Nanocomposites With Controlled Electrical Properties

• US 20070199729A1
• Filed: 08/20/2004
• Published: 08/30/2007
• Est. Priority Date: 08/21/2003
• Status: Active Grant

• Current Assignee: ABB AB (ABB Limited), Rensselaer Polytechnic Institute
• Original Assignee: ABB AB (ABB Limited)
• Inventors: Hong, Jung-Il, Onneby, Carina, Martensson, Eva, Ma, Dongling, Siegel, Richard, Schadler-Feist, Linda
• Granted Patent: US 7,923,500 B2
• Time in Patent Office: Days
• US Class Current: 174/73.1
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C08K 2201/011 Nanostructured additives
• CPC Class Codes: C08K 3/22 of metals
• CPC Class Codes: H01B 3/004 with conductive additives or conductive layers
• CPC Class Codes: H02G 15/068 connected to the cable shield only H02G15/072 takes precedence
• CPC Class Codes: H02G 15/103 with devices for relieving electrical stress
• CPC Class Codes: H02G 15/105 connected to the cable shield only H02G15/107 takes precedence

Abstract

A field grading material includes a field grading effective amount of a nanoparticle filler distributed in a polymeric matrix, and the nanoparticle filler is heterogeneously distributed in the polymeric matrix.

Claims

14. A field grading material comprising a nanoparticle filler distributed in a polymeric matrix, wherein a surface of said nanoparticle filler is modified by treatment with an organosilane or organotitanate compound and said organosilane compound comprises an organic group selected from alkyl, alkylamino, amino and carboxy.

15. A field grading material according to claim 14, wherein said organic group is selected from methyl, decyl, octyl, vinyl, aminopropyl, and acetoxy.

16. A field grading material comprising a carbon nanotube filler distributed in a polymeric matrix, wherein said filler is heterogeneously distributed in said polymeric matrix and said polymeric matrix comprises a rubber, a thermoplastic polymer, a thermosetting polymer, thermoplastic elastomer, or a crystalline thermoplastic polymer.

17. A field grading material according to claim 16, wherein said polymeric matrix comprises a polymer selected from EPDM and polyethylene.

19. An insulating material comprising an insulating effective amount of a nanoparticle filler distributed in a polymeric matrix, wherein said nanoparticle filler is heterogeneously distributed in said polymeric matrix.

1. A field grading material comprising:

a polymer matrix, said polymer matrix having one or more polymer phases; and

a field grading effective amount of a nanoparticle filler, said filler is;

heterogeneously distributed in said polymer matrix such that said nanoparticle filler is well dispersed in at least part of one of said polymer phases; and

said filler comprises less than 40% by volume of said field grading material.

2. A field grading material according to claim 1, wherein said nanoparticle filler is selected from semiconducting materials having an energy bandgap ranging from 0 eV to 5 eV and dielectric materials having a bulk dielectric constant at infinitely high frequencies of at least 5.

3. A field grading material according to claim 1, wherein said nanoparticle filler comprises a semiconducting material.

4. A field grading material according to claim 1, wherein said nanoparticle filler is selected from ZnO, SnO, InO, CeO, TiO₂, SiC, BaTiO₃, Al₂O₃, SiO₂ and mixtures thereof.

5. A field grading material according to claim 1, wherein said polymeric matrix comprises a rubber, a thermoplastic polymer, a thermosetting polymer, or thermoplastic elastomer.

6. A field grading material according to claim 5, wherein said polymeric matrix comprises at least one of a polyolefin rubber, a thermoplastic polyolefin elastomer/, a silicone rubber, and a crystalline thermoplastic polymer,

7. A field grading material according to claim 5, wherein said polymeric matrix comprises a polymer selected from EPDM and polyethylene.

8. A field grading material according to claim 1, wherein said polymeric matrix comprises a polymer blend of immiscible polymers.

9. A field grading material according to claim 8, wherein said polymer blend is selected from polyethylene/EPDM, LDPE/HDPE, and maleic anhydride-modified EPDM/EPDM.

10. A field grading material according to claim 1, wherein said nanoparticles have a particle size in at least one of a range from 2 to 80 nm, from 5 to 50 nm, and from 5 to 30 nm.

11. A field grading material according to claim 1, wherein said nanoparticle filler comprises less than 40% by volume of the field grading material, less than 30% by volume of the field grading material, or less than 20% by volume of the field grading material.

