Heterogeneous catalyst mixtures for the polymerization of ethylene

Characteristics of linear/branched polyethylene reactor blends synthesized by metallocene/late transitional metal hybrid catalysts

“…Examples mainly include production of bimodal MWD by hybrid catalyst (both catalysts supported on the same support) [19][20][21][22][23]. Further, application of mixed homogenous and/or heterogeneous dual metallocene systems or the corresponding hybrid catalysts was seen to have more flexibility for control of chain microstructure [24][25][26][27]. Kim et al [25] utilized metallocenes with different hydrogen response to tune MWD from unimodal to bimodal distribution by changing hydrogen concentration.…”

“…Hong et al [26] used metallocenes with different capability of comonomer incorporation to provide bimodal MWD with inverse comonomer content. Alt et al synthesized similar microstructure using heterogeneous triple catalytic system, so that one of the catalysts provides a-olefin comonomer and the other catalysts incorporate it at different extends into the growing chains [27]. Such polymers are normally produced by cascade reactor technology using a single catalyst.…”

Uniform, Axial‐Orientation Alignment of One‐Dimensional Single‐Crystal Silicon Nanostructure Arrays

“…Moreover, the incorporation of comonomer and polymerization behavior also strongly depended on these structured nano‐confinement channels when ethylene copolymerization was conducted using an Et(Ind) 2 ZrCl 2 /MCM‐41‐supported catalyst 28. Schilling et al used MCM‐41 as a support for ternary metal catalysts to study ethylene polymerization 29. They found that MCM‐41‐based catalysts exhibited higher polymerization activities than ‘Davison silica’‐based homogeneous catalysts or heterogeneous catalysts.…”

Novel bis(benzoin) titanium catalyst for homo- and copolymerization of norbornene with ethylene: Synthesis, characterization and catalytic properties

“…The melting points of the polymers measured by DSC are in the 130.7-136.3 C region, indicating that the produced polymers possess linear structures with virtually no branching. The poor solubility of the high-molecular weight linear PEs in trichlorobenzene made it difficult to analyze by GPC, thus the molecular weight was calculated from the viscosity determined by an Ubbelohde viscosimeter in decalin at 135 C. The listed data indicate that the molecular weights of the obtained PEs are very high up to 10 6 g mol À1 , and decrease with the increase of polymerization temperature uniformly due to an increasing chain termination reaction rate [47]. The molecular weight of the PE is unchanged with polymerization time.…”