Vésicules de tensioactifs bicaténaires mixtes: caractérisation et stabilité de ces systèmes moléculaires organisés

Abstract The aggregation behaviour in water of 16 ammonium amphiphiles containing one long perfluoroalkyl tail and one long hydrocarbon tail have been studied. Upon sonication, the corresponding vesicular systems were identified by freeze fracture electron microscopy. Their size distribution and mean diameter were investigated by photon correlation spectroscopy (PCS). Long term storage of these systems, showed that their stability is a function of the temperature and of the amphiphilic structure: hydrocarbon chain length and nature of the connector. The crystal to liquid-crystal transition temperature ( T c ) of these systems could not be determined by differential scanning calorimetry (DSC) and light scattering experiments.