Regensburg 2019 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

CPP: Fachverband Chemische Physik und Polymerphysik

CPP 67: Polymer and Molecular Dynamics, Friction and Rheology

CPP 67.2: Vortrag

Freitag, 5. April 2019, 10:00–10:15, H13

Non-monotonic particle size effect on the glass transition in polymer-particle blends and its application to shape memory polymers — Elias M. Zirdehi and •Fathollah Varnik — ICAMS, Ruhr-Universität Bochum, Germany

The addition of small molecules is found to enhance the dynamics of structural relaxation in polymers and glasses [1]. This effect turns out to be a non-monotonic function of the particle size [2]. Through a detailed analysis of the non-Gaussian parameter for the particles and monomers, it is shown that the time scales of cooperative motion for the two constituents exhibit a separation when decreasing the size of particles. This decoupling of dynamics is also apparent in the ratio of diffusion coefficient and relaxation times of two species. Loss of the coupling effect makes the monomers become weakly influenced by the fast dynamics of the smaller particles. On the other hand, the larger particles are strongly coupled to polymers while being less mobile, which leads to a rather weak enhancement effect on the polymers dynamics. The strongest effect on polymers dynamics is observed in the intermediate particle sizes where the particles have high mobility as well as sufficiently strong coupling to the polymer matrix. A potential application of this effect can be the tuning of the triggering temperature in shape memory polymers. This issue is also briefly discussed.

1. Elias Mahmoudinezhad, Axel Marquardt, Gunther Eggeler and Fathollah Varnik, Procedia Computer Science 108, 265-271 (2017).

2. Elias M. Zirdehi, Fathollah Varnik, Non-monotonic particle size effect on the glass transition in polymer-particle blends (under rev.).