Embodiments are directed towards the use of a supported biphenylphenol polymerization catalyst made from a biphenylphenol polymerization precatalyst of Formula I via a gas-phase or slurry-phase polymerization process under gas-phase or slurry-phase polymerization conditions to make a polymer.

Embodiments are directed towards the use of a supported biphenylphenol polymerization catalyst made from a biphenylphenol polymerization precatalyst of Formula I via a gas-phase or slurry-phase polymerization process under gas-phase or slurry-phase polymerization conditions to make a polymer.

The present disclosure relates to a polyethylene composition capable of producing a molded product having excellent environmental stress crack resistance, and improving total volatile organic compound (TVOC) properties that can be generated by a low molecular weight polymer, and a method for preparing the same.

The present disclosure relates to an ethylene/1-hexene copolymer having excellent flexibility and processability and useful for manufacturing high-pressure heating pipes, PE-RT pipes or large-diameter pipes.

Provided are a metallocene supported catalyst capable of greatly reducing generation of fine powder during preparation of olefin polymers while exhibiting excellent catalyst activity, and a method of preparing olefin polymers using the same.

Provided are a metallocene supported catalyst capable of greatly reducing generation of fine powder during preparation of olefin polymers while exhibiting excellent catalyst activity, and a method of preparing olefin polymers using the same.

The present invention relates to heterophasic polypropylene compositions comprising a propylene homo- or copolymer forming a crystalline fraction as a matrix and an amorphous propylene ethylene elastomer as a soluble fraction dispersed in said matrix. The heterophasic polypropylene compositions further comprise an elastomeric ethylene/alpha-olefin random copolymer. The heterophasic polypropylene compositions have a well-balanced relation between stiffness and impact strength, low volatile and semi-volatile emissions and good processability.

A metallocene compound having a structure shown by formula (I). A functional group connected to a bridging atom of the metallocene compound is an amine-substituted group and/or a metallocene-substituted group and/or a substituted metallocene group. A metallocene catalyst containing the metallocene compound has high catalytic activity, and can synthesize metallocene polypropylene having high isotacticity.

R.sup.IR.sup.IIZ(Cp.sup.III).sub.n(E).sub.2-nML.sup.IVL.sup.V   (I)

Provided is a method of predicting fouling during a process of preparing polyolefin. According to the present invention, occurrence of fouling may be predicted by calculating R value according to the following Equation 1 in real-time with high reliability during a copolymerization process of preparing polyolefin:
R (ratio of unreacted alpha-olefin comonomer to produced polyolefin polymer) =amount of unreacted alpha-olefin comonomer (unit: kg/hr) / amount of produced polyolefin polymer (unit: kg/hr)   [Equation 1] Therefore, productivity of the polyolefin preparation process may be further increased.

This invention relates to polyolefin. More specifically, this invention relates to polyolefin that has small copolymer content, but exhibits excellent mechanical properties.