Vinyl-terminated silicone oil and preparation method thereof

Abstract

The invention discloses vinyl-terminated silicone oil and a preparation method thereof, siloxane, a vinyl end-capping reagent and an acid catalyst are mixed and react for a period of time, the vinyl-terminated silicone oil is obtained after impurity removal, filtration and low-temperature removal, and the acid catalyst is concentrated sulfuric acid, methanesulfonic acid or solid acid. According to the vinyl-terminated silicone oil prepared by the method, the content of polar impurities in a target product can be effectively reduced, purer vinyl-terminated silicone oil is obtained, the electrical insulating property and stability of the vinyl-terminated silicone oil are higher, and the vinyl-terminated silicone oil can be applied to the electronic and electrical industry with higher requirements.

Description

Technical Field

[0001] The present application relates to the field of silicone oil, and in particular to a vinyl-terminated silicone oil and a preparation method thereof. Background Art

[0002] Vinyl silicone oil is an organic silicon compound with a structure in which a vinyl group is connected to a silicon-oxygen bond. It is obtained by reacting compounds containing vinyl and silane functional groups. It has good stability, high temperature resistance and chemical stability, and can improve the adhesion and adhesion of materials.

[0003] Vinyl silicone oil has a wide range of applications. It is the main raw material for addition-type liquid silicone rubber, silicone gel and other products, and plays an important role in compound rubber modifiers, plastic additives and reinforcing materials. Vinyl silicone oil plays a vital role in the electronics industry with its unique chemical structure and physical properties. It is also widely used in cosmetics, medicine, lubricants, bearing lubricants, sealing materials, inks, plastics and rubber.

[0004] Low-viscosity vinyl silicone oil is often used in surface lubricants, rubber processing aids, waterproofing agents, buffer media and other fields due to its good fluidity. It is very suitable for coating and painting of high-end products such as silicon wafers, semiconductors, optical fibers, and avionics. Low-volatile vinyl silicone oil is widely used in many industries, especially in areas with strict requirements on volatile content, such as potting materials for electronic devices. Its low viscosity helps the potting operation while ensuring the electrical insulation of the potting compound. Summary of the invention

[0005] The purpose of the present application is to reduce the content of polar impurities in vinyl-terminated silicone oil.

[0006] In order to achieve the above purpose, the technical solution adopted in the present application is: to provide a method for preparing vinyl-terminated silicone oil, siloxane, a vinyl capping agent and an acid catalyst are mixed and reacted for a period of time, and the vinyl-terminated silicone oil is obtained after impurity removal, filtration and desulfurization, and the acid catalyst is concentrated sulfuric acid, methanesulfonic acid or solid acid.

[0007] Preferably, the solid acid is any one of acidic clay, molecular sieve, cation exchange resin, acidic oxide, sulfide or heteropolyacid, or a combination of more than one thereof.

[0008] As another preferred embodiment, the usage of the raw materials is: 200 to 300 parts by mass of the siloxane, 2 to 10 parts by mass of the vinyl end-capping agent, and 1 to 10 parts by mass of the acid catalyst.

[0009] As another preference, the mass ratio of the vinyl end-capping agent to the acid catalyst is 2:(1-5).

[0010] As another preference, the mass ratio of the siloxane to the acid catalyst is (100-30):1.

[0011] As another preference, the reaction temperature of the siloxane, the vinyl end-capping agent and the acid catalyst is below 100°C.

[0012] As another preference, the reaction temperature of the siloxane, the vinyl end-capping agent and the acid catalyst is 30-80°C.

[0013] As another preference, the reaction time of the siloxane, the vinyl end-capping agent and the acid catalyst is 2 to 4 hours.

[0014] More preferably, after the siloxane, the vinyl end-capping agent and the acid catalyst are mixed and reacted, a base is added to the mixture and stirred for reaction for 0.5 to 1 hour to remove the excess acid catalyst.

[0015] The present application also provides a vinyl-terminated silicone oil, which is prepared by any of the above-mentioned preparation methods.

[0016] Compared with the prior art, the beneficial effects of this application are:

[0017] (1) The present application prepares vinyl-terminated silicone oil by using siloxane, vinyl capping agent and acid catalyst, which can avoid other catalysts from increasing the content of polar impurities in silicone oil, thereby reducing the content of polar impurities in the prepared vinyl-terminated silicone oil and making it more pure;

[0018] (2) The present application uses an acid catalyst to catalyze the reaction of siloxane and a vinyl end-capping agent, thereby reducing the content of polar impurities such as terminal hydroxyl groups of silicone oil in the polymerization reaction, thereby achieving the purpose of reducing the content of polar impurities in the obtained vinyl-terminated silicone oil. DETAILED DESCRIPTION

[0019] Below, the present application is further described in conjunction with specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0020] The terms "including" and "having" and any variations thereof in the specification and claims of this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or apparatuses.

