文献类型：期刊文献

英文题名：Novel SiO2-Supported Silyl-Chromate(Cr)/Imido-Vanadium(V) Bimetallic Catalysts Producing Polyethylene and Ethylene/1-Hexene Copolymers with Bimodal Molecular-Weight Distribution

作者：Zhao, Ning[1];Cheng, Ruihua[1];He, Xuelian[1];Liu, Zhen[1];Liu, Boping[1];Zhang, Rui[2];Gao, Yuxin[2];Zou, Enguang[2];Wang, Sihan[2]

机构：[1]E China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]Petrochem Res Inst PetroChina, Daqing Petrochem Res Ctr, Daqing City 163714, Heilongjiang, Peoples R China

年份：2014

卷号：215

期号：15

起止页码：1434

外文期刊名：MACROMOLECULAR CHEMISTRY AND PHYSICS

收录：;EI(收录号：20143318051994);WOS:【SCI-EXPANDED(收录号:WOS:000340414900003)】；

基金：The authors gratefully acknowledge financial support from the National Natural Science Foundation of China (No. 21104019 and 21274040) and the National High Technology Research and Development Program 863 (2012AA040306). This work was also financially supported by the Fundamental Research Funds for the Central Universities, research program of Introducing Talents of Discipline of university (B08021) and PetroChina.

语种：英文

外文关键词：bimodal molecular-weight distribution (MWD); copolymerization; kinetics (polym); imido V compounds; novel Cr-imido V bimetallic catalyst

摘要：Novel SiO2-supported silyl-chromate(Cr)/imido-vanadium(V) (Cr-imidoV) bimetallic catalysts for ethylene and ethylene/-olefin polymerization are investigated. These catalysts are prepared using the residual surface hydroxyl groups in SiO2-supported imido-vanadium catalysts to further support bis(triphenylsilyl) chromate (BC) in order to get the merits from both the SiO2-supported imido vanadium catalyst and the SiO2-supported silyl chromate S-2 catalyst. By investigation of the polymerization behavior and the microstructures of their polymers, several vital factors such as the addition amount of imido vanadium active centers and the dosage of 1-hexene in the ethylene homopolymerization and ethylene/1-hexene copolymerization are systematically investigated. Compared with the traditional S-2 catalyst and our previously reported SiO2-supported silyl-chromate(Cr)/vanadium(V)-oxide (Cr-V) bimetallic catalyst, the novel Cr-imidoV bimetallic catalysts show even higher activity and better 1-hexene incorporation ability, together with higher molecular weight (MW) and bimodal molecular-weight distribution (MWD).