1
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Qi T, Lin J, Ouyang Z. Hydrodynamic Behavior of Self-Propelled Particles in a Simple Shear Flow. ENTROPY 2022; 24:e24070854. [PMID: 35885078 PMCID: PMC9320371 DOI: 10.3390/e24070854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/20/2022] [Accepted: 06/20/2022] [Indexed: 12/04/2022]
Abstract
The hydrodynamic properties of a squirmer type of self-propelled particle in a simple shear flow are investigated using the immersed boundary-lattice Boltzmann method in the range of swimming Reynolds number 0.05 ≤ Res ≤ 2.0, flow Reynolds number 40 ≤ Rep ≤ 160, blocking rate 0.2 ≤ κ ≤ 0.5. Some results are validated by comparing with available other results. The effects of Res, Rep and κ on the hydrodynamic properties of squirmer are discussed. The results show that there exist four distinct motion modes for the squirmer, i.e., horizontal mode, attractive oscillation mode, oscillation mode, and chaotic mode. Increasing Res causes the motion mode of the squirmer to change from a constant tumbling near the centerline to a stable horizontal mode, even an oscillatory or appealing oscillatory mode near the wall. Increasing the swimming intensity of squirmer under the definite Res will induce the squirmer to make periodic and stable motion at a specific distance from the wall. Increasing Rep will cause the squirmer to change from a stable swimming state to a spiral motion or continuous rotation. Increasing κ will strengthen the wall’s attraction to the squirmer. Increasing swimming intensity of squirmer will modify the strength and direction of the wall’s attraction to the squirmer if κ remains constant.
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Affiliation(s)
- Tingting Qi
- State Key Laboratory of Fluid Power Transmission and Control, Zhejiang University, Hangzhou 310027, China; (T.Q.); (Z.O.)
| | - Jianzhong Lin
- Laboratory of Impact and Safety Engineering of Ministry of Education, Ningbo University, Ningbo 315201, China
- Correspondence: ; Tel.: +86-571-87952882
| | - Zhenyu Ouyang
- State Key Laboratory of Fluid Power Transmission and Control, Zhejiang University, Hangzhou 310027, China; (T.Q.); (Z.O.)
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2
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Friesen S, Kakorin S, Hellweg T. Modified Flory–Rehner Theory Describes Thermotropic Swelling Transition of Smart Copolymer Microgels. Polymers (Basel) 2022; 14:polym14101999. [PMID: 35631881 PMCID: PMC9143634 DOI: 10.3390/polym14101999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 05/09/2022] [Accepted: 05/10/2022] [Indexed: 12/10/2022] Open
Abstract
In the present article, we use an improved Flory–Rehner theory to describe the swelling behavior of copolymer microgels, where the interaction parameter is modeled by a Hill-like equation for a cooperative thermotropic transition. This description leads to very good fits of the swelling curves of the copolymer microgels at different comonomer contents (30 mol%, 50 mol% and 70 mol%) obtained by photon correlation spectroscopy. Fixed parameters, which are universally applicable for the respective monomers given in our previous work, are used to fit the swelling curves. The analysis of the swelling curves yields physically reasonable and meaningful results for the remaining adjustable parameters. The comonomer content of the statistical copolymer microgels poly(NNPAM-co-NIPAM), poly(NIPAM-co-NIPMAM) and poly(NIPMAM-co-NNPAM) is determined by nuclear magnetic resonance spectroscopy and is in agreement with the nominal comonomer feed used in the synthesis. To investigate the volume phase transition at a molecular level, swelling curves are also measured by Fourier transformation infrared spectroscopy. The obtained swelling curves are also fitted using the Hill-like model. The fits provide physically reasonable parameters too, consistent with the results from photon correlation spectroscopy.
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3
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Comparison of different approaches to describe the thermotropic volume phase transition of smart microgels. Colloid Polym Sci 2022. [DOI: 10.1007/s00396-022-04950-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AbstractThe description of gel swelling by Flory and Rehner using the original Flory–Huggins interaction parameter for the polymer–solvent interaction cannot be applied to most smart microgels. Here, we compare descriptions of the swelling curves of such microgels using series expansions of the Flory–Huggins parameter $$\chi$$
χ
with the results of Hill-like equation for $$\chi$$
χ
. We study N-isopropyl-acrylamide particles at different concentrations of the cross-linker N,N-methylenebisacrylamide. The hydrodynamic radius $$R_{\mathrm {H}}$$
R
H
of the microgel particles is determined using photon correlation spectroscopy. The fits with the series expansion of $$\chi$$
χ
nicely follow the experimental data. However, already with the first-order series expansion, the computed $$\Theta$$
Θ
temperatures are not physically reasonable. Moreover, the physical meaning of the parameters of the series expansion is not clear. The Hill-like equation, which we recently introduced, yields a good description of all measured microgel swelling curves and provides physically meaningful parameters. For instance, the Hill parameter $$\nu$$
ν
corresponds to the number of water molecules per network chain cooperatively leaving the chain at the volume phase transition.
Graphical abstract
Different approaches to model the Flory-Huggins interaction parameter are explored and compared with respect to the quality of the fit of microgel swelling curves.
