Modified fiber filler for heat-resistant material, preparation method and application
By introducing double-bonded active groups into the fiber surface through chemical modification, the problem of poor interfacial bonding strength between silicone rubber-based ablation materials and fiber materials was solved, thereby improving the heat protection performance of aerospace vehicles.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- WUHAN UNIV
- Filing Date
- 2026-03-20
- Publication Date
- 2026-06-30
AI Technical Summary
Existing silicone rubber-based ablation materials have poor interfacial bonding strength with fiber materials, which makes the interface prone to debonding and cannot meet the high temperature and high pressure environment requirements of aerospace vehicles.
By chemically modifying the fiber surface, an organosilicon tackifier is used to introduce double-bonded active groups on the fiber surface, which react with liquid silicone rubber to improve the interfacial bonding strength.
It improves the interfacial bonding strength between fibers and silicone rubber, solves the problem of interfacial debonding, enhances the service performance of composite materials, and meets the flight requirements of aerospace vehicles.
Smart Images
Figure CN122302377A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of fiber-reinforced composite materials technology, and in particular to a modified fiber filler for heat-resistant materials, its preparation method, and its application. Background Technology
[0002] With the development of the aerospace industry, especially the increase in flight mileage, flight time, and flight speed of aerospace vehicles, more severe challenges have been brought to the main components of the aircraft. A large amount of aerodynamic heat is generated during the flight of the aircraft. Therefore, thermal protection of its surface and keeping its internal components below a reasonable temperature are the premise and foundation for the normal operation of the aircraft, as well as the basic guarantee for the service life and safety performance of the aircraft.
[0003] With the development of technology, silicone rubber-based ablation thermal protection materials have emerged for aerospace vehicles. Among them, standard density ablation materials, represented by fiber cloth or fiber fabric, are mainly used in long-range vehicles that operate for short periods of time in extremely harsh thermal environments such as high heat flux, ultra-high temperature, high stagnation pressure, and high-speed particle erosion. These standard density thermal protection materials can be prepared by casting high-performance liquid silicone rubber pre-impregnation material, curing it into component blanks in autoclaves or hydraulic reactors, and then machining them.
[0004] However, silicone rubber, especially addition-cured liquid silicone rubber, has low surface energy and poor wettability with fiber materials. During flight, its interface is prone to debonding, which greatly reduces the service performance of the composite material and cannot meet the flight requirements of modern aircraft. Summary of the Invention
[0005] The purpose of this invention is to provide a modified fiber filler for heat-resistant materials, its preparation method, and its application. By chemically modifying the fiber surface with an organosilicon tackifier, the fiber surface is endowed with double-bonded active groups, which can react with liquid silicone rubber during curing. The organosilicon tackifier acts as a bridge to improve the interfacial adhesion strength between the fiber material and the silicone rubber, avoiding the risk of debonding.
[0006] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for preparing modified fiber fillers for heat-resistant materials, comprising the following steps: The silicone tackifier was dispersed in an activated solvent and then diluted to obtain a diluted tackifier. The fiber material is immersed in the diluted thickener and modified to obtain modified fiber. The modified fiber is removed and dried to obtain the modified fiber filler.
[0007] In some possible implementations, the silicone tackifier is a silicone polymer containing one or more of vinyl, propylene, and other double bond groups.
[0008] In some possible implementations, the activating solvent is one or more of petroleum ether, methyl acetate, ethyl acetate, butyl acetate, toluene, xylene, and cyclohexane.
[0009] In some possible implementations, the fiber filler is one or more of quartz fiber, glass fiber, carbon fiber, aramid fiber, etc.
[0010] In some possible implementations, the silicone tackifier has a mass fraction of 1-5% in the diluted tackifier.
[0011] Preferably, the silicone tackifier is a silicone polymer containing propylene groups, which has excellent effects. In the diluted tackifier, the silicone tackifier has excellent effects when its mass fraction is 2%.
[0012] In some possible implementations, the mass ratio of the fiber material to the diluent is 100:(300~500).
