Regensburg 2013 – scientific programme
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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 36: Poster: (Hydro)gels and Elastomers
CPP 36.1: Poster
Wednesday, March 13, 2013, 16:30–18:30, Poster C
The distribution of segmental order in polymer networks — •Michael Lang1 and Jens-Uwe Sommer1,2 — 1Leibniz Institut für Polymerforschung Dresden, Hohe Straße 6, 01069 Dresden — 2Institut für Theoretische Physik, Technische Universität Dresden, 01062 Dresden
We discuss the distribution function of the segment orientation order parameter in entangled networks. The distribution function is derived from a tube model of polymer entanglements assuming random walk statistics of the tube. Monomer fluctuations along the tube are assumed to follow the phantom model as shown in a previous work [M. Lang, J.-U. Sommer, Physical Review Letters 104 (2010) 177801]. The predictions are compared with simulation data of model networks that were created using the bond fluctuation method. The comparison reveals that local fluctuations of the tube statistics do not affect the distribution function as averaged over the full sample. Instead, length fluctuations of the confining tube control the shape of the distribution function. Furthermore, a narrowing of the distribution function is determined, if the cross-linking occurs on the time scale of the relaxation of the network strands. Almost instantaneously cross-linked polydisperse samples do not show this narrowing and are well described by tube length fluctuations that agree to previous work on the dynamics of melts of star polymers.