The present invention relates to a polypropylene-based composite material having improved physical properties including impact strength at low temperature and at room temperature, flexural strength, flexural modulus, etc., and a method for preparing the same.

The present disclosure relates to a polyethylene having high pressure resistance and a crosslinked polyethylene pipe including the same. The polyethylene according to the present disclosure has high melt index and density and exhibits a sufficient degree of crosslinking, thereby exhibiting excellent strength and pressure resistance characteristics.

The present invention relates to an ethylene/alpha-olefin copolymer having excellent processability. The ethylene/alpha-olefin copolymer according to the present invention has low complex viscosity at high shear rate and has excellent processability, and thus it could be applied to the processing of a large diameter pipe, a complex pipe or the like.

The present invention relates to a novel ligand compound, a transition metal compound and a catalyst composition including the transition metal compound. The novel ligand compound and the transition metal compound of the present invention may be usefully used as the catalyst of a polymerization reaction for preparing an olefin polymer having a low density relative to a CGC catalyst. In addition, a product having a low melt index (MI) and a high molecular weight may be manufactured using the olefin polymer polymerized using the catalyst composition including the transition metal compound.

Provided is an ethylene/1-hexene copolymer which has excellent long-term physical properties and processability, and thus may be usefully applied to manufacturing high-pressure resistant heating pipes, PE-RT pipes, large-diameter pipes, or the like.

Organometallic complexes are described which are useful as pre-polymerization catalysts which may form part of olefin polymerization catalyst systems. The catalyst systems find use in the polymerization of ethylene, optionally with one or more C.sub.3-12 alpha-olefin comonomers. The organometallic complexes are broadly represented by formula I:

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wherein L is a bridging group containing a contiguous chain of atoms connecting P with Cy, wherein the contiguous chain contains 2 or 3 atoms and wherein Cy is a cyclopentadienyl-type ligand. The olefin polymerization catalyst system is effective at polymerizing ethylene with alpha-olefins in a solution phase polymerization process at high temperatures and produces ethylene copolymers with high molecular weight and high degrees of alpha-olefin incorporation. Pre-metallation compounds, metallation processes and synthetic methods to make the organometallic complexes as well as polymerization processes are also described.

Provided is an olefin-based polymer with excellent processability. The olefin-based polymer according to the present invention has a high molecular weight and a broad molecular weight distribution to show excellent processability and improved mechanical properties, thereby being usefully applied according to the intended use.

A preparation method for a metallocene compound is provided. The method includes: stirring at least one compound I among compounds expressed by the following chemical formula (I) and a hydrogenation reaction catalyst of 0.10 to 0.55 parts by weight based on 100 parts by weight of the compound I under a hydrogen atmosphere; and obtaining a metallocene compound containing at least one first compound among the compounds expressed by the following chemical formula (1). Chemical formula (I) and (1) are provided in the specification.

The present invention relates to an olefin-based polymer exhibiting a single peak when analyzed by gel permeation chromatography (GPC), and having three elution temperatures Te1, Te2 and Te3 when measuring temperature rising elution fractionation (TREF) at a temperature ranging from 20 C. to 120 C. Accordingly, the olefin-based polymer having excellent mechanical strength, and in particular, significantly improved impact strength is provided.

The present invention relates to an ethylene/alpha-olefin copolymer having excellent processability. The ethylene/alpha-olefin copolymer according to the present invention has low complex viscosity at high shear rate and has excellent processability, and thus it could be applied to the processing of a large diameter pipe, a complex pipe or the like.