CNT-infused metal fiber materials and process therefor
A composition includes a carbon nanotube (CNT)-infused metal fiber material which includes a metal fiber material of spoolable dimensions, a barrier coating conformally disposed about the metal fiber material, and carbon nanotubes (CNTs) infused to the metal fiber material. A continuous CNT infusion process includes: (a) disposing a barrier coating and a carbon nanotube (CNT)-forming catalyst on a surface of a metal fiber material of spoolable dimensions; and (b) synthesizing carbon nanotubes on the metal fiber material, thereby forming a carbon nanotube-infused metal fiber material.
1. A composition comprising a carbon nanotube (CNT)-infused metal fiber material comprising:
a metal fiber material of spoolable dimensions;
carbon nanotubes (CNTs) infused to said metal fiber material by growing the CNTs in the presence of transition metal nanoparticles;
wherein said CNTs are uniform in length and uniform in distribution; and
a barrier coating conformally disposed about the metal fiber material, the barrier coating separating the metal fiber material from transition metal nanoparticles used for growing the CNTs;
wherein the barrier coating is selected from the group consisting of an alkoxysilane, an alumoxane, spin on glass, and glass nanoparticles.
2. The composition of claim 1 , wherein the infusion of CNTs to the metal fiber material comprises a bonding motif selected from direct bonding of the CNTs to the metal fiber material, indirect bonding via a transition metal nanoparticle catalyst disposed between the CNTs and the metal fiber material, indirect bonding via a transition metal nanoparticle catalyst and barrier coating disposed between the CNTs and the metal fiber material, indirect bonding via the barrier coating disposed between the CNTs and the metal fiber material, and mixtures thereof.
3. The composition of claim 1 , where said CNTs have a length from about 1 micron to about 500 microns.
4. The composition of claim 1 , wherein said CNTs have a length from about 1 micron to about 10 microns.
5. The composition of claim 1 , wherein said CNTs have a length from about 10 microns to about 100 microns.
6. The composition of claim 1 , wherein said CNTs have a length from about 100 microns to about 500 microns.
7. The composition of claim 1 , wherein said uniformity of distribution is characterized by a density up to about 15,000 nanotubes per micron squared (μm 2 ).
8. The composition of claim 1 , wherein said metal fiber material is selected from a metal filament, a metal tow, a metal yarn, a metal tape, a unidirectional metal tape, a metal fiber-braid, a woven metal fabric, a non-woven metal fiber mat, a metal fiber ply, a ribbon, a solid sheet, and a perforated sheet.
9. The composition of claim 1 , wherein said CNTs are selected from the group consisting of single-walled CNTs, double-walled CNTs, multi-walled CNTs, and mixtures thereof.
10. The composition of claim 1 , wherein said CNTs are multi-walled CNTs.
11. The composition of claim 1 further comprising a sizing agent selected from a surfactant, an anti-static agent, a lubricant, siloxanes, alkoxysilanes, aminosilanes, silanes, silanols, polyvinyl alcohol, starch, and mixtures thereof.
12. The composition of claim 1 further comprising a matrix material selected from an epoxy, a polyester, a vinylester, a polyetherimide, a polyetherketoneketone, a polyphthalamide, a polyetherketone, a polyetheretherketone, a polyimide, a phenol-formaldehyde, and a bismaleimide.
13. The composition of claim 1 , wherein the electrical resistivity of said carbon nanotube-infused metal fiber material is lower than the electrical resistivity of said metal fiber material.