Electrodialysis membranes comprising sulfonated constituents
US4738764A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 2, 1986 |
| Grant date | Apr 19, 1988 |
| Priority date | — |
| Expiry date | Jun 2, 2006 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2325/04
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Permselective membranes are disclosed which comprise a layer comprising polystyrene, at least a portion of which is sulfonated, and between about 10 wt. % and about 35 wt. % monovinyl arene-hydrogentated diene block copolymer, at least a portion of which is sulfonated. The membranes exhibit a resistance of less than about 8 .OMEGA.-cm.sup.2 in 7 wt. % Na.sub.2 SO.sub.4 and an ion exchange capacity of between about 1.0 meq/g and about 1.6 meq/g. Monopolar and bipolar membranes comprising the layer are disclosed. A preferred process for forming the membranes comprises the steps of sulfonating polystryene and monovinyl arene-hydrogenated diene block copolymer, forming a mixture of the materials in a solvent, forming a layer of the mixture and drying the layer to form at least a portion of the membrane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.