1. College of Science Sichuan Agricultural University Ya'an 625014 P. R. China
2. College of Chemistry and Chemical Engineering Qingdao University Qingdao 266071 P. R. China
3. School of Materials Science and Engineering Hubei University of Automotive Technology Shiyan 442002 P. R. China
4. Institute of Materials for Energy and Environment State Key Laboratory of Bio‐fibers and Eco‐textiles College of Materials Science and Engineering Qingdao University Qingdao 266071 P. R. China