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CRYSTAF Analysis of Polyethylene Synthesized with Phillips Catalyst |
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| Authors: | Wei Xia Toshiaki Taniike Minoru Terano Tadahiro Fujitani Boping Liu João B P Soares |
| Institution: | 1. School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan
Research Institute for Innovation in Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba West 16-1 Onogawa, Tsukuba, Ibaraki, 305-8569, Japan;2. School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan;3. Research Institute for Innovation in Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba West 16-1 Onogawa, Tsukuba, Ibaraki, 305-8569, Japan;4. State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Mei Long Road 130, Shanghai, P. R. China, 200237;5. Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada N2L 3G1 |
| Abstract: | Crystallization analysis fractionation (CRYSTAF) was used for the first time to investigate the solution crystallization behavior of ethylene homopolymers and copolymers made with Phillips CrOx/SiO2 catalyst. Interestingly, the crystallization peak temperatures (Tp) of copolymers of ethylene and cyclopentene increased with increasing cyclopentene molar fraction in the copolymer. Comparing two factors (short chain branches (SCBs) and cyclopentene incorporation), decreasing SCB frequency is proposed as the dominant factor to explain the increase of crystallization peak temperatures with increasing cyclopentene incorporation. In addition, SCB frequency and molecular weight might be the two significant factors determining the crystallization temperature of polyethylene made with Phillips CrOx/SiO2 catalyst with different cocatalysts (triethylaluminum and diethylaluminum ethoxide). |
| Keywords: | comonomer crystallization analysis fraction (CRYSTAF) Phillips catalyst polyethylene (PE) short chain branches |