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Edatholath SS, Chandan MR, Aswal VK, Rath SK, Harikrishnan G. Hydration influences on the phase heterogeneity of segmented copolymers. SOFT MATTER 2021; 17:1850-1860. [PMID: 33404044 DOI: 10.1039/d0sm01287d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We elucidate the influences of hydration on the morphological heterogeneity of the class of hard-soft segmented copolymers by experimenting on three model members selected from this group. For influences on phase segmentation, we quantify the degree of phase separation, segment boundary diffusiveness and extent of interphase mixing. Qualitative variations induced by hydration in hydrogen bonding within the phases are also mapped. An inverse relationship between the degree of segmentation and inherent water miscibility of the polymer backbones is observed, that is, high miscibility reducing the degree of segmentation, whereas poor miscibility increasing it. We then quantify hydration induced variations in the size, volume fraction and interaction pair potentials of individual hard segments. The influences on hard segment assemblies are assessed by quantifying their size, volume fraction, interaction pair potential and intrasegment adhesion. This quantification reveals a complex interplay between the volume expansion of individual hard segments and simultaneous swelling and disassembly of their assemblies. Finally, we integrate the segmentation parameters with observed alterations in hydrogen bonding and the inherent polarizability of segments to present a mechanism that reasonably describes the hydrated state morphology. Besides revealing the influences of hydration on the morphological heterogeneity of this class of polymers, our insights give strategies for new synthesis methods for water contact applications and aids in predicting their hydration induced thermomechanical property alterations.
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Affiliation(s)
- Saji S Edatholath
- Department of Chemical Engineering, Indian Institute of Technology Kharagpur, West Bengal 721302, India.
| | - Mohammed R Chandan
- Department of Chemical Engineering, Indian Institute of Technology Kharagpur, West Bengal 721302, India.
| | - Vinod K Aswal
- Solid State Physics Division, Bhabha Atomic Research Center, Mumbai, 400085, India
| | - Sangram K Rath
- Naval Materials Research Laboratory, Ambernath, Maharashtra 421506, India
| | - G Harikrishnan
- Department of Chemical Engineering, Indian Institute of Technology Kharagpur, West Bengal 721302, India.
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Heo TY, Kim I, Chen L, Lee E, Lee S, Choi SH. Effect of Ionic Group on the Complex Coacervate Core Micelle Structure. Polymers (Basel) 2019; 11:E455. [PMID: 30960439 PMCID: PMC6473896 DOI: 10.3390/polym11030455] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 02/22/2019] [Accepted: 02/27/2019] [Indexed: 12/16/2022] Open
Abstract
Pairs of ionic group dependence of the structure of a complex coacervate core micelle (C3M) in an aqueous solution was investigated using DLS, cryo-TEM, and SANS with a contrast matching technique and a detailed model analysis. Block copolyelectrolytes were prepared by introducing an ionic group (i.e., ammonium, guanidinium, carboxylate, and sulfonate) to poly(ethylene oxide-b-allyl glycidyl ether) (NPEO = 227 and NPAGE = 52), and C3Ms were formed by simple mixing of two oppositely-charged block copolyelectrolyte solutions with the exactly same degree of polymerization. All four C3Ms are spherical with narrow distribution of micelle dimension, and the cores are significantly swollen by water, resulting in relatively low brush density of PEO chains on the core surface. With the pair of strong polyelectrolytes, core radius and aggregation number increases, which reflects that the formation of complex coacervates are significantly sensitive to the pairs of ionic groups rather than simple charge pairing.
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Affiliation(s)
- Tae-Young Heo
- Department of Chemical Engineering, Hongik University, Seoul 04066, Korea.
| | - Inhye Kim
- Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon 34134, Korea.
| | - Liwen Chen
- Department of Chemical & Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
| | - Eunji Lee
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Korea.
| | - Sangwoo Lee
- Department of Chemical & Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
| | - Soo-Hyung Choi
- Department of Chemical Engineering, Hongik University, Seoul 04066, Korea.
