Synthesis and physicochemical characterization of new twin-tailed N-oxide based gemini surfactants.
New gemini surfactants (GSs) constituted by two double alkyl chain (from 7 to 17 methylenic units) N-oxide monovalent surfactants joined by a PEG spacer of different length (from 3 to 21 ethylene glycol units), thus combining the properties of both N-oxide and GS surfactants, were synthetized and characterized. The different hydrophilic/hydrophobic balance of the molecular structure strongly influences the morphology and the electrical features of the aggregates. Despite the zwitterionic nature of the polar head groups, all the aggregates are characterized by positive potential thus suggesting protonation at the interface; however, the extent of protonation was shown to strongly depend on the length of the alkyl chain and of the spacer.
Bordi
Federico
F
Dipartimento di Fisica and INFM-CRS SOFT, Università degli Studi di Roma La Sapienza, Piazzale A. Moro 5, 00185 Roma, Italy.
Cerichelli
Giorgio
G
de Berardinis
Nadia
N
Diociaiuti
Marco
M
Giansanti
Luisa
L
Mancini
Giovanna
G
Sennato
Simona
S