Dresden 2003 – wissenschaftliches Programm
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SYSE: Simulation and experiment
SYSE 1: Simulation and experiment - spanning the bridge between microscopic and macroscopic scales
SYSE 1.4: Hauptvortrag
Dienstag, 25. März 2003, 12:30–13:00, ZEU/160
Simulation of Polymer Crystallization — •Hendrik Meyer — Institut Charles Sadron, CNRS, 67083 Strasbourg, France
Semicrystalline polymer structures contain lamellar crystal domains which are in the order of 10nm thick. The crystallization process is still not completely understood. Its simulation from the disordered melt is a difficult task because a large number of particles have to be considered and a long period of time is needed. However, lamellar-like structures could be obtained with classical MD simulations starting from the melt using a simplified model [1]. It fits well to polyethylene and consists of beads containing 2 carbon atoms. An angle-bending potential represents the torsional states of the atomistic chain. This model shows realistic chain-length and temperature dependences. Crystallization and melting lines could be determined as in isothermal crystallization experiments. Since the model contains no explicite attraction between monomers, the conformational statistics and the packing are sufficient driving forces for the crystallization. The simulations have now been extended to larger boxes with chain length N=400 (C800) which give further insights into the structure formation process [2].
[1] H. Meyer and F. Müller-Plathe, J. Chem. Phys. 115 (2001) 7807; Macromolecules 35 (2002) 1241.
[2] H. Meyer in Lect. Notes in Phys. J.U. Sommer, G. Reiter (eds.) in press.