Preparation method of polyether modified silicone oil
Through the cross-linking reaction catalyzed by ionic liquid catalyst and chloroplatinic acid, the problem of excessive use of solvents and catalysts in the preparation of traditional polyether modified silicone oil is solved, which improves the thermal stability and environmental protection of the product, and produces more stable and robust Modified polymer.
Patent Information
- Application Number
- CN202411500191.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-25
- Publication Date
- 2024-12-10
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
Traditional polyether modified silicone oil requires the use of solvents and a large number of catalysts during the synthesis and preparation process, and the finished product contains more impurities, resulting in high preparation cost and unfavorable for environmental protection.
Ionic liquid catalyst is used to remove moisture and impurities from hydrogen-containing silicone oil, and unsaturated polyether is formed by reaction of propylene oxide and propylene glycol, and crosslinking with low hydrogen-containing silicone oil under chloroplatinic acid catalyzed to reduce catalyst content and impurity residues. .
It improves the thermal stability and cross-linking reaction efficiency of polyether modified silicone oil, reduces the amount of catalyst used, and generates more stable and robust modified polymers, which have higher environmental protection.
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Figure CN119101248A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of chemistry and chemical engineering, and specifically relates to a method for preparing polyether modified silicone oil. Background Art
[0002] Silicone oil is an organic silicon compound mainly composed of silicon-oxygen chains, which usually has good thermal stability, chemical inertness and excellent lubricity. It is widely used in cosmetics, lubricants, electronic materials, building materials and other fields.
[0003] Polyether-modified silicone oil refers to a class of organic silicon compounds that introduce polyether segments into silicone oil molecules to increase their hydrophilicity or improve their compatibility. Polyether-modified silicone oil combines the excellent properties of silicone oil with the hydrophilicity of polyether, and is therefore widely used in coatings, agriculture, personal care products and other fields.
[0004] However, traditional polyether-modified silicone oils require the use of solvents to participate in the reaction during the synthesis and preparation process, and a large amount of catalyst is added when polyether reacts with hydrogen-containing silicone oil, resulting in high preparation costs and being environmentally unfriendly. The finished polyether-modified silicone oils prepared by synthesis contain a large amount of impurities, which is not conducive to use. Summary of the invention
[0005] The object of the present invention is to provide a method for preparing polyether-modified silicone oil to solve the problems raised in the above background technology.
[0006] To achieve the above object, the present invention provides the following technical solutions:
[0007] A method for preparing polyether modified silicone oil comprises the following steps:
[0008] S1, adding hydrogen-containing silicone oil and ionic liquid catalyst into a reactor for heating reaction to obtain low hydrogen-containing silicone oil;
[0009] S2, mixing propylene oxide and propylene glycol, adding them together with sodium hydroxide into a reactor for heating reaction, adding acrylic acid after the reaction is completed and reacting to obtain an unsaturated polyether;
[0010] S3, adding the obtained low hydrogen silicone oil and unsaturated polyether into a three-necked flask, and adding chloroplatinic acid catalyst to carry out heating reaction;
[0011] S4. After the reaction is completed, the temperature is cooled to obtain polyether modified silicone oil.
[0012] Preferably, in step S3, the molar ratio of the low hydrogen silicone oil to the unsaturated polyether is 1:0.5 to 1:1.5, and the proportion of the chloroplatinic acid catalyst is 0.1% to 0.5%.
[0013] Preferably, in step S1, the weight ratio of the hydrogen-containing silicone oil to the ionic liquid catalyst is 1:0.05 to 1:0.1, ensuring that the concentration of the ionic liquid is moderate.
[0014] Preferably, in step S1, the heating temperature of the reactor is 80 to 120 degrees Celsius, the reaction time is 3 to 5 hours, and uniform stirring is maintained during the reaction.
[0015] Preferably, in step S2, propylene oxide and propylene glycol are mixed in a molar ratio of 1:1, and the proportion of sodium hydroxide is 0.1% to 1%.
[0016] Preferably, in the step S2, the heating temperature of the reactor is 80 to 120 degrees Celsius, the pressure is maintained at 0.4 to 0.6 MPa, the reaction time is 4 to 6 hours, uniform stirring is maintained during the reaction, and the reaction is continued for 1 to 2 hours after adding acrylic acid to the reactor, and the proportion of acrylic acid is 5% to 15%.
