Heterogeneity of the Segmental Dynamics of Poly(dimethylsiloxane) in a Diblock Lamellar Mesophase:  Dielectric Relaxation Investigations

2004 ◽  
Vol 37 (20) ◽  
pp. 7808-7817 ◽  
Author(s):  
C. Lorthioir ◽  
A. Alegría ◽  
J. Colmenero ◽  
B. Deloche
Keyword(s):  
Dielectric Relaxation ◽  
Segmental Dynamics

scholarly journals Effect of soft segment molecular weight on the glass transition, crystallinity, molecular mobility and segmental dynamics of poly(ethylene oxide) based poly(urethane–urea) copolymers

RSC Advances ◽  
2017 ◽  
Vol 7 (65) ◽  
pp. 40745-40754 ◽  
Author(s):  
Oguzhan Oguz ◽  
Stefanos A. Koutsoumpis ◽  
Eren Simsek ◽  
Emel Yilgor ◽  
Iskender Yilgor ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Glass Transition ◽  
Ethylene Oxide ◽  
Dielectric Relaxation ◽  
Molecular Mobility ◽  
Soft Segment ◽  
Dielectric Relaxation Spectroscopy ◽  
Segmental Dynamics ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

The effect of poly(ethylene oxide) (PEO) soft segment molecular weight (Mn= 2000, 4600, 8000 g mol−1) molecular mobility and segmental dynamics of a series of polyurethane–urea copolymers (PU) was investigated by dielectric relaxation spectroscopy.

Dynamics of a bioinert polymer in hydrated states by dielectric relaxation spectroscopy

2017 ◽  
Vol 19 (2) ◽  
pp. 1389-1394 ◽  
Author(s):  
Toyoaki Hirata ◽  
Hisao Matsuno ◽  
Daisuke Kawaguchi ◽  
Manabu Inutsuka ◽  
Tomoyasu Hirai ◽  
...  
Keyword(s):  
Dielectric Relaxation ◽  
Side Chain ◽  
Water Interface ◽  
Dielectric Relaxation Spectroscopy ◽  
Segmental Dynamics ◽  
Side Chain Motion

The segmental dynamics of poly(2-methoxyethyl acrylate) at the water interface is extremely faster and comparable to the side chain motion.

Dielectric relaxation of polymers: segmental dynamics under structural constraints

Soft Matter ◽  
2016 ◽  
Vol 12 (37) ◽  
pp. 7709-7725 ◽  
Author(s):  
Angel Alegria ◽  
Juan Colmenero
Keyword(s):  
Dielectric Relaxation ◽  
Structural Constraints ◽  
Segmental Dynamics ◽  
Segmental Motions

The effects of structural constraints on the main dielectric relaxation associated to segmental motions of polymer based materials are reviewed.

Dielectric Relaxation in Liquid Crystalline/Isotropic Block Copolymers:  Effect of Nanoscale Confinement on the Segmental Dynamics

2002 ◽  
Vol 35 (22) ◽  
pp. 8521-8530 ◽  
Author(s):  
Sergei Zhukov ◽  
Steffen Geppert ◽  
Bernd Stühn ◽  
Rosina Staneva ◽  
Rouja Ivanova ◽  
...  
Keyword(s):  
Block Copolymers ◽  
Dielectric Relaxation ◽  
Liquid Crystalline ◽  
Segmental Dynamics

scholarly journals Confinement Effects on The Local Motion in Nanocomposites

1998 ◽  
Vol 543 ◽  
Author(s):  
S. H. Anastasiadis ◽  
K. Karatasos ◽  
G. Vlachos ◽  
E. Manias ◽  
E. P. Giannelis
Keyword(s):  
Dielectric Relaxation ◽  
Interlayer Spacing ◽  
Dielectric Relaxation Spectroscopy ◽  
Local Motion ◽  
Relaxation Mode ◽  
Segmental Dynamics ◽  
Organically Modified Silicates ◽  
Organically Modified ◽  
Reorientational Dynamics ◽  
Methyl Phenyl

AbstractThe local segmental dynamics of polymers confined within the 15–20 Å interlayer spacing of nanocomposites consisting of poly(methyl phenyl siloxane) intercalated within organically modified silicates, has been investigated utilizing Dielectric Relaxation Spectroscopy. The effect of confinement on the local reorientational dynamics is evident by the observation of a relaxation mode, which is much faster than the segmental α-relaxation of the bulk polymer and exhibits much weaker temperature dependence. This is attributed to the restrictions placed by the interlayer spacing on the cooperative volume required for the ax-relaxation.

Dielectric Relaxation Studies of Silver Nanoparticles dispersed Liquid Crystal

2015 ◽  
Vol 8 (3) ◽  
pp. 2176-2188 ◽  
Author(s):  
Keisham Nanao Singh
Keyword(s):  
Activation Energy ◽  
Silver Nanoparticles ◽  
Liquid Crystal ◽  
Dielectric Relaxation ◽  
Relaxation Process ◽  
Relaxation Times ◽  
Low Frequency ◽  
Bulk Liquid ◽  
Molecular Rearrangement ◽  
Relaxation Studies

This article reports on the Dielectric Relaxation Studies of two Liquid Crystalline compounds - 7O.4 and 7O.6 - doped with dodecanethiol capped Silver Nanoparticles. The liquid crystal molecules are aligned homeotropically using CTAB. The low frequency relaxation process occurring above 1 MHz is fitted to Cole-Cole formula using the software Dielectric Spectra fit. The effect of the Silver Nanoparticles on the molecular dipole dynamics are discussed in terms of the fitted relaxation times, Cole-Cole distribution parameter and activation energy. The study indicate a local molecular rearrangement of the liquid crystal molecules without affecting the order of the bulk liquid crystal molecules but these local molecules surrounding the Silver Nanoparticles do not contribute to the relaxation process in the studied frequency range. The observed effect on activation energy suggests a change in interaction between the nanoparticles/liquid crystal molecules.

Dielectric Relaxation in Liquid Crystal Phases with Polar Order

2003 ◽  
Vol 297 (1) ◽  
pp. 91-105
Author(s):  
B. Żywucki ◽  
W. Kuczyński ◽  
J. Małecki
Keyword(s):  
Liquid Crystal ◽  
Dielectric Relaxation ◽  
Polar Order ◽  
Crystal Phases ◽  
Liquid Crystal Phases
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