The present invention relates to polyethylene resin having excellent impact strength, and more specifically, to polyethylene resin exhibiting excellent impact strength and flexural strength, when prepared into a molded product.

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).

An ethylene/alpha-olefin copolymer having excellent physical properties showing reduced immersion time of a crosslinking agent and a high degree of crosslinking, and a composition for an encapsulant film, comprising the same, is described herein.

The polyethylene according to the present disclosure has a short relaxation time and a uniform particle size, thereby preparing a chlorinated polyethylene excellent in chlorination productivity and glass transition temperature by reacting with chlorine. And, a PVC composition with improved impact strength may also be prepared by including the same.

A polyolefin composition having high transparency, made from or containing: A) a propylene polymer, alternatively a heterophasic polyolefin composition made from or containing the propylene polymer and an ethylene copolymer; B) from 0.01% to 2% by weight of a butene-1 polymer; and C) a clarifying agent; wherein the amounts are referred to the total weight of A)+B)+C).

A method of preparing a supported metallocene catalyst capable of more effectively preparing a polyolefin which may be preferably used for blow molding, etc., because its molecular weight distribution is such that polymer elasticity is increased to improve swell, is provided.

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:

##STR00001##

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 are a transition metal compound for an olefin polymerization catalyst, an olefin polymerization catalyst containing the transition metal compound, and a polyolefin prepared using the olefin polymerization catalyst for polymerization thereof, wherein the transition metal compound is represented by Chemical Formula 1.

The present invention relates to a novel ligand compound, a transition metal compound and a catalyst composition comprising the same. The novel ligand compound and the transition metal compound of the present invention may be useful as a catalyst of polymerization reaction for preparing an olefin-based polymer having a low density.

The present disclosure provides a novel transition metal compound having excellent structural stability together with polymerization reactivity, and thereby is useful as a catalyst in preparing an olefin-based polymer, particularly, a high molecular weight and low density olefin-based polymer, and a catalyst composition including the same.