Improving CO2 separation performances of Styrene-Butadiene-Styrene Triblock Copolymer Membranes by tunning its Microstructure via varying solvents and/or non-solvents

Microstructure in block copolymers has a critical impact on CO 2 separation performances. In this work, styrene-butadiene-styrene (SBS) triblock copolymer membranes were made using various solvent/non-solvent combinations. It was found that the solvents changed their microstructure thus the CO 2 separation performances were changed accordingly. CO 2 permeability in the range of 203.4 to 282, and CO 2 /N 2 selectivity in the range of 15.8 to 22.7. The highest CO 2 separation performance (P CO2 282 Barrer with CO 2 /N 2 selectivity of 20.5) was obtained using cyclohexane (CYH) as solvent. Furthermore, the CO 2 separation performances of the membrane can be further improved by DI water-induced microstructure rearrangement (P CO2 343.5 Barrer and CO 2 /N 2 selectivity 17.9). In addition, it was found that the rearranged membrane demonstrated stable gas separation performance after the membrane was stored under ambient conditions for about 120 days, clearly denoting that the CO 2 separation performances of block copolymeric membranes can be tuned by varying the solvents/non-solvents.