Solvent-stable semipermeable composite membranes
US5032282A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 11, 1990 |
| Grant date | Jul 16, 1991 |
| Priority date | — |
| Expiry date | Apr 11, 2010 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D2323/30
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Semipermeable composite membranes which comprise a porous substrate of a homo- or copolymer on the basis of acrylonitrile are provided, which have been cross-linked, and at least two layers of film-forming polymers coated thereon, a first layer of monomeric or polymeric diazonium salts which have been reacted with themselves and with an at least difunctional compound, and a second layer, which is chemically bonded to the first one, of a cross-linked, ionically charged hydrophilic polymer. The membranes show good mechanical, physical and chemical stabilities, preferably solvent stability, and are useful in reverse osmosis and ultrafiltration processes, particularly for desalting solutions of low molecular weight organic compounds.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.