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4
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Ponomareva E, Tadgell B, Hildebrandt M, Krüsmann M, Prévost S, Mulvaney P, Karg M. The fuzzy sphere morphology is responsible for the increase in light scattering during the shrinkage of thermoresponsive microgels. SOFT MATTER 2022; 18:807-825. [PMID: 34939641 DOI: 10.1039/d1sm01473k] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Thermoresponsive microgels undergo a volume phase transition from a swollen state under good solvent conditions to a collapsed state under poor solvent conditions. The most prominent examples of such responsive systems are based on poly-(N-isopropylacrylamide). When cross-linked with N,N'-methylenebisacrylamide, such microgels typically possess a fuzzy-spherelike morphology with a higher cross-linked core and a loosely cross-linked fuzzy shell. Despite the efforts devoted to understanding the internal structure of microgels and their kinetics during collapse/swelling, the origins of the accompanying changes in light scattering intensity have barely been addressed. In this work, we study core-shell microgels that contain small gold nanoparticle cores with microgel shells of different thicknesses and cross-linker densities. All microgels are small enough to fulfill the Rayleigh-Debye-Gans criterion at all stages of swelling. Due to the high X-ray contrast of the gold cores, we can use absolute intensity small-angle X-ray scattering to determine the number density in the dilute dispersions. This allows us to extract polymer volume fractions of the microgels at different stages of swelling from form factor analysis of small-angle neutron scattering data. We match our findings to results from temperature-dependent absorbance measurements. The increase in absorbance during the shrinkage of the microgels is related to the transition from fuzzy spheres to hard sphere-like scattering objects with a rather homogeneous density profile. We provide a first attempt to model experimental spectra using finite difference time domain simulations that take into account the structural changes during the volume phase transition. Our findings significantly contribute to the understanding of the optical properties of thermoresponsive microgels. Further, we provide polymer volume fractions and microgel refractive indices as a function of the swelling state.
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Affiliation(s)
- Ekaterina Ponomareva
- Institut für Physikalische Chemie I: Kolloide und Nanooptik, Heinrich-Heine-Universität Düsseldorf, Universitätsstrase 1, D-40225 Düsseldorf, Germany.
| | - Ben Tadgell
- ARC Centre of Excellence in Exciton Science, The University of Melbourne, School of Chemistry, Parkville, VIC 3010, Australia
| | - Marco Hildebrandt
- Institut für Physikalische Chemie I: Kolloide und Nanooptik, Heinrich-Heine-Universität Düsseldorf, Universitätsstrase 1, D-40225 Düsseldorf, Germany.
| | - Marcel Krüsmann
- Institut für Physikalische Chemie I: Kolloide und Nanooptik, Heinrich-Heine-Universität Düsseldorf, Universitätsstrase 1, D-40225 Düsseldorf, Germany.
| | - Sylvain Prévost
- Large Scale Structures, Institut Laue-Langevin, 71 avenue des Martyrs, CS 20156, 38042, Grenoble Cedex 9, France
| | - Paul Mulvaney
- ARC Centre of Excellence in Exciton Science, The University of Melbourne, School of Chemistry, Parkville, VIC 3010, Australia
| | - Matthias Karg
- Institut für Physikalische Chemie I: Kolloide und Nanooptik, Heinrich-Heine-Universität Düsseldorf, Universitätsstrase 1, D-40225 Düsseldorf, Germany.
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5
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Li Q, Peng X, Chen D, McKenna GB. Softness mapping of the concentration dependence of the dynamics in model soft colloidal systems. J Colloid Interface Sci 2021; 605:398-409. [PMID: 34332413 DOI: 10.1016/j.jcis.2021.07.089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 07/06/2021] [Accepted: 07/16/2021] [Indexed: 11/28/2022]
Abstract
The dynamics of a series of soft colloids comprised of polystyrene cores with poly(N-isopropylacrylamide) (PNIPAM) coronas was investigated by diffusing wave spectroscopy (DWS). The modulus of the coronas was varied by changing the cross-link density and we were able to interpret the results within a hard-soft mapping framework. The soft, swellable particle properties were modeled using an extended Flory-Rehner theory and a Hertzian pair potential. Following volume fraction jumps, softness effects on the concentration dependence of dynamics were determined, with a 'soft colloids make strong glass-forming liquid'-type of behavior observed close to the nominal glass transition volume fraction, φg. Such behavior from the current systems cannot be fully explained by the osmotic deswelling model alone. However, inspired by the soft-hard mapping from Schmiedeberg et al, [Europhys. Lett. 2011, 96(3), 36010] we estimated effective hard-sphere diameters and achieved a successful mapping of the α-relaxation times to a master curve below φg. Above φg, the curves no longer collapse but show strong deviations from a Vogel-Fulcher type of divergence onto soft jamming plateaux. Our results provide evidence that osmotic deswelling itself cannot fully explain the observed dynamics. Softness also plays an important role in the dynamics of soft, concentrated colloids.
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Affiliation(s)
- Qi Li
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409, United States
| | - Xiaoguang Peng
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409, United States
| | - Dongjie Chen
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409, United States
| | - Gregory B McKenna
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409, United States.
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6
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Scotti A, Denton AR, Brugnoni M, Schweins R, Richtering W. Absence of crystals in the phase behavior of hollow microgels. Phys Rev E 2021; 103:022612. [PMID: 33736081 DOI: 10.1103/physreve.103.022612] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 01/29/2021] [Indexed: 05/20/2023]
Abstract
Solutions of microgels have been widely used as model systems to gain insight into atomic condensed matter and complex fluids. We explore the thermodynamic phase behavior of hollow microgels, which are distinguished from conventional colloids by a central cavity. Small-angle neutron and x-ray scattering are used to probe hollow microgels in crowded environments. These measurements reveal an interplay among deswelling, interpenetration, and faceting and an unusual absence of crystals. Monte Carlo simulations of model systems confirm that, due to the cavity, solutions of hollow microgels more readily form a supercooled liquid than for microgels with a cross-linked core.
