Fabrication of twisted and non-twisted nanofiber yarns

• US 8,926,933 B2
• Filed: 11/09/2005
• Issued: 01/06/2015
• Est. Priority Date: 11/09/2004
• Status: Active Grant

• Current Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Original Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Inventors: Zhang, Mei, Baughman, Ray H., Atkinson, Kenneth Ross
• Primary Examiner(s): MCCRACKEN, DANIEL
• Application Number:
  US11/718,954
• Publication Number:
  US 20080170982A1
• Time in Patent Office: 3,345 Days
• Field of Search: 4234471- 3, 423/445.B, 977742-754, 977842-848, 428/367
• US Class Current: 423/447.3
• CPC Class Codes: B01L 3/502707 characterised by the manufacture of the container or its components by shaping or joining plastic parts B29C59/00, B29C65/00; by laminating B32B37/00; manufacture of microstructural devices in general B81C
• CPC Class Codes: B29C 48/0019 combined with shaping by flattening, folding or bending
• CPC Class Codes: B32B 18/00 Layered products essentially comprising ceramics, e.g. refractory products
• CPC Class Codes: B32B 2262/106 Carbon fibres, e.g. graphite fibres
• CPC Class Codes: B32B 2307/202 Conductive
• CPC Class Codes: B32B 2310/00 Treatment by energy or chemical effects
• CPC Class Codes: B32B 2313/04 Carbon
• CPC Class Codes: B32B 37/12 characterised by using adhesives
• CPC Class Codes: B32B 5/02 characterised by structural features of a fibrous or filamentary layer layer formed of metallic wires B32B15/02; layer formed of natural mineral fibres B32B19/02; layer formed of wood fibres B32B21/02
• CPC Class Codes: B32B 5/12 characterised by the relative arrangement of fibres or filaments of different layers, e.g. the fibres or filaments being parallel or perpendicular to each other
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: C01B 2202/06 Multi-walled nanotubes
• CPC Class Codes: C01B 2202/08 Aligned nanotubes
• CPC Class Codes: C01B 32/15 Nano-sized carbon materials
• CPC Class Codes: C01B 32/154 Preparation
• CPC Class Codes: C01B 32/158 Carbon nanotubes
• CPC Class Codes: C01B 32/16 Preparation
• CPC Class Codes: C01B 32/164 involving continuous processes
• CPC Class Codes: C01B 32/168 : After-treatment
• CPC Class Codes: C01B 32/17 : Purification
• CPC Class Codes: C01B 32/18 : Nanoonions; Nanoscrolls; Nanohorns; Nanocones; Nanowalls
• CPC Class Codes: C01B 32/36 : Reactivation or regeneration
• CPC Class Codes: C04B 2235/422 : Carbon
• CPC Class Codes: C04B 2235/5248 : Carbon, e.g. graphite
• CPC Class Codes: C04B 2235/526 : characterised by the length of the fibers
• CPC Class Codes: C04B 2235/5264 : characterised by the diameter of the fibers
• CPC Class Codes: C04B 2235/616 : Liquid infiltration of green bodies or pre-forms
• CPC Class Codes: C04B 35/62231 : based on oxide ceramics
• CPC Class Codes: C04B 35/62272 : based on non-oxide ceramics carbon nanotubes C01B32/15; carbon fibers D01F9/12
• CPC Class Codes: C04B 35/62281 : based on silicon carbide C04B35/571 takes precedence
• CPC Class Codes: C04B 35/62855 : Refractory metal oxides
• CPC Class Codes: C04B 35/62892 : with a coating layer consisting of particles
• CPC Class Codes: C04B 35/62897 : Coatings characterised by their thickness
• CPC Class Codes: C04B 35/80 : Fibres, filaments, whiskers, platelets, or the like
• CPC Class Codes: C23C 16/44 : characterised by the method of coating C23C16/04 takes precedence
• CPC Class Codes: C23C 16/50 : using electric discharges generation and control of plasma in discharge tubes for surface treatment H01J37/32, H01J37/34
• CPC Class Codes: D01F 9/08 : of inorganic material working or processing of metal wire B21F; from softened glass, minerals or slags C03B37/00
• CPC Class Codes: D01F 9/12 : Carbon filaments; Apparatus specially adapted for the manufacture thereof