[0021] The present application provides a vinyl-terminated silicone oil, the preparation raw materials of which include: siloxane, a vinyl-terminated agent and an acid catalyst.

[0022] The vinyl-terminated silicone oil of the present application can effectively reduce polar impurities in the product, form vinyl silicone oil with higher purity, and avoid the viscosity problem of silicone oil caused by impurities.

[0023] The acid catalyst may be, but is not limited to, concentrated sulfuric acid, methanesulfonic acid, and solid acid.

[0024] In some embodiments, the ratio of the vinyl end-capping agent to the acid catalyst is 2:(1-5).

[0025] In some embodiments, the solid acid can be acid clay, molecular sieve, cation exchange resin, acidic oxide, sulfide or heteropoly acid, etc.

[0026] Acidic clay, also known as natural bleaching earth, is mainly a product of the decomposition of glassy volcanic rocks. It does not swell after absorbing water, and the pH value of the suspension is weakly acidic, which is different from alkaline bentonite. The chemical composition of acidic clay is similar to that of ordinary clay. The main chemical components are aluminum oxide, silicon dioxide, water and a small amount of iron, magnesium, calcium, etc. It has no plasticity and has high adsorption. Because it contains a large amount of hydrous silicate, it is acidic to litmus. It is easy to decompose in water and has a large water content. Generally, the finer the fineness, the higher the decolorization power.

[0027] In some embodiments, the molecular sieve may be any one or a combination of HZSM-5, SAPO-5, Sn-Beta, ZSM-5, SAPO-34, Al-SBA-15, or Ga-SBA-15.

[0028] HZSM-5 molecular sieve is a solid acid molecular sieve catalyst, which is widely used in catalytic cracking, methanol to olefins, methanol to gasoline and other industrial processes. The acid sites provided by the framework aluminum are its main catalytic active sites. The acidity of SAPO-5 molecular sieve depends on the difference between silicon-substituted phosphorus and aluminum atoms, and its acidic properties are very important in the catalytic process.

[0029] ZSM-5 molecular sieve is a common acidic molecular sieve used in a variety of catalytic reactions, including isomerization, alkylation, etc. SAPO-34 molecular sieve: SAPO-34 molecular sieve has acidic properties. and Lewis acid sites.

[0030] In some embodiments, the cation exchange resin can be: Amberlyst 15, Nafion H-type resin, DH-type resin, 732-type resin, D72-type resin, Amberlyst series resin or NKC-9 resin. These resins are easily dissociated into H in solution due to their strong acidic groups, such as sulfonic acid group -SO3H.+ , so it is strongly acidic and is widely used in water treatment, organic synthesis, separation treatment, environmental protection and biopharmaceuticals.

[0031] Amberlyst 15 is a strong acid resin, a sulfonated polystyrene-divinylbenzene copolymer, which is widely used as an acid catalyst in fine organic synthesis, especially in esterification and alkylation reactions. Amberlyst series resins include Amberlyst 35, Amberlyst 39, etc., which have a good catalytic effect on acid-catalyzed reactions.

[0032] In some embodiments, the acidic oxide is silicon dioxide, aluminum oxide, phosphorus pentoxide, manganese heptoxide, iron oxide, vanadium pentoxide, titanium dioxide, or nitrogen dioxide.

[0033] In some embodiments, the sulfide may be one or a combination of cadmium sulfide, zinc sulfide, cobalt sulfide, molybdenum disulfide, or metal sulfides.

[0034] Solid heteropolyacids are compounds formed by condensation of different types of oxygen-containing acid anions. They have a Keggin structure and are widely used as catalysts in various chemical reactions. In some embodiments, the heteropolyacid is dodecaphosphotungstic acid, dodecasilicotungstic acid, 11-sodium molybdenum silicate, NH4[Fe(OH)6Mo6O 18 ]、Na3Fe(OH)6Mo6O 18 Any one or a combination of 5H2O.

