1
|
Zhang B, Pinky SK, Kwansa AL, Ferguson S, Yingling YG, Stiff-Roberts AD. Correlation of Emulsion Chemistry, Film Morphology, and Device Performance in Polyfluorene LEDs Deposited by RIR-MAPLE. ACS APPLIED MATERIALS & INTERFACES 2023; 15:18153-18165. [PMID: 36988336 DOI: 10.1021/acsami.3c03012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Thin films of polyfluorene (PFO) were deposited using emulsion-based resonant infrared, matrix-assisted pulsed laser evaporation (RIR-MAPLE). Here, it is shown that properly selected surfactant chemistry in the emulsion can increase crystalline β phase (β-PFO) content and consequently improve the color purity of light emission. To determine the impact of surfactant on the device performance of resulting films, blue light-emitting diodes (LEDs) with PFO as an active region were fabricated and compared. Molecular dynamics (MD) simulations were used to explain the physical and chemical changes in the emulsion properties as a function of the surfactant. The results indicate that the experimental film morphology and device performance are highly correlated to the emulsion droplet micelle structure and interaction energy among PFO, primary solvent, and water obtained from MD simulations. While the champion device performance was lower than other reported devices (luminous flux ∼0.0206 lm, brightness ∼725.58 cd/m2, luminous efficacy ∼0.0548 lm/W, and luminous efficiency ∼0.174 cd/A), deep blue emission with good color purity (CIE chromaticity diagram coordinate of (0.177,0.141)) was achieved for low operating voltages around 3 V. Furthermore, a much higher β-phase content of 21% was achieved in annealed films (without the pinholes typically found in β-PFO deposited by other techniques) by using sodium dodecyl sulfate (SDS) as the surfactant.
Collapse
Affiliation(s)
- Buang Zhang
- Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Sabila K Pinky
- Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27606, United States
| | - Albert L Kwansa
- Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27606, United States
| | - Spencer Ferguson
- Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Yaroslava G Yingling
- Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27606, United States
| | - Adrienne D Stiff-Roberts
- Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708, United States
- University Program in Materials Science and Engineering, Duke University, Durham, North Carolina 27708, United States
| |
Collapse
|
2
|
Kumar D, Suna A, Ray D, Aswal VK, Bahadur P, Tiwari S. Structural Changes in Liposomal Vesicles in Association with Sodium Taurodeoxycholate. AAPS PharmSciTech 2023; 24:95. [PMID: 37012522 DOI: 10.1208/s12249-023-02550-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 03/06/2023] [Indexed: 04/05/2023] Open
Abstract
Liposomes composed of soy lecithin (SL) have been studied widely for drug delivery applications. The stability and elasticity of liposomal vesicles are improved by incorporating additives, including edge activators. In this study, we report the effect of sodium taurodeoxycholate (STDC, a bile salt) upon the microstructural characteristics of SL vesicles. Liposomes, prepared by the thin film hydration method, were characterized by dynamic light scattering (DLS), small-angle neutron scattering (SANS), electron microscopy, and rheological techniques. We noticed a reduction in the size of vesicles with the incremental addition of STDC. Initial changes in the size of spherical vesicles were ascribed to the edge-activating action of STDC (0.05 to 0.17 µM). At higher concentrations (0.23 to 0.27 µM), these vesicles transformed into cylindrical structures. Morphological transitions at higher STDC concentrations would have occurred due to its hydrophobic interaction with SL molecules in the bilayer. This was ascertained from nuclear magnetic resonance observations. Whereas shape transitions underscored the deformability of vesicles in the presence of STDC, the consistency of bilayer thickness ruled out any dissociative effect. It was interesting to notice that SL-STDC mixed structures could survive high thermal stress, electrolyte addition, and dilution.
Collapse
Affiliation(s)
- Deepak Kumar
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), Raebareli, Lucknow, 226002, India
| | - Abhishek Suna
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), Raebareli, Lucknow, 226002, India
| | - Debes Ray
- Solid State Physical Division, Bhabha Atomic Research Centre, Mumbai, 400085, India
| | - Vinod K Aswal
- Solid State Physical Division, Bhabha Atomic Research Centre, Mumbai, 400085, India
| | - Pratap Bahadur
- Department of Chemistry, Veer Narmad South Gujarat University, Surat, Gujarat, 395007, India
| | - Sanjay Tiwari
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), Raebareli, Lucknow, 226002, India.
| |
Collapse
|
3
|
Drag Reduction Using Additives in Smooth Circular Pipes Based on Experimental Approach. Processes (Basel) 2021. [DOI: 10.3390/pr9091596] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Reduction of fluid resistance using the rheological characteristics of a polymer-surfactant solvent is research that contains many aspects, such as the theory of the drag reduction process, historical journey, and ongoing current research development. Many studies have been conducted, but it is challenging to know all existing and new research threads. The present investigation was conducted using literature studies regarding drag reducing agents. This research will also discuss the characteristics of flowing fluids and their effects on the velocity profile with friction factor of flowing fluids in smooth circular straight pipe geometries based on experimental, theoretical approaches. It concludes with aspects of research conducted around reducing drag using drag reducing agents, ideas about innovations, structuring overlook in testing, and modification of the fluid flow state.
