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Title: Polymer Chain Dynamics in a Random Environment: Heterogeneous Mobilities

Abstract

We present a neutron scattering investigation on a miscible blend of two polymers with greatly different glass-transition temperatures T{sub g}. Under such conditions, the nearly frozen high-T{sub g} component imposes a random environment on the mobile chain. The results demand the consideration of a distribution of heterogeneous mobilities in the material and demonstrate that the larger scale dynamics of the fast component is not determined by the average local environment alone. This distribution of mobilities can be mapped quantitatively on the spectrum of local relaxation rates measured at high momentum transfers.

Authors:
; ; ; ; ;  [1];  [2];  [3];  [4];  [3];  [5]
  1. Institut fuer Festkoerperforschung, Forschungszentrum Juelich, 52425 Juelich (Germany)
  2. (Germany)
  3. Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastian (Spain)
  4. Centro de Fisica de Materiales CSIC-UPV/EHU, Apartado 1072, 20080 San Sebastian (Spain)
  5. (Spain)
Publication Date:
OSTI Identifier:
20951262
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 16; Other Information: DOI: 10.1103/PhysRevLett.98.168301; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; GLASS; MOBILITY; MOMENTUM TRANSFER; NEUTRON DIFFRACTION; POLYMERS; RANDOMNESS; RELAXATION; TRANSITION TEMPERATURE

Citation Formats

Niedzwiedz, K., Wischnewski, A., Monkenbusch, M., Richter, D., Strauch, M., Straube, E., Fachbereich Physik, Martin-Luther-Universitaet Halle-Wittenberg, D-06099 Halle, Genix, A.-C., Arbe, A., Colmenero, J., and Centro de Fisica de Materiales CSIC-UPV/EHU, Apartado 1072, 20080 San Sebastian. Polymer Chain Dynamics in a Random Environment: Heterogeneous Mobilities. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.168301.
Niedzwiedz, K., Wischnewski, A., Monkenbusch, M., Richter, D., Strauch, M., Straube, E., Fachbereich Physik, Martin-Luther-Universitaet Halle-Wittenberg, D-06099 Halle, Genix, A.-C., Arbe, A., Colmenero, J., & Centro de Fisica de Materiales CSIC-UPV/EHU, Apartado 1072, 20080 San Sebastian. Polymer Chain Dynamics in a Random Environment: Heterogeneous Mobilities. United States. doi:10.1103/PHYSREVLETT.98.168301.
Niedzwiedz, K., Wischnewski, A., Monkenbusch, M., Richter, D., Strauch, M., Straube, E., Fachbereich Physik, Martin-Luther-Universitaet Halle-Wittenberg, D-06099 Halle, Genix, A.-C., Arbe, A., Colmenero, J., and Centro de Fisica de Materiales CSIC-UPV/EHU, Apartado 1072, 20080 San Sebastian. Fri . "Polymer Chain Dynamics in a Random Environment: Heterogeneous Mobilities". United States. doi:10.1103/PHYSREVLETT.98.168301.
@article{osti_20951262,
title = {Polymer Chain Dynamics in a Random Environment: Heterogeneous Mobilities},
author = {Niedzwiedz, K. and Wischnewski, A. and Monkenbusch, M. and Richter, D. and Strauch, M. and Straube, E. and Fachbereich Physik, Martin-Luther-Universitaet Halle-Wittenberg, D-06099 Halle and Genix, A.-C. and Arbe, A. and Colmenero, J. and Centro de Fisica de Materiales CSIC-UPV/EHU, Apartado 1072, 20080 San Sebastian},
abstractNote = {We present a neutron scattering investigation on a miscible blend of two polymers with greatly different glass-transition temperatures T{sub g}. Under such conditions, the nearly frozen high-T{sub g} component imposes a random environment on the mobile chain. The results demand the consideration of a distribution of heterogeneous mobilities in the material and demonstrate that the larger scale dynamics of the fast component is not determined by the average local environment alone. This distribution of mobilities can be mapped quantitatively on the spectrum of local relaxation rates measured at high momentum transfers.},
doi = {10.1103/PHYSREVLETT.98.168301},
journal = {Physical Review Letters},
number = 16,
volume = 98,
place = {United States},
year = {Fri Apr 20 00:00:00 EDT 2007},
month = {Fri Apr 20 00:00:00 EDT 2007}
}
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  • No abstract prepared.