Gas Separation Properties of Polyimide Membranes Based on 2,2-Bis(3-amino-4-hydroxyphenyl)hexafluoropropane

Abstract

A series of polyimides (PIs) by thermal imidization of polyamic acid (PAA) were prepared in order to investigate the gas separation property. The single gas permeability of He, H2, CO2, O2, N2 and CH4 were measured and compared in order to determine the effect of the reaction content and thermal imidization temperature on the gas separation properties. The results showed that the higher the thermal imidization temperature is, the more beneficial for the gas separation properties of the PI membranes. The optimum polycondensation reaction content on preparing PI was 25 wt%. The highest ideal selectivity of He/CH4, H2/CH4, CO2/CH4 and H2/N2 is 2814.88, 1652.38, 216.63 and 191.58, respectively.