writer：15. Min Yang, Binyuan Liu, Luhai Wang, Hegang Ren, Wenyan Hu, Lifang Wen, Weidong Yan*
keywords：tandem catalyst, LLDPE
source：期刊
specific source：Catal Commun, 2009, 10, 1427-1431
Issue time：2009年

Tandem catalytic systems, consisting of one catalyst with two different activators, were successfully employed in preparing branched polyethylene from ethylene as sole monomer. The catalyst precursor (b-diketonate zirconium) was used in combination with diethylaluminium chloride (AlEt2Cl) and methylaluminoxane
(MAO) (or trialkylaluminum AlR3) as cocatalysts to form the oligomerization active species and copolymerization active species, respectively. The 13C NMR spectrum revealed that the resultant polymer was branched polyethylene. The molar ratio between the two cocatalysts had a remarkable effect on the catalytic activity and the properties of copolymer, such as melting temperature, crystallinity, molecular
weight and molecular weight distribution.