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Pérez-González J, Muñoz-Castro Y, Rodríguez-González F, Marín-Santibáñez BM, Medina-Bañuelos EF. Influence of Sonication on the Molecular Characteristics of Carbopol ® and Its Rheological Behavior in Microgels. Gels 2024; 10:420. [PMID: 39057445 PMCID: PMC11276194 DOI: 10.3390/gels10070420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2024] [Revised: 06/21/2024] [Accepted: 06/24/2024] [Indexed: 07/28/2024] Open
Abstract
In this work, the effect of sonication on the molecular characteristics of polyacrylic acid (Carbopol® Ultrez 10), as well as on its rheological behavior in aqueous dispersions and microgels, was analyzed for the first time by rheometry, weight-average molecular weight (Mw) measurements via static light scattering (SLS), Fourier transform infrared (FTIR) spectroscopy and confocal microscopy. For this, the precursor dispersion and the microgels containing 0.25 wt.% of Ultrez 10 were sonicated in a commercial ultrasound bath at constant power and at different times. The main rheological properties of the microgel, namely, shear modulus, yield stress and viscosity, all decreased with increasing sonication time, while the microgel's Herschel-Bulkley (H-B) behavior, without thixotropy, was preserved. Also, Mw of Ultrez 10 decreased up to almost one-third (109,212 g/mol) of its original value (300,860 g/mol) after 180 min of sonication. These results evidence a softening of the gel microstructure, which results from the reduction in the Mw of polyacrylic acid with sonication time. Separately, FTIR measurements show that sonication produces scission in the C-C links of the Carbopol® backbone, which results in chains with the same chemistry but lower molecular weight. Finally, confocal microscopy observations revealed a diminution of the size of the microsponge domains and more free solvent with sonication time, which is reflected in a less compact and softer microstructure. The present results indicate that both the microstructure and the rheological behavior of Carbopol® microgels, in particular, and complex fluids, in general, may be manipulated or tailored by systematic high-power ultrasonication.
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Affiliation(s)
- José Pérez-González
- Laboratorio de Reología y Física de la Materia Blanda, Escuela Superior de Física y Matemáticas, Instituto Politécnico Nacional, U. P. Adolfo López Mateos, Ciudad de México C.P. 07738, Mexico;
| | - Yusef Muñoz-Castro
- Laboratorio de Reología y Física de la Materia Blanda, Escuela Superior de Física y Matemáticas, Instituto Politécnico Nacional, U. P. Adolfo López Mateos, Ciudad de México C.P. 07738, Mexico;
| | - Francisco Rodríguez-González
- Departamento de Biotecnología, Centro de Desarrollo de Productos Bióticos, Instituto Politécnico Nacional, Carretera Yautepec-Jojutla Km. 6, Calle CEPROBI No. 8, Col. San Isidro, Yautepec, Morelos C.P. 62731, Mexico;
| | - Benjamín M. Marín-Santibáñez
- Escuela Superior de Ingeniería Química e Industrias Extractivas, Instituto Politécnico Nacional, U. P. Adolfo López Mateos, Ciudad de México C.P. 07738, Mexico; (B.M.M.-S.); (E.F.M.-B.)
| | - Esteban F. Medina-Bañuelos
- Escuela Superior de Ingeniería Química e Industrias Extractivas, Instituto Politécnico Nacional, U. P. Adolfo López Mateos, Ciudad de México C.P. 07738, Mexico; (B.M.M.-S.); (E.F.M.-B.)
