POLYMIDE GAS SEPARATION MEMBRANE AND GAS SEPARATION METHOD

摘要

A gas separation membrane made of an aromatic polyimide which is prepared from a tetracarboxylic acid component consisting of a tetracarboxylic acid containing an aromatic ring and a diamine component comprising 90 to 10mol% of a mixture of 3,4'-diaminodiphenyl ether (B1) and 4,4'-diaminodiphenyl ether (B2) and 10 to 90mol% of other aromatic diamine at a B1/B2 molar ratio of 10/1 to 1/10; and a method for gas separation by separating and recovering at least one organic vapor from an organic vapor mixture by the use of the membrane.