High thermal conductivity materials with grafted surface functional groups

• US 20050245644A1
• Filed: 06/14/2005
• Published: 11/03/2005
• Est. Priority Date: 07/11/2003
• Status: Active Grant

• Current Assignee: Siemens Energy Incorporated (Siemens AG)
• Original Assignee: Siemens Westinghouse Power Corporation
• Inventors: Stevens, Gary, Smith, James David Blackhall, Wood, John William
• Granted Patent: US 7,781,063 B2
• Time in Patent Office: Days
• US Class Current: 523/400
• CPC Class Codes: C08J 5/10 characterised by the additives used in the polymer mixture
• CPC Class Codes: C08J 5/241 using inorganic fibres
• CPC Class Codes: C08J 5/244 using glass fibres
• CPC Class Codes: C08J 5/246 using polymer based synthetic fibres
• CPC Class Codes: C08J 5/249 characterised by the additives used in the prepolymer mixture
• CPC Class Codes: C08K 2201/016 Additives defined by their aspect ratio
• CPC Class Codes: C08K 3/14 Carbides
• CPC Class Codes: C08K 3/18 Oxygen-containing compounds, e.g. metal carbonyls
• CPC Class Codes: C08K 3/22 of metals
• CPC Class Codes: C08K 3/28 Nitrogen-containing compounds
• CPC Class Codes: C08K 9/04 Ingredients treated with organic substances treated with macromolecular compounds C08K9/08
• CPC Class Codes: C08L 63/00 Compositions of epoxy resins; Compositions of derivatives of epoxy resins
• CPC Class Codes: D21H 17/33 Synthetic macromolecular compounds
• CPC Class Codes: D21H 17/67 Water-insoluble compounds, e.g. fillers, pigments
• CPC Class Codes: Y10T 428/24994 Fiber embedded in or on the surface of a polymeric matrix
• CPC Class Codes: Y10T 428/31511 Of epoxy ether

Abstract

In one embodiment the present invention provides for high thermal conductivity materials 30 that have surface functional groups grafted thereto. These grafted surface functional groups then form a continuous bond with a host resin matrix 32 that the high thermal conductivity materials 30 are added to.

Claims

1. A continuous high thermal conductivity resin comprising:

a host resin matrix; and

a high thermal conductivity filler;

wherein said high thermal conductivity filler forms a continuous organic-inorganic composite with said host resin matrix via surface functional groups that are grafted to said high thermal conductivity filler and forms covalent linkages with said host resin matrix.

2. The resin of claim 1, wherein said high thermal conductivity fillers are chosen from at least one of oxides, nitrides, carbides and diamond.

3. The resin of claim 1, wherein said high thermal conductivity fillers are from 1-1000 nm in length.

4. The resin of claim 1, wherein said high thermal conductivity fillers have an aspect ratio of between 3-100.

5. The resin of claim 4, wherein said high thermal conductivity fillers have an aspect ratio of between 10-50.

6. The resin of claim 1, wherein said high thermal conductivity resin is impregnated into a porous media.

7. The resin of claim 1, wherein said surface functional groups are chosen from at least one of hydroxyl, carboxylic, amine, epoxide, silane and vinyl groups.

8. A continuous organic-inorganic resin with grafted functional groups bridging the organic-inorganic boundary comprising:

a host resin network; and

inorganic high thermal conductivity fillers evenly dispersed in said host resin network and essentially completely co-reacted with said host resin network;

wherein said high thermal conductivity fillers have a length of between 1-1000 nm and an aspect ratio of 10-50;

wherein said high thermal conductivity fillers are selected from at least one of oxides, nitrides, and carbides;

wherein said high thermal conductivity fillers have surface functional groups that are grafted to said high thermal conductivity fillers and wherein said surface functional groups allow for the essentially complete co-reactivity with said host resin network;

wherein said continuous organic-inorganic resin comprises a maximum of 60% by volume of said high thermal conductivity fillers.

9. The continuous organic-inorganic resin of claim 8, wherein said continuous organic-inorganic resin is impregnated into a porous media.

10. The continuous organic-inorganic resin of claim 8, wherein said at least one of oxides, nitrides, and carbides comprise Al2O3, AlN, MgO, ZnO, BeO, BN, Si3N4, SiC and SiO2 with mixed stoichiometric and non-stoichiometric combinations.

11. The continuous organic-inorganic resin of claim 8, wherein said continuous organic-inorganic resin comprises a maximum of 35% by volume of said high thermal conductivity fillers.

12. The continuous organic-inorganic resin of claim 8, wherein said functional groups comprise at least one of hydroxyl, carboxylic, amine, epoxide, silane and vinyl groups.

13. The continuous organic-inorganic resin of claim 8, wherein said host resin network includes epoxy, polyimide epoxy, polyimide, polyester, polybutadiene, liquid crystal epoxy and cyanate-ester.

14. The continuous organic-inorganic resin of claim 8, wherein said continuous organic-inorganic resin further comprises a cross-linking agent.

15. A method of making a high thermal conductivity resin comprising:

supplying a host resin matrix;

gathering a high thermal conductivity material;

surface treating said high thermal conductivity materials to form reactive surface functional groups in a high energy reaction such that said surface functional groups become grafted to said high thermal conductivity materials;

mixing said treated high thermal conductivity materials with said host resin matrix such that said high thermal conductivity materials are substantially uniformly dispersed within said host resin matrix; and

reacting said surface functional groups that are grafted to said high thermal conductivity materials with said host resin matrix to produce said high thermal conductivity resin;

wherein the amount of said high thermal conductivity materials in said high thermal conductivity resin is a maximum of 60% by volume;

wherein said high energy reaction produces bond strength of between approximately 200-500 kJ/mol.

16. The method of claim 15, further comprising inserting a cross-linking agent.

17. The method of claim 15, wherein said surface functional groups comprise at least one of hydroxyl, carboxylic, amine, epoxide, silane and vinyl groups.

18. The method of claim 15, wherein said high thermal conductivity material comprises at least one of diamonds, AlN, BN, Si3N4, and SiC.

19. The method of claim 15, wherein said high energy reaction comprises one of non-equilibrium plasma radiation, chemical vapor and physical vapor deposition, sputter ion plating, laser beams, electron and ion beam evaporation.