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Kavishvar D, Ramachandran A. Low yield stress measurements with a microfluidic rheometer. LAB ON A CHIP 2024; 24:3135-3148. [PMID: 38779813 DOI: 10.1039/d3lc01047c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
Yield stress, τy, is a key rheological property of complex materials such as gels, dense suspensions, and dense emulsions. While there is a range of established techniques to measure τy in the order of tens to thousands of pascals, the measurement of low τy, specifically below 1 Pa, remains underexplored. In this article, we present the measurement of low apparent τy using a Hele-Shaw microfluidic extensional flow device (MEFD). Using the MEFD, we observe a gradient in shear stress, τ, such that τ is lower near the center or stagnation point, and higher away from the stagnation point. For a yield stress fluid, we observe that, below a certain flow rate, τ exceeds τy only in the outer region, leading to stagnation or unyielding of the fluid in the inner region. We use scaling analysis based on a Hele-Shaw linear extensional flow to deduce τy by measuring the size of the unyielded region, S. We validate this scaling relationship using Carbopol solutions with concentrations ranging between 0.015 to 0.3%, measuring τy as low as ∼10 mPa to ∼1 Pa, and comparing it with τy measured using a standard rheometer. While the experimental lower limit of our technique is 5 mPa, modifying the geometry or improving the image analysis can reduce this limit to the order of 10-4 Pa. The MEFD facilitates rapid measurement of τy, allowing for its real-time assessment. We further report τy of human blood samples between 30 to 80 mPa with their hematocrit ranging between 14 to 63%. Additionally, we determine τy for a mucus simulant (∼0.7 Pa), and lactic drink (∼7 mPa) to demonstrate the versatility of the MEFD technique.
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Affiliation(s)
- Durgesh Kavishvar
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada.
| | - Arun Ramachandran
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada.
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3
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Abstract
Abstract
The review presents current research results for Carbopol-based microgels as yield-stress materials, covering three aspects: chemical, physical and rheological. Such a joint three-aspect study has no analog in the literature. The chemical aspects of Carbopol polymers are presented in terms of a cross-linking polymerization of acrylic acid, their molecular structure, microgel formulation, polyacid dissociation and neutralization, osmotic pressure and associated immense microgel swelling. The physical characterization is focused on models of the shear-induced solid-to-liquid transition of microgels, which are formed of mesoscopic particles typical for soft matter materials. Models that describe interparticle effects are presented to explain the energy states of microgel particles at the mesoscale of scrutiny. Typical representatives of the models utilize attributes of jamming dispersions, micromechanical and polyelectrolyte reactions. Selected relationships that result from the models, such as scaling rules and nondimensional flow characteristics are also presented. The rheological part presents the discussion of problems of yield stress in 2D and 3D deformations, appearance and magnitude of the wall slip. The theory and characteristics of Carbopol microgel deformation in rotational rheometers are presented with graphs for the steady-state measurements, stress-controlled oscillation and two types of transient shear deformation. The review is concluded with suggestions for future research.
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Affiliation(s)
- Zdzisław Jaworski
- Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology , Aleja Piastow 42 , 71-065 , Szczecin , Poland
| | - Tadeusz Spychaj
- Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology , Aleja Piastow 42 , 71-065 , Szczecin , Poland
| | - Anna Story
- Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology , Aleja Piastow 42 , 71-065 , Szczecin , Poland
| | - Grzegorz Story
- Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology , Aleja Piastow 42 , 71-065 , Szczecin , Poland
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Liu W, Wu J, Zhu H, He C, Ngai T. A facile evanescent-field imaging approach for monitoring colloidal gel evolution near a surface. SOFT MATTER 2021; 17:4006-4010. [PMID: 33881131 DOI: 10.1039/d1sm00331c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A facile evanescent-field imaging approach is developed to probe the aggregation behavior of near-wall colloids/clusters during colloidal gel evolution. Total internal reflection microscope (TIRM) images are directly utilized to access the structural relaxation time via density-fluctuation theory. The behaviors of cluster-cluster aggregation and physical aging of the colloidal gel networks are resolved in both time and space under fractal scaling criteria.
