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CPP: Fachverband Chemische Physik und Polymerphysik

CPP 23: Polymer Dynamics

CPP 23.1: Hauptvortrag

Mittwoch, 13. März 2013, 09:30–10:00, H39

Polymers, rings and pores: A neutron scattering study — •Andreas Wischnewski — Jülich Centre for Neutron Science JCNS-1 and Institut for Complex Systems ICS-1, Forschungszentrum Jülich, Germany

Polymers are one of the most important and fascinating soft matter materials both from the fundamental point of view as well as with respect to their wide range of applications. Industrial processing, design, fabrication and application depends to a large extend on the understanding of the rheological properties on a microscopic level. Neutron scattering is a powerful tool to access the microscopic characteristics of polymeric systems and has already significantly contributed to the understanding of the static and dynamic properties of polymers with different architectures and in different, complex environments. Recently, ring polymers have attracted ample interest both from simulation experts and experimentalists. The absence of chain ends, which determine the dynamics of linear chains and in particular branched polymers, allows to examine fundamental aspects of polymer theory. Neutron spin echo spectroscopy reveals significant differences in ring dynamics compared to the linear counterpart. In particular rings cannot build up easily the tube confinement as known from long linear chains. In contrast to that, polymers in nano-pores are subject to a stronger topological confinement as compared to the bulk system if a surface-polymer interaction is present. Neutron scattering studies combined with complementary techniques are presented.