1. Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
2. Dipartimento di Fisica, CSMFO Group, Università di Trento, Via Sommarive 14, 38100 Trento, Italy
3. Deutsches Kunststoff-Institut, Schlossgartenstr. 6, 64289 Darmstadt, Germany
4. Department of Materials Science, University of Crete and FORTH, 71110 Heraklion, Greece