Advertise on podcast: Matière molle et biophysique - Jean-François Joanny

Jean-François Joanny Matière molle et biophysique Collège de France Année 2026-2027 Computational Soft Matter/Polymer Physics Conférence - Kurt Kremer: Stimuli Responsive Polymers: Co(non)-Solvency, Co-Solvency… Kurt Kremer Max Planck Institute for Polymer Research Résumé A material is referred to as stimuli responsive when a slight change in external parameters can drastically alter its structure, function, or stability. Polymers with their delicate entropy-energy interplay at ambient temperatures are especially suitable for such phenomena. Here, the example of polymer properties in solvent mixtures will be discussed. Special emphasis will be given to two prototypical phenomena: co-non-solvency and co-solvency. The first phenomenon is associated with the collapse of polymers in two miscible good solvents, where preferential solvation in one component is shown to trigger the collapse transition. The latter is associated with the swelling of polymers in mixtures of poor solvents, which is connected to depletion competition between different components.

Jean-François Joanny Matière molle et biophysique Collège de France Année 2026-2027 Computational Soft Matter/Polymer Physics Conférence - Kurt Kremer: Multiscale Modeling of Open Systems Kurt Kremer Max Planck Institute for Polymer Research Résumé As seen in the other lectures the relation between atomistic structure, architecture, molecular weight and material properties is of basic concern of modern soft matter science. Furthermore, when studying functional systems and in biology, one is faced with nonequilibrium and often driven systems, meaning that permanently energy is consumed and dissipated. Even nowadays it is almost impossible to simulate such systems at sufficient size and for long enough times on an all atom level. Here computer simulations on different levels of resolution play an important role and need to be connected. This is achieved by two different approaches, namely by sequential multiscale descriptions or adaptive schemes, which allow for a free exchange of particles (atoms, molecules) between the different levels of resolution. The latter is the topic of the present lecture. The methodology is introduced and it is shown how this can be applied to truly open, grand canonical simulations of molecular systems.

Jean-François Joanny Matière molle et biophysique Collège de France Année 2026-2027 Computational Soft Matter/Polymer Physics Conférence - Kurt Kremer: Some New Aspects of the Glass Transition in Simple Polymer Melts Kurt Kremer Max Planck Institute for Polymer Research Résumé The general physics of the glass transition is still a matter of intense research. Furthermore, many polymeric materials in practical use are in the glassy state. Glass formers are characterized as strong or fragile, meaning that the observed viscosity, while approaching the glass transition temperature, either follows the Arrhenius law (strong) or the KWW (Kohlrausch Williams Watts) law (fragile), the latter denoting a much stronger temperature dependency. The latter is important for many industrial production processes. Polymers are fragile glass formers and prototypical materials to investigate the glass transition. The deviation from the Arrhenius law is called fragility. In the lecture an adjusted model to study the glass transition of polymer melts will be introduced and applied. Furthermore, a new data driven method to identify first signals of approaching the glass transition upon cooling will be discussed.

Jean-François Joanny Matière molle et biophysique Collège de France Année 2026-2027 Computational Soft Matter/Polymer Physics Conférence - Kurt Kremer: Topology Effects: Playing with Entanglements to Structure Polymer Melts Kurt Kremer Max Planck Institute for Polymer Research Résumé The dynamics of dense polymer systems of long chains is governed by the fact that chains cannot cut through each other during their diffusive motion. These (temporary) topological constraints create what is called entanglements and dominate the rheological properties of long chain polymer melts and dense solutions. They lead to the well established reptation/tube model, which is at the basis of our understanding of many physical properties and technical processes. While in most technology related investigations entanglements are seen as a problem to deal with, one also can systematically employ them to manipulate and structure materials, either by avoiding or explicitly using/introducing entanglements. The lecture will give a few such examples, which range from non-entangled to highly entangled polymer systems and to new entanglement stabilized nanoporous films or topological glasses in active systems.

Jean-François Joanny Matière molle et biophysique Collège de France Année 2025-2026 06 - Transport dans la cellule : Dynamique des endosomes

Jean-François Joanny Matière molle et biophysique Collège de France Année 2025-2026 Patricia Bassereau Institut Curie Paris Séminaire - Patricia Bassereau : Membrane Trafficking in a Test Tube

Jean-François Joanny Matière molle et biophysique Collège de France Année 2025-2026 05 - Transport dans la cellule : Appareil de Golgi

Jean-François Joanny Chaire Chaire Matière molle et biophysique Collège de France Année 2025-2026 Pierre Sens Institut Curie Paris Séminaire - Pierre Sens : Modelling Self-Organisation and Transport in Cellular Organelles with Non-Equilibrium Dynamics

Jean-François Joanny Matière molle et biophysique Collège de France Année 2025-2026 04 - Transport dans la cellule : Réticulum endoplasmique

Jean-François Joanny Matière molle et biophysique Collège de France Année 2025-2026 Bruno Goud Institut Curie Paris Séminaire - Bruno Goud : Régulation de la voie de sécrétion par les GTPases

Jean-François Joanny Matière molle et biophysique Collège de France Année 2025-2026 03 - Transport dans la cellule : Transport actif : moteurs moléculaires

Jean-François Joanny Matière molle et biophysique Collège de France Année 2025-2026 Raphael Voituriez Institut Jean Perrin, Sorbonne Université Paris Séminaire - Raphael Voituriez : Anomalous and Non-Markovian Reaction Kinetics in Cells

Jean-François Joanny Matière molle et biophysique Collège de France Année 2025-2026 02 - Transport dans la cellule : Diffusion dans la cellule

Jean-François Joanny Matière molle et biophysique Collège de France Année 2025-2026 Marino Zerial Human Technopole, Milan Séminaire - Marino Zerial : Molecular Mechanisms of Endocytic Transport in Cell and Tissue Organization

Jean-François Joanny Matière molle et biophysique Collège de France Année 2025-2026 01 - Transport dans la cellule : Mécanismes de transport dans une cellule