Preparation and characterization of asymmetric Kapton membranes for gas separation.

It is a challenge to simultaneously achieve a high selectivity and permeance for the glassy polymeric membranes. Herein, the asymmetric Kapton membrane fabricated by pyromellitic dianhydride and 4,4′-oxydiphenylenediamine was prepared by the phase inversion method and characterized by rheometer, SEM, TGA, FT-IR and tensile testing. The aim of this work is to enhance gas separation performance of the membrane and its application value via optimizing the concentration of acetone additive, coagulation bath composition and evaporation time. After optimizing, results showed that the transition from the instantaneous coagulation to the delayed coagulation, and the inner membrane structure is gradually transferred from the finger-like shape to the sponge-like shape. The optimized gas separation performance of the resulting Kapton membrane has the permeance of 2.49 GPU and 1.10 GPU for H 2 and CO 2 , respectively, as well as selectivity of 57.07 and 25.27 for H 2 /CH 4 and CO 2 /CH 4 , respectively. [Display omitted] • A facile phase inversion method for the fabrication of a high-performance asymmetric Kapton membrane. • A defect-free membrane structure was prepared by the optimization of a series of operation parameters. • A high permeance of 2.49 GPU and 1.10 GPU for H 2 and CO 2 , respectively. • A high selectivity of 57.07 and 25.27 for H 2 /CH 4 and CO 2 /CH 4 , respectively. [ABSTRACT FROM AUTHOR]