1. Department of Materials, ETH Zurich, 8093 Zurich, Switzerland
2. Laboratory for Advanced Fibers, Empa Materials Science & Technology, 9014 St. Gallen, Switzerland
3. Civil & Environmental Engineering, University of Illinois at Urbana-Champaign, Illinois 61801, United States
4. Materials Science & Engineering, University of Illinois at Urbana-Champaign, Illinois 61801, United States