Collapse
|
4
|
Butler CSG, King JP, Giles LW, Marlow JB, Vidallon MLP, Sokolova A, de Campo L, Tuck KL, Tabor RF. Design and synthesis of an azobenzene-betaine surfactant for photo-rheological fluids. J Colloid Interface Sci 2021; 594:669-680. [PMID: 33780770 DOI: 10.1016/j.jcis.2021.02.061] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 01/22/2021] [Accepted: 02/13/2021] [Indexed: 12/29/2022]
Abstract
HYPOTHESIS Morphology of surfactant self-assemblies are governed by the intermolecular interactions and packing constraints of the constituent molecules. Therefore, rational design of surfactant structure should allow targeting of the specific self-assembly modes, such as wormlike micelles (WLMs). By inclusion of an appropriate photo-responsive functionality to a surfactant molecule, light-based control of formulation properties without the need for additives can be achieved. EXPERIMENTS A novel azobenzene-containing surfactant was synthesised with the intention of producing photo-responsive wormlike micelles. Aggregation of the molecule in its cis and trans isomers, and its concomitant flow properties, were characterised using UV-vis spectroscopy, small-angle neutron scattering, and rheological measurements. Finally, the fluids capacity for mediating particle diffusion was assessed using dynamic light scattering. FINDINGS The trans isomer of the novel azo-surfactant was found to form a viscoelastic WLM network, which transitioned to inviscid ellipsoidal aggregates upon photo-switching to the cis isomer. This was accompanied by changes in zero-shear viscosity up to 16,000×. UV-vis spectroscopic and rheo-SANS analysis revealed π-π interactions of the trans azobenzene chromophore within the micelles, influencing aggregate structure and contributing to micellar rigidity. Particles dispersed in a 1 wt% surfactant solution showed a fivefold increase in apparent diffusion coefficient after UV-irradiation of the mixture.
Collapse
Affiliation(s)
- Calum S G Butler
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia
| | - Joshua P King
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia
| | - Luke W Giles
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia
| | - Joshua B Marlow
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia
| | | | - Anna Sokolova
- Australian Centre for Neutron Scattering, ANSTO, Lucas Heights, New South Wales 2234, Australia
| | - Liliana de Campo
- Australian Centre for Neutron Scattering, ANSTO, Lucas Heights, New South Wales 2234, Australia
| | - Kellie L Tuck
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia.
| | - Rico F Tabor
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia.
| |
Collapse
|
5
|
Rafique AS, Khodaparast S, Poulos AS, Sharratt WN, Robles ESJ, Cabral JT. Micellar structure and transformations in sodium alkylbenzenesulfonate (NaLAS) aqueous solutions: effects of concentration, temperature, and salt. SOFT MATTER 2020; 16:7835-7844. [PMID: 32756697 DOI: 10.1039/d0sm00982b] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We investigate the shape, dimensions, and transformation pathways of micelles of linear sodium alkylbenzenesulfonate (NaLAS), a common anionic surfactant, in aqueous solution. Employing Small Angle Neutron Scattering (SANS) and surface tensiometry, we quantify the effects of surfactant concentration (0.6-15 wt%), temperature (5-40 °C) and added salt (≤0.35 M Na2SO4). Spherical micelles form at low NaLAS (≤2.6 wt%) concentration in water, and become elongated with increasing concentration and decreasing temperature. Addition of salt reduces the critical micelle concentration (CMC) and thus promotes the formation of micelles. At fixed NaLAS concentration, salt addition causes spherical micelles to grow into cylindrical micelles, and then multilamellar vesicles (MLVs), which we examine by SANS and cryo-TEM. Above a threshold salt concentration, the MLVs reach diameters of 100 s of nm to few μm, eventually causing precipitation. While the salt concentrations associated with the micelle-to-cylinder transformation increase only slightly with temperature, those required for the cylinder-to-MLV transformation exhibit a pronounced, linear temperature dependence, which we examine in detail. Our study establishes a solution structure map for this model anionic surfactant in water, quantifying the combined roles of concentration, temperature and salt, at practically relevant conditions.
Collapse
Affiliation(s)
- Aysha S Rafique
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
| | - Sepideh Khodaparast
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
| | - Andreas S Poulos
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
| | - William N Sharratt
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
| | - Eric S J Robles
- The Procter & Gamble Company, Newcastle Innovation Centre, Newcastle-Upon-Tyne, NE12 9TS, UK
| | - João T Cabral
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
| |
Collapse
|
6
|
Bhattarai A. Studies of aggregation properties of surfactant with and without polyelectrolyte in water and binary mixture of methanol-water from the surface tension measurements. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.113438] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
7
|
Campos-Villalobos G, Siperstein FR, Charles A, Patti A. Solvent-induced morphological transitions in methacrylate-based block-copolymer aggregates. J Colloid Interface Sci 2020; 572:133-140. [PMID: 32240786 DOI: 10.1016/j.jcis.2020.03.067] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 02/25/2020] [Accepted: 03/18/2020] [Indexed: 01/28/2023]
Abstract
Poly(ethylene oxide)-b-poly(butylmethacrylate) (PEO-b-PBMA) copolymers have recently been identified as excellent building blocks for the synthesis of hierarchical nanoporous materials. Nevertheless, while experiments have unveiled their potential to form bicontinuous phases and vesicles, a general picture of their phase and aggregation behavior is still missing. By performing Molecular Dynamics simulations, we here apply our recent coarse-grained model of PEO-b-PBMA to investigate its self-assembly in water and tetrahydrofuran (THF) and unveil the occurrence of a wide spectrum of mesophases. In particular, we find that the morphological phase diagram of this ternary system incorporates bicontinuous and lamellar phases at high copolymer concentrations, and finite-size aggregates, such as dispersed sheets or disk-like aggregates, spherical vesicles and rod-like vesicles, at low copolymer concentrations. The morphology of these mesophases can be controlled by tuning the THF/water relative content, which has a striking effect on the kinetics of self-assembly as well as on the resulting equilibrium structures. Our results disclose the fascinating potential of PEO-b-PBMA copolymers for the templated synthesis of nanostructured materials and offer a guideline to fine-tune their properties by accurately selecting the THF/water ratio.