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Zhou C, Toombes GES, Wasbrough MJ, Hillmyer MA, Lodge TP. Structure of Two-Compartment Hydrogels from Thermoresponsive ABC Triblock Terpolymers. Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b00584] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
| | - Gilman E. S. Toombes
- National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Matthew J. Wasbrough
- National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
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5
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Rheology and nanostructure of hydrophobically modified alginate (HMA) gels and solutions. Carbohydr Polym 2012; 87:524-530. [DOI: 10.1016/j.carbpol.2011.08.025] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Revised: 08/04/2011] [Accepted: 08/05/2011] [Indexed: 11/21/2022]
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6
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Taribagil RR, Hillmyer MA, Lodge TP. Hydrogels from ABA and ABC Triblock Polymers. Macromolecules 2010. [DOI: 10.1021/ma100464z] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - Timothy P. Lodge
- Department of Chemical Engineering & Materials Science
- Department of Chemistry
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Choi SH, Bates FS, Lodge TP. Structure of poly(styrene-b-ethylene-alt-propylene) diblock copolymer micelles in squalane. J Phys Chem B 2010; 113:13840-8. [PMID: 19320497 DOI: 10.1021/jp8111149] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The temperature dependence of the micellar structures formed by poly(styrene-b-ethylene-alt-propylene) (SEP) diblock copolymers in squalane, a highly selective solvent for the PEP blocks, has been studied using dynamic light scattering (DLS) and small-angle X-ray scattering (SAXS). Four SEP diblock copolymers were prepared by sequential anionic polymerization of styrene and isoprene, followed by hydrogenation of the isoprene blocks, to yield SEP(17-73), SEP(26-66), SEP(36-69), and SEP(42-60), where the numbers indicate block molecular weights in kDa. All four polymers formed well-defined spherical micelles. In dilute solution, DLS provided the temperature-dependent mean hydrodynamic radius, R(h), and its distribution, while detailed fitting of the SAXS profiles gave the core radius, R(c), the equivalent hard sphere radius, R(hs), and an estimate of the aggregation number, N(agg). In general, the micelles became smaller as the critical micelle temperature (CMT) was approached, which was well above the glass transition of the core block. As concentration increased the micelles packed onto body centered cubic lattices for all four copolymers, which underwent order-disorder transitions upon heating near the dilute solution CMTs. The results are discussed in terms of current understanding of block copolymer solution self-assembly, and particular attention is paid to the issue of equilibration, given the high glass transition temperature of the core block.
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Affiliation(s)
- Soo-Hyung Choi
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, USA
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Piogé S, Fontaine L, Gaillard C, Nicol E, Pascual S. Self-Assembling Properties of Well-Defined Poly(ethylene oxide)-b-poly(ethyl acrylate) Diblock Copolymers. Macromolecules 2009. [DOI: 10.1021/ma802705b] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sandie Piogé
- Polymères, Colloïdes, Interfaces, UMR CNRS 6120, Université du Maine, Le Mans, France
- Unité de Chimie Organique Moléculaire et Macromoléculaire, UMR CNRS 6011, Université du Maine, Le Mans, France
| | - Laurent Fontaine
- Unité de Chimie Organique Moléculaire et Macromoléculaire, UMR CNRS 6011, Université du Maine, Le Mans, France
| | - Cédric Gaillard
- Laboratoire de Microscopie, plate-forme RIO BIBS, U.R. BIA, INRA, Nantes, France
| | - Erwan Nicol
- Polymères, Colloïdes, Interfaces, UMR CNRS 6120, Université du Maine, Le Mans, France
| | - Sagrario Pascual
- Unité de Chimie Organique Moléculaire et Macromoléculaire, UMR CNRS 6011, Université du Maine, Le Mans, France
