High performance cross-linked polybenzoxazole and polybenzothiazole polymer membranes
US8127936B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 2009 |
| Grant date | Mar 6, 2012 |
| Priority date | — |
| Expiry date | Dec 1, 2029 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D2323/345
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
In the present invention high performance cross-linked polybenzoxazole and polybenzothiazole polymer membranes and methods for making and using these membranes have been developed. The cross-linked polybenzoxazole and polybenzothiazole polymer membranes are prepared by: 1) first synthesizing polyimide polymers comprising pendent functional groups (e.g., —OH or —SH) ortho to the heterocyclic imide nitrogen and cross-linkable functional groups in the polymer backbone; 2) fabricating polyimide membranes from these polymers; 3) converting the polyimide membranes to polybenzoxazole or polybenzothiazole membranes by heating under inert atmosphere such as nitrogen or vacuum; and 4) finally converting the membranes to high performance cross-linked polybenzoxazole or polybenzothiazole membranes by a crosslinking treatment, preferably UV radiation. The membranes can be fabricated into any convenient geometry. The high performance cross-linked polybenzoxazole and polybenzothiazole polymer membranes of the present invention are suitable for a variety of liquid, gas, and vapor separations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.