Carbon fiber precursor high pressure steam drafting machine

Abstract

A novel carbon fiber protofilament high-pressure steam draw machine is provided. The machine comprises a drawing tank body and labyrinth seal box bodies. The drawing tank body is provided with slits through which tows pass. The inner bottom of the drawing tank body is provided with a low-pressure steam feeding pipeline. A porous distributing plate is disposed above the low-pressure steam feeding pipeline. The inlet end and the outlet end of the drawing tank body are respectively provided with the labyrinth seal box bodies. An upper labyrinth seal structure and a lower labyrinth seal structure are disposed in each of the labyrinth seal box bodies. A gap is formed between the corresponding upper and lower labyrinth seal structures to form a tow passing path. The machine is high in drawing rate, low in fiber fracture, high in tow passing rate, good in pressure keeping performance, and capable of effectively improving degrees of orientation and crystallinity of protofilaments, and is a critical device for preparing protofilaments used for high-performance carbon fibers.

Description

technical field [0001] The invention relates to a carbon fiber precursor high-pressure steam drafting machine. Background technique [0002] Carbon fiber is an inorganic polymer fiber with a carbon content of more than 90%. In addition to the high temperature resistance, friction resistance, electrical conductivity, thermal conductivity and corrosion resistance of general carbon materials, it also has soft machinability, light weight, and specific strength. With high specific modulus, it is a new generation of reinforced materials, widely used in sports equipment, textiles, chemical machinery, medicine, military, and many cutting-edge technology fields. [0003] The output of polyacrylonitrile-based carbon fiber accounts for more than 80% of various carbon fiber materials, but the quality of PAN precursor is still a bottleneck in the development of carbon fiber. [0004] Polymerized stock solution is solidified and formed into primary fibers. After washing, drawing, drying,...

AI Technical Summary

Problems solved by technology

[0005] In terms of equipment, the high-pressure steam drawing process is a key process in the production of carbon fiber precursors. The domestic steam drawing equipment is unstable in operation and poor in sealing performance, which causes fluctuations in the steam flow and temperature in the drawing tank, which are prone to hair and broken filaments. The productivity of the production line is reduced, the production cost is increased, and the high-power drafting process is affected, thereby reducing the orientation degree and crystallinity of the raw silk, reducing the physical and chemical properties of the raw silk, and increasing the degree of dispersion, which ultimately affects the mechanical properties of carbon fibers.

[0006] In terms of technology, currently foreign countries use high-temperature and high-pressure steam methods, while most domestic carbon fiber manufacturers draw under low-temperature steam, so high-temperature water molecules cannot be fully and evenly entered into the silk, and solvent molecules cannot be fully released. , After high-power steam drawing, the pores in the fiber become larger and more in number, the total volume of the holes in the fiber increases greatly, and the degree of orientation also decreases significantly. The high-power steam drawing process fails to effectively improve the physical and chemical properties of the fiber.

Under the condition of low temperature (≤130℃), the superheated steam stretches 2.5 to 3 times, although the number of micropores in the fiber decreases, but the length of the micropores is still long and the diameter is large. Basically, the quality of the high-performance carbon fiber produced by this precursor is not Stablize

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