[0017] Preferably, after the reaction in step S2 is completed, the pressure of the reactor is reduced to 0.15-0.2 MPa, the temperature in the reactor is lowered and then emptied, the reactor is connected to a vacuum pump and evacuated, the temperature in the reactor is maintained at 65-75 degrees Celsius, and nitrogen, helium or argon is introduced to remove small molecules, the reaction product is taken out and naturally cooled, filtered with acidic clay, activated carbon or silica gel to remove solid impurities and catalyst residues, and the molecular weight and structure of the polyether are sampled and analyzed.
[0018] Preferably, in the step S3, the heating temperature of the three-necked flask is 100 to 120 degrees Celsius, the reaction time is 4 to 8 hours, constant stirring is maintained during the reaction, and the temperature and pressure are monitored in real time.
[0019] Preferably, in step S4, after the reaction is completed and cooled, the reactants are filtered using activated carbon or silica gel to remove solid impurities and catalyst residues.
[0020] Preferably, in the steps S1, S2 and S3, before carrying out the reaction work, the reaction kettle and the three-necked flask are dried and cleaned to ensure that no impurities remain.
[0021] Compared with the prior art, the present invention has the following beneficial effects:
[0022] The present invention can effectively remove moisture and other organic impurities in hydrogen-containing silicone oil through an ionic liquid catalyst, reduce the hydrogen content in the hydrogen-containing silicone oil, and has better thermal stability. Propylene oxide and propylene glycol are mixed and added into a reactor together with sodium hydroxide for heating reaction. Acrylic acid added after the reaction is completed is used to introduce unsaturated groups to increase the reactivity and cross-linking ability of polyether. Finally, the low-hydrogen-containing silicone oil and chloroplatinic acid catalyst are added into a three-necked flask for reaction to generate polyether-modified silicone oil. Since the two macromolecular intermediates of the low-hydrogen-containing silicone oil and the unsaturated polyether have small molecular weights and high activity, the content of the chloroplatinic acid catalyst can be greatly reduced. Since the low-hydrogen-containing silicone oil has a lower hydrogen group content, the low-hydrogen-containing silicone oil can more efficiently undergo a cross-linking reaction with the unsaturated polyether, thereby generating a more stable and firm modified polymer, and more environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:
[0024] Figure 1 The figure is a flowchart of the method steps of the present invention. DETAILED DESCRIPTION
[0025] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.
[0026] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.
[0027] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.
[0028] As attached Figure 1 As shown:
[0029] Embodiment 1: This embodiment provides a method for preparing polyether-modified silicone oil, comprising the following steps:
[0030] S1, adding hydrogen-containing silicone oil and ionic liquid catalyst into a reactor for heating reaction to obtain low hydrogen-containing silicone oil;
[0031] S2, mixing propylene oxide and propylene glycol, adding them together with sodium hydroxide into a reactor for heating reaction, adding acrylic acid after the reaction is completed and reacting to obtain an unsaturated polyether;
[0032] S3, adding the obtained low hydrogen silicone oil and unsaturated polyether into a three-necked flask, and adding chloroplatinic acid catalyst to carry out heating reaction;
[0033] S4. After the reaction is completed, the temperature is cooled to obtain polyether modified silicone oil.
