Gas separating membranes from polyimide polymers and a process for using the same
US5045093A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 16, 1990 |
| Grant date | Sep 3, 1991 |
| Priority date | — |
| Expiry date | Oct 16, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G73/1039
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
The present invention is a class of semi-permeable polyimide membranes and a process for using such membranes to separate one or more components of a gaseous mixture. The membranes are prepared from a polyimide having surface-modifiable functionalities comprising repeating units formed from an aromatic dianhydride and a bridged alkylated bisaniline wherein the bridging group of the diamine possesses restricted, rotatable rigid or low Van Der Waal energy substituents which are orthogonal to the polymer backbone. The membranes formed therefrom are contacted in the presence of an oxygen source with an activating force such as high energy electromagnetic irradiation to effect modification of the polymer surface. The surface-modified polyimide membranes exhibit high gas perm-selectivities and are especially useful in effecting the separation of oxygen and nitrogen from air.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.