[0013] In some possible implementations, the modification process specifically includes setting the modification temperature to 30℃~80℃ and the modification time to 1~12h.
[0014] In some possible implementations, the drying process specifically includes setting the drying temperature to 30°C~80°C and the drying time to 12~24h.
[0015] In a second aspect, the present invention provides a modified fiber filler for heat-resistant materials, which is prepared based on the preparation method described in any one of the first aspects.
[0016] Thirdly, the present invention also provides an application of modified fiber filler for heat-resistant materials, based on the modified fiber filler for heat-resistant materials described in the second aspect, wherein the modified fiber filler for heat-resistant materials is suitable for fiber-reinforced silicone rubber-based heat protection applications, thereby improving the interfacial bonding strength between the fiber material and the silicone rubber in heat-resistant materials.
[0017] This invention provides a modified fiber filler for heat-resistant materials, its preparation method, and its application. It utilizes a tackifier with bridging properties to modify the fiber material, improving the interfacial adhesion strength between the fiber and silicone rubber. The organosilicon tackifier can functionally modify the fiber material while maintaining its original structural characteristics, giving it a certain degree of reactivity and enhancing its interfacial adhesion to addition-type silicone rubber heat-resistant materials. This solves the problems of poor wettability of silicone rubber to fibers and easy debonding at the interface in existing technologies. It has high application value in the fiber-reinforced silicone rubber-based heat protection industry. Compared with existing technologies, this invention can better enhance the service performance of composite materials, meeting the flight requirements of modern aircraft. Furthermore, the preparation method of the modified fiber filler for heat-resistant materials in this invention is simple to operate and conducive to large-scale production and use. Attached Figure Description
[0018] Figure 1 Modified fiber filler in silicone rubber impregnation state; Figure 2 The surface state of the modified fiber filler after it has been pulled out of the silicone rubber; Figure 3 This is a schematic diagram of the fiber pull-out strength test. Detailed Implementation
[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0020] Example 1 This embodiment provides a modified fiber filler for heat-resistant materials, which is suitable for fiber-reinforced silicone rubber-based heat protection applications and improves the interfacial bonding strength between the fiber material and silicone rubber in heat-resistant materials.
[0021] The preparation method of modified fiber filler for heat-resistant materials includes the following steps: 5g of vinyl silicone tackifier was dispersed in 300g of petroleum ether and diluted to obtain diluted tackifier; 100g of quartz fiber was soaked in a diluted tackifier for modification treatment. The modification temperature was set at 60℃ and the modification time was 2h to obtain modified fiber. The modified fibers were removed and dried at 80℃ for 12 hours to obtain the modified fiber filler. The modified fiber filler was then immersed in liquid silicone rubber and cured at 60℃ for 12 hours. The bond strength was then tested.
[0022] In other embodiments, the activating solvent may be one or more of methyl acetate, ethyl acetate, xylene, and cyclohexane; the fiber filler may be aramid fiber.
[0023] Example 2 This embodiment provides a modified fiber filler for heat-resistant materials, and the preparation method includes the following steps: 5g of vinyl silicone tackifier was dispersed in 500g of butyl acetate and diluted to obtain diluted tackifier; 100g of glass fiber was soaked in a diluted tackifier and modified. The modification temperature was set at 80℃ and the modification time was 1h to obtain modified fiber. The modified fibers were removed and dried at 60℃ for 24 hours to obtain the modified fiber filler. The modified fiber filler was then immersed in liquid silicone rubber and cured at 60℃ for 12 hours. The bond strength was then tested.
[0024] Example 3 This embodiment provides a modified fiber filler for heat-resistant materials, and the preparation method includes the following steps: 5g of propylene-based silicone tackifier was dispersed in 300g of toluene and diluted to obtain diluted tackifier; 100g of carbon fiber was soaked in a diluted tackifier and modified. The modification temperature was set at 50℃ and the modification time was 5h to obtain modified fiber. The modified fibers were removed and dried at 30°C for 24 hours to obtain the modified fiber filler. The modified fiber filler was then immersed in liquid silicone rubber and cured at 60°C for 12 hours. The bond strength was then tested.
