A high-boron-content polymer, a preparation method and application thereof
By preparing high-boron-content polymers at low temperatures, the problems of toxicity and high synthesis difficulty of traditional boron sources have been solved, achieving efficient and safe polymer synthesis suitable for high-temperature ablation-resistant applications.
Patent Information
- Application Number
- CN202411125574.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-16
- Publication Date
- 2026-02-27
- Estimated Expiration
- 2044-08-16
AI Technical Summary
In the existing technology, the boron source reactants used in the preparation of boron-containing polymers are toxic, have low boron content, and are difficult to synthesize. In addition, the traditional synthesis process is complex and difficult to achieve efficient mass production.
Under nitrogen or argon protection, polysilazane is dissolved in an organic solvent, and ammonia borane is added to react at -10℃ to 0℃. High boron content polymers are prepared by low-temperature liquid-phase assisted synthesis, which avoids the influence of inorganic elements such as chlorine and sulfur in traditional boron sources, increases boron content, reduces synthesis difficulty, and simplifies the process.
It enables safe, low-temperature synthesis of high-boron-content polymers, improves synthesis efficiency and purity, is suitable for mass production, and enhances the high-temperature thermal stability and antioxidant properties of polymers.
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Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of high polymer materials, in particular to a high-boron-content polymer and a preparation method and application thereof. BACKGROUND
[0002] Currently, boron-containing polymers are mainly prepared by using borane chlorosilane, borane dimethyl sulfide and boron trichloride to provide boron source, and then through multiple high-temperature and long-time reactions to prepare the boron-containing polymers. The disadvantages of this method are as follows: on the one hand, the boron content of the boron source reactant is too low, and an excessive amount of the boron source reactant needs to be added to increase the boron content in the polymer, which increases the inorganic elements such as chlorine and sulfur in the reactant, thereby reducing the purity of the polymer and making it difficult to mass-produce; on the other hand, the boron source reactant containing inorganic elements has a certain toxicity; and on the other hand, the polymer needs to be synthesized through multiple high-temperature and long-time reactions, which increases the difficulty of synthesizing the boron-containing polymer and reduces the synthesis efficiency. SUMMARY
[0003] The present application solves the problems of toxicity of the boron source reactant, low boron content of the boron source reactant and great synthesis difficulty in the process of preparing the boron-containing polymer.
[0004] To solve the above problems, the present application provides a high-boron-content polymer and a preparation method and application thereof.
[0005] In a first aspect, the present application provides a preparation method of a high-boron-content polymer, which comprises the following steps:
[0006] S1: dissolving polysilazane in an organic solvent under the protection of nitrogen or argon to obtain a polysilazane mixed solution;
[0007] S2: adding ammonia borane to the polysilazane mixed solution at a temperature of-10℃ to 0℃ and stirring to react, to obtain a high-boron-content polymer.
[0008] Optionally, step S2 specifically comprises: adding ammonia borane to the polysilazane mixed solution, stirring to react at a temperature of-10℃ to 0℃, and performing vacuum distillation on the reacted solution to remove the organic solvent and impurities, to obtain the high-boron-content polymer.
[0009] Optionally, the reacted solution is subjected to vacuum distillation in a rotating state.
[0010] Optionally, the organic solvent comprises toluene and / or acetone.
[0011] Optionally, the concentration of the polysilazane in the polysilazane mixed solution is 10-30wt%.
[0012] Optionally, the mass ratio of the added polysilazane to ammonia borane is (5-1):1.
[0013] Optionally, the reaction is stirred at a temperature of -10℃ to 0℃ for 1-3h in step S2.
[0014] In a second aspect, the present application provides a high-boron-content polymer prepared by the method for preparing a high-boron-content polymer according to any one of the above.
[0015] Optionally, the high-boron-content polymer has a boron content of more than 20wt%.
[0016] In a third aspect, the present application provides use of the high-boron-content polymer according to the above in the field of preparing organic precursor polymer-derived ceramics.