[0034] By adding hydrogen-containing silicone oil and ionic liquid catalyst into a reactor for heating reaction, such as 1-butyl-3-methylimidazolium chloride, as a green catalyst, it has excellent solubility and catalytic activity, and can effectively remove moisture and other organic impurities in low-hydrogen silicone oil. The interaction between its cations and anions can break the combination of impurity molecules and the main reactants, thereby removing impurities in hydrogen-containing silicone oil and reducing the hydrogen content in hydrogen-containing silicone oil to generate low-hydrogen silicone oil with better thermal stability and reduced degradation risk in high-temperature applications;
[0035] Propylene oxide and propylene glycol are mixed, and added into a reactor together with sodium hydroxide for heating reaction. Propylene oxide is the main reactant of the polyetherification reaction. Propylene glycol provides alcohol groups, and its hydroxyl groups can form polymers with propylene oxide, improve the solubility and dispersibility of the polymer, and directly affect the molecular weight and viscosity of the product. The ring-opening reaction of propylene oxide is catalyzed by sodium hydroxide to increase the reaction rate, making the polyetherification reaction more efficient, so that propylene oxide reacts with propylene glycol through the ring-opening reaction to form polyether, and the oxygen atoms in its ring structure are opened under the action of sodium hydroxide to form a compound. The acrylic acid added after the reaction is completed is used to introduce unsaturated groups, increase the reactivity and cross-linking ability of the polyether, and enhance its physical and chemical stability. The reaction is continued to introduce a carbon-carbon unsaturated double bond at one end of the polyether, and its double bond structure can participate in cross-linking in subsequent reactions;
[0036] Finally, add them together with low-hydrogen silicone oil and chloroplatinic acid catalyst into a three-necked flask for reaction. During the reaction, the unsaturated bonds of the polyether can react with the silicon-hydrogen groups in the low-hydrogen silicone oil to form new covalent bonds. The chloroplatinic acid catalyst forms an active intermediate to provide the required activation energy, which helps to promote the addition reaction of silicon-hydrogen groups with unsaturated polyethers and increase the reaction rate, ultimately generating polyether-modified silicone oil. Since the two macromolecular intermediates, low-hydrogen silicone oil and unsaturated polyether, have small molecular weights and high activity, the content of chloroplatinic acid catalyst can be greatly reduced. Since low-hydrogen silicone oil contains a lower hydrogen content, it can more efficiently undergo cross-linking reaction with unsaturated polyethers, thereby producing a more stable and strong modified polymer, which does not even require the participation of chloroplatinic acid catalysts and is more environmentally friendly.
[0037] Specifically, in step S3, the molar ratio of the low hydrogen silicone oil to the unsaturated polyether is 1:0.5, and the proportion of the chloroplatinic acid catalyst is 0.1% to 0.5%.
[0038] Specifically, in step S1, the weight ratio of the hydrogen-containing silicone oil to the ionic liquid catalyst is 1:0.05 to 1:0.1, ensuring that the concentration of the ionic liquid is moderate.
[0039] Specifically, in step S1, the heating temperature of the reactor is 80 to 120 degrees Celsius, the reaction time is 3 to 5 hours, and uniform stirring is maintained during the reaction.
[0040] Specifically, in step S2, propylene oxide and propylene glycol are mixed in a molar ratio of 1:1, and the proportion of sodium hydroxide is 0.1% to 1%.
[0041] Specifically, in the step S2, the heating temperature of the reactor is 80 to 120 degrees Celsius, the pressure is maintained at 0.4 to 0.6 MPa, the reaction time is 4 to 6 hours, and uniform stirring is maintained during the reaction. After adding acrylic acid to the reactor, the reaction is continued for 1 to 2 hours, and the proportion of acrylic acid is 5% to 15%.
[0042] Specifically, after the reaction in step S2 is completed, the pressure of the reactor is reduced to 0.15-0.2 MPa, the temperature in the reactor is lowered and then emptied, the reactor is connected to a vacuum pump and evacuated, the temperature in the reactor is maintained at 65-75 degrees Celsius, and nitrogen, helium or argon is introduced to remove small molecules, the reaction product is taken out and naturally cooled, filtered with acidic clay, activated carbon or silica gel to remove solid impurities and catalyst residues, and the molecular weight and structure of the polyether are sampled and analyzed.
[0043] Specifically, in the step S3, the heating temperature of the three-necked flask is 100 to 120 degrees Celsius, the reaction time is 4 to 8 hours, the reaction is stirred at a constant speed, and the temperature and pressure are monitored in real time.
[0044] Specifically, in step S4, after the reaction is completed and cooled, the reactants are filtered using activated carbon or silica gel to remove solid impurities and catalyst residues.
[0045] Specifically, in the steps S1, S2 and S3, before the reaction is carried out, the reaction kettle and the three-necked flask are dried and cleaned to ensure that no impurities remain.
