Methods for determining the concentration of transition metal compounds in a solution containing more than one transition metal compound are described. Polymerization reactor systems providing real-time monitoring and control of the concentrations of the transition metal components of a multicomponent catalyst system are disclosed, as well as methods for operating such polymerization reactor systems and for improving methods of preparing the multicomponent catalyst system.

A catalyst system including two or more metallocene catalysts and processes for using the same to produce polyolefin polymer compositions are provided. The polyolefin polymer compositions have a good balance of a melt index ratio and normalized melt strength.

Disclosed herein are catalyst compositions containing bicyclic bridged metallocene compounds. These catalyst compositions can be used for the polymerization of olefins. For example, ethylene polymers produced using these catalyst compositions can be characterized by low molecular weights and high melt flow rates, and can be produced without the addition of hydrogen.

The present invention provides a metallocene supported catalyst that can prepare a polyolefin having excellent transparency even when processed into a film, as well as excellent processibility and mechanical properties, with high catalytic activity, and a method for preparing a polyolefin using the same.

Disclosed herein are ethylene-based polymers generally characterized by a Mw ranging from 70,000 to 200,000 g/mol, a ratio of Mz/Mw ranging from 1.8 to 20, an 1B parameter ranging from 0.92 to 1.05, and an ATREF profile characterized by one large peak. These polymers have the dart impact, tear strength, and optical properties of a metallocene-catalyzed LLDPE, but with improved processability, melt strength, and bubble stability, and can be used in blown film and other end-use applications.

The present invention relates to ethylene-1-hexene-1-butene terpolymer and a film including the same. The ethylene-1-hexene-1-butene terpolymer according to the present invention has an optimized range of density and melt index and includes 1-hexene and 1-butene as comonomers, and can provide a polymer showing excellent properties by regulating the content ratio of the comonomers in a certain range. Therefore, the film prepared by using the same can be usefully used because it has excellent stickiness, processibility, and falling dart impact strength which are especially suitable for stretch films.

To provide a branched propylene-based polymer that is excellent in ductility when melting, while retaining melt tension necessary for molding. A branched propylene-based polymer having the following properties (1), (2) and (3): property (1): a multi-branching index (MBI) is 0.45 or more and 1.00 or less; property (2): a strain hardening index at a strain rate (d/dt) of 1.0/see (SHI@1s.sup.1) is 0.70 or more and 3.00 or less; and property (3): a maximum drawing rate (MaxDraw) at 230 C. and a melt flow rate (MFR) satisfy a relation represented by the following formula (1-1):

[00001]$\begin{array}{cc}\left(\mathrm{MaxDraw}\right)>112\log \left(\mathrm{MFR}\right)+30& \mathrm{Formula}\left(11\right)\end{array}$

Process for producing a supported metallocene catalyst system includes: (i) preparing mixture (a) by mixing a metallocene with a cocatalyst; (ii) preparing mixture (b) by reacting an aluminium (II) with an amine (III)t;

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wherein each R6 and R10 is hydrogen or a C1-30 hydrocarbon; R7, R8, and R11 are C1-30 hydrocarbon; R9 is hydrogen or a functional moiety comprising at least one active hydrogen; (iii) providing a support material, into a reaction vessel; (iv) providing a solvent into the reaction vessel; (v) supplying mixture (a) and mixture (b) to the reaction vessel; (vi) subjecting the contents of the reaction vessel to a temperature of >60? C. for a period of >3 hrs to obtain a supported catalyst system; and (vii) removing the solvent from the supported catalyst system. Such process allows for the production of a supported metallocene catalyst system having reduced fouling in olefin polymerisation.

Disclosed herein are ethylene-based polymers generally characterized by a Mw ranging from 70,000 to 200,000 g/mol, a ratio of Mz/Mw ranging from 1.8 to 20, an IB parameter ranging from 0.92 to 1.05, and an ATREF profile characterized by one large peak. These polymers have the dart impact, tear strength, and optical properties of a metallocene-catalyzed LLDPE, but with improved processability, melt strength, and bubble stability, and can be used in blown film and other end-use applications.

The present invention relates to a method for preparing polyolefin that can easily and effectively prepare polyolefin having high molecular weight and various molecular weight distributions, which was difficult to prepare using the existing metallocene catalyst, and polyolefin prepared thereby. The method for preparing polyolefin comprises the step of polymerizing olefin monomers, in the presence of a metallocene supported catalyst wherein a metallocene compound having a specific chemical structure is supported in a carrier, and hydrogen gas.