[0017] The high-boron-content polymer, the method for preparing the same and the use thereof have the following beneficial effects: the polysilazane is dissolved in an organic solvent, and the boron hydride reaction between ammonia borane and the polysilazane occurs at a temperature of -10℃ to 0℃ through low-temperature liquid-phase assistance, so that the high-boron-content polymer is prepared; the use of ammonia borane as the boron source avoids the influence of inorganic elements such as chlorine and sulfur in traditional boron sources (e.g., borane chlorosilane, borane dimethyl sulfide and boron trichloride), reduces the synthesis difficulty and increases the synthesis efficiency; and compared with the boron source for preparing a traditional polymer, ammonia borane has a higher boron content and is non-toxic and safe; at the same time, the synthesis can be completed under low-temperature conditions, avoiding the high-temperature, long-time and complex synthesis process of traditional polymer preparation, so that the reaction is easier and safer, the synthesis efficiency of the synthesized polymer is improved, and the high-boron-content polymer can be generated in large quantities. BRIEF DESCRIPTION OF DRAWINGS
[0018] Figure 1 A flowchart of the method for preparing the high-boron-content polymer of the embodiment of the present application;
[0019] Figure 2 X-ray photoelectron spectroscopy of the high-boron-content polymer of Example 1 of the present application;
[0020] Figure 3 Infrared spectrogram of the high-boron-content polymer of Example 1 of the present application;
[0021] Figure 4 Thermogravimetric curve of the high-boron-content polymer of Example 1 of the present application. DETAILED DESCRIPTION
[0022] In order to make the above objectives, characteristics and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application are described in detail below with reference to the drawings. Although some embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms, and should not be interpreted as being limited to the embodiments described herein, on the contrary, these embodiments are provided for a more thorough and complete understanding of the present application. It should be understood that the drawings and embodiments of the present application are only for exemplary purposes, and are not intended to limit the scope of protection of the present application.
[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application;
[0024] The term "comprising" and variations thereof as used herein are open-ended, that is "including but not limited to"; the term "based on" is "based, at least in part, on"; the term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments"; the term "optional" means "optional in at least some embodiments". Related definitions are given throughout the detailed description. It is to be noted that the concepts "first", "second", etc. mentioned in the present application are used to distinguish different objects, and are not used to describe a specific order or primary and secondary relationship. In addition, the terms "first", "second" are only for description purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include one or more features. In the description of the present application, unless otherwise stated, the meaning of "a plurality of" is two or more.
[0025] In the related art, a very effective way to produce high-performance ceramics (SiC / Si3N4 / SiBCN) is to prepare it by the organic precursor polymer-derived ceramic (PDC) method, which can provide a uniform and controllable chemical composition for high-purity ceramic materials at the molecular scale. Therefore, the regulation of PDC ceramic structure and function can be realized based on the design of the types and contents of elements in the polymer, and the molecular structure with high boron content helps to improve the high-temperature thermal stability and high-temperature oxidation resistance of PDC ceramics, so as to further apply and expand them in the field of high-temperature ablation resistance in aerospace and other fields, and high boron content can improve the high-temperature carbon residue rate of the polymer and the ceramic yield. Therefore, high-boron-content polymers have attracted widespread attention from the scientific research community and the industry.
[0026] In the prior art, boron sources such as borane chlorosilane, borane dimethyl sulfide and boron trichloride are provided, and a polymer containing boron is finally prepared through multi-step reactions with other small molecules containing silicon elements, carbon elements and nitrogen elements. However, the boron content in the traditional boron source (borane chlorosilane, borane dimethyl sulfide and boron trichloride) is low, resulting in a low boron content in the finally synthesized polymer, and the boron content is generally less than 10wt%. In addition, the branched chain in the traditional boron source contains a large amount of inorganic elements such as chlorine and sulfur, which not only reduces the reactivity and requires to increase the reaction temperature to ensure the synthesis of the polymer, but also needs to be synthesized through multiple reactions at different temperatures and purified multiple times to avoid introducing inorganic elements into the finally synthesized polymer.
[0027] To solve the problems in the above related technologies, the present embodiment provides a high-boron-content polymer and a preparation method and application thereof.
[0028] As shown in Figure 1 The present embodiment provides a preparation method of a high-boron-content polymer, which comprises the following steps:
[0029] S1: dissolving polysilazane in an organic solvent under nitrogen or argon protection to obtain a polysilazane mixed solution;
[0030] S2: adding ammonia borane to the polysilazane mixed solution at a temperature of-10℃ to 0℃ and stirring to react to obtain a high-boron-content polymer.
