| 초록 |
The hollow fiber membranes were prepared via hybrid process of the thermally induced phase separation(TIPS) and the non-solvent induced phase separation(NIPS). Hybrid process can be operated in the low temperature and induce various phase separation mechanism by cooling as well as solvent/nonsolvent exchange. The spinning dope solution consisted of poly(vinylidene fluoride) (PVDF) / dibutyl phthalate (DBP) / 1-methyl-2-pyrrolidone (NMP), where DBP was used as a diluent and NMP as a solvent for PVDF. Various bore fluids were tested such as nitrogen and different ratio NMP/DBP mixture and NMP/water mixture. Depending on the miscibility of dope solution and internal coagulant the samples underwent the different phase separation mechanisms and rates. Phase separation mechanism study for various combinations were performed to support the interpretation of the membrane structure. Membrane characterizations were performed such as water flux, porosity, pore size, and mechanical strength. |
