Article
Chemistry, Physical
Sadafara A. Pillai, Vinod Kumar, Ketan Kuperkar, Debes Ray, Vinod K. Aswal, Sanjeev Kumar
Summary: The study reveals strong interactions between T1304 and cationic surfactants, which induce micellization and lower the critical micellization temperature of T1304. However, cationic surfactants also enhance the surface charge on copolymeric micelles, leading to the formation of mixed micelles.
COLLOID AND INTERFACE SCIENCE COMMUNICATIONS
(2021)
Article
Physics, Multidisciplinary
Yu. A. Eroshkin, L. Ts. Adzhemyan, A. K. Shchekin
Summary: A new statistical thermodynamic model is proposed to describe the inverse nonionic aggregates of surfactant molecules in nonpolar solvents. This model considers the coexistence of inverse spherical, globular, and spherocylindrical aggregates without activation barriers between them. It introduces the concept of uniform bulk density and two independent geometric parameters to characterize the transformation of aggregates into different forms. The model shows good agreement with experimental data and predicts the degrees of surfactant micellization in various forms of inverse aggregates.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2023)
Article
Chemistry, Physical
Yingying Zuo, Junfeng Lv, Ning Wei, Xiguang Chen, Jing Tong
Summary: Ionic liquid surfactants have shown potential as substitutes for traditional amphiphiles due to their tunability and superior properties. However, the effect of cationic structure and anion type on their surface properties remains unclear.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Chemistry, Physical
Mona S. Minkara, Tyler R. Josephson, Connor L. Venteicher, Benjamin R. Greenvall, Rebecca K. Lindsey, Peter H. Koenig, J. Ilja Siepmann
Summary: In this study, the adsorption behavior of n-nonane/1-hexanol mixtures in a lamellar phase was investigated using Monte Carlo simulations. It was found that C9 and C6OH molecules have different spatial preferences, and the enhanced adsorption in the binary mixture is mainly attributed to C9-C9 interactions.
JOURNAL OF PHYSICAL CHEMISTRY B
(2022)
Article
Chemistry, Multidisciplinary
Laishun Shi, Jingqiu Ma, Yawen Chen
Summary: A series of amphoteric surfactants containing carboxyl group and sodium sulfonate were synthesized and their surface activity and thermodynamic parameters were studied. The results showed that the critical micelle concentration and adsorption area decreased with the increase of hydrophobic carbon chain length, while the balance surface tension first decreased and then increased. These amphoteric surfactants have low foaming properties.
RESEARCH ON CHEMICAL INTERMEDIATES
(2022)
Article
Chemistry, Physical
Mukul Kumar, Shalya Raj, Uttam Thapa, Sandeepika Singh, Anirudh Srivastava
Summary: The study found that NaCMCu as a polycounterion can enhance the stability of CTZ + SDS mixed micelles, decrease the CMC of CTZ, and bind CTZ micelles through electrostatic interactions. However, an increase in NaCMCu was observed to result in an increase in the size of mixed micelles.
JOURNAL OF MOLECULAR LIQUIDS
(2021)
Article
Chemistry, Applied
Lukas Fliri, Gabriel Partl, Daniel Winkler, Gerhard Laus, Thomas Muller, Herwig Schottenberger, Michael Hummel
Summary: This study investigates the influence on solution behavior and solvatochromism caused by attaching a 1H,1H,2H,2H-perfluomoctyl side chain to derivatives of the Brooker's Merocyanine chromophore. The observed changes in spectral characteristics and convergence of maxima at specific wavelengths in different solvents suggest that aggregation might contribute to the phenomena observed. Further concentration-dependent UV-Vis measurements were conducted to support the proposed hypothesis.
