Aerogel compounded rubber thermal barrier material based on electrostatic flocking technology and preparation method of aerogel compounded rubber thermal barrier material

Abstract

The invention relates to the technical field of thermal barrier materials, and discloses an aerogel composite rubber thermal barrier material based on an electrostatic flocking technology and a preparation method thereof, and the preparation method comprises the steps of aerogel particle surface treatment, electrostatic flocking, hot-pressing crosslinking, cooling shaping and the like. The aerogel particles are vertically implanted into the surface of a rubber matrix through an electrostatic flocking technology, so that the interface bonding force and the mechanical strength are remarkably enhanced, meanwhile, the high porosity characteristic of aerogel is reserved, and the thermal barrier property is improved. A coupling agent is preferably selected for modification to improve compatibility, and hot pressing parameters are optimized to ensure stable performance. The problems that traditional aerogel is prone to fragmentation and weak in interface bonding are solved, and the aerogel is suitable for the high-temperature and high-pressure complex environment and has excellent comprehensive performance and practical value.

Description

Technical Field

[0001] This invention relates to the field of thermal barrier materials technology, specifically to an aerogel composite rubber thermal barrier material based on electrostatic flocking technology and its preparation method. Background Technology

[0002] Aerogels, as materials with extremely low density and high porosity, have shown broad application prospects in fields such as thermal insulation, sound insulation, and adsorption. However, traditional aerogels suffer from problems such as low mechanical strength and fragility in practical applications. For example, in thermal barrier scenarios requiring the withstand of certain external forces or complex environmental conditions, the structural stability of traditional aerogels is insufficient; when combined with flexible materials, their overall performance often fails to meet the application requirements. To improve these problems and enhance the comprehensive performance of aerogels, researchers have gradually turned their attention to the development of composite materials. Summary of the Invention

[0003] This invention provides an aerogel composite rubber thermal barrier material based on electrostatic flocking technology and its preparation method, which solves the problems of insufficient mechanical strength, fragility, and difficulty in meeting the overall performance requirements of complex environments when combined with flexible materials. At the same time, it proposes an improvement scheme to address the problems of insufficient thermal stability and weak interfacial bonding of existing thermal barrier materials under high temperature and high pressure environments.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing an aerogel composite rubber thermal barrier material based on electrostatic flocking technology, comprising the following steps: Surface treatment of aerogel particles; The treated aerogel particles are mixed with a rubber matrix, which includes, but is not limited to, one or more of natural rubber, styrene-butadiene rubber, silicone rubber or fluororubber; The mixed material is placed in an electrostatic field for flocking treatment. The applied voltage range during the flocking process is 10-30kV, and the flocking time is 5-20 minutes. The flocked material is hot-pressed, with the hot-pressing temperature controlled at 120℃-180℃, the pressure range at 5-15MPa, and the time at 10-30 minutes. The material, after being hot-pressed and cooled to room temperature, yields an aerogel composite rubber thermal barrier material.

[0005] Preferably, when the rubber matrix comprises silicone rubber and fluororubber, the mass ratio is (3-5):(1-2); the hot pressing temperature is 140℃-160℃, the pressure is 8-12MPa, and the time is 15-25 minutes.

[0006] Preferably, a method for preparing an aerogel composite rubber thermal barrier material based on electrostatic flocking technology further includes the following steps: Aerogel particle pretreatment: Crush the aerogel particles to 50-200 mesh, then soak them in a 1%-5% sodium hydroxide solution for 1-3 hours. The liquid-to-solid ratio during soaking is (8-15):1 (mL / g). After filtration, wash with deionized water until neutral, and dry at 80-100℃ for 2-4 hours for later use. Surface modification: The pretreated aerogel particles are added to a coupling agent solution with a mass fraction of 0.5%-2%. The coupling agent includes, but is not limited to, one of silane coupling agents, titanate coupling agents or aluminate coupling agents. The stirring speed is 100-300 r / min, the reaction time is 1-3 hours, and then the mixture is filtered and dried. Rubber matrix plasticization: The selected rubber matrix raw materials are mixed in proportion and plasticized on a two-roll mill at a temperature of 60℃-90℃ for 5-15 minutes to obtain a uniform rubber matrix. Electrostatic flocking: Surface-modified aerogel particles are evenly spread on the surface of a rubber substrate and placed in an electrostatic field. By adjusting the electrode spacing to 10-30cm and the voltage to 10-30kV, the aerogel particles are vertically implanted into the surface of the rubber substrate under the action of electrostatics, forming a stable flocking structure. Hot-press crosslinking: The flocked material is placed in a hot press for crosslinking treatment. The hot pressing temperature is 120℃-180℃, the pressure is 5-15MPa, and the time is 10-30 minutes to promote the interfacial bonding between the rubber matrix and the aerogel particles. Cooling and shaping: The hot-pressed cross-linked material is naturally cooled to room temperature, and then cut or trimmed to obtain the final aerogel composite rubber heat barrier material.