Collapse
Affiliation(s)
- Gerardo Campos-Villalobos
- Department of Chemical Engineering and Analytical Science, University of Manchester, Sackville Street, Manchester M13 9PL, UK
| | - Flor R Siperstein
- Department of Chemical Engineering and Analytical Science, University of Manchester, Sackville Street, Manchester M13 9PL, UK
| | - Arvin Charles
- Department of Chemical Engineering and Analytical Science, University of Manchester, Sackville Street, Manchester M13 9PL, UK
| | - Alessandro Patti
- Department of Chemical Engineering and Analytical Science, University of Manchester, Sackville Street, Manchester M13 9PL, UK.
| |
Collapse
|
8
|
Interfacial and Micellization Behavior of Cetyltrimethylammonium Bromide (CTAB) in Water and Methanol-Water Mixture at 298.15 to 323.15 K. J CHEM-NY 2020. [DOI: 10.1155/2020/4653092] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The micellization behavior of cetyltrimethylammonium bromide (CTAB) in water , 0.1, 0.2, 0.3, and 0.4 volume fractions of methanol at 298.15, 308.15, 318.15, and 323.15 K were investigated by surface tension measurements. The effect of methanol on values of critical micelle concentration (cmc), free energies of micellization ΔGmo, and surface properties viz. maximum surface excess concentration Γmax, area occupied by per surfactant molecule Amin, surface pressure πcmc, solution surface tension γcmc, solvent surface tension (γo), free energies of adsorption ΔGadso, the efficiency of adsorption (pC20), effective Gibbs free energy ΔGeffo, and free energy of surface at equilibrium (Gmin) were investigated using surface tension values. Other parameters such as the packing parameter (P), aggregation number (N), concentration of surfactant in the bulk phase (C20), relation between Amin and πcmc, and correlation of slopes dγ/d log C, γo/γcmc, Γ/Γmax, cmc/C20, ΔGadso/ΔGmo, and cmc/pC20 with the volume fraction of methanol are calculated and discussed in the light of the experiment done.
Collapse
|
9
|
Choi F, Chen R, Acosta EJ. Predicting the effect of additives on wormlike micelle and liquid crystal formation and rheology with phase inversion phenomena. J Colloid Interface Sci 2019; 564:216-229. [PMID: 31911226 DOI: 10.1016/j.jcis.2019.12.105] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 11/10/2019] [Accepted: 12/24/2019] [Indexed: 11/27/2022]
Abstract
HYPOTHESIS Surfactant-based viscoelastic fluids are used in consumer products such as body wash, cosmetics, and in hydraulic fracturing fluids to suspend proppant, among others. The solubilization of oil within these fluids changes the curvature of the surfactant and their nanostructure and rheological properties. The curvature-based hydrophilic-lipophilic-difference + net-average-curvature (HLD-NAC) framework may be able to quantify curvature changes and predict the formulation conditions required to obtain viscoelasticity. EXPERIMENTS Phase inversion experiments were conducted for combinations of commercial-grade C8, C10 and C12 tetrapropylene glycol ether sulfate (extended) surfactant and sodium dihexyl sulfosuccinate with oil to obtain the HLD-NAC parameters. Wormlike micelles (WLMs) and liquid crystals (LCs) were then formulated and characterized. The transition from spherical micelles to WLMs/LCs at different oil contents was identified and compared with phase transitions predicted via the HLD-NAC model. FINDINGS The spherical micelle to branched WLM/LC transition in surfactant + oil systems coincided with the water-continuous (Type I) to bicontinuous (Type III) microemulsion phase transition predicted with the HLD-NAC model. Using this finding, the transition of commercial-grade sodium laureth sulfate (SLES) micelles to viscoelastic LCs containing various oils was predicted using the HLD-NAC. The HLD-NAC also predicted the presence of a secondary peak in viscosity obtained in "salt curves" experiments associated with branched WLMs and LCs.
Collapse
Affiliation(s)
- Francis Choi
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Ruixu Chen
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Edgar J Acosta
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada.
| |
Collapse
|
10
|
Choi F, Acosta EJ. Oil-induced formation of branched wormlike micelles in an alcohol propoxysulfate extended surfactant system. SOFT MATTER 2018; 14:8378-8389. [PMID: 30310914 DOI: 10.1039/c8sm01673a] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The addition of oil to an extended surfactant-water system (sodium tetrapropylene glycol (2-ethyl)octyl ether sulfate, C10PO4SO4Na) induces the elongation of spherical micelles into oil-swollen branched wormlike micelles (WLMs) near the phase inversion point of the surfactant-oil-water (SOW) system. The hydrophilic-lipophilic-difference (HLD) framework, which has been associated with surfactant curvature, was successfully used to predict the conditions under which WLMs are produced for both polar and non-polar oils. At HLD = 0, the formation of low-curvature surfactant structures including WLMs and liquid crystals are favored in water-rich systems. Micellar growth begins around HLD = -0.5, and reaches a plateau upon the formation of a branched WLM network at HLD = 0. Above the entanglement concentration, the branched WLMs exhibit Maxwell and shear thinning behavior which is suitable for the suspension of nanoparticles, among others.
Collapse
Affiliation(s)
- Francis Choi
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada.
| | - Edgar J Acosta
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada.
| |
Collapse
|
11
|
Danov KD, Kralchevsky PA, Stoyanov SD, Cook JL, Stott IP, Pelan EG. Growth of wormlike micelles in nonionic surfactant solutions: Quantitative theory vs. experiment. Adv Colloid Interface Sci 2018; 256:1-22. [PMID: 29804690 DOI: 10.1016/j.cis.2018.05.006] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 05/15/2018] [Accepted: 05/16/2018] [Indexed: 11/25/2022]
Abstract
Despite the considerable advances of molecular-thermodynamic theory of micelle growth, agreement between theory and experiment has been achieved only in isolated cases. A general theory that can provide self-consistent quantitative description of the growth of wormlike micelles in mixed surfactant solutions, including the experimentally observed high peaks in viscosity and aggregation number, is still missing. As a step toward the creation of such theory, here we consider the simplest system - nonionic wormlike surfactant micelles from polyoxyethylene alkyl ethers, CiEj. Our goal is to construct a molecular-thermodynamic model that is in agreement with the available experimental data. For this goal, we systematized data for the micelle mean mass aggregation number, from which the micelle growth parameter was determined at various temperatures. None of the available models can give a quantitative description of these data. We constructed a new model, which is based on theoretical expressions for the interfacial-tension, headgroup-steric and chain-conformation components of micelle free energy, along with appropriate expressions for the parameters of the model, including their temperature and curvature dependencies. Special attention was paid to the surfactant chain-conformation free energy, for which a new more general formula was derived. As a result, relatively simple theoretical expressions are obtained. All parameters that enter these expressions are known, which facilitates the theoretical modeling of micelle growth for various nonionic surfactants in excellent agreement with the experiment. The constructed model can serve as a basis that can be further upgraded to obtain quantitative description of micelle growth in more complicated systems, including binary and ternary mixtures of nonionic, ionic and zwitterionic surfactants, which determines the viscosity and stability of various formulations in personal-care and house-hold detergency.
Collapse
|
12
|
Huang C, Liu D, Wei J, Yu B, Zhang H, Cheng J. Direct numerical simulation of surfactant solution flow in the wide‐rib rectangular grooved channel. AIChE J 2018. [DOI: 10.1002/aic.16156] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Chonghai Huang
- State Key Laboratory of Multiphase Flow in Power EngineeringXi'an Jiaotong UniversityXi'an, 710049 China
| | - Dongjie Liu
- State Key Laboratory of Multiphase Flow in Power EngineeringXi'an Jiaotong UniversityXi'an, 710049 China
| | - Jinjia Wei
- State Key Laboratory of Multiphase Flow in Power EngineeringXi'an Jiaotong UniversityXi'an, 710049 China
- School of Chemical Engineering and TechnologyXi'an Jiaotong UniversityXi'an, 710049 China
| | - Bo Yu
- School of Mechanical EngineeringBeijing Institute of Petrochemical TechnologyBeijing, 102617 China
| | - Hongna Zhang
- School of Energy Science and EngineeringHarbin Institute of TechnologyHarbin, 150001 China
| | - Jianping Cheng
- School of Energy Science and EngineeringHarbin Institute of TechnologyHarbin, 150001 China
| |
Collapse
|
13
|
Dhakal S, Sureshkumar R. Anomalous diffusion and stress relaxation in surfactant micelles. Phys Rev E 2017; 96:012605. [PMID: 29347138 DOI: 10.1103/physreve.96.012605] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Indexed: 06/07/2023]
Abstract
We investigate the mechanisms of anomalous diffusion in cationic surfactant micelles using molecular dynamics simulations in the presence of explicit salt and solvent-mediated interactions. Simulations show that when the counterion density increases, saddle-shaped branched interfaces manifest. In experiments, branched structures exhibit lower viscosity as compared to linear and wormlike micelles. This has long been attributed to stress relaxation arising from the sliding motion of branches along the main chain. Our simulations reveal a mechanism of branch motion resulting from an enhanced counterion condensation at the branched interfaces and provide quantitative evidence of stress relaxation facilitated by branched sliding. Furthermore, depending on the surfactant and salt concentrations, which in turn determine the microstructure, we observe normal, subdiffusive, and superdiffusive motions of surfactants. Specifically, superdiffusive behavior is associated with branch sliding, breakage and recombination of micelle fragments, as well as constraint release in entangled systems.
Collapse
Affiliation(s)
- Subas Dhakal
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, USA
| | - Radhakrishna Sureshkumar
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, USA and Department of Physics, Syracuse University, Syracuse, New York 13244, USA
| |
Collapse
|
14
|
Huang C, Wei J. EXPERIMENTAL STUDY ON THE COLLABORATIVE DRAG REDUCTION PERFORMANCE OF A SURFACTANT SOLUTION IN GROOVED CHANNELS. BRAZILIAN JOURNAL OF CHEMICAL ENGINEERING 2017. [DOI: 10.1590/0104-6632.20170341s20150232] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
15
|
Dalba G. Peter J. W. Debye - a whole life devoted to science. ACTA CRYSTALLOGRAPHICA A-FOUNDATION AND ADVANCES 2016; 72:591-607. [PMID: 27809199 DOI: 10.1107/s2053273316013619] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 08/24/2016] [Indexed: 11/10/2022]
Abstract
In 1915 P. Debye, one of the most prominent scientists in the field of condensed-matter physics and physical chemistry, published an X-ray scattering equation for randomly oriented scattering sites. This formula, since then used for describing the structure of powders, liquids and gases, has become a model for material analysis at the nanoscale. This paper re-examines briefly Debye's works on the origin and evolution of the scattering equation and its first uses. The career of the great scientist and some of his other numerous and diverse contributions to science are also reviewed. Additionally the paper addresses aspects of his life as a teacher, as a science manager and as a man, including the recent controversy about his conduct during the Third Reich regime.
