Berlin 2008 – wissenschaftliches Programm
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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 29: Polymerphysics I
CPP 29.8: Vortrag
Donnerstag, 28. Februar 2008, 11:30–11:45, C 130
SANS observation of the relaxation of a hyperbranched polymer in a linear matrix after a large step strain deformation — •Louisa Dahbi1, Wim Pyckhout-Hintzen1, Juergen Allgaier1, Dieter Richter1, Ekkehard Straube2, Nikos Hadjichristidis3, Hermis Iatrou3, and Melissa Sharp4 — 1Forschungszentrum Juelich, IFF, D-52425 Jülich, Germany — 2M-L University Halle, D-0 6122 Halle, Germany — 3University of Athens, Polymer Group, Greece — 4GKSS, IMR, D-21502 Geesthacht, Germany
The feasibility of well defined branched model polymer and the recent advances in the tube model theory gave rise to a better understanding of the dynamic and rheology of branched polymers. Our study aims to focus on the relaxation of a non-linearly stretched hyperbranched polymer blended with linear chains of different length, constituting the matrix, so as to study the effects of this latter on the time dependence of the relaxation process of the hyperbranched arms. The relaxation was investigated with quenched SANS experiments using our elongational stretching rheometer which decouples microscopic and laboratory time scales. Hyperbranched as well as linear polymers used for this study are constituted by polyisoprene. Both systems (short and long matrix) were submitted to identical relaxation times so as to quantify and conclude on the influence of the matrix length on the time dependence of the relaxation process of the hyperbranched arms. The relaxation of the short matrix taking place concurrently is expected to accelerate the relaxation of the hyperbranched itself. A link to a former work on linear polymer and well entangled H-shaped is presented.