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CN-118184380-B - Modified carbon fiber hard felt and preparation method and application thereof

CN118184380BCN 118184380 BCN118184380 BCN 118184380BCN-118184380-B

Abstract

The invention provides a modified carbon fiber hard felt, and a preparation method and application thereof. The modified carbon fiber hard felt comprises carbon fibers, and silicon carbide and carbon compounded on the carbon fibers. According to the invention, the carbon fiber is modified by adopting the modifier, the polymethylphenylsiloxane in the modifier is used as a main material, a silicon carbide ceramic film can be formed through subsequent high temperature, and is compounded on the surface of the carbon fiber, and the silicon carbide ceramic film can enhance the surface hardness and oxidation resistance of the carbon fiber, and improve the wear resistance and high temperature resistance of the carbon fiber, so that the service life of the carbon fiber in a vacuum high temperature furnace is prolonged. In addition, the carbon nano tube in the modifier can further enhance the mechanical property of the carbon fiber.

Inventors

  • QIAO XIAODONG
  • Zheng Xingdu
  • ZHU HAIXIANG
  • WANG ZHIQUN
  • ZHOU DIEHUI

Assignees

  • 浙江星辉新材料科技有限公司

Dates

Publication Date
20260512
Application Date
20240313

Claims (10)

  1. 1. The modified carbon fiber hard felt is characterized by comprising carbon fibers, and silicon carbide and carbon compounded on the carbon fibers; the modified carbon fiber hard felt is prepared by the following steps: Mixing a modifier with carbon fibers to obtain an intermediate, and sequentially carrying out hot press curing and carbonization on the intermediate to obtain a modified carbon fiber hard felt; The modifier comprises, by mass, 10-20% of polymethylphenylsiloxane, 10-30% of a viscosity regulator, 1-8% of carbon nanotubes, 3-7% of oily substances, 10-35% of a curing agent and 20-40% of pure water.
  2. 2. The modified carbon fiber hard felt according to claim 1, wherein the carbon fiber is selected from any one or more of polypropylene-based carbon fiber, pitch-based carbon fiber, or viscose-based carbon fiber.
  3. 3. The modified carbon fiber hard felt according to claim 1 or 2, wherein the mass ratio of the carbon fiber to the silicon carbide to the carbon is 2 (0.5-2): 0.5-2.
  4. 4. A method for preparing the modified carbon fiber hard felt according to any one of claims 1 to 3, comprising: Mixing a modifier with carbon fibers to obtain an intermediate, and sequentially carrying out hot press curing and carbonization on the intermediate to obtain a modified carbon fiber hard felt; The modifier comprises, by mass, 10-20% of polymethylphenylsiloxane, 10-30% of a viscosity regulator, 1-8% of carbon nanotubes, 3-7% of oily substances, 10-35% of a curing agent and 20-40% of pure water.
  5. 5. The preparation method of the modified polyurethane foam is characterized in that the modifier comprises, by mass, 12-15% of polymethylphenylsiloxane, 15-20% of a viscosity regulator, 2-6% of carbon nanotubes, 4-6% of an oily substance, 15-25% of a curing agent and 25-35% of pure water.
  6. 6. The method according to claim 4 or 5, wherein the viscosity modifier is selected from any one or more of industrial alcohol, acetone or methanol; the oily substance is selected from any one or more of kerosene, benzene or xylene; The curing agent is selected from any one or more of water-soluble phenolic resin, epoxy resin or polyester resin.
  7. 7. The method according to claim 6, wherein the water-soluble phenolic resin has a residual carbon content of 30 to 40% and a viscosity of 10 to 20 cp.
  8. 8. The method according to claim 6, wherein the hot press curing process is as follows: i, closing a pressing plate, wherein the pressure is 0.1-0.5 MPa, the temperature is 40-60 ℃ and the time is 1-3 hours; II, repeatedly opening and closing the pressing plate when the temperature is increased to 80-95 ℃, keeping the times of pressing for 1-5 times/min, wherein the pressure is 0.1-0.4 MPa, and the time is 0.5-1.5 h; III, heating to 130-160 ℃ and preserving heat for 3-6 hours.
  9. 9. The method according to claim 6, wherein the carbonization process comprises: I, heating from 0 ℃ to 300 ℃, wherein the heating time is 200-250 min, and preserving heat for 1-2 h at 300 ℃; II, heating from 300 ℃ to 800 ℃, wherein the heating time is 200-400 min, and preserving heat for 2-4 h at 800 ℃; III, heating from 800 ℃ to 1200 ℃ for 150-250 min, and preserving heat for 1-3 h at 1200 ℃; IV, heating from 1200 ℃ to 1850 ℃, wherein the heating time is 300-500 min, and preserving heat for 4-8 h at 1850 ℃.
  10. 10. A thermal insulation material characterized by comprising the modified carbon fiber hard felt according to any one of claims 1 to 3 or the modified carbon fiber hard felt prepared by the preparation method according to any one of claims 4 to 9.

