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Blovský T, Šindelka K, Limpouchová Z, Procházka K. Self-Assembly of Symmetric Copolymers in Slits with Inert and Attractive Walls. Polymers (Basel) 2023; 15:4458. [PMID: 38006182 PMCID: PMC10675682 DOI: 10.3390/polym15224458] [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: 09/25/2023] [Revised: 11/01/2023] [Accepted: 11/14/2023] [Indexed: 11/26/2023] Open
Abstract
Although the behavior of the confined semi-dilute solutions of self-assembling copolymers represents an important topic of basic and applied research, it has eluded the interest of scientists. Extensive series of dissipative particle dynamics simulations have been performed on semi-dilute solutions of A5B5 chains in a selective solvent for A in slits using a DL-MESO simulation package. Simulations of corresponding bulk systems were performed for comparison. This study shows that the associates in the semi-dilute bulk solutions are partly structurally organized. Mild steric constraints in slits with non-attractive walls hardly affect the size of the associates, but they promote their structural arrangement in layers parallel to the slit walls. Attractive walls noticeably affect the association process. In slits with mildly attractive walls, the adsorption competes with the association process. At elevated concentrations, the associates start to form in wide slits when the walls are sparsely covered by separated associates, and the association process prevents the full coverage of the surface. In slits with strongly attractive walls, adsorption is the dominant behavior. The associates form in wide slits at elevated concentrations only after the walls are completely and continuously covered by the adsorbed chains.
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Affiliation(s)
- Tomáš Blovský
- The Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 128 40 Prague, Czech Republic;
| | - Karel Šindelka
- Department of Molecular and Mesoscopic Modelling, Institute of Chemical Process Fundamentals, Czech Academy of Sciences, Rozvojová 135, 165 02 Prague, Czech Republic;
| | - Zuzana Limpouchová
- The Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 128 40 Prague, Czech Republic;
| | - Karel Procházka
- The Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 128 40 Prague, Czech Republic;
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Procházka K, Limpouchová Z, Štěpánek M, Šindelka K, Lísal M. DPD Modelling of the Self- and Co-Assembly of Polymers and Polyelectrolytes in Aqueous Media: Impact on Polymer Science. Polymers (Basel) 2022; 14:polym14030404. [PMID: 35160394 PMCID: PMC8838752 DOI: 10.3390/polym14030404] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/17/2022] [Accepted: 01/18/2022] [Indexed: 02/04/2023] Open
Abstract
This review article is addressed to a broad community of polymer scientists. We outline and analyse the fundamentals of the dissipative particle dynamics (DPD) simulation method from the point of view of polymer physics and review the articles on polymer systems published in approximately the last two decades, focusing on their impact on macromolecular science. Special attention is devoted to polymer and polyelectrolyte self- and co-assembly and self-organisation and to the problems connected with the implementation of explicit electrostatics in DPD numerical machinery. Critical analysis of the results of a number of successful DPD studies of complex polymer systems published recently documents the importance and suitability of this coarse-grained method for studying polymer systems.
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Affiliation(s)
- Karel Procházka
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Prague, Czech Republic; (Z.L.); (M.Š.)
- Correspondence:
| | - Zuzana Limpouchová
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Prague, Czech Republic; (Z.L.); (M.Š.)
| | - Miroslav Štěpánek
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Prague, Czech Republic; (Z.L.); (M.Š.)
| | - Karel Šindelka
- Department of Molecular and Mesoscopic Modelling, Institute of Chemical Process Fundamentals, Czech Academy of Sciences, Rozvojová 135, 165 02 Prague, Czech Republic; (K.Š.); (M.L.)
| | - Martin Lísal
- Department of Molecular and Mesoscopic Modelling, Institute of Chemical Process Fundamentals, Czech Academy of Sciences, Rozvojová 135, 165 02 Prague, Czech Republic; (K.Š.); (M.L.)
- Department of Physics, Faculty of Science, Jan Evangelista Purkyně University in Ústí nad Labem, Pasteurova 3632, 400 96 Ústí n. Labem, Czech Republic
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Šindelka K, Limpouchová Z, Procházka K. Solubilization of Charged Porphyrins in Interpolyelectrolyte Complexes: A Computer Study. Polymers (Basel) 2021; 13:502. [PMID: 33562022 PMCID: PMC7915837 DOI: 10.3390/polym13040502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 01/29/2021] [Accepted: 02/03/2021] [Indexed: 11/21/2022] Open
Abstract
Using coarse-grained dissipative particle dynamics (DPD) with explicit electrostatics, we performed (i) an extensive series of simulations of the electrostatic co-assembly of asymmetric oppositely charged copolymers composed of one (either positively or negatively charged) polyelectrolyte (PE) block A and one water-soluble block B and (ii) studied the solubilization of positively charged porphyrin derivatives (P+) in the interpolyelectrolyte complex (IPEC) cores of co-assembled nanoparticles. We studied the stoichiometric mixtures of 137 A10+B25 and 137 A10-B25 chains with moderately hydrophobic A blocks (DPD interaction parameter aAS=35) and hydrophilic B blocks (aBS=25) with 10 to 120 P+ added (aPS=39). The P+ interactions with other components were set to match literature information on their limited solubility and aggregation behavior. The study shows that the moderately soluble P+ molecules easily solubilize in IPEC cores, where they partly replace PE+ and electrostatically crosslink PE- blocks. As the large P+ rings are apt to aggregate, P+ molecules aggregate in IPEC cores. The aggregation, which starts at very low loadings, is promoted by increasing the number of P+ in the mixture. The positively charged copolymers repelled from the central part of IPEC core partially concentrate at the core-shell interface and partially escape into bulk solvent depending on the amount of P+ in the mixture and on their association number, AS. If AS is lower than the ensemble average ⟨AS⟩n, the copolymer chains released from IPEC preferentially concentrate at the core-shell interface, thus increasing AS, which approaches ⟨AS⟩n. If AS>⟨AS⟩n, they escape into the bulk solvent.
