Co-cast thin film composite flat sheet membranes for gas separations and olefin/paraffin separations

摘要

A co-cast thin film composite flat sheet membrane is provided that comprises an asymmetric porous non-selective support layer with a thickness of 10-50 micrometers and an asymmetric integrally skinned polyimide-containing selective layer with a thickness of 5-40 micrometers on top of said support layer, wherein said asymmetric integrally skinned polyimide-containing selective layer comprises a porous non-selective polyimide-containing support layer with a thickness of ˜5-40 micrometers and a relatively porous, thin, dense, polyimide-containing top skin layer with a thickness of 0.02-0.2 micrometers.