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Bridges CR, Ford MJ, Thomas EM, Gomez C, Bazan GC, Segalman RA. Effects of Side Chain Branch Point on Self Assembly, Structure, and Electronic Properties of High Mobility Semiconducting Polymers. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b01906] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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52
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Segalman RA, Doherty MF. Introduction. Annu Rev Chem Biomol Eng 2018; 9:i. [DOI: 10.1146/annurev-ch-09-052418-100001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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53
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Ekerdt BL, Fuentes CM, Lei Y, Adil MM, Ramasubramanian A, Segalman RA, Schaffer DV. Thermoreversible Hyaluronic Acid-PNIPAAm Hydrogel Systems for 3D Stem Cell Culture. Adv Healthc Mater 2018; 7:e1800225. [PMID: 29717823 PMCID: PMC6289514 DOI: 10.1002/adhm.201800225] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 03/27/2018] [Indexed: 12/20/2022]
Abstract
Human pluripotent stem cells (hPSCs) offer considerable potential for biomedical applications including drug screening and cell replacement therapies. Clinical translation of hPSCs requires large quantities of high quality cells, so scalable methods for cell culture are needed. However, current methods are limited by scalability, the use of animal-derived components, and/or low expansion rates. A thermoresponsive 3D hydrogel for scalable hPSC expansion and differentiation into several defined lineages is recently reported. This system would benefit from increased control over material properties to further tune hPSC behavior, and here a scalable 3D biomaterial with the capacity to tune both the chemical and the mechanical properties is demonstrated to promote hPSC expansion under defined conditions. This 3D biomaterial, comprised of hyaluronic acid and poly(N-isopropolyacrylamide), has thermoresponsive properties that readily enable mixing with cells at low temperatures, physical encapsulation within the hydrogel upon elevation at 37 °C, and cell recovery upon cooling and reliquefaction. After optimization, the resulting biomaterial supports hPSC expansion over long cell culture periods while maintaining cell pluripotency. The capacity to modulate the mechanical and chemical properties of the hydrogel provides a new avenue to expand hPSCs for future therapeutic application.
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Davidson EC, Rosales AM, Patterson AL, Russ B, Yu B, Zuckermann RN, Segalman RA. Impact of Helical Chain Shape in Sequence-Defined Polymers on Polypeptoid Block Copolymer Self-Assembly. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b00055] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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55
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Sanoja GE, Schauser NS, Bartels JM, Evans CM, Helgeson ME, Seshadri R, Segalman RA. Ion Transport in Dynamic Polymer Networks Based on Metal–Ligand Coordination: Effect of Cross-Linker Concentration. Macromolecules 2018. [DOI: 10.1021/acs.macromol.7b02141] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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56
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Bartels J, Sanoja GE, Evans CM, Segalman RA, Helgeson ME. Decoupling Mechanical and Conductive Dynamics of Polymeric Ionic Liquids via a Trivalent Anion Additive. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b01351] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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57
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Davidson EC, Segalman RA. Thermal Control of Confined Crystallization within P3EHT Block Copolymer Microdomains. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b01616] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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58
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Davidson EC, Segalman RA. Confined Crystallization within Cylindrical P3EHT Block Copolymer Microdomains. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b01323] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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59
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Bridges CR, Ford MJ, Bazan GC, Segalman RA. Molecular Considerations for Mesophase Interaction and Alignment of Lyotropic Liquid Crystalline Semiconducting Polymers. ACS Macro Lett 2017; 6:619-624. [PMID: 35650847 DOI: 10.1021/acsmacrolett.7b00273] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Intermolecular interactions in conjugated polymers influence crystallinity, self-assembly, and packing motif, factors which in turn crucially impact charge transport properties such as carrier mobility in organic electronic devices. Correlated alignment of molecular and crystalline morphologies provides direct pathways for charge carriers to follow; however, the role of intermolecular interactions in achieving this is unexplored. Herein, we synthesize a series of lyotropic liquid crystalline conjugated polymers with variable side-chain structure to lend distinct steric repulsion and van der Waals attractive forces to each mesophase. We use this to investigate the role of intermolecular interactions on mesophase alignment. The strength of intermolecular interaction for each mesophase is compared by measuring melting temperature, π-stacking distance, and the Maier-Saupe interaction parameter. In general we find that side-chain structure can impact interaction strength by varying steric repulsion and backbone attractions and that the Maier-Saupe interaction parameters correlate with higher degrees of alignment after shearing, achieving a dichroic absorbance ratio of up to 2. This observation is used to develop equilibrium processing methods for fabricating macroscopically aligned polymer substrates used in transistors, improving mobility by a factor of 3 compared to spin-coated devices.