• CPC Class Codes: D01F 9/127 : by thermal decomposition of hydrocarbon gases or vapours or other carbon-containing compounds in the form of gas or vapour, e.g. carbon monoxide, alcohols
• CPC Class Codes: D01F 9/1273 : Alkenes, alkynes
• CPC Class Codes: D01F 9/1275 : Acetylene
• CPC Class Codes: D02G 3/16 : Yarns or threads made from mineral substances
• CPC Class Codes: D02G 3/28 : Doubled, plied, or cabled threads D02G3/32, D02G3/36 take precedence; effect yarns D02G3/34; details of spindles, e.g. bearings D01H7/86
• CPC Class Codes: D02G 3/44 : Yarns or threads characterised by the purpose for which they are designed protective gloves A41D19/00; protective clothing A62B17/00; ropes D07B1/02
• CPC Class Codes: D04H 3/002 : Inorganic yarns or filaments
• CPC Class Codes: D06B 15/00 : Removing liquids, gases or vapours from textile materials in association with treatment of the materials by liquids, gases or vapours
• CPC Class Codes: D06M 15/256 : containing fluorine
• CPC Class Codes: D06M 15/333 : of vinyl acetate; Polyvinylalcohol
• CPC Class Codes: D10B 2101/122 : Nanocarbons
• CPC Class Codes: G01L 1/2287 : constructional details of the strain gauges adjustable resistors H01C10/00
• CPC Class Codes: G02F 1/133308 : Support structures for LCD panels, e.g. frames or bezels
• CPC Class Codes: G02F 1/133334 : Electromagnetic shields
• CPC Class Codes: G02F 1/15165 : Polymers
• CPC Class Codes: H01B 1/24 : the conductive material comprising carbon-silicon compounds, carbon or silicon
• CPC Class Codes: H01B 5/08 : Several wires or the like stranded in the form of a rope
• CPC Class Codes: H01G 11/36 : Nanostructures, e.g. nanofibres, nanotubes or fullerenes
• CPC Class Codes: H01M 10/0565 : Polymeric materials, e.g. gel-type or solid-type
• CPC Class Codes: H01M 4/8605 : Porous electrodes
• CPC Class Codes: H01M 4/926 : on carbon or graphite
• CPC Class Codes: H05K 9/0081 : Electromagnetic shielding materials, e.g. EMI, RFI shielding H05K9/0003 takes precedence
• CPC Class Codes: H10K 30/821 : comprising carbon nanotubes
• CPC Class Codes: H10K 50/30 : Organic light-emitting transistors
• CPC Class Codes: H10K 50/81 : Anodes
• CPC Class Codes: H10K 50/828 : Transparent cathodes, e.g. comprising thin metal layers
• CPC Class Codes: H10K 59/8051 : Anodes
• CPC Class Codes: H10K 59/80524 : Transparent cathodes, e.g. comprising thin metal layers
• CPC Class Codes: H10K 85/221 : Carbon nanotubes
• CPC Class Codes: Y02E 10/549 : Organic PV cells
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02E 60/13 : Energy storage using capacitors
• CPC Class Codes: Y02E 60/50 : Fuel cells
• CPC Class Codes: Y02P 20/133 : Renewable energy sources, e.g. sunlight
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10S 977/742 : Carbon nanotubes, CNTs
• CPC Class Codes: Y10S 977/745 : having a modified surface
• CPC Class Codes: Y10S 977/746 : Modified with biological, organic, or hydrocarbon material
• CPC Class Codes: Y10S 977/752 : Multi-walled
• CPC Class Codes: Y10S 977/843 : Gas phase catalytic growth, i.e. chemical vapor deposition
• CPC Class Codes: Y10S 977/844 : Growth by vaporization or dissociation of carbon source using a high-energy heat source, e.g. electric arc, laser, plasma, e-beam
• CPC Class Codes: Y10S 977/847 : Surface modifications, e.g. functionalization, coating
• CPC Class Codes: Y10S 977/848 : Tube end modifications, e.g. capping, joining, splicing
• CPC Class Codes: Y10S 977/932 : for electronic or optoelectronic application
• CPC Class Codes: Y10S 977/948 : Energy storage/generating using nanostructure, e.g. fuel cell, battery
• CPC Class Codes: Y10S 977/961 : for textile or fabric treatment
• CPC Class Codes: Y10T 428/30 : Self-sustaining carbon mass or layer with impregnant or other layer

