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Ochoa C, Gao S, Xu C, Srivastava S, Sharma V. Foam film stratification, viscosity, and small-angle X-ray scattering of micellar SDS solutions over an extended concentration range (1< c/CMC < 75). SOFT MATTER 2024; 20:1922-1934. [PMID: 38323381 DOI: 10.1039/d3sm01069d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2024]
Abstract
Ultrathin foam films (thickness, h < 100 nm) containing micelles undergo drainage via stratification manifested as coexisting thick-thin flat regions, nanoscopic non-flat topography, and the stepwise decrease in film thickness that yields a characteristic step-size. Most studies characterize the variation in step size and stratification kinetics in micellar foam films in a limited concentration range, c/CMC < 12.5 (c < 100 mM). Likewise, most scattering studies characterize micelle dimensions, intermicellar distance, and volume fraction in bulk aqueous SDS solutions in this limited concentration range. In this contribution, we show drainage via stratification can be observed for concentrations up to c/CMC < 75 (c < 600 mM). Understanding the stratification behavior of freely draining micellar films with sodium dodecyl sulfate (SDS) concentration varying in the range 10 mM ≤ cSDS ≤ 600 mM is essential for molecular engineering, consumer product formulations, and controlling foaming in industrial processes. Here, we visualize and analyze nanoscopic thickness variations and transitions in stratifying foam films using Interferometry Digital Imaging Optical Microscopy (IDIOM) protocols. We compare step size obtained from foam stratification to micelle dimension, micelle volume fraction, and intermicellar distance obtained from small angle X-ray scattering studies. Even though the volume fraction increases and approaches 25% at c = 600 mM, the solution viscosity only increases by a factor of four compared to the solvent, consistent with the findings from both stratification and scattering studies. These comparisons allow us to explore the effect of micelle size, morphology, and intermicellar interactions on supramolecular oscillatory structural disjoining pressure, which influences the stratification behavior of draining foam films containing micelles under confinement.
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Affiliation(s)
- Chrystian Ochoa
- Department of Chemical Engineering, University of Illinois Chicago, 929 W Taylor St, Chicago, IL 60607, USA.
| | - Shang Gao
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Chenxian Xu
- Department of Chemical Engineering, University of Illinois Chicago, 929 W Taylor St, Chicago, IL 60607, USA.
| | - Samanvaya Srivastava
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Center for Biological Physics, University of California, Los Angeles, Los Angeles, CA 90095, USA
- Institute for Carbon Management, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Vivek Sharma
- Department of Chemical Engineering, University of Illinois Chicago, 929 W Taylor St, Chicago, IL 60607, USA.
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2
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Hassan L, Xu C, Boehm M, Baier SK, Sharma V. Ultrathin Micellar Foam Films of Sodium Caseinate Protein Solutions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:6102-6112. [PMID: 37074870 DOI: 10.1021/acs.langmuir.3c00192] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Sodium caseinates (NaCas), derived from milk proteins called caseins, are often added to food formulations as emulsifiers, foaming agents, and ingredients for producing dairy products. In this contribution, we contrast the drainage behavior of single foam films made with micellar NaCas solutions with well-established features of stratification observed for the micellar sodium dodecyl sulfate (SDS) foam films. In reflected light microscopy, the stratified SDS foam films display regions with distinct gray colors due to differences in interference intensity from coexisting thick-thin regions. Using IDIOM (interferometry digital imaging optical microscopy) protocols we pioneered for mapping nanotopography of foam films, we showed that drainage via stratification in SDS films proceeds by the expansion of flat domains that are thinner than surrounding by a concentration-dependent step-size, and nonflat features (nanoridges and mesas) form at the moving front. Furthermore, stratifying SDS foam films show stepwise thinning, such that the step-size and terminal film thickness decrease with concentration. Here we visualize the nanotopography in protein films with high spatiotemporal resolution using IDIOM protocols to address two long-standing questions. Do protein foam films formulated with NaCas undergo drainage via stratification? Are thickness transitions and variations in protein foam films determined by intermicellar interactions and supramolecular oscillatory disjoining pressure? In contrast with foam films containing micellar SDS, we find that micellar NaCas foam films display just one step, nonflat and noncircular domains that expand without forming nanoridges and a terminal thickness that increases with NaCas concentration. We infer that the differences in adsorbing and self-assembling unimers triumph over any similarities in the structure and interactions of their micelles.
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Affiliation(s)
- Lena Hassan
- Department of Chemical Engineering, University of Illinois Chicago, 929 West Taylor Street, Chicago, Illinois 60607, United States
| | - Chenxian Xu
- Department of Chemical Engineering, University of Illinois Chicago, 929 West Taylor Street, Chicago, Illinois 60607, United States
| | - Michael Boehm
- Motif Foodworks, 27 Drydock Avenue, Boston, Massachusetts 02210, United States
| | - Stefan K Baier
- Motif Foodworks, 27 Drydock Avenue, Boston, Massachusetts 02210, United States
- School of Chemical Engineering, The University of Queensland, Brisbane, 4072 Queensland, Australia
| | - Vivek Sharma
- Department of Chemical Engineering, University of Illinois Chicago, 929 West Taylor Street, Chicago, Illinois 60607, United States
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3
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Xu C, Martínez Narváez CDV, Kotwis P, Sharma V. Polymer-Surfactant Complexes Impact the Stratification and Nanotopography of Micellar Foam Films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:5761-5770. [PMID: 37040267 DOI: 10.1021/acs.langmuir.3c00024] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Freestanding films of soft matter drain via stratification due to confinement-induced structuring and layering of supramolecular structures such as micelles. Neutral polymers, added as rheology modifiers to cosmetics, foods, pharmaceuticals, and petrochemical formulations, often interact with monomers and micelles of surfactants, forming polymer-surfactant complexes. Despite many studies that explore interfacial and bulk rheological properties, the corresponding influence of polymer-surfactant complexes on foam drainage and lifetime is not well understood and motivates this study. Here, we report the discovery and evidence of drainage via stratification in foam films formed with polymer-surfactant (PEO-SDS) complexes. We show that the stratification trifecta of coexisting thick-thin regions, stepwise thinning, and nanoscopic topological features such as nanoridges and mesas can be observed using IDIOM (interferometry, digital imaging, and optical microscopy) protocols we developed for nanoscopic thickness mapping. We determine that for polymer concentrations below overlap concentration and surfactant concentrations beyond the excess micelle point, polymer-surfactant complexation impact the nanoscopic topography but not the step size, implying the amplitude of disjoining pressure changes, but periodicity remains unchanged.
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Affiliation(s)
- Chenxian Xu
- Department of Chemical Engineering, University of Illinois Chicago, 929 W. Taylor Street, Chicago, Illinois 60607, United States
| | - Carina D V Martínez Narváez
- Department of Chemical Engineering, University of Illinois Chicago, 929 W. Taylor Street, Chicago, Illinois 60607, United States
| | - Patrycja Kotwis
- Department of Chemical Engineering, University of Illinois Chicago, 929 W. Taylor Street, Chicago, Illinois 60607, United States
| | - Vivek Sharma
- Department of Chemical Engineering, University of Illinois Chicago, 929 W. Taylor Street, Chicago, Illinois 60607, United States
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4
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Wierenga PA, Basheva ES, Delahaije RJBM. Variations in foam collapse and thin film stability with constant interfacial and bulk properties. Adv Colloid Interface Sci 2023; 312:102845. [PMID: 36709573 DOI: 10.1016/j.cis.2023.102845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 01/20/2023] [Accepted: 01/20/2023] [Indexed: 01/24/2023]
Abstract
The stability of foams is commonly linked to the interfacial properties of the proteins and other surfactants used. This study aimed to use these relationships to explain differences in foam stability observed among similar beer samples from different breweries. The foam stability was different for each sample (Nibem foam stability ranged from 206 to 300 s), but ranking was similar for all three foaming methods used, thus independent of the method, gas, etc. Differences in foam stability were dominated by differences in coalescence, as illustrated by the correlation with the stability of single bubbles and thin liquid films. The differences in coalescence stability could not be explained by the measured interfacial properties (e.g. surface pressure, adsorption rate, dilatational modulus and surface shear viscosity), or the bulk properties (concentration, pH, ionic strength, viscosity), since they were similar for all samples. The drainage rates and disjoining pressure isotherms measured in thin liquid films were also similar for all samples, further limiting the options to explain the differences in foam stability using known arguments. The differences in coalescence stability of the thin films was shown to depend on the liquid in between the adsorbed layers of the thin film, using a modified capillary cell to exchange this liquid (to a buffer, or one of the other samples). This illustrates the need to review our current understanding and to develop new methods both for experimental study and theoretical description, to better understand foam stability in the future.