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Affiliation(s)
- Karel Šindelka
- Department of Molecular and Mesoscopic Modelling, Czech Academy of Sciences, Institute of Chemical Process Fundamentals, Rozvojová 1, 165 02 Prague, Czech Republic;
| | - Zuzana Limpouchová
- Department of Physical Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 00 Prague, Czech Republic;
| | - Karel Procházka
- Department of Physical Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 00 Prague, Czech Republic;
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Raya RK, Štěpánek M, Limpouchová Z, Procházka K, Svoboda M, Lísal M, Pavlova E, Skandalis A, Pispas S. Onion Micelles with an Interpolyelectrolyte Complex Middle Layer: Experimental Motivation and Computer Study. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c00560] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Rahul Kumar Raya
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 12840 Prague 2, Czech Republic
| | - Miroslav Štěpánek
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 12840 Prague 2, Czech Republic
| | - Zuzana Limpouchová
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 12840 Prague 2, Czech Republic
| | - Karel Procházka
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 12840 Prague 2, Czech Republic
| | - Martin Svoboda
- Department of Physics, Faculty of Science, J. E. Purkinje University, České mládeže 8, 400 96 Ústí n. Lab., Czech Republic
- Department of Molecular and Mesoscopic Modelling, Institute of Chemical Process Fundamentals of the CAS, Rozvojová 135/1, 165 02 Prague 6, Suchdol, Czech Republic
| | - Martin Lísal
- Department of Physics, Faculty of Science, J. E. Purkinje University, České mládeže 8, 400 96 Ústí n. Lab., Czech Republic
- Department of Molecular and Mesoscopic Modelling, Institute of Chemical Process Fundamentals of the CAS, Rozvojová 135/1, 165 02 Prague 6, Suchdol, Czech Republic
| | - Ewa Pavlova
- Department of Polymer Morphology, Institute of Macromolecular Chemistry of the CAS, Heyrovský Square 2, 160 00 Prague 6, Czech Republic
| | - Athanasios Skandalis
- Theoretical & Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece
| | - Stergios Pispas
- Theoretical & Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece
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Fernandez-Alvarez R, Nová L, Uhlík F, Kereïche S, Uchman M, Košovan P, Matějíček P. Interactions of star-like polyelectrolyte micelles with hydrophobic counterions. J Colloid Interface Sci 2019; 546:371-380. [PMID: 30933716 DOI: 10.1016/j.jcis.2019.03.054] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 03/15/2019] [Accepted: 03/16/2019] [Indexed: 12/26/2022]
Abstract
Hydrophobicity of a counterion has a profound effect on the interaction with polyelectrolytes similar to that of multivalency. Specifically, understanding this interaction in weak polyelectrolyte micelles might assist in developing nanocarriers for pH-controlled encapsulation and release. We used star-like weak polyelectrolyte micelles of polystyrene-block-poly(2-vinyl pyridine) (PS-P2VP) with fixed aggregation number as a model polyelectrolyte, and cobalt bis(1,2-dicarbollide) (COSAN) as a model hydrophobic anion. We used NMR to assess the mobility of the polymer segments in the presence of varying amounts of COSAN, and at varying protonation degrees of the polyelectrolyte. Same experiments with indifferent electrolyte (NaCl) were used as a control. Furthermore, we used coarse-grained simulations to obtain a detailed picture of the effect of hydrophobic counterions on the conformation of the micelles. A small amount of hydrophobic counterions causes morphological changes within the micelles, whereas a bigger amount causes precipitation. This was confirmed both in simulations and in experiments. Furthermore, adsorption of the counterions induces ionization of the collapsed segments of the polyelectrolyte. Although the COSAN/P2VP system is rather specific, the generic model used in the coarse-grained simulations shows that the observed behavior is a consequence of synergy of hydrophobic and electrostatic attraction between polyelectrolytes and hydrophobic counterions. Our study provides general insights into the molecular mechanisms of these interactions.
