RESUMO
An easy synthetic procedure in two or three steps from perfluoroalkylethyl iodide derivatives led to six novel fluorinated carboxylates monomeric and gemini surfactants with one or two hydrophobic tails, respectively: RF(C2H4)CH(CO2(-))2,2Na(+) and [RF(C2H4)]2C(CO2(-)),Na(+), where RF = C4F9, C6F13, and C8F17. These anionic surfactants exhibited very low surface tension from 15 to 33 mN/m as well as low critical micelle concentration until 1.3 × 10(-4) mol/L. Furthermore, the surface properties of the gemini compound with two short fluoroalkyl chains (RF = C4F9) were found to be almost equal to those of the monomeric surfactant with one long fluoroalkyl chain (RF = C8F17), which could provide an interesting alternative to the bioaccumulative long-chain perfluorinated surfactant.
RESUMO
A rapid synthetic procedure in two steps from perfluoroalkylethyl iodide derivatives led to 18 novel ammonium type hybrid surfactants of the general formula: R(F)(CH(2))(2)S(CH(2))(2)N(+)(CH(3))(2)R(H)Br(-) (R(F) = C(4)F(9), C(6)F(13), C(8)F(17); R(H) = C(4)H(9), C(6)H(13), C(8)H(17), C(10)H(21), C(12)H(25), C(14)H(29)). These hybrid surfactants exhibited very low surface tension (from 16 to 25 mN/m) as well as low critical micellar concentration until 1.5 × 10(-5) mol/L. A special focus was made on aggregation phenomenon as giant multilamellar "brainlike" vesicles were observed via cryogenic scanning electron microscopy (cryoSEM) and transmission electron microscopy (TEM; with a contrast agent) suggesting a high encapsulation ability and a very important specific surface of these particular organizations.