J Surfact Deterg
dilute solutions of a dimeric (gemini) surfactant. Langmuir
18:7265–7272
favors fast formation of a stable foam. These preferred
conformations are likely to lead to a parallel orientation of
the alkyl chains of gemini surfactant molecules in the foam
bubbles. With an increase of the spacer lengths (s C 4), the
conformational change of the two long alkyl chains cause a
higher degree of freedom. Concomitant lower interactions
between the alkyl chains of different gemini surfactants
occur and result in a weak and less stable foam.
6. Ulbricht W, Zana R (2001) Alkanediyl-a,x-bis(dimethylalky-
lammonium bromide) surfactants: part 8. Pressure-jump study of
the kinetics of micellar equilibria in aqueous solutions of alka-
nediyl-a,x-bis(dimethyldodecylammonium bromide) surfactants.
Coll Surf A 183–185:487–494
7. Kern F, Lequeux F, Zana R, Candau SJ (1994) Dynamic prop-
erties of salt-free viscoelastic micellar solutions. Langmuir
10:1714–1723
8. Frindi M, Michels B, Levy H, Zana R (1994) Alkanediyl-a,x-
bis(dimethylalkylammonium bromide) surfactants. Part 4. Ultra-
sonic absorption studies of amphiphile exchange between
micelles and bulk phase in aqueous micellar solution. Langmuir
10:1140–1145
9. Zana R (2002) Dimeric (gemini) surfactants: effect of the spacer
group on the association behavior in aqueous solution. J Coll
Interface Sci 248:203–220
10. Groth C, Nyden M, Holmber K, Kanicky JR, Shah DO (2004)
Kinetics of the self-assembly of gemini surfactants. J Surf Deterg
7:247–255
11. Yang QQ, Hong Q, Somasundaran P (2009) 1H NMR study of
micelles formed by mixture of nonionic n-dodecyl-b-D-maltoside
and cationic gemini surfactants. J Mol Liq 146:105–111
12. Manger FM, Keiper JS (2000) Gemini surfactants. Angew Chem
Int Ed 39:1906–1920
Longer spacers (s [ 10) in the gemini surfactants,
however, lead to a slightly decreased CMC and inferior
foamability and foam stability. Here the spacers are long
enough to be in contact with the long alkyl chains, which
likely leads to a completely changed conformational
behavior in aqueous solvents. The CMC is only slightly
reduced, as spacers can be incorporated in the micelles. In
foam bubbles, however, spatial short range order is not as
stable, which likely leads to an even higher degree of
freedom and a distinct decrease of foam stability.
Conclusion
13. Pozniak BP, Kuliszewska E (2013) Competition between sub-
stitution and elimination reaction channels from fragmentation
ratios of diquaternary ammonium bromide and formate ion pairs.
Int J Mass Spectrom 348:29–38
14. Zana R, Benrraou M, Rueff R (1991) Alkenediyl-a,x-bis(dim-
ethylalkylammonium bromide) surfactants. Part 1. Effect of the
spacer chain length on the critical micelle concentration and
micelle ionization degree. Langmuir 7:1072–1075
15. Alami E, Beinert G, Marie P, Zana R (1993) Alkenediyl-a,x-
bis(dimethylalkylammonium bromide) surfactants. Part 3.
Behavior at the air-water interface. Langmuir 9:1465–1467
16. Tehrani-Bagha AR, Holmberg K (2010) Cationic ester-containing
gemini surfactants: physical–chemical properties. Langmuir
26:9276–9282
The foamability and stability of foam correlate directly
with the length of the spacer in the gemini surfactant.
Shorter spacers favor the foam formation and foam sta-
bility. A longer hydrocarbon chain spacer lowers the foam
formation ability and foam stability. The CMC value and
the surface tension were not observed to be a factor in the
foaming ability and foam stability. Conformational aspects
of the gemini surfactants caused by the spacer length are
quite likely to be the main factor of the alteration of
foamability.
17. Laschewsky A, Lunkenheimer K, Rakotoaly RH, Watterbled L
(2005) Spacer effects in dimeric cationic surfactants. Coll Polym
Sci 283:469–479
18. Pinoza A, Perez L, Infante MR, Franses EI (2001) Relation of
foam stability to solution and surface properties of gemini cat-
ionic surfactants derived from arginine. Coll Surf A 189:225–235
Acknowledgments We kindly acknowledge S. Felsinger for
recording NMR measurements and A. Charciarek for performing the
foamability tests.
References
Edyta Kuliszewska graduated in 2003 from Opole University,
Poland, and received her doctorate in 2007 from Vienna University,
Austria. She is a research chemist at the Institute of Heavy Organic
Synthesis ‘‘Blachownia’’, Poland. Her research activities include the
synthesis and characterization of surfactants.
1. Oh SG, Shah DO (1993) The effect of micellar lifetime on the
rate of solubilization and detergency in sodium dodecyl sulfate
solutions. J Am Oil Chem Soc 70:673–678
2. Patist A, Jha BK, Oh SG, Shah DO (1999) Importance of micellar
relaxation time on detergent properties. J Surf Deterg 2:317–324
3. Oh SG, Shah DO (1991) Relationship between micellar lifetime
and foamability of sodium dodecyl sulfate and sodium dodecyl
sulfate/1-hexanol mixtures. Langmuir 7:1316–1318
4. Trzebicka B, Dworak A, Hawranke J, Kuliszewska E, Hord-
yjewicz-Baran Z (2013) Chapter 4: Micellization of Gemini
Surfactants in Aqueous Solutions. In: Bradburn D, Bittinger T
(eds) Micelles: Structural Biochemistry, Formation and Functions
& Usage. Nova Science Publishers, Inc., New York, pp 1–48.
ISBN 978-1-62948-445-7
Lothar Brecker received his diploma and Ph.D. in chemistry from
the University of Dortmund in 1993 and 1996, respectively. After
working at Graz University of Technology and Research Center
Borstel, he became an associate professor at the University of Vienna,
Austria, where he serves as vice head of the Institute of Organic
Chemistry and deputy director of the Chemistry Studies Program. His
main research activities are in the fields of using NMR to study
enzyme ligand binding, interactions between small molecules, and
structural determination of natural products.
5. Oelschlaeger C, Watson G, Candau SJ, Cates ME (2002) Struc-
tural, kinetics, and rheological properties of low ionic strength
123