1. Institute of Special Materials and Technology, Fudan University, Shanghai, P. R. China.
2. Department of Materials Science, Fudan University, Shanghai, P. R. China.
3. State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai, P. R. China.
4. State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai, PR China.
5. Department of Mechanical Engineering, George Mason University, Fairfax, VA 22030, USA.