Jacket material for protection of electrical conductors

• US 5,519,172 A
• Filed: 10/11/1994
• Issued: 05/21/1996
• Est. Priority Date: 09/13/1994
• Status: Expired due to Term

• Current Assignee: W. L. Gore & Associates (W.L. Gore & Associates)
• Original Assignee: W. L. Gore & Associates (W.L. Gore & Associates)
• Inventors: Rubin, Edward, Spencer, Mark S.
• Primary Examiner(s): NIMMO, MORRIS
• Application Number:
  US08/321,634
• Time in Patent Office: 588 Days
• Field of Search: 174/110 R, 174/110 S, 174/110 FC, 174/110 F, 174/110 PM, 174/120 SR, 174/120 AR, 174/36
• US Class Current: 174/110.00R
• CPC Class Codes: H01B 3/44 vinyl resins; acrylic resins silicones H01B3/46
• CPC Class Codes: H01B 3/445 from vinylfluorides or other fluoroethylenic compounds
• CPC Class Codes: H01B 3/46 silicones
• CPC Class Codes: H01B 7/28 Protection against damage caused by moisture, corrosion, chemical attack or weather
• CPC Class Codes: H01B 7/2825 using a water impermeable sheath
• CPC Class Codes: H01B 7/292 using material resistant to heat
• CPC Class Codes: Y02A 30/14 Extreme weather resilient electric power supply systems, e.g. strengthening power lines or underground power cables

Abstract

The present invention is an improved jacketing material for all forms of electro-magnetic energy conductors. The jacket material of the present invention comprises a silicone material that is imbibed into a porous polymer, such as expanded polytetrafluoroethylene, to produce a flexible and durable composite. When applied as a cable jacket, the composite material of the present invention produces dramatic improvement over the use of silicone alone, especially in the areas of load sharing, resistance to fatigue from repeated flexure, and resistance to harsh environmental conditions. The ability of the material of the present invention to withstand repeated autoclave cycles without compromise makes it particularly suitable for cable jacketing in bio-medical applications.

Claims

1. A jacketed conductor comprising

at least one conductor sealed within a jacket, the jacket comprising

a polymeric material including a microporous structure extending between a top and a bottom surface;

and

a silicone filler that fully envelops the microporous structure between the top and bottom surfaces to seal the microporous structure and render it liquid impermeable.

4. The jacketed conductor of claim 1 wherein the jacket is elastic in an axial dimension.

5. The jacketed conductor of claim 4 wherein the jacket is capable of withstanding compression in its axial dimension one dimension of 75 percent with a rebound of at least 50 percent to its original dimensions.

6. The jacketed conductor of claim 1 wherein the jacket is inelastic in a longitudinal dimension so as to load share longitudinal strain between the jacket and the conductor.

7. The jacketed conductor of claim 1 wherein the jacket is capable of withstanding repeated exposure to temperatures in excess of 250 °

C. without significant degradation.

8. The jacketed conductor of claim 7 wherein the jacket is capable of withstanding repeated exposure to harsh chemicals without significant degradation of the jacket and conductor.

9. The jacketed conductor of claim 1 wherein the silicone is selected from the group consisting of methylhydrogen siloxane, dimethylhydrogen siloxane, dimethyl siloxane, dimethylvinyl-terminated siloxane, dimethylmethylphenylmethoxy silicone polymer.

2. The jacketed conductor of claim I wherein the polymeric material comprises a scaffold of polymeric nodes interconnected by fibrils, with the nodes and fibrils enveloped with the silicone.

3. The jacketed conductor of claim 2 wherein the polymeric material comprises expanded polytetrafluoroethylene (PTFE).