1. Department of Polymer Engineering, University of Akron, Akron, Ohio 44325, USA
2. Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
3. Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204, USA
4. Department of Chemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
5. Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA