| 초록 |
Here, we report high-flux and plasticization-resistive super-glassy membranes fabricated by thermally crosslinking a blend of polyimide (PI) and ladder-structured polysilsesquioxane (LPSQ). The crosslinked PI/LPSQ showed enhanced CO2 permeability, as well as hardness and reduced modulus compared to the as-cast membrane. Also, it showed plasticization resistance up to a CO2 feed pressure of 22 bar. Furthermore, carbon molecular sieve (CMS) membranes derived from the PI/LPSQ membrane are demonstrated. DFT calculations suggest electron accumulation at SiOx phases of hybrid CMS membranes hinders the diffusion of CH4 compared to N2 due to a larger electron overlap. Elevating the soaking temperature enhanced the N2/CH4 solubility selectivity due to strong repulsive interaction between the newly formed ultramicropores with CH4. As a result, the hybrid CMS membranes showed an excellent single gas and N2/CH4/C2H6 (20/76/4) mixed gas N2/CH4 selectivity (28 and 16, respectively). |
