J. Phys. IV France 10 (2000) Pr7-239-Pr7-242
Molecular dynamics of supercooled polymer filmsF. Varnik1, J. Baschnagel2 and K. Binder1
1 Institut für Physik, Johannes-Gutenberg Universität, 55099 Mainz, Germany
2 Institut Charles Sadron, 6 rue Boussingault, 67083 Strasbourg, France
We present results of molecular dynamics simulations for a supercooled polymer melt confined between two smooth and purely repulsive walls. The thickness D of the film is about 7 times the bulk radius of gyration. For all temperatures studied, a significant increase of the monomer and chain mobilities with respect to the bulk is observed. Preliminary results suggest that structural relaxation times exhibit a power-law behavior in the vicinity of a critical temperature Tc(D) ≈ 0.39 (in Lennard-Jones units). This estimate of Tc(D) is about 14% smaller than the corresponding bulk value. Despite this significant decrease the time dependence of various mean-square displacements seems to be unaffected by confinement if data for the same reduced temperatures T - Tc of the bulk and the film are compared.
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