DOI: 10.1209/epl/i2002-00651-7


Europhys. Lett., 58 (3) , pp. 389-394 (2002)

Direct observation of domain wall excitations in symmetric diblock copolymer melts at and above the order-disorder transition

H. Montes¹, M. Monkenbusch², L. Willner², S. Rathgeber², D. Richter², L. J. Fetters³ and B. Farago<sup>4

1</sup>  ESPCI, Physico-chimie Structurale et Macromoleculaire 10 rue Vauquelin, F-75005 Paris Cedex, France
²  Institut für Festkörperforschung, Forschungszentrum Jülich D-52425 Jülich, Germany
³  School of Chemical Engineering, Olin Hall, Cornell University Ithaca, NY 14850, USA
⁴  Institut Laue-Langevin - B.P. 156X, Avenue des Martyrs F-38042 Grenoble Cedex 9, France

(Received 15 February 2001; accepted in final form 11 February 2002)

Abstract
The dynamics of the chain junctions in a lamellar diblock copolymer melt around the order-disorder transition temperature (ODT) has been investigated by neutron spin echo (NSE) spectroscopy, utilizing deuterated diblock copolymers with a hydrogen-labeled section at the junction point. We observed a dynamic response which was more than one order of magnitude faster than expected from standard Rouse dynamics. The corresponding driving force was shown to relate to interfacial tension implying the existence of interfacial walls near the ODT.

PACS
61.12.-q - Neutron diffraction and scattering.
47.50.+d - Non-Newtonian fluid flows.
83.80.Hj - Suspensions, dispersions, pastes, slurries, colloids.


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