Vogel-Fulcher dependence of relaxation rates in a nematic monomer and elastomer

Citation
D. Shenoy et al., Vogel-Fulcher dependence of relaxation rates in a nematic monomer and elastomer, PHYS REV E, 62(6), 2000, pp. 8100-8105
Citations number
41
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW E
ISSN journal
1063651X → ACNP
Volume
62
Issue
6
Year of publication
2000
Part
A
Pages
8100 - 8105
Database
ISI
SICI code
1063-651X(200012)62:6<8100:VDORRI>2.0.ZU;2-3
Abstract
Dielectric relaxation spectroscopy is used to study the relaxation processe s in a nematic monomer and the corresponding cross-linked polymer nematic l iquid crystal (elastomer). In the frequency window 10 mHz to 2 GHz the mono mer liquid crystal shows a single relaxation whereas the polymer exhibits t hree relaxation processes, two of which are quantitatively analyzed. The te mperature dependence of relaxation times in both the monomer and polymer fo llows a Vogel-Fulcher behavior. The relaxation processes are identified wit h specific molecular motions and activation energies are calculated in a li near approximation for comparison with literature data.