Method of making a conductive polymer composition
US5985976A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 12, 1997 |
| Grant date | Nov 16, 1999 |
| Priority date | — |
| Expiry date | Nov 12, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24926
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A conductive polymer composition which has a resistivity at 20.degree. C. of at most 1.0 ohm-cm and a PTC anomaly of at least 104 contains at most 64% by volume of a crystalline polymeric component and at least 36% by volume of a particulate conductive filler. A preferred conductive filler is carbon black having a DBP number of 60 to 120 cm.sup.3 /100 g. Compositions of the invention, as well as other conductive polymer compositions are preferably prepared by a method in which the polymeric component and the filler are blended in a first step at a temperature greater than the melting temperature of the polymer, the mixture is then cooled, and the mixture is then mixed in a second step. The resulting composition has a PTC anomaly that is at least 1.2 times the PTC anomaly of the first mixture.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.