Insulation paper with high thermal conductivity materials

• US 8,313,832 B2
• Filed: 07/16/2010
• Issued: 11/20/2012
• Est. Priority Date: 06/15/2004
• Status: Expired due to Fees

• Current Assignee: Siemens Energy Incorporated (Siemens AG)
• Original Assignee: Siemens Energy Incorporated (Siemens AG)
• Inventors: Smith, James D, Stevens, Gary, Wood, John W
• Primary Examiner(s): THOMPSON, CAMIE S
• Application Number:
  US12/837,582
• Publication Number:
  US 20100276628A1
• Time in Patent Office: 858 Days
• Field of Search: None
• US Class Current: 428/324
• CPC Class Codes: D21H 13/44 Flakes, e.g. mica, vermiculite
• CPC Class Codes: D21H 17/67 Water-insoluble compounds, e.g. fillers, pigments
• CPC Class Codes: H01B 3/52 wood; paper; press board
• CPC Class Codes: H01B 3/54 hard paper; hard fabrics
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
• CPC Class Codes: Y10T 428/251 Mica
• CPC Class Codes: Y10T 428/256 Heavy metal or aluminum or compound thereof

Abstract

The present invention provides for a high thermal conductivity (HTC) paper that comprises a host matrix, such as mica, and HTC materials intercalated into the host matrix. The HTC materials are comprised of at least one of nanofillers, diamond like coatings directly on the host matrix, and diamond like coatings on the nanofillers.

Claims

1. A structurally stable mica paper comprising:

a host matrix comprising mica flakes defining an electrical insulation layer; and

high thermal conductivity materials intercalated within interstices of the host matrix comprising mica flakes;

wherein the high thermal conductivity materials comprise nanofiller particles, nanofiller particles with diamond like coatings, or combinations thereof, the high thermal conductivity materials comprising an aspect ratio of from 3-100;

wherein the high thermal conductivity materials are disposed within the host matrix in the form of filamentary or dendritic structures so as to achieve a structurally stable discrete two phase composite; and

wherein the structurally stable mica paper is free from resin.

2. The paper of claim 1, wherein the high thermal conductivity materials comprise 0.1-65% by volume of the paper.

3. The paper of claim 2, wherein the high thermal conductivity materials comprise 1-25% by volume of the paper.

4. The paper of claim 1, wherein the resistivity of the paper is about 10¹²- 10¹⁶ Ohm cm.

5. The paper of claim 1, wherein the high thermal conductivity materials are comprised of nanofillers.

6. The paper of claim 1, wherein the high thermal conductivity materials are comprised of nanofillers with diamond like coatings.

7. The paper of claim 1, wherein the paper is combined into an electrical insulation tape.

8. The paper of claim 1, wherein the high thermal conductivity materials have an aspect ratio of from 10-50.

9. The paper of claim 1, wherein the at least one of nanofillers and nanofillers with diamond like coatings have a dimension of from 1-1000 nm.

10. The paper of claim 1, wherein the high thermal conductivity materials are disposed within the host matrix in the form of dendritic structures.

11. The paper of claim 1, wherein the high thermal conductivity materials comprise at least one of silica, alumina, magnesium oxide, silicon carbide, boron nitride, aluminum nitride, zinc oxide, or a diamond material.

12. A high thermal conductivity composite material comprising:

a mixture comprising mica flakelets as a host matrix and high thermal conductivity materials;

wherein the high thermal conductivity materials comprise nanofiller particles, nanofiller particles with diamond like coatings, or combinations thereof;

wherein the high thermal conductivity materials comprise an aspect ratio of from 3-100;

wherein the high thermal conductivity materials are disposed within the host matrix in the form of filamentary or dendritic structures so as to achieve a structurally stable discrete two phase composite; and

wherein the high thermal conductivity composite material is free from resin.

13. The high thermal conductivity composite material of claim 12, wherein the composite material is in the form of a dry solid mixture.

14. The high thermal conductivity composite material of claim 12, wherein the composite material is in the form of a slurry.

15. The high thermal conductivity composite material of claim 12, wherein the composite material is in the form of a structurally stable mica paper.

16. The high thermal conductivity composite material of claim 12, wherein the high thermal conductivity materials comprise at least one of silica, alumina, magnesium oxide, silicon carbide, boron nitride, aluminum nitride, zinc oxide, or a diamond material.