Patent ID: 6843829

Claim:
A process for separating component gases of a gas mixture comprising the steps of: a) providing a permeable membrane comprising a polyurethane-polyether or polyurea-polyether block copolymer comprising repeating units of a polymer soft segment of formula (I s ) and a polymer hard segment of formula (I h ): wherein R i of formulae (I s ) and (I h ) is an aliphatic or aromatic radical; s denotes soft; h denotes hard; (PE) of formula (I s ) is a polyether segment; R a of formula (I h ) is a linear or branched aliphatic radical; and X of formula (I h ) is an oxygen atom or —NH—; b) contacting a first side of the membrane with a feed gas mixture; and c) causing a component of said feed gas mixture to selectively permeate through said permeable membrane, thereby forming on a second side of the membrane a permeate composition which has a greater concentration of said component than that of said feed gas mixture.