Abstract

The present invention is directed to methods of making nanofiber yarns. In some embodiments, the nanotube yarns comprise carbon nanotubes. Particularly, such carbon nanotube yarns of the present invention provide unique properties and property combinations such as extreme toughness, resistance to failure at knots, high electrical and thermal conductivities, high absorption of energy that occurs reversibly, up to 13% strain-to-failure compared with the few percent strain-to-failure of other fibers with similar toughness, very high resistance to creep, retention of strength even when heated in air at 450° C. for one hour, and very high radiation and UV resistance, even when irradiated in air.

Claims

1. A process for producing a yarn comprising nanofibers, the process comprising the steps of:

(a) providing a pre-primary assembly, wherein the pre-primary assembly comprises a forest of substantially parallel nanofibers aligned in a first direction;

(b) drawing laterally from a sidewall of the forest to provide a primary assembly of the nanofibers having an alignment axis extending laterally from the forest about which twisting can occur, wherein the direction of drawing and the alignment axis are at an angle to said first direction of between 60° and

90°

; and

(c) twisting the primary assembly about the alignment axis of said primary assembly to produce a twisted yarn, wherein the primary assembly progressively converges into the twisted yarn as a nanofiber ribbon wedge extending laterally from a wedge base at said sidewall of the forest of substantially parallel nanofibers in the pre-primary assembly.

2. The process of claim 1, wherein the pre-primary assembly is directly formed by chemical synthesis.

3. The process of claim 1, wherein the primary assembly is not a nanofiber yarn.

4. The process of claim 1, wherein a significant component of the nanofibers have a maximum thickness of at most approximately 100 nm.

5. The process of claim 4, wherein a significant component of said nanofibers have a maximum thickness of at most approximately 30 nm.

6. The process of claim 1, wherein a ratio of nanofiber length to twisted yarn circumference is at least approximately 5.

7. The process of claim 6, wherein a significant component of nanofibers in the twisted yarn has a ratio of nanofiber length to twisted yarn circumference that is at least approximately 10.

8. The process of claim 1, wherein a maximum introduced twist in one direction per twisted yarn length for the twisted yarn having a diameter D is at least approximately 0.06/D turns.

9. The process of claim 8, wherein a maximum introduced twist in one direction is at least approximately 0.12/D turns.

10. The process of claim 1, wherein a significant component of the nanofibers have (a) a thickness of at most approximately 100 nm, (b) a length-to-thickness ratio in the thinnest lateral thickness direction of at least approximately 1000, (c) a ratio of nanofiber length to twisted yarn circumference of at least approximately 5, and wherein a maximum introduced twist in one direction per twisted yarn length for the twisted yarn of diameter D is at least approximately 0.06/D turns.

11. The process of claim 1, wherein the primary assembly does not contact any intermediate surface between beginning of the drawing from the pre-primary assembly and beginning of the twisting about the alignment axis.

12. The process of claim 1, wherein the drawing and the twisting are conducted at a temperature between approximately 20°

C. and approximately 500°

C.

13. The process of claim 1, wherein the drawing and the twisting are conducted at a temperature of at most approximately 50°

C.

14. The process of claim 1, wherein at least one of the drawing and the twisting is conducted at an elevated temperature using a heating means selected from the group consisting of

(a) resistive heating of the nanofibers by conducting current along one of the pre-primary assembly, the primary assembly, and the twisted yarn;

(b) the absorption by the nanofibers of electromagnetic radiation from a region selected from the group consisting of visible, ultraviolet, infrared, radio frequency, microwave frequency, and combinations thereof; and

(c) combinations thereof.

15. The process of claim 1, wherein the pre-primary nanofiber assembly has at least approximately orthogonal orientation of the nanofibers with respect to a substrate.

16. The process of claim 15, wherein the pre-primary assembly is on a substrate, and said substrate is substantially non-planar.

17. The process of claim 15, wherein said substrate is sufficiently flexible so as to be processed over rollers.

18. The process of claim 1, wherein the drawing and the twisting are conducted simultaneously to produce the twisted yarn.

19. The process of claim 1, wherein substantially complete conversion from the nanofiber ribbon wedge to partially twisted yarn, having approximately circular cross-section, occurs within about 5 centimeters of the pre-primary assembly.

20. The process of claim 19, wherein the substantially complete conversion from the nanofiber ribbon wedge to partially twisted yarn, having approximately circular cross-section, occurs within about 5 mm of the pre-primary assembly.

21. The process of claim 1, wherein substantially complete conversion from the nanofiber ribbon wedge to partially twisted yarn, having approximately circular cross-section, occurs within about a distance from the forest of nanofibers that is at most about 3 times the width of the region pulled from the forest of nanofibers.

22. The process of claim 1, wherein:

(a) the nanofiber ribbon wedge has a wedge end, a wedge apex, a first lateral wing and a second lateral wing; and

(b) yam core formation appears between about ¼

to about ¾

of the distance from the wedge end to the wedge apex and between about ¼ and

about ¾

of a lateral distance between the first lateral wing and the second lateral wing.

23. The process of claim 1, wherein said primary assembly is densified by:

(a) imbibing a liquid comprising a volatile component; and

(b) subsequently evaporating the volatile component of the liquid.

