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.