[0007] Preferably, an aerogel composite rubber thermal barrier material based on electrostatic flocking technology is prepared by the above-described preparation method.

[0008] Preferably, an aerogel composite rubber thermal barrier material based on electrostatic flocking technology comprises, by weight, the following raw materials: 30-50 parts aerogel particles, 40-60 parts rubber matrix, and 2-8 parts coupling agent; wherein the aerogel particles are one or more of silica aerogel, carbon aerogel, or alumina aerogel.

[0009] This invention employs electrostatic flocking technology to vertically implant aerogel particles onto the surface of a rubber matrix, forming a unique flocked structure. This structure not only significantly enhances the interfacial bonding between the aerogel particles and the rubber matrix but also effectively improves the overall mechanical strength and impact resistance of the material. Furthermore, the high porosity of the aerogel particles is preserved, thus endowing the material with excellent thermal barrier properties. Under high temperature and high pressure environments, the material exhibits good thermal stability and durability, enabling it to meet the demands of complex operating conditions.

[0010] In this invention, the introduction of a coupling agent further improves the compatibility between aerogel particles and the rubber matrix, avoiding delamination or peeling caused by insufficient interfacial bonding. The temperature and pressure parameters during the hot-press crosslinking process are optimized to ensure sufficient crosslinking between the rubber matrix and the aerogel particles, while preventing structural damage to the aerogel particles due to excessive temperature or pressure. The cooling and setting step ensures the dimensional stability and smoothness of the material.

[0011] In summary, this invention, by combining electrostatic flocking technology with hot-press cross-linking process, successfully solves the shortcomings of traditional aerogels in terms of mechanical strength and interfacial bonding, while improving the thermal barrier properties and overall performance of the material, demonstrating significant technological advancement and practical value. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the process flow for surface modification treatment of aerogel particles according to the present invention; Figure 2 This is a schematic diagram of the structural frame of the electrostatic flocking process of the present invention; Figure 3 This is a schematic diagram of the working state of the hot pressing molding equipment of the present invention. Detailed Implementation

[0013] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0014] This invention provides an aerogel composite rubber thermal barrier material based on electrostatic flocking technology and its preparation method, the specific implementation of which is described in detail with reference to the accompanying drawings. The following content will describe the selection of materials, the refinement of process steps, and the connection and fit relationships between various components.

[0015] exist Figure 1The diagram illustrates the process flow for surface modification of aerogel particles. First, aerogel particles are selected as the main raw material; the material can be one or more of silica aerogel, carbon aerogel, or alumina aerogel. After preliminary pulverization, the particle size is controlled between 50-200 mesh. Then, they are immersed in a 1%-5% sodium hydroxide solution with a liquid-to-solid ratio of (8-15):1 (mL / g) for 1-3 hours. The main purpose of this step is to remove impurities from the surface of the aerogel particles and roughen their surface to improve the subsequent reaction efficiency with the coupling agent. After immersion, the aerogel particles are washed multiple times with deionized water until the solution is neutral, and then dried at 80-100℃ for 2-4 hours. The dried aerogel particles then proceed to the next surface modification treatment, specifically by adding the aerogel particles to a 0.5%-2% coupling agent solution and stirring at a speed of 100-300 r / min for 1-3 hours. The coupling agent can be one of silane coupling agents, titanate coupling agents, or aluminate coupling agents. After stirring, the aerogel particles are filtered and dried to form a uniform coupling agent coating layer on their surface. This process enhances the interfacial bonding between the aerogel particles and the rubber matrix through the action of the coupling agent.

