Electromagnetic shielding composite comprising nanotubes

• US 6,265,466 B1
• Filed: 02/12/1999
• Issued: 07/24/2001
• Est. Priority Date: 02/12/1999
• Status: Expired due to Fees

• Current Assignee: Eikos, Inc.
• Original Assignee: Eikos, Inc.
• Inventors: Conroy, Jeffrey L., Piche, Joseph W., Winsor, Paul, Mack, Patrick, Glatkowski, Paul
• Primary Examiner(s): Cain, Edward J.
• Assistant Examiner(s): WYROZEBSKI LEE, KATARZYNA I
• Application Number:
  US09/250,047
• Time in Patent Office: 893 Days
• Field of Search: 523/137, 428/376, 428/377, 428/378, 428/461, 428/462, 428/460
• US Class Current: 523/137
• CPC Class Codes: G21F 1/10 Organic substances; Dispersions in organic carriers
• CPC Class Codes: Y10S 977/734 Fullerenes, i.e. graphene-based structures, such as nanohorns, nanococoons, nanoscrolls or fullerene-like structures, e.g. WS2 or MoS2 chalcogenide nanotubes, planar C3N4, etc.
• CPC Class Codes: Y10S 977/742 Carbon nanotubes, CNTs
• CPC Class Codes: Y10S 977/753 with polymeric or organic binder
• CPC Class Codes: Y10S 977/788 Of specified organic or carbon-based composition
• CPC Class Codes: Y10S 977/847 Surface modifications, e.g. functionalization, coating
• CPC Class Codes: Y10S 977/902 Specified use of nanostructure

Abstract

An electromagnetic shielding composite having nanotubes and a method of making the same are disclosed. According to one embodiment of the present invention, the composite for providing electromagnetic shielding includes a polymeric material and an effective amount of oriented nanotubes for EM shielding, the nanotubes being oriented when a shearing force is applied to the composite. According to another embodiment of the present invention, the method for making an electromagnetic shielding includes the steps of (1) providing a polymer with an amount of nanotubes, and (2) imparting a shearing force to the polymer and nanotubes to orient the nanotubes.

Claims

1. A composite for providing electromagnetic (EM) shielding, consisting essentially of:

a polymeric material; and

an effective amount of oriented nanotubes for EM shielding, the nanotubes being oriented when a shearing force is applied to the composite.

2. The composite of claim 1, wherein the amount of nanotubes is from about 0.001 to about 15 weight percent of the composite.

3. The composite of claim 1, wherein the amount of nanotubes is from about 0.01 to about 5 weight percent of the composite.

4. The composite of claim 1, wherein the amount of nanotubes is from about 0.1 to about 1.5 weight percent of the composite.

5. The composite of claim 1, wherein the shearing force is applied by elongation.

6. The composite of claim 1, wherein the shearing force is applied by extrusion.

7. The composite of claim 1, wherein the shearing force is applied by injection.

8. The composite of claim 1, wherein the polymeric material is a thermoplastic polymer.

9. The composite of claim 1, wherein the polymeric material is a thermoset polymer.

10. The composition of claim 1, wherein the polymeric material is selected from the group consisting of polyethylene, polypropylene, polyvinyl chloride, styrenic, polyurethane, polyimide, polycarbonate, and polyethylene terephthalate.

11. The composition of claim 1, wherein the composite has a thickness of less than 1 mm.

12. The composite of claim 1, wherein the composite comprises an outer surface of an object.

13. The composite of claim 1, wherein the nanotubes are distributed homogeneously within said polymer.

14. The composite of claim 1, wherein the nanotubes have a length-to-diameter aspect ratio of at least 100:

1.

15. A method for making a electromagnetic (EM) shielding comprising:

providing a polymer with an amount of nanotubes;

imparting a shearing force to the polymer and nanotubes to orient the nanotubes.

16. The method of claim 15, wherein the step of imparting a shearing force to the polymer and nanotubes to orient the nanotubes comprises:

applying an elongation force to the composite.

17. The method of claim 15, wherein the step of imparting a shearing force to the polymer and nanotubes to orient the nanotubes comprises:

applying an extrusion force to the composite.

18. The method of claim 15, wherein the step providing a polymer with an amount of nanotubes comprises:

providing a composite having from about 0.001 to about 15 weight percent of nanotubes.

19. The method of claim 15, wherein the step providing a polymer with an amount of nanotubes comprises:

providing a composite having from about 0.01 to about 5 weight percent of nanotubes.

20. The method of claim 15, wherein the step providing a polymer with an amount of nanotubes comprises:

providing a composite having from about 0.1 to about 1.5 weight percent of nanotubes.

21. The method of claim 15, wherein the polymeric material is a thermoplastic polymer.

22. The method of claim 15, wherein the polymeric material is a thermoset polymer.

23. The method of claim 15, wherein the polymeric material is selected from the group consisting of polyethylene, polypropylene, polyvinyl chloride, styrenic, polyurethane, polyimide, polycarbonate, and polyethylene terephthalate.

24. The method of claim 15, wherein the step of imparting a shearing force to the polymer and nanotubes to orient the nanotubes comprises:

applying an elongation force to the composite.

25. The method of claim 15, wherein the step of imparting a shearing force to the polymer and nanotubes to orient the nanotubes comprises:

applying an extrusion force to the composite.

26. The method of claim 15, wherein the step of imparting a shearing force to the polymer and nanotubes to orient the nanotubes comprises:

applying an injection force to the composite.

27. The method of claim 15, further comprising the step of:

applying the composite to an outer surface of a component.