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Rushing JC, Gurung A, Kuroda DG. Relation between microscopic structure and macroscopic properties in polyacrylonitrile-based lithium-ion polymer gel electrolytes. J Chem Phys 2023; 158:144705. [PMID: 37061496 DOI: 10.1063/5.0135631] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2023] Open
Abstract
Polymer gel electrolytes (PGE) have seen a renewed interest in their development because they have high ionic conductivities but low electrochemical degradation and flammability. PGEs are formed by mixing a liquid lithium-ion electrolyte with a polymer at a sufficiently large concentration to form a gel. PGEs have been extensively studied, but the direct connection between their microscopic structure and macroscopic properties remains controversial. For example, it is still unknown whether the polymer in the PGE acts as an inert, stabilizing scaffold for the electrolyte or it interacts with the ionic components. Here, a PGE composed of a prototypical lithium-carbonate electrolyte and polyacrylonitrile (PAN) is pursued at both microscopic and macroscopic levels. Specifically, this study focused on describing the microscopic and macroscopic changes in the PGE at different polymer concentrations. The results indicated that the polymer-ion and polymer-polymer interactions are strongly dependent on the concentration of the polymer and the lithium salt. In particular, the polymer interacts with itself at very high PAN concentrations (10% weight) resulting in a viscous gel. However, the conductivity and dynamics of the electrolyte liquid components are significantly less affected by the addition of the polymer. The observations are explained in terms of the PGE structure, which transitions from a polymer solution to a gel, containing a polymer matrix and disperse electrolyte, at low and high PAN concentrations, respectively. The results highlight the critical role that the polymer concentration plays in determining both the macroscopic properties of the system and the molecular structure of the PGE.
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Affiliation(s)
- Jeramie C Rushing
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
| | - Anit Gurung
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
| | - Daniel G Kuroda
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
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2
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Dynamics of a PEG based polymer gel Electrolyte: A combined frequency dependent dielectric relaxation and Time-resolved fluorescence spectroscopic study. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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3
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Shape-Controlled TiO 2 Nanomaterials-Based Hybrid Solid-State Electrolytes for Solar Energy Conversion with a Mesoporous Carbon Electrocatalyst. NANOMATERIALS 2021; 11:nano11040913. [PMID: 33916761 PMCID: PMC8066460 DOI: 10.3390/nano11040913] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 03/23/2021] [Accepted: 03/31/2021] [Indexed: 11/17/2022]
Abstract
One-dimensional (1D) titanium dioxide (TiO2) is prepared by hydrothermal method and incorporated as nanofiller into a hybrid polymer matrix of polyethylene glycol (PEG) and employed as a solid-electrolyte in dye-sensitized solar cells (DSSCs). Mesoporous carbon electrocatalyst with a high surface area is obtained by the carbonization of the PVDC-g-POEM double comb copolymer. The 1D TiO2 nanofiller is found to increase the photoelectrochemical performance. As a result, for the mesoporous carbon-based DSSCs, 1D TiO2 hybrid solid-state electrolyte yielded the highest efficiencies, with 6.1% under 1 sun illumination, in comparison with the efficiencies of 3.9% for quasi solid-state electrolyte and 4.8% for commercial TiO2 hybrid solid-state electrolyte, respectively. The excellent photovoltaic performance is attributed to the improved ion diffusion, scattering effect, effective path for redox couple transfer, and sufficient penetration of 1D TiO2 hybrid solid-state electrolyte into the electrode, which results in improved light-harvesting, enhanced electron transport, decreased charge recombination, and decreased resistance at the electrode/electrolyte interface.
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4
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A dynamic light scattering study of hydrogels with the addition of surfactant: a discussion of mesh size and correlation length. Polym J 2014. [DOI: 10.1038/pj.2014.114] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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5
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Yamaguchi T, Matsui R, Koda S. Relationship between microviscosity and high-frequency viscosity of polymer gel electrolytes. J Phys Chem B 2013; 117:7077-83. [PMID: 23691932 DOI: 10.1021/jp4033172] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The frequency-dependent viscosity and conductivity of polymer gel electrolytes are investigated in the megahertz region to clarify how polymer affects the ionic mobility. The electric conductivity shows no dispersion below 10 MHz, where slow dynamics of polymer are observed in shear relaxation spectra, which indicates that the ionic motion is uncorrelated with the slow dynamics of polymers that determines the steady state shear viscosity. On the other hand, the shear viscosity around 100 MHz is somewhat correlated with the direct-current (DC) molar conductivity, suggesting that the measurement of the high-frequency viscosity can be a probe of the so-called microviscosity associated with the mobility of an ion.
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Affiliation(s)
- Tsuyoshi Yamaguchi
- Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya, Aichi 464-8603, Japan.
