The deuteron NMR Hahn echo decay in polyethylene oxide melts

The deuteron transverse relaxation properties of polyethylene oxide melts of four different molecular weights, covering the range from the onset of entanglements to the regime of fully entangled chains, are investigated using Hahn echo decays over an extensive time interval up to ten times the effec...

Full description

Saved in:
Bibliographic Details
Published in:AIP advances 2022-07, Vol.12 (7), p.075219-075219-12
Main Authors: Lindt, K., Mattea, C., Stapf, S., Ostrovskaya, I. K., Fatkullin, N. F.
Format: Article
Language:English
Subjects:
Chain entanglement
Decay
Deuterons
Heterogeneity
Melts
Molecular weight
NMR
Nuclear magnetic resonance
Polyethylene
Polyethylene oxide
Relaxation time
Reptation
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The deuteron transverse relaxation properties of polyethylene oxide melts of four different molecular weights, covering the range from the onset of entanglements to the regime of fully entangled chains, are investigated using Hahn echo decays over an extensive time interval up to ten times the effective transverse spin relaxation time. The results are compared to predictions based on the Rouse and reptation formalisms, taking into account the dynamical heterogeneity of linear polymer chains produced by the end segments. The experimental results can be described qualitatively by a combination of both models, with the contribution of reptation dynamics increasing with growing chain length. The transition is continuous, rather than being characterized by sharp regime boundaries. Up to a molecular weight of 300.000 g/mol, the predicted limit of pure reptation dynamics is not yet reached. Quantitative deviations from the predicted decays as computed by numerical procedures become observable toward the long-time limit of the Hahn echo decays and are being discussed in terms of shortcomings of the available reptation theories.
ISSN:2158-3226
2158-3226
DOI:10.1063/5.0099293