1. Hebei Key Laboratory of Functional Polymers Department of Polymer Materials and Engineering School of Chemical Engineering and Technology Hebei University of Technology 8 Guangrong Street Tianjin 300130 P. R. China
2. Downhole Technology Service Company Bohai Drilling Engineering Company Limited, CNPC Dagang, Tianjin 300283 P. R. China
3. College of Science Civil Aviation University of China Tianjin 300300 P. R. China
4. School of Science Nantong University Nantong 226019 Jiangsu Province P. R. China