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Affiliation(s)
- Peter Alexander Wierenga
- Laboratory of Food Chemistry, Wageningen UR, Bornse Weilanden 9, Wageningen 6708, WG, the Netherlands.
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5
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Ritacco HA. Polyelectrolyte/Surfactant Mixtures: A Pathway to Smart Foams. ACS OMEGA 2022; 7:36117-36136. [PMID: 36278099 PMCID: PMC9583308 DOI: 10.1021/acsomega.2c05739] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Accepted: 09/26/2022] [Indexed: 05/10/2023]
Abstract
This review deals with liquid foams stabilized by polyelectrolyte/surfactant (PS) complexes in aqueous solution. It briefly reviews all the important aspects of foam physics at several scales, from interfaces to macroscopic foams, needed to understand the basics of these complex systems, focusing on those particular aspects of foams stabilized by PS mixtures. The final section includes a few examples of smart foams based on PS complexes that have been reported recently in the literature. These PS complexes open an opportunity to develop new intelligent dispersed materials with potential in many fields, such as oil industry, environmental remediation, and pharmaceutical industry, among others. However, there is much work to be done to understand the mechanism involved in the stabilization of foams with PS complexes. Understanding those underlying mechanisms is vital to successfully formulate smart systems. This review is written in the hope of stimulating further work in the physics of PS foams and, particularly, in the search for responsive foams based on polymer-surfactant mixtures.
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6
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Gao S, Ochoa C, Sharma V, Srivastava S. Salt Weakens Intermicellar Interactions and Structuring in Bulk Solutions and Foam Films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:11003-11014. [PMID: 36044777 DOI: 10.1021/acs.langmuir.2c01592] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Drainage via stratification in micellar foam films formulated with ionic surfactants shows dramatic changes on salt addition: both the step size and the number of steps in their stepwise thinning diminish. As the stratification process is governed by supramolecular oscillatory structural forces that arise due to confinement-induced structuring of micelles, it is apparent that salt addition reduces the magnitude, periodicity, and decay length of the oscillatory forces. In this contribution, we characterize the changes in micellar size, shape, and interactions on salt addition in bulk solutions using small-angle X-ray scattering (SAXS) to understand and elucidate the influence of salt on stratification in micellar foam films and, more broadly, on the oscillatory structural forces. Adding salt leads to a significant reduction in long-range correlations between micelles and smaller intermicellar distances. These effects manifest as a weakening of the primary peak of the structure factor, ascertained from SAXS spectra, accompanied by its shift to higher wave vectors. Weakened long-range correlations diminish the magnitude and periodicity of the oscillatory disjoining pressure leading to smaller step sizes, fewer steps, and a rich nanoscopic topography, due to the influence of disjoining pressure on the deformable interfaces. The step sizes in stratifying thin films and intermicellar distances in bulk solutions present incongruous values, implying an imperfect analogy with studies on charged nanoparticles with matched and salt concentration-independent values of measured interparticle distances that equal the periodicity of force-distance curves. We anticipate that our findings are significant for multicomponent soft and biological matter containing self-assembled supramolecular structures wherein screened Coulomb interactions govern the self-assembly, interfacial adsorption, interactions, dynamics, and stability.
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Affiliation(s)
- Shang Gao
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, California 90095, United States
| | - Chrystian Ochoa
- Department of Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60608, United States
| | - Vivek Sharma
- Department of Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60608, United States
| | - Samanvaya Srivastava
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, California 90095, United States
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, California 90095, United States
- Center for Biological Physics, University of California, Los Angeles, Los Angeles, California 90095, United States
- Institute for Carbon Management, University of California, Los Angeles, Los Angeles, California 90095, United States
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7
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Andrieux S, Patil M, Jacomine L, Hourlier-Fargette A, Heitkam S, Drenckhan W. Investigating pore-opening in hydrogel foams at the scale of free-standing thin films. Macromol Rapid Commun 2022; 43:e2200189. [PMID: 35579423 DOI: 10.1002/marc.202200189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 04/21/2022] [Indexed: 11/08/2022]
Abstract
Controlling the pore connectivity of polymer foams is key for most of their applications, ranging from liquid uptake, mechanics, and acoustic/thermal insulation to tissue engineering. Despite its importance, the scientific phenomena governing the pore-opening processes remain poorly understood, requiring tedious trial-and-error procedures for property optimisation. This lack of understanding is partly explained by the high complexity of the different interrelated, multi-scale processes which take place as the foam transforms from an initially fluid foam into a solid foam. To progress in this field, we take inspiration from long-standing research on liquid foams and thin films to develop model experiments in a microfluidic "Thin Film Pressure Balance". These experiments allow us to investigate isolated thin films under well-controlled environmental conditions reproducing those arising within a foam undergoing cross-linking and drying. Using the example of alginate hydrogel films, we correlate the evolution of isolated thin films undergoing gelation and drying with the evolution of the rheological properties of the same alginate solution in bulk. We introduce the overall approach and use a first set of results to propose a starting point for the phenomenological description of the different types of pore-opening processes and the classification of the resulting pore-opening types. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- S Andrieux
- Université de Strasbourg, CNRS, Institut Charles Sadron UPR22, Strasbourg, F-67000, France
| | - M Patil
- Université de Strasbourg, CNRS, Institut Charles Sadron UPR22, Strasbourg, F-67000, France
| | - L Jacomine
- Université de Strasbourg, CNRS, Institut Charles Sadron UPR22, Strasbourg, F-67000, France
| | - A Hourlier-Fargette
- Université de Strasbourg, CNRS, Institut Charles Sadron UPR22, Strasbourg, F-67000, France
| | - S Heitkam
- Institute of Process Engineering and Environmental Technology, TU Dresden, 01062, Dresden, Germany
| | - W Drenckhan
- Université de Strasbourg, CNRS, Institut Charles Sadron UPR22, Strasbourg, F-67000, France
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8
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Ochoa C, Xu C, Martínez Narváez CDV, Yang W, Zhang Y, Sharma V. Drainage via stratification and nanoscopic thickness transitions of aqueous sodium naphthenate foam films. SOFT MATTER 2021; 17:8915-8924. [PMID: 34545906 DOI: 10.1039/d1sm01169c] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Sodium naphthenates (NaNs), found in crude oils and oil sands process-affected water (OSPW), can act as surfactants and stabilize undesirable foams and emulsions. Despite the critical impact of soap-like NaNs on the formation, properties, and stability of petroleum and OSPW foams, there is a significant lack of studies that characterize foam film drainage, motivating this study. Here, we contrast the drainage of aqueous foam films formulated with NaN with foams containing sodium dodecyl sulfate (SDS), a well-studied surfactant system, in the relatively low concentration regime (c/CMC < 12.5). The foam films exhibit drainage via stratification, displaying step-wise thinning and coexisting thick-thin regions manifested as distinct shades of gray in reflected light microscopy due to thickness-dependent interference intensity. Using IDIOM (interferometry digital imaging optical microscopy) protocols that we developed, we analyze pixel-wise intensity to obtain thickness maps with high spatiotemporal resolution (thickness <1 nm, lateral ∼500 nm, time ∼10 ms). The analysis of interference intensity variations over time reveals that the aqueous foam films of both SDS and NaN possess an evolving, dynamic, and rich nanoscopic topography. The nanoscopic thickness transitions for stratifying SDS foam films are attributed to the role played by damped supramolecular oscillatory structural disjoining pressure contributed by the confinement-induced layering of spherical micelles. In comparison with SDS, we find smaller concentration-dependent step size and terminal film thickness values for NaN, implying weaker intermicellar interactions and oscillatory structural disjoining pressure with shorter decay length and periodicity.
