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Robles-Hernández B, González-Burgos M, Malo de Molina P, Asenjo-Sanz I, Radulescu A, Pomposo JA, Arbe A, Colmenero J. Structure of Single-Chain Nanoparticles under Crowding Conditions: A Random Phase Approximation Approach. Macromolecules 2023; 56:8971-8979. [PMID: 38024156 PMCID: PMC10654932 DOI: 10.1021/acs.macromol.3c01333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 10/13/2023] [Accepted: 10/16/2023] [Indexed: 12/01/2023]
Abstract
The conformation of poly(methyl methacrylate) (PMMA)-based single-chain nanoparticles (SCNPs) and their corresponding linear precursors in the presence of deuterated linear PMMA in deuterated dimethylformamide (DMF) solutions has been studied by small-angle neutron scattering (SANS). The SANS profiles were analyzed in terms of a three-component random phase approximation (RPA) model. The RPA approach described well the scattering profiles in dilute and crowded solutions. Considering all the contributions of the RPA leads to an accurate estimation of the single chain form factor parameters and the Flory-Huggins interaction parameter between PMMA and DMF. The value of the latter in the dilute regime indicates that the precursors and the SCNPs are in good solvent conditions, while in crowding conditions, the polymer becomes less soluble.
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Affiliation(s)
| | - Marina González-Burgos
- Centro
de Física de Materiales/Materials Physics Center (CFM/MPC), 20018 Donostia-San
Sebastián, Spain
| | - Paula Malo de Molina
- Centro
de Física de Materiales/Materials Physics Center (CFM/MPC), 20018 Donostia-San
Sebastián, Spain
- IKERBASQUE—Basque
Foundation for Science, 48009 Bilbao, Spain
| | - Isabel Asenjo-Sanz
- Centro
de Física de Materiales/Materials Physics Center (CFM/MPC), 20018 Donostia-San
Sebastián, Spain
| | - Aurel Radulescu
- Jülich
Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum
(MLZ), Forschungszentrum Jülich GmbH, 85748 Garching, Germany
| | - José A. Pomposo
- Centro
de Física de Materiales/Materials Physics Center (CFM/MPC), 20018 Donostia-San
Sebastián, Spain
- IKERBASQUE—Basque
Foundation for Science, 48009 Bilbao, Spain
- Department
of Polymers and Advanced Materials: Physics, Chemistry and Technology, University of the Basque Country UPV/EHU, 20018 Donostia-San
Sebastián, Spain
| | - Arantxa Arbe
- Centro
de Física de Materiales/Materials Physics Center (CFM/MPC), 20018 Donostia-San
Sebastián, Spain
| | - Juan Colmenero
- Donostia
International Physics Center (DIPC), 20018 Donostia-San Sebastián, Spain
- Centro
de Física de Materiales/Materials Physics Center (CFM/MPC), 20018 Donostia-San
Sebastián, Spain
- Department
of Polymers and Advanced Materials: Physics, Chemistry and Technology, University of the Basque Country UPV/EHU, 20018 Donostia-San
Sebastián, Spain
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Sebastián N, Zupančič B, Zalar B, López DO, Salud J, de Rioja VL, Levit R, Robles-Hernández B, de la Fuente MR, Gimeno N, Ros MB, Diez-Berart S. DNMR measurements of an asymmetric odd liquid crystal dimer: determination of the intramolecular angle and the degree of order of the two rigid cores. Phys Chem Chem Phys 2023; 25:2486-2497. [PMID: 36602075 DOI: 10.1039/d2cp02696a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In this work, we present a Deuteron Nuclear Magnetic Resonance (DNMR) study of the non-symmetric odd liquid crystal dimer α-(4-cyanobiphenyl-4'-yloxy)-ω-(1-pyrenimine-benzylidene-4'-oxy) heptane (CBO7O.Py), formed by a pro-mesogenic cyanobiphenyl unit and a bulky pyrene-containing unit, linked via alkoxy flexible chain. We have synthesized two partially deuterated samples: one with the deuterium atoms in the cyanobiphenyl moiety (dCBO7O.Py) and the other one with the deuterium atoms in the pyrenimine-benzylidene unit (CBO7O.dPy). We have performed angular distribution analysis in the SmA glassy state, obtaining the degree of order of both rigid cores and an estimation of the internal molecular angle between both structures. With the results from the angular study, we have been able to determine the degree of order of both rigid units in either the N phase and the SmA phase, far enough from the glass transition. Both rigid cores have the same degree of order close to the nematic-isotropic phase transition, but as the compound is cooled down, the degree of order of the cyanobiphenyl moiety is clearly higher than that of the pyrene-containing unit. The critical behaviour of the order parameter of the pyrene-containing moiety is consistent with the fact that, for CBO7O.Py, the N-I phase transition is tricritical, which seems to indicate that the uniaxial order parameter of the dimer is dominated by the degree of order of the pyrene-containing core.
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Affiliation(s)
- Nerea Sebastián
- Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana, Slovenia.
| | - Blaz Zupančič
- Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana, Slovenia.
| | - Boštjan Zalar
- Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana, Slovenia.