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Affiliation(s)
- Roberto Fernandez-Alvarez
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Prague, Czech Republic
| | - Lucie Nová
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Prague, Czech Republic
| | - Filip Uhlík
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Prague, Czech Republic
| | - Sami Kereïche
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Prague, Czech Republic; Institute of Biology and Medical Genetics, First Faculty of Medicine, Charles University and General University Hospital in Prague, Purkynie Ustav, Albertov 4, 12 801 Prague, Czech Republic
| | - Mariusz Uchman
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Prague, Czech Republic
| | - Peter Košovan
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Prague, Czech Republic.
| | - Pavel Matějíček
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Prague, Czech Republic.
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Callaway CP, Lee SM, Mallard M, Clark B, Jang SS. Effect of Block Length and Side Chain Length Ratios on Determining a Multicompartment Micelle Structure. J Phys Chem B 2019; 123:4784-4791. [PMID: 31082229 DOI: 10.1021/acs.jpcb.9b02231] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Previous work has identified the importance of the lipophilic-fluorophilic block length ratio Rl in predicting the morphology of linear lipophilic-hydrophilic-fluorophilic (hereafter referred to as BAC) micelle systems. Here, a generalized form R of this structural parameter is developed that makes no assumption of BAC triblock co-polymer linearity, while still providing accurate predictions of the micelle morphology. The morphologies of BAC micelles formed by triblock co-polymers with R≪1 or R≫1 have similar features, with the only notable difference being an inversion of the lipophilic and fluorophilic regions. A destabilization of the single-core micelle structure occurs as R approaches unity from either direction. Finally, the extent to which the micelle morphology depends on the polymer architecture instead of the composition alone is examined, with a decreased patchiness observed in BAC systems with very long block lengths. Through the modification of both the R -value and the polymer architecture, the micelle morphology can be effectively tuned for use in immobilized catalysis and nanoreactor applications.
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Affiliation(s)
- Connor P Callaway
- Computational NanoBio Technology Laboratory, School of Materials Science and Engineering , Georgia Institute of Technology , 771 Ferst Drive NW , Atlanta , Georgia 30332-0245 , United States
| | - Seung Min Lee
- Computational NanoBio Technology Laboratory, School of Materials Science and Engineering , Georgia Institute of Technology , 771 Ferst Drive NW , Atlanta , Georgia 30332-0245 , United States
| | - Mackenzie Mallard
- Computational NanoBio Technology Laboratory, School of Materials Science and Engineering , Georgia Institute of Technology , 771 Ferst Drive NW , Atlanta , Georgia 30332-0245 , United States
| | - Benjamin Clark
- Computational NanoBio Technology Laboratory, School of Materials Science and Engineering , Georgia Institute of Technology , 771 Ferst Drive NW , Atlanta , Georgia 30332-0245 , United States
| | - Seung Soon Jang
- Computational NanoBio Technology Laboratory, School of Materials Science and Engineering , Georgia Institute of Technology , 771 Ferst Drive NW , Atlanta , Georgia 30332-0245 , United States
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7
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Callaway CP, Bond N, Hendrickson K, Lee SM, Jang SS. Structural Tunability of Multicompartment Micelles as a Function of Lipophilic–Fluorophilic Block Length Ratio. J Phys Chem B 2018; 122:12164-12172. [DOI: 10.1021/acs.jpcb.8b07769] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Connor P. Callaway
- Computational NanoBio Technology Laboratory, School of Materials Science and Engineering, Georgia Institute of Technology, 771 Ferst Drive NW, Atlanta, Georgia 30332-0245, United States
| | - Nicholas Bond
- Computational NanoBio Technology Laboratory, School of Materials Science and Engineering, Georgia Institute of Technology, 771 Ferst Drive NW, Atlanta, Georgia 30332-0245, United States
| | - Kayla Hendrickson
- Computational NanoBio Technology Laboratory, School of Materials Science and Engineering, Georgia Institute of Technology, 771 Ferst Drive NW, Atlanta, Georgia 30332-0245, United States
| | - Seung Min Lee
- Computational NanoBio Technology Laboratory, School of Materials Science and Engineering, Georgia Institute of Technology, 771 Ferst Drive NW, Atlanta, Georgia 30332-0245, United States
| | - Seung Soon Jang
- Computational NanoBio Technology Laboratory, School of Materials Science and Engineering, Georgia Institute of Technology, 771 Ferst Drive NW, Atlanta, Georgia 30332-0245, United States
- Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, Georgia, United States
- Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia, United States
- Strategic Energy Institute, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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8
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Lísal M, Šindelka K, Suchá L, Limpouchová Z, Procházka K. Dissipative particle dynamics simulations of polyelectrolyte self-assemblies. Methods with explicit electrostatics. POLYMER SCIENCE SERIES C 2017. [DOI: 10.1134/s1811238217010052] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Šindelka K, Limpouchová Z, Štěpánek M, Procházka K. Stabilization of coated inorganic nanoparticles by amphiphilic copolymers in aqueous media. Dissipative particle dynamics study. Colloid Polym Sci 2017. [DOI: 10.1007/s00396-017-4090-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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10
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Dag A, Lu H, Stenzel M. Controlling the morphology of glyco-nanoparticles in water using block copolymer mixtures: the effect on cellular uptake. Polym Chem 2015. [DOI: 10.1039/c5py01360g] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Poly[(2-(α-d-mannosyloxy)ethyl acrylate)-block-(n-butyl acrylate)], P(ManA-b-BA), and poly[poly(ethylene glycol) methyl ether acrylate]-block-(n-butyl acrylate)], P(OEGMEA-b-BA) diblock copolymers were mixed at various ratios to generate self-assembled structures of different morphologies.
