Coacervation is a phenomenon in which a colloidal dispersion separates into two immiscible liquid phases: a liquid rich in colloidal phase in equilibrium with another diluted liquid phase. Surfactant coacervation here refers to coacervation whose main components are surfactants with low molecular weights. Over the past two decades, surfactants have been greatly developed and studies on coacerva...

Using dissipative particle dynamics (DPD) simulations, we explore the specifics of micellization in the solutions of anionic and cationic surfactants and their mixtures. Anionic surfactant sodium dodecyl sulfate (SDS) and cationic surfactant cetyltrimethylammonium bromide (CTAB) are chosen as characteristic examples. Coarse-grained models of the surfactants are constructed and parameterized usi...

Recent research has reported many attractive benefits from short peptide amphiphiles. A practical route for them to enter the real world of applications is through formulation with conventional surfactants. This study reports the co-adsorption of the surfactant-like peptide, V6K, with conventional anionic and cationic surfactants at the solid/water interface. The time-dependant adsorption behav...

Three new types of Gemini amphiphiles (N ,N ?-bis-(4-decyloxybenzylidene)-ethane-1,2-diamine, N ,N ?-bis-(4decyloxy-2-hydroxybenzylidene)-ethane-1,2-diamine, and (N ,N ?-bis-(4-decyloxy-2-hydroxybenzylidene)-ethane-1,2diamine)copper(II) were synthesized. Their aggregation behaviors were studied by TEM observation and monolayer experiments. It was found that the vesicle formation and transformat...

Complexes obtained from the electrostatic interactions between chitosan, a cationic polysaccharide, and sodium decylsulfonate, an anionic surfactant, were characterized by their conductimetric and surface-active properties. Such surfactant/polyelectrolyte complexes (SPECs) present very interesting surface-active properties, even at very low surfactant concentrations (much lower than the critica...

In this report, results from the project, proposed in the original research plan are presented. 10 surfactant systems effective as drag reducing agents (DRA’s) in efficient district cooling, including four commercial cationic surfactants, one commercial and three novel synthesized zwitterionic surfactants, one commercial nonionic surfactant and one zwitterionic(synthesized)/anionic surfactant m...

The adsorption/desorption behavior of the cationic surfactant tetradecyl trimethyl ammonium chloride (TTAC) at the alumina-water interface and the change in the structure of surfactant aggregates at the interface were studied using the fluorescence spectroscopic technique along with electrophoresis. As expected, the cationic TTAC adsorbed significantly on the negatively charged alumina particle...

Monomeric thiol surfactants, [C(n)H(2n+1)N(CH(3))(2)CH(2)CH(2)SH]Br, were produced by the cleavage of gemini surfactant containing a disulfide bond in the spacer chain, [C(n)H(2n+1)N(CH(3))(2)CH(2)CH(2)SSCH(2)CH(2)N(CH(3))(2)C(n)H(2n+1)]2Br. The disulfide bond was completely reduced by the addition of four times moles of dithiothreitol in water at room temperature. The critical micelle concentr...

Self-assembly in mixtures of cationic and anionic surfactants occurs synergistically because of attractive interactions between the oppositely charged headgroups. Here, such effects are exploited to obtain highly viscoelastic fluids at low total surfactant concentration. The systems considered are mixtures of the C18tailed anionic surfactant, sodium oleate (NaOA), and cationic surfactants from ...