[0046] Embodiment 2: This embodiment provides a method for preparing polyether modified silicone oil, comprising the following steps:
[0047] S1, adding hydrogen-containing silicone oil and ionic liquid catalyst into a reactor for heating reaction to obtain low hydrogen-containing silicone oil;
[0048] S2, mixing propylene oxide and propylene glycol, adding them together with sodium hydroxide into a reactor for heating reaction, adding acrylic acid after the reaction is completed and reacting to obtain an unsaturated polyether;
[0049] S3, adding the obtained low hydrogen silicone oil and unsaturated polyether into a three-necked flask, and adding chloroplatinic acid catalyst to carry out heating reaction;
[0050] S4. After the reaction is completed, the temperature is cooled to obtain polyether modified silicone oil.
[0051] Specifically, in step S3, the molar ratio of the low-hydrogen silicone oil to the unsaturated polyether is 1:1, and the proportion of the chloroplatinic acid catalyst is 0.1% to 0.5%.
[0052] Specifically, in step S1, the weight ratio of the hydrogen-containing silicone oil to the ionic liquid catalyst is 1:0.05 to 1:0.1, ensuring that the concentration of the ionic liquid is moderate.
[0053] Specifically, in step S1, the heating temperature of the reactor is 80 to 120 degrees Celsius, the reaction time is 3 to 5 hours, and uniform stirring is maintained during the reaction.
[0054] Specifically, in step S2, propylene oxide and propylene glycol are mixed in a molar ratio of 1:1, and the proportion of sodium hydroxide is 0.1% to 1%.
[0055] Specifically, in the step S2, the heating temperature of the reactor is 80 to 120 degrees Celsius, the pressure is maintained at 0.4 to 0.6 MPa, the reaction time is 4 to 6 hours, and uniform stirring is maintained during the reaction. After adding acrylic acid to the reactor, the reaction is continued for 1 to 2 hours, and the proportion of acrylic acid is 5% to 15%.
[0056] Specifically, after the reaction in step S2 is completed, the pressure of the reactor is reduced to 0.15-0.2 MPa, the temperature in the reactor is lowered and then emptied, the reactor is connected to a vacuum pump and evacuated, the temperature in the reactor is maintained at 65-75 degrees Celsius, and nitrogen, helium or argon is introduced to remove small molecules, the reaction product is taken out and naturally cooled, filtered with acidic clay, activated carbon or silica gel to remove solid impurities and catalyst residues, and the molecular weight and structure of the polyether are sampled and analyzed.
[0057] Specifically, in the step S3, the heating temperature of the three-necked flask is 100 to 120 degrees Celsius, the reaction time is 4 to 8 hours, the reaction is stirred at a constant speed, and the temperature and pressure are monitored in real time.
[0058] Specifically, in step S4, after the reaction is completed and cooled, the reactants are filtered using activated carbon or silica gel to remove solid impurities and catalyst residues.
[0059] Specifically, in the steps S1, S2 and S3, before the reaction is carried out, the reaction kettle and the three-necked flask are dried and cleaned to ensure that no impurities remain.
[0060] Embodiment 3: This embodiment provides a method for preparing polyether-modified silicone oil, comprising the following steps:
[0061] S1, adding hydrogen-containing silicone oil and ionic liquid catalyst into a reactor for heating reaction to obtain low hydrogen-containing silicone oil;
[0062] S2, mixing propylene oxide and propylene glycol, adding them together with sodium hydroxide into a reactor for heating reaction, adding acrylic acid after the reaction is completed and reacting to obtain an unsaturated polyether;
[0063] S3, adding the obtained low hydrogen silicone oil and unsaturated polyether into a three-necked flask, and adding chloroplatinic acid catalyst to carry out heating reaction;
[0064] S4. After the reaction is completed, the temperature is cooled to obtain polyether modified silicone oil.
[0065] Specifically, in step S3, the molar ratio of the low hydrogen silicone oil to the unsaturated polyether is 1:1.5, and the proportion of the chloroplatinic acid catalyst is 0.1% to 0.5%.
[0066] Specifically, in step S1, the weight ratio of the hydrogen-containing silicone oil to the ionic liquid catalyst is 1:0.05 to 1:0.1, ensuring that the concentration of the ionic liquid is moderate.
[0067] Specifically, in step S1, the heating temperature of the reactor is 80 to 120 degrees Celsius, the reaction time is 3 to 5 hours, and uniform stirring is maintained during the reaction.
