The present disclosure provides a catalyst system made from or containing: (A) a solid catalyst component made from or containing (i) a titanium compound supported on a magnesium dichloride; (B) an aluminum alkyl compound; and (C) a halogenated organic ester of formula A-COOR, wherein R is a C.sub.1-C.sub.10 hydrocarbon group and A is a C.sub.1-C.sub.15 saturated or unsaturated hydrocarbon group in which at least one of the hydrogen atoms is replaced by a chlorine atom. The present disclosure also provides a process for preparing an olefinic polymer, including a polymerization step of polymerizing an olefin in the presence of the catalyst system. The present disclosure also provides an olefinic polymer made therefrom.

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.

Ethylene/1-butene copolymers made with a single site catalyst system have high melt strength and good processability.

The present invention relates to a process for the production of a polyethylene by polymerisation of a reaction mixture comprising ethylene in the presence a catalyst system and an antistatic agent according to formula I: (I) wherein R1, R2 and R3 stand for a moiety according to formula II or a hydrocarbon moiety having 1 to 20 carbon atoms (II) wherein each of R4, R5 and R6 may be the same or different, and wherein each of R4, R5 and R6 is a hydrocarbon moiety having 1 to 10 carbon atoms, and wherein at least one of R1, R2 and R3 is a moiety according to formula II. Such process allows for the reduction of sheeting in the polymerisation reactor without compromising the polymerisation reaction kinetics.

##STR00001##

Disclosed is an antistatic agent for a metallocene olefin polymerization process and a polymerization method using the same, by which discontinuity event due to sheeting or drooling occurring in the olefin polymerization process can be effectively reduced, enabling continuous operation for a long time, and the obtained final product can be applied to various applications including food contact use. The present disclosure includes an olefin polymerization method, which comprises forming a mixture in which an antistatic agent containing diglycerol oleate is mixed with a low molecular weight hydrocarbon, supplying the antistatic agent mixture and a metallocene-based catalyst composition comprising a metallocene catalyst and aluminoxane to two or more polymerization reactors, and polymerizing one or more alpha-olefins in the presence of the antistatic agent mixture and catalyst composition.

A catalyst composition for polymerizing a polyolefin having excellent processability and impact strength, a process for producing a polyolefin and a polyolefin resin thereof are disclosed. The catalyst composition comprises at least one first organometallic compound of following formula 1; at least one second organometallic compound of following formula 2; and aluminoxane. The polyolefin resin satisfies following properties (i) to (iv) and (vi), (i) melt flow index (ASTM D1238), measured at 190° C., under a load of 2.16 kg: 0.1 to 1.5 g/10 min, (ii) density: 910 to 930 kg/m.sup.3, (iii) the ratio (Mw/Mn), as measured by gel permeation chromatography (GPC): 3.0 to 7.0, (iv) the ratio (Mz/Mw), as measured by GPC: 2.2 to 4.5, and (vi) when the TREF curve of multimodal distribution is deconvoluted, the area of TREF curve having a peak at 50 to 74° C. is 40 to 75% of the total area of the TREF curve.

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 comprises the following formula:

##STR00001##

wherein each R.sup.3 or R.sup.4 is independently H, a hydrocarbyl group, a substituted hydrocarbyl group, or a heteroatom group, wherein each R.sup.3 or R.sup.4 may be the same or different, and each X is independently a leaving group selected from a labile hydrocarbyl, a substituted hydrocarbyl, a heteroatom group, or a divalent radical that links to an R.sup.3 group.

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 producing a polyolefin in which the formation of gels is suppressed. In the process for preparing a supported metallocene catalyst according to an embodiment of the present invention, it is treated with a metallic stearate after a transition metal compound has been supported, which suppresses the formation of a macromolecular polyolefin. Thus, a polyolefin with minimal gel formation can be prepared.

There are provided a polyethylene capable of improving tensile strength while maintaining excellent processability and Mooney viscosity characteristics when preparing a chlorinated polyethylene compound by implementing a molecular structure having a low content of low molecular weight and a high content of high molecular weight, and a chlorinated polyethylene prepared using the same.

The present invention relates to a branched modifier and a composition comprising more than 25 wt % (based on the weight of the composition) of one or more linear ethylene polymers having a g′.sub.vis of 0.97 or more and an Mw of 20,000 g/mol or more and at least 0.1 wt % of a branched modifier where the modifier has a) a g′.sub.vis of 0.70 or less; b) an Mw of 100,000 g/mol or more; c) an Mw/Mn of 4.0 or more; d) a shear thinning ratio of 110 or more, e) a melt strength of 10 cN or more; f) a complex viscosity at 0.1 rad/sec at 190° C. of at least 130,000 Pa.Math.s; and g) a phase angle of Z° or less where Z=138.3G*.sup.(−0.142), where G* is the complex modulus reported in Pascals measured at 190° C. and the phase angle units are reported in degrees, wherein the G* is from 1,000 to 1,000,000 Pa.