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Affiliation(s)
- A Scotti
- Institute of Physical Chemistry, RWTH Aachen University, 52056 Aachen, Germany
| | - A R Denton
- Department of Physics, North Dakota State University, Fargo, North Dakota 58108-6050 USA
| | - M Brugnoni
- Institute of Physical Chemistry, RWTH Aachen University, 52056 Aachen, Germany
| | - R Schweins
- Institut Laue-Langevin ILL DS/LSS, 71 Avenue des Martyrs, F-38000 Grenoble, France
| | - W Richtering
- Institute of Physical Chemistry, RWTH Aachen University, 52056 Aachen, Germany
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7
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Scheffold F. Pathways and challenges towards a complete characterization of microgels. Nat Commun 2020; 11:4315. [PMID: 32887886 PMCID: PMC7473851 DOI: 10.1038/s41467-020-17774-5] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Accepted: 07/20/2020] [Indexed: 01/07/2023] Open
Abstract
Due to their controlled size, sensitivity to external stimuli, and ease-of-use, microgel colloids are unique building blocks for soft materials made by crosslinking polymers on the micrometer scale. Despite the plethora of work published, many questions about their internal structure, interactions, and phase behavior are still open. The reasons for this lack of understanding are the challenges arising from the small size of the microgel particles, complex pairwise interactions, and their solvent permeability. Here we describe pathways toward a complete understanding of microgel colloids based on recent experimental advances in nanoscale characterization, such as super-resolution microscopy, scattering methods, and modeling.
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Affiliation(s)
- Frank Scheffold
- Department of Physics, University of Fribourg, Chemin du Musée 3, 1700, Fribourg, Switzerland.
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8
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Hollfelder CO, Jende LN, Dietrich H, Eichele K, Maichle‐Mössmer C, Anwander R. 1,3‐Diene Polymerization Promoted by Half‐Sandwich Rare‐Earth‐Metal Dimethyl Complexes: Active Species Clustering and Cationization/Deactivation Processes. Chemistry 2019; 25:7298-7302. [PMID: 30945775 DOI: 10.1002/chem.201901269] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Indexed: 11/08/2022]
Affiliation(s)
- Christoph O. Hollfelder
- Institut für Anorganische Chemie, Eberhard-Karls-Universität Tübingen Auf der Morgenstelle 18 72076 Tübingen Germany
| | - Lars N. Jende
- Institut für Anorganische Chemie, Eberhard-Karls-Universität Tübingen Auf der Morgenstelle 18 72076 Tübingen Germany
| | - Hans‐Martin Dietrich
- Institut für Anorganische Chemie, Eberhard-Karls-Universität Tübingen Auf der Morgenstelle 18 72076 Tübingen Germany
| | - Klaus Eichele
- Institut für Anorganische Chemie, Eberhard-Karls-Universität Tübingen Auf der Morgenstelle 18 72076 Tübingen Germany
| | - Cäcilia Maichle‐Mössmer
- Institut für Anorganische Chemie, Eberhard-Karls-Universität Tübingen Auf der Morgenstelle 18 72076 Tübingen Germany
| | - Reiner Anwander
- Institut für Anorganische Chemie, Eberhard-Karls-Universität Tübingen Auf der Morgenstelle 18 72076 Tübingen Germany
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9
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Leite DC, Kakorin S, Hertle Y, Hellweg T, da Silveira NP. Smart Starch-Poly( N-isopropylacrylamide) Hybrid Microgels: Synthesis, Structure, and Swelling Behavior. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:10943-10954. [PMID: 30132672 DOI: 10.1021/acs.langmuir.8b00706] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In this study, we present hybrid microgels made of starch nanoparticles (SNPs) and poly( N-isopropylacrylamide) [p(NIPAM)]. SNPs were formed through nanoprecipitation. Hybrid microgels were prepared by surfactant-free precipitation polymerization (SFPP) or in the presence of surfactant precipitation polymerization (PP) at different NIPAM/SNP ratios. Dynamic light scattering results of hybrid microgels synthesized by SFPP revealed changes in volume phase transition temperature according to SNP amount, where the increase in the hydrophilic content caused small shifts in the lower critical solution temperature (LCST), reaching nearly 35 °C. Colloidal stability was improved with the SNP content, leading to increased stability because of the hydroxyl groups. Small-angle X-ray scattering indicates a core-shell structure above the LCST, where SNPs chains cover a p(NIPAM) core. Swelling curves experimentally obtained were analyzed using the Flory-Rehner model, where the interaction parameter (χ) has been modeled either by a series expansion of the swelling ratio or by a Hill-like equation for a cooperative thermotropic transition.