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6
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Karatas Y, Banhatti RD, Kaskhedikar N, Burjanadze M, Funke K, Wiemhöfer HD. Synthesis and Modeling of Polysiloxane-Based Salt-in-Polymer Electrolytes with Various Additives. J Phys Chem B 2009; 113:15473-84. [DOI: 10.1021/jp907832q] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Y. Karatas
- Institute of Inorganic and Analytical Chemistry, University of Münster, Germany, Institute of Physical Chemistry, University of Münster, Germany, Department of Chemistry, Ahi Evran University, Turkey, Sonderforschungsbereich 458, University of Münster, Germany, and International Graduate School of Chemistry (GSC-MS), Germany
| | - Radha D. Banhatti
- Institute of Inorganic and Analytical Chemistry, University of Münster, Germany, Institute of Physical Chemistry, University of Münster, Germany, Department of Chemistry, Ahi Evran University, Turkey, Sonderforschungsbereich 458, University of Münster, Germany, and International Graduate School of Chemistry (GSC-MS), Germany
| | - N. Kaskhedikar
- Institute of Inorganic and Analytical Chemistry, University of Münster, Germany, Institute of Physical Chemistry, University of Münster, Germany, Department of Chemistry, Ahi Evran University, Turkey, Sonderforschungsbereich 458, University of Münster, Germany, and International Graduate School of Chemistry (GSC-MS), Germany
| | - M. Burjanadze
- Institute of Inorganic and Analytical Chemistry, University of Münster, Germany, Institute of Physical Chemistry, University of Münster, Germany, Department of Chemistry, Ahi Evran University, Turkey, Sonderforschungsbereich 458, University of Münster, Germany, and International Graduate School of Chemistry (GSC-MS), Germany
| | - K. Funke
- Institute of Inorganic and Analytical Chemistry, University of Münster, Germany, Institute of Physical Chemistry, University of Münster, Germany, Department of Chemistry, Ahi Evran University, Turkey, Sonderforschungsbereich 458, University of Münster, Germany, and International Graduate School of Chemistry (GSC-MS), Germany
| | - Hans-D. Wiemhöfer
- Institute of Inorganic and Analytical Chemistry, University of Münster, Germany, Institute of Physical Chemistry, University of Münster, Germany, Department of Chemistry, Ahi Evran University, Turkey, Sonderforschungsbereich 458, University of Münster, Germany, and International Graduate School of Chemistry (GSC-MS), Germany
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7
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Svanberg C, Uematsu T, Berntsen P, Jacobsson P. New class of dynamics in concentrated polymer gels. J Chem Phys 2007; 126:051103. [PMID: 17302464 DOI: 10.1063/1.2432884] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We show that concentrated poly(methyl methacrylate) solution exhibits a new class of coupled dynamics, which can be regarded as an intermediate between the collective diffusion of solutions and the structural relaxations of glasses. This class of dynamics have a relaxation rate that is directly proportional to the wave vector. The transition from diffusive to coupled collective dynamics occurs at smaller length scales with increasing polymer concentration and decreasing temperature. The experimental observations can be understood by considering the contributions from physical cross-links interconnected by stiff polymer segments.
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Affiliation(s)
- C Svanberg
- Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden.
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8
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Hassoun J, Reale P, Scrosati B. Recent advances in liquid and polymer lithium-ion batteries. ACTA ACUST UNITED AC 2007. [DOI: 10.1039/b707040n] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Conner DA, Welna DT, Chang Y, Allcock HR. Influence of Terminal Phenyl Groups on the Side Chains of Phosphazene Polymers: Structure−Property Relationships and Polymer Electrolyte Behavior. Macromolecules 2006. [DOI: 10.1021/ma061916e] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Denise A. Conner
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Daniel T. Welna
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Youngkyu Chang
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Harry R. Allcock
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
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11
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Sengupta B, Uematsu T, Jacobsson P, Swenson J. Exploring the antioxidant property of bioflavonoid quercetin in preventing DNA glycation: A calorimetric and spectroscopic study. Biochem Biophys Res Commun 2006; 339:355-61. [PMID: 16300739 DOI: 10.1016/j.bbrc.2005.11.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2005] [Accepted: 11/01/2005] [Indexed: 10/25/2022]
Abstract
Reducing sugars for example glucose, fructose, etc., and their phosphate derivatives non-enzymatically glycate biological macromolecules (e.g., proteins, DNA and lipids) and is related to the production of free radicals. Here we present a novel study, using differential scanning calorimetry (DSC) along with UV/Vis absorption and photon correlation spectroscopy (PCS), on normal and glycated human placenta DNA and have explored the antioxidant property of the naturally occurring polyhydroxy flavone quercetin (3,3',4',5,7-pentahydroxyflavone) in preventing the glycation. The decrease in the absorption intensity of DNA in presence of sugars clearly indicates the existence of sugar molecules between the two bases of a base pair in the duplex DNA molecule. Variations were perceptible in the PCS relaxation profiles of normal and glycated DNA. The melting temperature of placenta DNA was decreased when glycated suggesting a decrease in the structural stability of the double-stranded glycated DNA. Our DSC and PCS data showed, for the first time, that the dramatic changes in the structural properties of glycated DNA can be prevented to a significant extent by adding quercetin. This study provides valuable insights regarding the structure, function, and dynamics of normal and glycated DNA molecules, underlying the manifestation of free radical mediated diseases, and their prevention using therapeutically active naturally occurring flavonoid quercetin.