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Patterson AL, Wenning B, Rizis G, Calabrese DR, Finlay JA, Franco SC, Zuckermann RN, Clare AS, Kramer EJ, Ober CK, Segalman RA. Role of Backbone Chemistry and Monomer Sequence in Amphiphilic Oligopeptide- and Oligopeptoid-Functionalized PDMS- and PEO-Based Block Copolymers for Marine Antifouling and Fouling Release Coatings. Macromolecules 2017. [DOI: 10.1021/acs.macromol.6b02505] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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61
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Bridges CR, Ford MJ, Popere BC, Bazan GC, Segalman RA. Formation and Structure of Lyotropic Liquid Crystalline Mesophases in Donor–Acceptor Semiconducting Polymers. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01650] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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62
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Evans CM, Bridges CR, Sanoja GE, Bartels J, Segalman RA. Role of Tethered Ion Placement on Polymerized Ionic Liquid Structure and Conductivity: Pendant versus Backbone Charge Placement. ACS Macro Lett 2016; 5:925-930. [PMID: 35607206 DOI: 10.1021/acsmacrolett.6b00534] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The role of ion placement was systematically investigated in imidazolium bis(trifluoromethane)sulfonimide (ImTFSI) polymerized ionic liquids (PILs) containing pendant charges and charges in the backbone (sometimes called ionenes). The backbone PILs were synthesized via a facile step growth route, and pendant PILs were synthesized via RAFT. Both PILs were designed to have nearly identical charge density, and the conductivity was found to be substantially enhanced in the backbone PIL systems even after accounting for differences in the glass transition temperature (Tg). Wide-angle X-ray scattering (WAXS) revealed an invariance in the location of the amorphous halo between the two systems, while the anion-anion correlation peak was shifted to lower scattering wavevector (q) in the backbone PILs. This indicates an increase in the correlation length of ions and is consistent with charge transport along a more correlated pathway following the polymer backbone. Due to the linear nature of the backbone PILs, crystallization was observed and correlated with changes in conductivity. Upon crystallization, the conductivity dropped, and eventually, two populations of mobile ions were observed and attributed to ions in the amorphous and near-crystallite regions. The present work demonstrates the important role of ion placement on local structure and conductivity as well as the ability of backbone PILs to be used as controllable optical or dielectric materials based on crystallization or processing history.