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Diblock copolymers of ethylene oxide and 1,2-butylene oxide in aqueous solution. Int J Pharm 2008; 362:193-6. [DOI: 10.1016/j.ijpharm.2008.06.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2008] [Revised: 06/02/2008] [Accepted: 06/04/2008] [Indexed: 11/20/2022]
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Castro E, Barbosa S, Juárez J, Taboada P, Katime IA, Mosquera V. Influence of External Factors on the Micellization Process and Aggregate Structure of Poly(oxy)styrene−Poly(oxy)ethylene Block Copolymers. J Phys Chem B 2008; 112:5296-304. [DOI: 10.1021/jp7112895] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Emilio Castro
- Grupo de Física de Coloides y Polímeros, Grupo de Sistemas Complejos, Departamento de Física de la Materia Condensada, Facultad de Física, Universidad de Santiago de Compostela, Santiago de Compostela, Spain, and Grupo de Nuevos Materiales y Espectroscopia Supramolecular, Departamento de Química-Física, Facultad de Ciencia y Tecnología, Campus de Leioa, Universidad del País Vasco, Apartado 644, Bilbao, Spain
| | - Silvia Barbosa
- Grupo de Física de Coloides y Polímeros, Grupo de Sistemas Complejos, Departamento de Física de la Materia Condensada, Facultad de Física, Universidad de Santiago de Compostela, Santiago de Compostela, Spain, and Grupo de Nuevos Materiales y Espectroscopia Supramolecular, Departamento de Química-Física, Facultad de Ciencia y Tecnología, Campus de Leioa, Universidad del País Vasco, Apartado 644, Bilbao, Spain
| | - Josué Juárez
- Grupo de Física de Coloides y Polímeros, Grupo de Sistemas Complejos, Departamento de Física de la Materia Condensada, Facultad de Física, Universidad de Santiago de Compostela, Santiago de Compostela, Spain, and Grupo de Nuevos Materiales y Espectroscopia Supramolecular, Departamento de Química-Física, Facultad de Ciencia y Tecnología, Campus de Leioa, Universidad del País Vasco, Apartado 644, Bilbao, Spain
| | - Pablo Taboada
- Grupo de Física de Coloides y Polímeros, Grupo de Sistemas Complejos, Departamento de Física de la Materia Condensada, Facultad de Física, Universidad de Santiago de Compostela, Santiago de Compostela, Spain, and Grupo de Nuevos Materiales y Espectroscopia Supramolecular, Departamento de Química-Física, Facultad de Ciencia y Tecnología, Campus de Leioa, Universidad del País Vasco, Apartado 644, Bilbao, Spain
| | - Issa A. Katime
- Grupo de Física de Coloides y Polímeros, Grupo de Sistemas Complejos, Departamento de Física de la Materia Condensada, Facultad de Física, Universidad de Santiago de Compostela, Santiago de Compostela, Spain, and Grupo de Nuevos Materiales y Espectroscopia Supramolecular, Departamento de Química-Física, Facultad de Ciencia y Tecnología, Campus de Leioa, Universidad del País Vasco, Apartado 644, Bilbao, Spain
| | - Víctor Mosquera
- Grupo de Física de Coloides y Polímeros, Grupo de Sistemas Complejos, Departamento de Física de la Materia Condensada, Facultad de Física, Universidad de Santiago de Compostela, Santiago de Compostela, Spain, and Grupo de Nuevos Materiales y Espectroscopia Supramolecular, Departamento de Química-Física, Facultad de Ciencia y Tecnología, Campus de Leioa, Universidad del País Vasco, Apartado 644, Bilbao, Spain
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Kelarakis A, Crassous JJ, Ballauff M, Yang Z, Booth C. Micellar spheres in a high frequency oscillatory field. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2006; 22:6814-7. [PMID: 16863225 DOI: 10.1021/la0607860] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The viscoelasticity of aqueous micellar solutions of two oxyethylene/oxybutylene block copolymers (E(92)B(18) and B(20)E(510)) has been investigated using a torsional resonator operated at 26 kHz. For both systems considered, values of the dynamic viscosity (eta'(infinity)) point to partial draining of the micellar corona induced by the high-frequency oscillatory field. At low effective volume fractions, values of the elastic modulus (G'(infinity)) indicate that the repulsive interactions between micelles can be modeled by a power law function u(r) proportional to 1/r(nu) with exponents close to 13 and 6 for copolymers E(92)B(18) and B(20)E(510) respectively. At a critical copolymer concentration (c*) plots of log(G'(infinity)) against log(c) deviate from the straight lines established at low concentrations, implying that the systems undergo ergodic/nonergodic transitions.
