A process for the preparation of polyolefins by polymerizing olefins at temperatures of from 20 to 200° C. and pressures of from 0.1 to 20 MPa in the presence of a polymerization catalyst and an antistatically acting composition in a polymerization reactor, wherein the antistatically acting composition is a mixture comprising an oil-soluble surfactant and water and the use of an antistatically acting composition comprising an oil-soluble surfactant and water as antistatic agent for the polymerization of olefins at temperatures of from 20 to 200° C. and pressures of from 0.1 to 20 MPa in the presence of a polymerization catalyst.

A system and method of producing polyethylene, including: polymerizing ethylene in presence of a catalyst system in a reactor to form polyethylene, wherein the catalyst system includes a first catalyst and a second catalyst; and adjusting reactor conditions and an amount of the second catalyst fed to the reactor to control melt index (MI), density, and melt flow ratio (MFR) of the polyethylene.

Catalyst systems and methods for making and using the same. A method of methylating a catalyst composition while substantially normalizing the entiomeric distribution is provided. The method includes slurrying the organometallic compound in dimethoxyethane (DME), and adding a solution of RMgBr in DME, wherein R is a methyl group or a benzyl group, and wherein the RMgBr is greater than about 2.3 equivalents relative to the organometallic compound. After the addition of the RMgBr, the slurry is mixed for at least about four hours. An alkylated organometallic is isolated, wherein the methylated species has a meso/rac ratio that is between about 0.9 and about 1.2.

The invention relates to power cable polymer composition which comprises a thermoplastic polyethylene having a chlorine content which is less than X, wherein X is 10 ppm, a power cable, for example, a high voltage direct current (HV DC), a power cable polymer insulation, use of a polymer composition for producing a layer of a power cable, and a process for producing a power cable.

Catalyst systems and methods for making and using the same. A method of polymerizing olefins to produce a polyolefin polymer with a multimodal composition distribution, includes contacting ethylene and a comonomer with a catalyst system. The catalyst system includes a first catalyst compound and a second catalyst compound that are co-supported to form a commonly supported catalyst system. The first catalyst compound includes a compound with the general formula (C.sub.5H.sub.aR.sup.1.sub.b)(C.sub.5H.sub.cR.sup.2.sub.d)HfX.sub.2. The second catalyst compound includes at least one of the following general formulas:

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In both catalyst systems, the R groups can be independently selected from any number of substituents, including, for example, H, a hydrocarbyl group, a substituted hydrocarbyl group, or a heteroatom group, among others.

The present invention relates to a transition metal compound that may exhibit high activity in olefin polymerization, and easily control the properties of synthesized olefin polymer such as a chemical structure, molecular weight distribution, a mechanical property, and the like, a catalyst composition comprising the same, and a method for olefin polymerization using the catalyst composition.

The present disclosure provides a gas-phase polymerization process for preparing polyethylene, wherein halogenated alcohols in combination with a Ti based catalyst component and aluminum alkyls as co-catalyst suppress ethane formation or increase polymerization activity.

Modified chromium-based catalyst compositions for olefin polymerization are disclosed. The modifiers prevent or reduce catalyst particle aggregation providing improved catalyst particle dispersion and consistent flow index response of the compositions in olefin polymerization.

The present invention relates to a pipe comprising an ethylene-based polymer, wherein the ethylene-based polymer: ⋅ comprises ≥0.10 mol % of units derived from 1-hexene, with regard to the total molar quantity of polymeric units of the ethylene-based polymer; ⋅ has an M.sub.w/M.sub.n as determined in accordance with ASTM D6474 (2012) of ≥2.5 and ≤4.0, preferably of ≥2.5 and ≤3.4; ⋅ has a density as determined in accordance with ASTM D792 (2008) of ≥925 and ≤945 kg/m.sup.3; and ⋅ in the molecular weight range of log(M.sub.w) between 4.0 and 5.5, has a comonomer branch content of between 2 and 15 comonomer-derived branches per 1000 carbon atoms in the polymer, as determined via .sup.13C NMR. Such pipe provides a desirably high long-term strength, as demonstrated by its high strain hardening modulus, as well as desirably high impact strength, as demonstrated by its high Charpy impact strength. Further, such pipe may be compliant with the PE-RT requirements of ISO 22391-1 (2009). For example, such pipe may be used for containing water at temperatures in the range of 40° C. to 80°.

The present invention relates to a process for preparing a catalyst for olefin polymerization. Specifically, the present invention relates to a process for preparing a supported metallocene catalyst capable of enhancing the operational stability during olefin polymerization by treating the supported metallocene catalyst with an antistatic agent. In the process for preparing a supported metallocene catalyst according to the embodiment of the present invention, it is possible to enhance the operational stability during olefin polymerization by treating the supported metallocene catalyst with an antistatic agent in an improved method.