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Affiliation(s)
- Chrystian Ochoa
- Department of Chemical Engineering, University of Illinois at Chicago, Chicago, IL, USA.
| | - Chenxian Xu
- Department of Chemical Engineering, University of Illinois at Chicago, Chicago, IL, USA.
| | | | - William Yang
- Department of Chemical Engineering, University of Illinois at Chicago, Chicago, IL, USA.
| | - Yiran Zhang
- Department of Chemical Engineering, University of Illinois at Chicago, Chicago, IL, USA.
| | - Vivek Sharma
- Department of Chemical Engineering, University of Illinois at Chicago, Chicago, IL, USA.
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9
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Abstract
Ultrathin foam films containing supramolecular structures like micelles in bulk and adsorbed surfactant at the liquid-air interface undergo drainage via stratification. At a fixed surfactant concentration, the stepwise decrease in the average film thickness of a stratifying micellar film yields a characteristic step size that also describes the quantized thickness difference between coexisting thick-thin flat regions. Even though many published studies claim that step size equals intermicellar distance obtained using scattering from bulk solutions, we found no reports of a direct comparison between the two length scales. It is well established that step size is inversely proportional to the cubic root of surfactant concentration but cannot be estimated by adding micelle size to Debye length, as the latter is inversely proportional to the square root of surfactant concentration. In this contribution, we contrast the step size obtained from analysis of nanoscopic thickness variations and transitions in stratifying foam films using Interferometry Digital Imaging Optical Microscopy (IDIOM) protocols, that we developed, with the intermicellar distance obtained using small-angle X-ray scattering. We find that stratification driven by the confinement-induced layering of micelles within the liquid-air interfaces of a foam film provides a sensitive probe of non-DLVO (Derjaguin-Landau-Verwey-Overbeek) supramolecular oscillatory structural forces and micellar interactions.
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10
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Rondepierre G, Lequeux F, Verneuil E, Passade-Boupat N, Talini L. Spinodal stratification in micellar films between oil and silica. Phys Rev E 2021; 103:052801. [PMID: 34134263 DOI: 10.1103/physreve.103.052801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 04/19/2021] [Indexed: 11/07/2022]
Abstract
We report on the thinning mechanisms of supported films of surfactant (nTAB) solutions above the critical micellar concentration. The films are formed by pressing an oil drop immersed in an aqueous surfactant solution on a silica surface. Depending on the length of the carbon chain of the surfactant and its concentration, two modes of destabilization of the stratified films are observed. The first one proceeds by heterogeneous nucleation, characterized by the lateral expansion of the domain of lower thickness as evidenced long ago in suspended micellar films. In addition, the simultaneous stepwise thinning of several domains, called spinodal stratification, is observed here in supported films. We measure the time evolution of the thickness of the films, and we discuss the selection mechanism of each destabilization mode.
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Affiliation(s)
- Gaëlle Rondepierre
- Laboratoire Sciences et Ingénierie de la Matière Molle, ESPCI Paris, PSL University, Sorbonne Université, CNRS UMR 7615, F-75005 Paris, France; Laboratoire Physico-Chimie des Interfaces Complexes, ESPCI Paris, 10 rue Vauquelin, F-75231 Paris, France; and TOTAL SA, Pôle dEtudes et Recherche de Lacq, Boîte Postale 47, 64170 Lacq, France
| | - François Lequeux
- Laboratoire Sciences et Ingénierie de la Matire Molle, ESPCI Paris, PSL University, Sorbonne Université, CNRS UMR 7615, F-75005 Paris, France and Laboratoire Physico-Chimie des Interfaces Complexes, ESPCI Paris, 10 rue Vauquelin, F-75231 Paris, France
| | - Emilie Verneuil
- Laboratoire Sciences et Ingénierie de la Matire Molle, ESPCI Paris, PSL University, Sorbonne Université, CNRS UMR 7615, F-75005 Paris, France and Laboratoire Physico-Chimie des Interfaces Complexes, ESPCI Paris, 10 rue Vauquelin, F-75231 Paris, France
| | - Nicolas Passade-Boupat
- Laboratoire Physico-Chimie des Interfaces Complexes, Bâtiment CHEMSTARTUP, Route Dpartementale 817, 64170 Lacq, France and TOTAL SA, Pôle dEtudes et Recherche de Lacq, Boîte Postale 47, 64170 Lacq, France
| | - Laurence Talini
- CNRS, Surface du Verre et Interfaces, Saint-Gobain, 93300 Aubervilliers, France
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11
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Nikoubashman A. Ordering, phase behavior, and correlations of semiflexible polymers in confinement. J Chem Phys 2021; 154:090901. [DOI: 10.1063/5.0038052] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Affiliation(s)
- Arash Nikoubashman
- Institute of Physics, Johannes Gutenberg University Mainz, Staudingerweg 7, 55128 Mainz, Germany
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12
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Andrieux S, Muller P, Kaushal M, Macias Vera NS, Bollache R, Honorez C, Cagna A, Drenckhan W. Microfluidic thin film pressure balance for the study of complex thin films. LAB ON A CHIP 2021; 21:412-420. [PMID: 33349822 DOI: 10.1039/d0lc00974a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Investigations of free-standing liquid films enjoy an increasing popularity due to their relevance for many fundamental and applied scientific problems. They constitute soap bubbles and foams, serve as membranes for gas transport or as model membranes in biophysics. More generally, they provide a convenient tool for the investigation of numerous fundamental questions related to interface- and confinement-driven effects in soft matter science. Several approaches and devices have been developed in the past to characterise reliably the thinning and stability of such films, which were commonly created from low-viscosity, aqueous solutions/dispersions. With an increasing interest in the investigation of films made from strongly viscoelastic and complex fluids that may also solidify, the development of a new generation of devices is required to manage reliably the constraints imposed by these formulations. We therefore propose here a microfluidic chip design which allows for the reliable creation, control and characterisation of free-standing films of complex fluids. We provide all technical details and we demonstrate the device functioning for a larger range of systems via a selection of illustrative examples, including films of polymer melts and gelling hydrogels.
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Affiliation(s)
- Sébastien Andrieux
- Université de Strasbourg, CNRS, Institut Charles Sadron UPR22, F-67000, Strasbourg, France.
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13
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Gao M, He M, Xing R, Wang X, Wang Z. Borate-modified carbon dots as a probe for quercetin in plants. Analyst 2021; 146:590-596. [DOI: 10.1039/d0an01898h] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Schematic presentation of the PBA-CDs enhancing the fluorescence of quercetin in contrast to N-CDs.
