Synthesis And Performance Of Novel Perfluoropolyether Derivatived Fluorocarbon Surfactants

Fluorocarbon surfactants were widely applied in various industry fields due to their high thermal stability and chemical stability and excellent hydrophobic, oleophobic properties. However, more and more researchers reported that the fluorocarbon surfactants which were composed of perfluoroheptanecarboxylic acid and perfluorooctane sulfonates and their derivatives were toxic to human and environment. So the development of "environmental benign" fluorocarbon surfactants becomes more and more important. The mainly work of this thesis includes two chapters as follow:Part1:Six fluorinated compounds containing sulfonic acid anion or quaternary ammonium were synthesized using oligo(hexafluoropropene oxide)-(HFPO)n as starting material. The structures of products were confirmed by FTIR, NMR and HRMS analyses. Their surface activity, thermal stability, chemical stability, foam property and inorganic salt resistance performance were carefully measured. The results indicate that all these fluorinated compounds have extremely high surface activity and chemical stability. For example, the compound7b can reduce the surface tension of water from72.8mN/m to17.20mN/m, with CMC as low as1×10-4g/mL. The obtained six fluorocarbon surfactants could be applied as substitution of perfluorooctane derivative as Pentadecafluorooctanoic acid, wetting reagent, flatting reagent, foaming reagent and antifouling reagent due to their outstanding surface properties.Part2:Presently, the research about gemini fluorocarbon surfactant containing perfluoropolyether chain is seldom reported in literatures. Starting with (HFPO)n, four new fluorinated compounds11a-b,15and20which have two perfluoropolyether chains were synthesized. Unfortunately, attempts to introduce sulfonic acid group into lla-b,15and20were failed. It is probably due to the weak hydrolysis stability of linkage of perfluoropolyether side chain under the acidic conditions.