Patent · US Expired

Polyimide membranes and their use for gas separation

US4954144A · kind A · utility

24Cited by
12References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 12, 1989
Grant dateSep 4, 1990
Priority date
Expiry dateSep 12, 2009

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08G73/1078
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The present invention is a class of polyimide membranes wherein the diamine portion of the polymer structure is formed from 2,5-di-t-butyl-1,4-phenylenediamine. Membranes formed from polyimides containing this diamine structure exhibit unexpectedly high gas permeability properties and are especially useful for separating oxygen from nitrogen or air.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.