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Affiliation(s)
- Daiani C Leite
- Institute of Chemistry , Universidade Federal do Rio Grande do Sul , Av. Bento Gonçalves 9500 , 91501-970 Porto Alegre , Brazil
| | - Sergej Kakorin
- Faculty of Chemistry , Universität Bielefeld , Universitätstrasse 25 , 33615 Bielefeld , Germany
| | - Yvonne Hertle
- Faculty of Chemistry , Universität Bielefeld , Universitätstrasse 25 , 33615 Bielefeld , Germany
| | - Thomas Hellweg
- Faculty of Chemistry , Universität Bielefeld , Universitätstrasse 25 , 33615 Bielefeld , Germany
| | - Nádya P da Silveira
- Institute of Chemistry , Universidade Federal do Rio Grande do Sul , Av. Bento Gonçalves 9500 , 91501-970 Porto Alegre , Brazil
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10
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Nigro V, Angelini R, Bertoldo M, Ruzicka B. Swelling of responsive-microgels: experiments versus models. Colloids Surf A Physicochem Eng Asp 2017. [DOI: 10.1016/j.colsurfa.2017.04.059] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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11
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Meng G, Manoharan VN, Perro A. Core-shell colloidal particles with dynamically tunable scattering properties. SOFT MATTER 2017; 13:6293-6296. [PMID: 28900641 DOI: 10.1039/c7sm01740e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We design polystyrene-poly(N'-isopropylacrylamide-co-acrylic acid) core-shell particles that exhibit dynamically tunable scattering. We show that under normal solvent conditions the shell is nearly index-matched to pure water, and the particle scattering is dominated by Rayleigh scattering from the core. As the temperature or salt concentration increases, both the scattering cross-section and the forward scattering increase, characteristic of Mie scatterers. The magnitude of the change in the scattering cross-section and scattering anisotropy can be controlled through the solvent conditions and the size of the core. Such particles may find use as optical switches or optical filters with tunable opacity.
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Affiliation(s)
- Guangnan Meng
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
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12
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Seyboldt R, Merger D, Coupette F, Siebenbürger M, Ballauff M, Wilhelm M, Fuchs M. Divergence of the third harmonic stress response to oscillatory strain approaching the glass transition. SOFT MATTER 2016; 12:8825-8832. [PMID: 27752694 DOI: 10.1039/c6sm01616b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The leading nonlinear stress response in a periodically strained concentrated colloidal dispersion is studied experimentally and by theory. A thermosensitive microgel dispersion serves as well-characterized glass-forming model, where the stress response at the first higher harmonic frequency (3ω for strain at frequency ω) is investigated in the limit of small amplitude. The intrinsic nonlinearity at the third harmonic exhibits a scaling behavior which has a maximum in an intermediate frequency window and diverges when approaching the glass transition. It captures the (in-) stability of the transient elastic structure. Elastic stresses in-phase with the third power of the strain dominate the scaling. Our results qualitatively differ from previously derived scaling behavior in dielectric spectroscopy of supercooled molecular liquids. This might indicate a dependence of the nonlinear response on the symmetry of the external driving under time reversal.
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Affiliation(s)
- Rabea Seyboldt
- Department of Physics, Universität Konstanz, 78464 Konstanz, Germany. and Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany
| | - Dimitri Merger
- Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
| | - Fabian Coupette
- Department of Physics, Universität Konstanz, 78464 Konstanz, Germany.
| | - Miriam Siebenbürger
- Institute Soft Matter and Functional Materials, Helmholtz-Zentrum Berlin, 14109 Berlin, Germany
| | - Matthias Ballauff
- Institute Soft Matter and Functional Materials, Helmholtz-Zentrum Berlin, 14109 Berlin, Germany
| | - Manfred Wilhelm
- Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
| | - Matthias Fuchs
- Department of Physics, Universität Konstanz, 78464 Konstanz, Germany.
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13
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Kureha T, Shibamoto T, Matsui S, Sato T, Suzuki D. Investigation of Changes in the Microscopic Structure of Anionic Poly(N-isopropylacrylamide-co-Acrylic acid) Microgels in the Presence of Cationic Organic Dyes toward Precisely Controlled Uptake/Release of Low-Molecular-Weight Chemical Compound. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:4575-85. [PMID: 27101468 DOI: 10.1021/acs.langmuir.6b00760] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Changes in a microscopic structure of an anionic poly(N-isopropylacrylamide-co-acrylic acid) microgel were investigated using small- and wide-angle X-ray scattering (SWAXS). The scattering profiles of the microgels were analyzed in a wide scattering vector (q) range of 0.07 ≤ q/nm(-1) ≤ 20. In particular, the microscopic structure of the microgel in the presence of a cationic dye rhodamine 6G (R6G) was characterized in terms of its correlation length (ξ), which represents the length scale of the spatial correlation of the network density fluctuations, and characteristic distance (d*), which originated from the local packing of isopropyl groups of two neighboring chains. In the presence of cationic R6G, ξ exhibited a divergent-like behavior, which was not seen in the absence of R6G, and d* was decreased with decreasing the volume of the microgel upon increasing temperature. At the same time, the amount of R6G adsorbed per unit mass of the microgel increased upon heating. These results suggested that a coil-to-globule transition of the poly(N-isopropylacrylamide) chains in the present anionic microgel occurred because of efficiently screened, thus, short ranged electrostatic repulsion between the charged groups, and hydrophobic interaction between the isopropyl groups in the presence of cationic R6G. The combination of hydrophobic and electrostatic interaction between the cationic dye and the microgel affected the separation and volume transition behavior of the microgel.
