Copolymerization of ethylene and 1-hexene with TiCl4/MgCl2 catalysts modified by 2,6-diisopropylphenol |
| |
Authors: | Sheng-jie Xia Zhi-sheng Fu Xiao-yan Liu Zhi-qiang Fan |
| |
Institution: | MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering,Zhejiang University, Hangzhou 310027, China |
| |
Abstract: | A supported TiCl4/MgCl2 catalyst without internal electron donor (O-cat) was prepared firstly. Then it was modified by 2,6-diisopropylphenol to make a novel modified catalyst (M-cat). These two catalysts were used to catalyze ethylene/1-hexene copolymerization and 1-hexene homopolymerization. The influence of cocatalyst and hydrogen on the catalytic behavior of these two catalysts was investigated. In ethylene/1-hexene copolymerization, the introduction of 2,6- i Pr2C6H3O- groups did not deactivate the supported TiCl4/MgCl2 catalyst. Although the 1-hexene incorporation in ethylene/1-hexene copolymer prepared by M-cat was lower than that prepared by O-cat, the composition distribution of the former was narrower than that of the latter. Methylaluminoxane (MAO) was a more effective activator for M-cat than triisobutylaluminium (TIBA). MAO led to higher yield and more uniform chain structure. In 1-hexene homopolymerization, the presence of 2,6- i Pr2C6H3O- groups lowered the propagation rate constants. Two types of active centers with a chemically bonded 2,6- i Pr2C6H3O- group were proposed to explain the observed phenomena in M-cat. |
| |
Keywords: | Supported Ziegler-Natta catalyst 2 6-Diisopropylphenol Ethylene copolymerization Active center distribution |
本文献已被 CNKI 万方数据 SpringerLink 等数据库收录! |
| 点击此处可从《高分子科学》浏览原始摘要信息 |
| 点击此处可从《高分子科学》下载免费的PDF全文 |
|