Description

Modified carbon fiber hard felt and preparation method and application thereof Technical Field The invention belongs to the technical field of heat insulation materials, and particularly relates to a modified carbon fiber hard felt, a preparation method and application thereof. Background The carbon fiber heat insulation material is a soft felt material formed by carbon fibers and a certain proportion of binder, and is prepared into a hard carbon fiber heat insulation material by carbonization, graphitization and machining on the basis of the soft felt material. At present, a hard carbon fiber heat insulation material (carbon fiber hard felt for short) has the characteristics of high strength, high modulus, high dimensional stability, low density, small thermal expansion coefficient, thermal shock resistance, ablation resistance, good oxidation resistance and the like, and becomes the key point of many scholars to study. However, a vacuum high-temperature furnace is needed in the process of preparing the carbon fiber hard felt, and the service life of the common carbon fiber in the vacuum high-temperature furnace is short, so that the preparation of the carbon fiber hard felt is limited, and industrial batch production cannot be realized. Disclosure of Invention In view of the above, the present invention aims to provide a modified carbon fiber hard felt, and a preparation method and application thereof. The modified carbon fiber hard felt has longer service life in a vacuum high-temperature furnace, and is beneficial to realizing industrialized mass production. In order to achieve the purpose, the invention adopts the following technical scheme: In a first aspect, the present invention provides a modified carbon fiber hard felt comprising carbon fibers and silicon carbide and carbon composited on the carbon fibers. Preferably, the carbon fiber is selected from any one or more of polypropylene-based carbon fiber, pitch-based carbon fiber or viscose-based carbon fiber. Preferably, the mass ratio of the carbon fiber to the silicon carbide to the carbon is 2 (0.5-2): 0.5-2. In a second aspect, the present invention provides a method for preparing the modified carbon fiber hard felt, comprising: Mixing a modifier with carbon fibers to obtain an intermediate, and sequentially carrying out hot press curing and carbonization on the intermediate to obtain a modified carbon fiber hard felt; The modifier comprises, by mass, 10-20% of polymethylphenylsiloxane, 10-30% of a viscosity regulator, 1-8% of carbon nanotubes, 3-7% of oily substances, 10-35% of a curing agent and 20-40% of pure water. Preferably, the modifier comprises, by mass, 12-15% of polymethylphenylsiloxane, 15-20% of a viscosity regulator, 2-6% of carbon nanotubes, 4-6% of an oily substance, 15-25% of a curing agent and 25-35% of pure water. Preferably, the viscosity modifier is selected from any one or more of industrial alcohol, acetone or methanol. Preferably, the oily substance is selected from any one or more of kerosene, benzene or xylene. Preferably, the curing agent is selected from any one or more of water-soluble phenolic resin, epoxy resin or polyester resin. Preferably, the residual carbon content of the water-soluble phenolic resin is 30-40%, and the viscosity is 10-20 cp. Preferably, the hot press curing process is as follows: i, closing a pressing plate, wherein the pressure is 0.1-0.5 mpa, the temperature is 40-60 ℃ and the time is 1-3 hours; II, repeatedly opening and closing the pressing plate when the temperature is increased to 80-95 ℃, keeping the times of pressing at 1-5 times/min, wherein the pressure is 0.1-0.4 mpa, and the time is 0.5-1.5 h; III, heating to 130-160 ℃ and preserving heat for 3-6 hours. Preferably, the carbonization process is as follows: I, heating from 0 ℃ to 300 ℃, wherein the heating time is 200-250 min, and preserving heat for 1-2 h at 300 ℃; II, heating from 300 ℃ to 800 ℃, wherein the heating time is 200-400 min, and preserving heat for 2-4 h at 800 ℃; III, heating from 800 ℃ to 1200 ℃ for 150-250 min, and preserving heat for 1-3 h at 1200 ℃; IV, heating from 1200 ℃ to 1850 ℃, wherein the heating time is 300-500 min, and preserving heat for 4-8 h at 1850 ℃. In a third aspect, the invention provides a heat insulation material, which comprises the modified carbon fiber hard felt related to the technical scheme. Compared with the prior art, the invention has the beneficial effects that: The invention provides a modified carbon fiber hard felt, which comprises carbon fibers, and silicon carbide and carbon compounded on the carbon fibers. In the invention, the modified carbon fiber hard felt is prepared by mixing a modifier with carbon fibers to obtain an intermediate, and sequentially carrying out hot press solidification and carbonization on the intermediate. According to the invention, the carbon fiber is modified by adopting the modifier, the polymethylphenylsiloxane in the modifier is used as a main materia