[0031] In the present embodiment, polysilazane is dissolved in an organic solvent, and ammonia borane with high boron content is used as a boron source. At a temperature of-10℃ to 0℃, the boron hydrogen reaction between ammonia borane and polysilazane is assisted by low-temperature liquid phase to prepare a high-boron-content polymer. Using ammonia borane as a boron source avoids the influence of inorganic elements such as chlorine and sulfur in the traditional boron source (e.g. borane chlorosilane, borane dimethyl sulfide and boron trichloride), reduces the synthesis difficulty and increases the synthesis efficiency. Compared with the traditional boron source for synthesizing polymers, ammonia borane has a higher boron content and is non-toxic and safe. At the same time, the synthesis can be completed under low-temperature conditions, avoiding the high-temperature and long-time complex synthesis process in the traditional preparation of polymers, and the reaction is easier and safer, thereby improving the synthesis efficiency of the synthesized polymer.
[0032] Specifically, ammonia borane is added dropwise to the polysilazane mixed solution to uniformly disperse the ammonia borane in the mixed solution, thereby improving the reaction efficiency.
[0033] In this embodiment, the polysilazane and ammonia borane are reacted at a temperature of -10 to 0°C. Ammonia borane will polymerize when heated. After heating, the molecular structure of ammonia borane changes and reorganizes, and the intermolecular interaction first polymerizes into (NH2BH2)n. If heating continues, it will continue to polymerize into (NHBH)n, which will cause waste of ammonia borane, and heating will also cause waste of energy. If the reaction temperature is too low, below -10°C, the reaction will be difficult and slow.
[0034] Optionally, step S2 specifically comprises: adding ammonia borane into the polysilazane mixed solution, stirring and reacting at a temperature of -10 to 0°C, and removing the organic solvent and impurities from the reacted solution by vacuum distillation to obtain the high-boron-content polymer.
[0035] In this optional embodiment, the impurities, organic solvents and by-products in the high-boron-content polymer can be removed.
[0036] Optionally, the reacted solution is subjected to vacuum distillation in a rotating state.
[0037] In this optional embodiment, the vacuum distillation is performed by using the rotating method, which is simple to operate.
[0038] Optionally, the organic solvent comprises toluene and / or acetone.
[0039] Specifically, in the process of adding the polysilazane into the organic solvent, the polysilazane needs to be slowly added into the organic solvent and ultrasonically dispersed to configure a mixed solution in which the polysilazane is uniformly dissolved in the organic solvent.
[0040] Optionally, the concentration of the polysilazane in the polysilazane mixed solution is 10-30wt%.
[0041] In this optional embodiment, when the concentration of the polysilazane is low, for example, lower than 10wt%, the synthesis efficiency and synthesis amount of the boron-containing polymer will be reduced due to the low concentration of the reactant. When the concentration of the polysilazane is high, for example, higher than 30wt%, the viscosity of the solution will be high, which will make it difficult for the polysilazane to be completely dissolved in the organic solvent and cause the agglomeration phenomenon.
[0042] Optionally, the mass ratio of the added polysilazane to ammonia borane is (5-1):1.
[0043] In this optional embodiment, by changing the ratio of the polysilazane to ammonia borane, the type and content of the boron-containing polymer can be adjusted. When the mass ratio of the polysilazane to ammonia borane is (5-1):1, the ratio is appropriate, which can improve the synthesis efficiency of the high-boron-content polymer and increase the boron content of the high-boron-content polymer.
[0044] Optionally, the step S2 is stirred at a temperature of -10℃ to 0℃ for 1-3h.
[0045] In this optional embodiment, the synthesis reaction can be completed in a short time, avoiding the long and complex synthesis process of traditional polymer preparation, and improving the synthesis efficiency of the synthesized polymer.
[0046] The high-boron-content polymer provided by the embodiment of the present application is prepared by using the preparation method of the high-boron-content polymer according to any one of the above.
[0047] In this embodiment, the high-boron-content polymer has a high content of boron element and good stability.
[0048] Optionally, the content of boron element in the high-boron-content polymer is higher than 20wt%.
