INVESTIGADORES
CORREA Nestor Mariano
artículos
Título:
Effect of the cationic surfactant moiety on the structure of water entrapped in two catanionic reverse micelles created from ionic liquid-like surfactants.
Autor/es:
CRISTIAN VILLA; JUANA J. SILBER; N. MARIANO CORREA *; R. DARIO FALCONE
Revista:
Chemphyschem
Editorial:
WILEY-V C H VERLAG GMBH
Referencias:
Lugar: Weinheim; Año: 2014 vol. 15 p. 3097 - 3109
ISSN:
1439-4235
Resumen:
The behavior of water entrapped in reverse micelles (RMs)
formed by two catanionic ionic liquid-like surfactants, benzyln-
hexadecyldimethylammonium 1,4-bis-2-ethylhexylsulfosuccinate
(AOT-BHD) and cetyltrimethylammonium 1,4-bis-2-ethylhexylsulfosuccinate
(AOT-CTA), was investigated by using dynamic
(DLS) and static (SLS) light scattering, FTIR, and 1H NMR
spectroscopy techniques. To the best of our knowledge, this is
the first report in which AOT-CTA has been used to create RMs
and encapsulate water. DLS and SLS results revealed the formation
of RMs in benzene and the interaction of water with
the RM interface. From FTIR and 1H NMR spectroscopy data,
a difference in the magnitude of the water?catanionic surfactant
interaction at the interface is observed. For the AOT-BHD
RMs, a strong water?surfactant interaction can be invoked
whereas for AOT-CTA this interaction seems to be weaker. Consequently,
more water molecules interact with the interface in
AOT-BHD RMs with a completely disrupted hydrogen-bond
network, than in AOT-CTA RMs in which the water structure is
partially preserved. We suggest that the benzyl group present
in the BHD+ moiety in AOT-BHD is responsible for the behavior
of the catanionic interface in comparison with the interface
created in AOT-CTA. These results show that a simple change
in the cationic component in the catanionic surfactant promotes
remarkable changes in the RMs interface with interesting
consequences, in particular when using the systems as
nanoreactors.