24. The process of claim 23, wherein said primary assembly is an aerogel.

25. The process of claim 1, wherein:

(a) the primary assembly is an oriented nanofiber ribbon that is obtained by cutting or otherwise forming a nanofiber sheet into ribbon shape;

(b) the nanofibers are aligned predominately in one in-plane sheet direction; and

(c) the ribbon length is along the direction of the alignment.

26. The process of claim 1, wherein the twisted yam is at least a meter long.

27. The process of claim 1, wherein the forest of the substantially parallel nanofibers of the pre-primary assembly is grown on the substrate using a catalyst, wherein the catalyst is formed at least in part by thermal decomposition of a metallo-organic compound during growth of the nanofibers.

28. The process of claim 27, wherein the forest of the substantially parallel nanofibers of the pre-primary assembly is grown on a substrate using a catalyst, wherein the catalyst is formed by a combination of a deposition process before the start of nanofiber growth and thermal decomposition of a metallo-organic compound during growth of the nanofibers.

29. The process of claim 1, wherein the nanofibers comprise single wall carbon nanotubes.

30. The process of claim 1, wherein the pre-primary assembly predominately comprises single wall carbon nanotubes made by chemical vapor deposition.

31. The process of claim 1, wherein twist in one direction is followed by a twist of approximately the same amount in the opposition direction.

32. The process of claim 1, wherein the pre-primary assembly is an aerogel.

33. The process of claim 1, wherein the minimum length-to-thickness ratio of the nanofibers in the thinnest lateral direction is at least approximately 1000.

34. The process of claim 1, wherein the pre-primary assembly is a forest of carbon nanotubes.

35. The process of claim 34, wherein the carbon nanotubes are multiwalled carbon nanotubes having about 10 nm diameter.

36. The process of claim 34, wherein density of the forest is at least 20 billion nanotubes/cm² at the forest base.

37. The process of claim 36, wherein the percentage of area of the forest base that is occupied by the carbon nanotubes is above about 4%.

38. The process of claim 34, wherein product of (i) the number of carbon nanotubes per unit area in the forest and (ii) the carbon nanotube diameter is in the range between 0.16 and 1.6, when measured on the base of the forest.

39. The process of claim 34, wherein at least about 20% of the carbon nanotubes initiated at the base area of the forest extend to essentially the top of the forest.

40. The process or apparatus of claim 34, wherein height of the forest is at least about 50 micron.

41. The process of claim 34, wherein said forest is on a substrate that has a first side and a second side, and forests of the carbon nanotubes are grown on the first side and second side of the substrate.

42. The process of claim 1, wherein (a) the nanofibers comprise multiwalled carbon nanotubes, and (b) the twisted yarn is a multiwalled carbon nanotube yarn.

43. The process of claim 42, wherein the primary assembly is rotated about an axis aligned with the multiwalled carbon nanotube yarn primary axis.

44. The process of claim 1 further comprising producing a plurality of twisted yarns and spinning the plurality of twisted yarns together to produce a multi-strand yarn.

45. The process of claim 1, the forest of nanofibers is supported on a non-planar substrate, and minimum radius of curvature for the occupied area of the forest of nanofibers on said non-planar substrate is at least approximately ten times the maximum height of the forest of nanofibers.

46. The process of claim 1 further comprising applying a yarn enhancing agent, wherein:

(a) said yarn enhancing agent comprises an additive selected from the group consisting of a friction aid, electrolyte, binding agent, a species that enhances yarn thermal conductivity, a species that enhances yarn electrical conductivity, and combinations thereof; and

(b) said yarn enhancing agent is applied to at least one of the pre-primary assembly, the primary assembly, and the twisted yarn.

47. The process of claim 1, wherein the forest of nanofibers is on a growth substrate, and wherein the forest of nanofibers is stripped from the growth substrate and produced into the twisted yarn while not attached to said growth substrate.

48. The process of claim 1, including forming said pre-primary assembly by stripping more than one forest of nanofibers from respective growth substrates stacking the stripped forests upon each other to provide an array of nanofiber forest layers, wherein said pre-primary assembly comprises the array of nanofiber forest layers.

49. The process of claim 1, wherein the forest is synthesized in a furnace growth region on a substrate that continuously moves from the furnace growth region into a region where the nanofibers in the forest are drawn and twisted.

50. The process of claim 1, wherein the pre-primary assembly or the primary assembly comprises a patterned assembly of nanofibers.

51. The process of claim 1, wherein electrical conductivity of the twisted yarn is increased by incorporating an electrically conducting material with the twisted yarn, and wherein the electrically conducting material is selected from the group consisting of conducting polymers, metals, metal alloys, and combinations thereof.

52. The process of claim 1 further comprising wrapping the twisted yarn to form a stored twisted yarn while maintaining said step of drawing and said step of twisting.