[0035] Dodecaphosphotungstic acid and dodecasilicotungstic acid are both commonly used heteropoly acids with Keggin structure, which are widely used in reactions such as esterification, alkylation, transesterification and olefin epoxidation. These heteropoly acids have shown wide application potential in the field of catalysis due to their unique structure and properties, especially in redox reactions, esterification reactions, alkylation reactions and other processes.

[0036] The present application uses siloxane, a vinyl end-capping agent and an acid catalyst to prepare a high-purity vinyl-terminated silicone oil, which can effectively reduce polar impurities in the vinyl-terminated silicone oil. The purity of the vinyl silicone oil will directly affect the performance of its downstream products, and the high-purity vinyl silicone oil can ensure that the prepared products have better physical and chemical properties, such as transparency, stability and durability.

[0037] In the electronics industry, high purity of vinyl silicone oil is particularly important. Electronic grade vinyl silicone oil requires higher purity and usually has lower impurity content, especially lower organic matter and metal ion content, which is crucial to ensure the performance and reliability of electronic products. In the fields of medicine and cosmetics, high purity vinyl silicone oil can reduce potential harm to the human body and improve the safety and reliability of products.

[0038] In summary, the purity of vinyl silicone oil is crucial to ensure its performance and safety in various application fields. High-purity vinyl silicone oil can provide better product performance, reduce side reactions, improve production efficiency, reduce energy consumption and environmental impact, meet specific industrial standards, and improve product safety and reliability.

[0039] In some embodiments, the siloxane may be octamethylcyclotetrasiloxane, tetramethyltetravinylcyclotetrasiloxane, vinyltrimethoxysilane, divinyltetramethyldisiloxane, 1,1,3,3,-tetramethyl-1,3-divinylsiloxane.

[0040] The present application also provides a method for preparing vinyl-terminated silicone oil: siloxane, a vinyl-capping agent and an acid catalyst are mixed and reacted for a period of time, and then the vinyl-terminated silicone oil is obtained after impurities are removed, filtration and desulfurization.

[0041] In some embodiments, the amount of each raw material is calculated by weight: 200-300 parts by weight of siloxane, 2-10 parts by weight of vinyl end-capping agent, and 1-10 parts by weight of acid catalyst.

[0042] In some embodiments, the ratio of the vinyl end-capping agent to the acid catalyst is 2:(1-5).

[0043] In some embodiments, the mass ratio of siloxane to acid catalyst is (100-30):1.

[0044] In some embodiments, the reaction temperature is 30-80° C., and the reaction time is 2-4 h.

[0045] In some embodiments, after the reaction of siloxane, vinyl capping agent and acid catalyst, a base is added for neutralization and stirred for 0.5 to 1 hour. The product is then filtered, deoxidized and treated to obtain the vinyl-terminated silicone oil of the present application.

[0046] Polar impurities in vinyl silicone oil, such as residual Si-OH, -C-OH and -C=O groups, increase the interaction between molecules, resulting in increased viscosity. These polar groups can form hydrogen bonds or other types of intermolecular forces, which enhance the attraction between molecules, reduce the fluidity of silicone oil and increase viscosity.

[0047] Therefore, the present application indirectly reflects the content of polar impurities in the sample by characterizing the thickening viscosity of the vinyl-terminated silicone oil sample, wherein the higher the content of polar impurities, the greater the thickening viscosity of the vinyl-terminated silicone oil.

[0048] Performance Testing Methods

[0049] Thickening viscosity: Weigh 20g of sample and add 3% 107 glue curing agent and stir evenly. Let it stand for 24 hours in an environment with a temperature of 25±2℃ and a humidity of 55%±5%. Observe the sample for any caking and fluidity, and record the results.

[0050] Example 1

[0051] A vinyl-terminated silicone oil was prepared according to the following preparation steps: 300 g of octamethylcyclotetrasiloxane, 5 g of a vinyl-terminated agent and 3 g of concentrated sulfuric acid were weighed in a container, reacted at 35° C. for 2 to 4 h, and then 4 g of sodium carbonate was added for neutralization. The mixture was stirred for 0.5 to 1 h, and the vinyl-terminated silicone oil of Example 1 was obtained after filtering, desulfurization and other treatments.

[0052] According to the performance test, the viscosity of the vinyl-terminated silicone oil prepared in Example 1 is 352 mm 2 / s, the thickening viscosity test was 24h without agglomeration, good fluidity, and the thickening viscosity was 3402mm 2 / s.