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Affiliation(s)
- Bidisa Sengupta
- Department of Applied Physics, Chalmers University of Technology, SE 41296, Göteborg, Sweden.
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12
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Andersson D, Engberg D, Swenson J, Svanberg C, Howells WS, Börjesson L. Diffusive solvent dynamics in a polymer gel electrolyte studied by quasielastic neutron scattering. J Chem Phys 2005; 122:234905. [PMID: 16008485 DOI: 10.1063/1.1931568] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A quasielastic neutron scattering study has been performed on a polymer gel electrolyte consisting of lithium perchlorate dissolved in ethylene carbonate/propylene carbonate and stabilized with poly(methyl methacrylate). The dynamics of the solvent, which is crucial for the ion conduction in this system, was probed using the hydrogen/deuterium contrast variation method with nondeuterated solvent and a deuterated polymer matrix. Two relaxation processes of the solvent were studied in the 10-400 microeV range at different temperatures. From analysis of the momentum transfer dependence of the processes we conclude that the faster process ( approximately 100 microeV) is related to rotational diffusion of the solvent and the slower process ( approximately 10 microeV) to translational diffusion of the solvent. The translational diffusion is found to be similar to the diffusion in the corresponding liquid electrolyte at short distances, but geometrically constrained by the polymer matrix at distances beyond approximately 5 A. The study indicates that the hindered diffusion of the solvent on a length scale of the polymer network interchain distance ( approximately 5-20 A) is sufficient to explain the reduced macroscopic diffusivity and ion conductivity of the gel electrolyte compared to the liquid electrolyte.
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Affiliation(s)
- D Andersson
- Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
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13
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Jansson H, Huldt C, Bergman R, Swenson J. Dynamics of water in strawberry and red onion as studied by dielectric spectroscopy. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 71:011901. [PMID: 15697624 DOI: 10.1103/physreve.71.011901] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2003] [Revised: 03/23/2004] [Indexed: 05/24/2023]
Abstract
We have investigated the microscopic dynamics of strawberry and red onion by means of broadband dielectric spectroscopy. In contrast to most of the previous experiments on carbohydrate-rich biological materials, which have mainly considered the more global dynamics of the "biological matrix," we are here focusing on the microscopic dynamics of mainly the associated water. The results for both strawberry and red onion show that the imaginary part of the permittivity contains one conductivity term and a clear dielectric loss peak, which was found to be similar to the strongest relaxation process of water in carbohydrate solutions. The temperature dependence of the relaxation process was analyzed for different water content. The relaxation process slows down, and its temperature dependence becomes more non-Arrhenius, with decreasing water content. The reason for this is most likely that, on average, the water molecules interact more strongly with carbohydrates and other biological materials at low water content, and the dynamical properties of this biological matrix changes substantially with increasing temperature (from an almost rigid matrix where the water is basically unable to perform long-range diffusion due to confinement effects, to a dynamic matrix with no static confinement effects), which also changes (i.e., reduces) the activation energy of the relaxation process with increasing temperature (i.e., causes a non-Arrhenius temperature dependence). This further changes the conductivity from mainly polarization effects at low temperatures, due to hindered ionic motions, to long-range diffusivity at T>250 K . Thus, around this temperature ions in the carbohydrate solution no longer get stuck in confined cavities, since the motion of the biological matrix "opens up" the cavities and the ions are then able to perform long-range migration.
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Affiliation(s)
- H Jansson
- Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
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14
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Scrosati B. Power sources for portable electronics and hybrid cars: lithium batteries and fuel cells. CHEM REC 2005; 5:286-97. [PMID: 16211622 DOI: 10.1002/tcr.20054] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The activities in progress in our laboratory for the development of batteries and fuel cells for portable electronics and hybrid car applications are reviewed and discussed. In the case of lithium batteries, the research has been mainly focused on the characterization of new electrode and electrolyte materials. Results related to disordered carbon anodes and improved, solvent-free, as well as gel-type, polymer electrolytes are particularly stressed. It is shown that the use of proper gel electrolytes, in combination with suitable electrode couples, allows the development of new types of safe, reliable, and low-cost lithium ion batteries which appear to be very promising power sources for hybrid vehicles. Some of the technologies proven to be successful in the lithium battery area are readapted for use in fuel cells. In particular, this approach has been followed for the preparation of low-cost and stable protonic membranes to be proposed as an alternative to the expensive, perfluorosulfonic membranes presently used in polymer electrolyte membrane fuel cells (PEMFCs).
