1. Max-Planck-Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany; Technical University of Berlin, Institute for Nonmetallic Materials, Polymer Physics, Englische Str. 20, 10587 Berlin, Germany; TU München, Physics Department LS E13, James-Franck-Str. 1, 85747 Garching, Germany; and Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany