Embodiments of the present disclosure are directed towards method for modifying a polymer flow index. As an example, a method for modifying a polymer flow index can include providing monomers to a polymerization reactor, providing a chromium catalyst to the polymerization reactor, and providing an active amount of a flow index modifier to the polymerization reactor, wherein the flow index modifier is selected from carbon dioxide, carbon monoxide, 2,4-hexadiene, and combinations thereof.

A unimodal ethylene-co-1-hexene copolymer that, when in melted form at 190 degrees Celsius, is characterized by a unique melt property space defined by combination of melt elasticity and complex viscosity ratio (shear thinning)properties. A blown film consisting essentially of the unimodal ethylene-co-1-hexene copolymer. A method of synthesizing the unimodal ethylene-co-1-hexene copolymer. A method of making the blown film. A manufactured article comprising the unimodal ethylene-co-1-hexene copolymer.

A unimodal ethylene-co-1-hexene copolymer that, when in melted form at 190 degrees Celsius, is characterized by a unique melt property space defined by combination of melt elasticity and complex viscosity ratio (shear thinning)properties. A blown film consisting essentially of the unimodal ethylene-co-1-hexene copolymer. A method of synthesizing the unimodal ethylene-co-1-hexene copolymer. A method of making the blown film. A manufactured article comprising the unimodal ethylene-co-1-hexene copolymer.

An activator-nucleator formulation comprising an activating effective amount of (A) an alkylaluminum(chloride) compound (compound (A)); and a nucleating effective amount of a compound (B) selected from at least one of compounds (B1) to (B3): (B1) calcium (1R,2S)-cis-cyclohexane-1,2-dicarboxylate (1:1); (B2) calcium stearate (1:2), and (B3) zinc stearate (1:2); wherein the compound (A) is effective for activating a Ziegler-Natta procatalyst to give a Ziegler-Natta catalyst; and wherein the compound (B) is effective for lowering isothermal crystallization peak time period of a semicrystalline polyethylene polymer made in a polymerization process by the Ziegler-Natta catalyst. A method of polymerizing ethylene, and optionally 0, 1, or more alpha-olefin comonomers, in a polymerization process conducted in a polymerization reactor, the method comprising contacting ethylene, and optionally 0, 1, or more alpha-olefin comonomers, with the Ziegler-Natta catalyst system to give a semicrystalline polyethylene polymer. The semicrystalline polyethylene polymer made by the method of polymerizing.

An activator-nucleator formulation comprising an activating effective amount of (A) an alkylaluminum(chloride) compound (compound (A)); and a nucleating effective amount of a compound (B) selected from at least one of compounds (B1) to (B3): (B1) calcium (1R,2S)-cis-cyclohexane-1,2-dicarboxylate (1:1); (B2) calcium stearate (1:2), and (B3) zinc stearate (1:2); wherein the compound (A) is effective for activating a Ziegler-Natta procatalyst to give a Ziegler-Natta catalyst; and wherein the compound (B) is effective for lowering isothermal crystallization peak time period of a semicrystalline polyethylene polymer made in a polymerization process by the Ziegler-Natta catalyst. A method of polymerizing ethylene, and optionally 0, 1, or more alpha-olefin comonomers, in a polymerization process conducted in a polymerization reactor, the method comprising contacting ethylene, and optionally 0, 1, or more alpha-olefin comonomers, with the Ziegler-Natta catalyst system to give a semicrystalline polyethylene polymer. The semicrystalline polyethylene polymer made by the method of polymerizing.

A composition comprising a high molecular weight, chromium catalyzed ethylene copolymer (also referred to as a polyethylene resin), a nucleating agent and zinc oxide.

A composition comprising a high molecular weight, chromium catalyzed ethylene copolymer (also referred to as a polyethylene resin), a nucleating agent and zinc oxide.

An organometallic complex, a catalyst composition employing the same, and a method for preparing polyolefin are provided. The organometallic compound has a structure represented by Formula (I)

##STR00001##

, wherein M is Ti, Zr, or Hf; X is —O—, or —NR.sup.6—; R.sup.1 and R.sup.2 are independently hydrogen, C.sub.1-6 alkyl group, C.sub.6-12 aryl group, or R.sup.1 and R.sup.2 are combined with the carbon atoms, to which they are attached, to form an C.sub.6-12 aryl moiety; R.sup.3, R.sup.4 and R.sup.5 are independently fluoride, chloride, bromide, C.sub.1-6 alkyl group, C.sub.6-12 aryl group, C.sub.3-6 hetero aryl group, C.sub.7-13 aryl alkyl group or C.sub.7-12 alkyl aryl group; and R.sup.6 is hydrogen, C.sub.6-12 aryl group or C.sub.7-12 alkyl aryl group.

Sulfated bentonite compositions are characterized by a total pore volume from 0.4 to 1 mL/g, a total BET surface area from 200 to 400 m.sup.2/g, and an average pore diameter from 55 to 100 Angstroms. The sulfated bentonite compositions also can be characterized by a d50 average particle size in a range from 15 to 50 .Math.m and a ratio of d90/d10 from 3 to 15. The sulfated bentonite compositions can contain a sulfated bentonite and from 10 to 90 wt. % of colloidal particles, or the sulfated bentonite compositions can contain a sulfated bentonite and from 0.2 to 10 mmol/g of zinc and/or phosphorus. These compositions can be utilized in metallocene catalyst systems to produce ethylene based polymers.

A process for the preparation of an ultra-high molecular weight ethylene homopolymer having a MFR.sub.21 of 0.01 g/10 min or less, said process comprising: (I) prepolymerising at least ethylene at a temperature of 0 to 90° C. in the presence of a heterogeneous Ziegler Natta catalyst to prepare an ethylene prepolymer having an Mw of 40,000 to 600,000 g/mol; and thereafter in the presence of the prepolymer and said catalyst; (II) polymerising ethylene at a temperature of 55° C. or less, such as 20 to 55° C., to prepare said UHMW ethylene homopolymer; wherein the UHMW ethylene homopolymer comprises up to 8 wt. % of said prepolymer.