A series of perfluorinated cationic surfactants and their corresponding hydrocarbon ones whose general formula is CnX2n+ 1–C (O) NH–(CH2) 3–N+ Me3, I−, with X= F, H and n= 9, 11, have been synthesized via two steps. Their aggregative and surface-active properties were studied in aqueous solution using tensiometry and conductimetry. The critical micelle concentrations and the molecular areas at the air/water interface of fluorinated surfactants ...