1
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Coote J, Adotey SKJ, Sangoro JR, Stein GE. Interfacial Effects in Conductivity Measurements of Block Copolymer Electrolytes. ACS POLYMERS AU 2023; 3:331-343. [PMID: 37576709 PMCID: PMC10416321 DOI: 10.1021/acspolymersau.2c00068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 03/23/2023] [Accepted: 03/24/2023] [Indexed: 04/08/2023]
Abstract
The ionic conductivity in lamellar block copolymer electrolytes is often anisotropic, where the in-plane conductivity exceeds the through-plane conductivity by up to an order of magnitude. In a prior work, we showed significant anisotropy in the ionic conductivity of a lamellar block copolymer based on polystyrene (PS) and a polymer ionic liquid (PIL), and we proposed that the through-film ionic conductivity was depressed by layering of lamellar domains near the electrode surface. In the present work, we first tested that conclusion by measuring the through-plane ionic conductivity of two model PIL-based systems having controlled interfacial profiles using impedance spectroscopy. The measurements were not sensitive to changes in interfacial composition or structure, so anisotropy in the ionic conductivity of PS-block-PIL materials must arise from an in-plane enhancement rather than a through-plane depression. We then examined the origin of this in-plane enhancement with a series of PS-block-PIL materials, a P(S-r-IL) copolymer, and a PIL homopolymer, where impedance spectra were acquired with a top-contact electrode configuration. These studies show that enhanced in-plane ionic conductivities are correlated with the formation of an IL-rich wetting layer at the free surface, which presumably provides a low-resistance path for ion transport between the electrodes. Importantly, the enhanced in-plane ionic conductivities in these PS-block-PIL materials are consistent with simple geometric arguments based on properties of the PIL, while the through-plane values are an order of magnitude lower. Consequently, it is critical to understand how surface and bulk effects contribute to impedance spectroscopy measurements when developing structure-conductivity relations in this class of materials.
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Affiliation(s)
- Jonathan
P. Coote
- Department
of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Samuel K. J. Adotey
- Department
of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Joshua R. Sangoro
- Department
of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
| | - Gila E. Stein
- Department
of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
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2
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Lee J, Gao KW, Shah NJ, Kang C, Snyder RL, Abel BA, He L, Teixeira SCM, Coates GW, Balsara NP. Relationship between Ion Transport and Phase Behavior in Acetal-Based Polymer Blend Electrolytes Studied by Electrochemical Characterization and Neutron Scattering. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c01724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Jaeyong Lee
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, California94720, United States
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California94720, United States
- Joint Center for Energy Storage Research (JCESR), Argonne National Laboratory, Lemont, Illinois60439, United States
| | - Kevin W. Gao
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, California94720, United States
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California94720, United States
- Joint Center for Energy Storage Research (JCESR), Argonne National Laboratory, Lemont, Illinois60439, United States
| | - Neel J. Shah
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, California94720, United States
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California94720, United States
| | - Cheol Kang
- Joint Center for Energy Storage Research (JCESR), Argonne National Laboratory, Lemont, Illinois60439, United States
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York14850, United States
| | - Rachel L. Snyder
- Joint Center for Energy Storage Research (JCESR), Argonne National Laboratory, Lemont, Illinois60439, United States
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York14850, United States
| | - Brooks A. Abel
- Department of Chemistry, University of California, Berkeley, Berkeley, California94720, United States
| | - Lilin He
- Neutron Scattering Division, Oak Ridge National Laboratory, Knoxville, Tennessee37830, United States
| | - Susana C. M. Teixeira
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland20899, United States
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware19716, United States
| | - Geoffrey W. Coates
- Joint Center for Energy Storage Research (JCESR), Argonne National Laboratory, Lemont, Illinois60439, United States
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York14850, United States
| | - Nitash P. Balsara
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, California94720, United States
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California94720, United States
- Joint Center for Energy Storage Research (JCESR), Argonne National Laboratory, Lemont, Illinois60439, United States
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3
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Charge Transport and Glassy Dynamics in Blends Based on 1-Butyl-3-vinylbenzylimidazolium Bis(trifluoromethanesulfonyl)imide Ionic Liquid and the Corresponding Polymer. Polymers (Basel) 2022; 14:polym14122423. [PMID: 35745999 PMCID: PMC9227190 DOI: 10.3390/polym14122423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 06/03/2022] [Accepted: 06/13/2022] [Indexed: 11/16/2022] Open
Abstract