Collapse
Affiliation(s)
- Giuseppe Dalba
- Department of Physics, University of Trento, Via Sommarive 14, Trento, 38123, Italy
| |
Collapse
|
16
|
Huang C, Liu D, Wei J. Experimental study on drag reduction performance of surfactant flow in longitudinal grooved channels. Chem Eng Sci 2016. [DOI: 10.1016/j.ces.2016.06.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
17
|
Marakis J, Wunderlich K, Klapper M, Vlassopoulos D, Fytas G, Müllen K. Strong Physical Hydrogels from Fibrillar Supramolecular Assemblies of Poly(ethylene glycol) Functionalized Hexaphenylbenzenes. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b00528] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- J. Marakis
- FORTH, Institute of Electronic Structure & Laser, N. Plastira 100, 70013, Heraklion, Greece
- Department of Materials Science & Technology, University of Crete, P.O. Box 2208, 71003 Heraklion, Greece
| | - K. Wunderlich
- Max Planck
Institute
for Polymer Research, Ackermannweg
10, 55128, Mainz, Germany
| | - M. Klapper
- Max Planck
Institute
for Polymer Research, Ackermannweg
10, 55128, Mainz, Germany
| | - D. Vlassopoulos
- FORTH, Institute of Electronic Structure & Laser, N. Plastira 100, 70013, Heraklion, Greece
- Department of Materials Science & Technology, University of Crete, P.O. Box 2208, 71003 Heraklion, Greece
| | - G. Fytas
- FORTH, Institute of Electronic Structure & Laser, N. Plastira 100, 70013, Heraklion, Greece
- Department of Materials Science & Technology, University of Crete, P.O. Box 2208, 71003 Heraklion, Greece
- Max Planck
Institute
for Polymer Research, Ackermannweg
10, 55128, Mainz, Germany
| | - K. Müllen
- Max Planck
Institute
for Polymer Research, Ackermannweg
10, 55128, Mainz, Germany
| |
Collapse
|
18
|
Dhakal S, Sureshkumar R. Uniaxial Extension of Surfactant Micelles: Counterion Mediated Chain Stiffening and a Mechanism of Rupture by Flow-Induced Energy Redistribution. ACS Macro Lett 2015. [DOI: 10.1021/acsmacrolett.5b00761] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Subas Dhakal
- Department of Biomedical and Chemical Engineering and ‡Department of Physics, Syracuse University, Syracuse, New York 13244, United States
| | - Radhakrishna Sureshkumar
- Department of Biomedical and Chemical Engineering and ‡Department of Physics, Syracuse University, Syracuse, New York 13244, United States
| |
Collapse
|
19
|
Sarkar P, Chattopadhyay A. Micellar dipole potential is sensitive to sphere-to-rod transition. Chem Phys Lipids 2015; 195:34-8. [PMID: 26616562 DOI: 10.1016/j.chemphyslip.2015.11.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Revised: 11/16/2015] [Accepted: 11/17/2015] [Indexed: 12/31/2022]
Abstract
Structural transitions involving shape changes play an important role in cellular physiology. Charged micelles offer a convenient model system in which structural transitions can be suitably induced by increasing the ionic strength of the medium. In this paper, we have explored sphere-to-rod transition in charged micelles of SDS and CTAB by monitoring micellar dipole potential using the dual wavelength ratiometric approach utilizing the potential-sensitive membrane probe di-8-ANEPPS. Our results show that micellar dipole potential is sensitive to sphere-to-rod transition in charged micelles. Micellar dipole potential exhibited increase with increasing ionic strength (salt), irrespective of the nature of micellar charge, implying considerable dipolar reorganization underlying structural transitions. We interpret the increase in dipole potential due to sphere-to-rod transition because of an increase in the population of confined (nonrandom) dipoles induced by micellar organizational change. This is due to the fact that dipole potential arises due to the nonrandom arrangement of micellar dipoles and water molecules at the micelle interface. Our results constitute one of the first reports describing drastic dipolar reorganization due to micellar shape (and size) change. We envision that dipole potential measurements could provide novel insights into micellar processes that are associated with dipolar reorganization.
Collapse
Affiliation(s)
- Parijat Sarkar
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
| | | |
Collapse
|
20
|
Dhakal S, Sureshkumar R. Topology, length scales, and energetics of surfactant micelles. J Chem Phys 2015; 143:024905. [DOI: 10.1063/1.4926422] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Affiliation(s)
- Subas Dhakal
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, USA
| | - Radhakrishna Sureshkumar
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, USA
- Department of Physics, Syracuse University, Syracuse, New York 13244, USA
| |
Collapse
|
21
|
Effects of some anions of the Hofmeister series on the rheology of cetyltrimethylammonium-salicylate wormlike micelles. Colloids Surf A Physicochem Eng Asp 2015. [DOI: 10.1016/j.colsurfa.2015.01.052] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
22
|
Zhang Y, An P, Liu X. A “worm”-containing viscoelastic fluid based on single amine oxide surfactant with an unsaturated C22-tail. RSC Adv 2015. [DOI: 10.1039/c4ra16772d] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A “worm”-containing viscoelastic fluid based on single unsaturated C22-tailed amine oxide surfactant shows pH-controlled thermo-thickening behaviour.
