Disclosed is an apparatus for manufacturing a carbon nanotube fiber.

The present invention relates to an apparatus for producing a carbon nanotube fiber. The apparatus includes: a vertical reactor having a reaction zone; a concentric double-pipe inlet tube disposed on top of the reaction zone and consisting of an inner pipe through which a spinning feedstock including a spinning solution and a first gas is introduced into the reaction zone and an outer pipe defining a concentric annular portion surrounding the inner pipe and through which a second gas is introduced into the reaction zone; heating means for heating the reaction zone; and a discharge unit disposed under the bottom of the reaction zone to discharge a carbon nanotube fiber therethrough. The spinning feedstock entering the reaction zone through the inner pipe of the inlet tube is carbonized and graphitized while flowing from the top to the bottom of the reaction zone to form a carbon nanotube fiber consisting of a continuous sock (or aggregates) of carbon nanotubes. The second gas entering the reaction zone through the outer pipe of the inlet tube forms a gas curtain surrounding the circumference of the continuous sock of carbon nanotubes while flowing from the top to the bottom of the reaction zone. The gas curtain minimizes the contamination of the inner wall of the reactor and facilitates the discharge of the carbon nanotube fiber. Therefore, the apparatus of the present invention is suitable for the production of a carbon nanotube fiber in a continuous manner.

The present invention relates to an apparatus for producing a carbon nanotube fiber. The apparatus includes: a vertical reactor having a reaction zone; a concentric double-pipe inlet tube disposed on top of the reaction zone and consisting of an inner pipe through which a spinning feedstock including a spinning solution and a first gas is introduced into the reaction zone and an outer pipe defining a concentric annular portion surrounding the inner pipe and through which a second gas is introduced into the reaction zone; heating means for heating the reaction zone; and a discharge unit disposed under the bottom of the reaction zone to discharge a carbon nanotube fiber therethrough. The spinning feedstock entering the reaction zone through the inner pipe of the inlet tube is carbonized and graphitized while flowing from the top to the bottom of the reaction zone to form a carbon nanotube fiber consisting of a continuous sock (or aggregates) of carbon nanotubes. The second gas entering the reaction zone through the outer pipe of the inlet tube forms a gas curtain surrounding the circumference of the continuous sock of carbon nanotubes while flowing from the top to the bottom of the reaction zone. The gas curtain minimizes the contamination of the inner wall of the reactor and facilitates the discharge of the carbon nanotube fiber. Therefore, the apparatus of the present invention is suitable for the production of a carbon nanotube fiber in a continuous manner.

Disclosed herein are processes for preparing carbon fibers, comprising: sulfonating a polymer fiber with a sulfonating agent that is fuming sulfuric acid, sulfuric acid, chlorosulfonic acid, or a combination thereof; treating the sulfonated polymer with a heated solvent, wherein the temperature of the heated solvent is at least 95° C.; and carbonizing the resulting product by heating it to a temperature of 500-3000° C. Carbon fibers prepared according to these methods are also disclosed herein.

Disclosed herein are processes for preparing carbon fibers, comprising: sulfonating a polymer fiber with a sulfonating agent that is fuming sulfuric acid, sulfuric acid, chlorosulfonic acid, or a combination thereof; treating the sulfonated polymer with a heated solvent, wherein the temperature of the heated solvent is at least 95° C.; and carbonizing the resulting product by heating it to a temperature of 500-3000° C. Carbon fibers prepared according to these methods are also disclosed herein.

A carbon fiber bundle having a high abrasion resistance property and simultaneously being excellent in widening property is provided by a carbon fiber bundle with an adhered sizing agent including a carbon fiber bundle, and a sizing agent adhered to a surface of the carbon fiber bundle, wherein the sizing agent contains an epoxy compound, and shows an intersection of a storage modulus and a loss modulus at an angular frequency in the range of 1×10.sup.5 to 1×10.sup.9 rad/sec in a measurement at 25° C.

Disclosed is a method of forming a conductive diamond layer on a surface of a carbon fibre substrate that is used as a component of an electrode for neural stimulation and/or electrochemical sensing. The method comprises functionalising at least a portion of the surface with a functionalising agent to facilitate coating the surface with the conductive diamond layer. The method also comprises providing a diamond precursor and depositing the diamond precursor over the functionalising agent to form the conductive diamond layer. The disclosure also relates to an electrode that is used as a component of an electrode for neural stimulation and/or electrochemical sensing.

The present invention relates to a method for enhancing tensile strength of a carbon nanotube (CNT) fiber aggregate, comprising dispersing a CNT fiber aggregate with chlorosulfonic acid (CSA), followed by thermal treatment, wherein a particular magnitude of tension is applied upon the thermal treatment, whereby the CNT fiber aggregate is increased in alignment level and tensile strength.

The surface of a carbon fiber is electrochemically treated by a method to form nitrogen containing groups on the surface of the carbon fiber. The method comprises contacting a carbon fiber surface with an aqueous solution comprised of a non-cyclic aliphatic amine and water soluble inorganic hydroxide with said aqueous solution having a pH of at least 9. A positive electrical bias is then applied to the carbon fibers in the aqueous solution relative to another electrode in contact with the aqueous solution, wherein the positive electrical bias is at a voltage above the oxidation potential of water. The treated carbon fibers are useful for making epoxy reinforced carbon fiber composites.

A method for manufacturing a carbon fiber is provided which involves: (1) immersing a carbon fiber composite material (CFC) in an acidic aqueous solution to elute at least a part of a resin component of the CFC, to thereby obtain a substantially fibrous product; and (2) immersing the substantially fibrous product obtained in step (1) in an alkaline aqueous solution to elute at least a part of a resin component of the substantially fibrous product, to thereby obtain a fibrous product. A method for manufacturing a carbon fiber reinforced resin composition is provided which involves manufacturing a carbon fiber by the above method and manufacturing a carbon fiber reinforced resin composition using the resulting carbon fiber. Using these methods, it is possible to recover and recycle a carbon fiber from a carbon fiber composite material (CFC) at a low cost without deteriorating the carbon fiber.