1. School of Materials Science & Engineering, Zhengzhou University, Zhengzhou 450002, People’s Republic of China
2. Hermann Staudinger Graduate
School, University of Freiburg, D-79104
Freiburg, Germany
3. National Engineering Research Center
for Advanced Polymer Processing Technologies, Zhengzhou University, Zhengzhou 450002, People’s Republic
of China
4. Institute of Physics, University of Freiburg, D-79104 Freiburg, Germany