| | - David O López
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, 08028 Barcelona, Spain
| | - Josep Salud
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, 08028 Barcelona, Spain
| | - Victor López de Rioja
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, 08028 Barcelona, Spain
| | - Rafael Levit
- Caracterització Elèctrica de Materials i Dispositius (CEMAD), Departament de Física, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, 08028 Barcelona, Spain
| | - Beatriz Robles-Hernández
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco (UPV-EHU), Apartado 644, E-48080 Bilbao, Spain.,Donostia International Physics Center, Manuel de Lardizabal Ibilbidea 4, 20018 Donostia, Spain
| | - María Rosario de la Fuente
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco (UPV-EHU), Apartado 644, E-48080 Bilbao, Spain
| | - Nélida Gimeno
- Donostia International Physics Center, Manuel de Lardizabal Ibilbidea 4, 20018 Donostia, Spain
| | - María Blanca Ros
- Instituto de Nanociencia de Materiales de Aragón (INMA), Departamento de Química Orgánica-Facultad de Ciencias, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
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Sellarès J, Diego JA, López DO, Salud J, Robles-Hernández B, de la Fuente MR, Cañadas JC, Mudarra M, López de Rioja V, Levit R, Diez-Berart S. Comparative dielectric and thermally stimulated-depolarization-current studies of the liquid crystal dimers 1″,9″-bis(4-cyanobiphenyl-4'-yl) nonane and heptane and a binary mixture between them, close to the glass transition. Phys Rev E 2022; 106:054702. [PMID: 36559473 DOI: 10.1103/physreve.106.054702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 10/27/2022] [Indexed: 06/17/2023]
Abstract
We have performed dielectric spectroscopy and thermally stimulated-depolarization-current experiments to study the molecular dynamics of the twist-bend nematic phase close to the glass transition of two members of the 1″,7'-bis(4-cyanobiphenyl-4'-yl)alkane homologous series (CBnCB): the liquid crystal (LC) dimers CB9CB and CB7CB, as well as a binary mixture of both. By doping CB9CB with a small quantity of CB7CB, the crystallization is inhibited when cooling the sample down, while the bulk properties of CB9CB are retained and we can investigate the supercooled behavior close to the glass transition. The study reveals that the inter- and intramolecular interactions of the mixture are similar to those of pure CB9CB and confirms that there is a single glass transition in symmetric LC dimers.
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Affiliation(s)
- Jordi Sellarès
- DILAB, Departament de Física, E.S.E.I.A.A.T. Universitat Politècnica de Catalunya, Colom 11, 08222 Terrassa, Spain
| | - José Antonio Diego
- DILAB, Departament de Física, E.S.E.I.A.A.T. Universitat Politècnica de Catalunya, Colom 11, 08222 Terrassa, Spain
| | - David O López
- Grup de les Propietas Físiques del Materials (GRPFM), Departament de Física, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Avinguda Diagonal, 647, 08028 Barcelona, Spain
| | - Josep Salud
- Grup de les Propietas Físiques del Materials (GRPFM), Departament de Física, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Avinguda Diagonal, 647, 08028 Barcelona, Spain
| | - Beatriz Robles-Hernández
- Donostia International Physics Center, Manuel Lardizabal Ibilbidea 4, 20018 Donostia, Spain
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apartado 644, E-48080 Bilbao, Spain
| | - María Rosario de la Fuente
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apartado 644, E-48080 Bilbao, Spain
| | - Juan Carlos Cañadas
- DILAB, Departament de Física, E.S.E.I.A.A.T. Universitat Politècnica de Catalunya, Colom 11, 08222 Terrassa, Spain
| | - Miguel Mudarra
- DILAB, Departament de Física, E.S.E.I.A.A.T. Universitat Politècnica de Catalunya, Colom 11, 08222 Terrassa, Spain
| | - Victor López de Rioja
- Grup de les Propietas Físiques del Materials (GRPFM), Departament de Física, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Avinguda Diagonal, 647, 08028 Barcelona, Spain
| | - Rafael Levit
- Caracterització Elèctrica dels Materials i Dispositius (CEMAD), Departament de Física, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Avinguda Diagonal, 647, 08028 Barcelona, Spain
| | - Sergio Diez-Berart
- Grup de les Propietas Físiques del Materials (GRPFM), Departament de Física, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Avinguda Diagonal, 647, 08028 Barcelona, Spain
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Martínez-Tong DE, Soccio M, Robles-Hernández B, Guidotti G, Gazzano M, Lotti N, Alegria A. Evidence of Nanostructure Development from the Molecular Dynamics of Poly(pentamethylene 2,5-furanoate). Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c02297] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Daniel E. Martínez-Tong
- Departamento de Polímeros y Materiales Avanzados: Física, Química y Tecnología, University of the Basque Country (UPV/EHU). Paseo Manuel Lardizábal 3, 20018 Donostia, Spain
- Centro de Física de Materiales (CFM, CSIC-UPV/EHU), Paseo Manuel Lardizábal 5, 20018 Donostia, Spain
| | - Michelina Soccio
- Civil, Chemical, Environmental and Materials Engineering Department, University of Bologna, Via Terracini 28, 40131 Bologna, Italy
| | - Beatriz Robles-Hernández
- Departamento de Polímeros y Materiales Avanzados: Física, Química y Tecnología, University of the Basque Country (UPV/EHU). Paseo Manuel Lardizábal 3, 20018 Donostia, Spain
- Centro de Física de Materiales (CFM, CSIC-UPV/EHU), Paseo Manuel Lardizábal 5, 20018 Donostia, Spain
| | - Giulia Guidotti
- Civil, Chemical, Environmental and Materials Engineering Department, University of Bologna, Via Terracini 28, 40131 Bologna, Italy
| | - Massimo Gazzano
- Institute of Organic Synthesis and Photoreactivity, National Research Council, Via P. Gobetti, 101, 40129 Bologna, Italy
| | - Nadia Lotti
- Civil, Chemical, Environmental and Materials Engineering Department, University of Bologna, Via Terracini 28, 40131 Bologna, Italy
| | - Angel Alegria
- Departamento de Polímeros y Materiales Avanzados: Física, Química y Tecnología, University of the Basque Country (UPV/EHU). Paseo Manuel Lardizábal 3, 20018 Donostia, Spain
- Centro de Física de Materiales (CFM, CSIC-UPV/EHU), Paseo Manuel Lardizábal 5, 20018 Donostia, Spain
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Robles-Hernández B, González E, Pomposo JA, Colmenero J, Alegría Á. Water dynamics and self-assembly of single-chain nanoparticles in concentrated solutions. Soft Matter 2020; 16:9738-9745. [PMID: 32996537 DOI: 10.1039/d0sm01447h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Single-chain polymer nanoparticles (SCNPs) are soft nano-objects consisting of uni-macromolecular chains collapsed to a certain degree by intramolecular crosslinking. The similarities between the behaviour of SCNPs and that of intrinsically disordered proteins suggest that SCNPs in concentrated solutions can be used as models to design artificial micro-environments, which mimic many of the general aspects of cellular environments. In this work, the self-assembly into SCNPs of an amphiphilic random copolymer, composed by oligo(ethylene glycol)methyl ether methacrylate (OEGMA) and 2-acetoacetoxy ethyl methacrylate (AEMA), has been investigated by means of the dielectric relaxation of water. Direct evidence of segregation of the AEMA repeating units is provided by comparison with the dielectric relaxation of water in similar solutions of the linear hydrophilic polymer, P(OEGMA). Furthermore, the results of comparative studies with similar water solutions of an amphiphilic block copolymer forming multi-chain micelles support the single-chain character of the self-assembly of the random copolymer. The overall obtained results highlight the suitability of the dielectric spectroscopy to confirm the self-assembly of the amphiphilic random copolymers into globular like core-shell single-chain nanoparticles at a concentration well above the overlap concentration.