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Affiliation(s)
- Aydan Dag
- Centre for Advanced Macromolecular Design (CAMD)
- The University of New South Wales
- Sydney
- Australia
- Faculty of Pharmacy
| | - Hongxu Lu
- Centre for Advanced Macromolecular Design (CAMD)
- The University of New South Wales
- Sydney
- Australia
| | - Martina Stenzel
- Centre for Advanced Macromolecular Design (CAMD)
- The University of New South Wales
- Sydney
- Australia
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Posel Z, Limpouchová Z, Šindelka K, Lísal M, Procházka K. Dissipative Particle Dynamics Study of the pH-Dependent Behavior of Poly(2-vinylpyridine)-block-poly(ethylene oxide) Diblock Copolymer in Aqueous Buffers. Macromolecules 2014. [DOI: 10.1021/ma402293c] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Zbyšek Posel
- E. Hála Laboratory
of Thermodynamics, Institute of Chemical Process Fundamentals of the ASCR, v. v. i., Rozvojová 135/1, 165 02 Prague 6-Suchdol, Czech Republic
- Department of Informatics, Faculty of Science, J. E. Purkinje University, České Mládeže 8, 400 96 Ústí n. Lab., Czech Republic
| | - Zuzana Limpouchová
- Department of Physical and Macromolecular
Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 128 40 Prague 2, Czech Republic
| | - Karel Šindelka
- Department of Physical and Macromolecular
Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 128 40 Prague 2, Czech Republic
| | - Martin Lísal
- E. Hála Laboratory
of Thermodynamics, Institute of Chemical Process Fundamentals of the ASCR, v. v. i., Rozvojová 135/1, 165 02 Prague 6-Suchdol, Czech Republic
- Department of Physics, Faculty of Science, J. E. Purkinje University, České Mládeže 8, 400 96 Ústí n. Lab., Czech Republic
| | - Karel Procházka
- Department of Physical and Macromolecular
Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 128 40 Prague 2, Czech Republic
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Foster T. Universal Analytical Scattering Form Factor for Shell–, Core–Shell, or Homogeneous Particles with Continuously Variable Density Profile Shape. J Phys Chem B 2011; 115:10207-17. [DOI: 10.1021/jp204136b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tobias Foster
- University of Cologne, Institute for Physical Chemistry, Luxemburger Str. 16, 50939 Cologne, Germany
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Voets IK, Leermakers FA, de Keizer A, Charlaganov M, Stuart MAC. Co-assembly Towards Janus Micelles. SELF ORGANIZED NANOSTRUCTURES OF AMPHIPHILIC BLOCK COPOLYMERS I 2010. [DOI: 10.1007/12_2010_100] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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14
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Giacomelli FC, Riegel IC, Petzhold CL, da Silveira NP, Stĕpánek P. Internal structural characterization of triblock copolymer micelles with looped corona chains. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:3487-3493. [PMID: 19708143 DOI: 10.1021/la804254k] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We report the characterization through SAXS measurements of micelles produced from a new series of block copolymers: one diblock and four triblock copolymers bearing short poly[5-(N,N-diethylamino)isoprene] and long polystyrene blocks. Micellar aggregates produced in DMF (selective solvent for polystyrene) from the same set of samples were previously successfully characterized through light scattering measurements. The X-ray scattering profiles of starlike (from the diblock copolymer sample) and flowerlike micelles (from the triblock copolymers samples) could be fitted using the spherical copolymer micelle model proposed by Pedersen and Gerstenberg (Macromolecules 1996, 29, 1363.) where in the case of flowerlike micelles, the particles were understood as formed by hypothetical diblock copolymers having half of the true polymeric molar mass. Using the spherical copolymer micelle model, it could be possible to attest the unswollen nature of the micellar cores. The total micellar size suggested thus that the chains forming the corona are extended which is mainly related to a small core surface area per corona chain entering the core (Ac/n), which also induced a small number of aggregation (N(agg)) of all self-assembled particles. The total micellar size fits well with our previous light scattering measurements.
