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.

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.

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 disclosure relates to a method for preparing a polyolefin using a supported hybrid metallocene catalyst. According to the present disclosure, a polyolefin having a narrow molecular weight distribution can be prepared very effectively by introducing a cocatalyst in an optimum content in the presence of a supported hybrid metallocene catalyst containing two or more metallocene compounds having a specific chemical structure. The polyolefin prepared according to the present disclosure exhibits excellent uniformity in chlorine distribution in polyolefin during chlorination, thereby significantly improving elongation of the chlorinated polyolefin, compatibility with PVC and impact reinforcing performance. Thus, it exhibits excellent chemical resistance, weather resistance, flame retardancy, processability and impact strength reinforcing effect, and can be suitably applied as an impact reinforcing agent for PVC pipes and window profiles.

The present invention relates to polyolefin. More specifically, the present invention relates to polyolefin having excellent dart drop impact strength, and exhibiting improved transparency, and such polyolefin has a density of 0.915 g/cm3 to 0.930 g/cm3 measured according to ASTM D1505; and satisfies the following requirements (provided that S1+S2+S3=1), when measuring the relative content of peak area according to melting temperature (Tm) using SSA (Successive Self-nucleation and Annealing) analysis: the content(S1) of peak area at Tm less than 100° C. is 0.33 to 0.35; the content(S2) of peak area at Tm of 100° C. or more and 120° C. or less is 0.52 to 0.56; and the content(S3) of peak area at Tm greater than 120° C. is 0.10 to 0.14.

The present invention relates to an olefin-based polymer, which has (1) a density (d) ranging from 0.850 to 0.865 g/cc, (2) a melt index (MI, 190° C., 2.16 kg load conditions) ranging from 0.1 g/10 min to 3.0 g/10 min, and (3) a soluble fraction (SF) of 10 wt % or more at −20° C. in cross-fractionation chromatography (CFC), in which a weight average molecular weight (Mw) of the soluble fraction is in a range of 50,000 g/mol to 500,000 g/mol. The olefin-based polymer according to the present invention exhibits improved anti-blocking properties as a low-density olefin-based polymer.

Provided is an ethylene/1-butene copolymer having excellent processability and stress cracking resistance. The ethylene/1-butene copolymer according to the present invention may be applied to a high-pressure resistant heating pipe, a PE-RT pipe, a large diameter pipe, etc.

Catalyst systems and methods for making and using the same. A method of methylating a catalyst composition while substantially normalizing the entiomeric distribution is provided. The method includes slurrying the organometallic compound in dimethoxyethane (DME), and adding a solution of RMgBr in DME, wherein R is a methyl group or a benzyl group, and wherein the RMgBr is greater than about 2.3 equivalents relative to the organometallic compound. After the addition of the RMgBr, the slurry is mixed for at least about four hours. An alkylated organometallic is isolated, wherein the methylated species has a meso/rac ratio that is between about 0.9 and about 1.2.

Ethylene-based polymers are characterized by a density from 0.92 to 0.955 g/cm.sup.3, a HLMI of less than 35 g/10 min, and a ratio of a number of short chain branches (SCBs) per 1000 total carbon atoms at Mz to a number of SCBs per 1000 total carbon atoms at Mn in a range from 11.5 to 22. These polymers can have a higher molecular weight (HMW) component and a lower molecular weight (LMW) component, in which a ratio of a number of SCBs per 1000 total carbon atoms at Mn of the HMW component to a number of SCBs per 1000 total carbon atoms at Mn of the LMW component is in a range from 10.5 to 22. These ethylene polymers can be produced using a dual catalyst system containing an unbridged metallocene compound with an indenyl group having at least one halogen-substituted hydrocarbyl substituent with at least two halogen atoms, and a single atom bridged metallocene compound with a fluorenyl group and a cyclopentadienyl group.