A process for the preparation of a phenylsilane polymer

Abstract

The application relates to the technical field of organic synthesis, in particular to a preparation process of a phenyl silane polymer; the application successfully introduces a phenyl group on a silane polymer skeleton through a two-step method; after the two-step reaction, purification means such as reduced pressure distillation are adopted, so that byproducts, unreacted raw materials and solvents generated in the reaction can be effectively removed, and high yield and high purity of the final product are ensured; furthermore, the introduction of the phenyl group significantly improves the heat resistance of the final polymer, so that the thermal decomposition temperature of the final polymer is greatly improved; meanwhile, the rigid structure of the phenyl group enhances the mechanical strength of the polymer, and the hydrophobicity and the compatibility with various materials are also improved, so that the polymer can be widely used for preparing high-temperature-resistant protective coatings, high-refractive optical materials, high-performance silicone rubber and packaging protective materials of electronic components, and the demand of high-end manufacturing industry for special organic silicon materials is met.

Description

Technical Field

[0001] This invention relates to the field of organic synthesis technology, specifically to a preparation process for a phenylsilane polymer. Background Technology

[0002] Organosilicon polymers are widely used in aerospace, electronics, construction, and medical fields due to their excellent high and low temperature resistance, weather resistance, electrical insulation, and low surface tension. Among them, phenylsilane polymers, due to the introduction of phenyl functional groups into their molecular chains, achieve significantly improved performance compared to ordinary methylsilane polymers. The introduction of phenyl not only greatly improves the polymer's heat and oxidation stability, enabling long-term use at higher temperatures, but also improves its compatibility with other organic polymers and inorganic fillers. Simultaneously, the large benzene ring structure enhances the rigidity of the molecular chain, giving the material superior mechanical strength and refractive index.

[0003] Currently, the synthesis methods for phenylsilane polymers face the following technical challenges:

[0004] 1. Directly using organosilicon monomers containing phenyl groups (such as diphenyldimethoxysilane) for co-hydrolysis and polycondensation can introduce phenyl groups, but such monomers are expensive, their reactivity is difficult to control, and the resulting polymers have a simple structure and a narrow range of adjustable properties.

[0005] 2. Another approach is to graft phenyl groups onto the pre-synthesized polysiloxane backbone through post-functionalization. However, this approach often faces problems such as low reaction efficiency, numerous side reactions, and unclear product structure, which affect the purity and performance stability of the final product.

[0006] Based on the above, the present invention provides a preparation process for phenylsilane polymers to solve the aforementioned technical problems. Summary of the Invention

[0007] The purpose of this invention is to provide a preparation process for phenylsilane polymers. The prepared phenylsilane polymers not only have high yields, but also few byproducts and high purity, effectively ensuring their quality. Furthermore, the preparation process provided by this invention has mild conditions, relatively few steps, and is easy to operate, effectively saving production costs.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A process for preparing a phenylsilane polymer includes the following steps:

[0010] Step 1: Add the organosilane and mixed solvent to the reactor at a mass ratio of 3-5:1. Mix them uniformly at a speed of 300-500 r / min. Then add the catalyst to the resulting mixture, stir until homogeneous, and heat to 60-80℃. Maintain this temperature and stir for 5-8 hours. After the reaction is complete, purify the product components by vacuum distillation. Store the obtained silane polymer for later use.

[0011] Step 2: Under the protection of an inert gas, add the silane polymer to an organic solvent with a mass of 5-8 times its weight, mix and stir evenly, then add benzyl halide with a molar amount of 1-2 times that of the silane polymer and an alkaline reagent with a molar amount of 3-4 times its weight. After refluxing for 15-20 hours, cool the reaction product to room temperature, and then successively filter, extract with ethyl acetate and distill under reduced pressure to remove ethyl acetate and benzyl halide from the reaction product. The resulting oily liquid is the phenylsilane polymer.

[0012] Furthermore, the mixed solvent is prepared by mixing an organic solvent and deionized water in a volume ratio of 3-5:1; and the organic solvent is selected from any one of methanol, ethanol, and isopropanol.

[0013] Furthermore, the organosilane is selected from at least two or more combinations of 3-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-aminoethyl-γ-aminopropyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, and N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane.

[0014] Furthermore, the catalyst is industrial hydrochloric acid, and its dosage is 1-2 wt% of the organosilane.

