| 초록 |
A polymeric material has garnered increasing interest in various application including membrane-based gas separation processes. Considering that, gas molecules can diffuse through free volume (so as called thermodynamic void) in polymeric films, engineering of thermodynamic void is a key. As a result, many studies have focused mainly on to find a suitable size of thermodynamic void. A general way is to find optimum combinations of chemical structures. Rather than this approach, we here study the gas transport behavior by using physically modified polymers. As a model polymer, a fluorinated polyimides (PI) are used because of its various reaction pathways. Identical chemical structures of the synthesized PI membranes are identified by using FT-IR and 1H-NMR. However, those membranes show individual physical properties such as density, d-spacing, as well as solubility. More interesting is that the prepared PI membranes exhibit totally different gas transport features. |
