Carbon fiber composite material and process for producing the same

• US 7,785,701 B2
• Filed: 04/09/2004
• Issued: 08/31/2010
• Est. Priority Date: 04/09/2003
• Status: Active Grant

• Current Assignee: Hitachi Astemo Ltd. (Hitachi, Ltd.)
• Original Assignee: Nissin Kogyo Company Limited (Hitachi, Ltd.)
• Inventors: Noguchi, Toru, Fukazawa, Shigeru, Shimizu, Shuichi
• Primary Examiner(s): Cole; Elizabeth M
• Application Number:
  US10/821,175
• Publication Number:
  US 20040241440A1
• Time in Patent Office: 2,335 Days
• Field of Search: 428/903, 428/297.4, 428/299.1, 977/778, 977/783
• US Class Current: 428/297.4
• CPC Class Codes: B29C 48/40 using two or more parallel screws or at least two parallel non-intermeshing screws, e.g. twin screw extruders
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C08J 2321/00 Characterised by the use of unspecified rubbers
• CPC Class Codes: C08J 5/005 Reinforced macromolecular compounds with nanosized materials, e.g. nanoparticles, nanofibres, nanotubes, nanowires, nanorods or nanolayered materials
• CPC Class Codes: C08J 5/042 with carbon fibres
• CPC Class Codes: C08K 2201/011 Nanostructured additives
• CPC Class Codes: C08K 7/06 Elements
• CPC Class Codes: C08K 7/24 inorganic
• CPC Class Codes: C08L 21/00 Compositions of unspecified rubbers
• CPC Class Codes: Y10S 428/903 Microfiber, less than 100 micron diameter
• CPC Class Codes: Y10S 977/778 within specified host or matrix material, e.g. nanocomposite films
• CPC Class Codes: Y10S 977/783 Organic host/matrix, e.g. lipid
• CPC Class Codes: Y10T 428/249924 Noninterengaged fiber-containing paper-free web or sheet which is not of specified porosity
• CPC Class Codes: Y10T 428/24994 Fiber embedded in or on the surface of a polymeric matrix
• CPC Class Codes: Y10T 428/249945 Carbon or carbonaceous fiber
• CPC Class Codes: Y10T 428/2913 Rod, strand, filament or fiber

Abstract

The present invention provides a carbon fiber composite material comprising an elastomer and a carbon nanofiber dispersed in the elastomer, wherein the elastomer has an unsaturated bond or a group, having affinity to the carbon nanofiber. Also disclosed is a process for producing the carbon fiber composite material.

Claims

1. A carbon fiber composite material comprising an elastomer and a plurality of carbon nanofibers substantially uniformly dispersed in the elastomer, wherein:

the elastomer has an unsaturated bond or a group, having affinity to the carbon nanofibers;

the elastomer in the composite material is in its uncrosslinked form; and

the composite material has a first spin-spin relaxation time (T2n) of 100 to 3000 μ

sec and a second spin-spin relaxation time (T2nn) of being absent or 1000 to 10,000 μ

sec, and a fraction (fnn) of components having the second spin-spin relaxation time of less than 0.2, as measured under conditions of an observing nucleus of ¹H at 150°

C. by the Hahn-echo method using pulsed NMR technique.

2. The carbon fiber composite material according to claim 1, wherein the elastomer has a weight average molecular weight of 5,000 to 5,000,000.

3. The carbon fiber composite material according to claim 1, wherein the elastomer has, in at least one of its main chain, side chains and terminal chains, at least one member selected from the group consisting of a double bond, a triple bond, a carbonyl group, a carboxyl group, a hydroxyl group, an amino group, a nitrile group, a ketone group, an amide group, an epoxy group, an ester group, a vinyl group, a halogen group, a urethane group, a biuret group, an allophanate group, and a urea group.

4. The carbon fiber composite material according to claim 1, wherein the elastomer in the composite material is one of natural rubber (NR) and nitrile rubber (NBR).

7. The carbon fiber composite material according to claim 1, wherein the elastomer in the composite material is in its uncrosslinked form and the composite material has a flow temperature higher than the inherent flowing temperature of the elastomer by 20°

C. or more.

8. The carbon fiber composite material according to claim 1, wherein each carbon nanofiber has an average diameter of 0.5 to 500 nm.

5. A carbon fiber composite material comprising an elastomer and a plurality of carbon nanofibers substantially uniformly dispersed in the elastomer, wherein the elastomer in the composite material is in its uncrosslinked form, and the composite material has a first spin-spin relaxation time (T2n) of 100 to 3,000 μ

sec and a second spin-spin relaxation time (T2nn) of being absent or 1,000 to 10,000 μ

sec, and a fraction (fnn) of components having the second spin-spin relaxation time of less than 0.2, as measured under conditions of an observing nucleus of ¹H at 150°

C. by the Hahn-echo method using pulsed NMR technique.

9. The carbon fiber composite material according to claim 5, wherein the elastomer in the composite material is in its uncrosslinked form and the composite material has a flow temperature higher than the inherent flowing temperature of the elastomer by 20°

C. or more.

10. The carbon fiber composite material according to claim 5, wherein each carbon nanofiber has an average diameter of 0.5 to 500 nm.

6. A carbon fiber composite material comprising an elastomer and a plurality of carbon nanofibers substantially uniformly dispersed in the elastomer, wherein the elastomer in the composite material is in its crosslinked form, and the composite material has a first spin-spin relaxation time (T2n) of 100 to 2,000 μ

sec and a second spin-spin relaxation time (T2nn) of being absent or 1,000 to 5,000 μ

sec, and a fraction (fnn) of components having the second spin-spin relaxation time of less than 0.2, as measured under conditions of an observing nucleus of ¹H at 150°

C. by the Hahn-echo method using pulsed NMR technique.

11. The carbon fiber composite material according to claim 6, wherein each carbon nanofiber has an average diameter of 0.5 to 500 nm.

12. A carbon fiber composite material comprising an elastomer and a plurality of carbon nanofibers substantially uniformly dispersed in the elastomer, wherein:

the elastomer has an unsaturated bond or a group, having affinity to the carbon nanofibers;

the elastomer in the composite material is in its crosslinked form; and

the composite material has a first spin-spin relaxation time (T2n) of its of 100 to 2,000 μ

sec and a second spin-spin relaxation time (T2nn) of being absent or 1,000 to 10,000 μ

sec, and a fraction (fnn) of components having the second spin-spin relaxation time of less than 0.2, as measured under conditions of an observing nucleus of ¹H at 150°

C. by the Hahn-echo method using pulsed NMR technique.