A kind of preparation method of pitch-based carbon fiber with hollow cross-section structure

Abstract

The invention discloses a method for preparing a pitch-based carbon fiber with a hollow cross-section structure. The oil-based mesophase pitch with a mesophase content of 95-98% and a thermal weight loss of 3-6% at a constant temperature of 330°C for 3 hours is used as a raw material, relying on twin-screws. Carry out continuous melting and conveying, use metering pumps for precise metering, and then enter the spinning assembly for more than 3 hours of uniform temperature treatment. After the metering pump pumps, the built-up pressure exceeds 5MPa and passes through 1000 round holes with a diameter of 0.1mm and a hole length of 0.5mm. The spinneret is extruded into filaments, oiled and clustered to obtain continuous pitch fiber filaments with a hollow cross-section structure; then pre-oxidized, low-temperature carbonization and high-temperature carbonization to prepare pitch-based carbon fibers with a hollow cross-section structure. The invention can realize the controllable preparation of the hollow cross-section structure only by adjusting the components of the mesophase pitch and its thermal stability, the technical route is simple, and it is very easy to realize industrialization. application prospects.

Description

technical field [0001] The invention belongs to the technical field of pitch-based carbon fiber preparation technology, and specifically relates to a method of controlling the components of mesophase pitch for spinning and its thermal stability, and then matching a suitable spinning process to realize the continuous production of pitch fibers with a hollow cross-section structure. spinning. Background technique [0002] Modern warfare has higher and higher requirements for weapons and equipment. The development of structural absorbing materials with wide absorption frequency band, high absorption efficiency, low density and multi-band compatibility has become a research hotspot. [0003] Carbon fiber is one of the more commonly used fiber types for structural absorbing materials, but carbon fiber with high electrical conductivity has strong reflection characteristics for electromagnetic waves, so it must be modified to prepare carbon fibers with special structures. Common m...

AI Technical Summary

Problems solved by technology

Li Mingwei and Wang Chengyang of Tianjin University and others ("Carbon", 1996, 4: 14-18) respectively used two different mesophase pitches as raw materials, and used special-shaped slit-type spinnerets to spin hollow cross-section structural fibers. , to realize the spinning of hollow structure and solid fiber, but the slit-type spinneret is not easy to process, it is difficult to realize industrial production, and the batch preparation is limited

[0005] It can be seen that for the preparation methods of pitch-based carbon fibers with hollow cross-section structures, there is no method that is particularly suitable for industrial production. It is of great significance to develop a preparation method that is simple in process and easy to realize industrialization, which can promote It is widely used in the fields of lithium battery negative electrode, energy storage and wave absorption

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