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Affiliation(s)
- Beatriz Robles-Hernández
- Departamento de Polímeros y Materiales Avanzados, Física, Química y Tecnología, University of the Basque Country (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain.
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Robles-Hernández B, Soccio M, Castrillo I, Guidotti G, Lotti N, Alegría Á, Martínez-Tong DE. Poly(alkylene 2,5-furanoate)s thin films: Morphology, crystallinity and nanomechanical properties. POLYMER 2020. [DOI: 10.1016/j.polymer.2020.122825] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Soccio M, Martínez-Tong DE, Guidotti G, Robles-Hernández B, Munari A, Lotti N, Alegria A. Broadband Dielectric Spectroscopy Study of Biobased Poly(alkylene 2,5-furanoate)s' Molecular Dynamics. Polymers (Basel) 2020; 12:E1355. [PMID: 32560215 PMCID: PMC7361705 DOI: 10.3390/polym12061355] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/10/2020] [Accepted: 06/16/2020] [Indexed: 02/06/2023] Open
Abstract
Poly(2,5-alkylene furanoate)s are bio-based, smart, and innovative polymers that are considered the most promising materials to replace oil-based plastics. These polymers can be synthesized using ecofriendly approaches, starting from renewable sources, and result into final products with properties comparable and even better than those presented by their terephthalic counterparts. In this work, we present the molecular dynamics of four 100% bio-based poly(alkylene 2,5-furanoate)s, using broadband dielectric spectroscopy measurements that covered a wide temperature and frequency range. We unveiled complex local relaxations, characterized by the simultaneous presence of two components, which were dependent on thermal treatment. The segmental relaxation showed relaxation times and strengths depending on the glycolic subunit length, which were furthermore confirmed by high-frequency experiments in the molten region of the polymers. Our results allowed determining structure-property relations that are able to provide further understanding about the excellent barrier properties of poly(alkylene 2,5-furanoate)s. In addition, we provide results of high industrial interest during polymer processing for possible industrial applications of poly(alkylene furanoate)s.
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Affiliation(s)
- Michelina Soccio
- Civil, Chemical, Environmental and Materials Engineering Department, University of Bologna, Via Terracini 28, 40131 Bologna, Italy; (G.G.); (A.M.); (N.L.)
| | - Daniel E. Martínez-Tong
- Departamento de Física de Materiales, University of the Basque Country (UPV/EHU), P. Manuel Lardizábal 3, E-20018 San Sebastián, Spain; (B.R.-H.); (A.A.)
- Centro de Física de Materiales (CSIC–UPV/EHU), P. Manuel Lardizábal 5, E-20018 San Sebastián, Spain
| | - Giulia Guidotti
- Civil, Chemical, Environmental and Materials Engineering Department, University of Bologna, Via Terracini 28, 40131 Bologna, Italy; (G.G.); (A.M.); (N.L.)
| | - Beatriz Robles-Hernández
- Departamento de Física de Materiales, University of the Basque Country (UPV/EHU), P. Manuel Lardizábal 3, E-20018 San Sebastián, Spain; (B.R.-H.); (A.A.)
- Centro de Física de Materiales (CSIC–UPV/EHU), P. Manuel Lardizábal 5, E-20018 San Sebastián, Spain
| | - Andrea Munari
- Civil, Chemical, Environmental and Materials Engineering Department, University of Bologna, Via Terracini 28, 40131 Bologna, Italy; (G.G.); (A.M.); (N.L.)
| | - Nadia Lotti
- Civil, Chemical, Environmental and Materials Engineering Department, University of Bologna, Via Terracini 28, 40131 Bologna, Italy; (G.G.); (A.M.); (N.L.)
| | - Angel Alegria
- Departamento de Física de Materiales, University of the Basque Country (UPV/EHU), P. Manuel Lardizábal 3, E-20018 San Sebastián, Spain; (B.R.-H.); (A.A.)