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Affiliation(s)
- Mei Gao
- School of Chemistry Sciences
- University of Chinese Academy of Sciences
- Beijing
- China
| | - Man He
- School of Chemistry Sciences
- University of Chinese Academy of Sciences
- Beijing
- China
| | - Rang Xing
- School of Chemistry Sciences
- University of Chinese Academy of Sciences
- Beijing
- China
| | - Xuefei Wang
- School of Chemistry Sciences
- University of Chinese Academy of Sciences
- Beijing
- China
| | - Zhuo Wang
- State Key Laboratory of Chemical Resource Engineering
- College of Science
- Beijing Advanced Innovation Centre for Soft Matter Science and Engineering
- Beijing University of Chemical Technology
- Beijing
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14
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Basheva ES, Kralchevsky PA, Danov KD, Stanimirova RD, Shaw N, Petkov JT. Vortex in liquid films from concentrated surfactant solutions containing micelles and colloidal particles. J Colloid Interface Sci 2020; 576:345-355. [DOI: 10.1016/j.jcis.2020.05.048] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 05/13/2020] [Accepted: 05/14/2020] [Indexed: 11/30/2022]
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15
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Smith AM, Borkovec M, Trefalt G. Forces between solid surfaces in aqueous electrolyte solutions. Adv Colloid Interface Sci 2020; 275:102078. [PMID: 31837508 DOI: 10.1016/j.cis.2019.102078] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 10/11/2019] [Accepted: 11/18/2019] [Indexed: 11/15/2022]
Abstract
This review addresses experimental findings obtained with direct force measurements between two similar or dissimilar solid surfaces in aqueous electrolyte solutions. Interpretation of these measurements is mainly put forward in terms of the classical theory of Derjaguin, Landau, Verwey, and Overbeek (DLVO). This theory invokes a superposition of attractive van der Waals forces and repulsive double layer forces. DLVO theory is shown to be extremely reliable, even in the case of multivalent ions. However, such a description is only successful, when appropriate surface charge densities, charge regulation characteristics, and ion pairing or complexation equilibria in solution are considered. Deviations from DLVO theory only manifest themselves at distances of typically below few nm. More long-ranged non-DLVO forces can be observed in some situations, particularly, in concentrated electrolyte solutions, in the presence of strongly adsorbed layers, or for hydrophobic surfaces. The latter forces probably originate from patch-charge surface heterogeneities, which can be induced by ion-ion correlation effects, charge fluctuations, or other types of surface heterogeneities.
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Affiliation(s)
- Alexander M Smith
- Department of Inorganic and Analytical Chemistry, University of Geneva, Sciences II, 30 Quai Ernest-Ansermet, 1205 Geneva, Switzerland
| | - Michal Borkovec
- Department of Inorganic and Analytical Chemistry, University of Geneva, Sciences II, 30 Quai Ernest-Ansermet, 1205 Geneva, Switzerland
| | - Gregor Trefalt
- Department of Inorganic and Analytical Chemistry, University of Geneva, Sciences II, 30 Quai Ernest-Ansermet, 1205 Geneva, Switzerland.
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16
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Stanimirova RD, Kralchevsky PA, Danov KD, Xu H, Ung YW, Petkov JT. Oil drop deposition on solid surfaces in mixed polymer-surfactant solutions in relation to hair- and skin-care applications. Colloids Surf A Physicochem Eng Asp 2019. [DOI: 10.1016/j.colsurfa.2019.05.044] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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17
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Properties of the micelles of sulfonated methyl esters determined from the stepwise thinning of foam films and by rheological measurements. J Colloid Interface Sci 2019; 538:660-670. [PMID: 30572230 DOI: 10.1016/j.jcis.2018.12.034] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Revised: 12/09/2018] [Accepted: 12/10/2018] [Indexed: 11/24/2022]
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18
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Zhang Y, Sharma V. Thickness-Dependent Phase Transition Drives Nanoridge-to-Mesa Instability in Micellar Freestanding Films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:7922-7931. [PMID: 29863880 DOI: 10.1021/acs.langmuir.8b01010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Understanding fluxes and instabilities within freestanding ultrathin films is necessary for a better understanding of, and control over, the stability and lifetime of foams and emulsions. In micellar foam films, confinement-induced layering of micelles leads to stepwise thinning or stratification that occurs by the expansion of thinner, darker domains. Often, because of a nanoridge-to-mesa instability, one or more brighter white spots or "mesas" appear at the circular moving front between thinner domains and the thicker (less dark) surrounding film. Previous studies assume that the instability and the appearance of white spots are similar to the capillarity-driven Rayleigh instability that leads to the breakup of a coherent liquid jet. Using the IDIOM (interferometry digital imaging optical microscopy) protocols we recently developed, we characterize the nanoridge-to-mesa instability with exquisite spatiotemporal resolution (thickness <1 nm, time <1 ms). The instability could be classified as a Rayleigh instability if a similar sequence of thick and thin undulations is visualized around the expanding domains. However, quantitative analysis reveals that only mesas grow in size after the instability, whereas the rest of the nanoridge preserves its shape. By analogy to the phase separation into compositionally distinct regions, we show that the spontaneous nucleation of thicker mesas in stratifying films is a phase transition driven by the oscillatory nature of the free-energy functional.
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Affiliation(s)
- Yiran Zhang
- Department of Chemical Engineering , University of Illinois at Chicago , Chicago , Illinois 60607 , United States
| | - Vivek Sharma
- Department of Chemical Engineering , University of Illinois at Chicago , Chicago , Illinois 60607 , United States
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19
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Jiang W, Yang S, Lu W, Gao B, Xu L, Sun X, Jiang D, Xu HJ, Ma M, Cao F. A novel fluorescence “turn off-on” nano-sensor for detecting Cu2+ and Cysteine in living cells. J Photochem Photobiol A Chem 2018. [DOI: 10.1016/j.jphotochem.2018.05.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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20
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Yilixiati S, Rafiq R, Zhang Y, Sharma V. Influence of Salt on Supramolecular Oscillatory Structural Forces and Stratification in Micellar Freestanding Films. ACS NANO 2018; 12:1050-1061. [PMID: 29314826 DOI: 10.1021/acsnano.7b05391] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Freestanding films of soft matter containing micelles, nanoparticles, polyelectrolyte-surfactant complexes, bilayers, and smectic liquid crystals exhibit stratification. Stepwise thinning and coexisting thick-thin regions associated with drainage via stratification are attributed to the confinement-induced structuring and layering of supramolecular structures, which contribute supramolecular oscillatory structural forces. In freestanding micellar films, formed by a solution of an ionic surfactant above its critical micelle concentration, both interfacial adsorption and the micelle size and shape are determined by the concentration of surfactant and of added electrolytes. Although the influence of surfactant concentration on stratification has been investigated before, the influence of added salt, at concentrations typically found in water used on a daily basis, has not been investigated yet. In this contribution, we elucidate how the addition of salt affects stepwise thinning: step size, number of steps, as well as the shape and size of nanoscopic nonflat structures such as mesas in micellar foam films formed with aqueous solutions of anionic surfactant (sodium dodecyl sulfate (SDS)). The nanoscopic thickness variations and transitions are visualized and analyzed using IDIOM (Interferometry Digital Imaging Optical Microscopy) protocols with exquisite spatiotemporal resolution (thickness ∼1 nm, time <1 ms). In contrast to nanoparticle dispersions that show no influence of salt on step size, we find that the addition of salt to micellar freestanding films results in a decrease in step size as well as the number of stepwise transitions, in addition to changes in nucleation and growth of mesas, all driven by the corresponding change in supramolecular oscillatory structural forces.
