本研究以聚乙二醇、間苯二甲酸二甲酯磺酸鈉、十八烯酸及十八酸為原料合成一系列Gemini界面活性劑即在其分子構造中加入非離子和陰離子，探討相同為18個碳的油酸和十八酸依結構上的不同以及改變親水基，來觀察其性質之差異性。合成產物以傅立葉紅外線光譜分析儀（FTIR）確認其分子結構，所測試之界面性質包括表面張力、接觸角、乳化粒徑、乳化分層及乳化離心等，並在不同時間下觀察乳化分層來探討合成產物對橄欖油的乳化能力，由測試之結果可顯示其產物具有良好的濕潤性和降低表面張力及界面活性劑分子能有效包覆橄欖油粒子，增加乳化分散性，使乳化液滴穩定分佈。隨時間的變化，乳化粒徑分佈較廣，但仍皆具有良好之乳化能力。

A series of nonionic-anionic Gemini surfactants has been synthesized by the reaction of polyethylene glycol, SIPM, oleic acid and Stearic Acid. Nonionic and anionic moieties had induced into molecular structure. We have studied the differences of hydrophilic chain length. The final products confirmed by Fourier Transform Infrared Spectroscopy (FTIR) and measured interfacial properties include surface tension, contact angle, emulsion particle size, emulsify layer and emulsion centrifugation.At different times to observed emulsion layer. The results indicated these compounds own good wetting and reduce the surface tension. The surfactant molecules can be effectively coated with olive oil particles to increase the emulsifying, so that the emulsion droplets stable distribution. Emulsion particle size distribution wider and emulsion stratification obvious.