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Affiliation(s)
- Antonis Kelarakis
- Physikalishe Chemie I, Universität Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany.
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Castro E, Taboada P, Mosquera V. Cosolvent Effects on the Micellization of Oxyphenyl(copoly)ethylene Oxide Copolymers in Aqueous Solution. J Phys Chem B 2006; 110:13113-23. [PMID: 16805622 DOI: 10.1021/jp061322d] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In the present paper, we have analyzed how the presence of ethanol affects the micellization process of two structurally related polyoxyethylene block copolymers with diblock and triblock architectures (diblock, S15E63; triblock, E67S15E67) and the same hydrophobic block length, formed by oxyphenylethylene units, through surface tension, static and dynamic light scattering, density, ultrasound velocity, transmission electron microscopy, and steady-state fluorescence techniques. E and S denote the oxyethylene (-OCH2CH2) and oxyphenylethylene (-OCH2CH(C6H5)) units, respectively, and the subscripts the block length. The effect of increasing amounts of ethanol in solution gives rise to a progressive disruption of the micelle structures formed by these copolymers, with an increase in the critical micelle concentration (cmc) values and a decrease in the micellar aggregation number. This originated from the deswelling of the poly(ethylene oxide) (PEO) chains due to a decrease of the water content, accompanied by a reduction of the solvophobicity and an increase of the solubility of the S blocks, causing the lowering of the interfacial tension between the polyoxyphenylethylene core and the solvent, and favoring the swelling of hydrophobic blocks. Therefore, to achieve thermodynamic equilibrium, the micelle size should be smaller. A model derived from small angle neutron scattering (SANS) data is also applied to get extra information on micelle structure. With the aim of obtaining information about the hydration of micellar solutions of these block copolymers, compressibility and fluorescence data were collected. The increase of compressibility with ethanol addition confirms the swelling of the hydrophobic polyoxyphenylethylene chains. Fluorescence data show that the addition of ethanol to the solution decreases the polarity, favoring the solubilization of the oxyphenylethylene chains in the mixed solvent as single monomers. Aggregation data derived from this technique are in fair agreement with those obtained from light scattering.
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Affiliation(s)
- Emilio Castro
- Laboratorio de Física de Coloides y Polímeros, Grupo de Sistemas Complejos, Departamento de Física de la Materia Condensada, Facultad de Física, Universidad de Santiago de Compostela, Spain
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Castelletto V, Hamley IW, Yuan XF, Kelarakis A, Booth C. Structure and rheology of aqueous micellar solutions and gels formed from an associative poly(oxybutylene)-poly(oxyethylene)-poly(oxybutylene) triblock copolymer. SOFT MATTER 2005; 1:138-145. [PMID: 32521837 DOI: 10.1039/b419103j] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The structure and shear flow behaviour of aqueous micellar solutions and gels formed by an amphiphilic poly(oxybutylene)-poly(oxyethylene)-poly(oxybutylene) triblock copolymer with a lengthy hydrophilic poly(oxyethylene) block has been investigated by rheology, small angle neutron scattering (SANS) and small-angle X-ray scattering (SAXS). SANS revealed that bridging of chains between micelles introduces, in the micellar solution, an attractive long-range component which can be described through a potential of interaction corresponding to sticky soft spheres. The strength of the attractive interaction increases with increasing concentration. Rheology showed that the dependence of the storage modulus with temperature can be explained as a function of the micellar bridging, micellisation and phase morphology. SAXS studies showed that the orientation adopted by the system in the gel phase under shear is similar to that previously observed by us for the gel phase of a poly(oxyethylene)-poly(oxybutylene) diblock copolymer with a long poly(oxyethylene) chain, suggesting that the micellar corona/core length ratio and not the architecture of the block copolymer influences the alignment of the gel phase under shear.