[0068] Specifically, in step S2, propylene oxide and propylene glycol are mixed in a molar ratio of 1:1, and the proportion of sodium hydroxide is 0.1% to 1%.
[0069] Specifically, in the step S2, the heating temperature of the reactor is 80 to 120 degrees Celsius, the pressure is maintained at 0.4 to 0.6 MPa, the reaction time is 4 to 6 hours, and uniform stirring is maintained during the reaction. After adding acrylic acid to the reactor, the reaction is continued for 1 to 2 hours, and the proportion of acrylic acid is 5% to 15%.
[0070] Specifically, after the reaction in step S2 is completed, the pressure of the reactor is reduced to 0.15-0.2 MPa, the temperature in the reactor is lowered and then emptied, the reactor is connected to a vacuum pump and evacuated, the temperature in the reactor is maintained at 65-75 degrees Celsius, and nitrogen, helium or argon is introduced to remove small molecules, the reaction product is taken out and naturally cooled, filtered with acidic clay, activated carbon or silica gel to remove solid impurities and catalyst residues, and the molecular weight and structure of the polyether are sampled and analyzed.
[0071] Specifically, in the step S3, the heating temperature of the three-necked flask is 100 to 120 degrees Celsius, the reaction time is 4 to 8 hours, the reaction is stirred at a constant speed, and the temperature and pressure are monitored in real time.
[0072] Specifically, in step S4, after the reaction is completed and cooled, the reactants are filtered using activated carbon or silica gel to remove solid impurities and catalyst residues.
[0073] Specifically, in the steps S1, S2 and S3, before the reaction is carried out, the reaction kettle and the three-necked flask are dried and cleaned to ensure that no impurities remain.
[0074] As can be seen from the above, this design application is applied to the processing and preparation scenario of polyether-modified silicone oil. It is used for the processing and preparation of polyether-modified silicone oil. By adding hydrogen-containing silicone oil and ionic liquid catalyst into the reactor for heating reaction, such as 1-butyl-3-methylimidazole chloride, as a green catalyst, it has excellent solubility and catalytic activity, and can effectively remove moisture and other organic impurities in low-hydrogen silicone oil. The interaction between its cations and anions can break the combination of impurity molecules and the main reactants, thereby removing impurities in hydrogen-containing silicone oil and reducing the hydrogen content in hydrogen-containing silicone oil to generate low-hydrogen silicone oil with better thermal stability and reduced degradation risk in high-temperature applications;
[0075] Propylene oxide and propylene glycol are mixed, and added into a reactor together with sodium hydroxide for heating reaction. Propylene oxide is the main reactant of the polyetherification reaction. Propylene glycol provides alcohol groups, and its hydroxyl groups can form polymers with propylene oxide, improve the solubility and dispersibility of the polymer, and directly affect the molecular weight and viscosity of the product. The ring-opening reaction of propylene oxide is catalyzed by sodium hydroxide to increase the reaction rate, making the polyetherification reaction more efficient, so that propylene oxide reacts with propylene glycol through the ring-opening reaction to form polyether, and the oxygen atoms in its ring structure are opened under the action of sodium hydroxide to form a compound. The acrylic acid added after the reaction is completed is used to introduce unsaturated groups, increase the reactivity and cross-linking ability of the polyether, and enhance its physical and chemical stability. The reaction is continued to introduce a carbon-carbon unsaturated double bond at one end of the polyether, and its double bond structure can participate in cross-linking in subsequent reactions;
[0076] Finally, add them together with low-hydrogen silicone oil and chloroplatinic acid catalyst into a three-necked flask for reaction. During the reaction, the unsaturated bonds of the polyether can react with the silicon-hydrogen groups in the low-hydrogen silicone oil to form new covalent bonds. The chloroplatinic acid catalyst forms an active intermediate to provide the required activation energy, which helps to promote the addition reaction of silicon-hydrogen groups with unsaturated polyethers and increase the reaction rate, ultimately generating polyether-modified silicone oil. Since the two macromolecular intermediates, low-hydrogen silicone oil and unsaturated polyether, have small molecular weights and high activity, the content of chloroplatinic acid catalyst can be greatly reduced. Since low-hydrogen silicone oil contains a lower hydrogen content, it can more efficiently undergo cross-linking reaction with unsaturated polyethers, thereby producing a more stable and strong modified polymer, which does not even require the participation of chloroplatinic acid catalysts and is more environmentally friendly.
