Microporous polyethylene hollow fibers and process of preparing them
US4020230A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 3, 1975 |
| Grant date | Apr 26, 1977 |
| Priority date | — |
| Expiry date | Oct 3, 1995 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2975
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Normally hydrophobic, polyethylene hollow fibers having contiguous microporosity are prepared by extruding a heated solution of a polyethylene and an ester from a hollow fiber spinnerette, simultaneously cooling and drawing the forming fibers to a ratio of up to 40 to 1, drawing the gelled fibers to an overall ratio of from about 1.5/1 to 800/1 and then removing the ester. The maximum pore radius ranges up to about 50A, and the fibers have gas permeabilities approaching 10.sup.-.sup.2 cc (STP) per cm.sup.2 per second per cm. Hg. transmembrane pressure differential. A significant increase in permeability over polyethylene hollow fibers made according to the teachings of the prior art is achieved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.