Ion exchange polymer dispersion, process for its production and its use
US7582713B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 7, 2005 |
| Grant date | Sep 1, 2009 |
| Priority date | — |
| Expiry date | Oct 20, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24802
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A thickened ion exchange polymer dispersion is obtained by applying ultrasonic vibration or a shearing force to an ion exchange polymer dispersion having a fluorinated polymer having sulfonic acid groups as an ion exchange polymer uniformly dispersed in a dispersion medium so that the viscosity of the dispersion at 25° C. at a shear rate of 10 (1/s) increases 2-2000 times in a thickening step. When formed into a membrane, the dispersion can forms an ion exchange membrane having a uniform and small thickness, high strength, which is free from cracking and shows constant swelling in water and steam. Further, a layer formed by applying a coating solution containing this dispersion and a catalyst powder comprising catalyst metal particles and a carbon support loaded with the catalyst metal particles to a substrate can be used to prepare a membrane-electrode assembly as a catalyst layer for at least one of the cathode and the anode by providing the catalyst layer adjacently to an ion exchange membrane. Because the catalyst layer is highly strong, has few defects and is excellently smooth, a high-performance membrane-electrode assembly for solid polymer electrolyte fuel cells can be obta…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.