This invention relates to a polymerization catalyst system comprising group 8 or 9 containing non-coordinating anion activator, a polymerization catalyst compound, optional support, and optional scavenger. Preferably, the activator comprises a compound represented by the formula: H.sub.s(L).sub.mM where M is a group 8 or 9 metal, s is 0 or 1, m 1, 2, 3, or 4, each L ligand is independently C≡O, NR.sub.3, PR.sub.3, where each R, independently is halogen, haloalkyl, or haloaryl) or optionally two or more L ligands may together form a multiply-valent ligand complex. Further, this invention relates to anon-coordinating anion activator represented by the formula: [Z.sub.d].sup.+[H.sub.sL.sub.mM].sup.d−, where M, s, m, L, are as defined above, d is 1, 2, or 3 and Z is (L′-H) or a reducible Lewis acid; L′ is a neutral Lewis base; H is hydrogen, and (L′-H) is a Bronsted acid. This invention also relates to a process for making a polymeric product comprising contacting a C2-C40 alpha-olefin feed with the polymerization catalyst system to obtain a polymerization reaction mixture; and obtaining a polymer product from the polymerization reaction mixture.

Processes and apparatus for preparing bimodal polymers are provided. In some embodiments, processes include introducing a monomer, a first diluent, a catalyst, hydrogen, at a first hydrogen concentration, and optional comonomer, to a first loop reactor to produce, under polymerization conditions, a first slurry of polymer solids. Processes may also include continuously discharging the first slurry of polymer solids from the loop reactor as a first polymerization effluent to a first flash tank; separating the first polymerization effluent in the first flash tank to provide a first concentrated polymer slurry with significantly lower hydrogen concentration; and transferring the first concentrated polymer slurry from the flash tank to a re-slurry mixer. Processes may further include introducing a re-slurry mixer diluent to the first concentrated polymer slurry to form a second concentrated polymer slurry in the re-slurry mixer that can be pumped to a second slurry loop reactor.

The present invention relates to a high-density ethylene-based polymer comprising an ethylene homopolymer or a copolymer of ethylene and at least one comonomer selected from the group consisting of an α-olefin, a cyclic olefin, and a straight, branched and cyclic diene. According to the present invention, the high-density polyethylene resin has a wide molecular weight distribution and excellent comonomer distribution characteristics, has excellent melt flowability due to a long chain branched structure, and has excellent mechanical characteristics since the comonomer distribution is concentrated in a high-molecular-weight body. The high-density ethylene polymer of the present invention has excellent molding processability during processing such as extrusion, compression, injection and rotational molding by having excellent mechanical characteristics and melt flowability.

Unsaturated and hydrogenated polyalpha-olefin products can be made with a high selectivity toward vinylidenes and tri-substituted vinylenes combined, a high selectivity toward vinylidenes, and a low selectivity toward 1,2-di-substituted vinylenes by using a catalyst system comprising a metallocene compound having the following structure in the polymerization reaction: ##STR00001##

In one aspect, oligomeric and polymeric species are described herein exhibiting new architectures and associated properties. In some embodiments, such species are synthesized by oligomerization or polymerization of diene monomer via cycloaddition in the presence of a transition metal complex. Oligomers described herein, for example, comprise cyclobutane units in the oligomer backbone. Similarly, a polymers described herein comprise cyclobutane units in the polymer backbone.

Processes and apparatus for preparing bimodal polymers are provided. In some embodiments, processes include introducing a monomer, a first diluent, a catalyst, hydrogen, at a first hydrogen concentration, and optional comonomer, to a first loop reactor to produce, under polymerization conditions, a first slurry of polymer solids. Processes may also include continuously discharging the first slurry of polymer solids from the loop reactor as a first polymerization effluent to a first flash tank; separating the first polymerization effluent in the first flash tank to provide a first concentrated polymer slurry with significantly lower hydrogen concentration; and transferring the first concentrated polymer slurry from the flash tank to a re-slurry mixer. Processes may further include introducing a re-slurry mixer diluent to the first concentrated polymer slurry to form a second concentrated polymer slurry in the re-slurry mixer that can be pumped to a second slurry loop reactor.

A process to produce a branched ethylene--olefin diene elastomer comprising combining a catalyst precursor and an activator with a feed comprising ethylene, C3 to C12 -olefins, and a dual-polymerizable diene to obtain a branched ethylene--olefin diene elastomer; where the catalyst precursor is selected from pyridyldiamide and quinolinyldiamido transition metal complexes. The branched ethylene--olefin diene elastomer may comprise within a range from 40 to 80 wt % of ethylene-derived units by weight of the branched ethylene--olefin diene elastomer, and 0.1 to 2 wt % of singly-polymerizable diene derived units, 0.1 to 2 wt % of singly-polymerizable diene derived units, and the remainder comprising C3 to C12 -olefin derived units, wherein the branched ethylene--olefin diene elastomer has a weight average molecular weight (M.sub.w) within a range from 100 kg/mole to 300 kg/mole, an average branching index (g.sub.avg) of 0.9 or more, and a branching index at very high M.sub.w (g.sub.1000) of less than 0.9.

Disclosed herein are a chromium compound represented by Formula 1a or 1c and a catalyst system including the same, exhibiting superior catalytic activity in an olefin trimerization reaction:
[{CH.sub.3(CH.sub.2).sub.3CH(CH.sub.2CH.sub.3)CO.sub.2}.sub.2Cr(OH)][Formula 1a]
[{CH.sub.3(CH.sub.2).sub.3CH(CH.sub.2CH.sub.3)CO.sub.2}.sub.2Cr(OH)].sub.4.2H.sub.2O.[Formula 1c]

A procatalyst for the polymerization of ethylene and optionally one or more alpha-olefins having the structure shown in formula (I) below. Formula (I) is provided. Also provided is a polymerization process using the inventive procatalyst. ##STR00001##

The present invention relates to a self assembled catalyst. More particularly, the present invention relates to a self-assembled catalyst of formula (I) comprising supramolecular phosphine and carboxylate ligands, process for preparation thereof and use of said catalyst of formula (I) in olefin polymerization.