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Affiliation(s)
- Fernando C Giacomelli
- Institute of Chemistry, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, 91501-970 Porto Alegre, Brazil
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15
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Chen X, Matteucci ME, Lo CY, Johnston KP, Williams RO. Flocculation of Polymer Stabilized Nanocrystal Suspensions to Produce Redispersible Powders. Drug Dev Ind Pharm 2009; 35:283-96. [DOI: 10.1080/03639040802282896] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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16
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Procházka K, Matějíček P, Uchman M, Štěpánek M, Humpolíčková J, Hof M, Špírková M. pH-Dependent Behavior of Hydrophobically Modified Polyelectrolyte Shells of Polymeric Nanoparticles. ACTA ACUST UNITED AC 2008. [DOI: 10.1002/masy.200851313] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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17
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Jelínek K, Limpouchová Z, Uhlík F, Procházka K. SCF Study of Amphiphilic Micellar Shells Containing Polyelectrolyte and Hydrophobic Sequences. Macromolecules 2007. [DOI: 10.1021/ma070928c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Karel Jelínek
- Department of Physical and Macromolecular Chemistry & Laboratory of Specialty Polymers, Charles University in Prague, Faculty of Science, Albertov 6, 128 43 Praha 2, Czech Republic
| | - Zuzana Limpouchová
- Department of Physical and Macromolecular Chemistry & Laboratory of Specialty Polymers, Charles University in Prague, Faculty of Science, Albertov 6, 128 43 Praha 2, Czech Republic
| | - Filip Uhlík
- Department of Physical and Macromolecular Chemistry & Laboratory of Specialty Polymers, Charles University in Prague, Faculty of Science, Albertov 6, 128 43 Praha 2, Czech Republic
| | - Karel Procházka
- Department of Physical and Macromolecular Chemistry & Laboratory of Specialty Polymers, Charles University in Prague, Faculty of Science, Albertov 6, 128 43 Praha 2, Czech Republic
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18
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Kaewsaiha P, Matsumoto K, Matsuoka H. Sphere-to-rod transition of non-surface-active amphiphilic diblock copolymer micelles: a small-angle neutron scattering study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:9162-9. [PMID: 17676775 DOI: 10.1021/la7003672] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Micellization behavior of amphiphilic diblock copolymers with strong acid groups, poly(hydrogenated isoprene)-block-poly(styrenesulfonate), was investigated by small-angle neutron scattering (SANS). We have reported previously (Kaewsaiha, P.; Matsumoto, K.; Matsuoka, H. Langmuir 2005, 21, 9938) that this strongly ionic amphiphilic diblock copolymer shows almost no surface activity but forms micelles in water. In this study, the size, shape, and internal structures of the micelles formed by these unique copolymers in aqueous solution were duly investigated. The SANS data were well described by the theoretical form factor of a core-shell model and the Pedersen core-corona model. The micellar shape strongly depends on the hydrophobic chain length of the block copolymer. The polymer with the shortest hydrophobic chain was suggested to form spherical micelles, whereas the scattering curves of the longer hydrophobic chain polymers showed a q-1 dependence, reflecting the formation of rodlike micelles. Furthermore, the addition of salt at high concentration also induced the sphere-to-rod transition in micellar shape as a result of the shielding effect of electrostatic repulsion. The corona thickness was almost constant up to the critical salt concentration (around 0.2 M) and then decreased with further increases in salt concentration, which is in qualitatively agreement with existing theories. The spherical/rodlike micelle ratio was also constant up to the critical salt concentration and then decreased. The micelle size and shape of this unique polymer could be described by the common concept of the packing parameter, but the anomalously stable nature of the micelle (up to 1 M NaCl) is a special characteristic.
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Pleštil J, Koňák Č, Hu X, Lal J. Study of Comicellization of Diblock Copolymers in a Selective Solvent. MACROMOL CHEM PHYS 2006. [DOI: 10.1002/macp.200500438] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Matějíček P, Štěpánek M, Uchman M, Procházka K, Špírková M. Atomic Force Microscopy and Light Scattering Study of Onion-Type Micelles Formed by Polystyrene-block-poly(2-vinylpyridine) and Poly(2-vinylpyridine)-block-poly(ethylene oxide) Copolymers in Aqueous Solutions. ACTA ACUST UNITED AC 2006. [DOI: 10.1135/cccc20060723] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The three-layer onion micelles formed in aqueous solution by hierarchical self-assembly of polystyrene-block-poly(2-vinylpyridine) micelles, PS-PVP, and poly(2-vinylpyridine)-block-poly(ethylene oxide) chains, PVP-PEO, were studied by a combination of light scattering (LS) and atomic force microscopy (AFM). Section analysis of AFM images of micelles deposited on mica in combination with LS data from micellar solutions provide distribution functions of sizes from which the number and mass distributions of molar masses of micelles can be evaluated. Both light scattering and AFM data reveal that the used preparation protocol yields onion micelles accompanied by an admixture of PVP-PEO micelles. It means that only a certain amount of PVP-PEO self-assembles with PS-PVP and forms onion micelles. The remaining PVP-PEO copolymer forms either small PVP-PEO micelles or participates in formation of large aggregates at longer times. The time-dependent measurements show that both onion-type and core-shell PVP-PEO micelles are fairly stable over a long time period and only a low fraction of large aggregate forms on the timescale of weeks and at longer times, the solution does not change any more.
