CROSS REFERENCE TO RELATED APPLICATIONS

This application is National Phase Entry pursuant to U.S.C. 371 of International Application No PCT/KR2018/011440 filed Sep. 27, 2018, and claims the benefit of Korean Patent Application No. 10-2017-0127618, filed on Sep. 29, 2017, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

TECHNICAL FIELD

The present invention relates to a method for producing an acrylonitrile-based fiber using a spinning stock solution subjected to hydrophilization treatment.

BACKGROUND ART

A carbon fiber is a fibrous carbon material having a carbon amount of 90% or more by weight, and indicates a fiber obtained by pyrolyzing a fiber-shaped precursor prepared from polyacrylonitrile (PAN), pitch which is a petroleum-based or coal-based hydrocarbon residue, or rayon in an inert atmosphere.

The carbon fiber is a material having structural and textural characteristics as a carbon material present in constituent elements and also having the fibrous form, and the carbon material has excellent characteristics such as heat resistant, chemical stability, electro-thermal conductivity, dimensional stability due to low thermal expansion, low density, friction wear characteristics, X-ray transparency, electromagnetic wave shielding property, biocompatibility and flexibility, and may also impart very good adsorption characteristics depending on the activation conditions.

Meanwhile, the acrylonitrile-based copolymer is widely being used as a raw material of a carbon fiber precursor. Generally, the acrylonitrile-based copolymer is dissolved in an organic solvent or an inorganic solvent to prepare a spinning stock solution, followed by wet spinning, dry spinning or wet-dry spinning to be produced in the fibrous form, and followed by coagulation, washing, stretching and drying to be capable of obtaining an acrylonitrile-based fiber.

In order to secure stability by accelerating flame retardation treatment of a precursor fiber in the production of a flame-resistant fiber using the acrylonitrile-based copolymer, a method for preparing an acrylonitrile-based copolymer by copolymerizing a small amount of monomers containing a carboxylic acid group together with acrylonitrile is widely used. In the wet or wet-dry spinning using the spinning stock solution prepared with the acrylonitrile-based copolymer prepared thus, in order to increase the hydrophilicity of the spinning stock solution and suppress micro or macro voids, there is proposed a method for ionizing the above-described carboxylic acid group using ammonia water. However, the ammonia water introduced in order to ionize the carboxylic acid group is easy to generate a gel polymer in the spinning stock solution, and such a gel polymer acts as a foreign matter in the spinning process of the spinning stock solution containing the acrylonitrile-based fiber, so that the production stability and the operability may be deteriorated.

PRIOR ART DOCUMENT

Patent Document

(Patent Document 1) KR1999-0035887A

DISCLOSURE OF THE INVENTION

Technical Problem

An aspect of the present invention provides a method for producing an acrylonitrile-based fiber that can improve productivity, stability and operability.

Technical Solution

According to an aspect of the present invention, there is provided a method for producing an acrylonitrile-based fiber, the method including: providing a polymer solution including an acrylonitrile-based copolymer containing a carboxylic acid group; mixing 100 parts by weight of the polymer solution with 1 to 6 parts by weight of a hydrophilization solution containing an organic solvent and ammonia water in a weight ratio of 95:5 to 60:40 to prepare a spinning stock solution; and spinning the spinning stock solution.

Advantageous Effects

A method for producing an acrylonitrile-based fiber according to the present invention may utilize ammonia water under specific conditions in the process of hydrophilizing an acrylonitrile-based copolymer, thereby suppressing the generation of gel polymers to be generated, controlling viscosity through the hydrophilization treatment, and thus improving the stretchability and strength of spinning fibers and easily performing the spinning, so that the productivity, stability and operability of the acrylonitrile-based fiber may be improved.

