|Abstract: ||本研究利用高分子摻合技術配合溶劑移除法，製備PVDF或其共聚物之多孔型薄膜，並分析薄膜物性與孔隙結構以評估其應用性。首先將三種氟系高分子：(1)聚偏二氟乙烯(Kynar 740, Elf Ato Chem)，(2)偏二氟乙烯-六氟丙烯共聚物(Kynar 2750)，(3)偏二氟乙烯-四氟乙烯-六氟丙烯三聚物(Kynar 9301)以溶液摻合法，兩兩成對予以混摻，製成複合膜，探討各組成比例對複合膜之相容性，熱性質、結晶性等物性之影響。然後利用適當溶劑與溫度，溶洗出其中之ㄧ成分，以製備多孔型薄膜。藉由混摻比例的不同，預期可製作出不同孔隙結構之對稱或非對稱型薄膜，並以SEM、XRD、Contact Angle等來作膜材物性與結構分析。同時利用水通量與截留分子量之測試來判定薄膜之適用分離程序。|
In this research, polymer blending technique will be incorporated with the solvent leaching method to prepare porous membranes of PVDF or its copolymer. The physical properties of the formed membranes will be characterized and their porous structures be analyzed, such as to find out their suited areas of applications. Firstly, three polymer pairs being chosen from the three fluoro-polymers: (1) poly(vinylidene fluoride) (Kymnar 740, Elf Ato Chem), (2) copolymer of vinylidene fluoride and hexafluoro propylene (Kynar 2750, Elf Ato Chem), (3) terpolymer of vinylidene fluoride, tetrafluoro ethylene, and hexafluoro propylene (Kynar 9301, Elf Ato Chem), will be solution blended to prepare composite membranes. The effect of composition of the blends on the compatibility, level of phase separation, thermo behavior, crystallinity, and mechanical strength of the membranes will be investigated. Thereafter, a suitable solvent will be adopted to extract one polymer component out of the composite at an appropriate temperature to yield a porous membrane. By varying the compositions of the blends, symmetric or asymmetric membranes of a wide spectrum of porous morphology are expected to be produced. SEM, DSC, XRD, DMA, and Contact Angle analyses will be carried out on the formed membranes to obtain the physical and morphological data of the membranes. In addition, water fluxes and molecular weight cut off (MWCO) of the membranes will be determined to judge their applicability in various separation processes.