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Affiliation(s)
- Subinuer Yilixiati
- Chemical Engineering, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Rabees Rafiq
- Chemical Engineering, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Yiran Zhang
- Chemical Engineering, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Vivek Sharma
- Chemical Engineering, University of Illinois at Chicago , Chicago, Illinois 60607, United States
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21
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Zhang Y, Sharma V. Nanoridge Formation and Dynamics of Stratification in Micellar Freestanding Films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:1208-1217. [PMID: 28753314 DOI: 10.1021/acs.langmuir.7b01871] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Controlling and predicting the stability and lifetime of freestanding films, including foam and emulsion films, is crucial for many industrial and biological applications. Freestanding films (thickness <100 nm), stabilized by surfactants above the critical micelle concentration, exhibit stratification or stepwise thinning. Stratification proceeds by formation of thinner domains that grow at the expense of surrounding films. In this Article, we address several longstanding challenges related to the experimental characterization and theoretical description of thickness variations, forces, fluxes and flows underlying stratification. We show that nanoridges form and grow at the moving front around expanding domains, and we visualize their shape evolution using Interferometry Digital Imaging Optical Microscopy (IDIOM) protocols with an unprecedented spatiotemporal resolution (thickness <10 nm, time <1 ms). We develop a theoretical model for drainage via stratification under the influence of supramolecular oscillatory surface forces arising from the confinement-induced layering of micelles, and we show that the nanoridge growth and domain expansion dynamics can be modeled quantitatively.
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Affiliation(s)
- Yiran Zhang
- Department of Chemical Engineering, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Vivek Sharma
- Department of Chemical Engineering, University of Illinois at Chicago , Chicago, Illinois 60607, United States
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22
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Gelli R, Del Buffa S, Tempesti P, Bonini M, Ridi F, Baglioni P. Multi-scale investigation of gelatin/poly(vinyl alcohol) interactions in water. Colloids Surf A Physicochem Eng Asp 2017. [DOI: 10.1016/j.colsurfa.2017.07.049] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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23
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Zhang Y, Yilixiati S, Pearsall C, Sharma V. Nanoscopic Terraces, Mesas, and Ridges in Freely Standing Thin Films Sculpted by Supramolecular Oscillatory Surface Forces. ACS NANO 2016; 10:4678-83. [PMID: 27057959 DOI: 10.1021/acsnano.6b01012] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Freely standing thin liquid films containing supramolecular structures including micelles, nanoparticles, polyelectrolyte-surfactant complexes, and smectic liquid crystals undergo drainage via stratification. The layer-by-layer removal of these supramolecular structures manifests as stepwise thinning over time and a coexistence of domains and nanostructures of discretely different thickness. The layering of supramolecular structures in confined thin films contributes additional non-DLVO, supramolecular oscillatory surface forces to disjoining pressure, thus influencing both drainage kinetics and stability of thin films. Understanding and characterizing the spontaneous creation and evolution of nanoscopic topography of stratifying, freely standing thin liquid films have been long-standing challenges due to the absence of experimental techniques with the requisite spatial (thickness <10 nm) and temporal resolution (<1 ms). Using Interferometry Digital Imaging Optical Microscopy (IDIOM) protocols developed herein, we visualize and characterize size, shape, and evolution kinetics of nanoscopic mesas, terraces, and ridges. The exquisite thickness maps created using IDIOM protocols provide much needed and unprecedented insights into the role of supramolecular oscillatory surface forces in driving growth of such nanostructures as well as in controlling properties and stability of freely standing thin films and, more generally, of colloidal dispersions like foams.
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Affiliation(s)
- Yiran Zhang
- Department of Chemical Engineering, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Subinuer Yilixiati
- Department of Chemical Engineering, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Collin Pearsall
- Department of Chemical Engineering, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Vivek Sharma
- Department of Chemical Engineering, University of Illinois at Chicago , Chicago, Illinois 60607, United States
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24
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Gaillard T, Poulard C, Voisin T, Honorez C, Davidson P, Drenckhan W, Roché M. Stable Freestanding Thin Films of Copolymer Melts Far from the Glass Transition. ACS Macro Lett 2015; 4:1144-1148. [PMID: 26527410 PMCID: PMC4614272 DOI: 10.1021/acsmacrolett.5b00535] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2015] [Accepted: 09/15/2015] [Indexed: 11/30/2022]
Abstract
![]()
Thin
polymer films have attracted attention because of both their
broad range of applications and of the fundamental questions they
raise regarding the dynamic response of confined polymers. These films
are unstable if the temperature is above their glass transition temperature Tg. Here, we describe freestanding thin films
of centimetric dimensions made of a comb copolymer melt far from its
glass transition that are stable for more than a day. These long lifetimes
allowed us to characterize the drainage dynamics and the thickness
profile of the films. Stratified regions appear as the film drains.
We have evidence that the stability, thinning dynamics, and thickness
profile of the films result from structural forces in the melt. Understanding
the key mechanisms behind our observations may lead to new developments
in polymeric thin films, foams, and emulsions without the use of stabilizing
agents.
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Affiliation(s)
- T. Gaillard
- Laboratoire
de Physique des Solides, CNRS UMR 8502 and Université Paris Sud, Bâtiment 510, 91405 Orsay Cedex, France
| | - C. Poulard
- Laboratoire
de Physique des Solides, CNRS UMR 8502 and Université Paris Sud, Bâtiment 510, 91405 Orsay Cedex, France
| | - T. Voisin
- Laboratoire
de Physique des Solides, CNRS UMR 8502 and Université Paris Sud, Bâtiment 510, 91405 Orsay Cedex, France
| | - C. Honorez
- Laboratoire
de Physique des Solides, CNRS UMR 8502 and Université Paris Sud, Bâtiment 510, 91405 Orsay Cedex, France
| | - P. Davidson
- Laboratoire
de Physique des Solides, CNRS UMR 8502 and Université Paris Sud, Bâtiment 510, 91405 Orsay Cedex, France
| | - W. Drenckhan
- Laboratoire
de Physique des Solides, CNRS UMR 8502 and Université Paris Sud, Bâtiment 510, 91405 Orsay Cedex, France
| | - M. Roché
- Laboratoire
de Physique des Solides, CNRS UMR 8502 and Université Paris Sud, Bâtiment 510, 91405 Orsay Cedex, France
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25
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Herman D, Walz JY. Forces and force-scaling in systems of adsorbing nanoparticles as measured using colloidal probe atomic force microscopy. Colloids Surf A Physicochem Eng Asp 2015. [DOI: 10.1016/j.colsurfa.2015.04.053] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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26
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Silica nanoparticle suspensions under confinement of thin liquid films. J Colloid Interface Sci 2015; 449:522-9. [DOI: 10.1016/j.jcis.2015.02.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 02/06/2015] [Accepted: 02/06/2015] [Indexed: 01/01/2023]
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27
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Herman D, Walz JY. Effects of metal oxide nanoparticles on the stability of dispersions of weakly charged colloids. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:4844-4852. [PMID: 25860256 DOI: 10.1021/acs.langmuir.5b00745] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The stability behavior of dispersions of weakly charged silica colloids was studied in the presence of highly charged metal oxide nanoparticles. Experiments were performed using 5 nm zirconia as well as 10 nm alumina nanoparticles (both positively charged), which were added to 0.1 vol % suspensions of 1.0 μm silica microparticles at the silica IEP. Both types of nanoparticles provided effective stabilization of the silica; i.e., the silica suspensions were stabilized for longer than the observation period (greater than 12 h). Stability was observed at zirconia concentrations as low as 10(-4) vol % and at an alumina concentration of 10(-2) vol %. The nanoparticles adsorbed onto the microparticle surfaces (confirmed via SEM imaging), which increased the zeta-potential of the silica. Force profile measurements performed with colloidal probe atomic force microscopy showed that the adsorption was effectively irreversible.
