Compositions and electric cables
US6294256A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 8, 1999 |
| Grant date | Sep 25, 2001 |
| Priority date | — |
| Expiry date | Jan 8, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2947
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A composition of matter for use as dielectric shield in an electric power cable having insulation of XLPE, EPR or EPDM comprises: a base polymer which is a copolymer of ethylene with a mono-unsaturated ester; conductive carbon black in an amount to give the composition an electrical resistivity below 500 Am; and as an adhesion-adjusting additive, 1-20% by weight of the base polymer of a copolymer which consists essentially of ethylene and a comonomer having in its molecule at least one carbon-oxygen dipole, said copolymer having a molecular weight less than 20,000 Daltons but a melting point higher than 30.degree. C. This new class of additive permits use of EVA's with lower vinyl acetate content than prior art additives and so enables the composition to have less rubbery physical properties.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.