Collapse
Affiliation(s)
- Yongmin Zhang
- Key Laboratory of Food Colloids and Biotechnology Ministry of Education
- School of Chemical & Materials Engineering
- Jiangnan University
- 214122 Wuxi
- People's Republic of China
| | - Pengyun An
- Key Laboratory of Food Colloids and Biotechnology Ministry of Education
- School of Chemical & Materials Engineering
- Jiangnan University
- 214122 Wuxi
- People's Republic of China
| | - Xuefeng Liu
- Key Laboratory of Food Colloids and Biotechnology Ministry of Education
- School of Chemical & Materials Engineering
- Jiangnan University
- 214122 Wuxi
- People's Republic of China
| |
Collapse
|
23
|
Kamranfar P, Jamialahmadi M. Effect of surfactant micelle shape transition on the microemulsion viscosity and its application in enhanced oil recovery processes. J Mol Liq 2014. [DOI: 10.1016/j.molliq.2014.07.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
24
|
Daful AG, Mackie AD. Micellar morphological transformations for a series of linear diblock model surfactants. J Chem Phys 2014; 140:104905. [DOI: 10.1063/1.4867894] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
25
|
Basu A, Ghosh SK, Saha R, Nandi R, Ghosh T, Saha B. Effect of Some Non Functional Surfactants and Electrolytes on the Hexavalent Chromium Reduction by Glycerol: A Mechanistic Study. TENSIDE SURFACT DET 2013. [DOI: 10.3139/113.110152] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Hexavalent chromium is a widespread environmental contaminant and a known human carcinogen. Kinetics of reduction of hexavalent chromium by bio-molecule glycerol in micellar media have been studied spectrophotometrically. The cytoplasmic reduction of hexavalent chromium to trivalent chromium occurs in micro-heterogeneous systems. In vitro, the micelles are considered to mimic the cellular membranes. The electron transfer processes occurring in the micellar systems is considered as model to obtain insight into the electron transport process prevailing in biological systems. Micellar media is also a probe to establish the mechanistic paths of reduction of hexavalent chromium to trivalent chromium. Effects of electrolytes common to biological system are studied to establish the proposed reaction mechanism strongly.
Collapse
Affiliation(s)
- A. Basu
- Department of Chemistry, The University Burdwan, Golapbag, Burdwan, WB, India, 713104
| | - S. K. Ghosh
- Department of Chemistry, The University Burdwan, Golapbag, Burdwan, WB, India, 713104
| | - R. Saha
- Department of Chemistry, The University Burdwan, Golapbag, Burdwan, WB, India, 713104
| | - R. Nandi
- Department of Chemistry, The University Burdwan, Golapbag, Burdwan, WB, India, 713104
| | - T. Ghosh
- Department of Chemistry, A.B.N. Seal College, Coochbehar, WB, India, 736101
| | - B. Saha
- Department of Chemistry, The University Burdwan, Golapbag, Burdwan, WB, India, 713104
| |
Collapse
|
26
|
Abstract
A major scientific challenge of the past decade pertaining to the field of soft matter has been to craft 'adaptable' materials, inspired by nature, which can dynamically alter their structure and functionality on demand, in response to triggers produced by environmental changes. Amongst these, 'smart' surfactant wormlike micelles, responsive to external stimuli, are a particularly recent area of development, yet highly promising, given the versatility of the materials but simplicity of the design-relying on small amphiphilic molecules and their spontaneous self-assembly. The switching 'on' and 'off' of the micellar assembly structures has been reported using electrical, optical, thermal or pH triggers and is now envisaged for multiple stimuli. The structural changes, in turn, can induce major variations in the macroscopic characteristics, affecting properties such as viscosity and elasticity and sometimes even leading to a spontaneous and effective 'sol-gel' transition. These original smart materials based on wormlike micelles have been successfully used in the oil industry, and offer a significant potential in a wide range of other technological applications, including biomedicine, cleaning processes, drag reduction, template synthesis, to name but a few. This review will report results in this field published over the last few years, describe the potential and practical applications of stimuli-responsive wormlike micelles and point out future challenges.
Collapse
Affiliation(s)
- Zonglin Chu
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, PR China
| | | | | |
Collapse
|
27
|
Landazuri G, Fernandez VVA, Soltero JFA, Rharbi Y. Kinetics of the sphere-to-rod like micelle transition in a pluronic triblock copolymer. J Phys Chem B 2012; 116:11720-7. [PMID: 22934621 DOI: 10.1021/jp3009089] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The kinetics of the sphere-to-rod transition was studied in aqueous micelle solutions of triblock copolymer poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) pluronic P103 (PEO(17)PPO(60)PEO(17)). This transition was triggered by a temperature jump from the sphere phase to the rod phase and monitored with dynamic light scattering. The combination of the scattering intensity and the hydrodynamic radius were used to show that the micelles grow steadily as rods throughout the growth process. The transition was found to exhibit a single exponential behavior even in the case of large deviations from equilibrium. The linear increase in the decay rate with increasing copolymer concentration shows that the transition is dominated by a mechanism involving fusion and fragmentation of proper micelles. The decays of the sphere-to-rod transition were simulated for two pathways: random fusion fragmentation and successive addition of spherical micelles to rods. We show that micelle growth most likely occurs via random fusion-fragmentation. The second order rate constant for fusion and the fragmentation rate are calculated for the case of random fusion-fragmentation.