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Affiliation(s)
- Takuma Kureha
- Graduate School of Textile Science & Technology, Shinshu University , 3-15-1 Tokida Ueda, Nagano 386-8567 Japan
| | - Takahisa Shibamoto
- Graduate School of Textile Science & Technology, Shinshu University , 3-15-1 Tokida Ueda, Nagano 386-8567 Japan
| | - Shusuke Matsui
- Graduate School of Textile Science & Technology, Shinshu University , 3-15-1 Tokida Ueda, Nagano 386-8567 Japan
| | - Takaaki Sato
- Graduate School of Textile Science & Technology, Shinshu University , 3-15-1 Tokida Ueda, Nagano 386-8567 Japan
| | - Daisuke Suzuki
- Graduate School of Textile Science & Technology, Shinshu University , 3-15-1 Tokida Ueda, Nagano 386-8567 Japan
- Division of Smart Textiles, Institute for Fiber Engineering, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University , 3-15-1 Tokida, Ueda, Nagano 386-8567, Japan
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14
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15
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Suzuki D, Shibata K, Tsuchida A, Okubo T. Thermo-sensitive colloidal crystals composed of monodisperse colloidal silica- and poly(N-isopropyl acrylamide) gel spheres. Colloid Polym Sci 2015. [DOI: 10.1007/s00396-015-3661-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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16
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Amann CM, Siebenbürger M, Ballauff M, Fuchs M. Nonlinear rheology of glass-forming colloidal dispersions: transient stress-strain relations from anisotropic mode coupling theory and thermosensitive microgels. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:194121. [PMID: 25922898 DOI: 10.1088/0953-8984/27/19/194121] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Transient stress-strain relations close to the colloidal glass transition are obtained within the integration through transients framework generalizing mode coupling theory to flow driven systems. Results from large-scale numerical calculations are quantitatively compared to experiments on thermosensitive microgels, which reveals that theory captures the magnitudes of stresses semi-quantitatively even in the nonlinear regime, but overestimates the characteristic strain where plastic events set in. The former conclusion can also be drawn from flow curves, while the latter conclusion is supported by a comparison to single particle motion measured by confocal microscopy. The qualitative picture, as previously obtained from simplifications of the theory in schematic models, is recovered by the quantitative solutions of the theory for Brownian hard spheres.
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Affiliation(s)
- C M Amann
- Fachbereich Physik, Universität Konstanz, 78457 Konstanz, Germany
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17
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Suzue A, Honda H, Kadokura M, Tanaka S, Tukada H. Investigation of New Cooling Systems Based on Complexes of Temperature-Responsive Poly(N-isopropylacrylamide) with Porous Materials. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2014. [DOI: 10.1246/bcsj.20140187] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Atsushi Suzue
- Graduate School of Nanobioscience, Yokohama City University
| | - Hisashi Honda
- Graduate School of Nanobioscience, Yokohama City University
| | - Meiko Kadokura
- International College of Arts and Sciences, Yokohama City University
| | - Susumu Tanaka
- Department of Materials Science, Yonago National College of Technology
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18
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Palberg T. Crystallization kinetics of colloidal model suspensions: recent achievements and new perspectives. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:333101. [PMID: 25035303 DOI: 10.1088/0953-8984/26/33/333101] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Colloidal model systems allow studying crystallization kinetics under fairly ideal conditions, with rather well-characterized pair interactions and minimized external influences. In complementary approaches experiment, analytic theory and simulation have been employed to study colloidal solidification in great detail. These studies were based on advanced optical methods, careful system characterization and sophisticated numerical methods. Over the last decade, both the effects of the type, strength and range of the pair-interaction between the colloidal particles and those of the colloid-specific polydispersity have been addressed in a quantitative way. Key parameters of crystallization have been derived and compared to those of metal systems. These systematic investigations significantly contributed to an enhanced understanding of the crystallization processes in general. Further, new fundamental questions have arisen and (partially) been solved over the last decade: including, for example, a two-step nucleation mechanism in homogeneous nucleation, choice of the crystallization pathway, or the subtle interplay of boundary conditions in heterogeneous nucleation. On the other hand, via the application of both gradients and external fields the competition between different nucleation and growth modes can be controlled and the resulting microstructure be influenced. The present review attempts to cover the interesting developments that have occurred since the turn of the millennium and to identify important novel trends, with particular focus on experimental aspects.
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Affiliation(s)
- Thomas Palberg
- Institut für Physik, Johannes Gutenberg Universität Mainz, 55099 Mainz, Germany
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19
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Conformational, optical, electro-optical, and dynamic characteristics of cross-linked poly(N-acryloyl-11-aminoundecanoic acid). Colloid Polym Sci 2014. [DOI: 10.1007/s00396-014-3346-1] [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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20
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Cationic gel crystals and amorphous solids of lightly cross-linked poly(2-vinylpyridine) spheres in the deionized aqueous suspension. Colloid Polym Sci 2014. [DOI: 10.1007/s00396-014-3228-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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21
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Di X, Peng X, McKenna GB. Dynamics of a thermo-responsive microgel colloid near to the glass transition. J Chem Phys 2014; 140:054903. [DOI: 10.1063/1.4863327] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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22
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Messlinger S, Kramer C, Schmied JJ, Winkel F, Schöpf W, Rehberg I. Experimental observations of Soret-driven convection in the transient diffusive boundary layer. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 88:053019. [PMID: 24329363 DOI: 10.1103/physreve.88.053019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2013] [Indexed: 06/03/2023]
Abstract
The onset of transient Soret-driven convection is investigated experimentally in a colloidal suspension of thermosensitive nanoparticles by the shadowgraph technique and by particle tracking observations. From the shadowgraph images, the concentration profile is reconstructed, giving evidence of a convective motion inside the transient boundary layer. Furthermore, the latency times for the convection onset are extracted from the measurements. The results point out that particle tracking is superior to the shadowgraph method for detecting the onset of convection. The onset latency times obtained from these experiments obey scaling laws which are in accordance with the predictions from theoretical treatments.