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Affiliation(s)
- Wei Liu
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China. and Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China and College of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou 521041, China and Department of Chemistry, The Chinese University of Hong Kong, N.T., Shatin, Hong Kong, China.
| | - Jiahao Wu
- Department of Chemistry, The Chinese University of Hong Kong, N.T., Shatin, Hong Kong, China.
| | - Hui Zhu
- College of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou 521041, China
| | - Chuanxin He
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China.
| | - To Ngai
- Department of Chemistry, The Chinese University of Hong Kong, N.T., Shatin, Hong Kong, China.
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Effect of D-Mannitol on the Microstructure and Rheology of Non-Aqueous Carbopol Microgels. MATERIALS 2021; 14:ma14071782. [PMID: 33916550 PMCID: PMC8038445 DOI: 10.3390/ma14071782] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 03/31/2021] [Accepted: 04/01/2021] [Indexed: 11/17/2022]
Abstract
D-mannitol is a common polyol that is used as additive in pharmaceutical and personal care product formulations. We investigated its effect on the microstructure and rheology of novel non-aqueous Carbopol dispersions employing traditional and time-resolved rheological analysis. We considered two types of sample, (i) fresh (i.e., mannitol completely dissolved in solution) and aged (i.e., visible in crystalline form). The analysis of the intracycle rheological transitions that were observed for different samples revealed that, when completely dissolved in solution, mannitol does not alter the rheological behaviour of the Carbopol dispersions. This highlights that the chemical similarity of the additive with the molecules of the surrounding solvent allows preserving the swollen dimension and interparticle interactions of the Carbopol molecules. Conversely, when crystals are present, a hierarchical structure forms, consisting of a small dispersed phase (Carbopol) agglomerated around a big dispersed phase (crystals). In keeping with this microstructural picture, as the concentration of Carbopol reduces, the local dynamics of the crystals gradually start to control the integrity of the microstructure. Rheologically, this results in a higher elasticity of the suspensions at infinitesimal deformations, but a fragile yielding process at intermediate strains.
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Design and evaluation of mucoadhesive in situ liposomal gel for sustained ocular delivery of travoprost using two steps factorial design. J Drug Deliv Sci Technol 2021. [DOI: 10.1016/j.jddst.2021.102333] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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7
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Graziano R, Preziosi V, Uva D, Tomaiuolo G, Mohebbi B, Claussen J, Guido S. The microstructure of Carbopol in water under static and flow conditions and its effect on the yield stress. J Colloid Interface Sci 2021; 582:1067-1074. [DOI: 10.1016/j.jcis.2020.09.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 08/13/2020] [Accepted: 09/02/2020] [Indexed: 10/23/2022]
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Agarwal M, Kaushal M, Joshi YM. Signatures of Overaging in an Aqueous Dispersion of Carbopol. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:14849-14863. [PMID: 33241688 DOI: 10.1021/acs.langmuir.0c02887] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In this work, we study the effect of the deformation field on the physical aging behavior of an aqueous Carbopol dispersion. It is composed of soft swollen particles of gel that get deformed and acquire a polygonal shape, with flat interfaces rendering the dispersion a soft solid-like consistency as filled volume fraction approaches unity. It has been proposed that owing to release of stored elastic energy in the deformed particles, Carbopol dispersion undergoes microstructural evolution that is reminiscent of physical aging in soft glassy materials. We observe that application of moderate magnitude of oscillatory strain to Carbopol dispersion slows down its relaxation dynamics, thereby showing characteristics of overaging. On the other hand, the sufficiently high magnitude of strain makes the relaxation dynamics faster, causing rejuvenation. We also solve the soft glassy rheology model, which, when subjected to the same flow field, corroborates with experimental observations on the Carbopol dispersion. This behavior, therefore, suggests that in a system of jammed soft particles of Carbopol, the particles occupying shallow energy wells upon application of moderate strain field adjust themselves in such a manner that they predominantly occupy the deeper energy wells leading to observe the overaging dynamics.
