| 초록 |
Polyimide (PI) membranes have been widely investigated in gas separation applications due to their excellent processability and stabilities. However, it is highly challenging to simultaneously achieve both high gas permeability and a desirable selectivity for PI membranes, limiting their practical use. Herein, we explore the effects of diamine types (i.e. non-fluorinated and fluorinated) in surface properties of a commercial PI (Matrimid®) membrane. Detailed spectroscopic, thermal, and surface analyses indicate that the bulky fluorine groups are responsible for balanced chain packing modes in PI membranes compared to non-fluorinated diamines. As a result, gas permeation tests show that the modified PI membranes with fluorinated diamines exhibit a higher gas permeability and selectivity than those with non-fluorinated ones, especially for a specific gas pair (CO2/CH4). |
