Provided is a hybrid catalyst composition including a first transition metal compound represented by Formula 1 and a second transition metal compound represented by Formula 2, the compounds being different from each other in the Formulae. The hybrid catalyst composition including the first and second transition metal compounds may exhibit high catalytic activity and may prepare a polyolefin having processability and mechanical properties.

The present invention relates to a polyolefin which exhibits a narrow molecular weight distribution, high strength, and a high stretching ratio, and a preparation method therefor. According to the present invention, it is possible to provide polyethylene with high catalyst activity, high molecular weight, and controlled molecular weight distribution by using, in polymerization of an olefin monomer, a hybrid supported metallocene catalyst in which a borate compound is used as a second cocatalyst. In addition, if the polyolefin is processed, it is possible to produce a fiber with excellent mechanical properties and an excellent stretching ratio.

This invention relates homogeneous (solution) polymerization of propylene at higher temperatures (80 C. or more) using bisindenyl metallocene catalyst compounds having long (at least 4 carbon atoms) linear alkyl groups substituted at the 2-position and substituted or unsubstituted aryl groups at the 4-position.

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 -olefins, cyclic olefins and linear, branched and cyclic dienes. According to the present invention, the high-density ethylene-based polymer 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.

The present invention relates to a catalyst composition for synthesizing an olefin copolymer, including a first metallocene catalyst, a second metallocene catalyst, and a third metallocene catalyst, each having a specific structure, and a method for preparing an olefin copolymer using the catalyst composition for synthesizing an olefin copolymer.

Disclosed is a propylene-diene copolymer resin having excellent melt tension, with improved melt strength, high molecular weight and broad molecular weight distribution by using a specific metallocene catalyst system. The present invention provides a propylene-diene copolymer resin produced by polymerizing propylene and a diene compound of C4-C20 by using a metallocene catalyst system, wherein the propylene-diene copolymer resin has the melt index (2.16 kg load at 230? C.) of 0.1-100 g/10 min and the melt tension (advanced rheometric expansion system (ARES)) of 5-100 g.

The present invention relates to a metallocene supported catalyst including a novel single metallocene compound having excellent polymerization activity, and a process for producing a polypropylene having excellent processability and broad molecular eight distribution using the same.

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.

The metallocene compound represented by the following general formula (1):

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(the numerals and signs in the general formula (1) are as described in the description).

Silica-coated alumina activator-supports, and catalyst compositions containing these activator-supports, are disclosed. Methods also are provided for preparing silica-coated alumina activator-supports, for preparing catalyst compositions, and for using the catalyst compositions to polymerize olefins.