Semipermeable encapsulated membranes, process for their manufacture and their use
US4778596A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 18, 1986 |
| Grant date | Oct 18, 1988 |
| Priority date | — |
| Expiry date | Aug 18, 2006 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D71/601
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Semipermeable membranes of a porous polymeric substrate whose external and all internal surfaces (pores) are encapsulated by a semipermeable thin film of a hydrophilic polymer are provided. The encapsulating film consists of at least one layer of said polymer which is cross-linked/stabilized by polyfunctional compounds containing at least two functional (reactive) groups. The membrane substrate is optionally pretreated--before the encapsulation step--with polyfunctional compounds. The new membranes can be used in ultrafiltration and reverse osmosis processes. They are solvent-, pressure- and temperature-resistant and show good separation capacities, e.g. for separating organic compounds from salt solutions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.