1. Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education College of Chemistry Xiangtan University Xiangtan 411105 P. R. China
2. College of Material Science & Engineering Guangxi Key Laboratory of Information Materials Guilin University of Electrical Technology Guilin 541004 P. R. China
3. Key Laboratory of Polymeric Materials & Application Technology of Hunan Province College of Chemistry Xiangtan University Xiangtan 411105 P. R. China