A8 (N): Roberto - Improved dynamics in self-consistent field molecular dynamics simulations of polymers

The aim of this project is to develop a molecular simulation algorithm for chemically realistic polymers and nanocomposites that combines two recently developed methods:
(i) The so-called hybrid particle-field (hPF) method of Milano and coworkers,
(ii) The slip-spring concept as mock-up for entanglements,
which are difficult to capture in the hPF model due to the absence of hard core interactions. The method shall be analyzed in detail and the scientific risks will be carefully evaluated. It will be applied to study the dynamical and rheological properties of polymers and nanocomposites.

Funding for this project has started in July 2018

Atomistic hybrid particle‐field molecular dynamics combined with slip‐springs: Restoring entangled dynamics to simulations of polymer melts
Zhenghao Wu, Andreas Kalogirou, Antonio De Nicola, Giuseppe Milano, Florian Müller‐Plathe
Journal of Computational Chemistry, (2020);
doi:https://doi.org/10.1002/jcc.26428

↓ Show Abstract↑ Hide Abstract In hybrid particle‐field (hPF) simulations (J. Chem. Phys., 2009 130, 214106), the entangled dynamics of polymer melts is lost due to chain crossability. Chains cross, because the field‐treatment of the nonbonded interactions makes them effectively soft‐core. We introduce a multi‐chain slip‐spring model (J. Chem. Phys., 2013 138, 104907) into the hPF scheme to mimic the topological constraints of entanglements. The structure of the polymer chains is consistent with that of regular molecular dynamics simulations and is not affected by the introduction of slip‐springs. Although slight deviations are seen at short times, dynamical properties such as mean‐square displacements and reorientational relaxation times are in good agreement with traditional molecular dynamics simulations and theoretical predictions at long times.

Influence of Polymer Bidispersity on the Effective Particle–Particle Interactions in Polymer Nanocomposites
Gianmarco Munaò, Antonio De Nicola, Florian Müller-Plathe, Toshihiro Kawakatsu, Andreas Kalogirou, Giuseppe Milano
Macromolecules, (2019);
doi:10.1021/acs.macromol.9b01367

Contact

Prof. Dr. Florian Müller-Plathe
Institut für Physikalische Chemie
Technische Universität Darmstadt
Alarich-Weiss-Str. 8
D-64287 Darmstadt
Tel: +49 6151 16-22621
Fax: +49 6151 16-22619
f.mueller-plathexXJFMpKNFww@QOaXcnhcgvtheo.chemie.tu-darmstadt.de
http://www.chemie.tu-darmstadt.de/mueller-plathe/home/