- Centro de Física de Materiales (CSIC–UPV/EHU), P. Manuel Lardizábal 5, E-20018 San Sebastián, Spain
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Arbe A, Rubio-Cervilla J, Alegría A, Moreno AJ, Pomposo JA, Robles-Hernández B, Malo de Molina P, Fouquet P, Juranyi F, Colmenero J. Mesoscale Dynamics in Melts of Single-Chain Polymeric Nanoparticles. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b01264] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Arantxa Arbe
- Centro de Física de Materiales (CFM) (CSIC-UPV/EHU)-Materials Physics Center (MPC), Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
| | - Jon Rubio-Cervilla
- Centro de Física de Materiales (CFM) (CSIC-UPV/EHU)-Materials Physics Center (MPC), Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
- Departamento de Física de Materiales (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain
| | - Angel Alegría
- Centro de Física de Materiales (CFM) (CSIC-UPV/EHU)-Materials Physics Center (MPC), Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
- Departamento de Física de Materiales (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain
| | - Angel J. Moreno
- Centro de Física de Materiales (CFM) (CSIC-UPV/EHU)-Materials Physics Center (MPC), Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, E-20018 San Sebastián, Spain
| | - José A. Pomposo
- Centro de Física de Materiales (CFM) (CSIC-UPV/EHU)-Materials Physics Center (MPC), Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
- Departamento de Física de Materiales (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain
- IKERBASQUE-Basque Foundation for Science, María Díaz de Haro 3, 48013 Bilbao, Spain
| | - Beatriz Robles-Hernández
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, E-20018 San Sebastián, Spain
| | - Paula Malo de Molina
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, E-20018 San Sebastián, Spain
| | - Peter Fouquet
- Institut Laue−Langevin, BP 156, 38042 Grenoble Cedex 9, France
| | - Fanni Juranyi
- Laboratory for Neutron Scattering, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - Juan Colmenero
- Centro de Física de Materiales (CFM) (CSIC-UPV/EHU)-Materials Physics Center (MPC), Paseo Manuel de Lardizabal 5, E-20018 San Sebastián, Spain
- Departamento de Física de Materiales (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, E-20018 San Sebastián, Spain
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Robles-Hernández B, Monnier X, Pomposo JA, Gonzalez-Burgos M, Cangialosi D, Alegría A. Glassy Dynamics of an All-Polymer Nanocomposite Based on Polystyrene Single-Chain Nanoparticles. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b01257] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Beatriz Robles-Hernández
- Departamento de Física de Materiales, University of the Basque Country (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain
- Centro de Física de Materiales, Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
| | - Xavier Monnier
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain
| | - Jose A. Pomposo
- Departamento de Física de Materiales, University of the Basque Country (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain
- Centro de Física de Materiales, Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
- IKERBASQUE-Basque Foundation for Science, María Díaz de Haro 3, E-48013 Bilbao, Spain
| | - Marina Gonzalez-Burgos
- Centro de Física de Materiales, Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
| | - Daniele Cangialosi
- Centro de Física de Materiales, Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain
| | - Angel Alegría
- Departamento de Física de Materiales, University of the Basque Country (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain
- Centro de Física de Materiales, Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
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Robles-Hernández B, González-Burgos M, Pomposo JA, Colmenero J, Alegría Á. Glass-Transition Dynamics of Mixtures of Linear Poly(vinyl methyl ether) with Single-Chain Polymer Nanoparticles: Evidence of a New Type of Nanocomposite Materials. Polymers (Basel) 2019; 11:E533. [PMID: 30960517 PMCID: PMC6473516 DOI: 10.3390/polym11030533] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 03/12/2019] [Accepted: 03/18/2019] [Indexed: 01/21/2023] Open
Abstract
Single-chain polymer nanoparticles (SCNPs) obtained through chain collapse by intramolecular cross-linking are attracting increasing interest as components of all-polymer nanocomposites, among other applications. We present a dielectric relaxation study on the dynamics of mixtures of poly(vinyl methyl ether) (PVME) and polystyrene (PS)-based SCNPs with various compositions. Analogous dielectric measurements on a miscible blend of PVME with the linear precursor chains of the SCNPs are taken as reference for this study. Both systems present completely different behaviors: While the blend with the linear precursor presents dynamics very similar to that reported for PVME/PS miscible blends, in the PVME/SCNP mixtures there are an appreciable amount of PVME segments that are barely affected by the presence of SCNPs, which nearly vanishes only for mixtures with high SCNP content. Interestingly, in the frame of a simple two-phase system, our findings point towards the existence of a SCNP-rich phase with a constant PVME fraction, regardless of the overall concentration of the mixture. Moreover, the dynamics of the PVME segments in this SCNP-rich phase display an extreme dynamic heterogeneity, a signature of constraint effects.
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Affiliation(s)
- Beatriz Robles-Hernández
- Departamento de Física de Materiales, University of the Basque Country (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain.
- Donostia International Physics Center (DIPC), Paseo Manuel Lardizábal 4, 20018 San Sebastián, Spain.
| | - Marina González-Burgos
- Materials Physics Center, CSIC-UPV/EHU, Paseo Manuel Lardizábal 5, 20018 San Sebastián, Spain.
| | - José A Pomposo
- Departamento de Física de Materiales, University of the Basque Country (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain.
- Materials Physics Center, CSIC-UPV/EHU, Paseo Manuel Lardizábal 5, 20018 San Sebastián, Spain.
- IKERBASQUE-Basque Foundation for Science, María Díaz de Haro 3, E-48013 Bilbao, Spain.
| | - Juan Colmenero
- Departamento de Física de Materiales, University of the Basque Country (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain.
- Donostia International Physics Center (DIPC), Paseo Manuel Lardizábal 4, 20018 San Sebastián, Spain.
- Materials Physics Center, CSIC-UPV/EHU, Paseo Manuel Lardizábal 5, 20018 San Sebastián, Spain.
| | - Ángel Alegría
- Departamento de Física de Materiales, University of the Basque Country (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain.
- Materials Physics Center, CSIC-UPV/EHU, Paseo Manuel Lardizábal 5, 20018 San Sebastián, Spain.
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11
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Rubio-Cervilla J, Malo de Molina P, Robles-Hernández B, Arbe A, Moreno AJ, Alegría A, Colmenero J, Pomposo JA. Facile Access to Completely Deuterated Single-Chain Nanoparticles Enabled by Intramolecular Azide Photodecomposition. Macromol Rapid Commun 2019; 40:e1900046. [PMID: 30801882 DOI: 10.1002/marc.201900046] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Indexed: 01/14/2023]
Abstract
Access to completely deuterated single-chain nanoparticles (dSCNPs) has remained an unresolved issue. Herein, the first facile and efficient procedure to produce dSCNPs is reported, which comprises: i) the use of commercially available perdeuterated cyclic ether monomers as starting reagents, ii) a ring-opening copolymerization process performed in bulk to produce a neat dSCNP precursor, iii) a standard azidation reaction to decorate this precursor with azide moieties, and iv) a facile intramolecular azide photodecomposition step carried out under UV irradiation at high dilution providing with highly valuable, completely deuterated soft nano-objects from the precursor. dSCNPs are used to investigate by means of neutron-scattering measurements the form factor (radius of gyration, scaling exponent) of polyethylene oxide (PEO) chains in nanocomposites with different amounts of dSCNPs. Moreover, to illustrate the possibilities offered by the synthetic route disclosed in this communication for potential applications, the significant reduction in viscosity observed in a pure melt of polyether-based single-chain nanoparticles when compared to a melt of the corresponding linear polymer chains is shown.