Charge transport, diffusion properties, and glassy dynamics of blends of imidazolium-based ionic liquid (IL) and the corresponding polymer (polyIL) were examined by Pulsed-Field-Gradient Nuclear Magnetic Resonance (PFG-NMR) and rheology coupled with broadband dielectric spectroscopy (rheo-BDS). We found that the mechanical storage modulus (G′) increases with an increasing amount of polyIL and G′ is a factor of 10,000 higher for the polyIL compared to the monomer (GIL′= 7.5 Pa at 100 rad s−1 and 298 K). Furthermore, the ionic conductivity (σ0) of the IL is a factor 1000 higher than its value for the polymerized monomer with 3.4×10−4 S cm−1 at 298 K. Additionally, we found the Haven Ratio (HR) obtained through PFG-NMR and BDS measurements to be constant around a value of 1.4 for the IL and blends with 30 wt% and 70 wt% polyIL. These results show that blending of the components does not have a strong impact on the charge transport compared to the charge transport in the pure IL at room temperature, but blending results in substantial modifications of the mechanical properties. Furthermore, it is highlighted that the increase in σ0 might be attributed to the addition of a more mobile phase, which also possibly reduces ion-ion correlations in the polyIL.
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Xu H, Mahanthappa MK. Ionic Conductivities of Broad Dispersity Lithium Salt-Doped Polystyrene/Poly(ethylene oxide) Triblock Polymers. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c01100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hongyun Xu
- Department of Chemical Engineering & Materials Science, University of Minnesota, 421 Washington Avenue Southeast, Minneapolis, Minnesota 55455, United States
| | - Mahesh K. Mahanthappa
- Department of Chemical Engineering & Materials Science, University of Minnesota, 421 Washington Avenue Southeast, Minneapolis, Minnesota 55455, United States
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5
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Lee C, Osuji CO. 100th Anniversary of Macromolecular Science Viewpoint: Opportunities for Liquid Crystal Polymers in Nanopatterning and Beyond. ACS Macro Lett 2021; 10:945-957. [PMID: 35549196 DOI: 10.1021/acsmacrolett.1c00350] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Liquid-crystal polymers (LCPs) integrate at a molecular level the characteristics of two important material classes, i.e., liquid crystals (LCs) and polymers. As a result, they exhibit a wide variety of intriguing physical phenomena and have useful properties in various settings. In the nearly 50 years since the discovery of the first melt-processable LCPs, there has been a remarkable expansion in the field encompassing the development of new chain architectures, the incorporation of new classes of mesogens, and the exploration of new properties and applications. As engineering materials, LCPs are historically best known in the context of high strength fibers. In a more contemporary study, the pairing of LC mesophase assembly with block copolymer (BCP) self-assembly in LC BCPs has resulted in a fascinating interplay of ordering phenomena and rich phase behavior, while lightly cross-linked networks, LC elastomers, are extensively investigated as shape memory materials based on their thermomechanical actuation. As this Viewpoint describes, these and other examples are active areas of research in which new, compelling opportunities for LCPs are emerging. We highlight a few selected areas that we view as being potentially significant in the near future, with a particular emphasis on nanopatterning. Here, the ability to readily access small feature sizes, the fluidity of the LC mesophase, and LC-based handles for achieving orientation control present a compelling combination. Opportunities for LCPs are also presented under the broad rubric of "beyond nanopatterning", and we discuss relevant challenges and potential new directions in the field.
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Affiliation(s)
- Changyeon Lee
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Chinedum O. Osuji
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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6
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Modification of the Properties of Polymer Composites in a Constant Magnetic Field Environment. MATERIALS 2021; 14:ma14143806. [PMID: 34300725 PMCID: PMC8303739 DOI: 10.3390/ma14143806] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/30/2021] [Accepted: 07/01/2021] [Indexed: 11/17/2022]
Abstract
In this paper, polymer composites based on polylactide (PLA) and epoxy resin (Epidian 5) were studied in terms of the influence of magnetic induction on their changes in physicochemical properties. The composites contained admixtures in the form of magnetite (Fe3O4) and crystalline cellulose (Avicel PH-1010) in the amount of 10%, 20%, and 30% by weight and starch in the amount of 10%. The admixtures of cellulose and starch were intended to result in the composites becoming biodegradable biopolymers to some extent. Changes in physical and chemical properties due to the impact of a constant magnetic field with a magnetic induction value B = 0.5 T were observed. The changes were observed during tests of tensile strength, bending, impact strength, water absorbency, frost resistance, chemical resistance to acids and bases, as well as through SEM microscopy and with studies of the composition of the composites that use the EDS method and of their structure with the XRD method. Based on the obtained results, it was found that the magnetic induction value changes the properties of composites. This therefore acts as one method of receiving new alternative materials, the degradation of which in the environment would take far less time.