Collapse
Affiliation(s)
- Gabriel Landazuri
- Laboratoire de Rhéologie, UJF/INPG/CNRS, UMR 5520, B.P.53, F-38041 Grenoble Cedex 9, France
| | | | | | | |
Collapse
|
28
|
Lin CA, Wu CR, Tsai HC. Synthesis of ultra-high-molecular-weight PVA using two-stage photo-concentrated emulsion polymerization of vinyl acetate. Des Monomers Polym 2012. [DOI: 10.1163/156855506777351027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
29
|
Daful AG, Avalos JB, Mackie AD. Model shape transitions of micelles: spheres to cylinders and disks. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:3730-3743. [PMID: 22292910 DOI: 10.1021/la204132c] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We present a microscopic analysis of shape transitions of micelles of model linear nonionic surfactants. In particular, symmetric H(4)T(4) and asymmetric H(3)T(6) surfactants have been chosen for the study. In a previous work, it has been observed that symmetric surfactants have a strong tendency to prefer spherical micelles over a wide range of chemical potentials, while asymmetric surfactants undergo shape transitions between a spherical micelle at low concentration to other forms, mainly finite cylindrical micelles. This study combines the application of a two-dimensional single-chain mean-field theory (SCMFT) with Monte Carlo (MC) simulations of exactly the same systems. On the one hand, the characteristics of the SCMFT make this method suitable for free energy calculations, especially for small surfactants, due to the incorporation of relevant microscopic details in the model. On the other hand, MC simulations permit us to obtain a complete picture of the statistical mechanical problem, for the purpose of validation of the mean-field calculations. Our results reveal that the spherical shape for the symmetric surfactant is stable over a large range of surfactant concentrations. However, the asymmetric surfactant undergoes a complex shape transition that we have followed by calculating the standard chemical potential as a function of the aggregation number. The results indicate that the system forms prolate spheroids prior to developing short capped cylinders that gradually grow in length, with some oscillations in the energy of formation. The most important result of our work is the evidence of a bifurcation where, together with the elongated objects, the system can develop oblate aggregates and finally a torus shape similar to a red blood cell.
Collapse
Affiliation(s)
- Asfaw Gezae Daful
- Departament d'Enginyeria Química, ETSEQ, Universitat Rovira i Virgili, Av. dels Països Catalans 26, 43007 Tarragona, Spain
| | | | | |
Collapse
|
30
|
Chakraborty T, Chakraborty I, Ghosh S. The methods of determination of critical micellar concentrations of the amphiphilic systems in aqueous medium. ARAB J CHEM 2011. [DOI: 10.1016/j.arabjc.2010.06.045] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
|
31
|
|
32
|
ELWORTHY PH, MACFARLANE CB. Further aspects of the physical chemistry of some non-ionic detergents. J Pharm Pharmacol 2011; 17:129-43. [PMID: 14296935 DOI: 10.1111/j.2042-7158.1965.tb07632.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
33
|
Trap HJL, Hermans JJ. Light-scattering by a number of solvents, in conjunction with data on solutions of Ludox, saccharose-octa-acetate, and polystyrene. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/recl.19540730302] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
34
|
Mehta SK, Sharma S, Mehta N, Cameotra SS. Biomimetic amphiphiles: properties and potential use. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 672:102-20. [PMID: 20545277 DOI: 10.1007/978-1-4419-5979-9_8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
Surfactants are the amphiphilic molecules that tend to alter the interfacial and surface tension. The fundamental property related to the structure of surfactant molecules is their self-aggregation resulting in the formation of association colloids. Apart from the packing of these molecules into closed structures, the structural network also results in formation of extended bilayers, which are thermodynamically stable and lead to existence of biological membranes and vesicles. From biological point of view the development of new knowledge and techniques in the area of vesicles, bilayers and multiplayer membranes and their polymerizable analogue provide new opportunities for research in the respective area. 'Green Surfactants' or the biologically compatible surfactants are in demand to replace some of the existing surfactants and thereby reduce the environmental impact, in general caused by classic surfactants. In this context, the term 'natural surfactants or biosurfactants' is often used to indicate the natural origin of the surfactant molecules. Most important aspect of biosurfactants is their environmental acceptability, because they are readily biodegradable and have low toxicity than synthetic surfactants. Some of the major applications of biosurfactants in pollution and environmental control are microbial enhanced oil recovery, hydrocarbon degradation, hexa-chloro cyclohexane (HCH) degradation and heavy-metal removal from contaminated soil. In this chapter, we tried to make a hierarchy from vital surfactant molecules toward understanding their behavioral aspects and application potential thereby ending into the higher class of broad spectrum 'biosurfactants'. Pertaining to the budding promise offered by these molecules, the selection of the type and size of each structural moiety enables a delicate balance between surface activity and biological function and this represents the most effective approach of harnessing the power of molecular self-assembly.
Collapse
Affiliation(s)
- S K Mehta
- Center of Advanced Studies in Chemistry, Chemistry Department, Panjab University, Chandigarh 160014, India.