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Fustin CA, Abetz V, Gohy JF. Triblock terpolymer micelles: a personal outlook. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2005; 16:291-302. [PMID: 15696269 DOI: 10.1140/epje/i2004-10086-0] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2004] [Accepted: 01/04/2005] [Indexed: 05/24/2023]
Abstract
This outlook paper focuses on micelles formed by ABC triblock copolymers (triblock terpolymers) and related systems resulting from mixtures of diblock copolymers. Micelles with different internal structure such as micelles with a heterogeneous core and a homogeneous corona or micelles with a homogeneous core and a mixed corona are presented. More complex nanoobjects such as vesicles and Janus particles are also reviewed. Finally, potential applications of these objects are discussed.
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Affiliation(s)
- C A Fustin
- Unité de Chimie des Matériaux Inorganiques et Organiques and Research Center in Micro- and Nano-Materials and Electronic Devices (CeRMiN), Université catholique de Louvain, Place L. Pasteur 1, B-1348 Louvain-la-Neuve, Belgium
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Matějíček P, Podhájecká K, Humpolíčková J, Uhlík F, Jelínek K, Limpouchová Z, Procházka K, Špírková M. Polyelectrolyte Behavior of Polystyrene-block-poly(methacrylic acid) Micelles in Aqueous Solutions at Low Ionic Strength. Macromolecules 2004. [DOI: 10.1021/ma049258q] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Pavel Matějíček
- Department of Physical and Macromolecular Chemistry & Laboratory of Specialty Polymers, School of Science, Charles University in Prague, Albertov 6, 128 43 Prague 2, Czech Republic
| | - Klára Podhájecká
- Department of Physical and Macromolecular Chemistry & Laboratory of Specialty Polymers, School of Science, Charles University in Prague, Albertov 6, 128 43 Prague 2, Czech Republic
| | - Jana Humpolíčková
- Department of Physical and Macromolecular Chemistry & Laboratory of Specialty Polymers, School of Science, Charles University in Prague, Albertov 6, 128 43 Prague 2, Czech Republic
| | - Filip Uhlík
- Department of Physical and Macromolecular Chemistry & Laboratory of Specialty Polymers, School of Science, Charles University in Prague, Albertov 6, 128 43 Prague 2, Czech Republic
| | - Karel Jelínek
- Department of Physical and Macromolecular Chemistry & Laboratory of Specialty Polymers, School of Science, Charles University in Prague, Albertov 6, 128 43 Prague 2, Czech Republic
| | - Zuzana Limpouchová
- Department of Physical and Macromolecular Chemistry & Laboratory of Specialty Polymers, School of Science, Charles University in Prague, Albertov 6, 128 43 Prague 2, Czech Republic
| | - Karel Procházka
- Department of Physical and Macromolecular Chemistry & Laboratory of Specialty Polymers, School of Science, Charles University in Prague, Albertov 6, 128 43 Prague 2, Czech Republic
| | - Milena Špírková
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovský Square 2, 162 06 Prague 6, Czech Republic
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Uhlík F, Limpouchová Z, Jelínek K, Procházka K. Polyelectrolyte shells of copolymer micelles in aqueous solutions: A Monte Carlo study. J Chem Phys 2004; 121:2367-75. [PMID: 15260791 DOI: 10.1063/1.1763571] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Multimolecular micelles, formed by polystyrene-block-poly(methacrylic acid) in water, are studied by lattice Monte Carlo method. Electrostatic interactions are calculated in the mean-field approximation by solving the Poisson-Boltzmann equation. The model is parametrized according to available experimental data. The dependence of micellar size on pH and ionic strength is calculated and compared with experimental data. A special attention is devoted to the behavior in solutions with a low ionic strength.
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Affiliation(s)
- Filip Uhlík
- Department of Physical and Macromolecular Chemistry, School of Science, Charles University, Albertov 6, 128 43 Praha 2, Czech Republic
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Hahn J, Webber SE. Deposition of cationic polymer micelles on planar SiO2 surfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:4211-9. [PMID: 15969419 DOI: 10.1021/la035819f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The deposition of PS-PVPH+ polymer micelles from a pH 1 aqueous solution onto Si wafers has been studied using a simple dip-coating technique. It has been found that the rate of evaporation of the solvent and the rate of withdrawal have a considerable influence on the density and ordering of the adsorbed micelles. The highest density and degree of ordering (as judged by the 2D pair correlation function) is achieved when solvent evaporation dominates the deposition process, but a fairly homogeneous distribution of polymer micelles can be achieved over a distance of at least 3-4 mm by controlling the solvent evaporation rate and the rate of substrate withdrawal. We did not observe any significant effect of added KCl (up to 0.1 M) during the deposition process or soaking in 1 M KCl after deposition. The attachment of these micelles is quite robust, as they cannot be washed off in pH 1 water (with or without KCl) without significant mechanical assistance. However, we did find that the micelles are rather easily caused to dewet and partially aggregate under the influence of 65 degrees C water vapor.