[0016] exist Figure 2 The diagram illustrates the structural framework of the electrostatic flocking process. Surface-modified aerogel particles are uniformly spread onto the surface of a rubber matrix. The rubber matrix material includes, but is not limited to, one or more of natural rubber, styrene-butadiene rubber, silicone rubber, or fluororubber, and when the rubber matrix contains silicone rubber and fluororubber, their mass ratio is (3-5):(1-2). The rubber matrix is ​​plasticized on a two-roll mill to form a uniform sheet structure at a temperature of 60℃-90℃ for 5-15 minutes. Subsequently, the rubber matrix is ​​placed in an electrostatic field formed by electrostatic electrodes with a spacing of 10-30 cm and an applied voltage range of 10-30 kV for 5-20 minutes. During this process, the aerogel particles are vertically implanted into the surface of the rubber matrix under the action of the electrostatic field, forming a stable flocked structure. Due to the effect of the electrostatic field, the aerogel particles can be embedded into the rubber matrix with a high density and vertical orientation, thereby significantly enhancing the interfacial bonding force between the two.

[0017] Figure 3A schematic diagram of the hot press molding equipment's operation is shown. The flocked material is placed between the upper and lower molds of the hot press for hot pressing cross-linking. The upper and lower molds apply pressure to the material, ranging from 5-15 MPa, with the hot pressing temperature controlled at 120℃-180℃ for 10-30 minutes. When the rubber matrix contains silicone rubber and fluororubber, the preferred hot pressing temperature is 140℃-160℃, the pressure is 8-12 MPa, and the time is 15-25 minutes. During hot pressing, an interfacial bonding layer gradually forms between the rubber matrix and the aerogel particles. The thickness and strength of this interfacial bonding layer are significantly affected by the hot pressing parameters. By optimizing the hot pressing temperature and pressure, sufficient cross-linking between the rubber matrix and the aerogel particles is ensured, while structural damage to the aerogel particles due to excessive temperature or pressure is avoided. During the hot pressing process, the design of the upper and lower molds of the hot press ensures that the material is subjected to uniform stress. Temperature and pressure sensors monitor the temperature and pressure distribution in real time during the hot pressing process to ensure precise control of process parameters.

[0018] Aerogel particles are vertically embedded in the rubber matrix, forming a stable interfacial bonding layer. The presence of this layer significantly improves the overall mechanical strength and impact resistance of the material, while retaining the high porosity of the aerogel particles, thus endowing the material with excellent thermal barrier properties. Under high temperature and high pressure environments, the material exhibits good thermal stability and durability, enabling it to meet the demands of complex operating conditions.

[0019] The cooling and shaping process ensures the appearance quality and dimensional accuracy of the material. The cooling process adopts natural cooling to room temperature to avoid stress concentration caused by rapid cooling, which would affect the material performance.

[0020] The test sample exhibited excellent thermal stability under high temperature and high pressure conditions. Test data recorded by temperature and pressure sensors showed that the material's performance degradation was small under extreme conditions, resulting in a long service life.

[0021] In practical applications, this aerogel composite rubber thermal barrier material can be used in aerospace, automotive industry, and building insulation. For example, in aerospace, this material can be used to manufacture thermal insulation layers on spacecraft surfaces, effectively blocking the impact of external high temperatures on internal equipment; in the automotive industry, this material can be used for thermal insulation protection of engine compartments, improving vehicle safety and comfort; in building insulation, this material can be used in the preparation of wall insulation layers, reducing building energy consumption. Through the detailed description of the above specific embodiments, those skilled in the art can fully implement this technical solution according to the contents of the specification, ensuring the feasibility and practicality of the technical solution.