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7
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Tu TH, Sakurai T, Seki S, Ishida Y, Chan YT. Towards Macroscopically Anisotropic Functionality: Oriented Metallo-supramolecular Polymeric Materials Induced by Magnetic Fields. Angew Chem Int Ed Engl 2021; 60:1923-1928. [PMID: 33051951 DOI: 10.1002/anie.202012284] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Indexed: 12/18/2022]
Abstract
Based on the predesigned self-selective complexation, metallo-supramolecular P3HT-b-PEO diblock copolymers with varying block ratios were synthesized, and their oriented polymer films generated during solvent evaporation in a 9 T magnetic field were investigated. An anisotropic, ordered layer structure was achieved using [P3HT20 -Zn-PEO107 ] and carefully characterized by polarized optical microscopy (POM), AFM, polarized UV/Vis spectroscopy, and GI-SAXS/WAXS. The PEO-removed [P3HT20 -Zn-PEO107 ] film was obtained after decomplexation with TEA-EDTA under mild conditions, and the selective removal of PEO domains was evidenced by UV/Vis and ATR-FTIR spectroscopy. Anisotropic photoconductivity of the magnetically aligned film was evaluated by flash-photolysis time-resolved microwave conductivity (FP-TRMC) measurements. The results indicated that the presence of insulating crystalline PEO segments diminished the photoconductivity along the P3HT backbone direction.
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Affiliation(s)
- Tsung-Han Tu
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan
| | - Tsuneaki Sakurai
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan
| | - Shu Seki
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan
| | - Yasuhiro Ishida
- RIKEN Center for Emergent Matter Science, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Yi-Tsu Chan
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan
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8
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Tu T, Sakurai T, Seki S, Ishida Y, Chan Y. Towards Macroscopically Anisotropic Functionality: Oriented Metallo‐supramolecular Polymeric Materials Induced by Magnetic Fields. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202012284] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Tsung‐Han Tu
- Department of Chemistry National Taiwan University Taipei 10617 Taiwan
| | - Tsuneaki Sakurai
- Department of Molecular Engineering Graduate School of Engineering Kyoto University, Nishikyo-ku Kyoto 615-8510 Japan
| | - Shu Seki
- Department of Molecular Engineering Graduate School of Engineering Kyoto University, Nishikyo-ku Kyoto 615-8510 Japan
| | - Yasuhiro Ishida
- RIKEN Center for Emergent Matter Science 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Yi‐Tsu Chan
- Department of Chemistry National Taiwan University Taipei 10617 Taiwan
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9
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Leniart A, Pula P, Sitkiewicz A, Majewski PW. Macroscopic Alignment of Block Copolymers on Silicon Substrates by Laser Annealing. ACS NANO 2020; 14:4805-4815. [PMID: 32159943 PMCID: PMC7497666 DOI: 10.1021/acsnano.0c00696] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 03/11/2020] [Indexed: 05/07/2023]
Abstract
Laser annealing is a competitive alternative to conventional oven annealing of block copolymer (BCP) thin films enabling rapid acceleration and precise spatial control of the self-assembly process. Localized heating by a moving laser beam (zone annealing), taking advantage of steep temperature gradients, can additionally yield aligned morphologies. In its original implementation it was limited to specialized germanium-coated glass substrates, which absorb visible light and exhibit low-enough thermal conductivity to facilitate heating at relatively low irradiation power density. Here, we demonstrate a recent advance in laser zone annealing, which utilizes a powerful fiber-coupled near-IR laser source allowing rapid BCP annealing over a large area on conventional silicon wafers. The annealing coupled with photothermal shearing yields macroscopically aligned BCP films, which are used as templates for patterning metallic nanowires. We also report a facile method of transferring laser-annealed BCP films onto arbitrary surfaces. The transfer process allows patterning substrates with a highly corrugated surface and single-step rapid fabrication of multilayered nanomaterials with complex morphologies.
