A method and apparatus for manufacturing a carbon fiber. Pressure is applied to a filament to change a cross-sectional shape of the filament and create a plurality of distinct surfaces on the filament. The filament is converted into a graphitic carbon fiber having the plurality of distinct surfaces. A plurality of sizings is applied to the plurality of distinct surfaces of the graphitic carbon fiber in which the plurality of sizings includes at least two different sizings.

A method and apparatus for manufacturing a carbon fiber. Pressure is applied to a filament to change a cross-sectional shape of the filament and create a plurality of distinct surfaces on the filament. The filament is converted into a graphitic carbon fiber having the plurality of distinct surfaces. A plurality of sizings is applied to the plurality of distinct surfaces of the graphitic carbon fiber in which the plurality of sizings includes at least two different sizings.

This invention innovates a low cost method to synthesize carbon fibers through graphene composites, which are fabricated through chemical treatment of graphite. This invention also is related to the applications of thereof carbon fibers in different fields. Several examples of such fields would be to use carbon fibers to manufacture carbon fiber tubes, pipes or risers, or car/airplane/computer parts, bicycles, and sports supplies and many additional applications.

This invention innovates a low cost method to synthesize carbon fibers through graphene composites, which are fabricated through chemical treatment of graphite. This invention also is related to the applications of thereof carbon fibers in different fields. Several examples of such fields would be to use carbon fibers to manufacture carbon fiber tubes, pipes or risers, or car/airplane/computer parts, bicycles, and sports supplies and many additional applications.

There is provided a method of making a hollow fiber. The method includes mixing, in a first solvent, a plurality of nanostructures, one or more first polymers, and a fugitive polymer which is dissociable from the nanostructures and the one or more first polymers, to form an inner-volume portion mixture. The method further includes mixing, in a second solvent, one or more second polymers to form an outer-volume portion mixture, and spinning the inner-volume portion mixture and the outer-volume portion mixture to form a precursor fiber. The method further includes heating the precursor fiber to oxidize the precursor fiber and to change a molecular-bond structure of the precursor fiber, and during heating, extracting the fugitive polymer from the inner-volume portion mixture. The method further includes obtaining the hollow fiber with the inner-volume portion having the nanostructures and the first polymers, and with the outer-volume portion having the second polymers.

There is provided a method of making a hollow fiber. The method includes mixing, in a first solvent, a plurality of nanostructures, one or more first polymers, and a fugitive polymer which is dissociable from the nanostructures and the one or more first polymers, to form an inner-volume portion mixture. The method further includes mixing, in a second solvent, one or more second polymers to form an outer-volume portion mixture, and spinning the inner-volume portion mixture and the outer-volume portion mixture to form a precursor fiber. The method further includes heating the precursor fiber to oxidize the precursor fiber and to change a molecular-bond structure of the precursor fiber, and during heating, extracting the fugitive polymer from the inner-volume portion mixture. The method further includes obtaining the hollow fiber with the inner-volume portion having the nanostructures and the first polymers, and with the outer-volume portion having the second polymers.

An oil agent for a carbon fiber precursor is provided that contains a base component, a cationic surfactant, and a nonionic surfactant, wherein the cationic surfactant is a specific nitrogen-containing compound.

A manufacturing method and an apparatus enable high productivity. A method for manufacturing an oxidized fiber bundle includes joining an upstream precursor fiber bundle and a downstream precursor fiber bundle together with a joining fiber bundle, and oxidizing the joined precursor fiber bundles by feeding the joined precursor fiber bundles through an oxidization furnace. The joining includes applying an oiling agent to a joint area of a joining target precursor fiber bundle before joining the joining target precursor fiber bundle and the joining fiber bundle together. A quantity of the oiling agent adhering to the joint area is 0.15 to 0.85 wt %.

The present invention relates to a process and an apparatus for recovering (recycling) carbon fibers from carbon fiber-containing plastics, in particular from carbon fiber-reinforced plastics (CFPs), preferably from carbon fiber-containing and/or carbon fiber-reinforced composites (composite materials), and also to the recycled carbon fibers obtainable by the process according to the invention and the use thereof.

The present invention relates to a process and an apparatus for recovering (recycling) carbon fibers from carbon fiber-containing plastics, in particular from carbon fiber-reinforced plastics (CFPs), preferably from carbon fiber-containing and/or carbon fiber-reinforced composites (composite materials), and also to the recycled carbon fibers obtainable by the process according to the invention and the use thereof.