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Affiliation(s)
- V Castelletto
- Dept of Chemistry and Centre for Self-Organising Molecular Systems, University of Leeds, Leeds LS2 9JT, UK.
| | - I W Hamley
- Dept of Chemistry and Centre for Self-Organising Molecular Systems, University of Leeds, Leeds LS2 9JT, UK.
| | - X-F Yuan
- School of Chemical Engineering and Analytical Science, University of Manchester, Manchester M60 1QD, UK
| | - A Kelarakis
- School of Chemistry, University of Manchester, Manchester M13 9PL, UK
| | - C Booth
- School of Chemistry, University of Manchester, Manchester M13 9PL, UK
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Sommer C, Pedersen JS, Garamus VM. Structure and interactions of block copolymer micelles of Brij 700 studied by combining small-angle X-ray and neutron scattering. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:2137-49. [PMID: 15752000 DOI: 10.1021/la047489k] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Spherical micelles of the diblock copolymer/surfactant Brij 700 (C(18)EO(100)) in water (D(2)O) solution have been investigated by small-angle X-ray scattering (SAXS) and small-angle neutron scattering (SANS). SAXS and SANS experiments are combined to obtain complementary information from the two different contrast conditions of the two techniques. Solutions in a concentration range from 0.25 to 10 wt % and at temperatures from 10 to 80 degrees C have been investigated. The data have been analyzed on absolute scale using a model based on Monte Carlo simulations, where the micelles have a spherical homogeneous core with a graded interface surrounded by a corona of self-avoiding, semiflexible interacting chains. SANS and SAXS data were fitted simultaneously, which allows one to obtain extensive quantitative information on the structure and profile of the core and corona, the chain interactions, and the concentration effects. The model describes the scattering data very well, when part of the EO chains are taken as a "background"contribution belonging to the solvent. The effect of this becomes non-negligible at polymer concentrations as low as 2 wt %, where overlap of the micellar coronas sets in. The results from the analysis on the micellar structure, interchain interactions, and structure factor effects are all consistent with a decrease in solvent quality of water for the PEO block as the theta temperature of PEO is approached.
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Affiliation(s)
- Cornelia Sommer
- Department of Chemistry, University of Aarhus, Langelandsgade 140, DK-8000 Aarhus C, Denmark
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Sommer C, Pedersen JS, Stein PC. Apparent Specific Volume Measurements of Poly(ethylene oxide), Poly(butylene oxide), Poly(propylene oxide), and Octadecyl Chains in the Micellar State as a Function of Temperature. J Phys Chem B 2004; 108:6242-9. [DOI: 10.1021/jp036963c] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Cornelia Sommer
- Department of Chemistry, University of Aarhus, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Jan Skov Pedersen
- Department of Chemistry, University of Aarhus, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Paul C. Stein
- Department of Chemistry, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
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Bang J, Viswanathan K, Lodge TP, Park MJ, Char K. Temperature-dependent micellar structures in poly(styrene-b-isoprene) diblock copolymer solutions near the critical micelle temperature. J Chem Phys 2004; 121:11489-500. [PMID: 15634109 DOI: 10.1063/1.1812753] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The temperature dependence of the micelle structures formed by poly(styrene-b-isoprene) (SI) diblock copolymers in the selective solvents diethyl phthalate (DEP) and tetradecane (C14), which are selective for the PS and PI blocks, respectively, have been investigated by small angle neutron scattering (SANS). Two nearly symmetric SI diblock copolymers, one with a perdeuterated PS block and the other with a perdeuterated PI block, were examined in both DEP and C14. The SANS scattering length density of the solvent was matched closely to either the core or the corona block. The resulting core and corona contrast data were fitted with a detailed model developed by Pedersen and co-workers. The fits provide quantitative information on micellar characteristics such as aggregation number, core size, overall size, solvent fraction in the core, and corona thickness. As temperature increases, the solvent selectivity decreases, leading to substantial solvent swelling of the core and a decrease in the aggregation number and core size. Both core and corona chains are able to relax their conformations near the critical micelle temperature due to a decrease in the interfacial tension, even though the corona chains are always under good solvent conditions.
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Affiliation(s)
- Joona Bang
- Department of Chemical Engineering & Materials Science, University of Minnesota, Minneapolis, MN 55455-0431, USA
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