the Si-containing hydrolysate and the F-containing hydrolysate with boron-containing acid under the action of a catalyst to obtain the fluorine and boron-containing hydroxyl-terminated silicone oil; The silicone oil has the following structural formula: ; wherein R1, R2 and R3 are independently methyl or phenyl; x, y and z each represent a mole fraction; x is 0-0.5 and not 0; y is 0.05-0.15; z is 0.02-0.1; The dichlorosilane compound is dimethyldichlorosilane, diphenyldichlorosilane or methylphenyldichlorosilane; the boron-containing acid is methylboric acid or phenylboric acid; and the catalyst is concentrated sulfuric acid or p-toluenesulfonic acid. The molar ratio of the dichlorosilane compound to the (3,3,3-trifluoropropyl) dichloromethylsilane and the boron-containing acid is (0-0.5):(0.05-0.15):(0.02-0.1); and the amount of the catalyst is 1%-3% of the total moles of the dichlorosilane compound, (3,3,3-trifluoropropyl) dichloromethylsilane and boron-containing acid.

2. The method for producing a fluorine- and boron-containing hydroxy-terminated silicone oil according to claim 1, characterized by, The temperature of the polycondensation reaction is 50-80 ℃, and the time is 5-7 h.

3. The method for preparing fluorine- and boron-containing terminal hydroxyl silicone oil according to claim 1, characterized in that, In preparing the Si-containing hydrolysate, the dichlorosilane compound is added to a mixture of deionized water and an organic solvent A for hydrolysis; the molar ratio of the deionized water to the dichlorosilane compound is 5-10:1; the amount of the organic solvent A is 56% of the mass of the deionized water; and the organic solvent A is toluene or xylene.

4. The method for preparing fluorine- and boron-containing terminal hydroxyl silicone oil according to claim 1, characterized in that, In preparing the F-containing hydrolysate, (3,3,3-trifluoropropyl) dichloromethylsilane is added to a mixture of deionized water and an organic solvent A for hydrolysis; the molar ratio of the deionized water to the (3,3,3-trifluoropropyl) dichloromethylsilane is 5-10:1; the amount of the organic solvent A is 56% of the mass of the deionized water; and the organic solvent A is toluene or xylene.

5. The method for preparing fluorine- and boron-containing terminal hydroxyl silicone oil according to claim 1, characterized in that, The solvent used in the polycondensation reaction is one or more of tetrahydrofuran, N,N-dimethylformamide, toluene, 1,4-dioxane, diethylene glycol dimethyl ether and diethylene glycol diethyl ether.

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