1. Key Laboratory of Carbon Fibers and Functional PolymersMinistry of EducationBeijing Engineering Research Center for the Synthesis and Applications of Waterborne Polymers and College of Materials Science and EngineeringBeijing University of Chemical Technology Beijing 100029 P. R. China
2. State Key Laboratory of Chemical Resource Engineering and College of Materials Science and EngineeringBeijing University of Chemical Technology Beijing 100029 China