The present invention relates to a method for preparing a high activity olefin polymerization catalyst, which is easy to be produced, reducing complicated steps, and can be produced at low temperature, wherein said method comprising the following steps: • (a) adding a magnesium halide into an alcohol solvent; • (b) precipitating the solution obtained from (a) in a solution of an organic solvent containing an organo compound of group III element; • (c) adding a titanium compound into the mixture obtained from (b) to obtain a catalyst; • (d) treating the catalyst obtained from (c) with an organoaluminium compound at a temperature ranging from 0 to 60° C. for 2 to 5 hours, wherein the mole ratio of aluminium to titanium (Al/Ti) for treatment is in a range of 1 to 30.

The present invention relates to a rotomolded article, comprising at least one metallocene-catalyzed polyethylene resin comprising at least two metallocene-catalyzed polyethylene fractions A and B, 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 melt index MI2 of at least 25.0 g/10 min as determined according to ISO 1133, condition D, at 190° C. and under a load of 2.16 kg, and 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 0.938 g/cm.sup.3 to at most 0.950 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 metallocene-catalyzed polyethylene resin comprising at least two metallocene-catalyzed polyethylene fractions A and B, 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 melt index MI2 of at least 25.0 g/10 min as determined according to ISO 1133, condition D, at 190° C. and under a load of 2.16 kg, and 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 0.938 g/cm.sup.3 to at most 0.950 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.

I, II, III and IV,

##STR00001## wherein Y is a C.sub.1-C.sub.20 linear, branched or cyclic hydrocarbyl group, or a C.sub.6-C.sub.30 aryl or substituted aryl group; L is an electron-donating ligand; A is an element selected from Group 15 or 16; R is a C.sub.1-C.sub.30 alkyl, aryl, or substituted aryl group; n is an integer from 1 to 3; m is an integer from 1 to 4; B is a boron atom; M is selected from lanthanides or transition metals from group 3, 4, 5 or 6; X is an anionic ligand to M and z is the valence of M minus 2; and a catalyst comprising a 2-indenyl metallocene complex, a ligand precursor, a process for preparation of a ligand precursor, a process for preparation of olefin polymers in the presence of 2-indenyl metallocene complexes, articles comprising an olefin polymer, and methods of making the articles.

The present invention relates to a polyethylene composition comprising a base resin comprising a low molecular weight ethylene polymer component and a high molecular weight ethylene polymer component, wherein the high molecular weight ethylene polymer component has a higher weight average molecular weight than the low molecular weight ethylene polymer component, wherein the base resin has a density of at least 958.0 kg/m.sup.3, and the polyethylene composition a melt flow rate MFR.sub.2 (190° C., 2.16 kg) of from 0.50 to 0.80 g/10 min and a molecular weight distribution being the ratio of the weight average molecular weight and the number average molecular weight, Mw/Mn, of from 10.0 to 15.0, a process for producing said polyethylene composition, an article comprising said polyethylene composition and the use of said polyethylene composition for the production of a film.

The present invention relates to a polyethylene composition comprising a base resin comprising a low molecular weight ethylene polymer component and a high molecular weight ethylene polymer component, wherein the high molecular weight ethylene polymer component has a higher weight average molecular weight than the low molecular weight ethylene polymer component, wherein the base resin has a density of at least 958.0 kg/m.sup.3, and the polyethylene composition a melt flow rate MFR.sub.2 (190° C., 2.16 kg) of from 0.50 to 0.80 g/10 min and a molecular weight distribution being the ratio of the weight average molecular weight and the number average molecular weight, Mw/Mn, of from 10.0 to 15.0, a process for producing said polyethylene composition, an article comprising said polyethylene composition and the use of said polyethylene composition for the production of a film.

An ethylene-based resin comprising a high molecular weight component and a low molecular weight component, wherein the high molecular weight component comprises an ethylene/alpha-olefin copolymer or ethylene homopolymer, and has a density ranging from 0.940 g/cc to 0.960 g/cc, and a high load melt index (I21.6) ranging from 4 g/10 min to 15 g/10 min, and wherein the ethylene-based resin has: an overall density ranging from greater than 0.955 to less than or equal to 0.970 g/cc, an overall melt index (I2.16) ranging from 0.5 g/10 min to 7 g/10 min, and less than 0.2 vinyls per 1000 carbon atoms.

An ethylene-based resin comprising a high molecular weight component and a low molecular weight component, wherein the high molecular weight component comprises an ethylene/alpha-olefin copolymer or ethylene homopolymer, and has a density ranging from 0.940 g/cc to 0.960 g/cc, and a high load melt index (I21.6) ranging from 4 g/10 min to 15 g/10 min, and wherein the ethylene-based resin has: an overall density ranging from greater than 0.955 to less than or equal to 0.970 g/cc, an overall melt index (I2.16) ranging from 0.5 g/10 min to 7 g/10 min, and less than 0.2 vinyls per 1000 carbon atoms.

The present invention relates to an injection-molded article, comprising at least one metallocene-catalyzed polyethylene resin comprising at least two metallocene-catalyzed polyethylene fractions A and B, wherein the at least one metallocene-catalyzed polyethylene resin comprises: at least 40% to at most 50% by weight of polyethylene fraction A based on the total weight of the at least one metallocene-catalyzed polyethylene resin, wherein fraction A has a melt index MI2 of at least 100.0 g/10 min as determined according to ISO 1133, condition D, at 190° C. and under a load of 2.16 kg; and
wherein the at least one metallocene-catalyzed polyethylene resin has a density of at least 0.940 g/cm.sup.3 to at most 0.950 g/cm.sup.3 as measured on pellets according to ISO 1183 at 23° C.; a melt index MI2 of at least 1.4 g/10 min to at most 2.5 g/10 min as measured on pellets 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 injection-molded article, comprising the steps of a) providing at least one metallocene-catalyzed polyethylene resin as described herein; and b) injection-molding said polyethylene resin into an article.

The present invention relates to an injection-molded article, comprising at least one metallocene-catalyzed polyethylene resin comprising at least two metallocene-catalyzed polyethylene fractions A and B, wherein the at least one metallocene-catalyzed polyethylene resin comprises: at least 40% to at most 50% by weight of polyethylene fraction A based on the total weight of the at least one metallocene-catalyzed polyethylene resin, wherein fraction A has a melt index MI2 of at least 100.0 g/10 min as determined according to ISO 1133, condition D, at 190° C. and under a load of 2.16 kg; and
wherein the at least one metallocene-catalyzed polyethylene resin has a density of at least 0.940 g/cm.sup.3 to at most 0.950 g/cm.sup.3 as measured on pellets according to ISO 1183 at 23° C.; a melt index MI2 of at least 1.4 g/10 min to at most 2.5 g/10 min as measured on pellets 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 injection-molded article, comprising the steps of a) providing at least one metallocene-catalyzed polyethylene resin as described herein; and b) injection-molding said polyethylene resin into an article.