Conductive jacket

Patent metadata

Field	Value
Publication number	US-9728295-B2
Application number	US-201314411937-A
Country	US
Kind code	B2
Filing date	Aug 30, 2013
Priority date	Aug 31, 2012
Publication date	Aug 8, 2017
Grant date	Aug 8, 2017

Abstract

The present invention relates to a new semiconductive composition, which comprises 50 to 98 weight percentage (wt %) of a polymer blend, 2 to 50 wt % of a conductive filler and 0.05 to 2 wt % of an antioxidant; wherein said polymer blend comprises 10 to 99 wt % of a multimodal high density polyolefin, which high density polyolefin has a density which is from 930 to 970 kg/m 3 and a melt flow rate (MFR2@190° C.) according to ISO 1133 (190° C., 2.16 kg) which is less than 1.6 g/10 min, and 1 to 90 wt % of a thermoplastic elastomer, a process for producing a semiconductive composition, and a semiconductive jacket comprising the semiconductive composition, and a power cable comprising the semiconductive jacket or comprising the semiconductive composition, or use of a semiconductive jacket or a semiconductive composition in, for example, a power cable.

First claim

The invention claimed is:

1. A semiconductive composition, which semiconductive composition comprises 50 to 98 weight percentage (wt %) of a polymer blend, 2 to 50 wt % of a conductive filler and 0.05 to 2 wt % of an antioxidant; wherein said polymer blend comprises 10 to 99 wt % of a multimodal high density polyolefin, which high density polyolefin has a density which is from 930 to 970 kg/m 3 and a melt flow rate (MFR2@190° C.) according to ISO 1133 (190° C., 2.16 kg) which is less than 1.6 g/10 min, and 1 to 90 wt % of a thermoplastic elastomer.

2. A semiconductive composition according to claim 1 , wherein the semiconductive composition comprises 60 to 91 wt % of the polymer blend, 9 to 40 wt % of the conductive filler and 0.1 to 1.0 wt % of the antioxidant; wherein said polymer blend comprises 30 to 90 wt % of the multimodal high density polyolefin and 10 to 70 wt % of the thermoplastic elastomer.

3. A semiconductive composition according to claim 1 , wherein the multimodal high density polyolefin is a bimodal high density polyolefin.

4. A semiconductive composition according to claim 1 , wherein the multimodal high density polyolefin has a melt flow rate (MFR2@190° C.) according to ISO 1133 (190° C., 2.16 kg) which is 1.2 g/10 min or less.

5. A semiconductive composition according to claim 1 , wherein the multimodal high density polyolefin of which Mw is from 500 to 60 kg/mol and Mw/Mn is more than 10.

6. A semiconductive composition according to claim 1 , where the multimodal high density polyolefin comprises a multimodal molecular weight distribution α-olefin polymer mixture.

7. A semiconductive composition according to claim 1 , where the multimodal high density polyolefin comprises ethylene copolymer of at least one chosen from butene, 4-methyl-1-pentene, 1-hexene and 1-octene.

8. A semiconductive composition according to claim 1 , where the multimodal high density polyolefin comprises a mixture of a low-molecular ethylene homopolymer and a high-molecular ethylene copolymer of at least one chosen from butene, 4-methyl-1-pentene, 1-hexene and 1-octene.

9. A semiconductive composition according to claim 1 , wherein the conductive filler has a BET nitrogen surface area (according to ASTM D6556), which is less than 700 m 2 /g or an Iodine number (according to ASTM D1510), which is less than 700 mg/g.

10. A semiconductive composition according claim 1 , which comprises 70 to 90 wt % of a polymer blend, 10 to 30 wt % of a conductive filler and 0.4 to 1.0 wt % of an antioxidant; wherein said polymer blend comprises 45 to 80 wt % of a multimodal high density polyolefin, which high density polyolefin has a melt flow rate (MFR2@190° C.) according to ISO 1133 (190° C., 2.16 kg) which is 0.1 to 1.2 g/10 min, and 20 to 55 wt % of a thermoplastic elastomer, and wherein the conductive filler has a BET nitrogen surface area (according to ASTM D6556), which is 20 to 600 m 2 /g or, alternatively, an Iodine number (according to ASTM D1510), which is 20 to 600 mg/g.

11. A semiconductive composition according to claim 1 , wherein the conductive filler has a BET nitrogen surface area which is less than 300 m 2 /g, or has an Iodine number which is less than 300 mg/g.

12. A semiconductive composition according to claim 1 , wherein the conductive filler has a BET nitrogen surface area which is less than 150 m 2 /g, or has an Iodine number which is less than 150 mg/g.

13. A semiconductive composition according to claim 1 , wherein the conductive filler has a DBP oil absorption (i.e. DBPA) (according to ASTM D 2414), which is less than 320 ml/100 g.

14. A semiconductive composition according to claim 1 , wherein the conductive filler is a carbon black, furnace carbon black, modified furnace carbon black or acetylene carbon black.

15. A semiconductive composition according to claim 1 , wherein the thermoplastic elastomer is an unsaturated polyolefin.

16. A semiconductive composition according to claim 1 , wherein the thermoplastic elastomer is an ethylene alkyl acrylate copolymer, an ethylene ethyl acrylate copolymer, an ethylene butyl acrylate copolymer or an ethylene methyl acrylate copolymer.

17. A semiconductive composition according to claim 1 , where the multimodal high density polyolefine comprises a multimodal molecular weight distribution α-olefin polymer mixture obtained by polymerization of α-olefin in more than two stages, the α-olefin polymer mixture having a density of about 930 to 970 kg/m3 and a melt flow rate (MFR2@190° C.) which is less than 1.6 g/10 min, said α-olefin polymer mixture comprises at least a first and a second α-olefin polymer, of which the first α-olefin polymer has a density of about 930 to 975 kg/m3 and a melt flow rate (MFR2@190° C.) of 50 to 2000 g/10 min, and the density and the melt flow rate of the second α-olefin polymer are chosen so that the resulting α-olefin polymer mixture obtains said density and said melt flow rate.

18. A process for producing a semiconductive composition according to claim 1 , wherein the process comprises mixing conductive filler together with the polymer blend during compounding.

19. A semiconductive jacket comprising the semiconductive composition according to claim 1 .

20. A power cable comprising the semiconductive jacket according to claim 19 .

21. A semiconductive composition according to claim 1 , wherein the conductive filler has a DBP oil absorption (i.e. DBPA) (according to ASTM D 2414), which is less than 250 ml/100 g.

Assignees

• Borealis Ag

Inventors

• Uematsu Takashi
• Svanberg Christer
• Thorn Niklas
• Jager Karl-Michael
• Linder Asa
• Westling Lars

Classifications

• C08L2203/202

  use in electrical wires or wirecoating · CPC title

• C08L23/0869

  with unsaturated acids, e.g. [meth]acrylic acid; with unsaturated esters, e.g. [meth]acrylic acid esters · CPC title

• C08L23/06 Primary

  Polyethylene · CPC title

• C08K5/005

  Stabilisers against oxidation, heat, light, ozone · CPC title

• Y10T428/294

  including metal or compound thereof [excluding glass, ceramic and asbestos] · CPC title