In a method of making a carbon fiber, PAN (poly(acrylonitrile-co methacrylic acid)) is dissolved into a solvent to form a PAN solution. The PAN solution is extruded through a spinneret, thereby generating at least one precursor fiber. The precursor fiber is passed through a cold gelation medium, thereby causing the precursor fiber to gel. The precursor fiber is drawn to a predetermined draw ratio. The precursor fiber is continuously stabilized to form a stabilized fiber. The stabilized fiber is continuously carbonized thereby generating the carbon fiber. The carbon fiber is wound onto a spool. A carbon fiber has a fiber tensile strength in a range of 5.5 GPa to 5.83 GPa. The carbon fiber has a fiber tensile modulus in a range of 350 GPa to 375 GPa. The carbon fiber also has an effective diameter in a range of 5.1 m to 5.2 m.

A carbon nanotube array constituted by large numbers of carbon nanotubes vertically aligned on a substrate is produced by supplying a carbon source gas into a reaction vessel having a hydrogen gas atmosphere, in which a substrate on which a reaction catalyst comprising fine metal particles is formed is placed; forming large numbers of vertically aligned carbon nanotubes on the substrate by keeping a reaction temperature of 500-1100 C. for 0.5-30 minutes; and heat-treating the carbon nanotubes by stopping the supply of the carbon source gas and keeping 400-1100 C. for 0.5-180 minutes in a non-oxidizing atmosphere.

A carbon nanotube array constituted by large numbers of carbon nanotubes vertically aligned on a substrate is produced by supplying a carbon source gas into a reaction vessel having a hydrogen gas atmosphere, in which a substrate on which a reaction catalyst comprising fine metal particles is formed is placed; forming large numbers of vertically aligned carbon nanotubes on the substrate by keeping a reaction temperature of 500-1100 C. for 0.5-30 minutes; and heat-treating the carbon nanotubes by stopping the supply of the carbon source gas and keeping 400-1100 C. for 0.5-180 minutes in a non-oxidizing atmosphere.

The present invention provides an improved fiber precursor, and methods for employing such to enhance the structural reinforcement of composite structures. The precursor is comprised of one or more fibrous filaments positioned within the precursor so that the filaments within each fiber are oriented at an angle offset from the axis of the length of the precursor. The offset of these filaments can be accomplished, for example, by twisting a plurality of filaments into a continuous spiral to form the precursor, or by wrapping a collection of colinear filaments about a central core, or by braiding plurality of filaments to form the precursor. The angle of offset at which the twisted, braided or wrapped fibers are positioned can be varied as a function of the twisting, braiding or wrapping process (angle of wrap, tension upon the twisting or wrapping fibers, degree of rotational twisting applied to the fibers per length of precursor, etc.). The offset angle can be arbitrarily chosen to achieve the desired shear properties based upon the particular composite structure, the manufacturing method(s) being employed, and the environment in which the precursor will be utilized.

The present invention provides an improved fiber precursor, and methods for employing such to enhance the structural reinforcement of composite structures. The precursor is comprised of one or more fibrous filaments positioned within the precursor so that the filaments within each fiber are oriented at an angle offset from the axis of the length of the precursor. The offset of these filaments can be accomplished, for example, by twisting a plurality of filaments into a continuous spiral to form the precursor, or by wrapping a collection of colinear filaments about a central core, or by braiding plurality of filaments to form the precursor. The angle of offset at which the twisted, braided or wrapped fibers are positioned can be varied as a function of the twisting, braiding or wrapping process (angle of wrap, tension upon the twisting or wrapping fibers, degree of rotational twisting applied to the fibers per length of precursor, etc.). The offset angle can be arbitrarily chosen to achieve the desired shear properties based upon the particular composite structure, the manufacturing method(s) being employed, and the environment in which the precursor will be utilized.

A process and apparatus for separating a carbon filament tow into a set of reduced filament count bundles. The process includes feeding a tow of carbon filaments into a guide array, mechanically splitting the tow within the guide array into filament bundles, removing a coating from the filament bundles, feeding the filament bundles into a guide pin assembly to separate the filament bundles with a reduced filament count from one another, applying a false twist to the filament bundles to loosen individual filaments then recombining the individual filaments of each filament bundle into a re-bundled ribbon. Coatings may be applied to each re-bundled ribbon prior to winding each re-bundled ribbon onto a take-up.

A process and apparatus for separating a carbon filament tow into a set of reduced filament count bundles. The process includes feeding a tow of carbon filaments into a guide array, mechanically splitting the tow within the guide array into filament bundles, removing a coating from the filament bundles, feeding the filament bundles into a guide pin assembly to separate the filament bundles with a reduced filament count from one another, applying a false twist to the filament bundles to loosen individual filaments then recombining the individual filaments of each filament bundle into a re-bundled ribbon. Coatings may be applied to each re-bundled ribbon prior to winding each re-bundled ribbon onto a take-up.

Disclosed embodiments describe a method for manufacturing a staple fiber based on natural protein fiber. The method may include: providing a protein suspension, the protein suspension comprising fibrils of the natural protein fiber; directing the protein suspension through a nozzle onto a surface for forming a protein based fiber; drying the protein suspension on the surface; extracting the fiber from the surface; and providing the staple fiber. Disclosed embodiments may further describe a fiber based raw wool. The raw wool may include staple fibers, wherein the staple fibers are reconstructed on the basis of protein fibrils and are mechanically subdivided from natural protein fibers, wherein the protein fibrils are interlocked by hydrogen bonds, and wherein the raw wool comprises an unoriented, entangled, fluffy network of staple fibers.

Composite fibers having a structure comprising a core component and sheath component, wherein each of the core component and the sheath component independently include a polymer and a disclosed cooling composition. In various further aspects, this application pertains to single-covered yarn including a core yarn comprising a disclosed composite fiber including a core component and a sheath component, and a first fiber including a cellulosic fiber, such that the first fiber is wrapped or surrounds the core fiber. In still further aspects, this application pertains to a woven or knit fabric including a disclosed single-covered yarn.

Composite fibers having a structure comprising a core component and sheath component, wherein each of the core component and the sheath component independently include a polymer and a disclosed cooling composition. In various further aspects, this application pertains to single-covered yarn including a core yarn comprising a disclosed composite fiber including a core component and a sheath component, and a first fiber including a cellulosic fiber, such that the first fiber is wrapped or surrounds the core fiber. In still further aspects, this application pertains to a woven or knit fabric including a disclosed single-covered yarn.