Segmental Relaxation of Hydrophilic Poly(vinylpyrrolidone) in Chloroform Studied by Broadband Dielectric Spectroscopy

2011 ◽  
Vol 44 (7) ◽  
pp. 2140-2148 ◽  
Author(s):  
Naoki Shinyashiki ◽  
Anna Spanoudaki ◽  
Wataru Yamamoto ◽  
Eri Nambu ◽  
Kaoru Yoneda ◽  
...  
Keyword(s):  
Dielectric Spectroscopy ◽  
Broadband Dielectric Spectroscopy ◽  
Segmental Relaxation

scholarly journals Broadband Dielectric Spectroscopy Study of Biobased Poly(alkylene 2,5-furanoate)s’ Molecular Dynamics

Polymers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1355 ◽  
Author(s):  
Michelina Soccio ◽  
Daniel E. Martínez-Tong ◽  
Giulia Guidotti ◽  
Beatriz Robles-Hernández ◽  
Andrea Munari ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Dielectric Spectroscopy ◽  
Relaxation Times ◽  
Barrier Properties ◽  
Polymer Processing ◽  
Industrial Applications ◽  
Structure Property ◽  
Property Relations ◽  
Broadband Dielectric Spectroscopy ◽  
Segmental Relaxation

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.

scholarly journals Broadband dielectric spectroscopy for monitoring temperature-dependent chloride ion motion in BiOCl plates

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Adrian Radoń ◽  
Dariusz Łukowiec ◽  
Patryk Włodarczyk
Keyword(s):  
Electrical Conductivity ◽  
Dielectric Spectroscopy ◽  
Low Frequency ◽  
Chloride Ion ◽  
Ion Source ◽  
Chloride Ions ◽  
Ion Concentration ◽  
Broadband Dielectric Spectroscopy ◽  
Free Chloride ◽  
Structure Rebuilding

AbstractThe dielectric properties and electrical conduction mechanism of bismuth oxychloride (BiOCl) plates synthesized using chloramine-T as the chloride ion source were investigated. Thermally-activated structure rebuilding was monitored using broadband dielectric spectroscopy, which showed that the onset temperature of this process was 283 K. This rebuilding was related to the introduction of free chloride ions into [Bi2O2]2+ layers and their growth, which increased the intensity of the (101) diffraction peak. The electrical conductivity and dielectric permittivity were related to the movement of chloride ions between plates (in the low-frequency region), the interplanar motion of Cl− ions at higher frequencies, vibrations of these ions, and charge carrier hopping at frequencies above 10 kHz. The influence of the free chloride ion concentration on the electrical conductivity was also described. Structure rebuilding was associated with a lower concentration of free chloride ions, which significantly decreased the conductivity. According to the analysis, the BiOCl plate conductivity was related to the movement of Cl− ions, not electrons.

Broadband dielectric spectroscopy on glycerol and CKN

1996 ◽  
Vol 176 (1) ◽  
pp. 33-41 ◽  
Author(s):  
A. Pimenov ◽  
P. Lunkenheimer ◽  
A. Loidl
Keyword(s):  
Dielectric Spectroscopy ◽  
Broadband Dielectric Spectroscopy
Sign in / Sign up

Export Citation Format

Share Document