[0025] Comparative Example 1 The only difference between this comparative example and Example 1 is that the quartz fiber is not modified. Instead, the quartz fiber is directly immersed in liquid silicone rubber and cured at 60°C for 12 hours. The bonding strength is then tested.
[0026] Comparative Example 2 The only difference between this comparative example and Example 2 is that the glass fiber is not modified; instead, it is directly immersed in liquid silicone rubber, cured at 60°C for 12 hours, and the bonding strength is tested.
[0027] Comparative Example 3 The only difference between this comparative example and Example 3 is that the carbon fiber is not modified. Instead, the carbon fiber is directly immersed in liquid silicone rubber, cured at 60°C for 12 hours, and the bonding strength is tested.
[0028] The adhesive strength of the samples prepared in Examples 1-3 and Comparative Examples 1-3 was determined according to GB / T532, and the test method is as follows: Figure 3 As shown, the specific results are shown in Table 1. The modified fiber filler in the silicone rubber impregnation state is as follows... Figure 1 As shown, the surface state of the modified fiber filler after being pulled out of the silicone rubber is as follows. Figure 2 As shown.
[0029] Table 1 The test results of Examples 1-3 and Comparative Examples 1-3 show that the interfacial bonding strength between the modified fiber and the liquid silicone rubber is significantly improved. From the perspective of the interface debonding mode, the debonding of the modified fiber group is all due to the destruction of the silicone rubber body, which shows that it has good interfacial bonding characteristics.
[0030] Obviously, those skilled in the art can make various modifications and variations to the embodiments of the present invention without departing from the spirit and scope of the invention. Therefore, if these modifications and variations fall within the scope of the claims of the present invention and their equivalents, the present invention also intends to include these modifications and variations.
Claims
1. A method for preparing modified fiber filler for heat-resistant materials, characterized in that, Includes the following steps: The silicone tackifier was dispersed in an activated solvent and then diluted to obtain a diluted tackifier. The fiber material is immersed in the diluted thickener and modified to obtain modified fiber. The modified fiber is removed and dried to obtain the modified fiber filler.
2. The method for preparing modified fiber filler for heat-resistant materials according to claim 1, characterized in that, The organosilicon tackifier is an organosilicon polymer containing one or more of vinyl, propylene, and other double bond groups.
3. The method for preparing modified fiber filler for heat-resistant materials according to claim 1, characterized in that, The activating solvent is one or more of petroleum ether, methyl acetate, ethyl acetate, butyl acetate, toluene, xylene, and cyclohexane.
4. The method for preparing modified fiber filler for heat-resistant materials according to claim 1, characterized in that, The fiber filler is one or more of the following: quartz fiber, glass fiber, carbon fiber, aramid fiber, etc.
5. The method for preparing modified fiber filler for heat-resistant materials according to claim 1, characterized in that, The mass ratio of the fiber material to the diluting tackifier is 100:(300~500).
6. The method for preparing modified fiber filler for heat-resistant materials according to claim 1, characterized in that, The modification process specifically includes setting the modification temperature to 30℃~80℃ and the modification time to 1~12h.
7. The method for preparing modified fiber filler for heat-resistant materials according to claim 1, characterized in that, In the diluted tackifier, the mass fraction of the organosilicon tackifier is 1-5%.
8. The method for preparing modified fiber filler for heat-resistant materials according to claim 1, characterized in that, The drying process specifically includes setting the drying temperature to 30℃~80℃ and the drying time to 12~24h.
9. A modified fiber filler for heat-resistant materials, characterized in that, Prepared according to the preparation method described in any one of claims 1-6.
10. An application of a modified fiber filler for heat-resistant materials, based on the modified fiber filler for heat-resistant materials according to claim 7, characterized in that, The modified fiber filler for the heat protection material is suitable for fiber-reinforced silicone rubber-based heat protection applications, and improves the interfacial bonding strength between the fiber material and the silicone rubber in the heat protection material.