Journal of Polymer Science Part A: Polymer Chemistry, Vol.40, No.16, 2759-2771, 2002
Homopolymerizations and random copolymerizations of olefins with amino-substituted cyclopentadienylchromium complexes
1-(2 N,N-Dimethylaminoethyl)-2,3,4,5-tetramethylcyclopentadienyl-chromium dichloride (1), (2-N,N-dimethylaminoethyl)cyclopentadienylchromium dichloride (6), and (2-N,N-dimethylaminoethyl)indenylchromium dichloride (7) in the presence of modified methylaluminoxane exhibit high catalytic activities for the polymerization of ethylene with random copolymerizations of ethylene with propylene, ethylene with 1-hexene, and propylene with 1-hexene. These initiators conduct polymerizations to give high molecular weight polymers with low polydispersities. However, the stereo-regularities are very poor in these reactions.
Keywords:organochromium complexes;polyethylene (PE);polyethylene-co-propylene);polyethylene-co-1-hexene);polypropylene-co-1-hexene);initiator;polyolefins;copolymerization