Aromatic polyimide gas-separating membrane
US4474858A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 1982 |
| Grant date | Oct 2, 1984 |
| Priority date | — |
| Expiry date | Jun 30, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31721
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An aromatic polyimide membrane having an excellent gas-separating property comprises (A) a substrate consisting of a porous membrane comprising at least one aromatic polyimide having at least 80 molar % of at least one type of recurring unit of the formula (I): ##STR1## wherein R is a tetravalent aromatic radical and R.sup.1 is a divalent aromatic radical, the porous membrane exhibiting a hydrogen gas permeability (PH.sub.2) of 1.times.10.sup.-5 to 5.times.10.sup.-1 cm.sup.3 /cm.sup.2.sec.cmHg and a ratio of hydrogen gas permeability (PH.sub.2) to carbon monoxide gas permeability (PCO) of 2 to 5; and (B) 50% or more, based on the weight of the porous membrane substrate, of a gas-separating liquid contained in the porous membrane substrate, the gas-separating liquid being substantially incapable of dissolving therein the porous membrane substrate and having a boiling point of 180.degree. C. or more.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.