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Affiliation(s)
- Jon Rubio-Cervilla
- Centro de Física de Materiales (CSIC, UPV/EHU)-MPC Materials Physics Center, Paseo Manuel de Lardizabal 5, 20018, San Sebastian, Spain
| | - Paula Malo de Molina
- Centro de Física de Materiales (CSIC, UPV/EHU)-MPC Materials Physics Center, Paseo Manuel de Lardizabal 5, 20018, San Sebastian, Spain.,Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018, San Sebastian, Spain
| | - Beatriz Robles-Hernández
- Centro de Física de Materiales (CSIC, UPV/EHU)-MPC Materials Physics Center, Paseo Manuel de Lardizabal 5, 20018, San Sebastian, Spain.,Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018, San Sebastian, Spain
| | - Arantxa Arbe
- Centro de Física de Materiales (CSIC, UPV/EHU)-MPC Materials Physics Center, Paseo Manuel de Lardizabal 5, 20018, San Sebastian, Spain
| | - Angel J Moreno
- Centro de Física de Materiales (CSIC, UPV/EHU)-MPC Materials Physics Center, Paseo Manuel de Lardizabal 5, 20018, San Sebastian, Spain.,Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018, San Sebastian, Spain
| | - Angel Alegría
- Centro de Física de Materiales (CSIC, UPV/EHU)-MPC Materials Physics Center, Paseo Manuel de Lardizabal 5, 20018, San Sebastian, Spain.,Departamento de Física de Materiales, Universidad del País Vasco (UPV/EHU), Apartado 1072, 20080, San Sebastian, Spain
| | - Juan Colmenero
- Centro de Física de Materiales (CSIC, UPV/EHU)-MPC Materials Physics Center, Paseo Manuel de Lardizabal 5, 20018, San Sebastian, Spain.,Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018, San Sebastian, Spain.,Departamento de Física de Materiales, Universidad del País Vasco (UPV/EHU), Apartado 1072, 20080, San Sebastian, Spain
| | - José A Pomposo
- Centro de Física de Materiales (CSIC, UPV/EHU)-MPC Materials Physics Center, Paseo Manuel de Lardizabal 5, 20018, San Sebastian, Spain.,Departamento de Física de Materiales, Universidad del País Vasco (UPV/EHU), Apartado 1072, 20080, San Sebastian, Spain.,IKERBASQUE-Basque Foundation for Science, María Díaz de Haro 3, 48013, Bilbao, Spain
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12
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Paterson DA, Gao M, Kim YK, Jamali A, Finley KL, Robles-Hernández B, Diez-Berart S, Salud J, de la Fuente MR, Timimi BA, Zimmermann H, Greco C, Ferrarini A, Storey JMD, López DO, Lavrentovich OD, Luckhurst GR, Imrie CT. Understanding the twist-bend nematic phase: the characterisation of 1-(4-cyanobiphenyl-4'-yloxy)-6-(4-cyanobiphenyl-4'-yl)hexane (CB6OCB) and comparison with CB7CB. Soft Matter 2016; 12:6827-6840. [PMID: 27447288 DOI: 10.1039/c6sm00537c] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The synthesis and characterisation of the nonsymmetric liquid crystal dimer, 1-(4-cyanobiphenyl-4'-yloxy)-6-(4-cyanobiphenyl-4'-yl)hexane (CB6OCB) is reported. An enantiotropic nematic (N)-twist-bend nematic (NTB) phase transition is observed at 109 °C and a nematic-isotropic phase transition at 153 °C. The NTB phase assignment has been confirmed using polarised light microscopy, freeze fracture transmission electron microscopy (FFTEM), (2)H-NMR spectroscopy, and X-ray diffraction. The effective molecular length in both the NTB and N phases indicates a locally intercalated arrangement of the molecules, and the helicoidal pitch length in the NTB phase is estimated to be 8.9 nm. The surface anchoring properties of CB6OCB on a number of aligning layers is reported. A Landau model is applied to describe high-resolution heat capacity measurements in the vicinity of the NTB-N phase transition. Both the theory and heat capacity measurements agree with a very weak first-order phase transition. A complementary extended molecular field theory was found to be in suggestive accord with the (2)H-NMR studies of CB6OCB-d2, and those already known for CB7CB-d4. These include the reduced transition temperature, TNTBN/TNI, the order parameter of the mesogenic arms in the N phase close to the NTB-N transition, and the order parameter with respect to the helix axis which is related to the conical angle for the NTB phase.
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Affiliation(s)
- Daniel A Paterson
- Department of Chemistry, School of Natural and Computing Sciences, University of Aberdeen, Meston Building, Aberdeen, AB24 3UE, UK.
| | - Min Gao
- Liquid Crystal Institute and Chemical Physics Interdisciplinary Program, Kent State University, Kent, OH 44242, USA
| | - Young-Ki Kim
- Liquid Crystal Institute and Chemical Physics Interdisciplinary Program, Kent State University, Kent, OH 44242, USA
| | - Afsoon Jamali
- Liquid Crystal Institute and Chemical Physics Interdisciplinary Program, Kent State University, Kent, OH 44242, USA
| | - Kirsten L Finley
- Department of Physics, Polytechnic University of Catalonia, Barcelona, Spain
| | | | - Sergio Diez-Berart
- Department of Physics, Polytechnic University of Catalonia, Barcelona, Spain
| | - Josep Salud
- Department of Physics, Polytechnic University of Catalonia, Barcelona, Spain
| | - M Rosario de la Fuente
- Department of Applied Physics II, University of the Basque Country, E-48080 Bilbao, Spain
| | - Bakir A Timimi
- Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
| | - Herbert Zimmermann
- Max-Planck-Institut für Medizinische Förschung, D-69120 Heidelberg, Germany
| | - Cristina Greco
- Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo 1, 35121 Padova, Italy
| | - Alberta Ferrarini
- Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo 1, 35121 Padova, Italy
| | - John M D Storey
- Department of Chemistry, School of Natural and Computing Sciences, University of Aberdeen, Meston Building, Aberdeen, AB24 3UE, UK.
| | - David O López
- Department of Physics, Polytechnic University of Catalonia, Barcelona, Spain
| | - Oleg D Lavrentovich
- Liquid Crystal Institute and Chemical Physics Interdisciplinary Program, Kent State University, Kent, OH 44242, USA
| | | | - Corrie T Imrie
- Department of Chemistry, School of Natural and Computing Sciences, University of Aberdeen, Meston Building, Aberdeen, AB24 3UE, UK.
