High thermal conductivity materials aligned within resins

• US 8,685,534 B2
• Filed: 01/13/2012
• Issued: 04/01/2014
• 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 David Blackhall, Stevens, Gary, Wood, John William
• Primary Examiner(s): Shosho, Callie
• Assistant Examiner(s): HUANG, CHENG YUAN
• Application Number:
  US13/349,900
• Publication Number:
  US 20120118612A1
• Time in Patent Office: 809 Days
• Field of Search: 428/323
• US Class Current: 428/323
• CPC Class Codes: C08K 2201/016 Additives defined by their aspect ratio
• CPC Class Codes: C08K 3/14 Carbides
• CPC Class Codes: C08K 3/22 of metals
• CPC Class Codes: C08K 3/28 Nitrogen-containing compounds
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles

Abstract

In one embodiment the present invention provides for a high thermal conductivity resin that comprises a host resin matrix 32 a high thermal conductivity filler 30. The high thermal conductivity filler forms a continuous organic-inorganic composite with the host resin matrix, and the fillers have an aspect ratio of between 3-100. The fillers are substantially evenly distributed through the host resin matrix, and are aligned in essentially the same direction. In some embodiments the resins are highly structured resin types.

Claims

1. An impregnated electrical insulating tape comprising:

a backing layer;

a mica paper layer bonded to the backing layer;

a resin comprising high thermal conductivity fillers dispersed therein, the resin impregnated through the mica paper layer and the backing layer;

wherein the high thermal conductivity fillers comprise surface functional groups that are disposed on or grafted to the high thermal conductivity fillers, the high thermal conductivity fillers forming covalent bonds between the fillers and the resin to form an intimate interface between the high thermal conductivity fillers and the resin.

2. The impregnated electrical insulating tape of claim 1, wherein the impregnated electrical insulating tape is effective for electrical environments having a voltage of at least 5 kV.

3. The impregnated electrical insulating tape of claim 1, wherein at least 75% of the high thermal conductivity fillers are aligned within 15 degrees of a common direction.

4. The impregnated electrical insulating tape of claim 1, wherein the high thermal conductivity fillers and molecules of the resin are aligned in concert with one another in the same direction.

5. The impregnated electrical insulating tape of claim 1, wherein the high thermal conductivity fillers have an aspect ratio of between 3-100, and wherein the high thermal conductivity fillers comprise fillers from 1-1000 nm in length.

6. The impregnated electrical insulating tape of claim 1, wherein the surface functional groups are reactively grafted to the high thermal conductivity fillers.

7. The impregnated electrical insulating tape of claim 1, wherein the resin comprises at least one of a liquid crystal thermoset resin or 1,2 vinyl polybutadiene.

8. The impregnated electrical insulating tape of claim 1, wherein the surface functional groups comprise at least one of hydroxyl, carboxylic, amine, epoxide, silane, and vinyl groups, and combinations thereof.

9. The impregnated electrical insulating tape of claim 1, wherein the high thermal conductivity fillers comprise dendrimers.

10. The impregnated electrical insulating tape of claim 9, wherein the dendrimers comprise an organic core with an inorganic shell.

11. The impregnated electrical insulating tape of claim 9, wherein the dendrimers comprise an inorganic core with an organic shell.

12. The impregnated electrical insulating tape of claim 1, wherein the high thermal conductivity fillers comprise at least one member from the group consisting of a diamond like coating, Al₂O₃, AIN, MgO, ZnO, BeO, BN, Si₃N₄, SiC and SiO₂.

13. The impregnated electrical insulating tape of claim 1, wherein the high thermal conductivity fillers comprise hydroxylated boron nitride.

14. An impregnated electrical insulating tape comprising:

a backing layer;

a mica paper layer bonded to the backing layer;

a resin comprising high thermal conductivity fillers dispersed therein, the resin impregnated through the mica paper layer and the backing layer;

wherein the high thermal conductivity fillers comprise surface functional groups that are disposed on or grafted to the high thermal conductivity fillers, the high conductivity fillers forming covalent bonds between the high conductivity fillers and the resin to form an intimate interface between the high thermal conductivity fillers and the resin;

wherein the high thermal conductivity fillers and molecules of the resin are aligned in concert with one another in the same direction; and

wherein at least 75% of the high thermal conductivity fillers are aligned within 15 degrees of a common direction.

15. The impregnated electrical insulating tape of claim 14, wherein the resin comprises at least one of a liquid crystal thermoset resin or 1,2 vinyl polybutadiene.

16. The impregnated electrical insulating tape of claim 14, wherein the surface functional groups comprise at least one of hydroxyl, carboxylic, amine, epoxide, silane, and vinyl groups, and combinations thereof.

17. The impregnated electrical insulating tape of claim 14, wherein the high thermal conductivity fillers comprise dendrimers.

18. A method for electrically insulating an electrical object comprising:

providing a mica tape comprising a mica paper layer bonded to a backing layer;

winding the mica tape around the electrical object;

impregnating the mica tape and the backing layer with a resin comprising high thermal conductivity fillers dispersed therein, wherein the high thermal conductivity fillers comprise surface functional groups that are disposed on or grafted to the high thermal conductivity fillers, the high conductivity fillers forming covalent bonds between the fillers and the resin to form an intimate interface between the high thermal conductivity fillers and the resin;

aligning molecules of the resin and the high thermal conductivity fillers in concert with one another by an external force; and

semi-curing or curing the resin to lock the alignment in position.

19. The method of claim 18, wherein at least 75% of the high thermal conductivity fillers are aligned within 15 degrees of a common direction.

20. The method of claim 18, wherein aligning is done by application of a field selected from the group consisting of a magnetic, an electrical, a mechanical, a sonic, and an ultrasonic field.