C08F2420/01

Ethylene homopolymers with a reverse short chain branch distribution

Disclosed herein are ethylene homopolymers generally characterized by a density of less than 0.94 g/cm.sup.3 and an inverse short chain branch distribution. These homopolymers can be further characterized by a ratio of Mw/Mn from 2 to 100, a number of short chain branches from 2 to 20 short chain branches per 1000 total carbon atoms, and wherein at least 50% of the short chain branches are methyl branches.

Silica-coated alumina activator-supports for metallocene catalyst compositions

Silica-coated alumina activator-supports, and catalyst compositions containing these activator-supports, are disclosed. Methods also are provided for preparing silica-coated alumina activator-supports, for preparing catalyst compositions, and for using the catalyst compositions to polymerize olefins.

Metallocene catalyst compositions and polymerization process therewith

This invention relates bisindenyl metallocene catalyst compounds having long (at least 4 carbon atoms) linear alkyl groups substituted at the two position and substituted or unsubstituted aryl groups at the four position and process using such catalyst compounds, particularly in the solution process at higher temperatures.

Multiple non-coordinating anion activators for propylene-ethylene-diene monomer polymerization reactions

This invention relates to production of propylene-predominant copolymers using a transition metal complex and at least two different non-coordinating anion activators. An olefinic feed comprising a C.sub.3-C.sub.40 alpha olefin, ethylene, and a diene monomer is contacted under polymerization reaction conditions with a catalyst system comprising a first non-coordinating anion activator, a second non-coordinating borate activator differing from the first non-coordinating anion activator, and a transition metal complex comprising a tetrahydro-s-indacenyl or tetrahydro-as-indacenyl group bound to a group 3-6 transition metal. A molar ratio of the first non-coordinating anion activator to the second non-coordinating anion activator is sufficient to produce a melt flow rate under the polymerization reaction conditions for the resulting copolymer of about 30 g/10 min or below as determined by ASTM D-1238 (230 C., 2.16 kg).

METHOD TO PREPARE ETHYLENE COPOLYMERS

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:

##STR00001##

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.

Low density polyolefin resins with low molecular weight and high molecular weight components, and films made therefrom

Disclosed herein are ethylene-based polymers produced using dual metallocene catalyst systems. These polymers have low densities, high molecular weights, and broad molecular weight distributions, as well as having the majority of the long chain branches in the lower molecular weight component of the polymer, and the majority of the short chain branches in the higher molecular weight component of the polymer. Films produced from these polymers have improved impact and puncture resistance.

CATALYSTS FOR OLEFIN POLYMERIZATION

New bisindenyl ligand complexes and catalysts comprising those complexes. The invention is directed to improving the manufacturing of specific C1-symmetric bisindenyl complexes by modifying one of the indenyl ligands in order to improve the selectivity of the complex synthesis towards the desired anti-isomer, increase the yield and simplify the purification of the complex. The invention also relates to the use of the new bisindenyl metallocene catalysts for the production of polypropylene homopolymers or propylene copolymers.

Processes for producing high propylene content PEDM having low glass transition temperatures using tetrahydroindacenyl catalyst systems

The present disclosure provides methods for producing an olefin polymer by contacting a C.sub.3-C.sub.40 olefin, ethylene and a diene with a catalyst system including an activator and a metallocene catalyst compound comprising a substituted or unsubstituted indacenyl group and obtaining a C.sub.3-C.sub.40 olefin-ethylene-diene terpolymer typically comprising from 30 to 55 mol % ethylene, from 69.09 to 45 mol % C.sub.3 to C.sub.40 comonomer, and from 0.01 to 7 mol % diene wherein the Tg of the terpolymer is 28 C. or less. Preferably, a propylene-ethylene-ethylidene norbornene is obtained.

Propylene-diene copolymer resin having excellent melt tension

Disclosed is a propylene-diene copolymer resin having excellent melt tension, with improved melt strength, high molecular weight and broad molecular weight distribution by using a specific metallocene catalyst system. The present invention provides a propylene-diene copolymer resin produced by polymerizing propylene and a diene compound of C4-C20 by using a metallocene catalyst system, wherein the propylene-diene copolymer resin has the melt index (2.16 kg load at 230 C.) of 0.1-100 g/10 min and the melt tension (advanced rheometric expansion system (ARES)) of 5-100 g.

Supported hybrid catalyst

The present disclosure provides a supported hybrid catalyst which facilitates the preparation of polyolefins having improved bubble stability and exhibiting excellent processability for a blown film while maintaining high transparent haze and improved melt strength, and a method for preparing the same.