许胜.负载双核茂金属催化剂催化乙烯聚合反应动力学研究[J].分子催化,2012,(6):537-545
负载双核茂金属催化剂催化乙烯聚合反应动力学研究
Study on Kinetics of Ethylene Polymerization Catalyzed by Supported Binuclear Metallocene
投稿时间:2012-08-24  修订日期:2012-11-26
DOI:
中文关键词:  乙烯聚合  动力学  负载双中心茂金属
英文关键词:kinetics  ethylene polymerization  supported binuclear metallocene
基金项目:双中心单组份催化剂合成热塑性弹性体研究(批准号 U1162111);国家自然科学基金项目(面上项目,重点项目,重大项目)
作者单位E-mail
许胜* 华东理工大学材料与工程学院 xusheng@ecust.edu.cn 
摘要点击次数: 2059
全文下载次数: 1971
中文摘要:
      以SiO2为载体,制备了负载的双核茂金属[(η5-C5H5) Zr Cl2]2[μ, μ-(SiMe2)2 (η5- allyl C5H2)2] /MAO/ SiO2催化剂,以己烷为溶剂进行了淤浆条件下乙烯聚合反应,研究了扩散因素、乙烯聚合压力和聚合温度对乙烯淤浆聚合动力学参数的影响,测定了聚合反应级数和表观活化能,采用动力学和相对分子质量法计算了负载催化剂的活性中心浓度,并对链增长速率常数等动力学参数进行了计算。结果表明,以负载双核茂金属催化剂催化乙烯淤浆聚合反应速率对单体浓度呈1.11级依赖,反应活化能Ea为72.47 kJ/mol,活性中心浓度C*为0.33 mol/mol,链增长速率常数Kp为1.06×106 L•(mol•h)-1。
英文摘要:
      The kinetics of ethylene polymerization catalyzed by supported binuclear metallocene catalyst [(η5-C5H5) ZrCl2]2[μ, μ-(SiMe2)2 (η5-allyl C5H2)2]/MAO/SiO2 in slurry phase was investigated. The effects of polymerization factors, such as diffusion index, polymerization pressure and temperature on the kinetics were studied. The kinetics parameters such as reaction order (n), the apparent activation energy (Ea) and the chain propagation rate constant (Kp) were determined and the concentration of active site (C*) was obtained by kinetic extrapolation method. The result indicates that the supported binuclear metallocene/MAO catalyst system exhibit a higher catalytic activity than that of single center system, attributed to its higher C* concentration and higher Kp. The slurry phase polymerization reaction rates shows 1.11 order dependency on monomer concentration, and Ea = 72.47 kJ/mol, C* = 0.33 mol/mol and Kp=1.06×106 L•(mol•h)-1 are found.
HTML  查看全文  查看/发表评论  下载PDF阅读器