The present invention relates to an olefin-based polymer, which has (1) a density (d) ranging from 0.85 to 0.90 g/cc, (2) a melt index (MI, 190 C., 2.16 kg load conditions) ranging from 0.1 g/10 min to 15 g/10 min, (3) a molecular weight distribution (MWD) in a range of 1.0 to 3.0, and (4) a number average molecular weight (Mn) and a Z+1 average molecular weight (Mz+1) satisfying the Equation 1, {Mn/(Mz+1)}100>15. The olefin-based polymer according to the present invention is a low-density olefin-based polymer and exhibits excellent tensile strength due to having improved molecular weight as compared to the flow index.

The present invention relates to a polypropylene-based resin composition which exhibits mechanical properties such as excellent strength and more improved impact strength, and a molded article comprising the same. The polypropylene-based resin composition comprises: a polypropylene-based resin; and an olefin-based copolymer, and shows two or more elution temperatures at a predetermined temperature range when analyzing the olefin-based copolymer by temperature rising elution fractionation (TREF).

Low molecular weight, highly branched polyolefins are provided. Also provided are catalyst-mediated methods of making the low molecular weight, highly branched polyolefins and a catalyst system for carrying out the methods. The catalyst system is a homogeneous catalytic system that includes a single-site organozirconium complex and hydrocarbon-soluble perfluoroarylborate co-catalyst that is highly active for the oligomerization of olefin monomers in non-polar media.

The present invention relates to an olefin-based polymer, which has (1) a density (d) ranging from 0.850 g/cc 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, (3) a melt temperature (Tm) of 10 C. to 100 C., and (4) a hardness (H, Shore A), the density (d) and the melt temperature (Tm) satisfying Equation 1, and Equation 2 or 3. The olefin-based polymer according to the present invention has low hardness and improved foaming properties, and exhibits improved impact strength at compounding.

Catalyst systems with single site transition metal complexes (such as pyridyldiamido transition metal complexes), an activator, and a metal hydrocarbenyl chain transfer agent (preferably an aluminum vinyl-transfer agent) are disclosed for use in alkene polymerization.

Catalyst systems including more than one metallocene catalysts and processes for using the same are provided to produce polyolefin polymers such as polyethylene polymers.

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.

Disclosed are catalyst systems comprising the reaction product of at least the following A) a procatalyst; and B) at least one cocatalyst structure selected from the following i) through iii), i) at least one cocatalyst comprising an anion having Structure 1 as shown below (Structure 1) as described herein; or ii) at least one cocatalyst comprising an anion having Structure 2 as shown below (Structure 2) as described herein; or iii) a combination of i and ii.

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The present invention provides a spherical supported transition metal catalyst. The catalyst carrier is a spherical titanium/zirconium hydrophosphate compound, the primary catalyst is a transition metal compound, the co-catalyst is methylaluminoxane; the spherical titanium/zirconium hydrophosphate compound comprises one or several combinations of titanium hydrophosphate, modified titanium hydrophosphate and zirconium hydrophosphate. The present invention also provides a preparation method of said spherical supported transition metal catalyst and a use thereof in olefin polymerization, as well as the spherical titanium/zirconium hydrophosphate compound and its preparation method. The spherical, supported transition metal catalyst in the present invention has a high catalytic activity, and the polymer particles obtained have good morphology.

Polyethylene compositions including at least 65 wt % ethylene derived units, based upon the total weight of the polyethylene composition, are provided.