Single-wall carbon nanotube film having high modulus and conductivity and process for making the same

• US 7,192,642 B2
• Filed: 03/11/2003
• Issued: 03/20/2007
• Est. Priority Date: 03/22/2002
• Status: Expired due to Fees

• Current Assignee: Georgia Tech Research Corporation (University System of Georgia)
• Original Assignee: Georgia Tech Research Corporation (University System of Georgia)
• Inventors: Kumar, Satish, Veedu, Sreekumar T.
• Primary Examiner(s): HENDRICKSON, STUART L
• Application Number:
  US10/386,370
• Publication Number:
  US 20070041887A1
• Time in Patent Office: 1,470 Days
• Field of Search: 423/447.2, 977/DIG.1, 428/367, 428/408, 252/502, 524/495
• US Class Current: 428/367
• 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 2202/02 Single-walled nanotubes
• CPC Class Codes: C01B 32/168 After-treatment
• CPC Class Codes: C03C 17/007 containing a dispersed phase, e.g. particles, fibres or flakes, in a continuous phase
• CPC Class Codes: C03C 2217/475 Inorganic materials
• CPC Class Codes: C03C 25/47 containing particles, fibres or flakes, e.g. in a continuous phase
• CPC Class Codes: C08K 3/04 Carbon
• CPC Class Codes: C09D 1/00 Coating compositions, e.g. paints, varnishes or lacquers, based on inorganic substances
• CPC Class Codes: C09D 5/24 Electrically-conducting paints conductive materials H01B1/00
• CPC Class Codes: C09D 7/61 inorganic
• CPC Class Codes: C09D 7/70 characterised by shape, e.g. fibres, flakes or microspheres
• CPC Class Codes: D06M 11/74 with carbon or graphite; with carbides; with graphitic acids or their salts
• CPC Class Codes: Y10T 428/2918 including free carbon or carbide or therewith [not as steel]
• CPC Class Codes: Y10T 428/30 Self-sustaining carbon mass or layer with impregnant or other layer

Abstract

The invention relates to a film comprising greater than 80 wt % single-wall carbon nanotubes wherein the tensile modulus is at least about 6 GPa at 0.2% strain and the conductivity of the film is at least about 70,000 S/m. The tensile modulus is typically about 8 GPa at 0.2% strain. The method for making the film comprises preparing a solution of single-wall carbon nanotubes in a superacid, such as oleum containing approximately 20 to 30% sulfur trioxide, under a dry, oxygen-free atmosphere. The solution is placed on a surface in a moisture-containing atmosphere, wherein the solution absorbs moisture and acid leaches out. The film is washed to further remove acid, dried, and, optionally, subjected to a heat treatment. Besides free-standing films, coatings of single-wall carbon nanotubes can be made on a variety of surfaces including polymers, glass, metals, and ceramics. The surfaces can be flat planes, fibers or contour shapes.

Claims

1. A film comprising at least about 80 wt % single-wall carbon nanotubes, wherein the film has a tensile modulus of at least about 6 GPa at 0.2% strain, wherein the film is on a substrate, and wherein the substrate is a fiber.

2. The film of claim 1 wherein the fiber comprises a material selected from the group consisting of polyethylene, glass, metal and combinations thereof.