A system and method of producing polyethylene, including: polymerizing ethylene in presence of a catalyst system in a reactor to form polyethylene, wherein the catalyst system includes a first catalyst and a second catalyst; and adjusting reactor conditions and an amount of the second catalyst fed to the reactor to control melt index (MI), density, and melt flow ratio (MFR) of the polyethylene.

A system and method of producing polyethylene, including: polymerizing ethylene in presence of a catalyst system in a reactor to form polyethylene, wherein the catalyst system includes a first catalyst and a second catalyst; and adjusting reactor conditions and an amount of the second catalyst fed to the reactor to control melt index (MI), density, and melt flow ratio (MFR) of the polyethylene.

A terpolymer compositions made from or containing: A) From 80 wt % to 97 wt %; of a first propylene, ethylene, 1-butene terpolymer having: i) the content of ethylene derived units ranging from 0.5 wt % to 3.2 wt %; ii) the content of 1-butene derived units ranging from 7.2 wt % to 14.8 wt %; and B) From 20 wt % to 3 wt %; of a second propylene, ethylene, 1-butene terpolymer having: i) the content of ethylene derived units ranging from 0.5 wt % to 3.2 wt %; ii) the content of 1-butene derived units ranging from 14.4 wt % to 26.5 wt %; and the terpolymer composition having the melt flow rate, MFR, measured according to ISO 1133 at 230° C. with a load of 2.16 kg, ranging from 3.0 g/10 min to 20.0 g/10 min; the sum of the amounts of A) and B) being 100 wt %.

A terpolymer compositions made from or containing: A) From 80 wt % to 97 wt %; of a first propylene, ethylene, 1-butene terpolymer having: i) the content of ethylene derived units ranging from 0.5 wt % to 3.2 wt %; ii) the content of 1-butene derived units ranging from 7.2 wt % to 14.8 wt %; and B) From 20 wt % to 3 wt %; of a second propylene, ethylene, 1-butene terpolymer having: i) the content of ethylene derived units ranging from 0.5 wt % to 3.2 wt %; ii) the content of 1-butene derived units ranging from 14.4 wt % to 26.5 wt %; and the terpolymer composition having the melt flow rate, MFR, measured according to ISO 1133 at 230° C. with a load of 2.16 kg, ranging from 3.0 g/10 min to 20.0 g/10 min; the sum of the amounts of A) and B) being 100 wt %.

A terpolymer compositions made from or containing: A) From 80 wt % to 97 wt %; of a first propylene, ethylene, 1-butene terpolymer having: i) the content of ethylene derived units ranging from 0.5 wt % to 3.2 wt %; ii) the content of 1-butene derived units ranging from 7.2 wt % to 14.8 wt %; and B) From 20 wt % to 3 wt %; of a second propylene, ethylene, 1-butene terpolymer having: i) the content of ethylene derived units ranging from 0.5 wt % to 3.2 wt %; ii) the content of 1-butene derived units ranging from 14.4 wt % to 26.5 wt %; and the terpolymer composition having the melt flow rate, MFR, measured according to ISO 1133 at 230° C. with a load of 2.16 kg, ranging from 3.0 g/10 min to 20.0 g/10 min; the sum of the amounts of A) and B) being 100 wt %.

A heterophasic copolymer composition obtained by a process comprising polymerising in multiple steps and multiple polymerisation reactors propylene monomer and a comonomer selected from ethylene, alpha-olefins having 4 to 10 carbon atoms and their mixtures, in the presence of an olefin polymerisation catalyst comprising a solid catalyst component and a co-catalyst, wherein the solid catalyst component comprises titanium, magnesium, halogen and an internal donor of the formula (I):

##STR00001##

wherein R.sub.1 and R.sub.2 are the same or different being a linear or branched C.sub.1-C.sub.12-alkyl group and R is hydrogen or a linear, branched or cyclic C.sub.1 to C.sub.12-alkyl.

A heterophasic copolymer composition obtained by a process comprising polymerising in multiple steps and multiple polymerisation reactors propylene monomer and a comonomer selected from ethylene, alpha-olefins having 4 to 10 carbon atoms and their mixtures, in the presence of an olefin polymerisation catalyst comprising a solid catalyst component and a co-catalyst, wherein the solid catalyst component comprises titanium, magnesium, halogen and an internal donor of the formula (I):

##STR00001##

wherein R.sub.1 and R.sub.2 are the same or different being a linear or branched C.sub.1-C.sub.12-alkyl group and R is hydrogen or a linear, branched or cyclic C.sub.1 to C.sub.12-alkyl.

Embodiments of polyethylene compositions and articles comprising polyethylene compositions are disclosed. The polyethylene compositions may include a first polyethylene fraction area defined by an area in the elution profile in a temperature range of 70° C. to 97° C. via improved comonomer composition distribution (iCCD) analysis method; a first peak in the temperature range of 70° C. to 97° C. in the elution profile; a second polyethylene fraction area defined by an area in the elution profile in a temperature range of 97° C. to 110° C.; and a second peak in the temperature range of 97° C. to 110° C. The polyethylene composition may have a density of 0.935 g/cm.sup.3 to 0.955 g/cm.sup.3 and a melt index (I.sub.2) of 1.0 g/10 minutes to 10.0 g/10 minutes. A ratio of the first polyethylene fraction area to the second polyethylene fraction area may be less than 2.0.

Embodiments of polyethylene compositions and articles comprising polyethylene compositions are disclosed. The polyethylene compositions may include a first polyethylene fraction area defined by an area in the elution profile in a temperature range of 70° C. to 97° C. via improved comonomer composition distribution (iCCD) analysis method; a first peak in the temperature range of 70° C. to 97° C. in the elution profile; a second polyethylene fraction area defined by an area in the elution profile in a temperature range of 97° C. to 110° C.; and a second peak in the temperature range of 97° C. to 110° C. The polyethylene composition may have a density of 0.935 g/cm.sup.3 to 0.955 g/cm.sup.3 and a melt index (I.sub.2) of 1.0 g/10 minutes to 10.0 g/10 minutes. A ratio of the first polyethylene fraction area to the second polyethylene fraction area may be less than 2.0.

Provided in this disclosure are zirconium and hafnium complexes that contain 1) a cyclopentadienyl ligand; 2) an adamantyl-phosphinimine ligand; and 3) at least one other ligand. The use of such a complex, in combination with an activator, as an olefin polymerization catalyst is demonstrated. The catalysts are effective for the copolymerization of ethylene with an alpha olefin (such as 1-butene, 1-hexene, or 1-octene).