Embodiments of a polyethylene polymer blend having a melt index (I.sub.2)<2 g/10 min are provided, wherein the polyethylene polymer blend comprises at least about 50% by wt. of at least one high density polyethylene resin (HDPE) having a density ≧0.950 g/cm3, a melt index (I.sub.2)<4 g/10 min; a melt flow ratio (I.sub.10/I.sub.2)≦9, and a molecular weight distribution (MWD) of about 2 to about 5; and further comprises about 1% to about 20% by wt. of at least one low density polyethylene resin (LDPE) having a density ≦0.930 g/cm3, a melt index (I.sub.2) of about 0.1 to about 10 g/min, and an MWD>3.

Embodiments of a polyethylene polymer blend having a melt index (I.sub.2)<2 g/10 min are provided, wherein the polyethylene polymer blend comprises at least about 50% by wt. of at least one high density polyethylene resin (HDPE) having a density ≧0.950 g/cm3, a melt index (I.sub.2)<4 g/10 min; a melt flow ratio (I.sub.10/I.sub.2)≦9, and a molecular weight distribution (MWD) of about 2 to about 5; and further comprises about 1% to about 20% by wt. of at least one low density polyethylene resin (LDPE) having a density ≦0.930 g/cm3, a melt index (I.sub.2) of about 0.1 to about 10 g/min, and an MWD>3.

A polyethylene composition made from or containing a polyethylene, having the following features: 1) a density from about 0.930 to about 0.945 g/cm.sup.3, determined according to ISO 1183 at 23° C.; 2) a ratio of MIF/MIP from about 10 to less than about 30; 3) a MIF from about 3 to about 25 g/10 min.; 4) a Mz equal to or greater than about 1,500,000 g/mol; and 5) a long-chain branching index, LCBI, equal to or lower than about 0.55, wherein the LCBI is the ratio of the measured mean-square radius of gyration R.sub.g, measured by GPC-MALLS, to the mean-square radius of gyration for a linear PE having the about same molecular weight of 1,000,000 g/mol.

A polyethylene composition made from or containing a polyethylene, having the following features: 1) a density from about 0.930 to about 0.945 g/cm.sup.3, determined according to ISO 1183 at 23° C.; 2) a ratio of MIF/MIP from about 10 to less than about 30; 3) a MIF from about 3 to about 25 g/10 min.; 4) a Mz equal to or greater than about 1,500,000 g/mol; and 5) a long-chain branching index, LCBI, equal to or lower than about 0.55, wherein the LCBI is the ratio of the measured mean-square radius of gyration R.sub.g, measured by GPC-MALLS, to the mean-square radius of gyration for a linear PE having the about same molecular weight of 1,000,000 g/mol.

Catalyst compositions containing a metallocene compound, a solid activator, and a co-catalyst, in which the solid activator or the supported metallocene catalyst has a d50 average particle size of 15 to 50 μm and a particle size distribution of 0.5 to 1.5, can be contacted with an olefin in a loop slurry reactor to produce an olefin polymer. A representative ethylene-based polymer produced using the catalyst composition has excellent dart impact strength and low gels, and can be characterized by a HLMI from 4 to 10 g/10 min, a density from 0.944 to 0.955 g/cm.sup.3, a higher molecular weight component with a Mn from 280,000 to 440,000 g/mol, and a lower molecular weight component with a Mw from 30,000 to 45,000 g/mol and a ratio of Mz/Mw ranging from 2.3 to 3.4.

Catalyst compositions containing a metallocene compound, a solid activator, and a co-catalyst, in which the solid activator or the supported metallocene catalyst has a d50 average particle size of 15 to 50 μm and a particle size distribution of 0.5 to 1.5, can be contacted with an olefin in a loop slurry reactor to produce an olefin polymer. A representative ethylene-based polymer produced using the catalyst composition has excellent dart impact strength and low gels, and can be characterized by a HLMI from 4 to 10 g/10 min, a density from 0.944 to 0.955 g/cm.sup.3, a higher molecular weight component with a Mn from 280,000 to 440,000 g/mol, and a lower molecular weight component with a Mw from 30,000 to 45,000 g/mol and a ratio of Mz/Mw ranging from 2.3 to 3.4.

