CNT-infused EMI shielding composite and coating

• US 9,241,433 B2
• Filed: 04/23/2010
• Issued: 01/19/2016
• Est. Priority Date: 04/24/2009
• Status: Active Grant

• Current Assignee: Applied NanoStructured Solutions, LLC (Cabot Corporation)
• Original Assignee: Applied NanoStructured Solutions, LLC (Cabot Corporation)
• Inventors: Shah, Tushar K., Alberding, Mark R., Malecki, Harry C.
• Primary Examiner(s): KARST, DAVID THOMAS
• Application Number:
  US12/766,812
• Publication Number:
  US 20100270069A1
• Time in Patent Office: 2,097 Days
• Field of Search: 523/143
• US Class Current: 1/1
• CPC Class Codes: H01B 1/18 the conductive material comprising carbon-silicon compounds, carbon or silicon
• CPC Class Codes: H01B 1/24 the conductive material comprising carbon-silicon compounds, carbon or silicon
• CPC Class Codes: H01Q 17/002 using short elongated elements as dissipative material, e.g. metallic threads or flake-like particles
• CPC Class Codes: H05K 9/009 comprising electro-conductive fibres, e.g. metal fibres, carbon fibres, metallised textile fibres, electro-conductive mesh, woven, non-woven mat, fleece, cross-linked
• CPC Class Codes: Y10T 428/249924 Noninterengaged fiber-containing paper-free web or sheet which is not of specified porosity

Abstract

A composite for use in electromagnetic interference (EMI) shielding applications includes a carbon nanotube (CNT)-infused fiber material disposed in at least a portion of a matrix material. The composite is capable of absorbing or reflecting EM radiation, or combinations thereof in a frequency range from between about 0.01 MHz to about 18 GHz. The electromagnetic interference (EMI) shielding effectiveness (SE), is in a range from between about 40 decibels (dB) to about 130 dB. A method of manufacturing the composite includes disposing a CNT-infused fiber material in a portion of a matrix material with a controlled orientation of the CNT-infused fiber material within the matrix material, and curing the matrix material. A panel includes the composite and is adaptable to interface with a device for use in EMI shielding applications. The panel is further equipped with an electrical ground.

Claims

1. A composite for use in electromagnetic interference (EMI) shielding applications comprising:

a carbon nanotube (CNT)-infused fiber material disposed in at least a portion of a matrix material, said composite being capable of absorbing electromagnetic (EM) radiation, reflecting EM radiation, or combinations thereof in a frequency range from between about 0.01 MHz to about 18 GHz, wherein the EM shielding capacity of the composite, measured as electromagnetic interference (EMI) shielding effectiveness (SE), is in a range from between about 40 decibels (dB) to about 130 dB, wherein CNTs of the CNT-infused fiber material display a CNT morphology resulting from synthesis of the CNTs directly on the fiber material, the CNT morphology comprising entangled, branched and shared-wall CNTs, and the CNTs extending outwardly from a fiber material comprising the CNT-infused fiber material;

wherein the CNT-infused fiber material has a controlled orientation within the composite.

2. The composite of claim 1 further comprising a plurality of transition metal nanoparticles.

3. The composite of claim 2, wherein said nanoparticles comprise iron.

4. The composite of claim 1, wherein the SE is between about 90 dB to about 110 dB in the radar K-band.

5. The composite of claim 1, wherein the SE is between about 90 dB to about 100 dB in the radar X-band.

6. The composite of claim 1, wherein the SE is between about 80 dB to about 90 dB in the radar C-band.

7. The composite of claim 1, wherein the SE is between about 70 dB to about 80 dB in the radar S-band.

8. The composite of claim 1, wherein the SE is between about 50 dB to about 60 dB in the radar L-band.

9. The composite of claim 1, wherein the CNTs are present in a range between about 1% by weight to about 20% by weight of the composite.

10. The composite of claim 1, wherein the fiber material is selected from the group consisting of glass, carbon, and ceramic.

11. The composite of claim 1, wherein the carbon nanotubes have a length ranging between about 100 microns to about 500 microns.

12. A panel comprising a composite, said composite comprising:

a carbon nanotube (CNT)-infused fiber material disposed in at least a portion of a matrix material, said composite being capable of absorbing electromagnetic (EM) radiation, reflecting EM radiation, or combinations thereof in a frequency range from between about 0.01 MHz to about 18 GHz, wherein the EM shielding capacity of the composite, measured as electromagnetic interference (EMI) shielding effectiveness (SE), is in a range from between about 40 decibels (dB) to about 130 dB, said panel being adaptable to interface with a device for use in EMI shielding applications, wherein said panel is further equipped with an electrical ground, wherein CNTs of the CNT-infused fiber material display a CNT morphology resulting from synthesis of the CNTs directly on the fiber material, the CNT morphology comprising entangled, branched and shared-wall CNTs, and the CNTs extending outwardly from a fiber material comprising the CNT-infused fiber material;

wherein the CNT-infused fiber material has a controlled orientation within the composite.

13. The panel of claim 12, wherein the carbon nanotubes have a length ranging between about 100 microns to about 500 microns.