1. a Department of Macromolecular Science , Case Western Reserve University Cleveland , Ohio, 44106
2. b Mitsubishi Chemical Industries, Ltd. , 1000-Kamoshide-Cho Midori-Ku, Yokahama-City, Kanagawa, Japan
3. c Polymer Group, Department of Metallurgy and Mining Engineering , University of Illinois , Urbana, Illinois, 61801