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Affiliation(s)
| | - Przemyslaw Pula
- Department
of Chemistry, University of Warsaw, Warsaw, 02089, Poland
| | | | - Pawel W. Majewski
- Department
of Chemistry, University of Warsaw, Warsaw, 02089, Poland
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10
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Coote JP, Kinsey T, Street DP, Kilbey SM, Sangoro JR, Stein GE. Surface-Induced Ordering Depresses Through-Film Ionic Conductivity in Lamellar Block Copolymer Electrolytes. ACS Macro Lett 2020; 9:565-570. [PMID: 35648487 DOI: 10.1021/acsmacrolett.0c00039] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Lamellar block copolymers based on polymeric ionic liquids (PILs) show promise as electrolytes in electrochemical devices. However, these systems often display structural anisotropy that depresses the through-film ionic conductivity. This work hypothesizes that structural anisotropy is a consequence of surface-induced ordering, where preferential adsorption of one block at the electrode drives a short-range stacking of the lamellae. This point was examined with lamellar diblock copolymers of polystyrene (PS) and poly(1-(2-acryloyloxyethyl)-3-butylimidazolium bis(trifluoromethanesulfonyl)imide) (PIL). The bulk PS-PIL structure was comprised of randomly oriented lamellar grains. However, in thin PS-PIL films (100-400 nm), the lamellae were stacked normal to the plane of the film, and islands/holes were observed when the as-prepared film thickness was incommensurate with the natural lamellar periodicity. Both of these attributes are well-known consequences of preferential wetting at surfaces. The ionic conductivity of thick PS-PIL films (50-100 μm) was approximately 20× higher in the in-plane direction than in the through-plane direction, consistent with a mixed structure comprised of randomly oriented lamellae throughout the interior of the film and highly oriented lamellae at the electrode surface. Therefore, to fully optimize the performance of a block copolymer electrolyte, it is important to consider the effects of surface interactions on the ordering of domains.
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11
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Galluzzo MD, Loo WS, Wang AA, Walton A, Maslyn JA, Balsara NP. Measurement of Three Transport Coefficients and the Thermodynamic Factor in Block Copolymer Electrolytes with Different Morphologies. J Phys Chem B 2020; 124:921-935. [DOI: 10.1021/acs.jpcb.9b11066] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Michael D. Galluzzo
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Whitney S. Loo
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Andrew A. Wang
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Amber Walton
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Jacqueline A. Maslyn
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Nitash P. Balsara
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Joint Center for Energy Storage Research (JCESR), Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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12
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Characterisation of the PS-PMMA Interfaces in Microphase Separated Block Copolymer Thin Films by Analytical (S)TEM. NANOMATERIALS 2020; 10:nano10010141. [PMID: 31941037 PMCID: PMC7022429 DOI: 10.3390/nano10010141] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 01/08/2020] [Accepted: 01/09/2020] [Indexed: 11/16/2022]
Abstract
Block copolymer (BCP) self-assembly is a promising tool for next generation lithography as microphase separated polymer domains in thin films can act as templates for surface nanopatterning with sub-20 nm features. The replicated patterns can, however, only be as precise as their templates. Thus, the investigation of the morphology of polymer domains is of great importance. Commonly used analytical techniques (neutron scattering, scanning force microscopy) either lack spatial information or nanoscale resolution. Using advanced analytical (scanning) transmission electron microscopy ((S)TEM), we provide real space information on polymer domain morphology and interfaces between polystyrene (PS) and polymethylmethacrylate (PMMA) in cylinder- and lamellae-forming BCPs at highest resolution. This allows us to correlate the internal structure of polymer domains with line edge roughnesses, interface widths and domain sizes. STEM is employed for high-resolution imaging, electron energy loss spectroscopy and energy filtered TEM (EFTEM) spectroscopic imaging for material identification and EFTEM thickness mapping for visualisation of material densities at defects. The volume fraction of non-phase separated polymer species can be analysed by EFTEM. These methods give new insights into the morphology of polymer domains the exact knowledge of which will allow to improve pattern quality for nanolithography.