[0015] Furthermore, the benzyl halide is selected from either benzyl chloride or benzyl bromide.

[0016] Furthermore, the alkaline reagent is triethylamine.

[0017] Furthermore, the inert gas is any one of nitrogen, helium, or argon.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] 1. This invention successfully introduces phenyl groups into the backbone of a silane polymer using a two-step method. Both steps employ purification methods such as vacuum distillation to effectively remove byproducts, unreacted raw materials, and solvents generated during the reaction, ensuring the purity and quality stability of the final product, which is beneficial for industrial production. Furthermore, the introduction of phenyl groups significantly improves the heat resistance of the final polymer, substantially increasing its thermal decomposition temperature. Simultaneously, the rigid structure of the phenyl group enhances the polymer's mechanical strength, while its hydrophobicity and compatibility with various materials are also improved. This allows for wide application in the preparation of high-temperature protective coatings, high-refractive-index optical materials, high-performance silicone rubber, and encapsulation and protective materials for electronic components, meeting the demand for special organosilicon materials in high-end manufacturing industries.

[0020] 2. This invention employs hydrolysis and condensation under acidic conditions and, by controlling the type and proportion of organosilanes, can flexibly regulate the molecular chain structure and number of active sites of the intermediate polymer, laying the structural foundation for the second-step phenylation reaction. Furthermore, the reaction with benzyl halide under an inert atmosphere results in mild conditions, fewer side reactions, and ensures the efficiency and high selectivity of phenyl introduction.

[0021] 3. Compared with the direct use of expensive diphenylsiloxane monomers, this invention mainly uses common and low-cost aminosilanes as starting materials, and introduces phenyl groups through subsequent efficient phenylation reactions, which effectively reduces the cost of raw materials while ensuring performance. Detailed Implementation

[0022] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0023] Example 1

[0024] A process for preparing a phenylsilane polymer includes the following steps:

[0025] Step 1: Add organosilane and mixed solvent to the reactor at a mass ratio of 3:1. Mix them uniformly at a speed of 300 r / min. Then add the catalyst to the resulting mixture, stir until uniform, and heat to 60℃. Keep the mixture at this temperature and stir for 8 hours. After the reaction is complete, purify the product components by vacuum distillation. Store the obtained silane polymer for later use.

[0026] The mixed solvent is composed of an organic solvent and deionized water in a volume ratio of 3:1; and the organic solvent used is methanol.

[0027] The organosilane is composed of equimolar amounts of 3-aminopropyltrimethoxysilane and γ-aminopropyltriethoxysilane;

[0028] The catalyst used is industrial hydrochloric acid, and its dosage is 1 wt% of the organosilane.

[0029] Step 2: Under nitrogen protection, the silane polymer is added to an organic solvent with a mass of 5 times its weight. After mixing and stirring evenly, benzyl chloride with a molar amount of 1 times that of the silane polymer and triethylamine with a molar amount of 3 times that of the silane polymer are added. After refluxing for 15 hours, the reaction product is cooled to room temperature and then successively filtered, extracted with ethyl acetate, and distilled under reduced pressure to remove ethyl acetate and benzyl chloride from the reaction product. The resulting oily liquid is the phenylsilane polymer.

[0030] Example 2

[0031] A process for preparing a phenylsilane polymer includes the following steps:

[0032] Step 1: Add organosilane and mixed solvent to the reactor at a mass ratio of 4:1. Mix them uniformly at a speed of 400 r / min. Then add the catalyst to the resulting mixture, stir until homogeneous, and heat to 70℃. Keep the mixture at this temperature and stir for 6 hours. After the reaction is complete, purify the product components by vacuum distillation. Store the obtained silane polymer for later use.

[0033] The mixed solvent is composed of an organic solvent and deionized water in a volume ratio of 4:1; and the organic solvent is ethanol.

[0034] The organosilane is composed of equimolar amounts of 3-aminopropyltrimethoxysilane and N-aminoethyl-γ-aminopropyltriethoxysilane;

[0035] The catalyst used is industrial hydrochloric acid, and its dosage is 1.5 wt% of the organosilane.