[0049] In this optional embodiment, the high-boron-content polymer has a high content of boron element and good stability.
[0050] The high-boron-content polymer provided by the embodiment of the present application is prepared by using the preparation method of the high-boron-content polymer according to any one of the above.
[0051] In this embodiment, the high-boron-content polymer has a high content of boron element and good stability.
[0052] The present application will be further described in combination with specific embodiments.
[0053] Embodiment 1, preparation of high-boron-content polymer
[0054] Firstly, 20g of polysilazane is placed in a glove box filled with nitrogen for 1h, and then slowly added into 80g of toluene organic solvent, and the polysilazane is completely dissolved in the toluene organic solvent by ultrasonic oscillation to prepare a mixed solution with a polysilazane concentration of 20wt%.
[0055] Secondly, ammonia borane is slowly added into the mixed solution prepared in the first step, and the mass ratio of polysilazane to ammonia borane is 2:1, and the mixed reaction solution with appropriate viscosity is obtained by stirring in a blender.
[0056] Thirdly, the mixed reaction solution in the second step is subjected to low-temperature reaction: the reaction time is 1h and the reaction temperature is 0℃.
[0057] Fourthly, the mixed solution after reaction in the third step is subjected to reduced pressure distillation, including: the mixed solution is subjected to reduced pressure distillation in a rotating state to obtain a high-boron-content polymer.
[0058] like Figure 2 As shown, the composition of the obtained high-boron-content polymer was analyzed using X-ray diffraction, such as... Figure 3 As shown, infrared spectroscopy was used to analyze and identify the molecules of the obtained high-boron-content polymer. Figure 2 and Figure 3 As shown, the high boron content polymer prepared in this embodiment contains five elements: silicon, boron, carbon, nitrogen, and hydrogen, and is an organic polymer with BN-Si-C as the main chain and -CH3 as the branch chain.
[0059] like Figure 4 As shown, the thermogravimetric analysis (DSC) method was used to analyze the thermogravimetric curve of the high boron content polymer obtained in Example 1. Figure 4 It is evident that polymers with high boron content exhibit high stability and yield, which is beneficial for preparing PCD ceramics with excellent high-temperature performance.
[0060] Example 2, Preparation of high boron content polymer
[0061] The first step is to let 20g of polysilazane stand in an argon-filled glove box for 1 hour, then slowly add it to 80g of acetone organic solvent. The polysilazane is then completely dissolved in toluene organic solvent by ultrasonic vibration to prepare a mixed solution with a polysilazane concentration of 20wt%.
[0062] The second step involves slowly adding ammonia borane to the mixed solution prepared in the first step. The mass ratio of polysilazane to ammonia borane is 2:1. The mixture is stirred evenly in a mixer to obtain a mixed reaction solution with a suitable viscosity.
[0063] The third step involves subjecting the mixed reaction solution from the second step to a low-temperature reaction: the reaction time is 2 hours and the reaction temperature is 0°C.
[0064] The fourth step, performing vacuum distillation on the mixed solution after the reaction in the third step, includes: performing vacuum distillation on the mixed solution under a rotating state to obtain a polymer with high boron content.
[0065] Example 3, Preparation of high boron content polymer
[0066] The first step is to let 10g of polysilazane stand in an argon-filled glove box for 1 hour, then slowly add it to 90g of toluene organic solvent. The polysilazane is then completely dissolved in the toluene organic solvent by ultrasonic vibration to prepare a mixed solution with a polysilazane concentration of 10wt%.
[0067] Second step, slowly add ammonia borane into the mixed solution prepared in the first step, the mass ratio of polysilazane to ammonia borane is 2:1, stir uniformly in the blender, and obtain a mixed reaction solution with appropriate viscosity.
[0068] Third step, carry out low-temperature reaction on the mixed reaction solution in the second step: reaction time is 3h and reaction temperature is 0℃.
[0069] Fourth step, carry out reduced pressure distillation on the mixed solution after reaction in the third step, including: carry out reduced pressure distillation on the mixed solution in a rotating state, and obtain a polymer with high boron content.
