Process for fabric of continuous graphitic fiber yarns
View Patent ↗Multi-functional and high-performing fabric comprising a first layer of yarns woven to form the fabric wherein the yarns comprise at least one unitary graphene-based continuous graphitic fiber comprising at least 90% by weight of graphene planes that are chemically bonded with one another having an inter-planar spacing d 002 from 0.3354 nm to 0.4 nm as determined by X-ray diffraction and an oxygen content less than 5% by weight. A majority of the graphene planes in such a continuous graphitic fiber are parallel to one another and parallel to a fiber axis direction. The graphitic fiber contains no core-shell structure, has no helically arranged graphene domains or domain boundaries, and has a porosity level less than 5% by volume, more typically less than 2%, and most typically less than 1% (practically pore-free).
1. A process of producing a fabric comprising at least one unitary graphene-based continuous graphitic fiber, said process comprising:
a) preparing a graphene oxide gel in a fluid medium;
b) depositing at least a continuous filament of graphene oxide gel;
c) removing said fluid medium to form a continuous graphene oxide fiber;
d) heat treating said continuous graphene oxide fiber to form a unitary graphene-based continuous fiber;
e) forming a continuous graphitic yarn comprising at least one of said unitary graphene-based continuous fiber; and
f) creating a fabric containing said continuous graphitic yarn;
wherein said unitary graphene-based continuous graphitic fiber has a porosity level less than 5% by volume, an oxygen content less than 5% by weight.
2. The process claim 1 , wherein said depositing step may be conducted via a procedure selected from coating, casting, injection, extrusion, pultrusion, roller, doctor blade, wiper or spinning of the graphene oxide gel onto a solid substrate along a fiber axis direction.
3. The process of producing the fabric comprising at least one unitary graphene-based continuous fiber of claim 1 , wherein said depositing step may be conducted under a condition of mechanical stress.
4. The process claim 1 , wherein said depositing step is onto a substrate.
5. The process of claim 1 , wherein said continuous filament of graphene oxide gel has a cross-section that is circular, elliptical, rectangular, flat-shaped, or hollow.
6. The process claim 1 , where said heat treatment temperature is greater than 600° C.
7. The process of claim 1 , where said heat treatment temperature is greater than 1250° C.
8. The process of claim 1 , where said heat treatment temperature is greater than 2000° C.
9. The process of claim 1 , where said heat treatment takes place in a stress field that includes a local tension stress along a fiber axis direction.
10. The process of claim 1 , where said heat treatment induces chemical merging of individual graphene oxide in an edge-to-edge manner.
11. The process of claim 1 , further comprising chemical functionalization of said graphene oxide, said continuous graphene oxide fiber, or said dried continuous graphene oxide fiber.
12. The process of claim 1 , further comprising a step of combining multiple filaments together to create said continuous graphitic yarn.
13. The process of claim 12 , wherein said continuous graphitic yarn further comprises at least one fiber selected from the group consisting of wool, cotton, asbestos, nylon, synthetic, carbon nanotubes, and graphene-based graphitic fiber.
14. The process of claim 1 , wherein said fabric production step is a weaving process and said unitary graphene-based continuous fiber is contained in at least warp or weft.
15. A fabric made by a process of producing a fabric comprising at least one unitary graphene-based continuous graphitic fiber, said process comprising:
a) preparing a graphene oxide gel in a fluid medium;
b) depositing at least a continuous filament of graphene oxide gel;
c) removing said fluid medium to form a continuous graphene oxide fiber;
d) heat treating said continuous graphene oxide fiber to form a unitary graphene-based continuous fiber;
e) forming a continuous graphitic yarn comprising at least one of said unitary graphene-based continuous fiber; and
f) creating a fabric containing said continuous graphitic yarn;
wherein said unitary graphene-based continuous graphitic fiber has a porosity level less than 5% by volume, an oxygen content less than 5% by weight.
16. The fabric of claim 15 , wherein said fabric has a volumetric packing density greater than 20% and less than 90%.
17. The fabric of claim 15 , wherein said continuous graphitic yarn has a cross-section that is rectangular or flat-shaped, having a width and a thickness.
18. The fabric of claim 17 , wherein said yarn has a width-to-thickness ratio greater than 5.
19. The fabric of claim 15 , wherein said at least one of said unitary graphene-based continuous fibers contains chemical functionalization.
20. The fabric of claim 15 , wherein said fabric is electrically conductive.
21. A heating device containing the fabric of claim 20 , wherein said fabric acts as a resistance heater when an electric current is applied.
22. The fabric of claim 15 , wherein said fabric is configured to block pathogenic agents.