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Affiliation(s)
- David Herman
- †Department of Chemical Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - John Y Walz
- ‡Department of Chemical and Materials Engineering, University of Kentucky, Lexington, Kentucky 40506, United States
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28
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Browne C, Tabor RF, Grieser F, Dagastine RR. Direct AFM force measurements between air bubbles in aqueous monodisperse sodium poly(styrene sulfonate) solutions. J Colloid Interface Sci 2015; 451:69-77. [PMID: 25881266 DOI: 10.1016/j.jcis.2015.03.050] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 03/26/2015] [Accepted: 03/27/2015] [Indexed: 01/06/2023]
Abstract
Structural forces play an important role in the rheology, processing and stability of colloidal systems and complex fluids, with polyelectrolytes representing a key class of structuring colloids. Here, we explore the interactions between soft colloids, in the form of air bubbles, in solutions of monodisperse sodium poly(styrene sulfonate) as a model polyelectrolyte. It is found that by self-consistently modelling the force oscillations due to structuring of the polymer chains along with deformation of the bubbles, it is possible to precisely predict the interaction potential between approaching bubbles. In line with polyelectrolyte scaling theory, two distinct regimes of behaviour are seen, corresponding to dilute and semi-dilute polymer solutions. It is also seen that by blending monodisperse systems to give a bidisperse sample, the interaction forces between soft colloids can be controlled with a high degree of precision. At increasing bubble collision velocity, it is revealed that hydrodynamic flow overwhelms oscillatory structural interactions, showing the important disparity between equilibrium behaviour and dynamic interactions.
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Affiliation(s)
- Christine Browne
- Particulate Fluids Processing Centre, The University of Melbourne, Parkville, Victoria 3010, Australia; School of Chemistry, The University of Melbourne, Parkville, Victoria 3010, Australia; Department of Chemical and Biomolecular Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia.
| | - Rico F Tabor
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia.
| | - Franz Grieser
- Particulate Fluids Processing Centre, The University of Melbourne, Parkville, Victoria 3010, Australia; School of Chemistry, The University of Melbourne, Parkville, Victoria 3010, Australia.
| | - Raymond R Dagastine
- Particulate Fluids Processing Centre, The University of Melbourne, Parkville, Victoria 3010, Australia; Department of Chemical and Biomolecular Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia; Melbourne Centre for Nanofabrication, Clayton, Victoria 3168, Australia.
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29
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Gochev G. Thin liquid films stabilized by polymers and polymer/surfactant mixtures. Curr Opin Colloid Interface Sci 2015. [DOI: 10.1016/j.cocis.2015.03.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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30
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Fewkes CJ, Tabor RF, Dagastine RR. Sphere to rod transitions in self assembled systems probed using direct force measurement. SOFT MATTER 2015; 11:1303-1314. [PMID: 25571867 DOI: 10.1039/c4sm02399d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The influence of nanoparticle shape, in particular the sphere to rod transition, on surface forces and consequently the properties of colloidal fluids is an interesting but not well investigated phenomenon. Here, the surface force behaviour of concentrated surfactant solutions containing cetyltrimethylammonium bromide and sodium salicylate with micelle shapes varying from slightly prolate to high aspect ratio rods was measured. Atomic force microscopy (AFM) with both rigid particle and soft droplet probes was used with comparisons and analysis made using the Chan-Dagastine-White model. It is observed that small changes to the micelle shape result in no discernable differences to the surface force behaviour, however, once the micelles are elongated significantly, the long range forces adjust in nature from oscillatory to that of a single attractive force well. This highlights the importance that nanocolloid shape has on the behaviour and properties of emulsions and other colloidal fluids, specifically for emulsion flocculation and handling in systems of rod and worm like micelles.
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Affiliation(s)
- Christopher J Fewkes
- Particulate Fluids Processing Centre, The University of Melbourne, Parkville, Victoria, 3010 Australia
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31
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Ji S, Walz JY. Depletion forces and flocculation with surfactants, polymers and particles — Synergistic effects. Curr Opin Colloid Interface Sci 2015. [DOI: 10.1016/j.cocis.2014.11.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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32
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Fauser H, von Klitzing R. Effect of polyelectrolytes on (de)stability of liquid foam films. SOFT MATTER 2014; 10:6903-16. [PMID: 25080085 DOI: 10.1039/c4sm01241k] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The review addresses the influence of polyelectrolytes on the stabilisation of free-standing liquid foam films, which affects the stability of a whole macroscopic foam. Both the composition of the film surface and the stratification of the film bulk drives the drainage and the interfacial forces within a foam film. Beside synthetic polyelectrolytes also natural polyelectrolytes like cellulose, proteins and DNA are considered.
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Affiliation(s)
- Heiko Fauser
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Institut fr Chemie, Technische Universitt Berlin, Strasse des 17.Juni 124, D-10623 Berlin, Germany.
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33
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Guzman FJ, Walz JY. Separation of colloidal particles in a packed column using depletion and structural forces. Colloids Surf A Physicochem Eng Asp 2014. [DOI: 10.1016/j.colsurfa.2014.01.073] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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34
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Razul MSG, MacDougall CJ, Hanna CB, Marangoni AG, Peyronel F, Papp-Szabo E, Pink DA. Oil binding capacities of triacylglycerol crystalline nanoplatelets: nanoscale models of tristearin solids in liquid triolein. Food Funct 2014; 5:2501-8. [DOI: 10.1039/c3fo60654f] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Polycrystalline particles composed of triacylglycerol (TAG) molecules, and their networks, in anhydrous TAG oils find extensive use as edible oils in the food industry.
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Affiliation(s)
| | | | | | - Alejandro G. Marangoni
- Guelph-Waterloo Center for Graduate Work in Physics
- Department of Food Science
- University of Guelph
- Guelph, Canada
| | - Fernanda Peyronel
- Guelph-Waterloo Center for Graduate Work in Physics
- Department of Food Science
- University of Guelph
- Guelph, Canada
| | | | - David A. Pink
- Physics Department
- St.Francis Xavier University
- Antigonish, Canada
- Guelph-Waterloo Center for Graduate Work in Physics
- Department of Food Science
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35
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James G, Walz J. Experimental and theoretical investigation of the depletion and structural forces produced by ionic micelles. Colloids Surf A Physicochem Eng Asp 2014. [DOI: 10.1016/j.colsurfa.2013.09.033] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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36
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Ji S, Walz JY. Depletion Flocculation Induced by Synergistic Effects of Nanoparticles and Polymers. J Phys Chem B 2013; 117:16602-9. [DOI: 10.1021/jp410159a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shunxi Ji
- Department of Chemical Engineering, Virginia Tech, Blacksburg, Virginia 24060, United States
| | - John Y. Walz
- Department of Chemical Engineering, Virginia Tech, Blacksburg, Virginia 24060, United States
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37
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Ji S, Walz JY. Synergistic effects of nanoparticles and polymers on depletion and structural interactions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:15159-15167. [PMID: 24279863 DOI: 10.1021/la403473g] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
An experimental study was performed to investigate the synergistic effects of two different solution components on the depletion and structural forces between colloidal particles. Using silica nanoparticles and anionic poly(acrylic acid) polymer, it was found that the depletion and structural forces measured between a 30 μm diameter silica sphere and a flat silica plate (obtained using colloidal probe atomic force microscopy) were substantially greater than the sum of the forces obtained in systems containing only nanoparticles and only polymer. This result arises because the anionic polymer chains adsorb to the nanoparticles, creating a complex that is over twice as large as either component. Although the number density of depletants decreases with such complexation, the larger size results in much greater forces at longer ranges. In addition, the measured force profiles could be well described using a force model in which all components were treated as hard, charged spheres. The results clearly indicate that predicting the depletion force in systems with multiple depletant components, such as the one used here, can be much more complicated than simply adding the forces contributed from each component independently.
