Methods for arranging nanoscopic elements within networks, fabrics, and films
View Patent ↗A method for arranging nanotube elements within nanotube fabric layers and films is disclosed. A directional force is applied over a nanotube fabric layer to render the fabric layer into an ordered network of nanotube elements. That is, a network of nanotube elements drawn together along their sidewalls and substantially oriented in a uniform direction. In some embodiments this directional force is applied by rolling a cylindrical element over the fabric layer. In other embodiments this directional force is applied by passing a rubbing material over the surface of a nanotube fabric layer. In other embodiments this directional force is applied by running a polishing material over the nanotube fabric layer for a predetermined time. Exemplary rolling, rubbing, and polishing apparatuses are also disclosed.
1. A method for arranging nanotube elements within a nanotube fabric, comprising:
providing a plurality of nanotube elements over a material layer, to obtain a substantially dry fully formed, fixed nanotube fabric comprising a plurality of nanotube elements in a first operation, wherein said nanotube fabric is substantially free of any suspension medium; and
translating a directional force across at least a portion of said substantially dry fully formed, fixed nanotube fabric in a second operation to arrange at least a portion of said nanotube elements within said nanotube fabric into an ordered network;
wherein said second operation is performed subsequent to said first operation.
2. The method of claim 1 wherein said directional force is applied over said portion of said nanotube fabric at least once.
3. The method of claim 1 wherein said directional force is applied along a single direction.
4. The method of claim 1 wherein said directional force is applied along an arcing direction.
5. The method of claim 1 further comprising repeatedly applying said directional force to said portion of said nanotube fabric.
6. The method of claim 5 wherein said repeated application of said directional force follows a fixed path across said nanotube fabric.
7. The method of claim 1 wherein said material layer is rigid.
8. The method of claim 7 wherein said material layer is selected from a group consisting of elemental silicon, silicon oxide, silicon nitride, silicon carbides, PTFE, organic polymers, pvc, styrenes, polyvinyl alcohol, polyvinyl acetate, hydrocarbon polymers, inorganic backbone, boron nitride, gallium arsenide, group III/V compounds, group II/VI compounds, wood, metals, metal alloys, metal oxides, ceramics, and glass.
9. The method of claim 1 wherein said material layer is a rigid structural composite.
10. The method of claim 1 wherein said material layer is flexible.
11. The method of claim 10 wherein said material is selected from a group consisting of polyethylene terephthalate (PET), polymethylmethacrylate, polyamides, polysulfones, and polycyclic olefins.
12. The method of claim 1 wherein applying said directional force arranges at least a portion of said nanotube elements into a preselected orientation within at least one preselected region of said nanotube fabric.
13. The method of claim 1 further comprising depositing a lubricating medium over a portion of said nanotube fabric prior to said application of said directional force.
14. The method of claim 13 wherein said lubricating medium is comprised of at least one material selected from the list consisting of water, halocarbon liquids, liquefied gases, hydrocarbon liquids, functionalized organic liquids, organo-siloxane based cyclics, linear liquids, molybdenum disulfide, boron nitride, graphite, and styrene beads.
15. The method of claim 1 wherein said nanotube fabric is formed via one of a spin coating operation, a spray coating operation, a dip coating operation, a silk screen printing operation, or a gravure printing operation.
16. The method of claim 1 wherein said nanotube elements are carbon nanotubes.
17. The method of claim 1 wherein said nanotube fabric is a composite mixture of carbon nanotubes and other materials.
18. The method of claim 17 wherein said other materials are selected from the group consisting of buckyballs, amorphous carbon, silver nanotubes, quantum dots, colloidal silver, monodisperse polystyrene beads, and silica particles.
19. The method of claim 1 wherein said nanotube elements are functionalized carbon nanotubes.
20. The method of claim 19 wherein said functionalized carbon nanotubes are carbon nanotubes affixed with moieties which provide an electrically insulating barrier over the sidewalls of said carbon nanotubes.
21. The method of claim 20 wherein said moieties are organic functional groups.
22. The method of claim 20 wherein said moieties are silicon functional groups.
23. The method of claim 20 wherein said moieties include at least one of organosilicate, silicon oxide, organo silicon oxide, methylsilsequioxane, hydrogen silsequioxane, organosiloxane, dimethylsiloxane/polyorgano ether, organopolymer, DNA, and polyamide.
24. The method of claim 1 wherein said directional force is applied through a rubbing element.
25. The method of claim 24 wherein said rubbing element comprises at least one material selected from the group consisting of elemental silicon, polytetrafluoroethylene (PTFE), cellulose acetate, cellulose (e.g., rayon), polyesters, polyamides (e.g., nylons), polymeric materials, and a semi-rigid slurries of starch and water.
26. The method of claim 1 wherein said directional force is applied through a polishing element.
27. The method of claim 26 wherein said polishing element in rotated within a plane parallel to said nanotube fabric layer.
28. The method of claim 26 wherein said polishing element comprises at least one of polyester microfiber, polyamide microfiber, polyester, polyamide, styrene, polyvinylalcohol foam, cotton, wool, cellulose, and rayon.
29. The method of claim 1 wherein said directional force is applied by rolling a cylindrical element over said nanotube fabric layer.
30. The method of claim 29 wherein said cylindrical element comprises a material selected from the group consisting of iron, cobalt, nickel, zinc, tungsten, chromium, manganese, magnesium, titanium, aluminum, steel, rubber, plastic, polystyrene, melamine, silicone, polycarbonate, polyethylene, porcelain, silicon oxide, alumina, silicon carbide, and wood.
31. The method of claim 1 wherein said directional force is applied through a cryokinetic spray.
32. The method of claim 31 wherein said cryokinetic spray comprises one of carbon dioxide (CO 2 ) and argon (Ar).
33. The method of claim 31 wherein said cryokinetic spray is translated across said nanotube fabric layer in a linear direction.
34. The method of claim 1 wherein said directional force is applied within a roll-to-roll process.
35. The method of claim 1 wherein said directional force is applied directly to said nanotube fabric.
36. The method of claim 1 wherein said directional force is applied to said nanotube fabric through an intervening material.
37. The method of claim 1 wherein said ordered network is substantially free of gaps and voids.