1. School of Chemistry Beihang University Beijing 100191 P. R. China
2. Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 P. R. China
3. State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Center for Advanced Low‐dimension Materials College of Materials Science and Engineering Donghua University Shanghai 201620 P. R. China
4. State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi'an 710049 P. R. China