A method is provided to control the short chain branching (SCB) distribution of an ethylene-butene (EB) polyethylene resin that is prepared in a gas phase polymerization process using a specific type of magnesium-titanium Ziegler Natta catalyst. The method allows the level of short chain branching to be increased in the low molecular weight fraction of the resin by increasing the polymerization residence time. The polymers that are produced in accordance with this invention may be useful for the preparation of cast films and blown films, especially for stretch film applications.

A method is provided to control the short chain branching (SCB) distribution of an ethylene-butene (EB) polyethylene resin that is prepared in a gas phase polymerization process using a specific type of magnesium-titanium Ziegler Natta catalyst. The method allows the level of short chain branching to be increased in the low molecular weight fraction of the resin by increasing the polymerization residence time. The polymers that are produced in accordance with this invention may be useful for the preparation of cast films and blown films, especially for stretch film applications.

The various embodiments of the invention provide, a magnesium dichloride support and the magnesium titanium polymerization procatalyst made therefrom, and methods for making and using the same.

The various embodiments of the invention provide, a magnesium dichloride support and the magnesium titanium polymerization procatalyst made therefrom, and methods for making and using the same.

Disclosed are a catalyst component for olefin polymerization comprising titanium, magnesium, a halogen, internal donors, in combination with a silane and oxalic acid diamides of the following formula:

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An olefin polymerization catalyst system consisting of the solid catalyst component, an organoaluminum compound, and an optional external electron donor compound is also disclosed. Employment of both oxalic acid diamides and silane component in the presence of internal electron donors as an elements of solid Ziegler-Natta type catalyst composition enhances stereo-specificity while maintaining excellent catalyst activity and hydrogen response, in which the modified catalyst composition produces polypropylene with good productivity and higher stereo-specificity than catalyst composition without such modification.

The present disclosure generally relates to ethylene alpha-olefin copolymers and methods of making ethylene alpha-olefin copolymers. The ethylene alpha-olefin copolymers may have a density of about 0.915 g/mL to about 0.918 g/mL, a rheological polydispersity index greater than 0.8, a melt index of about 0.4 dg/10 min to about 2.0 dg/10 min, and/or a CEF T.sub.50 of 84 C. or less. The ethylene alpha-olefin copolymers may be made by combining an ethylene monomer and one or more alpha-olefin monomers in the presence of a catalyst, such as a Ziegler-Natta catalyst.

The present disclosure generally relates to ethylene alpha-olefin copolymers and methods of making ethylene alpha-olefin copolymers. The ethylene alpha-olefin copolymers may have a density of about 0.915 g/mL to about 0.918 g/mL, a rheological polydispersity index greater than 0.8, a melt index of about 0.4 dg/10 min to about 2.0 dg/10 min, and/or a CEF T.sub.50 of 84 C. or less. The ethylene alpha-olefin copolymers may be made by combining an ethylene monomer and one or more alpha-olefin monomers in the presence of a catalyst, such as a Ziegler-Natta catalyst.

The present invention relates to a process for preparing a catalyst component for polymerization of an olefin comprising the steps of: i) contacting a compound R.sup.9.sub.zMgX.sub.2-z wherein R.sup.9 is aromatic, aliphatic or cyclo-aliphatic group containing up to 20 carbon atoms, X is a halide, and z is in a range of larger than 0 and smaller than 2, with an alkoxy- or aryloxy-containing silane compound to given a first intermediate reaction product; ii) contacting the first intermediate reaction product with at least one activating compound selected from the group formed by electron donors and compounds of formula M(OR.sup.10).sub.v-w(OR.sup.11).sub.w, wherein M can be Ti, Zr, Hf, Al or Si, and M(OR.sup.10).sub.v-w(R.sup.11).sub.w, wherein M is Si, each R.sup.10 and R.sup.11, independently, represent an alkyl, alkenyl or aryl group, v is the valency of M, v being either 3 or 4, and w is smaller than v, to give a second intermediate reaction product; and iii) contacting the second intermediate reaction product with a halogen-containing Ti-compound, a monoester as activating agent, a 1,3-diether as an internal electron donor, and optionally a diester as an additional internal electron donor.

The present invention relates to a process for preparing a catalyst component for polymerization of an olefin comprising the steps of: i) contacting a compound R.sup.9.sub.zMgX.sub.2-z wherein R.sup.9 is aromatic, aliphatic or cyclo-aliphatic group containing up to 20 carbon atoms, X is a halide, and z is in a range of larger than 0 and smaller than 2, with an alkoxy- or aryloxy-containing silane compound to given a first intermediate reaction product; ii) contacting the first intermediate reaction product with at least one activating compound selected from the group formed by electron donors and compounds of formula M(OR.sup.10).sub.v-w(OR.sup.11).sub.w, wherein M can be Ti, Zr, Hf, Al or Si, and M(OR.sup.10).sub.v-w(R.sup.11).sub.w, wherein M is Si, each R.sup.10 and R.sup.11, independently, represent an alkyl, alkenyl or aryl group, v is the valency of M, v being either 3 or 4, and w is smaller than v, to give a second intermediate reaction product; and iii) contacting the second intermediate reaction product with a halogen-containing Ti-compound, a monoester as activating agent, a 1,3-diether as an internal electron donor, and optionally a diester as an additional internal electron donor.

The instant invention provides a polyethylene composition and process for polymerizing the same.

The polyethylene composition according to the present invention comprises the polymerization reaction of ethylene and optionally one or more -olefin comonomers in the presence of a catalyst system, wherein said polyethylene composition comprises at least 2 or more molecular weight distributions, measured via triple detector GPC low angle laser light scattering (GPC-LALLS), described in further details hereinbelow, wherein each molecular weight distribution has a peak, and wherein measured detector response of peak 1 divided by the measured detector response of peak 2 is in the range of from 0.50 to 0.79, for example from 0.55 to 0.77.