Organisers

• Florian Mueller-Plathe (Technical University of Darmstadt)
• Igal Szleifer (Dept. of Chemistry, Purdue University)
• Sylvie Neyertz (LMOPS - UMR CNRS 5041 - University of Savoie)
• David Brown (LMOPS - UMR CNRS 5041 - University of Savoie)

Supports

 CECAM

 COST - MolSimu

Description

Aim of the Workshop

The workshop will discuss the physics and chemistry of surfaces and interfaces of polymers, e.g.: polymer-vacuum, polymer-fluid, polymer-polymer, polymer-metal, polymer-ceramic, polymer-glass.

The workshop will bring together
• Polymer models of different length and time scales applied to the problem of polymer interfaces. The strengths and weaknesses of recent approaches will be reviewed. In addition, ways will be sought to connect models of different scale (scale-bridging, multiscaling) and to discuss their range of application.
• Particle-based polymer models often used in simulation and field-based models often used in analytical theory. The workshop will discuss how simulations can generate input for analytical models and theories and how the analytical concepts can be used to analyse and guide the simulations.
• Experiment and theory/simulation of polymer interfaces. Advances in experimental techniques will be presented and the quality of the data obtained will be assessed. The workshop will discuss which experimental data can be usefully employed to gauge simulations and theory and which theoretical informations and concepts can be used to interpret experiments.

The workshop will help the mutual appreciation of techniques, lead to cross-fertilisation between the fields, and hopefully contribute to the development of new concepts and methods for the study of polymer interfaces. Indirectly and in the very long term, this might even lead to better composites, nanomaterials or functional materials.

Scientific Objectives

Motivations and Objectives

Polymer surfaces and interfaces have an important role in many technical applications and in many biological phenomena. The surface of a polymeric material determines properties such as appearance, compatibility and chemical and mechanical stability. Hidden interfaces between polymers and other materials are crucial in applications like adhesives, coatings, filled polymers, or (nano)composites. Polymer-polymer interfaces largely determine the morphology and integrity of polymer blends and block-copolymer systems.

In many of these areas, successful simulations have been impeded by the lack of reasonable molecular structures of the polymer surface or interface, for example to be used as starting structures for molecular simulations. At the same time, it is not always clear by which criteria to define a surface structure as “good”, to which experimental data to compare. Experimental guidance is weak, because there is no experiment that can resolve a three-dimensional structure of an interface on the atomic scale. High-resolution experiments such as atomic-force microscopy only reveal the first layer of atoms (no depth information), diffraction techniques provide a good depth resolution, but at the price of averaging over a large area (no lateral information).

Nonetheless, progress has been made in the description of polymer surfaces and interfaces by simulation, by analytical theory and by advances in experimental techniques. It is the purpose of the workshop to bring together researchers from the three areas, to outline ways of how a better understanding of polymer interfaces by the various techniques can be achieved.

References

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