[0053] Example 2

[0054] A vinyl-terminated silicone oil was prepared according to the following preparation steps: 300 g of octamethylcyclotetrasiloxane, 5 g of a vinyl-terminated agent and 3 g of methanesulfonic acid were weighed in a container, reacted at 35° C. for 2 to 4 h, and then 4 g of sodium carbonate was added for neutralization. The mixture was stirred for 0.5 to 1 h, and the vinyl-terminated silicone oil of Example 2 was obtained after filtering, desulfurization and other treatments.

[0055] According to the performance test, the viscosity of the vinyl-terminated silicone oil prepared in Example 2 is 355 mm 2 / s, the thickening viscosity test was 24h without agglomeration, good fluidity, and the thickening viscosity was 3356mm 2 / s.

[0056] Example 3

[0057] A vinyl-terminated silicone oil was prepared according to the following preparation steps: 300 g of octamethylcyclotetrasiloxane, 5 g of a vinyl-terminated agent and 10 g of a solid acid were weighed in a container, reacted at 35° C. for 2 to 4 h, and the vinyl-terminated silicone oil of Example 3 was obtained after filtering and desulfurization.

[0058] According to the performance test, the viscosity of the vinyl-terminated silicone oil prepared in Example 3 is 353 mm 2 / s, the thickening viscosity test was 24h without agglomeration, good fluidity, and the thickening viscosity was 3026mm 2 / s.

[0059] Example 4

[0060] A vinyl-terminated silicone oil was prepared according to the following preparation steps: 300 g of octamethylcyclotetrasiloxane, 5.2 g of a vinyl-terminated agent and 10 g of a solid acid were weighed in a container, reacted at 80° C. for 2 to 4 h, and the vinyl-terminated silicone oil of Example 4 was obtained after filtering and desulfurization.

[0061] According to the performance test, the viscosity of the vinyl-terminated silicone oil prepared in Example 4 is 315 mm 2 / s, the thickening viscosity test was conducted for 24 hours without any agglomeration, good fluidity, and the thickening viscosity was 2964mm 2 / s.

[0062] Example 5

[0063] A vinyl-terminated silicone oil was prepared according to the following preparation steps: 300 g of octamethylcyclotetrasiloxane, 4.85 g of a vinyl-terminated agent and 10 g of a solid acid were weighed in a container, reacted at 80° C. for 2 to 4 h, and the vinyl-terminated silicone oil of Example 5 was obtained after filtering and desulfurization.

[0064] According to the performance test, the viscosity of the vinyl-terminated silicone oil prepared in Example 5 is 385 mm 2 / s, the thickening viscosity test was 24h without agglomeration, good fluidity, and the thickening viscosity was 3218mm 2 / s.

[0065] Comparative Example 1

[0066] A vinyl-terminated silicone oil was prepared according to the following preparation steps: 300 g of octamethylcyclotetrasiloxane, 5 g of a vinyl-terminated agent and 15 ppm of tetramethylammonium hydroxide were weighed in a container, reacted at 100° C. for 1 to 2 h, and the vinyl-terminated silicone oil of Comparative Example 1 was obtained after treatments such as breaking the catalyst and removing the low-carbon radical.

[0067] According to the performance test, the viscosity of the vinyl-terminated silicone oil prepared in Comparative Example 1 is 354 mm 2 / s, the thickening viscosity test showed agglomeration and poor fluidity after 24 hours, and the thickening viscosity was 4420mm 2 / s.

[0068] Comparative Example 2

[0069] A vinyl-terminated silicone oil was prepared according to the following preparation steps: 300 g of octamethylcyclotetrasiloxane, 5 g of a vinyl-terminated agent and 15 ppm of potassium hydroxide were weighed in a container, reacted at 145° C. for 1 to 2 h, and the vinyl-terminated silicone oil of Comparative Example 2 was obtained after treatments such as breaking the catalyst and removing the low-carbon radical.

[0070] According to the performance test, the viscosity of the vinyl-terminated silicone oil prepared in Comparative Example 2 is 348 mm 2 / s, the thickening viscosity test showed serious agglomeration and poor fluidity for 24 hours, and the thickening viscosity was 5142mm 2 / s.

[0071] Analyzing the performance test results of the above embodiments and comparative examples, the embodiments use siloxane, vinyl end-capping agent and acid catalyst for reaction, while the comparative example uses siloxane, vinyl end-capping agent and base catalyst for reaction, respectively obtaining different vinyl-terminated silicone oils, and their viscosities are not much different.

