Manufacturing method of polyimide/polyacrylonitrile-based blended pre-oxidized fiber

Abstract

The invention discloses a manufacturing method of a polyimide / polyacrylonitrile-based blended pre-oxidized fiber and belongs to the technical field of fibers. The manufacturing method comprises the following steps: uniformly mixing a PAA spinning solution and a PAN spinning solution by virtue of a mechanical blending method to obtain a PAA / PAN mixed spinning solution, and obtaining a PAA / PAN blended primary fiber by virtue of wet method / dry-wet method spinning, wherein the mass fraction of PAN, occupying PAA (without counting the solvent), is 2-80 percent; and in the heat treatment process, carrying out 4-segement thermal drying treatment, with the temperature range of 60-160 DEG C, by virtue of a layer-based thermal stabilization furnace, carrying out 4-segement pre-oxidization treatment, with the temperature range of 180-300 DEG C, and finally obtaining the PI / PAN blended pre-oxidized fiber. According to the manufacturing method disclosed by the invention, by virtue of uniform blending of the two components, the two components have the synergistic effect in the heat treatment process; under the same condition, compared with the pure component, the imidization degree and the pre-oxidization degree of the blended fiber are both promoted and improved, and the blended fiber keeps high performance and can be directly used as high-performance fiber or used for preparing carbon fibers.

Description

technical field [0001] The invention belongs to the field of fiber technology, in particular to a method for manufacturing polyimide (PI) and polyacrylonitrile (PAN) blended preoxidized fibers. Background technique [0002] There are many raw materials for preparing carbon fiber, such as polyacrylonitrile (PAN), pitch, viscose fiber, cellulose fiber, phenolic, polybenzothiazole, etc., but currently only viscose-based carbon fiber, PAN-based carbon fiber and There are three types of pitch-based carbon fibers. Viscose-based carbon fiber is mainly used as ablation-resistant and heat-insulating materials, but its output is low, less than 1% of the world's total carbon fiber output; PAN-based carbon fiber has high strength and modulus, and the production process is simple. More than 90% of the total output of carbon fiber; pitch-based carbon fiber prepared from mesophase pitch has better heat transfer, electrical conductivity and lower thermal expansion coefficient than PAN-base...

AI Technical Summary

Problems solved by technology

Viscose-based carbon fiber is mainly used as ablation-resistant and heat-insulating materials, but its output is low, less than 1% of the world's total carbon fiber output; PAN-based carbon fiber has high strength and modulus, and the production process is simple. More than 90% of the total output of carbon fiber; pitch-based carbon fiber prepared from mesophase pitch has better heat transfer, electrical conductivity and lower thermal expansion coefficient than PAN-based carbon fiber, but due to pitch-based carbon fiber has higher requirements for the selection of raw materials , high thermal conductivity carbon fibers can only be obtained under strict control of raw materials and processes. At the same time, there are still problems in the preparation of pitch matrix, mainly because the preparation of mesophase pitch with good performance and high stability is difficult, which greatly hinders Development of pitch-based carbon fibers

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