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Affiliation(s)
- Jungseok Hahn
- Department of Chemistry and Biochemistry, Center for Nano- and Molecular Science and Technology, The University of Texas at Austin, Austin, Texas 78712, USA
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Hahn J, Webber SE. Graphoepitaxial deposition of cationic polymer micelles on patterned SiO2 surfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:1489-1494. [PMID: 15803739 DOI: 10.1021/la035950n] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We have studied the deposition of polymer micelles formed from poly(styrene)-block-poly(2-vinylpyridine) (PS-PVPH+) from room-temperature aqueous solutions at pH 1 onto a hydrophilic Si/SiO2 surface with a relief pattern 100 nm deep with variable widths. It has been found that the micelle density is substantially higher and the ordering of the micelles is improved for micelles that adsorb in the 100 nm depressions in the width range of ca. 500-5000 nm. We ascribe these effects to capillary forces that pull the aqueous solution into the canyons where the micelles can be trapped. While the ordering of the micelles can be substantial, they do not form a perfect hexagonal crystal. If the surface is chemically modified by a Au coating, the micelle-surface interaction is strengthened and the degree of ordering is diminished. These results demonstrate that a combination of graphoepitaxy and processing conditions (speed of substrate withdrawal or evaporation of solvent) can be used to make fairly ordered polymer micelle arrays over a space of (at least) several millimeters.
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Affiliation(s)
- Jungseok Hahn
- Department of Chemistry and Biochemistry and Center for Nano- and Molecular Science and Technology, The University of Texas at Austin, Austin, Texas 78712, USA
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Uhlı́k F, Limpouchová Z, Jelı́nek K, Procházka K. A Monte Carlo study of shells of hydrophobically modified amphiphilic copolymer micelles in polar solvents. J Chem Phys 2003. [DOI: 10.1063/1.1575732] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Pedersen JS, Gerstenberg MC. The structure of P85 Pluronic block copolymer micelles determined by small-angle neutron scattering. Colloids Surf A Physicochem Eng Asp 2003. [DOI: 10.1016/s0927-7757(02)00511-3] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Štěpánek M, Humpolíčková J, Procházka K, Hof M, Tuzar Z, Špírková M, Wolff T. Light Scattering, Atomic Force Microscopy and Fluorescence Correlation Spectroscopy Studies of Polystyrene-block-poly(2-vinylpyridine)-block-poly(ethylene oxide) Micelles. ACTA ACUST UNITED AC 2003. [DOI: 10.1135/cccc20032120] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Polymeric nanoparticles formed by triblock copolymer polystyrene-block-poly(2-vinylpyridine)-block-poly(ethylene oxide), PS-PVP-PEO, in aqueous media were studied by a combination of fluorescence correlation spectroscopy with other fluorescence techniques, light scattering and atomic force microscopy. The studied polymeric nanoparticles exist in the form of (i) core/shell micelles in acid solution at pH lower than 4.8 and (ii) three-layer onion micelles at higher pH. Since water is a very strong precipitant for PS, both types of micelles have kinetically frozen spherical PS cores. The cores of micelles in acid media are surrounded by soluble shells formed by partly protonated PVP and PEO, while the cores of micelles in alkaline media are surrounded by compact insoluble layers of deprotonated PVP and soluble PEO shells. The micellization behavior of PS-PVP-PEO micelles is accompanied by secondary aggregation of micelles, which is provoked by stirring, shaking and also by filtration of micellar solutions. Therefore fluorescence correlation spectroscopy (FCS), which, in contrast to light scattering techniques, does not require filtration, was used as the main experimental technique for the characterization of non-aggregated micelles. The binding of a fluorescence probe, octadecylrhodamine B (ORB), to polymeric micelles, was studied before the FCS study of micelles.