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Affiliation(s)
| | - Christoph Kramer
- Experimentalphysik V, Universität Bayreuth, 95440 Bayreuth, Germany
| | - Jürgen J Schmied
- Experimentalphysik V, Universität Bayreuth, 95440 Bayreuth, Germany
| | - Florian Winkel
- Experimentalphysik V, Universität Bayreuth, 95440 Bayreuth, Germany
| | - Wolfgang Schöpf
- Experimentalphysik V, Universität Bayreuth, 95440 Bayreuth, Germany
| | - Ingo Rehberg
- Experimentalphysik V, Universität Bayreuth, 95440 Bayreuth, Germany
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23
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Rigidity of the crystals of thermo-sensitive gel spheres of poly (N-isopropyl acrylamide) in the deionized aqueous media as studied by the reflection spectroscopy in the sedimentation equilibrium. Colloid Polym Sci 2013. [DOI: 10.1007/s00396-013-2907-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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24
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Cationic gel crystals of lightly cross-linked poly(2-vinylpyridine) spheres (170∼180 nm in diameter) in the deionized aqueous suspension. Colloid Polym Sci 2013. [DOI: 10.1007/s00396-013-3000-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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25
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26
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Affiliation(s)
- H. Henning Winter
- Department
of Chemical Engineering and Department of
Polymer Science and Engineering, University of Massachusetts, Amherst, Massachusetts 01003, United States
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27
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Okubo T, Fujii S, Aono K, Nakamura Y, Tsuchida A. Colloidal crystallization of cationic gel spheres of lightly cross-linked poly(2-vinylpyridine) in the deionized aqueous suspension. Colloid Polym Sci 2012. [DOI: 10.1007/s00396-012-2850-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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28
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Crystal structure of thermosensitive gel spheres of poly(N-isopropylacrylamide) in the deionized aqueous suspension as studied by the static light-scattering measurements. Colloid Polym Sci 2012. [DOI: 10.1007/s00396-012-2770-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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29
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Wedel B, Zeiser M, Hellweg T. Non NIPAM Based Smart Microgels: Systematic Variation of the Volume Phase Transition Temperature by Copolymerization. ACTA ACUST UNITED AC 2012. [DOI: 10.1524/zpch.2012.0267] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Thermoresponsive copolymer microgels based on N-n-propylacrylamide (NNPAM) and N-isopropylmethacrylamide (NIPMAM) with varying compositions were synthesized via precipitation polymerization. Photon correlation spectroscopy (PCS) and turbidity measurements were used to investigate their volume phase transition. A linear correlation between the nominal composition and the volume phase transition temperature (VPTT) was observed. Furthermore, the hydrodynamic radii of the particles exhibit a linear dependency on the nominal composition. The presented system is suitable for the synthesis of thermoresponsive microgels with a well defined VPTT or size and gives access to tune these two crucial parameters in a systematic and controlled way by simply choosing the right composition of the monomer feed. Additionally, the first derivatives of the swelling curves obtained from turbidity measurements were analyzed in detail, allowing a quantitative comparison of the phase transition of different microgels.
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30
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Hunter GL, Weeks ER. The physics of the colloidal glass transition. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2012; 75:066501. [PMID: 22790649 DOI: 10.1088/0034-4885/75/6/066501] [Citation(s) in RCA: 334] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
As one increases the concentration of a colloidal suspension, the system exhibits a dramatic increase in viscosity. Beyond a certain concentration, the system is said to be a colloidal glass; structurally, the system resembles a liquid, yet motions within the suspension are slow enough that it can be considered essentially frozen. For several decades, colloids have served as a valuable model system for understanding the glass transition in molecular systems. The spatial and temporal scales involved allow these systems to be studied by a wide variety of experimental techniques. The focus of this review is the current state of understanding of the colloidal glass transition, with an emphasis on experimental observations. A brief introduction is given to important experimental techniques used to study the glass transition in colloids. We describe features of colloidal systems near and in glassy states, including increases in viscosity and relaxation times, dynamical heterogeneity and ageing, among others. We also compare and contrast the glass transition in colloids to that in molecular liquids. Other glassy systems are briefly discussed, as well as recently developed synthesis techniques that will keep these systems rich with interesting physics for years to come.
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Affiliation(s)
- Gary L Hunter
- Department of Physics, Emory University, Math and Science Center 400 Dowman Dr., N201 Atlanta, GA 30322, USA
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31
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Okubo T, Suzuki D, Shibata K, Tsuchida A. Kinetic studies of colloidal crystallization of thermo-sensitive gel spheres of poly(N-isopropylacrylamide). Colloid Polym Sci 2012. [DOI: 10.1007/s00396-012-2666-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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32
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Suzuki D, Yamagata T, Horigome K, Shibata K, Tsuchida A, Okubo T. Colloidal crystallization of thermo-sensitive gel spheres of poly (N-isopropyl acrylamide). Influence of gel size. Colloid Polym Sci 2011. [DOI: 10.1007/s00396-011-2534-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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33
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Zaccone A, Crassous JJ, Béri B, Ballauff M. Quantifying the reversible association of thermosensitive nanoparticles. PHYSICAL REVIEW LETTERS 2011; 107:168303. [PMID: 22107434 DOI: 10.1103/physrevlett.107.168303] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Indexed: 05/21/2023]
Abstract
Under many conditions, biomolecules and nanoparticles associate by means of attractive bonds, due to hydrophobic attraction. Extracting the microscopic association or dissociation rates from experimental data is complicated by the dissociation events and by the sensitivity of the binding force to temperature (T). Here we introduce a theoretical model that combined with light-scattering experiments allows us to quantify these rates and the reversible binding energy as a function of T. We apply this method to the reversible aggregation of thermoresponsive polystyrene/poly(N-isopropylacrylamide) core-shell nanoparticles, as a model system for biomolecules. We find that the binding energy changes sharply with T, and relate this remarkable switchable behavior to the hydrophobic-hydrophilic transition of the thermosensitive nanoparticles.