[0036] Step 2: Under helium protection, the silane polymer is added to an organic solvent with a mass of 6 times its weight. After mixing and stirring evenly, benzyl bromide with a molar amount of 1.5 times that of the silane polymer and triethylamine with a molar amount of 3 times their weight are added. After refluxing for 15 hours, the reaction product is cooled to room temperature and then subjected to filtration, ethyl acetate extraction and vacuum distillation to remove ethyl acetate and benzyl bromide from the reaction product. The resulting oily liquid is the phenylsilane polymer.

[0037] Example 3

[0038] A process for preparing a phenylsilane polymer includes the following steps:

[0039] Step 1: Add organosilane and mixed solvent to the reactor at a mass ratio of 5:1. Mix them uniformly at a speed of 500 r / min. Then add the catalyst to the resulting mixture, stir until uniform, and heat to 80℃. Keep the mixture at this temperature and stir for 5 hours. After the reaction is complete, purify the product components by vacuum distillation. Store the obtained silane polymer for later use.

[0040] The mixed solvent is composed of an organic solvent and deionized water in a volume ratio of 5:1; and the organic solvent is isopropanol.

[0041] The organosilane is composed of equimolar amounts of γ-aminopropyltriethoxysilane and N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane;

[0042] The catalyst used is industrial hydrochloric acid, and its dosage is 2 wt% of the organosilane.

[0043] Step 2: Under the protection of argon, the silane polymer is added to an organic solvent with a mass of 8 times its weight. After mixing and stirring evenly, benzyl chloride with a molar amount of 2 times that of the silane polymer and triethylamine with a molar amount of 4 times that of the silane polymer are added. After refluxing for 20 hours, the reaction product is cooled to room temperature and then successively filtered, extracted with ethyl acetate and distilled under reduced pressure to remove ethyl acetate and benzyl chloride from the reaction product. The resulting oily liquid is the phenylsilane polymer.

[0044] Performance testing: The yield and purity of the phenylsilane polymer samples prepared in Examples 1-3 were tested, and the test data are recorded in the table below:

[0045]

[0046] By comparing and analyzing the data in the table, it can be seen that the purpose of this invention is to provide a preparation process for phenylsilane polymers. The prepared phenylsilane polymers not only have high yields but also few byproducts and high purity, effectively ensuring their quality. Furthermore, the preparation process provided by this invention has mild conditions, relatively few steps, and is easy to operate, effectively saving production costs. Therefore, this invention's preparation process for phenylsilane polymers has a broader market prospect and is more suitable for widespread application.

[0047] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0048] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A preparation process for a phenylsilane polymer, characterized in that, Includes the following steps: Step 1: Add the organosilane and mixed solvent to the reactor at a mass ratio of 3-5:

1. Mix them uniformly at a speed of 300-500 r / min. Then add the catalyst to the resulting mixture, stir until homogeneous, and heat to 60-80℃. Maintain this temperature and stir for 5-8 hours. After the reaction is complete, purify the product components by vacuum distillation. Store the obtained silane polymer for later use. Step 2: Under the protection of an inert gas, add the silane polymer to an organic solvent with a mass of 5-8 times its weight, mix and stir evenly, then add benzyl halide with a molar amount of 1-2 times that of the silane polymer and an alkaline reagent with a molar amount of 3-4 times its weight. After refluxing for 15-20 hours, cool the reaction product to room temperature, and then successively filter, extract with ethyl acetate and distill under reduced pressure to remove ethyl acetate and benzyl halide from the reaction product. The resulting oily liquid is the phenylsilane polymer.

2. The preparation process of a phenylsilane polymer according to claim 1, characterized in that: The mixed solvent is prepared by mixing an organic solvent and deionized water in a volume ratio of 3-5:1; and the organic solvent is selected from any one of methanol, ethanol, and isopropanol.

3. The preparation process of a phenylsilane polymer according to claim 1, characterized in that: The organosilane is selected from at least two or more combinations of 3-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-aminoethyl-γ-aminopropyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, and N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane.

4. The preparation process of a phenylsilane polymer according to claim 1, characterized in that: The catalyst is industrial hydrochloric acid, and its dosage is 1-2 wt% of the organosilane.

5. The preparation process of a phenylsilane polymer according to claim 1, characterized in that: The benzyl halide is selected from either benzyl chloride or benzyl bromide.

6. The preparation process of a phenylsilane polymer according to claim 1, characterized in that: The alkaline reagent used is triethylamine.

7. The preparation process of a phenylsilane polymer according to claim 1, characterized in that: The inert gas is any one of nitrogen, helium, or argon.

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