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Gonzales KN, Troncoso OP, Torres FG, López D. Molecular α-relaxation process of exopolysaccharides extracted from Nostoc commune cyanobacteria. Int J Biol Macromol 2020; 161:1516-1525. [PMID: 32755710 DOI: 10.1016/j.ijbiomac.2020.07.268] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 07/04/2020] [Accepted: 07/20/2020] [Indexed: 01/25/2023]
Abstract
Broadband dielectric spectroscopy was used to investigate the molecular α-relaxation of the exopolysaccharides (EPS) extracted from Nostoc commune cyanobacteria. The EPS were modified in different ways. EPS were carboxymethylated to obtain carboxymethyl-exopolysaccharides (CEPS). EPS and CEPS were doped with ammonium iodide and 1-butyl-3-methylimidazolium chloride. An α relaxation process was observed for all specimens. The temperature dependence of the relaxation times for pure and doped, EPS and CEPS polymers exhibited non-Arrhenius behavior. This relaxation process was associated with the glass transition of the complex heteropolysaccharides produced by the cyanobacteria. The molecular mobility at the glass transition, Tg, was affected by both the carboxymethylation treatment and the doping. The fragility index also decreased for the doped specimens, which may be attributed to an increase in the mobility of the polymer chains due to the plasticizing effect of the doping agents.
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Affiliation(s)
- Karen N Gonzales
- Department of Mechanical Engineering, Pontificia Universidad Católica del Perú (Lima 32 Perú). Av. Universitaria 1801, Lima 32, Lima, Peru
| | - Omar P Troncoso
- Department of Mechanical Engineering, Pontificia Universidad Católica del Perú (Lima 32 Perú). Av. Universitaria 1801, Lima 32, Lima, Peru
| | - Fernando G Torres
- Department of Mechanical Engineering, Pontificia Universidad Católica del Perú (Lima 32 Perú). Av. Universitaria 1801, Lima 32, Lima, Peru.
| | - Daniel López
- Institute of Polymer Science and Technology, Spanish Council for Scientific Research (ICTP-CSIC), Madrid, Spain
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Abstract
The PVP and its derivatives have been broadly applied in polymers, organic
syntheses, and catalysis processes. The crosslinked PVP is a well-known polymer support
for numerous reagents and catalysts. Cross-linked PVPs are commercially available polymers
and have attracted much attention over the past due to their interesting properties
such as the facile functionalization, high accessibility of functional groups, being nonhygroscopic,
easy to prepare, easy filtration, and swelling in many organic solvents. A
brief explanation of the reported applications of PVPs in different fields followed by the
discussion on the implementation of methodologies for catalytic efficiency of PVP-based
reagents in the organic synthesis is included. The aim is to summarize the literature under
a few catalytic categories and to present each as a short scheme involving reaction conditions.
In the text, discussions on the synthesis and the structural determination of some typical polymeric reagents
are presented, and the mechanisms of some organic reactions are given. Where appropriate, advantages
of reagents in comparison with the previous reports are presented. This review does not include patent literature.
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Affiliation(s)
- Nader Ghaffari Khaligh
- Nanotechnology and Catalysis Research Center, Institute of Postgraduate Studies, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Hanna S. Abbo
- Department of Chemistry, University of Basrah, Basrah, Iraq
| | - Mohd Rafie Johan
- Nanotechnology and Catalysis Research Center, Institute of Postgraduate Studies, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Liu X, Jeong KS, Williams BP, Vakhshouri K, Guo C, Han K, Gomez ED, Wang Q, Asbury JB. Tuning the Dielectric Properties of Organic Semiconductors via Salt Doping. J Phys Chem B 2013; 117:15866-74. [DOI: 10.1021/jp408537p] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xien Liu
- Department
of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Kwang S. Jeong
- Department
of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Bryan P. Williams
- Department
of Chemical Engineering and the Materials Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Kiarash Vakhshouri
- Department
of Chemical Engineering and the Materials Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Changhe Guo
- Department
of Chemical Engineering and the Materials Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Kuo Han
- Department
of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Enrique D. Gomez
- Department
of Chemical Engineering and the Materials Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Qing Wang
- Department
of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - John B. Asbury
- Department
of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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Naidu S, Ahn H, Gong J, Kim B, Ryu DY. Phase Behavior and Ionic Conductivity of Lithium Perchlorate-Doped Polystyrene-b-poly(2-vinylpyridine) Copolymer. Macromolecules 2011. [DOI: 10.1021/ma200429v] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sudhakar Naidu
- Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul 120-749, Korea
| | - Hyungju Ahn
- Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul 120-749, Korea
| | - Jinsam Gong
- Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul 120-749, Korea
| | - Bokyung Kim
- Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul 120-749, Korea
| | - Du Yeol Ryu
- Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul 120-749, Korea
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Kim B, Ahn H, Kim JH, Ryu DY, Kim J. Transition behavior and ionic conductivity of lithium perchlorate-doped polystyrene-b-poly(2-vinylpyridine). POLYMER 2009. [DOI: 10.1016/j.polymer.2009.05.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Fragiadakis D, Dou S, Colby RH, Runt J. Molecular mobility and Li+ conduction in polyester copolymer ionomers based on poly(ethylene oxide). J Chem Phys 2009; 130:064907. [DOI: 10.1063/1.3063659] [Citation(s) in RCA: 161] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Ioannou EF, Mountrichas G, Pispas S, Kamitsos EI, Floudas G. Lithium Ion Induced Nanophase Ordering and Ion Mobility in Ionic Block Copolymers. Macromolecules 2008. [DOI: 10.1021/ma8008542] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Eirini F. Ioannou
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vass. Constantinou Ave., 116 35, Athens, Greece
| | - Grigoris Mountrichas
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vass. Constantinou Ave., 116 35, Athens, Greece
| | - Stergios Pispas
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vass. Constantinou Ave., 116 35, Athens, Greece
| | - Efstratios I. Kamitsos
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vass. Constantinou Ave., 116 35, Athens, Greece
| | - George Floudas
- Department of Physics, University of Ioannina, P.O. Box 1186, 451 10, Ioannina, Greece, and Foundation for Research and Technology−Hellas, Biomedical Research Institute (FORTH-BRI)
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