Blend polymer membranes comprising thermally rearranged polymers derived from aromatic polyimides containing ortho-positioned functional groups

摘要

The present invention discloses blend polymer membranes comprising thermally rearranged polymers derived from aromatic polyimides containing ortho-positioned functional groups and methods for making and using these blend polymer membranes. The blend polymer membranes described in the current invention are prepared by heat treatment of blend polymer membranes comprising aromatic polyimides containing ortho-positioned functional groups such as —OH or —SH groups. In some instances, an additional crosslinking step is performed to improve the selectivity of the membrane. These blend polymer membranes have improved flexibility, reduced cost, improved processability, and enhanced selectivity and/or permeability compared to the comparable polymer membranes that comprise a single polymer.