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63
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Fang H, Popere BC, Thomas EM, Mai CK, Chang WB, Bazan GC, Chabinyc ML, Segalman RA. Large-scale integration of flexible materials into rolled and corrugated thermoelectric modules. J Appl Polym Sci 2016. [DOI: 10.1002/app.44208] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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64
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Mai CK, Liu J, Evans CM, Segalman RA, Chabinyc ML, Cahill DG, Bazan GC. Anisotropic Thermal Transport in Thermoelectric Composites of Conjugated Polyelectrolytes/Single-Walled Carbon Nanotubes. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b00546] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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65
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Chang WB, Fang H, Liu J, Evans CM, Russ B, Popere BC, Patel SN, Chabinyc ML, Segalman RA. Electrochemical Effects in Thermoelectric Polymers. ACS Macro Lett 2016; 5:455-459. [PMID: 35607236 DOI: 10.1021/acsmacrolett.6b00054] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Conductive polymers such as PEDOT:PSS hold great promise as flexible thermoelectric devices. The thermoelectric power factor of PEDOT:PSS is small relative to inorganic materials because the Seebeck coefficient is small. Ion conducting materials have previously been demonstrated to have very large Seebeck coefficients, and a major advantage of polymers over inorganics is the high room temperature ionic conductivity. Notably, PEDOT:PSS demonstrates a significant but short-term increase in Seebeck coefficient which is attributed to a large ionic Seebeck contribution. By controlling whether electrochemistry occurs at the PEDOT:PSS/electrode interface, the duration of the ionic Seebeck enhancement can be controlled, and a material can be designed with long-lived ionic Seebeck enhancements.
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Sanoja GE, Popere BC, Beckingham BS, Evans CM, Lynd NA, Segalman RA. Structure–Conductivity Relationships of Block Copolymer Membranes Based on Hydrated Protic Polymerized Ionic Liquids: Effect of Domain Spacing. Macromolecules 2016. [DOI: 10.1021/acs.macromol.5b02614] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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67
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Chang WB, Evans CM, Popere BC, Russ BM, Liu J, Newman J, Segalman RA. Harvesting Waste Heat in Unipolar Ion Conducting Polymers. ACS Macro Lett 2016; 5:94-98. [PMID: 35668585 DOI: 10.1021/acsmacrolett.5b00829] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The Seebeck effect in unipolar ion-conducting, solid-state polymers is characterized. The high Seebeck coefficient and sign in polymer ion conductors is explained via analysis of thermogalvanic multicomponent transport. A solid-state, water-processeable, flexible device based on these materials is demonstrated, showcasing the promise of polymers as thermogalvanic materials. Thermogalvanic materials based on ion-conducting polymer membranes show great promise in the harvesting of waste heat.
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68
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Evans CM, Sanoja GE, Popere BC, Segalman RA. Anhydrous Proton Transport in Polymerized Ionic Liquid Block Copolymers: Roles of Block Length, Ionic Content, and Confinement. Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b02202] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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69
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Russ B, Robb MJ, Popere BC, Perry EE, Mai CK, Fronk SL, Patel SN, Mates TE, Bazan GC, Urban JJ, Chabinyc ML, Hawker CJ, Segalman RA. Tethered tertiary amines as solid-state n-type dopants for solution-processable organic semiconductors. Chem Sci 2015; 7:1914-1919. [PMID: 29899915 PMCID: PMC5966797 DOI: 10.1039/c5sc04217h] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 12/06/2015] [Indexed: 12/26/2022] Open
Abstract
Tertiary amines covalently tethered to electron-deficient aromatic molecules by alkyl spacers enable solid-state n-doping.
A scarcity of stable n-type doping strategies compatible with facile processing has been a major impediment to the advancement of organic electronic devices. Localizing dopants near the cores of conductive molecules can lead to improved efficacy of doping. We and others recently showed the effectiveness of tethering dopants covalently to an electron-deficient aromatic molecule using trimethylammonium functionalization with hydroxide counterions linked to a perylene diimide core by alkyl spacers. In this work, we demonstrate that, contrary to previous hypotheses, the main driver responsible for the highly effective doping observed in thin films is the formation of tethered tertiary amine moieties during thin film processing. Furthermore, we demonstrate that tethered tertiary amine groups are powerful and general n-doping motifs for the successful generation of free electron carriers in the solid-state, not only when coupled to the perylene diimide molecular core, but also when linked with other small molecule systems including naphthalene diimide, diketopyrrolopyrrole, and fullerene derivatives. Our findings help expand a promising molecular design strategy for future enhancements of n-type organic electronic materials.
