Development of Novel Fluoroalkyl End-Capped Gemini Surfactants to Emulsify Fluorinated Oil

点击翻译按钮获取中文摘要

Though perfluorooctanoic acid (PFOA), which is chemically and biologically stable and has excellent surfactant properties, has been widely used as an emulsifier for fluorinated oils, it is now focused on the problem that PFOA remains in human body, living entries, and also in environment. Therefore, the development of novel non-and low-remaining surfactants is necessary for the emulsification of fluorinated oils.In this work, as fluorochemicals having short fluoroalkyl group are known to remain in body only at low level, novel two hydrophile and two lipophile surfactants (Gemini) end-capped with fluoroalkyls were designed and prepared. In 2005-2006, SO3H type Gemini surfactants having various fluoroalkyls were successfully prepared from 1,4-pentadiene via addition of fluoroalkyl radicals as key step. In 2006-2007, a new route to COOH type Gemini surfactants via linking of two fluoroalkyl substituted malonates with several methylene spacers was also established.Their surfactant properties were studied based on the measurements of surface tension and surface pressure-Area curves. They showed excellent power of lowering surface tensions and quite lower critical micellar concentrations by 1〜2 orders in comparison with the corresponding convenient fluorinated surfactants. Moreover, based on the surface pressure-Area measurement, it was indicated that they have a superior ability to adsorb and arrange at the interface and to reduce oil/water interface tension, which will mean that they are promising as an alternative of PFOA. Next, the practical investigation of emulsification of fluorinated oils will be carried out.