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Affiliation(s)
- Mayank Agarwal
- Department of Chemical Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Manish Kaushal
- Department of Chemical Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Yogesh M Joshi
- Department of Chemical Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
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9
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Migliozzi S, Meridiano G, Angeli P, Mazzei L. Investigation of the swollen state of Carbopol molecules in non-aqueous solvents through rheological characterization. SOFT MATTER 2020; 16:9799-9815. [PMID: 33005911 DOI: 10.1039/d0sm01196g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We explore how different types of solvent influence the rheological properties of non-aqueous Carbopol dispersions from the dilute to the jammed state. In novel non-aqueous formulations, polar solvents are used more and more frequently, because they can form Carbopol microgels without the need of any neutralizing agents. However, the swelling behaviour of Carbopol molecules in the absence of water, when ionic forces are weak, is still poorly understood. To this end, we study the swelling behaviour of Carbopol 974P NF in different polar solvents, i.e. glycerol, PEG400 and mixtures of the two solvents, by mapping the rheological behaviour of Carbopol suspensions from very dilute to highly concentrated conditions. The rheological study reveals that the onset of the jamming transition occurs at different critical polymer concentrations depending on the solvents used. Nevertheless, once the jammed state is reached, both elastic and yielding behaviours are scalable with the particle volume fraction. These results suggest that the type of solvent influences the final volume of the single Carbopol particles but does not alter the interactions between the particles. The final radius of the swollen particles is estimated from shear rheology measurements in dilute conditions, showing a decrease of the final swelling ratio of Carbopol molecules of almost 50% for PEG400 solutions, a result that confirms the shift to higher values of the critical jamming concentration obtained from linear viscoelasticity for the same solutions.
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Affiliation(s)
- Simona Migliozzi
- Department of Chemical Engineering, University College London, Torrington Place, London WC1E 7JE, UK.
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10
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Li H, Zheng K, Yang J, Zhao J. Anomalous Diffusion Inside Soft Colloidal Suspensions Investigated by Variable Length Scale Fluorescence Correlation Spectroscopy. ACS OMEGA 2020; 5:11123-11130. [PMID: 32455234 PMCID: PMC7241028 DOI: 10.1021/acsomega.0c01052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 04/24/2020] [Indexed: 06/11/2023]
Abstract
The diffusion of molecules and particles inside the aqueous suspension of soft colloids (polymer microgels) is investigated using variable length scale fluorescence correlation spectroscopy (VLS-FCS). Carbopol 940 is chosen as the model matrix system, and two factors affecting diffusion are investigated: the spatial hindrance and the diffusant-matrix interaction. By studying diffusion of molecules and particles with different sizes inside the suspension, VLS-FCS reveals the restricted motion at a short length scale, that is, in the gaps between the microgels, and normal diffusion at a larger length scale. The information on the gap's length scale is also accessed. On the other hand, by tuning the pH value, the diffusant-matrix electrostatic attraction is adjusted and the results expose a short-time fast diffusion of probe molecules inside the gaps and a long-time restricted diffusion because of trapping inside the microgels. It is proved that VLS-FCS is a powerful method, investigating anomalous diffusion at different length scales and it is a promising approach to investigate diffusion in complex soft matter systems.
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Affiliation(s)
- Hengyi Li
- Beijing
National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- The
University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kaikai Zheng
- Beijing
National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- The
University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingfa Yang
- Beijing
National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- The
University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiang Zhao
- Beijing
National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- The
University of Chinese Academy of Sciences, Beijing 100049, China
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11
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Bhattacharjee T, Datta SS. Confinement and activity regulate bacterial motion in porous media. SOFT MATTER 2019; 15:9920-9930. [PMID: 31750508 DOI: 10.1039/c9sm01735f] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Understanding how bacteria move in porous media is critical to applications in healthcare, agriculture, environmental remediation, and chemical sensing. Recent work has demonstrated that E. coli, which moves by run-and-tumble dynamics in a homogeneous medium, exhibits a new form of motility when confined in a disordered porous medium: hopping-and-trapping motility, in which cells perform rapid, directed hops punctuated by intervals of slow, undirected trapping. Here, we use direct visualization to shed light on how these processes depend on pore-scale confinement and cellular activity. We find that hopping is determined by pore-scale confinement, and is independent of cellular activity; by contrast, trapping is determined by the competition between pore-scale confinement and cellular activity, as predicted by an entropic trapping model. These results thus help to elucidate the factors that regulate bacterial motion in porous media, and could help aid the development of new models of motility in heterogeneous environments.
