1. State Key Laboratory of Fine Chemicals, Department of Polymer Materials & Engineering, Liaoning Province Engineering Research Centre of High Performance Resins, Dalian University of Technology, Dalian 116024, P. R. China
2. School of Materials Science and Engineering, Key Laboratory of Energy Materials and Devices (Liaoning Province), State Key Laboratory of Fine Chemicals, Liaoning Province Engineering Centre of High Performance Resins, Dalian University of Technology, Dalian 116024, P. R. China
3. School of Mathematical Sciences, Dalian University of Technology, Dalian 116024, P. R. China