Berlin 2008 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

CPP: Fachverband Chemische Physik und Polymerphysik

CPP 37: Molecular Dynamics

CPP 37.5: Vortrag

Freitag, 29. Februar 2008, 11:30–11:45, C 230

Disentanglement in thin polymer films — •Hendrik Meyer — Institut Charles Sadron, CNRS UPR22, Strasbourg, France

Molecular dynamics simulations of thin polymer films confined between structureless walls show accelerated in-plane dynamics with decreasing film thickness. Using the primitive path analysis (PPA) introduced by Everaers et al [Science 303 (2004) 823] for chain length up to N=1024, we can show that the entanglement density decreases with decreasing film thickness. However, the effect becomes pronounced only for films thinner than the bulk radius of gyration where also the structure of the chains becomes modified by the confinement [1]. The PPA algorithm can be modified to estimate the contribution of self-entanglements: The latter become more important for thinner films, however, they do not counterbalance the global decrease of entanglements.

[1] H. Meyer et al Eur. Phys. J. Sp.Top. 141 (2007) 167.