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13
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Martínez-Abadía M, Robles-Hernández B, de la Fuente MR, Giménez R, Ros MB. Photoresponsive Cyanostilbene Bent-Core Liquid Crystals as New Materials with Light-Driven Modulated Polarization. Adv Mater 2016; 28:6586-6591. [PMID: 27213889 DOI: 10.1002/adma.201600311] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 04/25/2016] [Indexed: 06/05/2023]
Abstract
Two isomeric cyanostilbene photoswitchable bent-core mesogens with polar liquid crystal phases in which macroscopic polarization and luminescence can be light-modulated are introduced. Z/E isomerization or [2+2] cycloaddition photochemical processes occur depending on the chemical structure, which make the compounds very innovative multifunctional advanced materials.
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Affiliation(s)
- Marta Martínez-Abadía
- Instituto de Ciencia de Materiales de Aragón (ICMA), Departamento de Química Orgánica - Facultad de Ciencias, Universidad de Zaragoza-CSIC, 50009, Zaragoza, Spain
| | - Beatriz Robles-Hernández
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco UPV/EHU, 48080, Bilbao, Spain
| | - María Rosario de la Fuente
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco UPV/EHU, 48080, Bilbao, Spain
| | - Raquel Giménez
- Instituto de Ciencia de Materiales de Aragón (ICMA), Departamento de Química Orgánica - Facultad de Ciencias, Universidad de Zaragoza-CSIC, 50009, Zaragoza, Spain
| | - Maria Blanca Ros
- Instituto de Ciencia de Materiales de Aragón (ICMA), Departamento de Química Orgánica - Facultad de Ciencias, Universidad de Zaragoza-CSIC, 50009, Zaragoza, Spain
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14
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Robles-Hernández B, Sebastián N, Salud J, Diez-Berart S, Dunmur DA, Luckhurst GR, López DO, de la Fuente MR. Molecular dynamics of a binary mixture of twist-bend nematic liquid crystal dimers studied by dielectric spectroscopy. Phys Rev E 2016; 93:062705. [PMID: 27415332 DOI: 10.1103/physreve.93.062705] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Indexed: 06/06/2023]
Abstract
We report a comprehensive dielectric characterization of a liquid crystalline binary mixture composed of the symmetric mesogenic dimer CB7CB and the nonsymmetric mesogenic dimer FFO9OCB. In addition to the high-temperature nematic phase, such a binary mixture shows a twist-bend nematic phase at room temperature which readily vitrifies on slow cooling. Changes in the conformational distribution of the dimers are reflected in the dielectric permittivity and successfully analyzed by means of an appropriate theoretical model. It is shown that the dielectric spectra of the mixture reflect the different molecular dipole properties of the components, resembling in the present case the characteristic dielectric spectra of nonsymmetric dimers. Comparison of the nematic and twist-bend nematic phases reveals that molecular dynamics are similar despite the difference in the molecular environment.
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Affiliation(s)
- Beatriz Robles-Hernández
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apartado 644, E-48080 Bilbao, Spain
| | - Nerea Sebastián
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apartado 644, E-48080 Bilbao, Spain
- Otto-von-Guericke Universitat Magdeburg, Institute for Experimental Physics, ANP, 39106 Magdeburg, Germany
| | - Josep Salud
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, E-08028 Barcelona, Spain
| | - Sergio Diez-Berart
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, E-08028 Barcelona, Spain
| | - David A Dunmur
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Geoffrey R Luckhurst
- Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, United Kingdom
| | - David O López
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, E-08028 Barcelona, Spain
| | - M Rosario de la Fuente
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apartado 644, E-48080 Bilbao, Spain
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15
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López DO, Robles-Hernández B, Salud J, de la Fuente MR, Sebastián N, Diez-Berart S, Jaen X, Dunmur DA, Luckhurst GR. Correction: Miscibility studies of two twist-bend nematic liquid crystal dimers with different average molecular curvatures. A comparison between experimental data and predictions of a Landau mean-field theory for the NTB-N phase transition. Phys Chem Chem Phys 2016; 18:6955. [PMID: 26877266 DOI: 10.1039/c6cp90042a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Correction for 'Miscibility studies of two twist-bend nematic liquid crystal dimers with different average molecular curvatures. A comparison between experimental data and predictions of a Landau mean-field theory for the NTB-N phase transition' by D. O. López et al., Phys. Chem. Chem. Phys., 2016, 18, 4394-4404.
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Affiliation(s)
- D O López
- Grup de Propietats Físiques dels Materials (GRPFM-GCMM), Departament de Física, E.T.S.E.I.B, Universitat Politècnica de Catalunya, Diagonal, 647 08028 Barcelona, Spain.
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16
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López DO, Robles-Hernández B, Salud J, de la Fuente MR, Sebastián N, Diez-Berart S, Jaen X, Dunmur DA, Luckhurst GR. Miscibility studies of two twist-bend nematic liquid crystal dimers with different average molecular curvatures. A comparison between experimental data and predictions of a Landau mean-field theory for the NTB–N phase transition. Phys Chem Chem Phys 2016; 18:4394-404. [DOI: 10.1039/c5cp07605f] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have developed a Landau model that predicts a first order twist-bend nematic–nematic phase transition.