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Affiliation(s)
- Shunxi Ji
- Department of Chemical Engineering, Virginia Tech , Blacksburg, Virginia 24060, United States
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38
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Herman D, Walz JY. Stabilization of weakly charged microparticles using highly charged nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:5982-94. [PMID: 23594145 DOI: 10.1021/la400699g] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
An experimental study was performed to understand the ability of highly charged nanoparticles to stabilize a dispersion of weakly charged microspheres. The experiments involved adding either anionic (sulfate) or cationic (amidine) latex nanoparticles to dispersions of micrometer-sized silica particles near the silica isoelectric point (IEP). Although both types of nanoparticles increased the zeta potential of the silica microspheres above the value at which dispersions containing only silica spheres remained stable, only with the amidine nanoparticles was stability obtained. Adsorption tests with flat silica slides showed that the amidine nanoparticles deposited in much greater numbers onto the silica, producing multilayer coverage with adsorbed particle densities that were roughly three times that obtained with the sulfate nanoparticles. A model calculating the DLVO interaction between the silica spheres in which the adsorbed nanoparticle layers were treated as a continuous film with dielectric properties between those of polystyrene and water predicted stability for both systems. It is hypothesized that the relatively low adsorption of the sulfate nanoparticles (fractional surface coverages ≤ 25%) led to patches of bare silica on the microspheres that could align during interaction due to Brownian motion. These results indicate that highly charged nanoparticles can be effective stabilizers provided the level of adsorption is sufficiently high. It was also found that the zeta potential alone is not a sufficient parameter for predicting stability of these binary systems.
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Affiliation(s)
- David Herman
- Department of Chemical Engineering, Virginia Tech, Blacksburg, Virginia 24060, United States
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39
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Ji S, Walz JY. Interaction potentials between two colloidal particles surrounded by an extremely bidisperse particle suspension. J Colloid Interface Sci 2013; 394:611-8. [DOI: 10.1016/j.jcis.2012.11.040] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 11/14/2012] [Accepted: 11/17/2012] [Indexed: 10/27/2022]
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40
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Fameau AL, Lam S, Velev OD. Multi-stimuli responsive foams combining particles and self-assembling fatty acids. Chem Sci 2013. [DOI: 10.1039/c3sc51774h] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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41
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Anachkov SE, Danov KD, Basheva ES, Kralchevsky PA, Ananthapadmanabhan KP. Determination of the aggregation number and charge of ionic surfactant micelles from the stepwise thinning of foam films. Adv Colloid Interface Sci 2012; 183-184:55-67. [PMID: 22935484 DOI: 10.1016/j.cis.2012.08.003] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Revised: 08/03/2012] [Accepted: 08/07/2012] [Indexed: 12/20/2022]
Abstract
The stepwise thinning (stratification) of liquid films, which contain micelles of an ionic surfactant, depends on the micelle aggregation number, N(agg), and charge, Z. Vice versa, from the height of the step and the final film thickness one can determine N(agg), Z, and the degree of micelle ionization. The determination of N(agg) is based on the experimental fact that the step height is equal to the inverse cubic root of the micelle concentration. In addition, Z is determined from the final thickness of the film, which depends on the concentration of counterions dissociated from the micelles in the bulk. The method is applied to micellar solutions of six surfactants, both anionic and cationic: sodium dodecylsulfate (SDS), cetyl trimethylammonium bromide (CTAB), cetylpyridinium chloride (CPC), sodium laurylethersulfates with 1 and 3 ethylene oxide groups (SLES-1EO and SLES-3EO), and potassium myristate. The method has the following advantages: (i) N(agg) and Z are determined simultaneously, from the same set of experimental data; (ii) N(agg) and Z are determined for each given surfactant concentration (i.e. their concentration dependence is obtained), and (iii) N(agg) and Z can be determined even for turbid solutions, like those of carboxylates, where the micelles coexist with acid-soap crystallites, so that the application of other methods is difficult. The results indicate that the micelles of greater aggregation number have a lower degree of ionization, which can be explained with the effect of counterion binding. The proposed method is applicable to the concentration range, in which the films stratify and the micelles are spherical. This is satisfied for numerous systems representing scientific and practical interest.
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Affiliation(s)
- Svetoslav E Anachkov
- Department of Chemical Engineering, Faculty of Chemistry and Pharmacy, Sofia University, Sofia 1164, Bulgaria
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42
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Tronson R, Tchea MF, Ashokkumar M, Grieser F. The Behavior of Acoustic Bubbles in Aqueous Solutions Containing Soluble Polymers. J Phys Chem B 2012; 116:13806-11. [DOI: 10.1021/jp308897c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Rohan Tronson
- Particulate
Fluids Processing Centre, School of Chemistry, University of Melbourne, Victoria 3010, Australia
| | - Michelle F. Tchea
- Particulate
Fluids Processing Centre, School of Chemistry, University of Melbourne, Victoria 3010, Australia
| | - Muthupandian Ashokkumar
- Particulate
Fluids Processing Centre, School of Chemistry, University of Melbourne, Victoria 3010, Australia
| | - Franz Grieser
- Particulate
Fluids Processing Centre, School of Chemistry, University of Melbourne, Victoria 3010, Australia
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43
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Giovambattista N, Rossky P, Debenedetti P. Computational Studies of Pressure, Temperature, and Surface Effects on the Structure and Thermodynamics of Confined Water. Annu Rev Phys Chem 2012; 63:179-200. [DOI: 10.1146/annurev-physchem-032811-112007] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- N. Giovambattista
- Department of Physics, Brooklyn College of the City University of New York, Brooklyn, New York 11210;
| | - P.J. Rossky
- Institute for Computational Engineering and Sciences, Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712;
| | - P.G. Debenedetti
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544-5263;
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44
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Manipulating microparticle interactions using highly charged nanoparticles. Colloids Surf A Physicochem Eng Asp 2012. [DOI: 10.1016/j.colsurfa.2011.12.040] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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45
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James GK, Walz JY. Hydrodynamic force on a microparticle approaching a wall in a nanoparticle dispersion: observation of a separation-dependent effective viscosity. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:92-103. [PMID: 22066789 DOI: 10.1021/la203782c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Colloid probe atomic force microscopy was used to measure the hydrodynamic force exerted on a 30-μm-diameter silica particle being moved toward or away from a silica plate in aqueous dispersions of 22-nm-diameter silica nanoparticles (6 or 8 vol %). Upon comparing the measured force to predictions made using the well-known expression of Cox and Brenner (Cox, R. G.; Brenner, H. Chem. Eng. Sci.1967, 22, 1753-1777) assuming a constant viscosity equal to that of the bulk dispersion, the measured drag force was found to become significantly less than that predicted at smaller particle-plate separation distances (e.g., <500 nm). A recent theoretical paper by Bhattacharya and Blawzdziewicz (Bhattacharya, S.; Blawzdziewicz, J. J. Chem. Phys.2008, 128, 214704) predicted that in a solution of dispersed nanoparticles the effective viscosity characterizing the hydrodynamic force on the particle should vary from that of the solvent at contact to that of the bulk dispersion at large separations. By adjusting the viscosity in the Cox and Brenner expression to make the predicted hydrodynamic force match that measured (i.e., the effective viscosity), a curve showing these exact characteristics was obtained. The effective viscosity profile was not a function of particle speed, and changes in the effective viscosity extended to separation distances of as large as 2 μm (nearly 100 times the hard diameter of the nanoparticles). These results suggest that in the range of typical colloidal forces (on the order of 100 nm), the dynamics of particle motion in such systems are determined by the viscosity of the solvent and not that of the bulk dispersion.
