Probing the Formation of Wormlike Micelles Formed by Cationic Surfactant with Chlorobenzoate Derivatives

Abstract

The energy released when tetradecyltrimethylammonium bromide (C 14 TAB) is combined with different derivatives of chlorobenzoates in an isothermal titration calorimeter (ITC) allows a direct evaluation of the spontaneity of the threading of the aromatic anions into the micellar palisade. The comparison between the enthalpimetric curves with the ones for viscosity of the solutions, hydrodynamic radii of the aggregates (dynamic light scattering experiments), and the fraction of aromatic anions incorporated (diffusion-ordered spectroscopy experiments) allows the establishment of the variations of enthalpy with formation, growth, and decrease of the wormlike micelles (WLMs). The formation of WLMs with C 14 TAB is very favored (very exothermic) for titrations of chlorobenzoate derivatives which present the chlorine atom in positions 3 or 4 of the aromatic ring. However, the aggregation is highly unfavorable if chlorine is at position 2 of chlorobenzoate. According to the results, the high potential of the ITC to determine critical concentrations and the energies associated with the aggregation of a cationic surfactant and aromatic anions for the formation of WLMs was demonstrated.

Light-Triggered Rheological Changes in a System of Cationic Wormlike Micelles Formulated with a Photoacid Generator

“…Figure B shows that BA serves to increase η 0 over the pH range of 4–7. In this pH range, DHB is protonated, but BA becomes deprotonated and has low affinity for the micellar palisade. , Thus, BA induces WLMs of CTAB in this pH range. Surprisingly, the η 0 value for the solution containing all the four components (CTAB, DHB, BA, and IB) is much higher than that with three out of the four components.…”

“…Surfactants are amphiphilic molecules that can self-assemble in solution into different types of aggregates such as spherical micelles, WLMs, − hexagonal phases, lamellae, vesicles, and others. − The structure of the aggregate can be rationalized by considering the geometry of the surfactant molecule in terms of the critical packing parameter (CPP) . This CPP depends on the molecular identity of the surfactant, the presence of salt or some specific cosolutes, temperature, concentration, ionic strength, and so on.…”

Performance Evaluation and Mechanism Study of Seawater-Based Circulatory Fracturing Fluid Based on pH-Regulated WormLike Micelles

“…The measured hydrodynamic radius ( R h ) of the dynamic light scattering can reflect changes in the aggregate structure in solution ( Jora et al, 2019 ). As shown in Figure 9 , when the pH value of the mixed solution is equal to 8.12, the value of R h is 28.2 nm, which shows that some longer wormlike micelles are formed in the system.…”

Unusual Increasing Viscoelasticity of Wormlike Micelles Composed of Imidazolium Gemini Surfactants with Temperature

“…What is more interesting is that the viscoelasticity of the formed wormlike micelles increases over a range of increasing temperatures and then decreases above a critical temperature. These wormlike micelles exhibit the thermal thickening property and retain high viscoelasticity up to 95.1 °C, which is larger than that of most cationic wormlike micelles. , Wormlike micelles formed at high temperatures have the potential to be used as supramolecular templates for the synthesis of functional materials and in relatively high-temperature (>90 °C) oilfields. With the increase of the chain length of [C n -2-C n im]­Br 2 , the transition temperature of lamellar liquid crystals to wormlike micelles and the disintegration temperature of wormlike micelles increase.…”