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Affiliation(s)
- Alessio Zaccone
- Department of Physics, Cavendish Laboratory, University of Cambridge, Cambridge, United Kingdom
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34
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Colloidal crystallization of thermo-sensitive gel spheres of poly (N-isopropyl acrylamide). Influence of degree of cross-linking of the gels. Colloid Polym Sci 2011. [DOI: 10.1007/s00396-011-2499-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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35
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Okubo T, Suzuki D, Yamagata T, Horigome K, Shibata K, Tsuchida A. Colloidal crystallization of thermosensitive gel spheres of poly(N-isopropylacrylamide) with low degree of cross-linking. Colloid Polym Sci 2011. [DOI: 10.1007/s00396-011-2459-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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36
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Lu Y, Ballauff M. Thermosensitive core–shell microgels: From colloidal model systems to nanoreactors. Prog Polym Sci 2011. [DOI: 10.1016/j.progpolymsci.2010.12.003] [Citation(s) in RCA: 209] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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37
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Hamcerencu M, Desbrieres J, Khoukh A, Popa M, Riess G. Thermodynamic investigation of thermoresponsive xanthan-poly (N
-isopropylacrylamide) hydrogels. POLYM INT 2011. [DOI: 10.1002/pi.3113] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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38
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Colloidal crystallization of thermo-sensitive gel spheres of poly (N-isopropyl acrylamide). Colloid Polym Sci 2010. [DOI: 10.1007/s00396-010-2358-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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39
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Responsive P(NIPAM-co-NtBAM) microgels: Flory–Rehner description of the swelling behaviour. Colloid Polym Sci 2010. [DOI: 10.1007/s00396-010-2232-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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40
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Pich A, Richtering W. Microgels by Precipitation Polymerization: Synthesis, Characterization, and Functionalization. CHEMICAL DESIGN OF RESPONSIVE MICROGELS 2010. [DOI: 10.1007/12_2010_70] [Citation(s) in RCA: 130] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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41
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Lu Y, Drechsler M. Charge-induced self-assembly of 2-dimensional thermosensitive microgel particle patterns. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:13100-13105. [PMID: 19839569 DOI: 10.1021/la903418m] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The self-assembly of charged microgel particles into two-dimensional arrays on various substrates have been investigated by depositing the diluted microgel dispersion on the substrate and drying at room temperature. Core-shell type thermosensitive microgel particles consist of poly(styrene) (PS) core, whereas the shell consists of poly(N-isopropylacrylamide) (PNIPA) network cross-linked by N,N'-methylenebisacrylamide (BIS). It is found that the electrostatic interactions between microgel particles and charged substrate surface play an important role for the formation of ordered 2-D pattern. When microgel particles are deposited onto the substrate with opposite surface charges, microgels will form ordered 2-D arrays with constant distance between particles. When substrate with same surface charge as microgel particles was used, the electrostatic repulsion between microgel particles and substrate will destroy the ordered structure. Moreover, after embedding Au nanoparticles into the thermosensitive microgel particles, the microgel-Au composite particles can also assemble into 2-D arrays on the substrate.
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Affiliation(s)
- Yan Lu
- Physikalische Chemie I, University of Bayreuth, 95440 Bayreuth, Germany.
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42
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Preparation and characterization of poly (N-isopropylacrylamide)/polyvinylamine core-shell microgels. Colloid Polym Sci 2009. [DOI: 10.1007/s00396-009-2095-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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43
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Bolisetty S, Schneider C, Polzer F, Ballauff M, Li W, Zhang A, Schlüter AD. Formation of Stable Mesoglobules by a Thermosensitive Dendronized Polymer. Macromolecules 2009. [DOI: 10.1021/ma901135a] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | | | - Matthias Ballauff
- Present address: Soft Matter and Functional Materials, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Glienicker Strasse 100, 14109 Berlin, Germany, and Department of Physics, Humboldt University Berlin, Newtonstr. 15, 12489 Berlin, Germany
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44
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Crassous JJ, Rochette CN, Wittemann A, Schrinner M, Ballauff M, Drechsler M. Quantitative analysis of polymer colloids by cryo-transmission electron microscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:7862-7871. [PMID: 19317419 DOI: 10.1021/la900442x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The structure of colloidal latex particles in dilute suspension at room temperature is investigated by cryogenic transmission electron microscopy (cryo-TEM). Two types of particles are analyzed: (i) core particles made of polystyrene with a thin layer of poly(N-isopropylacrylamide) (PNIPAM) and (ii) core-shell particles consisting of core particles onto which a network of cross-linked PNIPAM is affixed. Both systems are also studied by small-angle X-ray scattering (SAXS). The radial density profile of both types of particles have been derived from the cryo-TEM micrographs by image processing and compared to the results obtained by SAXS. Full agreement is found for the core particles. There is a discrepancy between the two methods in case of the core-shell particles. The discrepancy is due to the buckling of the network affixed to the surface. The buckling is clearly visible in the cryo-TEM pictures. The overall dimensions derived from cryo-TEM agree well with the hydrodynamic radius of the particles. The comparison of these data with the analysis by SAXS shows that SAXS is only sensitive to the average radial structure as expected. All data show that cryo-TEM micrographs can be evaluated to yield quantitative information about the structure of colloidal particles.
