近年由於工業化而產出大量之含油廢水，環境污染已成為一個重要問題。聚偏氟乙烯（PVDF）為熱門過濾膜之一，因為其具有化學穩定佳，熱穩定性好及機械強度高等特質。然而PVDF本身之疏水特性使其易受高黏度油污染，降低其重複利用性，大幅縮短過濾膜之壽命。
超樹枝狀高分子（Hyperbranched polymer, HBPs）常作為表面改質劑，其水溶性樹枝狀高分子含有大量的親水性官能基團，及其內部空腔能吸附有機汙染物，在油水分離應領域中極具潛力。
本實驗利用自我縮合反應合成末端羧基化樹枝狀高分子，再藉由偶合劑1,1′-Carbonyldiimidazole (CDI)進行表面改質，通過界面反應將高分子接枝於PVDF纖維膜，因為改質後PVDF膜表面含有大量羧酸基團而具有抗污性質，由實驗結果得到接觸角從131.1°降至0°。濾液中的殘油濃度從1500 ppm降至9.31 ppm，分離效率高達99.4％，並且由於膜表面之羧酸基與陽離子有靜電吸引力，使油水分離膜具有吸附陽離子型界面活性劑之優點，對於陽離子型乳化油較非離子型乳化油有更高的分離效率。

Recently, due to a large amount of industrialization and oily wastewater, environmental pollution has become an important issue. Polyvinylidene fluoride (PVDF) is one of the most popular filtration membranes because of its distinct properties including high chemical resistance, good thermal stability, and extraordinary mechanical properties. While these filtration membranes have favorable separation efficiency and easy processing, the intrinsic hydrophobic characteristic of PVDF makes it susceptible to high-viscosity oil pollution, and thus reducing the lifecycles.
However, the hyperbranched polymers (HBPs) are usually used as a surface modification agent. These structures should offer a high density of functional groups at the membrane surface have large potential such as antifouling property in a variety of oil/water separation applications.
In this work, The carboxylated hyperbranched polymer was synthesized by self-condensation. A electrospun PVDF membrane with antifouling ability was fabricated via an interfacial reaction, using carboxylated HBP and 1,1'-Carbonyldiimidazole (CDI) as modification agent and coupling agent, respectively. The grafted PVDF membrane in combination with the intrinsic hydrophilicity of carboxylic acid-rich groups, the resultant membrane possesses superhydrophilicity while water contact angle decrease from 131.1° to 0°. The oil concentration in permeate decrease from 1500 ppm to 9.31 ppm, the separation efficiency up to 99.4% and the membrane has advantage for capturing cationic surfactant due to the electrostatic interaction.

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