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Affiliation(s)
- Gregory K James
- Department of Chemical Engineering, Virginia Tech, 0211 Blacksburg, Virginia 24061, United States
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46
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Falkman P, Aberg C, Clemens A, Sparr E. Lyotropic lipid phases confined in cylindrical pores: structure and permeability. J Phys Chem B 2011; 115:14450-61. [PMID: 22007791 DOI: 10.1021/jp206451c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A model membrane system based on lipid lyotropic phases confined inside the pores of a well-defined scaffold membrane, thereby forming a double-porous membrane structure, is described. The model membrane system is characterized with regard to lipid structure, lipid location, and phase transitions, using small-angle X-ray scattering, differential scanning calorimetry, and confocal microscopy. The system enables studies of transport across oriented lipid bilayers as well as of lipids in confinement. The lipids are shown to be located inside the membrane pores, and the effect of confinement on lipid structure is shown to be small, although dependent on the surface properties of the scaffold membrane. For transport studies, Franz diffusion cells and different types of drugs/dyes are used, and the transport studies are complemented with theoretical modeling. Lipids investigated include monoolein, dioleoyl phosphatidylcholine, dimyristoyl phosphatidylcholine, and E. coli total lipid extract. In the case of monoolein, the lipid structure can be changed from a bicontinuous cubic Ia3d phase to a liquid crystalline lamellar phase, by controlling the osmotic pressure of the surrounding solution through addition of water-soluble polymer. The osmotic pressure can thereby be used as a switch, changing the permeability of the lipid phase up to 100-fold, depending on the properties of the diffusing substance. The large effect of changing the structure implies an alignment of the lamellar phase inside the pores.
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Affiliation(s)
- Peter Falkman
- Physical Chemistry, Chemical Center, Lund University, Lund, Sweden
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47
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Danov KD, Basheva ES, Kralchevsky PA, Ananthapadmanabhan KP, Lips A. The metastable states of foam films containing electrically charged micelles or particles: experiment and quantitative interpretation. Adv Colloid Interface Sci 2011; 168:50-70. [PMID: 21489398 DOI: 10.1016/j.cis.2011.03.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2011] [Revised: 03/13/2011] [Accepted: 03/15/2011] [Indexed: 10/18/2022]
Abstract
The stepwise thinning (stratification) of liquid films containing electrically charged colloidal particles (in our case - surfactant micelles) is investigated. Most of the results are applicable also to films from nanoparticle suspensions. The aim is to achieve agreement between theory and experiment, and to better understand the physical reasons for this phenomenon. To test different theoretical approaches, we obtained experimental data for free foam films from micellar solutions of three ionic surfactants. The theoretical problem is reduced to the interpretation of the experimental concentration dependencies of the step height and of the final film thickness. The surface charges of films and micelles are calculated by means of the charge-regulation model, with a counterion-binding (Stern) constant determined from the fit of surface tension isotherms. The applicability of three models was tested: the Poisson-Boltzmann (PB) model; the jellium-approximation (JA), and the cell model (CM). The best agreement theory/experiment was obtained with the JA model without using any adjustable parameters. Two theoretical approaches are considered. First, in the energy approach the step height is identified with the effective diameter of the charged micelles, which represents an integral of the electrostatic-repulsion energy calculated by the JA model. Second, in the osmotic approach the step height is equal to the inverse cubic root of micelle number density in the bulk of solution. Both approaches are in good agreement with the experiment if the suspension of charged particles (micelles) represents a jellium, i.e. if the particle concentration is uniform despite the field of the electric double layers. The results lead to a convenient method for determining the aggregation number of ionic surfactant micelles from the experimental heights of the steps.
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48
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Ivanov VA, Rodionova AS, An EA, Martemyanova JA, Stukan MR, Müller M, Paul W, Binder K. Orientational ordering transitions of semiflexible polymers in thin films: a Monte Carlo simulation. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 84:041810. [PMID: 22181168 DOI: 10.1103/physreve.84.041810] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Indexed: 05/31/2023]
Abstract
Athermal solutions (from dilute to concentrated) of semiflexible macromolecules confined in a film of thickness D between two hard walls are studied by means of grand-canonical lattice Monte Carlo simulation using the bond fluctuation model. This system exhibits two phase transitions as a function of the thickness of the film and polymer volume fraction. One of them is the bulk isotropic-nematic first-order transition, which ends in a critical point on decreasing the film thickness. The chemical potential at this transition decreases with decreasing film thickness ("capillary nematization"). The other transition is a continuous (or very weakly first-order) transition in the layers adjacent to the hard planar walls from the disordered phase, where the bond vectors of the macromolecules show local ordering (i.e., "preferential orientation" along the x or y axes of the simple cubic lattice, but no long-range orientational order occurs), to a quasi-two-dimensional nematic phase (with the director at each wall being oriented along either the x or y axis), while the bulk of the film is still disordered. When the chemical potential or monomer density increase, respectively, the thickness of these surface-induced nematic layers grows, causing the disappearance of the disordered region in the center of the film.
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Affiliation(s)
- V A Ivanov
- Faculty of Physics, Moscow State University, Moscow 119991, Russia
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49
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Üzüm C, Christau S, von Klitzing R. Structuring of Polyelectrolyte (NaPSS) Solutions in Bulk and under Confinement as a Function of Concentration and Molecular Weight. Macromolecules 2011. [DOI: 10.1021/ma201466a] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Cagri Üzüm
- Stranski-Laboratorium, Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 124, D-10623 Berlin, Germany
| | - Stephanie Christau
- Stranski-Laboratorium, Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 124, D-10623 Berlin, Germany
| | - Regine von Klitzing
- Stranski-Laboratorium, Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 124, D-10623 Berlin, Germany
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50
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Basheva ES, Kralchevsky PA, Christov NC, Danov KD, Stoyanov SD, Blijdenstein TBJ, Kim HJ, Pelan EG, Lips A. Unique properties of bubbles and foam films stabilized by HFBII hydrophobin. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:2382-2392. [PMID: 21319779 DOI: 10.1021/la104726w] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The HFBII hydrophobin is an amphiphilic protein that can irreversibly adsorb at the air/water interface. The formed protein monolayers can reach a state of two-dimensional elastic solid that exhibits a high mechanical strength as compared to adsorption layers of typical amphiphilic proteins. Bubbles formed in HFBII solutions preserve the nonspherical shape they had at the moment of solidification of their surfaces. The stirring of HFBII solutions leads to the formation of many bubbles of micrometer size. Measuring the electrophoretic mobility of such bubbles, the ζ-potential was determined. Upon compression, the HFBII monolayers form periodic wrinkles of wavelength 11.5 μm, which corresponds to bending elasticity k(c) = 1.1 × 10(-19) J. The wrinkled hydrophobin monolayers are close to a tension-free state, which prevents the Ostwald ripening and provides bubble longevity in HFBII stabilized foams. Films formed between two bubbles are studied by experiments in a capillary cell. In the absence of added electrolyte, the films are electrostatically stabilized. The appearance of protein aggregates is enhanced with the increase of the HFBII and electrolyte concentrations and at pH close to the isoelectric point. When the aggregate concentration is not too high (to block the film thinning), the films reach a state with 12 nm uniform thickness, which corresponds to two surface monolayers plus HFBII tetramers sandwiched between them. In water, the HFBII molecules can stick to each other not only by their hydrophobic moieties but also by their hydrophilic parts. The latter leads to the attachment of HFBII aggregates such as dimers, tetramers, and bigger ones to the interfacial adsorption monolayers, which provides additional stabilization of the liquid films.
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Affiliation(s)
- Elka S Basheva
- Department of Chemical Engineering, Faculty of Chemistry, Sofia University , 1164 Sofia, Bulgaria
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