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Affiliation(s)
- Tapomoy Bhattacharjee
- The Andlinger Center for Energy and the Environment, Princeton University, 86 Olden Street, Princeton, NJ 08544, USA
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12
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Lidon P, Villa L, Manneville S. A mesoscale study of creep in a microgel using the acoustic radiation force. SOFT MATTER 2019; 15:2688-2702. [PMID: 30821300 DOI: 10.1039/c8sm02294a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We study the motion of a sphere of diameter 330 μm embedded in a Carbopol microgel under the effect of the acoustic radiation pressure exerted by a focused ultrasonic field. The sphere motion within the microgel is tracked using videomicroscopy and compared to conventional creep and recovery measurements performed with a rheometer. We find that under moderate ultrasonic intensities, the sphere creeps as a power law of time with an exponent α ≃ 0.2 that is significantly smaller than the one inferred from global creep measurements below the yield stress of the microgel (α ≃ 0.4). Moreover, the sphere relaxation motion after creep and the global recovery are respectively consistent with these two different exponents. By allowing a rheological characterization at the scale of the sphere with forces of the order of micronewtons, the present experiments pave the way for acoustic "mesorheology" which probes volumes and forces an intermediate between standard macroscopic rheology and classical microrheology. They also open new questions about the effects of the geometry of the deformation field and of the sphere size and surface properties on the creep behaviour of soft materials.
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Affiliation(s)
- Pierre Lidon
- Univ Lyon, Ens de Lyon, Univ Claude Bernard, CNRS, Laboratoire de Physique, F-69342 Lyon, France.
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13
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Optimization of a novel in situ gel for sustained ocular drug delivery using Box-Behnken design: In vitro, ex vivo, in vivo and human studies. Int J Pharm 2019; 554:264-275. [DOI: 10.1016/j.ijpharm.2018.11.016] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 11/07/2018] [Accepted: 11/07/2018] [Indexed: 01/05/2023]
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14
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Bhattacharjee T, Kabb CP, O'Bryan CS, Urueña JM, Sumerlin BS, Sawyer WG, Angelini TE. Polyelectrolyte scaling laws for microgel yielding near jamming. SOFT MATTER 2018; 14:1559-1570. [PMID: 29450413 DOI: 10.1039/c7sm01518f] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Micro-scale hydrogel particles, known as microgels, are used in industry to control the rheology of numerous different products, and are also used in experimental research to study the origins of jamming and glassy behavior in soft-sphere model systems. At the macro-scale, the rheological behaviour of densely packed microgels has been thoroughly characterized; at the particle-scale, careful investigations of jamming, yielding, and glassy-dynamics have been performed through experiment, theory, and simulation. However, at low packing fractions near jamming, the connection between microgel yielding phenomena and the physics of their constituent polymer chains has not been made. Here we investigate whether basic polymer physics scaling laws predict macroscopic yielding behaviours in packed microgels. We measure the yield stress and cross-over shear-rate in several different anionic microgel systems prepared at packing fractions just above the jamming transition, and show that our data can be predicted from classic polyelectrolyte physics scaling laws. We find that diffusive relaxations of microgel deformation during particle re-arrangements can predict the shear-rate at which microgels yield, and the elastic stress associated with these particle deformations predict the yield stress.
