ETHYLENE POLYMERIZATION AND ETHYLENE/HEXENE COPOLYMERIZAION WITH VANDIUM CATALYSTS BEARING THIOPHENOL-PHOSPHINE LIGANDS
ETHYLENE POLYMERIZATION AND ETHYLENE/HEXENE COPOLYMERIZAION WITH VANDIUM CATALYSTS BEARING THIOPHENOL-PHOSPHINE LIGANDS作者机构:State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences
出 版 物:《Chinese Journal of Polymer Science》 (高分子科学(英文版))
年 卷 期:2013年第31卷第6期
页 面:885-893页
核心收录:
学科分类:081705[工学-工业催化] 0817[工学-化学工程与技术] 08[工学] 0805[工学-材料科学与工程(可授工学、理学学位)] 080502[工学-材料学] 0703[理学-化学]
基 金:supported by the National Natural Science Foundation of China (No. 21234006)
主 题:Ziegler-Natta polymerization Vanadium catalyst Polyethylene Copolymerization.
摘 要:Vanadium(III) complexes bearing thiophenol-phosphine ligands (2a-2b) (2-R-6-PPh2-C6H2S) VC12(THF)2 (2a: R = H; 2b: R = MeaSi) were prepared from VCla(THF)3 by treating with 1.0 equiv of the ligand in tetrahydrofuran in the presence of excess triethylamine. The two complexes were characterized by FTIR and mass spectra as well as elemental analyses. On activation with Et2AIC1, these complexes exhibited high catalytic activities (up to 22.1 kg PE/(***)) even at high temperature (70 ℃), and produced high molecular weight polymers with unimodal molecular weight distributions, indicating the polymerization took place in a single-site nature. This result may be attributed to benefits of introduction of second-row donor atoms for adjusting charge density of the vanadium centers. In addition, these complexes also exhibited high catalytic activities for ethylene/1-hexene copolymerization. Catalytic activity, comonomer incorporation and polymer molecular weight can be controlled in a wide range by the variation of catalyst structure and the reaction parameters such as A1/V molar ratio, comonomer feed concentration and polymerization reaction temperature.