10.1021/acs.jpcb.5b01206.s001
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Fegyver
Róbert Mészáros
Róbert
Mészáros
Complexation between Sodium Poly(styrenesulfonate)
and Alkyltrimethylammonium Bromides in the Presence of Dodecyl Maltoside
American Chemical Society
2015
CTAB
surfactant
amphiphile
PSS
cationic
alkyl chain length
C 12G concentration
binding
dodecyl maltoside
DTAB
2015-04-23 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Complexation_between_Sodium_Poly_styrenesulfonate_and_Alkyltrimethylammonium_Bromides_in_the_Presence_of_Dodecyl_Maltoside/2173819
In the present paper, the impact
of dodecyl maltoside (C<sub>12</sub>G<sub>2</sub>) on the association
of sodium poly(styrenesulfonate)
(PSS) with dodecyl- and hexadecyltrimethylammonium bromides (DTAB
and CTAB) was studied. A low amount of nonionic surfactant enhances
the binding of the investigated cationic amphiphiles on PSS, reducing
the cationic surfactant-to-polyanion ratio needed for charge neutralization
and precipitation. This effect is more pronounced for DTAB than for
CTAB due to the considerably higher free surfactant concentration
of the former cationic amphiphile. The synergistic surfactant binding
also affects the nonequilibrium features of PSS/CTAB association via
enhancing the kinetically stable concentration range of overcharged
polyion/surfactant nanoparticle dispersions. With increasing C<sub>12</sub>G<sub>2</sub> concentration, however, an opposite effect
of the uncharged additive dominates. Namely, the CTAB molecules are
solubilized excessively into mixed surfactant micelles, which reduces
the surface charge of the PSS/CTAB/C<sub>12</sub>G<sub>2</sub> nanoparticles
and thus destabilizes their dispersion. At appropriately large nonionic
surfactant concentrations, the binding of CTAB is largely reduced,
resulting in the redissolution of the precipitate. In contrast, neither
the destabilization nor the resolubilization effects of the added
dodecyl maltoside were observed for the PSS/DTAB system due to the
much lower driving force of DTAB binding compared to CTAB. Our results
clearly demonstrate that the alkyl chain length of the ionic amphiphile
has a pronounced effect on both the equilibrium and nonequilibrium
aspects of polyion/mixed surfactant complexation which might be further
exploited in various next generation applications.