Gas transport mechanism in sulfonated polyimides: Consequences on gas selectivity

• Published in: Journal of membrane science Vol. 209; no. 1; pp. 241 - 253
• Main Authors: Piroux, F, Espuche, E, Mercier, R, Pinéri, M, Gebel, G
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-11-2002; Elsevier
• Subjects: Chemical Sciences; Copolymers; Permeation; Polymers; Selectivity; Sorption; Sulfonated polyimides; Sorption; Copolymers; Selectivity; Sulfonated polyimides; Permeation; copolymers; selectivity; sulfonated polyimides; permeation; sorption
• ISSN: 0376-7388; 1873-3123
• DOI: 10.1016/S0376-7388(02)00350-2

Structure–properties relationships in terms of gas transport have been established for a large series of sulfonated copolyimides synthesized with a naphthalenic dianhydride, a sulfonated diamine [SD] and various non-sulfonated diamines. For these two phases systems, a phase inversion has been evidenced for sulfonated block content ranging between 30 and 50%. The contribution of the dispersed sulfonated phase to the gas transport greatly depends on the structure of the non-sulfonated diamine. As a consequence, a large range of permeability values can be obtained varying the nature of the non-sulfonated diamine, the sulfonated diamine content and the sulfonated block length. The diffusion coefficient is in all cases the dominant factor in the transport phenomena and good compromise between O
2/N
2 selectivity and O
2 flux can be achieved with these systems.