| | | | | | | |
Collapse
|
35
|
Hatlee MD, Kozak JJ, Grätzel M. On the Interplay between Geometry and Mobility in Intramicellar Kinetics. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19820860213] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
36
|
Baumgardt K, Klar G, Strey R. On the Concentration Dependence of the Mean Aggregation Number of Ionic Micelles as Determined by Stopped-Flow Experiments. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19820861008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
37
|
|
38
|
Block Copolymer Surfactant Mixtures in Aqueous Solution: Can we Achieve Size and Shape Control by Co-Micellization? ADVANCES IN POLYMER SCIENCE 2010. [DOI: 10.1007/12_2010_66] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
|
39
|
Temperature sensitivity of wormlike micelles in poly(oxyethylene) surfactant solution: Importance of hydrophilic-group size. J Colloid Interface Sci 2009; 336:335-44. [DOI: 10.1016/j.jcis.2009.03.040] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Revised: 03/25/2009] [Accepted: 03/25/2009] [Indexed: 11/23/2022]
|
40
|
Vlachy N, Drechsler M, Touraud D, Kunz W. Anion specificity influencing morphology in catanionic surfactant mixtures with an excess of cationic surfactant. CR CHIM 2009. [DOI: 10.1016/j.crci.2008.10.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
41
|
Lerouge S, Berret JF. Shear-Induced Transitions and Instabilities in Surfactant Wormlike Micelles. POLYMER CHARACTERIZATION 2009. [DOI: 10.1007/12_2009_13] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
42
|
Orts Gil G, Losik M, Schlaad H, Drechsler M, Hellweg T. Properties of pH-responsive mixed aggregates of polystyrene-block-poly(L-lysine) and nonionic surfactant in solution and adsorbed at a solid surface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:12823-12828. [PMID: 18925753 DOI: 10.1021/la8017562] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Poly(styrene) 388- block-poly( l-lysine) 138 could be dispersed in water with the aid of the nonionic surfactant C 12E 6. Light scattering and direct imaging techniques show that the copolymer/surfactant aggregates are polydisperse spherical micelles. The rather broad size distribution can be attributed to the glassy state of the polystyrene core of the micelles hampering equilibration. Nevertheless, the poly( l-lysine) block remains pH sensitive in these mixed aggregates and circular dichroism measurements show that poly( l-lysine) block adopts a random coil conformation at low pH and an beta-sheet conformation at pH > or = 11 without any change in the micellar shape. Samples prepared by evaporation of drops of the solutions on graphite wafers exhibit different wetting patterns depending on the polypeptide conformation as indicated by atomic force microscopy.
Collapse
Affiliation(s)
- Guillermo Orts Gil
- Stranski-Laboratorium fur Physikalische and Theoretische Chemie, Institut fur Chemie, Technische Universitat Berlin, Strasse des 17 Juni 124, 10623 Berlin, Germany
| | | | | | | | | |
Collapse
|
43
|
Treki MS, Shojaei AH, Vasavada RC. Effect of Steareth-20 on the Release of Nitrofurantoin from Propylene Glycol Monostearate Microspheres. Drug Dev Ind Pharm 2008. [DOI: 10.3109/03639049709149800] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
44
|
|
45
|
Small angle neutron scattering measurements of aggregation behaviour of mixed micelles of conventional surfactants with triblock polymer L64. Colloids Surf A Physicochem Eng Asp 2008. [DOI: 10.1016/j.colsurfa.2008.05.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
46
|
Dreiss CÃCA. Wormlike micelles: where do we stand? Recent developments, linear rheology and scattering techniques. SOFT MATTER 2007; 3:956-970. [PMID: 32900044 DOI: 10.1039/b705775j] [Citation(s) in RCA: 555] [Impact Index Per Article: 32.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Wormlike micelles are elongated flexible self-assembly structures formed by the aggregation of amphiphiles. Above a threshold concentration, they entangle into a dynamic network, reminiscent of polymer solutions, and display remarkable visco-elastic properties, which have been exploited in numerous industrial and technological fields. Relating the microstructure of these intricate structures with their bulk properties is still an ongoing quest. In this review, we present a classification of wormlike micelles, with a focus on novel systems and applications. We describe the current state of understanding of their linear rheology and give a detailed account of recent progress in small-angle neutron scattering, a particularly powerful technique to elucidate their microstructure on a wide range of length-scales.
Collapse
Affiliation(s)
- CÃ Cile A Dreiss
- Pharmaceutical Science Research Division, King's College London, Franklin-Wilkins Building, 150 Stamford Street, London, UKSE1 9NH
| |
Collapse
|
47
|
Hayes ME, El-Emary M, Schechter RS, Wade WH. SURFACE TENSION AND SELECTED MICELLAR SOLUTION THERMODYNAMIC PROPERTIES OF SOME N,N-BIS-(2-HYDR0XYETHYL) AMIDES. J DISPER SCI TECHNOL 2007. [DOI: 10.1080/01932698008962173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
48
|
Nakamura K, Shikata T. Threadlike micelle formation of anionic surfactants in aqueous solution. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2006; 22:9853-9. [PMID: 17106973 DOI: 10.1021/la061031w] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
We have investigated the formation of threadlike micelles consisting of anionic surfactants and certain additives in aqueous solution. Threadlike micelles long enough to be entangled with each other were formed in a clear aqueous solution of two anionic surfactants, sodium hexadecyl sulfate and sodium tetradecyl sulfate. These solutions also contained pentylammonium bromides or p-toluidine halides and exhibited remarkable viscoelasticity. Because the molar ratio of surfactants to cationic additives in these micelles seemed close to unity, they formed 1:1 stoichiometric complexes between surfactant anions and additive cations, as previously found in systems of cationic surfactants such as hexadecyltrimethylammonium bromide and sodium salicylate. The viscoelastic behavior of these anionic threadlike micellar systems was adequately described by a simple Maxwell element with a single relaxation time and strength, as in many similar cationic systems.
Collapse
Affiliation(s)
- Kenji Nakamura
- Department of Macromolecular Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | | |
Collapse
|
49
|
Panchal KN, Desai A, Nagar T. Sphere‐to‐Rod Transitions in Cationic Micelles: Quaternary Ammonium Halides+Phenol+Water Systems. J DISPER SCI TECHNOL 2006. [DOI: 10.1080/01932690600766900] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
50
|
Khalil RA. A new approach to micellization parameters using iterative mathematical method. Colloids Surf A Physicochem Eng Asp 2006. [DOI: 10.1016/j.colsurfa.2006.02.063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|