[0022] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing an aerogel composite rubber thermal barrier material based on electrostatic flocking technology, characterized in that, Includes the following steps: Surface treatment of aerogel particles; The treated aerogel particles are mixed with a rubber matrix, wherein the rubber matrix includes one or more of natural rubber, styrene-butadiene rubber, silicone rubber or fluororubber; The mixed material is placed in an electrostatic field for flocking treatment. The voltage applied during the flocking process is 10kV-30kV, and the flocking time is 5 minutes-20 minutes. The flocked material is hot-pressed, with the hot-pressing temperature controlled at 120℃-180℃, the pressure range at 5MPa-15MPa, and the time at 10 minutes-30 minutes. The material after hot pressing is cooled to room temperature to obtain an aerogel composite rubber thermal barrier material.

2. The method for preparing an aerogel composite rubber thermal barrier material based on electrostatic flocking technology according to claim 1, characterized in that, When the rubber matrix contains silicone rubber and fluororubber, the mass ratio is (3-5):(1-2); the hot pressing temperature is 140℃-160℃, the pressure is 8MPa-12MPa, and the time is 15 minutes-25 minutes.

3. The method for preparing an aerogel composite rubber thermal barrier material based on electrostatic flocking technology according to claim 1, characterized in that, It also includes the following steps: Aerogel particle pretreatment: Crush the aerogel particles to 50-200 mesh, then soak them in a 1%-5% sodium hydroxide solution for 1-3 hours. The liquid-solid ratio during soaking is (8-15):1 (mL / g). After filtration, wash with deionized water until neutral, and dry at 80℃-100℃ for 2-4 hours for later use. Surface modification: The pretreated aerogel particles are added to a coupling agent solution with a mass fraction of 0.5%-2%, wherein the coupling agent includes one of silane coupling agent, titanate coupling agent or aluminate coupling agent, the stirring speed is 100r / min-300r / min, the reaction time is 1 hour-3 hours, and then filtered and dried. Rubber matrix plasticization: The selected rubber matrix raw materials are mixed in proportion and plasticized on a two-roll mill at a temperature of 60℃-90℃ for 5-15 minutes to obtain a uniform rubber matrix.

4. The method for preparing an aerogel composite rubber thermal barrier material based on electrostatic flocking technology according to claim 3, characterized in that, The electrostatic flocking process involves uniformly spreading surface-modified aerogel particles onto the surface of a rubber substrate and placing them in an electrostatic field electrode. By adjusting the electrode spacing to 10cm-30cm and the voltage to 10kV-30kV, the aerogel particles are vertically implanted into the surface of the rubber substrate under electrostatic action, forming a stable flocking structure.

5. The method for preparing an aerogel composite rubber thermal barrier material based on electrostatic flocking technology according to claim 1, characterized in that, The hot pressing process includes placing the flocked material between the upper and lower molds of a hot press for cross-linking treatment. The hot pressing temperature is 120℃-180℃, the pressure is 5MPa-15MPa, and the time is 10 minutes-30 minutes, which promotes the formation of an interfacial bonding layer between the rubber matrix and the aerogel particles.

6. The method for preparing an aerogel composite rubber thermal barrier material based on electrostatic flocking technology according to claim 1, characterized in that, The cooling and shaping process includes naturally cooling the hot-pressed cross-linked material to room temperature, followed by cutting or trimming to obtain the final aerogel composite rubber thermal barrier material.

7. An aerogel composite rubber thermal barrier material based on electrostatic flocking technology, characterized in that: It is prepared by the preparation method according to any one of claims 1-6.

8. The aerogel composite rubber thermal barrier material based on electrostatic flocking technology according to claim 7, characterized in that, By weight, it includes the following raw materials: 30-50 parts aerogel particles, 40-60 parts rubber matrix, and 2-8 parts coupling agent; wherein the aerogel particles are one or more of silica aerogel, carbon aerogel, or alumina aerogel.

9. The aerogel composite rubber thermal barrier material based on electrostatic flocking technology according to claim 7, characterized in that, The aerogel particles are embedded vertically into the rubber matrix to form a stable interfacial bonding layer.

10. The aerogel composite rubber thermal barrier material based on electrostatic flocking technology according to claim 7, characterized in that, The thickness and strength of the interface bonding layer are affected by the hot pressing parameters: the hot pressing temperature is 120℃-180℃, the pressure is 5MPa-15MPa, and the time is 10 minutes-30 minutes.

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