Ethylene-based polymers having a density of 0.952 to 0.968 g/cm.sup.3, a ratio of HLMI/MI from 185 to 550, an IB parameter from 1.46 to 1.80, a tan δ at 0.1 sec.sup.−1 from 1.05 to 1.75 degrees, and a slope of a plot of viscosity versus shear rate at 100 sec.sup.−1 from 0.18 to 0.28 are described, with low melt flow versions having a HLMI from 10 to 30 g/10 min and a Mw from 250,000 to 450,000 g/mol, and high melt flow versions having a HLMI from 30 to 55 g/10 min and a Mw from 200,000 to 300,000 g/mol. These polymers have the processability of chromium-based resins, but with improved stress crack resistance and topload strength for bottles and other blow molded products.

A system and method of producing polyethylene, including: polymerizing ethylene in presence of a catalyst system in a reactor to form polyethylene, wherein the catalyst system includes a first catalyst and a second catalyst; and adjusting reactor conditions and an amount of the second catalyst fed to the reactor to control melt index (MI), density, and melt flow ratio (MFR) of the polyethylene.

Embodiments of polyethylene compositions and articles comprising polyethylene compositions are disclosed. The polyethylene compositions may include a first polyethylene fraction area defined by an area in the elution profile in a temperature range of 70° C. to 97° C. via improved comonomer composition distribution (iCCD) analysis method; a first peak in the temperature range of 70° C. to 97° C. in the elution profile; a second polyethylene fraction area defined by an area in the elution profile in a temperature range of 97° C. to 110° C.; and a second peak in the temperature range of 97° C. to 110° C. The polyethylene composition may have a density of 0.935 g/cm.sup.3 to 0.955 g/cm.sup.3 and a melt index (I.sub.2) of 1.0 g/10 minutes to 10.0 g/10 minutes. A ratio of the first polyethylene fraction area to the second polyethylene fraction area may be less than 2.0.

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Embodiments of the present application are directed to procatalysts, and catalyst systems including procatalysts, including a metal-ligand complex having the structure of formula (I):

The present invention relates to filtration media made from melt-blown fibers having improved barrier properties. The melt-blown fibers in the filtration media of the invention are made of a visbroken metallocene-catalyzed propylene homopolymer composition with specified melting temperature Tm and molecular weight distribution (MWD).

A heterophasic polypropylene copolymer having an MFR2 of 0.05 to 20 g/10 min (ISO 1133 at 230° C. with a loading of 2.16 kg) and a melting point (Tm) of 156 to 164° C. (measured by DSC according to ISO 11357) wherein the heterophasic polypropylene copolymer comprises at least the following components: (A) 55.0 to 95.0 wt % of a crystalline fraction (CF) having a comonomer content of 0 to 3.0 wt %; and (B) 5.0 to 45.0 wt % of a soluble fraction (SF) having a comonomer content of 12 to 45 wt %; wherein the intrinsic viscosity (IV) (in decalin at 135° C.) of the soluble fraction (SF) is 2.5 to 11 dl/g, and wherein the amount of crystalline fraction (CF) and the amount of soluble fraction (SF) are determined in 1,2,4-trichlorobenzene at 40° C.

Non-coordinating borate activators deposited upon a support material may be effective for promoting olefin polymerization in the presence of a suitable transition metal complex, particularly for gas phase and slurry polymerization reactions. The non-coordinating borate activators may be deposited upon the support material using substantially aliphatic hydrocarbon solvents, preferably in the absence of aromatic solvents, such as toluene.

The present invention relates to a polyolefin film and to a process for preparing the same. The polyolefin film, specifically, the linear low-density polyethylene film according to an embodiment of the present invention is readily formed and has excellent mechanical strength and excellent heat seal characteristics.

A catalyst system including the product of the combination of an unbridged Group 4 metallocene compound and a 2,6-bis(imino)pyridyl iron complex is provided. A process for the polymerization of monomers (such as olefin monomers) and a polymer produced therefrom are also provided.

The present invention relates to melt-blown webs having no shots and improved barrier properties, whereby the melt-blown webs are made of a visbroken metallocene-catalyzed propylene homopolymer composition with specified melting temperature T.sub.m, content of 2,1 erythro regiodefects and molecular weight distribution (MWD).