Multiscale Simulations of Polymer Dynamics

The ultimate goal of this project is the creation and development of a rational design protocol for bionanocomposite materials based on chemically modified cellulose. This involves: i) development of a predictive integrated multiscale simulation protocol for the design of such materials, ii) verifying its foundations against analytical theory and experimental studies, and iii) collaboration with the Institute of Macromolecular Compounds (IMC) of Russian Academy of Sciences (RAS) which implements the computer-aided new design platform. This integrated approach provides a novel, innovative, and scalable platform for optimization and development of biodegradable and biocompatible polymer materials with chemically-modified surfaces, in particular bionanocomposites, for high-tech ecologically safe industrial and biomedical applications.

We contribute to a fully predictive multiphysics computational approach to the functioning of Organic Photovoltaic Cells (OPVC). This requires completing the knowledge about the functioning of OPVCs by obtaining a detailed understanding of the atomic-scale morphology and electronic processes at the Donor-Acceptor interface and linking this to larger scales. An important idea is that, next to the pure polymer and fullerene phases, there is a finely intermixed polymer/fullerene phase – called the mixed phase –  that is essential for efficient functioning of the OPVC . It is thought that in this mixed phase polymer chains connected to the polymer crystallites penetrate the fullerene network; see Figure on the left. Excitons created by light in the pure polymer phase diffuse to the mixed phase, where they have a somewhat lower energy, and then separate into free charges. The polymer chains that stick out into the fullerene network are supposed to quickly transfer the holes along their backbone to the crystalline polymer phase, where they delocalize, while the electrons move into the pure fullerene phase by the good electronic contact between the fullerenes. By the unique combination of a morphological and electronic-structure study we are able to create breakthroughs in the understanding of the charge-separation process. Such study is unique in its character and critical in completing the knowledge chain of the functioning of OPVCs. We give answers to the many questions around the ‘hot-exciton’ and ‘mixed-phase’ ideas by providing unbiased explicit calculations.

MSc project: Molecular dynamics simulations on polymeric vesicles

We always have a number of other very exciting opportunities for Master and Bachelor students. Also, we can help you identify possibilities for internships abroad, including Stanford University and San Diego State University. Possible research projects, to name but a few:

• morphologies of organic solar cells
• upscalled modelling of proton-exchange membranes for flow batteries
• understanding the glass transition in polymer thin films
• mechanics and segmental dynamics in polymer nanocomposites
• novel phase-change and thermo-chemical materials for thermal energy storage

The courses offered within the group are:

• 3FFX0     Statistical physics (Mede-docent)
• 3FMX0    Physical modelling and simulating (Mede-docent)
• 3MA010 Computational and mathematical physics (Verantw. Docent)
• 3MN100 Polymer physics (Mede-docent)
• 3MN200 Computational Materials Science (Mede-docent)
• 3NAB0    Applied Physical Sciences conceptual (Instructeur)
• 3MT120  Advanced Computational Fluid and Plasma Dynamics (Mede-docent)

The project aims to study, using computer modelling, the mechanical properties of elastomer-based nanocomposites for the applications in the automotive industry (production of car tires, Michelin) and as sealants (SKF). Usually, in these materials inorganic nanoparticles (Carbon Black, silica), commonly referred to as fillers, are added to rubber in order to increase its rigidity at low strain magnitudes. Nonlinear phenomena restrain the performance of the resulting composites and the development of possible new applications. The goal of the project is to connect the viscoelastic properties of the elastomer-based composites with their microstructure, and the microstructure with the adhesion polymer-filler interactions at the segmental scale. Control of these interactions will lead to the design of new materials with tailored specific mechanical properties. We investigate, using fully-atomistic and coarse-grained molecular-dynamics computer simulations, the equilibrium structure and the dynamics of the composite constituent parts, as well as their mechanical properties under the influence of the oscillatory shear, on different scales.