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70
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Davidson EC, Beckingham BS, Ho V, Segalman RA. Confined crystallization in lamellae forming poly(3-(2′-ethyl)hexylthiophene) (P3EHT) block copolymers. ACTA ACUST UNITED AC 2015. [DOI: 10.1002/polb.23904] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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71
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Leng C, Buss HG, Segalman RA, Chen Z. Surface Structure and Hydration of Sequence-Specific Amphiphilic Polypeptoids for Antifouling/Fouling Release Applications. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:9306-11. [PMID: 26245923 DOI: 10.1021/acs.langmuir.5b01440] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Amphiphilic polypeptoids can be designed with specific sequences of hydrophilic and hydrophobic units, which determine their surface properties for antifouling/fouling release purposes. Although the sequence-dependent surface structures of polypeptoids have been extensively investigated, e.g., with X-ray spectroscopy, their molecular structures under the aqueous conditions relevant to marine fouling have not been studied. In this work, we applied sum frequency generation (SFG) vibrational spectroscopy to study the surface structures and hydration of a series of amphiphilic polypeptoid coatings with different sequences in air and water. SFG spectra, in agreement with X-ray spectroscopy studies, revealed that the surface coverage of the hydrophilic N-(2-methoxyethyl)glycine (Nme) units in air is affected by both the number and position of the hydrophobic N-(heptafluorobutyl)glycine (NF) units in the peptoid chain and is negatively correlated with the surface concentration of the fluorine element. Our ability to probe the SFG signals of water molecules at the peptoid surface provides new information on the hydrated film properties. From these SFG signals and the time evolution of water contact angles on the polymers, we see that the hydrated film properties are also dependent upon the peptoid sequence. This work indicates that the surface presence of the Nme groups and the ability of the polymers to order and strongly hydrogen bond with interfacial water molecules determine their antifouling properties, whereas the surface restructuring rate upon contact with water affects their fouling release behaviors.
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72
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Evans CM, Singh MR, Lynd NA, Segalman RA. Improving the Gas Barrier Properties of Nafion via Thermal Annealing: Evidence for Diffusion through Hydrophilic Channels and Matrix. Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b00579] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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73
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Liu J, Wang X, Li D, Coates NE, Segalman RA, Cahill DG. Thermal Conductivity and Elastic Constants of PEDOT:PSS with High Electrical Conductivity. Macromolecules 2015. [DOI: 10.1021/ma502099t] [Citation(s) in RCA: 216] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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74
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Cho ES, Evans CM, Davidson EC, Hoarfrost ML, Modestino MA, Segalman RA, Urban JJ. Enhanced Water Vapor Blocking in Transparent Hybrid Polymer-Nanocrystal Films. ACS Macro Lett 2015; 4:70-74. [PMID: 35596375 DOI: 10.1021/mz500765y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Highly transparent and effective encapsulating materials have become increasingly important for photovoltaic (PV) modules to prevent water vapor molecules from permeating PV cells. The composite consists of block copolymer (PS-b-P2VP), comprised of hydrophobic and hydrophilic parts, and hygroscopic nanocrystals (Magnesium Oxide, MgO) incorporated to enhance water vapor blocking by both presenting obstacles for mass transport and also scavenging water molecules. The water vapor transmission rate (WVTR) values were reduced ∼3000 times, compared to homopolymer (PS), for both polymer and composite samples. Achieving both high transparency and low WVTR, it is expected that the composite materials can function as an excellent water vapor blocking layer for PV modules.
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75
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Mai CK, Arai T, Liu X, Fronk SL, Su GM, Segalman RA, Chabinyc ML, Bazan GC. Electrical properties of doped conjugated polyelectrolytes with modulated density of the ionic functionalities. Chem Commun (Camb) 2015; 51:17607-10. [DOI: 10.1039/c5cc06690e] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We report the synthesis of a series of water soluble anionic narrow band-gap conjugated polyelectrolytes with a varied density of the ionic functional groups.
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