A method of producing a fiber is provided, the method including extruding, from a spinneret, a spinning dope solution containing a fiber-forming polymer dissolved in a solvent, once allowing the solution to run in air, and then guiding the solution into the liquid of a coagulation bath to allow coagulation, wherein a gas-phase portion formed in a vertically downward direction from an extrusion surface of the spinneret to the liquid surface of the coagulation bath has a unidirectional air flow, and has an air flow rate per unit time (Af) which satisfies, in relation to the amount of the solvent in the spinning dope solution per unit time (As) in the gas-phase-portion volume (Vh), the relational expression 0.0008 m.sup.3≤Af/(As/Vh)≤0.0015 m.sup.3. A method of producing a fiber, which, in dry-jet wet spinning, suppresses occurrence of dew condensation in the spinneret, and reduces deterioration of the appearance caused by winding on rollers in the subsequent process or by fuzzing or yarn break in the stretching process, to enable significant improvement of the productivity and the appearance as a whole, is provided.

Carbon fiber precursor treatment agents include a nonionic surfactant, an amino-modified silicone, and a dimethyl silicone with a kinematic viscosity at 25° C. of 5 to 200 mm.sup.2/s. The mass ratio of the content of the amino-modified silicone with respect to the content of the dimethyl silicone is 99.9/0.1 to 90/10. Alternatively, when the total content of the nonionic surfactant, the amino-modified silicone, and the dimethyl silicone is taken as 100 parts by mass, the nonionic surfactant is contained at a ratio of 9 to 85 parts by mass, the amino-modified silicone is contained at a ratio of 10 to 90.9 parts by mass, and the dimethyl silicone is contained at a ratio of 0.1 to 5 parts by mass.

The present invention relates to 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. The method controls the viscosity of the spinning stock solution to improve the stretchability and strength of the acrylonitrile-based fiber, and suppresses the occurrence of gelation.

A simplified and improved process is described for the production of acrylic fibers, in particular a process for preparing a spinning solution for the production of acrylic fibers.

Disclosed are a method for a preparing fluorine- and chlorine-containing conductive polymer resin, a single-side or double-side filled composite film prepared using the fluorine- and chlorine-containing conductive polymer resin, and a method for preparing the film. The fluorine- and chlorine-containing conductive polymer single-side or double-side filled composite film comprises a microporous film skeleton and the fluorine- and a chlorine-containing conductive polymer resin. The composite film is mechanically stronger, more waterproof, more impervious to water and toxic and harmful chemicals, and more moisture permeability. When applied to biochemical protective clothing, it can greatly enhance the combat effectiveness of the soldiers because it is light and more impervious to water and toxic and harmful chemicals, brings about comfort, and keeps the soldiers warm. When applied to fuel cells, it can provide better electrical properties due to its high conductivity and can allow the fuel, such as hydrogen or alcohol, to burn more completely.

A polymer comprising repeating units derived from a first monomer, typically acrylonitrile, and repeating units derived from a second monomer different from the first monomer, wherein the second monomer is a compound comprising an ethylenically unsaturated organic anion and an organic cation containing a C═N imine group; a process for producing carbon fibers using the said polymer; and carbon fibers made therefrom, are described herein.

A polymer comprising repeating units derived from a first monomer, typically acrylonitrile, and repeating units derived from a second monomer different from the first monomer, wherein the second monomer is a compound comprising an ethylenically unsaturated organic anion and an organic cation containing a C═N imine group; a process for producing carbon fibers using the said polymer; and carbon fibers made therefrom, are described herein.

Provided is a method of preparing an acrylonitrile-based copolymer for a carbon fiber, which comprises: preparing a reaction solution including a monomer mixture comprising a sulfonate-based monomer represented by Chemical Formula 1, a carboxylic acid-based monomer, and an acrylonitrile-based monomer and an organic solvent; and subjecting the reaction solution to polymerization, wherein the monomer mixture comprises the sulfonate-based monomer represented by Chemical Formula 1 at 0.55 to 1.6 mol %.

The present disclosure relates to a process for producing carbon fibers utilizing a salt of an organic cation containing C═N imine group, and carbon fibers produced by such process.

Provided is an acrylonitrile-based copolymer for a carbon fiber which includes a sulfonate-based monomer unit, a carboxylic acid-based monomer unit, and an acrylonitrile-based monomer unit, and the acrylonitrile-based copolymer for a carbon fiber includes the sulfonate-based monomer unit at 0.55 to 1.55 mol %, and the carboxylic acid-based monomer unit at 0.60 to 1.40 mol %.