The present invention relates to a rotomolded article, comprising at least one layer, wherein said at least one layer comprising comprises at least one metallocene-catalyzed polyethylene resin comprising at least two metallocene-catalyzed polyethylene fractions A and B; and at least one ionomer;

wherein the polyethylene resin comprises: at least 25% to at most 55% by weight of polyethylene fraction A based on the total weight of the polyethylene resin, wherein fraction A has a density at least 0.005 g/cm.sup.3 higher than the density of the polyethylene resin; and wherein the polyethylene resin has a density of at least 0.930 g/cm.sup.3 to at most 0.954 g/cm.sup.3 as measured according to ASTM D-1505 at 23° C.; a melt index MI2 of at least 1.0 g/10 min to at most 25.0 g/10 min as determined according to ISO 1133, condition D, at 190° C. and under a load of 2.16 kg.

The present invention also relates to a process for preparing said rotomolded article.

The present invention relates to a rotomolded article, comprising at least one layer, wherein said at least one layer comprising comprises at least one metallocene-catalyzed polyethylene resin comprising at least two metallocene-catalyzed polyethylene fractions A and B; and at least one ionomer;

wherein the polyethylene resin comprises: at least 25% to at most 55% by weight of polyethylene fraction A based on the total weight of the polyethylene resin, wherein fraction A has a density at least 0.005 g/cm.sup.3 higher than the density of the polyethylene resin; and wherein the polyethylene resin has a density of at least 0.930 g/cm.sup.3 to at most 0.954 g/cm.sup.3 as measured according to ASTM D-1505 at 23° C.; a melt index MI2 of at least 1.0 g/10 min to at most 25.0 g/10 min as determined according to ISO 1133, condition D, at 190° C. and under a load of 2.16 kg.

The present invention also relates to a process for preparing said rotomolded article.

A polyethylene homopolymer composition comprises: a first ethylene homopolymer having a density, d.sup.1 of from 0.930 to 0.975 g/cm.sup.3, a melt index, I.sub.2.sup.1 of from 0.01 to 10 g/10 min, and a molecular weight distribution, Mw/Mn of less than 2.5; and a second ethylene homopolymer having a density, d.sup.2 of from 0.945 to 0.980 g/cm.sup.3, a melt index, I.sub.2.sup.2 of at least 1.0 g/10 min, and a molecular weight distribution, M.sub.w/M.sub.n of less than 2.5; wherein melt index, I.sub.2.sup.2 of the second ethylene homopolymer is greater than the melt index, I.sub.2.sup.1 of the first ethylene homopolymer. The polyethylene homopolymer compositions which may be nucleated have a weight average molecular weight, M.sub.w of 75,000, a molecular weight distribution, M.sub.w/M.sub.n of less than 4.0 and may be usefully employed in molding applications, such as, for example, in compression molded closures.

A polyethylene homopolymer composition comprises: a first ethylene homopolymer having a density, d.sup.1 of from 0.930 to 0.975 g/cm.sup.3, a melt index, I.sub.2.sup.1 of from 0.01 to 10 g/10 min, and a molecular weight distribution, Mw/Mn of less than 2.5; and a second ethylene homopolymer having a density, d.sup.2 of from 0.945 to 0.980 g/cm.sup.3, a melt index, I.sub.2.sup.2 of at least 1.0 g/10 min, and a molecular weight distribution, M.sub.w/M.sub.n of less than 2.5; wherein melt index, I.sub.2.sup.2 of the second ethylene homopolymer is greater than the melt index, I.sub.2.sup.1 of the first ethylene homopolymer. The polyethylene homopolymer compositions which may be nucleated have a weight average molecular weight, M.sub.w of 75,000, a molecular weight distribution, M.sub.w/M.sub.n of less than 4.0 and may be usefully employed in molding applications, such as, for example, in compression molded closures.