[0072] The thickening viscosity test results of the examples and comparative examples are analyzed, and the thickening viscosity values ​​of the vinyl-terminated silicone oils prepared in comparative examples 1 and 2 are significantly higher than those of the vinyl-terminated silicone oils prepared in the examples. This phenomenon shows that the vinyl-terminated silicone oil prepared in the present application has a higher purity and contains fewer polar impurities, which helps to obtain vinyl-terminated silicone oils with better electrical insulation and stability, and has better effects in the application of the electronics industry.

[0073] The performance test results of Examples 1 to 3 were analyzed. Different acid catalysts were used in each Example, concentrated sulfuric acid in Example 1, methanesulfonic acid in Example 2, and solid acid in Example 3. The viscosity of the vinyl-terminated silicone oils prepared in each Example was not much different, but there were certain differences in the thickening viscosity. The vinyl-terminated silicone oil prepared using solid acid as the acid catalyst had the smallest thickening viscosity. Therefore, it can be inferred that the content of polar impurities in the vinyl-terminated silicone oil in Example 3 is even lower.

[0074] The performance test results of Example 1, Example 4 and Example 5 were analyzed, in which the amount of the vinyl end-capping agent was changed. The viscosity of the vinyl-terminated silicone oil prepared in Example 4 was the smallest and the thickening viscosity was the smallest. This phenomenon shows that the ethylene end-capping agent has a greater impact on the content of polar impurities in the product vinyl-terminated silicone oil, and increasing the amount of the ethylene end-capping agent is beneficial to reducing the content of polar impurities in the product vinyl-terminated silicone oil.

[0075] In the process of preparing vinyl-terminated silicone oil, the present application uses an acid catalyst, which can not only avoid the increase of the content of polar impurities in the silicone oil by catalysts such as tetramethylammonium hydroxide or potassium hydroxide, but also reduce the content of polar impurities such as terminal hydroxyl groups of the silicone oil in the polymerization reaction, thereby achieving the purpose of reducing the content of polar impurities in the vinyl-terminated silicone oil.

[0076] In summary, the present application prepares vinyl-terminated silicone oil by reacting siloxane, a vinyl capping agent and an acid catalyst, which can effectively reduce the content of polar impurities in the product vinyl-terminated silicone oil, obtain a purer vinyl-terminated silicone oil, and make the electrical insulation and stability of the vinyl-terminated silicone oil stronger, so that it can be used in the electronic and electrical industries with higher requirements.

[0077] The above describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited by the above embodiments, and the above embodiments and the specification only describe the principles of the present application. The present application may have various changes and improvements without departing from the spirit and scope of the present application, and these changes and improvements fall within the scope of the present application for which protection is sought. The scope of protection claimed by the present application is defined by the attached claims and their equivalents.

Claims

1. A method for preparing vinyl-terminated silicone oil, characterized in that: Siloxane, a vinyl end-capping agent and an acid catalyst are mixed and reacted for a period of time, and the vinyl-terminated silicone oil is obtained after impurity removal, filtration and desulfurization. The acid catalyst is concentrated sulfuric acid, methanesulfonic acid or solid acid.

2. The preparation method according to claim 1, characterized in that The solid acid is any one of acidic clay, molecular sieve, cation exchange resin, acidic oxide, sulfide or heteropoly acid or a combination of multiple thereof.

3. The preparation method according to claim 1, characterized in that: The usage of each raw material is: 200-300 parts by weight of the siloxane, 2-10 parts by weight of the vinyl end-capping agent, and 1-10 parts by weight of the acid catalyst.

4. The preparation method according to claim 3, characterized in that: The mass ratio of the vinyl end-capping agent to the acid catalyst is 2:(1-5).

5. The preparation method according to claim 3, characterized in that: The mass ratio of the siloxane to the acid catalyst is (100-30):

1.

6. The preparation method according to claim 1, characterized in that: The reaction temperature of the siloxane, the vinyl end-capping agent and the acid catalyst is below 100°C.

7. The preparation method according to claim 4, characterized in that: The reaction temperature of the siloxane, the vinyl end-capping agent and the acid catalyst is 30 to 80°C.

8. The preparation method according to claim 5, characterized in that: The reaction time of the siloxane, the vinyl end-capping agent and the acid catalyst is 2 to 4 hours.

9. The preparation method according to claim 1, characterized in that: After the siloxane, the vinyl end-capping agent and the acid catalyst are mixed and reacted, a base is added to the mixture and stirred for reaction for 0.5 to 1 hour to remove the excess acid catalyst.

10. A vinyl-terminated silicone oil, characterized in that: The method is used as claimed in any one of claims 1 to 9.