Correlated heterogeneous dynamics in glass-forming polymers

Conrad, H.; Lehmkühler, F.; Fischer, B.; Westermeier, Fabian; Schroer, M. A.; Chushkin, Y.; Gutt, C.; Sprung, M.; Grübel, G.

doi:10.1103/PhysRevE.91.042309

Item

ITEM ACTIONSEXPORT

Add to Basket

Local TagsRelease HistoryDetailsSummary

Released

Journal Article

Correlated heterogeneous dynamics in glass-forming polymers

MPS-Authors

/persons/resource/persons188182

Westermeier, Fabian
Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany;
Miller Group, Atomically Resolved Dynamics Department, Max Planck Institute for the Structure and Dynamics of Matter, Max Planck Society;

External Resource

http://dx.doi.org/10.1103/PhysRevE.91.042309
(Publisher version)

Fulltext (restricted access)

There are currently no full texts shared for your IP range.

Fulltext (public)

PhysRevE.91.042309.pdf
(Publisher version), 595KB

Supplementary Material (public)

There is no public supplementary material available

Citation

Conrad, H., Lehmkühler, F., Fischer, B., Westermeier, F., Schroer, M. A., Chushkin, Y., et al. (2015). Correlated heterogeneous dynamics in glass-forming polymers. Physical Review E, 91(4): 042309. doi:10.1103/PhysRevE.91.042309.

Cite as: https://hdl.handle.net/11858/00-001M-0000-002A-3B57-F

Abstract

We report x-ray photon correlation spectroscopy experiments on the dynamics of the glass-former polypropylene glycol covering a temperature range from room temperature to the glass transition at T_g = 205 K using silica tracer particles. Three temperature regimes are identified: At high temperatures, Brownian motion of the tracer particles is observed. Near T_g, the dynamics is hyperdiffusive and ballistic. Around 1.12T_g, we observe an intermediate regime. Here the stretching exponent of the Kohlrausch-Williams-Watts function becomes q dependent. By analyzing higher-order correlations in the scattering data, we find that dynamical heterogeneities dramatically increase in this intermediate-temperature regime. This leads to two effects: increasing heterogeneous dynamics and correlated motion at temperatures close to and below 1.12T_g.