12. A field grading material according to claim 1, wherein a surface of said nanoparticle filler is modified by treatment with a organosilane or organotitanate compound and the organosilane compound comprises an organic group selected from alkyl, alkylamino, amino and carboxy.

13. A field grading material according to claim 12, wherein said organic group is selected from methyl, decyl, octyl, vinyl, aminopropyl and acetoxy.

18. A method for reducing electric field stress at a joint or termination of an electric cable, said method comprising introducing in said joint or termination a field grading material according to claim 1.

20. An insulating material according to claim 19, wherein said nanoparticle filler is selected from semiconducting materials having an energy bandgap ranging from 0 eV to 5 eV and dielectric materials having a bulk dielectric constant at infinitely high frequencies of at least 5.

21. An insulating material according to claim 19, wherein said nanoparticle filler comprises a semiconducting material.

23. An insulating material according to claim 19, wherein said polymeric matrix comprises a rubber, a thermoplastic polymer, a thermosetting polymers or thermoplastic elastomer.

24. An insulating material according to claim 23, wherein said polymeric matrix comprises at least one of a polyolefin rubber, a thermoplastic polyolefin elastomer, a silicone rubber, and a crystalline thermoplastic polymer.

25. An insulating material according to claim 23, wherein said polymeric matrix comprises a polymer selected from EPDM and polyethylene.

26. An insulating material according to claim 19, wherein said polymeric matrix comprises a polymer blend of immiscible polymers.

27. An insulating material according to claim 26, wherein said polymer blend is selected from polyethylene/EPDM, LDPE/HDPE, and maleic anhydride-modified EPDM/EPDM.

28. An insulating material according to claim 19, wherein said nanoparticles have a particle size in at least one of a range from 2 to 80 nm, from 5 to 50 nm, and from 5 to 30 nm.

29. An insulating material according to claim 19, wherein said nanoparticle filler comprises less than 20% by volume of the insulating material, preferably less than 10% by volume of the insulating material, or less than 5% by volume of the insulating material.

30. An insulating material according to claim 19, wherein a surface of said nanoparticle filler is modified by treatment with an organosilane or organotitanate compound and said organosilane compound comprises an organic group selected from alkyl, alkylamino, amino and carboxy.

31. An insulating material according to claim 30, wherein said organic group is selected from methyl, decyl, octyl, vinyl, aminopropyl and acetoxy.

21-1. An insulating material according to claim 19, wherein said nanoparticle filler is selected from ZnO, SnO, InO, CeO, TiO₂, SiC, BaTiO₃, Al₂O₃, SiO₂ and mixtures thereof.

32. An insulating material comprising a nanoparticle filler distributed in a polymeric matrix, wherein a surface of said nanoparticle filler is modified by treatment with an organosilane or organotitanate compound and the said organosilane compound comprises an organic group selected from alkyl, alkylamino, amino and carboxy.

33. An insulating material according to claim 32, wherein the organic group is selected from methyl, decyl, octyl, vinyl, aminopropyl and acetoxy.

34. An insulating material comprising a carbon nanotube filler distributed in a polymeric matrix, wherein said filler is heterogeneously distributed in said polymeric matrix and said polymeric matrix comprises a rubber, a thermoplastic polymer, a thermosetting polymer, thermoplastic elastomer, or a crystalline thermoplastic polymer.

35. An insulating material according to claim 34 wherein a polymeric matrix comprises a polymer selected from EPDM and polyethylene.

36. A process for manufacturing a field grading material, said process comprising

mixing a nanoparticle filler with at least one polymer to form a mixture, wherein said polymer is in a particulate form, said polymer particulates being at least 10 times greater in size than said nanoparticle filler, and said polymer comprises a rubber, a thermoplastic polymer, a thermosetting polymer, or a thermoplastic elastomer;

and

heating said mixture to form said field grading material.

37. A process according to claim 36, wherein said at least one polymer comprises a mixture of immiscible polymers.

38. A process according to claim 36, wherein said polymer is selected from a group consisting of polyolefin rubber, a thermoplastic polyolefin elastomer, a silicon rubber, and a crystalline thermoplastic polymer.

39. A process according to claim 36, wherein said polymer is selected from EPDM and polyethylene.

40. A process according to claim 36, wherein said polymer particulates are at least 100 times greater in size than the nanoparticle filler.

41. A process according to claim 36, wherein said polymer particulates are at least 1000 time greater in size than the nanoparticle filler.

42. A process according to claim 36, wherein said nanoparticle filler is semiconducting carbon nanotubes.