Polymer Membranes Prepared from Aromatic Polyimide Membranes by Thermal Treating and UV Crosslinking

A method for making polymer membranes from aromatic polyimide membranes by thermal treating and UV crosslinking comprising:

• a) first providing or synthesizing a polyimide polymer wherein said polyimide polymer contains pendent —OH or —SH groups ortho to a heterocyclic imide nitrogen and UV cross-linkable functional groups in a polymer backbone;
• b) fabricating polyimide membranes from the polyimide polymer;
• c) heating the polyimide membranes at a temperature between about 300° and 600° C. under inert atmosphere or vacuum for about 30 seconds to one hour to produce a heated polyimide membrane;
• and
• d) exposing said heated polyimide membranes to a crosslinking treatment.

A process for separating at least one gas or liquid from a mixture of gases or liquids using a polymer membrane prepared from an aromatic polyimide membrane by thermal treating and UV crosslinking, said process comprising:

• a) providing a polymer membrane prepared from polyimide polymers comprising cross-linkable functional groups found in a backbone of said cross-linkable polyimide polymers and pendent —OH or —SH groups ortho to a heterocyclic imide nitrogen wherein said polyimide polymers are first subjected to a heat treatment to produce a heat treated polyimide polymer membrane and then said heat treated polyimide polymer membrane is subjected to a crosslinking treatment wherein said polymer membrane prepared from the aromatic polyimide membrane by thermal treating and UV crosslinking is permeable to at least one gas or liquid;
• b) contacting a mixture of gases or liquids on one side of the polymer membrane prepared from the aromatic polyimide membrane by thermal treating and UV crosslinking to cause at least one gas or liquid to permeate the membrane;
• and
• c) removing from an opposite side of the membrane a permeate gas or liquid composition that is a portion of said at least one gas or liquid that permeated the membrane.