Composite membranes and processes using them
US5024765A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 2, 1989 |
| Grant date | Jun 18, 1991 |
| Priority date | — |
| Expiry date | Oct 2, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D2323/30
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A composite membrane which comprises: PA0 (a) a porous semipermeable membrane substrate; and PA0 (b) a coating superimposed thereon which includes at least one member selected from: PA1 monomers containing at least one diazonium group, PA1 polymers containing at least one diazonium group, PA1 monomers containing at least one primary amino group and which have been exposed to the action of at least one member selected from nitrous acid and other reagents which potentially react with primary amine groups to form diazonium groups, and PA1 polymers containing at least one primary amino group and which have been exposed to the action of at least one member selected from nitrous acid and other reagents which potentially react with primary amine groups to form diazonium groups; and wherein the coating has been subjected to at least one in situ chemical reaction with loss of any diazonium groups which may be present, and with formation of valence links in at least one of the modes (i), (ii) and (iii), namely: PA2 (i) among different moieties of the at least one member between themselves; PA1 (ii) between moieties of the at least one member and the material of the substrate; and PA2 (iii) b…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.