[1] Functional Materials Research Center, Korea Institute of Energy Research, Daejeon 305-343, Korea, Republic of
[2] Department of Textile Engineering, Chungnam National University, Daejeon 305-764, Korea, Republic of
[3] Polymer/Biocomposites Research Laboratory, Department of Polymer Science and Engineering, Kumoh National Institute of Technology, Gumi, Gyungbuk 730-701, Korea, Republic of