Provided are a novel metallocene compound, a metallocene-supported catalyst, and a method of preparing a polyolefin using the same. The metallocene-supported catalyst according to the present disclosure exhibits a high polymerization activity even when the metallocene compound is supported on a support, thereby showing an excellent activity and preparing a polyolefin having a high molecular weight.

A solid catalyst component for the (co)polymerization of olefins CH.sub.2CHR, in which R is a hydrocarbyl radical with 1-12 carbon atoms, optionally in mixture with ethylene, comprising Ti, Mg, Cu, Cl, and an electron donor compound characterized by the fact that the Cu/Ti weight ratio is lower than 0.5.

The present invention relates to an (ultra) high molecular weight polyethylene-based block copolymer having (ultra) high molecular weight polyethylene as a first-stage polymer in a linear structure through multi-stage polymerization and having a viscosity average molecular weight of 400,000 to 5,000,000 g/mol under the conditions that hydrogen (H.sub.2) as a molecular weight regulator is added in a trace amount or not added, a producing method therefor, and a secondary battery separator produced using the same as a raw material. The present invention provides improved kneading property, film surface and other properties compared to a heterogeneous composite secondary battery separator made of polyethylene and polypropylene processed by simple blending.

The present invention relates to an (ultra) high molecular weight polyethylene-based block copolymer having (ultra) high molecular weight polyethylene as a first-stage polymer in a linear structure through multi-stage polymerization and having a viscosity average molecular weight of 400,000 to 5,000,000 g/mol under the conditions that hydrogen (H.sub.2) as a molecular weight regulator is added in a trace amount or not added, a producing method therefor, and a secondary battery separator produced using the same as a raw material. The present invention provides improved kneading property, film surface and other properties compared to a heterogeneous composite secondary battery separator made of polyethylene and polypropylene processed by simple blending.

Embodiments of this disclosure are directed to catalyst systems comprising a metal-ligand complex according to formula (I):

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Embodiments of this disclosure are directed to catalyst systems comprising a metal-ligand complex according to formula (I):

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