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Affiliation(s)
- J J Crassous
- Physikalische Chemie I, University of Bayreuth, 95440 Bayreuth, Germany
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45
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Chi C, Cai T, Hu Z. Oligo(ethylene glycol)-based thermoresponsive core-shell microgels. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:3814-3819. [PMID: 19708256 DOI: 10.1021/la803866z] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Oligo(ethylene glycol)-based thermoresponsive core-shell microgels were synthesized by a two-step polymerization method: The core particles mainly consisted of poly(ethylene glycol) ethyl ether methacrylate (PEGEEMA), while the shell mainly consisted of a copolymer of PEGEEMA, poly(ethylene glycol) methyl ether methacrylate (PEGMEMA), and poly(acrylic acid). The copolymerization of the shell resulted in a higher volume phase transition temperature than that of the core. The mass of a single microgel particle was determined by both the static light scattering method and a new method using UV-visible spectroscopy. Core-shell microgels in water self-assembled into crystalline structures with iridescent colors, which were the result of Bragg diffraction. The melting kinetics of microgel crystals was studied by using UV-visible transmission spectroscopy.
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Affiliation(s)
- Chenglin Chi
- Department of Physics, University of North Texas, Denton, Texas 76203, USA
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46
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Bolisetty S, Hoffmann M, Lekkala S, Hellweg T, Ballauff M, Harnau L. Coupling of Rotational Motion with Shape Fluctuations of Core−Shell Microgels Having Tunable Softness. Macromolecules 2009. [DOI: 10.1021/ma8022603] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- S. Bolisetty
- Physikalische Chemie I, University of Bayreuth, D-95440 Bayreuth, Germany, and Max-Planck-Institut für Metallforschung, Heisenbergstr. 3, D-70569 Stuttgart, Germany, and Institut für Theoretische and Angewandte Physik, Universität Stuttgart, Pfaffenwaldring 57, D-70569 Stuttgart, Germany
| | - M. Hoffmann
- Physikalische Chemie I, University of Bayreuth, D-95440 Bayreuth, Germany, and Max-Planck-Institut für Metallforschung, Heisenbergstr. 3, D-70569 Stuttgart, Germany, and Institut für Theoretische and Angewandte Physik, Universität Stuttgart, Pfaffenwaldring 57, D-70569 Stuttgart, Germany
| | - S. Lekkala
- Physikalische Chemie I, University of Bayreuth, D-95440 Bayreuth, Germany, and Max-Planck-Institut für Metallforschung, Heisenbergstr. 3, D-70569 Stuttgart, Germany, and Institut für Theoretische and Angewandte Physik, Universität Stuttgart, Pfaffenwaldring 57, D-70569 Stuttgart, Germany
| | - Th. Hellweg
- Physikalische Chemie I, University of Bayreuth, D-95440 Bayreuth, Germany, and Max-Planck-Institut für Metallforschung, Heisenbergstr. 3, D-70569 Stuttgart, Germany, and Institut für Theoretische and Angewandte Physik, Universität Stuttgart, Pfaffenwaldring 57, D-70569 Stuttgart, Germany
| | - M. Ballauff
- Physikalische Chemie I, University of Bayreuth, D-95440 Bayreuth, Germany, and Max-Planck-Institut für Metallforschung, Heisenbergstr. 3, D-70569 Stuttgart, Germany, and Institut für Theoretische and Angewandte Physik, Universität Stuttgart, Pfaffenwaldring 57, D-70569 Stuttgart, Germany
| | - L. Harnau
- Physikalische Chemie I, University of Bayreuth, D-95440 Bayreuth, Germany, and Max-Planck-Institut für Metallforschung, Heisenbergstr. 3, D-70569 Stuttgart, Germany, and Institut für Theoretische and Angewandte Physik, Universität Stuttgart, Pfaffenwaldring 57, D-70569 Stuttgart, Germany
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47
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Eckert T, Richtering W. Publisher’s Note: “Thermodynamic and hydrodynamic interaction in concentrated microgel suspensions: Hard or soft sphere behavior?” [J. Chem. Phys. 129, 124902 (2008)]. J Chem Phys 2009. [DOI: 10.1063/1.3068640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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48
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Mohanty PS, Richtering W. Structural Ordering and Phase Behavior of Charged Microgels. J Phys Chem B 2008; 112:14692-7. [DOI: 10.1021/jp808203d] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- P. S. Mohanty
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany
| | - W. Richtering
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany
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49
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Eckert T, Richtering W. Thermodynamic and hydrodynamic interaction in concentrated microgel suspensions: Hard or soft sphere behavior? J Chem Phys 2008; 129:124902. [DOI: 10.1063/1.2978383] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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50
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Crassous JJ, Siebenbürger M, Ballauff M, Drechsler M, Hajnal D, Henrich O, Fuchs M. Shear stresses of colloidal dispersions at the glass transition in equilibrium and in flow. J Chem Phys 2008; 128:204902. [PMID: 18513043 DOI: 10.1063/1.2921801] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We consider a model dense colloidal dispersion at the glass transition, and investigate the connection between equilibrium stress fluctuations, seen in linear shear moduli, and the shear stresses under strong flow conditions far from equilibrium, viz., flow curves for finite shear rates. To this purpose, thermosensitive core-shell particles consisting of a polystyrene core and a cross-linked poly(N-isopropylacrylamide) shell were synthesized. Data over an extended range in shear rates and frequencies are compared to theoretical results from integrations through transients and mode coupling approaches. The connection between nonlinear rheology and glass transition is clarified. While the theoretical models semiquantitatively fit the data taken in fluid states and the predominant elastic response of glass, a yet unaccounted dissipative mechanism is identified in glassy states.
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Affiliation(s)
- J J Crassous
- Physikalische Chemie I, University of Bayreuth, 95440 Bayreuth, Germany
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