[0077] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, and parameter values (e.g., temperature, pressure, etc.), installation arrangement, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure of performing the function described herein, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to numerous modifications still falling within the scope of the appended claims.
[0078] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.
[0079] It will be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but will be a routine task of design, fabrication, and production for those of ordinary skill having the benefit of this disclosure without undue experimentation.
[0080] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.
Claims
1. A method for preparing a polyether-modified silicone oil, characterized in that: The following steps are involved: S1, adding hydrogen-containing silicone oil and ionic liquid catalyst into a reactor for heating reaction to obtain low hydrogen-containing silicone oil; S2, mixing propylene oxide and propylene glycol, adding them together with sodium hydroxide into a reactor for heating reaction, adding acrylic acid after the reaction is completed and reacting to obtain an unsaturated polyether; S3, adding the obtained low hydrogen silicone oil and unsaturated polyether into a three-necked flask, and adding chloroplatinic acid catalyst to carry out heating reaction; S4. After the reaction is completed, the temperature is cooled to obtain polyether modified silicone oil.
2. A method for preparing a polyether-modified silicone oil according to claim 1, characterized in that: In the step S3, the molar ratio of the low hydrogen silicone oil to the unsaturated polyether is 1:0.5 to 1:1.5, and the proportion of the chloroplatinic acid catalyst is 0.1% to 0.5%.
3. A method for preparing a polyether-modified silicone oil according to claim 1, characterized in that: In the step S1, the weight ratio of the hydrogen-containing silicone oil to the ionic liquid catalyst is 1:0.05 to 1:0.1, ensuring that the concentration of the ionic liquid is moderate.
4. A method for preparing a polyether-modified silicone oil according to claim 1, characterized in that: In step S1, the heating temperature of the reactor is 80 to 120 degrees Celsius, the reaction time is 3 to 5 hours, and uniform stirring is maintained during the reaction.
5. A method for preparing a polyether-modified silicone oil according to claim 1, characterized in that: In the step S2, propylene oxide and propylene glycol are mixed in a molar ratio of 1:1, and the proportion of sodium hydroxide is 0.1% to 1%.
6. A method for preparing a polyether-modified silicone oil according to claim 1, characterized in that: In the step S2, the heating temperature of the reactor is 80-120 degrees Celsius, the pressure is maintained at 0.4-0.6 MPa, the reaction time is 4-6 hours, and uniform stirring is maintained during the reaction. After adding acrylic acid to the reactor, the reaction is continued for 1-2 hours, and the proportion of acrylic acid is 5%-15%.
7. A method for preparing a polyether-modified silicone oil according to claim 1, characterized in that: After the reaction in step S2 is completed, the pressure of the reactor is reduced to 0.15-0.2 MPa, the temperature in the reactor is lowered and then emptied, the reactor is connected to a vacuum pump and evacuated, the temperature in the reactor is maintained at 65-75 degrees Celsius, and nitrogen, helium or argon is introduced to remove small molecules, the reaction product is taken out and naturally cooled, filtered with acidic clay, activated carbon or silica gel to remove solid impurities and catalyst residues, and the molecular weight and structure of the polyether are analyzed by sampling.
8. A method for preparing a polyether-modified silicone oil according to claim 1, characterized in that: In the step S3, the heating temperature of the three-necked flask is 100 to 120 degrees Celsius, the reaction time is 4 to 8 hours, and the stirring is maintained at a constant speed during the reaction, and the temperature and pressure are monitored in real time.
9. A method for preparing a polyether-modified silicone oil according to claim 1, characterized in that: In the step S4, after the reaction is completed and cooled, the reactants are filtered using activated carbon or silica gel to remove solid impurities and catalyst residues.
10. The method for preparing a polyether-modified silicone oil according to claim 1, characterized in that: In the steps S1, S2 and S3, before the reaction is carried out, the reaction kettle and the three-necked flask are dried and cleaned to ensure that no impurities remain.