9,9’-Bis[4-(4-nitro-3-hydroxyphenoxy)phenyl]fluorine (BAHPPF) and 3,5-diaminobenzoic acid (DABA) with different mole ratios were copolymerized with hexafluorodicarboxylic anhydride (6FDA). After heat treatment, a series of polyimide (PI) and thermal rearrangement (TR) polymer membranes with cross-linked structure were obtained. The experimental results show that with the increase of thermal treatment temperature, the tensile strength and elongation at break of polymer membranes gradually decrease, but the gas permeabilities greatly increases. In addition, the glass transition temperature (Tg) and thermal decomposition temperature of PI membranes are enhanced slightly with the increase of DABA mole ratio. At the same time, the permeabilities of TR membrane materials to H2, CO2, N2, O2 and CH4 are also improved. Among them, the TR-7:3 membrane shows the highest gas permeabilities including H2 of 320.9 Barrer, CO2 of 369.7 Barrer, O2 of 54.3 Barrer, N2 of 15.0 Barrer and CH4 of 11 barrer, respectively. At the same time, the CO2/CH4 selectivities of TR-7:3 and TR-6:4 are 33.6 and 40.6, close to the 2008 Robeson upper bound. Moreover, the O2/N2 separation properties of TR-9:1 and TR-8:2 exceed the 2008 Limit bound.