Article
Chemistry, Physical
Rajesh Banik, Sourav Das, Asitanga Ghosh, Soumen Ghosh
Summary: This study investigated the formation of aggregates using different compositions of alkyl betaine gemini surfactant (C14Ab) with chlorpromazine hydrochloride (CPZ). The results showed that the CPZ/C14Ab system has different characteristics in forming aggregates compared to single-chain zwitterionic surfactant (C12DmCB) of the same type with CPZ. The study also revealed differences in the hydrophilic environment between the CPZ/C14Ab system and the CPZ/C12DmCB system.
Article
Chemistry, Physical
Rajesh Banik, Sourav Das, Asitanga Ghosh, Soumen Ghosh
Summary: This study investigated the formation of aggregates by different compositions of alkyl betaine gemini surfactant (C14Ab) with chlorpromazine hydrochloride (CPZ). Various experimental methods were used to observe the characteristics of the aggregates in the CPZ/C14Ab system and compared with a single-chain zwitterionic surfactant (C12DmCB) of the same type with CPZ. The relative polarity near the head group regions of the mixed micelle systems was revealed by fluorescence decay measurements. The study also employed theoretical models to analyze the different interaction parameters. This systematic study provides unique insights into the interaction between zwitterionic gemini amphiphiles and other amphiphiles with an amphiphilic drug molecule.
Article
Chemistry, Multidisciplinary
Mohd Sajid Lone, Saima Afzal, Oyais Ahmad Chat, Vinod Kumar Aswal, Aijaz Ahmad Dar
Summary: The mixture of cetyltrimethylammonium bromide (CTAB) and 1-butyl-3-methylimidazoliumdodecyl sulfate (bmimDS) has been found to undergo phase transitions from vesicles to micelles as a function of temperature, with some mole fractions of CTAB showing dual transitions. Solutions with certain mole fractions exhibit a single transition from vesicles to cylindrical micelles, while others show dual structural transitions at different temperatures. This unique microstructural transition in a combination of cationic and anionic surfactants without additives has not been reported previously.
Article
Chemistry, Multidisciplinary
Manpreet Singh, Sugam Kumar, Vinod Kumar Aswal, Tejwant Singh Kang
Summary: The aggregation behavior of the SAIL and GS in aqueous medium has been studied using various techniques. The extent of synergistic interactions between the components depends on the composition of the surfactant mixture. The properties of the aggregates are influenced by hydrophobic and dipolar interactions, as well as counterion binding.
Article
Multidisciplinary Sciences
Yige Zhang, Xiaowen Xie, Jianliang Liu, Boyuan Tang, Can Fang, Xiaoming Liu, Zhifeng Dai, Yubing Xiong
Summary: This study designed and synthesized azobenzimidazole ionic liquids with reversible photo-induced conductivity regulation. The change of electrical conductivity under UV/visible light irradiation was investigated, and the effect of chemical structure and concentration of the ionic liquids on the photoresponse conductivity regulation was discussed. The results showed that UV light significantly increased the conductivity of the ionic liquid, with longer alkyl chains leading to even greater increases. Visible light irradiation returned the electrical conductivity to its initial value. The reversible photo-induced conductivity regulation was attributed to the formation/dissociation of ionic liquid aggregates induced by the isomerization of azobenzene under light irradiation.
SCIENTIFIC REPORTS
(2023)
Article
Chemistry, Physical
Iva Manasi, Mohammad R. Andalibi, Ria S. Atri, Jake Hooton, Stephen M. King, Karen J. Edler
Summary: Understanding and manipulating micelle morphology in Deep Eutectic Solvents (DESs) is crucial for utilizing surfactants effectively. Recent studies have shown that the self-assembly of surfactants in DESs influences the size, shape, and morphology of micelles formed. Different types of surfactants form distinct micelle shapes in DESs, with the mechanism behind these differences being related to the interactions between the surfactant molecules and the solvent components.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Ennio Lavagnini, Joanne L. Cook, Patrick B. Warren, Christopher A. Hunter
Summary: New methods have been described to calculate DPD parameters directly from chemical structure, allowing for a wider range of organic compounds to be simulated.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Chemistry, Multidisciplinary
Barnali Banerjee, Santanu Paria
Summary: The study investigates the solution behaviors of the binary mixture of double chain cationic surfactant DDAB with nonionic surfactants EO-9 and EO-40 under different conditions, showing nonideal behavior. Coexistence of nonionic surfactants leads to a decrease in CMC, CVC, and surface tension of DDAB at two concentrations.