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Géraud B, Jørgensen L, Ybert C, Delanoë-Ayari H, Barentin C. Structural and cooperative length scales in polymer gels. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2017; 40:5. [PMID: 28097479 DOI: 10.1140/epje/i2017-11490-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 12/01/2016] [Indexed: 06/06/2023]
Abstract
Understanding the relationship between the material structural details, the geometrical confining constraints, the local dynamical events and the global rheological response is at the core of present investigations on complex fluid properties. In the present article, this problem is addressed on a model yield stress fluid made of highly entangled polymer gels of Carbopol which follows at the macroscopic scale the well-known Herschel-Bulkley rheological law. First, performing local rheology measurements up to high shear rates ([Formula: see text] s-1)and under confinement, we evidence unambiguously the breakdown of bulk rheology associated with cooperative processes under flow. Moreover, we show that these behaviors are fully captured with a unique cooperativity length [Formula: see text] over the whole range of experimental conditions. Second, we introduce an original optical microscopy method to access structural properties of the entangled polymer gel in the direct space. Performing image correlation spectroscopy of fluorophore-loaded gels, the characteristic size D of carbopol gels microstructure is determined as a function of preparation protocol. Combining both dynamical and structural information shows that the measured cooperative length [Formula: see text] corresponds to 2-5 times the underlying structural size D, thus providing a strong grounding to the "Shear Transformation Zones" modeling approach.
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Affiliation(s)
- Baudouin Géraud
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, VILLEURBANNE, France
| | - Loren Jørgensen
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, VILLEURBANNE, France
| | - Christophe Ybert
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, VILLEURBANNE, France
| | - Hélène Delanoë-Ayari
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, VILLEURBANNE, France
| | - Catherine Barentin
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, VILLEURBANNE, France.
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16
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Sabin J, Bailey AE, Frisken BJ. Exploring the dynamics of phase separation in colloid-polymer mixtures with long range attraction. SOFT MATTER 2016; 12:5325-5333. [PMID: 27242183 DOI: 10.1039/c6sm00224b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We have studied the kinetics of phase separation and gel formation in a low-dispersity colloid - non-adsorbing polymer system with long range attraction using small-angle light scattering. This system exhibits two-phase and three-phase coexistence of gas, liquid and crystal phases when the strength of attraction is between 2 and 4kBT and gel phases when the strength of attraction is increased. For those samples that undergo macroscopic phase separation, whether to gas-crystal, gas-liquid or gas-liquid-crystal coexistence, we observe dynamic scaling of the structure factor and growth of a characteristic length scale that behaves as expected for phase separation in fluids. In samples that gel, the power law associated with the growth of the dominant length scale is not equal to 1/3, but appears to depend mainly on the strength of attraction, decreasing from 1/3 for samples near the coexistence region to 1/27 at 8kBT, over a wide range of colloid and polymer concentrations.
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Affiliation(s)
- Juan Sabin
- Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.
