1. Key Laboratory of Polymer EcomaterialsChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
2. University of Chinese Academy of Sciences Beijing 100039 P. R. China
3. Department of ChemistryNortheast Normal University Changchun 130022 P. R. China
4. Jilin Biomedical Polymers Engineering Laboratory Changchun 130022 P. R. China