[0070] Example 4, preparation of a polymer with high boron content
[0071] First step, after 30g of polysilazane is placed in an argon-filled glove box for 1 hour, slowly add it into 70g of toluene organic solvent, completely dissolve the polysilazane in the toluene organic solvent by means of ultrasonic oscillation, and prepare a mixed solution with polysilazane concentration of 30wt%.
[0072] Second step, slowly add ammonia borane into the mixed solution prepared in the first step, the mass ratio of polysilazane to ammonia borane is 5:1, stir uniformly in the blender, and obtain a mixed reaction solution with appropriate viscosity.
[0073] Third step, carry out low-temperature reaction on the mixed reaction solution in the second step: reaction time is 1h and reaction temperature is -5℃.
[0074] Fourth step, carry out reduced pressure distillation on the mixed solution after reaction in the third step, including: carry out reduced pressure distillation on the mixed solution in a rotating state, and obtain a polymer with high boron content.
[0075] Example 5, preparation of a polymer with high boron content
[0076] First step, after 20g of polysilazane is placed in an argon-filled glove box for 1 hour, slowly add it into 80g of toluene organic solvent, completely dissolve the polysilazane in the toluene organic solvent by means of ultrasonic oscillation, and prepare a mixed solution with polysilazane concentration of 20wt%.
[0077] Second step, slowly add ammonia borane into the mixed solution prepared in the first step, the mass ratio of polysilazane to ammonia borane is 1:1, stir uniformly in the blender, and obtain a mixed reaction solution with appropriate viscosity.
[0078] Third step, carry out low-temperature reaction on the mixed reaction solution in the second step: reaction time is 1h and reaction temperature is -10℃.
[0079] In the fourth step, the mixed solution after the reaction in the third step is subjected to reduced pressure distillation, including: subjecting the mixed solution to reduced pressure distillation in a rotating state to obtain the high-boron-content polymer.
[0080] The results of Examples 2-5 are the same as those of Example 1, and the prepared high-boron-content polymers all have five elements of silicon, boron, carbon, nitrogen and hydrogen, and are organic polymers with a B-N-Si-C main chain and -CH3 side chains. The high-boron-content polymers obtained in Examples 2-5 also have high stability and yield, and are conducive to the preparation of PCD ceramics with excellent high-temperature performance.
[0081] Although the present application is disclosed as above, the scope of protection of the present application is not limited to this. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application, and these changes and modifications will fall within the scope of protection of the present application.
Claims
1. A method for preparing a high boron content polymer, characterized by, The method comprises the following steps: S1: dissolving polysilazane in an organic solvent under nitrogen or argon protection to obtain a polysilazane mixed solution; S2: adding ammonia borane to the polysilazane mixed solution at a temperature of -10 to 0 ℃, and stirring to react to obtain a high-boron-content polymer, wherein the content of boron in the high-boron-content polymer is higher than 20 wt%.
2. The method for preparing the high boron content polymer according to claim 1, characterized in that, The step S2 specifically comprises: adding ammonia borane to the polysilazane mixed solution, stirring to react at a temperature of -10 to 0 ℃, and performing vacuum distillation on the reacted solution to remove the organic solvent and impurities to obtain the high-boron-content polymer.
3. The method for preparing the high boron content polymer according to claim 2, characterized in that, The reacted solution is subjected to vacuum distillation in a rotating state.
4. The method for preparing the high boron content polymer according to claim 1, characterized in that, The organic solvent comprises toluene and / or acetone.
5. The method for preparing the high boron content polymer according to claim 1, characterized in that, The concentration of the polysilazane in the polysilazane mixed solution is 10-30 wt%.
6. The method for preparing the high boron content polymer according to claim 1, characterized in that, The mass ratio of the polysilazane to the ammonia borane is (5-1):
1.
7. The method for preparing the high boron content polymer according to claim 1, characterized in that, The stirring to react in the step S2 is performed at a temperature of -10 to 0 ℃ for 1-3 h.
8. A high boron content polymer characterized by, The high-boron-content polymer is prepared by using the preparation method of any one of claims 1-7.
9. The high boron content polymer of claim 8, wherein, The content of boron in the high-boron-content polymer is higher than 20 wt%.
10. Use of the high-boron-content polymer of claim 8 or 9 in the field of preparing organic precursor polymer-derived ceramics.
Citation Information
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