Method for reducing production of preoxidized broken filament during preparation of polyacrylonitrile-based carbon fiber

Abstract

The invention discloses a method for reducing the production of preoxidized broken filament during the preparation of polyacrylonitrile-based carbon fiber, characterized in that: dipping: polyacrylonitrile-based carbon fiber precursor is dipped with pure water until the water content in the precursor is 5-15wt%; or polyacrylonitrile-based carbon fiber precursor is dipped with epoxy ethane modified silicone oil emulsion or ammonia modified silicone oil emulsion until the water content in the precursor is 5-15wt% and attached amount of oil is 0.5-1wt%; and shaping: the dipped precursor is subject to shaping. Owing to the effect of surface tension of the pure water, a fiber bundle dipped with the pure water is increased in convergence property, and the generated broken filaments are adhered to the fiber bundle; a layer of protective film is formed on the surface of fiber by using the fiber bundle dipped with the oil emulsion, thereby preventing inter-fiber adhesion and doubling and simultaneously avoiding the physical damage to fibers by furnace rollers; and the shaping treatment can effectively relieve the internal stress generated in the production process of the precursor, thereby avoiding fibers from tension fracture in the process of preoxidation.

Description

technical field [0001] The invention relates to a method for preparing polyacrylonitrile-based carbon fibers, in particular to a method for reducing the generation of pre-oxidized fuzz in the preparation of polyacrylonitrile-based carbon fibers. Background technique [0002] During the preparation of polyacrylonitrile-based carbon fibers, the pre-oxidation stage is the most time-consuming stage. In the pre-oxidation process, the fiber passes through multiple active drafting rolls, guide rolls and other roll bodies. Repeated contact with the roller body will cause surface damage to the fiber, and if the resulting fluff is not handled in time, it is easy to entangle the roller, which will affect the stability of production. Multiple drafts during the production process of the raw silk will lead to an increase in the internal stress of the fiber, making it difficult to carry out the drafting in the pre-oxidation stage. Contents of the invention [0003] The technical proble...

AI Technical Summary

Problems solved by technology

Repeated contact with the roller body will cause surface damage to the fiber, and if the resulting fluff is not handled in time, it is easy to entangle the roller, which will affect the stability of production

Multiple drawing during the raw silk production process will lead to an increase in the internal stress of the fiber, making it difficult to carry out the drawing in the pre-oxidation stage