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Affiliation(s)
- Bruno Scrosati
- Dipartimento di Chimica, Università di Roma La Sapienza, 00185 Rome, Italy.
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15
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Meneghetti P, Qutubuddin S, Webber A. Synthesis of polymer gel electrolyte with high molecular weight poly(methyl methacrylate)–clay nanocomposite. Electrochim Acta 2004. [DOI: 10.1016/j.electacta.2004.06.023] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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16
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Characterisation and modelling of the transport properties in lithium battery gel electrolytes. Electrochim Acta 2004. [DOI: 10.1016/j.electacta.2004.03.020] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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17
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Peng S, Selser JC, Bogoslovov R, Piet G. An investigation of a sol-gel/melt transition: The poly(ethylene oxide)/methanol/LiClO4 system. J Chem Phys 2004; 120:8841-52. [PMID: 15267816 DOI: 10.1063/1.1697386] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The crossover behavior of 50 000 molar mass poly(ethylene oxide)/methanol solutions from dilute solution to the melt/gel was examined. At first this behavior was investigated without LiClO(4) and then reexamined with LiClO(4). To better understand this behavior, the dependencies of dynamic light scattering (specifically, photon correlation spectroscopy) measurement results on polymer concentration, on the scattering wave vector and on temperature, and the dependence of static light scattering results on the scattering wave vector were studied. This study produced interesting and important results about network structure and behavior in poly(ethylene oxide) solutions and melts generally and about the effects of LiClO(4) on this structure and behavior more particularly.
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Affiliation(s)
- Shufu Peng
- Department of Physics, University of Nevada, Las Vegas, Las Vegas, Nevada 89154-4002, USA
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Uematsu T, Svanberg C, Nydén M, Jacobsson P. Power laws in polymer solution dynamics. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2003; 68:051803. [PMID: 14682813 DOI: 10.1103/physreve.68.051803] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2003] [Indexed: 05/24/2023]
Abstract
The dynamical screening length xi(h) in semidilute to highly concentrated polymer solutions of poly(methyl methacrylate) in propylene carbonate has been examined using photon correlation spectroscopy and pulsed field gradient nuclear magnetic resonance. A crossover between different concentration dependent regimes, xi(h) approximately phi(-alpha), where alpha is found to be approximately 0.5, approximately 1, and approximately 2, is observed when the local viscosity is taken into account. Here phi is the volume fraction of polymer in the solution. Well-defined crossovers between alpha=0.5 and alpha=1 corresponding to a transition from a marginal solvent to a theta solvent behavior have been predicted to occur due to the reduction of excluded-volume effects between the spatially correlated polymer segments with increasing polymer volume fraction. However, a clear experimental validation of the crossover has never been presented before. The third regime (alpha approximately 2) is observed in the highly concentrated region where the static screening length is comparable to the persistence length of the polymer. The observation indicates that the rigid rod model previously used to describe concentrated solutions is an oversimplification valid only in the very high concentration limit. The obtained results at high concentrations are discussed in the frame of a simple physical model where segments at the persistence length scale are treated as flexible rodlike segments.
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Affiliation(s)
- T Uematsu
- Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden.
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Johansson P, Edvardsson M, Adebahr J, Jacobsson P. Mixed Solvent and Polymer Coordination in PAN and PMMA Gel Polymer Electrolytes Studied by Ab Initio Calculations and Raman Spectroscopy. J Phys Chem B 2003. [DOI: 10.1021/jp035138t] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Patrik Johansson
- Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
| | - Magnus Edvardsson
- Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
| | - Josefina Adebahr
- Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
| | - Per Jacobsson
- Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
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Abstract
The electrochemical and physical-chemical properties of two families of lithium ion conducting membranes, i.e., the blends between high molecular weight poly(ethylene oxide) with a lithium salt commonly named "polymer electrolytes" and the gels of liquid solutions in a polymer matrix commonly named "gel electrolytes," are repoted and discussed. Particular attention is devoted to the newly developed approach of dispersing ceramic powders at the nanoscale particle dimension into the two types of membranes. This leads "nanocomposite" membranes having unique features, such as improved transport and interfacial properties in the case of the polymer electrolytes and enhanced liquid retention capability in the case of the gel electrolytes. Finally, the use of the gel electrolytes for the development of new-design, plastic-like, lithium-ion batteries is illustrated.
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Affiliation(s)
- B Scrosati
- Department of Chemistry, University La Sapienza, Rome, Italy.
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