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17
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Jin Y, Compaan A, Bhattacharjee T, Huang Y. Granular gel support-enabled extrusion of three-dimensional alginate and cellular structures. Biofabrication 2016; 8:025016. [DOI: 10.1088/1758-5090/8/2/025016] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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18
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Lefrançois P, Ibarboure E, Payré B, Gontier E, Le Meins JF, Schatz C. Insights into Carbopol gel formulations: Microscopy analysis of the microstructure and the influence of polyol additives. J Appl Polym Sci 2015. [DOI: 10.1002/app.42761] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Pauline Lefrançois
- CNRS, LCPO; UMR 5629, F-33607 Pessac France
- University of Bordeaux, LCPO; UMR 5629, F-33607 Pessac France
| | - Emmanuel Ibarboure
- CNRS, LCPO; UMR 5629, F-33607 Pessac France
- University of Bordeaux, LCPO; UMR 5629, F-33607 Pessac France
| | - Bruno Payré
- Centre de Microscopie Electronique Appliquée à la Biologie, Faculté de Médecine Rangueil, Toulouse III, Université P. Sabatier; 31062 Toulouse France
| | - Etienne Gontier
- Bordeaux Imaging Center, UMS 3420 CNRS - Université de Bordeaux; US 4 INSERM, F-33076 Bordeaux France
| | - Jean-François Le Meins
- CNRS, LCPO; UMR 5629, F-33607 Pessac France
- University of Bordeaux, LCPO; UMR 5629, F-33607 Pessac France
| | - Christophe Schatz
- CNRS, LCPO; UMR 5629, F-33607 Pessac France
- University of Bordeaux, LCPO; UMR 5629, F-33607 Pessac France
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Kowalczyk A, Oelschlaeger C, Willenbacher N. Visualization of micro-scale inhomogeneities in acrylic thickener solutions: A multiple particle tracking study. POLYMER 2015. [DOI: 10.1016/j.polymer.2014.12.041] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Schroer MA, Gutt C, Grübel G. Characteristics of angular cross correlations studied by light scattering from two-dimensional microsphere films. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 90:012309. [PMID: 25122305 DOI: 10.1103/physreve.90.012309] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Indexed: 06/03/2023]
Abstract
Recently the analysis of scattering patterns by angular cross-correlation analysis (CCA) was introduced to reveal the orientational order in disordered samples with special focus to future applications on x-ray free-electron laser facilities. We apply this CCA approach to ultra-small-angle light-scattering data obtained from two-dimensional monolayers of microspheres. The films were studied in addition by optical microscopy. This combined approach allows to calculate the cross-correlations of the scattering patterns, characterized by the orientational correlation function Ψ(l)(q), as well as to obtain the real-space structure of the monolayers. We show that CCA is sensitive to the orientational order of monolayers formed by the microspheres which are not directly visible from the scattering patterns. By mixing microspheres of different radii the sizes of ordered monolayer domains is reduced. For these samples it is shown that Ψ(l)(q) quantitatively describes the degree of hexagonal order of the two-dimensional films. The experimental CCA results are compared with calculations based on the microscopy images. Both techniques show qualitatively similar features. Differences can be attributed to the wave-front distortion of the laser beam in the experiment. This effect is discussed by investigating the effect of different wave fronts on the cross-correlation analysis results. The so-determined characteristics of the cross-correlation analysis will be also relevant for future x-ray-based studies.
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Affiliation(s)
- M A Schroer
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany and and The Hamburg Centre for Ultrafast Imaging (CUI), Luruper Chausee 149, 22761 Hamburg, Germany
| | - C Gutt
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany and and The Hamburg Centre for Ultrafast Imaging (CUI), Luruper Chausee 149, 22761 Hamburg, Germany
| | - G Grübel
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany and and The Hamburg Centre for Ultrafast Imaging (CUI), Luruper Chausee 149, 22761 Hamburg, Germany
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Sabin J, Bailey AE, Espinosa G, Frisken BJ. Crystal-arrested phase separation. PHYSICAL REVIEW LETTERS 2012; 109:195701. [PMID: 23215400 DOI: 10.1103/physrevlett.109.195701] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Indexed: 06/01/2023]
Abstract
We have studied the interplay between phase separation and crystallization in a colloid-polymer mixture along one kinetic pathway in samples which exhibit three-phase equilibrium coexistence. In analogy with atomic systems, the range of the effective attractive interaction between colloids is sufficiently long to allow for a stable liquid phase. By direct imaging in microgravity on the International Space Station, we observe a unique structure, a "crystal gel," that occurs when gas-liquid phase separation arrests due to crystallites within the liquid domain spanning the cell. From the initial onset of spinodal decomposition until arrest caused by this structure, the kinetics of phase separation remain largely unaffected by the formation of the third phase. This dynamic arrest appears to result from the stiffness of the crystalline strands exceeding the liquid-gas interfacial tension.
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Affiliation(s)
- Juan Sabin
- Department of Physics, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
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