1. Key Laboratory of Polymer EcomaterialsChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
2. University of Science and Technology of China Hefei 230026 P. R. China
3. Jilin Biomedical Polymers Engineering Laboratory Changchun 130022 P. R. China
4. College of ChemistryJilin University Changchun 130012 P. R. China