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Affiliation(s)
- D. O. López
- Grup de Propietats Físiques dels Materials (GRPFM-GCMM)
- Departament de Física
- E.T.S.E.I.B
- Universitat Politècnica de Catalunya
- 647 08028 Barcelona
| | - B. Robles-Hernández
- Grup de Propietats Físiques dels Materials (GRPFM-GCMM)
- Departament de Física
- E.T.S.E.I.B
- Universitat Politècnica de Catalunya
- 647 08028 Barcelona
| | - J. Salud
- Grup de Propietats Físiques dels Materials (GRPFM-GCMM)
- Departament de Física
- E.T.S.E.I.B
- Universitat Politècnica de Catalunya
- 647 08028 Barcelona
| | - M. R. de la Fuente
- Departamento de Física Aplicada II
- Facultad de Ciencia y Tecnología
- Universidad del País Vasco
- E-48080 Bilbao
- Spain
| | - N. Sebastián
- Institute for Experimental Physics
- Otto-von-Guerike Universität Magdeburg
- ANP
- 39106 Magdeburg
- Germany
| | - S. Diez-Berart
- Grup de Propietats Físiques dels Materials (GRPFM-GCMM)
- Departament de Física
- E.T.S.E.I.B
- Universitat Politècnica de Catalunya
- 647 08028 Barcelona
| | - X. Jaen
- Grup de Propietats Físiques dels Materials (GRPFM-GCMM)
- Departament de Física
- E.T.S.E.I.B
- Universitat Politècnica de Catalunya
- 647 08028 Barcelona
| | - D. A. Dunmur
- School of Physics and Astronomy
- University of Manchester
- Manchester M13 9PL
- UK
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17
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Robles-Hernández B, Sebastián N, de la Fuente MR, López DO, Diez-Berart S, Salud J, Ros MB, Dunmur DA, Luckhurst GR, Timimi BA. Twist, tilt, and orientational order at the nematic to twist-bend nematic phase transition of 1″,9″-bis(4-cyanobiphenyl-4'-yl) nonane: A dielectric, (2)H NMR, and calorimetric study. Phys Rev E Stat Nonlin Soft Matter Phys 2015; 92:062505. [PMID: 26764709 DOI: 10.1103/physreve.92.062505] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Indexed: 06/05/2023]
Abstract
The nature of the nematic-nematic phase transition in the liquid crystal dimer 1″,9″-bis(4-cyanobiphenyl-4'-yl) nonane (CB9CB) has been investigated using techniques of calorimetry, dynamic dielectric response measurements, and (2)H NMR spectroscopy. The experimental results for CB9CB show that, like the shorter homologue CB7CB, the studied material exhibits a normal nematic phase, which on cooling undergoes a transition to the twist-bend nematic phase (N(TB)), a uniaxial nematic phase, promoted by the average bent molecular shape, in which the director tilts and precesses describing a conical helix. Modulated differential scanning calorimetry has been used to analyze the nature of the N(TB)-N phase transition, which is found to be weakly first order, but close to tricritical. Additionally broadband dielectric spectroscopy and (2)H magnetic resonance studies have revealed information on the structural characteristics of the recently discovered twist-bend nematic phase. Analysis of the dynamic dielectric response in both nematic phases has provided an estimate of the conical angle of the heliconical structure for the N(TB) phase. Capacitance measurements of the electric-field realignment of the director in initially planar aligned cells have yielded values for the splay and bend elastic constants in the high temperature nematic phase. The bend elastic constant is small and decreases with decreasing temperature as the twist-bend phase is approached. This behavior is expected theoretically and has been observed in materials that form the twist-bend nematic phase. (2)H NMR measurements characterize the chiral helical twist identified in the twist-bend nematic phase and also allow the determination of the temperature dependence of the conical angle and the orientational order parameter with respect to the director.
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Affiliation(s)
- Beatriz Robles-Hernández
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apartado 644, E-48080 Bilbao, Spain
| | - Nerea Sebastián
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apartado 644, E-48080 Bilbao, Spain
- Otto-von-Guericke Universitat Magdeburg, Institute for Experimental Physics, ANP, 39106 Magdeburg, Germany
| | - M Rosario de la Fuente
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apartado 644, E-48080 Bilbao, Spain
| | - David O López
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física i Enginyeria Nuclear, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, E- 08028 Barcelona, Spain
| | - Sergio Diez-Berart
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física i Enginyeria Nuclear, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, E- 08028 Barcelona, Spain
| | - Josep Salud
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física i Enginyeria Nuclear, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, E- 08028 Barcelona, Spain
| | - M Blanca Ros
- Departamento de Química Orgánica, Facultad de Ciencias-Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, E-50009 Zaragoza, Spain
| | - David A Dunmur
- Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, United Kingdom
| | - Geoffrey R Luckhurst
- Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, United Kingdom
| | - Bakir A Timimi
- Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, United Kingdom
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18
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Diez-Berart S, López DO, Salud J, Diego JA, Sellarès J, Robles-Hernández B, de la Fuente MR, Ros MB. Two Glass Transitions Associated to Different Dynamic Disorders in the Nematic Glassy State of a Non-Symmetric Liquid Crystal Dimer Dopped with g-Alumina Nanoparticles. Materials 2015. [PMCID: PMC5455711 DOI: 10.3390/ma8063334] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In the present work, the nematic glassy state of the non-symmetric LC dimer α-(4-cyanobiphenyl-4′-yloxy)-ω-(1-pyrenimine-benzylidene-4′-oxy) undecane is studied by means of calorimetric and dielectric measurements. The most striking result of the work is the presence of two different glass transition temperatures: one due to the freezing of the flip-flop motions of the bulkier unit of the dimer and the other, at a lower temperature, related to the freezing of the flip-flop and precessional motions of the cyanobiphenyl unit. This result shows the fact that glass transition is the consequence of the freezing of one or more coupled dynamic disorders and not of the disordered phase itself. In order to avoid crystallization when the bulk sample is cooled down, the LC dimer has been confined via the dispersion of γ-alumina nanoparticles, in several concentrations.
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Affiliation(s)
- Sergio Diez-Berart
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física i Enginyeria Nuclear, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, Barcelona 08028, Spain; E-Mails: (D.O.L.); (J.S.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +34-934-054-107; Fax: +34-934-011-839
| | - David O. López
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física i Enginyeria Nuclear, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, Barcelona 08028, Spain; E-Mails: (D.O.L.); (J.S.)
| | - Josep Salud
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física i Enginyeria Nuclear, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, Barcelona 08028, Spain; E-Mails: (D.O.L.); (J.S.)
| | - José Antonio Diego
- Dielectric Materials Physics Laboratory (DILAB), Departament de Física i Enginyeria Nuclear, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Colom 11, Terrassa 08222, Spain; E-Mails: (J.A.D.); (J.S.)
| | - Jordi Sellarès
- Dielectric Materials Physics Laboratory (DILAB), Departament de Física i Enginyeria Nuclear, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Colom 11, Terrassa 08222, Spain; E-Mails: (J.A.D.); (J.S.)
| | - Beatriz Robles-Hernández
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco UPV-EHU, Apartado 644, Bilbao 48080, Spain; E-Mails: (B.R.-H.); (M.R.F.)
| | - María Rosario de la Fuente
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco UPV-EHU, Apartado 644, Bilbao 48080, Spain; E-Mails: (B.R.-H.); (M.R.F.)
| | - María Blanca Ros
- Instituto de Ciencia de Materiales de Aragón (ICMA), Departamento de Química Orgánica-Facultad de Ciencias, Universidad de Zaragoza-CSIC, Zaragoza 50009, Spain; E-Mail:
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Sebastián N, López DO, Robles-Hernández B, de la Fuente MR, Salud J, Pérez-Jubindo MA, Dunmur DA, Luckhurst GR, Jackson DJB. Dielectric, calorimetric and mesophase properties of 1′′-(2′,4-difluorobiphenyl-4′-yloxy)-9′′-(4-cyanobiphenyl-4′-yloxy) nonane: an odd liquid crystal dimer with a monotropic mesophase having the characteristics of a twist-bend nematic phase. Phys Chem Chem Phys 2014; 16:21391-406. [DOI: 10.1039/c4cp03462g] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Diez-Berart S, López DO, Sebastián N, de la Fuente MR, Salud J, Robles-Hernández B, Pérez-Jubindo MÁ. Dispersion of γ-Alumina Nano-Sized Spherical Particles in a Calamitic Liquid Crystal. Study and Optimization of the Confinement Effects. Materials (Basel) 2014; 7:1502-1519. [PMID: 28788528 PMCID: PMC5453256 DOI: 10.3390/ma7031502] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 02/05/2014] [Accepted: 02/12/2014] [Indexed: 11/16/2022]
Abstract
We report an experimental study on confined systems formed by butyloxybenzylidene octylaniline liquid crystal (4O.8) + γ-alumina nanoparticles. The effects of the confinement in the thermal and dielectric properties of the liquid crystal under different densities of nanoparticles is analyzed by means of high resolution Modulated Differential Scanning Calorimetry (MDSC) and broadband dielectric spectroscopy. First, a drastic depression of the N-I and SmA-N transition temperatures is observed with confinement, the more concentration of nanoparticles the deeper this depression is, driving the nematic range closer to the room temperature. An interesting experimental law is found for both transition temperatures. Second, the change in shape of the heat capacity peaks is quantified by means of the full width half maximum (FWHM). Third, the confinement does not noticeably affect the molecular dynamics. Finally, the combination of nanoparticles and the external applied electric field tends to favor the alignment of the molecules in metallic cells. All these results indicate that the confinement of liquid crystals by means of γ-alumina nanoparticles could be optimum for liquid crystal-based electrooptic devices.
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Affiliation(s)
- Sergio Diez-Berart
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco UPV-EHU, Apartado 644, Bilbao E-48080,
Spain; E-Mails: (D.O.L.); (N.S.); (M.R.F.); (B.R.-H.); (M.A.P.-J.)
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física i Enginyeria Nuclear, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, Barcelona 08028,
Spain; E-Mail:
| | - David O. López
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco UPV-EHU, Apartado 644, Bilbao E-48080,
Spain; E-Mails: (D.O.L.); (N.S.); (M.R.F.); (B.R.-H.); (M.A.P.-J.)
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física i Enginyeria Nuclear, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, Barcelona 08028,
Spain; E-Mail:
| | - Nerea Sebastián
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco UPV-EHU, Apartado 644, Bilbao E-48080,
Spain; E-Mails: (D.O.L.); (N.S.); (M.R.F.); (B.R.-H.); (M.A.P.-J.)
| | - María Rosario de la Fuente
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco UPV-EHU, Apartado 644, Bilbao E-48080,
Spain; E-Mails: (D.O.L.); (N.S.); (M.R.F.); (B.R.-H.); (M.A.P.-J.)
| | - Josep Salud
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física i Enginyeria Nuclear, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, Barcelona 08028,
Spain; E-Mail:
| | - Beatriz Robles-Hernández
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco UPV-EHU, Apartado 644, Bilbao E-48080,
Spain; E-Mails: (D.O.L.); (N.S.); (M.R.F.); (B.R.-H.); (M.A.P.-J.)
- Grup de Propietas Físiques dels Materials (GRPFM), Departament de Física i Enginyeria Nuclear, E.T.S.E.I.B. Universitat Politècnica de Catalunya, Diagonal 647, Barcelona 08028,
Spain; E-Mail:
| | - Miguel Ángel Pérez-Jubindo
- Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco UPV-EHU, Apartado 644, Bilbao E-48080,
Spain; E-Mails: (D.O.L.); (N.S.); (M.R.F.); (B.R.-H.); (M.A.P.-J.)
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Beltrán E, Robles-Hernández B, Sebastián N, Serrano JL, Giménez R, Sierra T. Bent-core luminescent and electroactive bis(triazolyl)triazines with compact columnar mesomorphism. RSC Adv 2014. [DOI: 10.1039/c4ra02926g] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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