Gas separating membranes formed from blends of polyimide polymers
US5061298A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 13, 1990 |
| Grant date | Oct 29, 1991 |
| Priority date | — |
| Expiry date | Jun 13, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B2210/0046
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
The present invention is a class of semi-permeable polymeric membranes and processes for using such membranes to separate one or more components of a gas mixture. The membranes which are formed from a polymer blend of a first polyimide containing an aromatic diamine and a second polyimide containing an alkenylated diamine having an allyl or allylaryl group exhibit high gas perm-selectivities. The polyimide blends can be surface modified by treatment with an activating force such as high energy electromagnetic irradiation or with a free radical source to impart enhanced selectivity to the membrane without causing a large decrease in composite permeance. These membranes formed from polyimide blends are especially useful in effecting the separation of oxygen and nitrogen from air.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.