Quantitative structure–property relationship (QSPR) modeling is performed to investigate the role of cycloalkyl-fused rings on catalytic performance 46 aryliminopyridyl nickel precatalysts. The activities for complexes in ethylene polymerization are well-predicted by obtained 2D-QSPR model, exploring main contribution from charge distribution negatively charged atoms. Comparatively, 3D-QSPR mod...

The coordination polymerization of ethylene in water as a reaction medium was studied. Rubbery amorphous branched polyethylene was obtained when a known cationic diimine-substituted methyl complex was employed as a catalyst precursor. High rates of up to 900 TOh(-1) (turnover frequency) were observed. In contrast to solution polymerization in an organic solvent, the rate of suspension polymeriz...

Since the advent of Ziegler-Natta polymerization of ethylene, attempts have been made to extend coordination polymerization to commercially important monomers with polar functionality. In this study we examined the copolymerization of perdeuterated vinyl chloride (VC) and perdeuterated vinyl acetate (VA) with ethylene using a tridentate Fe(II) dichloride pyridine diimine metal catalyst. The res...

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The copolymerizations of a gaseous monomer (ethylene) and a liquid monomer (vinyl acetate) via emulsion and miniemulsion polymerizations are reported. Reactions in which the vinyl acetate was introduced in both batch and semibatch modes are carried out. (Ethylene introduction is always in a semibatch model since the polymerization is carried out under a constant pressure of ethylene in the reac...

Strict morphological control over growing polymer particles is an indispensable requirement in many catalytic olefin polymerization processes. In catalysts with mechanically stronger supports, e. g., polymerization-grade silicas, the emergence of extensive cracks via sectioning fragmentation mechanism requires severe stress build-up polymerizing catalyst particle. Here, we report on three facto...

heterogeneous ziegler-natta and homogeneous metallocene catalysts exhibit greatly different active sitenature in olefin polymerization. in our previous study, it was reported that mgcl2-supported titanocenecatalysts can generate both ziegler-natta-type and metallocene-type active sites according to the type of activators.the dual active site nature of the supported titanocene catalysts was furt...

The elementary processes involved in the polymerization of ethylene by soluble Ziegler catalysts of the type Cp2TiMeCl/AlMeCl2 have been studied by C N M R spectroscopy. Using Cenriched ethylene, detailed information was obtained directly on the system in the course of the polymerization. No spectroscopic evidence was found for precoordination of the monomer. The development of the oligomer dis...

Emulsion polymerization is one of the most important and versatile polymerization processes. About 10 million tonnes of polymer latices are produced annually for a variety of applications, such as coatings and paints. A key step in most applications is film formation upon evaporation of the dispersing medium, rendering aqueous dispersions particularly environmentally benign. Polymer dispersions...