Affiliation: | 1. Department of Chemical Technology , Seoul National University , Seoul, 151-742, Korea;2. Department of Chemical Technology , Seoul National University , Seoul, 151-742, Korea;3. Polymer Laboratory III , Taedok Institute of Technology, Yukong Ltd. , Daejeon, 305-370, Korea;4. Department of Chemistry , University of Ulsan , Ulsan, 680-749, Korea |