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13
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Ndaya D, Bosire R, Vaidya S, Kasi RM. Molecular engineering of stimuli-responsive, functional, side-chain liquid crystalline copolymers: synthesis, properties and applications. Polym Chem 2020. [DOI: 10.1039/d0py00749h] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This review describes recent progress made in designing stimuli-responsive, functional, side-chain, end-on mesogen attached liquid crystalline polymers (LCPs).
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Affiliation(s)
- Dennis Ndaya
- Department of Chemistry
- University of Connecticut
- Storrs
- USA
| | - Reuben Bosire
- Department of Chemistry
- University of Connecticut
- Storrs
- USA
| | | | - Rajeswari M. Kasi
- Department of Chemistry
- University of Connecticut
- Storrs
- USA
- Polymer Program
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14
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Kambe Y, Arges CG, Czaplewski DA, Dolejsi M, Krishnan S, Stoykovich MP, de Pablo JJ, Nealey PF. Role of Defects in Ion Transport in Block Copolymer Electrolytes. NANO LETTERS 2019; 19:4684-4691. [PMID: 31250653 DOI: 10.1021/acs.nanolett.9b01758] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Ion conducting block copolymers can overcome traditional limitations of homopolymer electrolytes by phase separating into nanoarchitectures that can be simultaneously optimized for two or more orthogonal material properties such as high ionic conductivity and mechanical stability. A key challenge in understanding the ion transport properties of these materials is the difficulty of extracting structure-function relationships without having complete knowledge of all nanoscale transport pathways in bulk samples. Here we demonstrate a method for deriving structure-transport relationships for ion conducting block copolymers using thin films and interdigitated electrodes. Well-defined and directly imaged structure in films of poly(styrene)-block-poly(2-vinylpyridine) is controlled using techniques of directed self-assembly then the poly(2-vinylpyridine) is selectively converted into an ion conductor. The ion conductivity is found to be directly proportional to the total number of connected paths between electrodes and the path length. A single defect such as a dislocation anywhere in the path of an ion conducting route disconnects and precludes that pathway from contributing to the conductivity and results in an increase in the dielectric parameter of the film. When all the ion conduction pathways are blocked between electrodes, the conductivity is negligible, 4 orders of magnitude lower compared to a completely connected morphology and the dielectric parameter increases by a factor of 50. These results have profound implications for the interpretation, design, and processing of block copolymer electrolytes for applications as ion conducting membranes.
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Affiliation(s)
- Yu Kambe
- Pritzker School of Molecular Engineering , University of Chicago , 5640 S. Ellis Avenue , Chicago , Illinois 60637 , United States
- Center for Molecular Engineering, Materials Science Division , Argonne National Laboratory , 9700 S. Cass Ave nue, Lemont , Illinois 60439 , United States
| | - Christopher G Arges
- Cain Department of Chemical Engineering , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
| | - David A Czaplewski
- Center for Nanoscale Materials , Argonne National Laboratory , 9700 S. Cass Avenue , Lemont , Illinois 60439 , United States
| | - Moshe Dolejsi
- Pritzker School of Molecular Engineering , University of Chicago , 5640 S. Ellis Avenue , Chicago , Illinois 60637 , United States
- Center for Molecular Engineering, Materials Science Division , Argonne National Laboratory , 9700 S. Cass Ave nue, Lemont , Illinois 60439 , United States
| | - Satya Krishnan
- Pritzker School of Molecular Engineering , University of Chicago , 5640 S. Ellis Avenue , Chicago , Illinois 60637 , United States
| | - Mark P Stoykovich
- Pritzker School of Molecular Engineering , University of Chicago , 5640 S. Ellis Avenue , Chicago , Illinois 60637 , United States
| | - Juan J de Pablo
- Pritzker School of Molecular Engineering , University of Chicago , 5640 S. Ellis Avenue , Chicago , Illinois 60637 , United States
- Center for Molecular Engineering, Materials Science Division , Argonne National Laboratory , 9700 S. Cass Ave nue, Lemont , Illinois 60439 , United States
| | - Paul F Nealey
- Pritzker School of Molecular Engineering , University of Chicago , 5640 S. Ellis Avenue , Chicago , Illinois 60637 , United States
- Center for Molecular Engineering, Materials Science Division , Argonne National Laboratory , 9700 S. Cass Ave nue, Lemont , Illinois 60439 , United States
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