| 초록 |
Pyrolytic carbon membranes with attractive separation properties can be prepared by pyrolysis of a polymeric precursors. We synthesize and characterize of a thermally stable metal-containing sulfonated polyimides (M-SPI) based on benzophenone tetracarboxylic dianhydride (BTDA), 4, 4-diamino 2, 2-biphenyl disulfonic acid (BDSA) and meta-phenylenediamine (mPDA). X-ray photoelectron spectroscopy (XPS) was chosen as a tool for confirming metal substitution in sulfonic acid group. Thermogravimetric analysis (TGA) of the M-SPI showed approximately 5% weight loss in the range of 250-350℃ and the final decomposition began at around 500℃. Wide angle X-ray diffraction (WAXD) spectra of M-SPI showed no crystalline behavior, indicating an amorphous structure of the polymer. The gas separation properties of carbon membranes have been investigated by varying pyrolysis conditions such as the pyrolysis temperature, various purge gases and residual oxygen concentration in the purge gas. The membrane pyrolyzed at 600℃ under an argon purge gas show the He. CO2, O2 and N2 permeability of 842, 657, 188 and 26 [Barrer=1×10-10cm3(STP)cm/cm2ScmHg], respectively, and He/N2, CO2/N2 and O2/N2 separation factors of 33, 26 and 7 at 25℃. |
