Carbon nanotube-elastomer composite material, seal material and sealing material each produced using same, and method for producing carbon nanotube-elastomer composite material

Patent metadata

Field	Value
Publication number	US-10494492-B2
Application number	US-201715681113-A
Country	US
Kind code	B2
Filing date	Aug 18, 2017
Priority date	Feb 19, 2015
Publication date	Dec 3, 2019
Grant date	Dec 3, 2019

Abstract

A carbon nanotube-elastomer composite material according to the present invention is produced by dispersing a carbon nanotube in an elastomer, including a carbon nanotube having a diameter of 20 nm or less, the number of layers of 10 or less, the carbon nanotube being contained in an amount of 0.1 to 20 parts by weight inclusive relative to the total weight of the carbon nanotube and the elastomer, and a continuous network having a Va/V 0 value of 0.5 or more is formed in the elastomer wherein V 0 represents the initial volume of the composite material and Va represents the volume of the structure formed from the remaining carbon nanotubes when the composite material is maintained at a temperature of 400° C. or higher for 6 hours while introducing nitrogen, the elastomer is thermally decomposed and the remaining carbon nanotubes form a structure.

First claim

What is claimed is:

1. A carbon nanotube-elastomer composite material consisting of a carbon nanotube and an elastomer, wherein
the carbon nanotube has a diameter of 20 nm or less and the number of layers of 10 or less, the carbon nanotube is contained in an amount from 0.1 part by weight or more to 20 parts by weight or less relative to the total weight of the carbon nanotube and the elastomer, and
a plurality of the carbon nanotubes constitutes a continuous network having a Va/V 0 value of 0.5 or more in the elastomer wherein V 0 represents the initial volume of the carbon nanotube-elastomer composite material and Va represents the volume of the structure formed from the residual carbon nanotube when the composite material is maintained at a temperature of 400° C. or higher for 6 hours, while introducing nitrogen, the elastomer is thermally decomposed and the residual carbon nanotube form a structure.

2. A carbon nanotube-elastomer composite material dispersing consisting of a carbon nanotube and an elastomer, wherein
a plurality of the carbon nanotubes constitutes a continuous network having a Va/V 0 value of 0.5 or more in the elastomer wherein V 0 represents the initial volume of the carbon nanotube-elastomer composite material and Va represents the volume of the structure formed from the residual carbon nanotubes when the composite material is maintained at a temperature of 400° C. or higher for 6 hours, while introducing nitrogen, the elastomer is thermally decomposed and the residual carbon nanotube form a structure, and
the continuous network has at least one or more peaks in a pore distribution within a range of 1 nm or more to 100 μm or less.

3. The carbon nanotube-elastomer composite material according to claim 1 , wherein the carbon nanotube-elastomer composite material has a tear strength of 5 N/mm or more.

4. The carbon nanotube-elastomer composite material according to claim 1 , wherein an elastic modulus at 100° C. of the carbon nanotube-elastomer composite material is higher by 20% or more than an elastic modulus at 100° C. of an elastomer composite material without containing the carbon nanotube.

5. The carbon nanotube-elastomer composite material according to claim 1 , wherein a variation amount of tensile strength after the carbon nanotube-elastomer composite material has been immersed in methyl isobutyl ketone for 72 hours is 4 MPa or less.

6. The carbon nanotube-elastomer composite material according to claim 1 , wherein a change in Shore A hardness after the carbon nanotube-elastomer composite material has been immersed in gasoline oil (gasoline 85%, ethanol 15%) for 72 hours is 4 or less.

7. The carbon nanotube-elastomer composite material according to claim 1 , wherein a conductivity at the time of applying a strain of 20% to the carbon nanotube-elastomer composite material is located in a range from 50% or more to 150% or less relative to the conductivity at the time of a strain of 0%.

8. The carbon nanotube-elastomer composite material according to claim 1 , wherein a tensile strength in a tensile test (in compliance with JIS K6251) at 20° C. or more to 150° C. or less is 5 MPa or more.

9. The carbon nanotube-elastomer composite material according to claim 1 , wherein a storage modulus at 150° C. is 0.5 MPa or more, with a loss tangent being 0.1 or less.

10. The carbon nanotube-elastomer composite material according to claim 1 , wherein in a range from room temperature to 150° C., a thermal expansion coefficient is 6×10 −4 /K or less.

11. The carbon nanotube-elastomer composite material according to claim 1 , wherein the carbon nanotube-elastomer composite material has a glass transition temperature in a range from −50° C. or more to 10° C. or less.

12. The carbon nanotube-elastomer composite material according to claim 1 , wherein the carbon nanotubes have a specific surface area of 200 m 2 /g or more.

13. The carbon nanotube-elastomer composite material according to claim 2 , wherein the carbon nanotube has a diameter of 20 nm or less.

14. The carbon nanotube-elastomer composite material according to claim 2 , wherein the number of layers of the carbon nanotube is 10 or less.

15. An endless seal material comprising the carbon nanotube-elastomer composite material according to claim 1 , wherein the seal material has an endless shape with the outer shape being continuously formed.

16. A sealing material comprising the carbon nanotube-elastomer composite material according to claim 1 .

Assignees

• Aist

Inventors

• ATA Seisuke
• Hata Kenji
• Tomonoh Shigeki

Classifications

• C08J5/005 Primary

  Reinforced macromolecular compounds with nanosized materials, e.g. nanoparticles, nanofibres, nanotubes, nanowires, nanorods or nanolayered materials · CPC title

• C08J2321/00

  Characterised by the use of unspecified rubbers · CPC title

• C01B2202/06

  Multi-walled nanotubes · CPC title

• C08L101/00

  Compositions of unspecified macromolecular compounds · CPC title

• C01B32/174

  Derivatisation; Solubilisation; Dispersion in solvents · CPC title