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Pedersen JS, Svaneborg C, Almdal K, Hamley IW, Young RN. A Small-Angle Neutron and X-ray Contrast Variation Scattering Study of the Structure of Block Copolymer Micelles: Corona Shape and Excluded Volume Interactions. Macromolecules 2002. [DOI: 10.1021/ma0204913] [Citation(s) in RCA: 135] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jan Skov Pedersen
- Department of Chemistry, University of Aarhus, DK-8000 Aarhus C, Denmark, Danish Polymer Center, Risø National Laboratory, DK-4000 Roskilde, Denmark, School of Chemistry, University of Leeds, Leeds LS2 9JT, W. Yorkshire, England, and Department of Chemistry, University of Sheffield, Sheffield S3 7HF, S. Yorkshire, England
| | - Carsten Svaneborg
- Department of Chemistry, University of Aarhus, DK-8000 Aarhus C, Denmark, Danish Polymer Center, Risø National Laboratory, DK-4000 Roskilde, Denmark, School of Chemistry, University of Leeds, Leeds LS2 9JT, W. Yorkshire, England, and Department of Chemistry, University of Sheffield, Sheffield S3 7HF, S. Yorkshire, England
| | - Kristoffer Almdal
- Department of Chemistry, University of Aarhus, DK-8000 Aarhus C, Denmark, Danish Polymer Center, Risø National Laboratory, DK-4000 Roskilde, Denmark, School of Chemistry, University of Leeds, Leeds LS2 9JT, W. Yorkshire, England, and Department of Chemistry, University of Sheffield, Sheffield S3 7HF, S. Yorkshire, England
| | - Ian W. Hamley
- Department of Chemistry, University of Aarhus, DK-8000 Aarhus C, Denmark, Danish Polymer Center, Risø National Laboratory, DK-4000 Roskilde, Denmark, School of Chemistry, University of Leeds, Leeds LS2 9JT, W. Yorkshire, England, and Department of Chemistry, University of Sheffield, Sheffield S3 7HF, S. Yorkshire, England
| | - Ron N. Young
- Department of Chemistry, University of Aarhus, DK-8000 Aarhus C, Denmark, Danish Polymer Center, Risø National Laboratory, DK-4000 Roskilde, Denmark, School of Chemistry, University of Leeds, Leeds LS2 9JT, W. Yorkshire, England, and Department of Chemistry, University of Sheffield, Sheffield S3 7HF, S. Yorkshire, England
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Uhlík F, Limpouchová Z, Matějíček P, Procházka K, Tuzar Z, Webber SE. Nonradiative Excitation Energy Transfer in Hydrophobically Modified Amphiphilic Block Copolymer Micelles. Theoretical Model and Monte Carlo Simulations,. Macromolecules 2002. [DOI: 10.1021/ma012073o] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Filip Uhlík
- Department of Physical and Macromolecular Chemistry & Laboratory of Specialty Polymers, School of Science, Charles University in Prague, Albertov 6, 128 43 Prague 2, Czech Republic
| | - Zuzana Limpouchová
- Department of Physical and Macromolecular Chemistry & Laboratory of Specialty Polymers, School of Science, Charles University in Prague, Albertov 6, 128 43 Prague 2, Czech Republic
| | - Pavel Matějíček
- Department of Physical and Macromolecular Chemistry & Laboratory of Specialty Polymers, School of Science, Charles University in Prague, Albertov 6, 128 43 Prague 2, Czech Republic
| | - Karel Procházka
- Department of Physical and Macromolecular Chemistry & Laboratory of Specialty Polymers, School of Science, Charles University in Prague, Albertov 6, 128 43 Prague 2, Czech Republic
| | - Zdeněk Tuzar
- Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovský Square 2, 162 06 Prague 6, Czech Republic
| | - Stephen E. Webber
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712
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Castelletto V, Hamley I. Modelling small-angle scattering data from micelles. Curr Opin Colloid Interface Sci 2002. [DOI: 10.1016/s1359-0294(02)00043-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Matějíček P, Uhlík F, Limpouchová Z, Procházka K, Tuzar Z, Webber SE. Hydrophobically Modified Amphiphilic Block Copolymer Micelles in Non-Aqueous Polar Solvents. Fluorometric, Light Scattering and Computer-Based Monte Carlo Study. ACTA ACUST UNITED AC 2002. [DOI: 10.1135/cccc20020531] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The micellization behavior of a hydrophobically modified polystyrene-block-poly(methacrylic acid) diblock copolymer, PS-N-PMA-A, tagged with naphthalene between blocks and with anthracene at the end of the PMA block, was studied in 1,4-dioxane-methanol mixtures by light scattering and fluorescence techniques. The behavior of a single-tagged sample, PS-N-PMA, and low-molar-mass analogues was studied for comparison. Methanol-rich mixtures with 1,4-dioxane are strong selective precipitants for PS. Multimolecular micelles with compact PS cores and PMA shells may be prepared indirectly by dialysis from 1,4-dioxane-rich mixtures, or by a slow titration of copolymer solutions in 1,4-dioxane-rich solvents with methanol under vigorous stirring. In tagged micelles, the naphthalene tag is trapped in nonpolar and fairly viscous core/shell interfacial region. In hydrophobically modified PS-N-PMA-A micelles, the hydrophobic anthracene at the ends of PMA blocks tends to avoid the bulk polar solvent and buries in the shell. The distribution of anthracene tags in the shell is a result of the enthalpy-to-entropy interplay. The measurements of direct nonradiative excitation energy transfer were performed to estimate the distribution of anthracene-tagged PMA ends in the shell. The experimental fluorometric data show that anthracene tags penetrate into the inner shell in methanol-rich solvents. Monte Carlo simulations were performed on model systems to get reference data for analysis of time-resolved fluorescence decay curves. A comparison of experimental and simulated decays indicates that hydrophobic traps return significantly deep into the shell (although not as deep as in aqueous media). The combined light scattering, fluorometric and computer simulation study shows that the conformational behavior of shell-forming PMA blocks in non-aqueous media is less affected by the presence of nonpolar traps than that in aqueous media.
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