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.

An interpolymer product comprising: a first ethylene interpolymer comprising ethylene and an α-olefin having a weight-average molecular weight (M.sub.w) of greater than 250,000 and a density of less than 0.930 g/cm.sup.3, and a second ethylene interpolymer comprising ethylene and an α-olefin wherein the second ethylene interpolymer comprises a M.sub.w of less than 70,000 and a density of greater than 0.930 g/cm.sup.3; and wherein the interpolymer product comprises an environmental stress crack resistance (ESCR), measured according to ASTM D1693, Condition B, 10% IGEPAL CO-630, of greater than 90 hours. The interpolymer product may be manufactured in a continuous solution polymerization process utilizing at least two reactors employing at least one single site catalyst formulation and at least one heterogeneous catalyst formulation.

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 composition comprising an ethylene/alpha-olefin interpolymer that comprises the following properties: a) a total unsaturation/1000C≥0.30; b) a molecular weight distribution (MWD)≤3.0; c) a TGIC broadness parameter B.sub.1/4≤8.0. A solution N polymerization process to prepare an ethylene/alpha-olefin/interpolymer, said process comprising polymerizing, in one reactor, at a reactor temperature ≥150° C., a reaction mixture comprising ethylene, an alpha-olefin, a solvent, and a metal complex as described herein. A method to determine the TGIC broadness parameter B.sub.1/x of a polymer composition comprising one or more olefin-based polymers.

A process to prepare an alpha composition comprising a first ethylene/alpha-olefin/interpolymer fraction and a second ethylene/alpha-olefin/interpolymer fraction; said process comprising polymerizing, in one reactor, a reaction mixture, comprising ethylene and an alpha-olefin, a biphenyl phenol metal complex selected from Structure 1, as described herein, and a biphenyl phenol metal complex selected from Structure 2, as described herein; and alpha compositions prepared therefrom.

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.

Disclosed is a catalyst for olefin polymerization, comprising a main catalyst and a cocatalyst; the main catalyst is a bisphenol metal complex represented by formula I, and the cocatalyst comprises an organoaluminum compound; in formula I, R.sub.1, R.sub.1′, R.sub.2, R.sub.2′ are the same or different, and are each independently selected from hydrogen and a substituted or unsubstituted C.sub.1-C.sub.20 hydrocarbyl; R.sub.3-R.sub.7, R.sub.3′-R.sub.7′ are the same or different, and are each independently selected from hydrogen and a substituted or unsubstituted C.sub.1-C.sub.20 hydrocarbyl; R.sub.8 and R.sub.9 are the same or different, and are each independently selected from hydrogen or a substituted or unsubstituted C.sub.1-C.sub.20 hydrocarbyl; M and M′ are the same or different, and are selected from Group IV metals; and X is halogen;

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