Hollow fibers production method thereof and their applications particularly in the field of membrane-type separations
US4882223A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Oct 30, 1987 |
| Grant date | Nov 21, 1989 |
| Priority date | — |
| Expiry date | Oct 30, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2975
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Non symmetrical hollow fibres presenting a relatively dense layer (`skin`) (H) of a very small thickness (<1 .mu.m) at their outer periphery, which is bound to a so called `open` structure of which the porosity increases in the direction to the inner face; said porous structure comprises microvoids (1) shaped like elongate fingers open to the inside. The invention also relates to the method for obtaining such a symmetrical hollow fibres by known spinning techniques by dry-wet process, by adding to the solution for spinning the polymer in the solvent at least one particular additive and by adding a particular fluid through the hole of the extruded product. Finally, the invention aims at applying the hollow fibres in question to various fields and particularly in ultra-filtration or micro-filtration, in dialysis, reverse osmosis, in gas permeation or pervaporation or they may also be used as supports for liquid membranes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.