Micellization of Sodium Decyl Naphthalene Sulfonate Studied by¹H NMR

Abstract

H chemical shift changes of a newly synthesized anionic surfactant, sodium decyl naphthalene sulfonate (SDNS), show that its critical micellar concentration (cmc) lies between 0.82 and 0.92 mM, which is in agreement with that measured by the surface tension method (0.8 mM). The difference in aromatic ring current effect on the naphthyl protons, the different changes in their spin-spin relaxation times upon micellization, and the appearance of cross-peaks between intermolecular protons in the aqueous micellar solution give information about the relative arrangement of the naphthyl rings in the SDNS micelles.

Micellization Behavior of Surface Active Ionic Liquids Having Aromatic Counterions in Aqueous Media

“…There are other factors such as the presence of water in upper palisade layer near imidazolium headgroup, effect of ring current by the imidazolium ring, or the effect of ring current by aromatic anions on the intermolecular protons of aromatic ring. 46 As indicated from fluorescence measurements and 1 H NMR measurements, it is inferred that both the penetration of water along with ring currents seems to dominate the change in chemical shift in case of [C 16 mim][HBS], where [HBS] − is present in between the imidazolium groups. The effect of imidazolium ring currents however is assumed to negligible in case of [C 16 mim][BS] and [C 16 mim][PTS].…”

Synthesis, aggregation behavior and interfacial activity of branched alkylbenzenesulfonate gemini surfactants

“…Variation of chemical shifts versus surfactant concentrations can provide useful information on critical aggregate concentration, aggregation number (N), and intermolecular interaction [36][37][38][39][40][41][42][43][44]. Moreover, the ring current of aromatic group affects the chemical shifts of nearby protons and provides evidence on its locus in micelles [45]. The assignments of the hydrogen atoms on the carbons of the studied surfactants have been shown in Fig.…”

Mixed micelles of sodium 4-decyl naphthalene sulfonate with Triton X-100 and sodium dodecyl sulfonate analyzed by 1H NMR

“…In order to examine the properties of SDNS aqueous solution in the presence of nonionic surfactant TX-100, 1 H NMR parameters were measured at 298 K with different molar ratios of TX-100 at a constant concentration of SDNS (three times its CMC), respectively, and were compared with those of the individual surfactant solutions at the same corresponding concentrations [19,23].…”

“…Recently we have studied the behavior of sodium 4-decyl naphthalene sulfonate (SDNS) in aqueous solution by these methods at 298 and 313 K in detail. Their dynamic properties show some difference from those of the linear alkyl sulfonates [23,24]. It would be interesting to gain insight into the relative arrangement of the different kinds of surfactant molecules in the mixed micelles of SDNS with the presence of TX-100 and SDSN, respectively.…”

“…The CMCs of SDSN at 313 K and TX-100 at 298 K are 9.7 [25] and 0.30 mmol/dm 3 [26], respectively. The CMCs of SDNS at 298 and 313 K are in the same range, between 0.82 and 0.92 mmol/dm 3 [23,24]. NMR measurements are performed on a UNITY INOVA-500 spectrometer with a 1 H frequency of 500.13 MHz.…”