1. Max Planck Institute for Polymer Research, P.O. 3148, 55128 Mainz, Germany; Department of Materials Science and Technology, University of Crete, and FORTH, P.O. 1527, 71110 Heraklion, Greece; Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139; and Institute for Soldier Nanotechnologies, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139