Article
Physics, Multidisciplinary
L. Ts Adzhemyan, Yu A. Eroshkin, A. K. Shchekin
Summary: This study analyzed the relaxation process in micellar solutions of nonionic one-component surfactants based on numerical solutions of linearized Becker-Doring equations. By determining characteristic eigenvectors and eigenvalues, relaxation modes for ultrafast, fast, and slow relaxation stages were localized in the space of aggregation numbers. Analytical methods and numerical computations were used to find relaxation times and modes for these different stages, providing a comprehensive understanding of relaxation in micellar solutions.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2021)
Article
Chemistry, Physical
A. K. Shchekin, L. A. Gosteva, T. S. Lebedeva, D. Tat'yanenko
Summary: The classical density functional theory allows explicit calculation of various properties of thin interlayers between solid surfaces and different phases, while a unified approach can determine the uniform thickness of liquid films or thin layers formed at different chemical potentials. Mechanical and thermodynamic definitions of disjoining pressure have been proven consistent through calculations, revealing that the disjoining pressure decreases in vapor layers around nanosized hydrophobic particles as particle radius increases.
Article
Chemistry, Physical
Alexander K. Shchekin, Liubov A. Gosteva, Dmitry V. Tatyanenko
Summary: Classical square-gradient density functional theory was used to describe the disjoining pressure in vapor layers, revealing that the pressure tensor is significantly anisotropic in the vapor layers near the smooth solid surfaces. Comparison of mechanical and thermodynamic definitions of the disjoining pressure in the spherical vapor layer showed consistency.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2021)
Article
Chemistry, Physical
Anatoly E. Kuchma, Alexander K. Shchekin
Summary: The non-stationary diffusion growth and kinetics of overcritical gas bubbles in a supersaturated liquid solution have been analytically described, taking into account the influence of viscous and capillary forces. The results are general and not limited by gas supersaturation and solubility values.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Correction
Chemistry, Physical
A. K. Shchekin, L. A. Gosteva, T. S. Lebedeva, D. V. Tat'yanenko
Article
Chemistry, Physical
A. K. Shchekin, N. A. Volkov, I. N. Koltsov, N. Yu. Tretyakov, S. S. Volkova, E. A. Turnaeva
Summary: A thermodynamic model has been developed to describe the formation of molecular aggregates in a solution with nonionic surfactants and solubilisate molecules. The model predicts the aggregation work, relative concentrations distribution, and the possibility of significant accumulation of solubilisate molecules in the aggregates. It also shows that stable nanoemulsions have narrow ranges of limiting concentrations for the nonionic surfactant and solubilisate.
Article
Chemistry, Physical
N. A. Volkov, Yu. A. Eroshkin, A. K. Shchekin, I. N. Koltsov, N. Yu. Tretyakov, E. A. Turnaeva, S. S. Volkova, A. A. Groman
Summary: All-atom molecular dynamics was employed to study self-aggregation and solubilization processes in aqueous solutions containing decane, ionic and nonionic surfactants, and additives of salts. Micellization of anionic surfactant in the presence of hydrocarbon was simulated under preset conditions, and self-aggregation was also simulated in systems with different combinations of surfactants and hydrocarbons. Diffusion coefficients and viscosities of the solutions were calculated for aggregates containing hydrocarbon and surfactants.
Article
Chemistry, Physical
A. K. Shchekin, L. Ts Adzhemyan, Yu A. Eroshkin, N. A. Volkov
Summary: The derivation of an expression for the minimal work of micellization based on the extended droplet model has been considered for direct and inverse spherical micelles. Several factors contributing to the aggregation work have been taken into account, providing an explanation for the mechanism of surfactant aggregation in a nonpolar solvent.
Article
Chemistry, Multidisciplinary
A. K. Shchekin, D. Tatyanenko, L. A. Gosteva, K. D. Apitsin
Summary: This study compares the dependencies of pressure, chemical potential, and free-energy density on the number density of particles in a homogeneous system of hard spheres using different equations of state. The results show that the agreement between the 6th-order Rusanov equations and the virial expansion is better in the high-density region, while the Carnahan-Starling equation shows slightly better agreement with the virial expansion in the low- and medium-density regions. The choice of equation of state affects the values of quantities characterizing two-phase equilibrium and can shift the size of droplets or bubbles. The molecular density profiles and surface tension of small droplets and bubbles of an argon-like substance are also calculated and analyzed.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
A. E. Kuchma, A. K. Shchekin
Summary: The traditional approach of mean-field supersaturation for kinetic description of nucleation is based on assumptions that may not hold under certain conditions. The excluded volume approach provides a better description of the kinetic process of phase transition.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY
(2022)
Article
Physics, Multidisciplinary
A. K. Shchekin, A. E. Kuchma, E. V. Aksenova
Summary: This study presents an analytical and numerical investigation of the diffusion growth of overcritical gas bubbles during the degassing of supersaturated gas solutions. The study considers the explicit effects of viscous and capillary forces on internal pressure in the bubbles, based on a recent semi-analytical approach. The research findings show that the growth rate of overcritical bubbles is influenced by gas supersaturation, gas diffusivity and solubility in solution, solution viscosity, and surface tension at the bubble surface. The study also explores the stationary diffusion regime and the self-similar non-stationary diffusion regime. Analytical formulas and asymptotic formulas are derived to describe the growth rate and correction function for different conditions.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2023)
Article
Physics, Multidisciplinary
Yu. A. Eroshkin, L. Ts. Adzhemyan, A. K. Shchekin
Summary: A new statistical thermodynamic model is proposed to describe the inverse nonionic aggregates of surfactant molecules in nonpolar solvents. This model considers the coexistence of inverse spherical, globular, and spherocylindrical aggregates without activation barriers between them. It introduces the concept of uniform bulk density and two independent geometric parameters to characterize the transformation of aggregates into different forms. The model shows good agreement with experimental data and predicts the degrees of surfactant micellization in various forms of inverse aggregates.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2023)
Review
Chemistry, Multidisciplinary
A. K. Shchekin
Summary: Theoretical results on the thermodynamic and structural characteristics of free droplets and bubbles around nanosized solid heterogeneous spherical inclusions are reviewed in this study. The phenomenological thermodynamic approach and various versions of the molecular density functional method are used. The structure of droplets and bubbles is described by equilibrium molecular density profiles, and thermodynamic characteristics include the chemical potential of molecules, the work of formation, and the surface tension and disjoining pressure.
RUSSIAN CHEMICAL BULLETIN
(2023)
Article
Chemistry, Physical
Alexander K. Shchekin, Anatoly E. Kuchma, Elena V. Aksenova
Summary: A detailed statistical description of the evolution of supersaturated-by-gas solution at degassing has been presented based on the time-dependent distribution in radii of overcritical gas bubbles. This study considers the influence of solution viscosity and capillarity on the bubble diameter distribution, until the gas supersaturation drops and stops nucleation of new bubbles. Numerical simulations were conducted to analyze the effects of various factors on the distribution function of overcritical bubbles, including solution viscosities and initial rate of homogeneous bubble nucleation.
COLLOIDS AND INTERFACES
(2023)
Article
Chemistry, Physical
L. A. Gosteva, A. K. Shchekin
Summary: This study compared stable equilibrium density profiles surrounding nonwettable nanoparticles immersed in a liquid phase using three different methods, showing that the gradient approximation somewhat overestimates the thickness of the vapor interlayer, but is qualitatively consistent with other approaches.