[1] Helmholtz Zentrum Geesthacht, Polymer Res Inst, D-21502 Geesthacht, Germany
[2] Chinese Acad Sci, Inst Chem, Joint Lab Polymer Sci & Mat, State Key Lab Polymer Phys & Chem, Beijing 100190, Peoples R China
[3] Chinese Acad Sci, Grad Sch, Beijing 100049, Peoples R China
[4] Univ Liege, CERM, B-4000 Liege, Belgium