Project A8: Roberto – Improved dynamics in hybrid particle-field molecular dynamics simulations of polymers

We pursue one of the approaches to generate coarse-grained polymer models with correct dynamical properties. If such models can be made predictive for, say, polymer melt viscosities and other rheological characteristics they will make their important contribution toward, e.g., energy-efficient plastics processing or mechanical recycling of plastics waste. In funding period 2 (FP2), we have developed and implemented the Roberto method, a combination of hybrid-particle-field (hPF) molecular dynamics and slip-springs. The hPF method by itself is computationally fast, yet it allows coarse-grained or even atomistic accuracy for the base models. It performs excellent for static polymer properties, but provides a qualitatively wrong molecular mobility. As the field treatment of intermolecular interactions makes them effectively soft-core, atoms can superpose, and polymer chains can cut through one another. The artificial dynamics is remedied by the slip-springs, which restore ntangled dynamics to the polymer chains. The Roberto method combination has been validated for atomistic and coarse-grained descriptions of melts of linear and branched polymers.

In funding period 3, Roberto is going to be extended to systems not covered so far, such as polymer mixtures, interfaces, nanocomposites and elastomers. The systems to be studied will, thus, move closer to actual applications in the field. We anticipate that Roberto will need adaptations to be able to handle the more complex systems. At the same time, we intend to improve the inner machinery of Roberto. Firstly, we will revisit the density functionals that lie at the heart of the hPF part of the description. Currently, they are based on a simple Flory-Huggins ansatz. We are going to replace them by numerical functionals tuned to reproduce interactions or forces of full pairwise calculations. Secondly, we will investigate whether the field part of hPF can be made to conserve local momentum (the slip-springs already do). This is a major undertaking but, if successful, will enable the calculation of rheological properties.

Mobility of polymer melts in a regular array of carbon nanotubes
S.A.N. Alberti, J. Schneider, and F. Müller-Plathe
J. Chem. Theor. Comput. 18, 3285–3295 (2022)
see publication

Boron-Modified Perhydropolysilazane Towards Facile and Economical Synthesis of Amorphous SiBN Ceramic with Excellent Thermal Stability
Y. Zhan, W. Li, T. Jiang, C. Fasel, E. Ricohermoso III, J. Bernauer, Z. Yu, Z. Wu, F. Müller-Plathe, L. Molina-Luna, R. Grottenmüller, and R. Riedel
J. Adv. Ceram. 11, 1104–1116 (2022)
see publication

Slip-Spring Hybrid Particle-Field Model for Coarse-Graining Branched Polymer Melts: Polystyrene Melts as an Example
Z. Wu and F. Müller-Plathe
J. Chem. Theor. Comput. 18, 3814–3828 (2022)
see publication

Roughness volumes: An improved RoughMob concept for predicting the increase of molecular mobility upon coarse-graining
M.K. Meinel and F. Müller-Plathe
J. Phys. Chem. B 126, 3737−3747 (2022)
see publication

Simulation of Elastomers by Slip-Spring Dissipative Particle Dynamics
J. Schneider, F. Fleck, H. A. Karimi-Varzaneh, F. Müller-Plathe
Macromolecules 54, 5155 (2021)
see publication

The Role of the Envelope Protein in the Stability of a Coronavirus Model Membrane against an Ethanolic Disinfectant
S. Das, M.K. Meinel, Z. Wu, F. Müller-Plathe
Journal of Chemical Physics, 245101 (2021)
see publication

Sequence-Engineering Polyethylene–Polypropylene Copolymers with High Thermal Conductivity Using a Molecular-Dynamics-Based Genetic Algorithm
Tianhang Zhou, Zhenghao Wu, Hari Krishna Chilukoti, Florian Müller-Plathe
Journal of Chemical Theory and Computation17 (6),3772-3782 (2021)
see publication

Combination of Hybrid Particle-Field Molecular Dynamics and Slip-Springs for the Efficient Simulation of Coarse-Grained Polymer Models: Static and Dynamic Properties of Polystyrene Melts
Zhenghao Wu, Giuseppe Milano, and Florian Müller-Plathe
Journal of Chemical Theory and Computation 17, 474–487 (2021)
see publication

Atomistic hybrid particle-field molecular dynamics combined with slip-springs: Restoring entangled dynamics to simulations of polymer melts
Z. Wu, A. Kalogirou, A. De Nicola, G. Milano, F. Müller-Plathe
Journal of Computational Chemistry 42, 6-18 (2021)
see publication

Knotting Behaviour of Polymer Chains in the Melt State for Soft-core Models with and without Slip-springs
Zhenghao Wu, Simon N. A. Alberti, Jurek Schneider, Florian Müller-Plathe
Journal of Physics: Condensed Matter, (2021)
see publication

Mechanisms of Nucleation and Solid−Solid-Phase Transitions in Triblock Janus Assemblies
Hossein Eslami, Ali Gharibi and Florian Müller-Plathe
Journal of Chemical Theory and Computation 17 (3), 1742−1754 (2021)
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Loss of Molecular Roughness upon Coarse-Graining Predicts the Artificially Accelerated Mobility of Coarse-Grained Molecular Simulation Models
M. K. Meinel, F. Müller-Plathe
Journal of Chemical Theory and Computation 16, 1411 (2020)
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Self-assembly mechanisms of triblock Janus particles
H. Eslami, N. Khanjari, F. Müller-Plathe
Journal of Chemical Theory and Computation 15, 1345–1354 (2019)
see publication

Gaussian charge distributions for incorporation of electrostatic interactions in dissipative particle dynamics: Application to self-assembly of surfactants
H. Eslami, M. Khani, F. Müller-Plathe
Journal of Chemical Theory and Computation 15, 4197−4207 (2019)
see publication

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 52, 8826-8839 (2019)
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Solid-Liquid and Solid-Solid Phase Diagrams of Self-Assembled Triblock Janus Nanoparticles from Solution
H. Eslami, K. Bahri, F. Müller-Plathe
The Journal of Physical Chemistry C122, 9235–9244 (2018)
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Local bond order parameters for accurate determination of crystal structures in two and three dimensions
H. Eslami, P. Sedaghat, and F. Müller-Plathe
Physical Chemistry Chemical Physics 20, 27059-27068 (2018)
see publication

Molecular Structure and Multi-Body Interactions in Silica-Polystyrene Nanocomposites
G. Munaò, A. Pizzirusso, A. Kalogirou, A. De Nicola, T. Kawakatsu, F. Müller-Plathe, G. Milano
Nanoscale 10, 21656–21670 (2018)
see publication