1. Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
2. Mechanical Engineering Department, University of Michigan, Ann Arbor, Michigan 48109, United States
3. Walker Department of Mechanical Engineering, Texas Materials Institute, and Oden Institute for Computational Engineering and Sciences, University of Texas at Austin, 204 East Dean Keeton Street, ETC II 5.160, Austin, Texas 78712-1591, United States
4. Macromolecular Science and Engineering Program, University of Michigan, Ann Arbor, Michigan 48109, United States