A method for manufacturing carbon fiber, the method includes: placing a carbon fiber as an anode in an electrolyte, wherein the electrolyte is nitric acid, sulfuric acid, phosphoric acid, acetic acid, ammonium bicarbonate, sodium hydroxide, or potassium nitrate; and performing a surface treatment, wherein a surface of the carbon fiber is oxidized by active oxygen generated by anodic electrolysis, and thereby oxygen-containing functional groups are introduced to the surface. The disclosure also provides a carbon fiber composite bottle, which includes a bottle body and a carbon fiber. The bottle body is a type III bottle or a type IV bottle. The carbon fiber surrounds the bottle body, the surface oxygen concentration of the carbon fiber is 5-35%, and the surface roughness of the carbon fiber is 5-25 nm.

The present invention provides a carbon fiber, which has excellent tensile strength by having fewer internal defects while being a thick fiber having a single-fiber diameter of 6.0 μm or greater, and can provide the effects of reducing costs while increasing production amount to enhance the yieldability of the carbon fiber.

A manufacturing method for a carbon fiber includes: performing an emulsification step that includes uniformly mixing a silicone oil composition and an emulsifier to form an oiling agent, in which the silicone oil composition includes γ-divinyltriamine propylmethyldimethoxyl silane and N-(β-aminoethyl)-γ-aminopropylmethylbimethoxy silane; performing an oiling step that includes soaking a carbon raw filament in the oiling agent, such that the oiling agent is adhered to a surface of the carbon raw filament to form a carbon fiber precursor; and performing a calcination step on the carbon fiber precursor, such that the carbon fiber is formed.

An object of the present invention is to provide a carbon fiber which exhibits excellent strength development rate when used in a composite material. The present invention that solves the problems is a carbon fiber which simultaneously satisfies the following formulae (1) and (2):

Lc/d≤3  (1)

TS×d×Lc>6.0×10.sup.5  (2) wherein: Lc is an X-ray crystallite size (Å), d is a filament diameter (μm), and TS is a strand tensile strength (MPa).

An object of the present invention is to provide a carbon fiber which exhibits excellent strength development rate when used in a composite material. The present invention that solves the problems is a carbon fiber which simultaneously satisfies the following formulae (1) and (2):

Lc/d≤3  (1)

TS×d×Lc>6.0×10.sup.5  (2) wherein: Lc is an X-ray crystallite size (Å), d is a filament diameter (μm), and TS is a strand tensile strength (MPa).

A method of producing a stabilized fiber, including performing a heat treatment on an acrylamide polymer fiber under an oxidizing atmosphere in a stabilization treatment temperature range of 200° C. to 500° C. while applying a tension of 0.07 mN/tex to 15 mN/tex.

A quad-polymer composition includes monomers of (a) acrylonitrile, (a) vinylimidazole, (c) methyl acrylate and (d) either acrylic acid or itaconic acid. Such quad-polymer compositions may be used to form fibers (such as by melt spinning) that may then be annealed, stabilized, and/or carbonized to produce carbon fibers. The quad-polymer composition may be used for supercapacitors, lithium battery electrodes once carbonized, and as synthesized, it may be used for wound healing fibers, fabrics, coatings, and films, and anti-bacterial/anti-microbial fibers, fabrics, coatings and films. The carbon fibers formed from the quad-polymer composition may be used for the fiber composites for automobile, aerospace structures, marine structures, military equipment/parts, sporting goods, robotics, furniture, and electronic parts.

A quad-polymer composition includes monomers of (a) acrylonitrile, (a) vinylimidazole, (c) methyl acrylate and (d) either acrylic acid or itaconic acid. Such quad-polymer compositions may be used to form fibers (such as by melt spinning) that may then be annealed, stabilized, and/or carbonized to produce carbon fibers. The quad-polymer composition may be used for supercapacitors, lithium battery electrodes once carbonized, and as synthesized, it may be used for wound healing fibers, fabrics, coatings, and films, and anti-bacterial/anti-microbial fibers, fabrics, coatings and films. The carbon fibers formed from the quad-polymer composition may be used for the fiber composites for automobile, aerospace structures, marine structures, military equipment/parts, sporting goods, robotics, furniture, and electronic parts.

A vehicle includes a vehicle body and a vehicle propulsion system. The vehicle propulsion system includes a fuel tank having a nozzle and a tank body. The tank body is made, at least in part, from carbon fiber materials. A method of producing a carbon fiber component for the vehicle is also described.

A vehicle includes a vehicle body and a vehicle propulsion system. The vehicle propulsion system includes a fuel tank having a nozzle and a tank body. The tank body is made, at least in part, from carbon fiber materials. A method of producing a carbon fiber component for the vehicle is also described.