Porous membrane and production process thereof
US5057218A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 11, 1990 |
| Grant date | Oct 15, 1991 |
| Priority date | — |
| Expiry date | Jul 11, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2333/14
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Disclosed is a porous membrane comprising (1) a hydrophilic copolymer X composed principally of (poly)alkylene glycol mono(meth)acrylate units A and ethylene units B and (2) a polyolefin Y, the (poly)alkylene glycol mono(meth)acrylate units A being of the formula ##STR1## where R.sup.1 and R.sup.2 independently represent hydrogen or methyl, and n has a value in the range of 1 to 9. This porous membrane has permanent hydrophilicy suitable for the treatment of water-based liquids and can be produced by an industrially advantageous process. This process comprises melt-forming a blend of (1) a hydrophilic copolymer X composed principally of (poly)alkylene glycol mono(meth)acrylate units A and ethylene units B and (2) a polyolefin Y; heat-treating the melt-formed product in a vacuum or an inert gas medium at a temperature not higher than the melting point of polyolefin Y for a period of an hour or more; and stretching the heat-treated, melt-formed product to make it porous.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.