The present invention relates to a reactor system for a multimodal polyethylene polymerization process, comprising; (a) a first reactor; (b) a hydrogen removal unit arranged between the first reactor and a second reactor comprising at least one vessel connected with a depressurization equipment, preferably selected from vacuum pump, compressor, blower, ejector or a combination thereof, the depressurization equipment allowing to adjust an operating pressure to a pressure in a range of 100-200 kPa (abs); (c) the second reactor; and (d) a third reactor and use thereof as a sheet.

The present invention relates to a reactor system for a multimodal polyethylene polymerization process, comprising; (a) a first reactor; (b) a hydrogen removal unit arranged between the first reactor and a second reactor comprising at least one vessel connected with a depressurization equipment, preferably selected from vacuum pump, compressor, blower, ejector or a combination thereof, the depressurization equipment allowing to adjust an operating pressure to a pressure in a range of 100-200 kPa (abs); (c) the second reactor; and (d) a third reactor and use thereof as a sheet.

The present invention relates to a polyethylene resin suitable for preparing moulded articles, such as caps and closures. The invention provides in particular a polyethylene resin comprising at least two polyethylene fractions A and B, wherein said polyethylene resin has a melt index (MI2), of at least 3.0 g/10 min to at most 5.5 g/10 min as measured according to ISO 1133, condition D, at 190° C. and under a load of 2.16 kg, and a density of at least 0.955 g/cm.sup.3 to at most 0.965 g/cm.sup.3 as measured according to ISO 1183 at 23° C., and a molecular weight distribution M.sub.w/M.sub.n which is at most 7.0, as determined by gel permeation chromatography, with M.sub.w being the weight-average molecular weight and M.sub.n being the number-average molecular weight; and wherein said polyethylene fraction A has a high load melt index (HLMI), as measured according to ISO 1133:1997 condition G at 190° C. and under a load of 21.6 kg, of at least 10.5 and a melt index (MI2) of at least 0.5 g/10 min to at most 1.5 g/10 min as measured according to ISO 1133, condition D, at 190° C. and under a load of 2.16 kg. The invention further relates to a process for preparing said polyethylene resin, to a cap or closure comprising said polyethylene, and to a process for producing such a cap or closure.

The present invention relates to a polyethylene resin suitable for preparing moulded articles, such as caps and closures. The invention provides in particular a polyethylene resin comprising at least two polyethylene fractions A and B, wherein said polyethylene resin has a melt index (MI2), of at least 3.0 g/10 min to at most 5.5 g/10 min as measured according to ISO 1133, condition D, at 190° C. and under a load of 2.16 kg, and a density of at least 0.955 g/cm.sup.3 to at most 0.965 g/cm.sup.3 as measured according to ISO 1183 at 23° C., and a molecular weight distribution M.sub.w/M.sub.n which is at most 7.0, as determined by gel permeation chromatography, with M.sub.w being the weight-average molecular weight and M.sub.n being the number-average molecular weight; and wherein said polyethylene fraction A has a high load melt index (HLMI), as measured according to ISO 1133:1997 condition G at 190° C. and under a load of 21.6 kg, of at least 10.5 and a melt index (MI2) of at least 0.5 g/10 min to at most 1.5 g/10 min as measured according to ISO 1133, condition D, at 190° C. and under a load of 2.16 kg. The invention further relates to a process for preparing said polyethylene resin, to a cap or closure comprising said polyethylene, and to a process for producing such a cap or closure.

A polyethylene composition for producing blow-molded hollow articles, having the following features: 1) a density from 0.945 to 0.958 g/cm.sup.3, determined according to ISO 1183 at 23° C.; 2) a ratio MIF/MI10 from 2 to 10; 3) a η.sub.0.02 from 200,000 to 800,000 Pa.Math.s; 4) a LCBI equal to or lower than 0.80; and 5) a ratio (η.sub.0.02/1000)/LCBI equal to or greater than 350.

A polyethylene composition for producing blow-molded hollow articles, having the following features: 1) a density from 0.945 to 0.958 g/cm.sup.3, determined according to ISO 1183 at 23° C.; 2) a ratio MIF/MI10 from 2 to 10; 3) a η.sub.0.02 from 200,000 to 800,000 Pa.Math.s; 4) a LCBI equal to or lower than 0.80; and 5) a ratio (η.sub.0.02/1000)/LCBI equal to or greater than 350.

A process for the preparation of polyolefins by polymerizing olefins at temperatures of from 20 to 200° C. and pressures of from 0.1 to 20 MPa in the presence of a polymerization catalyst and an antistatically acting composition in a polymerization reactor, wherein the antistatically acting composition is a mixture comprising an oil-soluble surfactant and water and the use of an antistatically acting composition comprising an oil-soluble surfactant and water as antistatic agent for the polymerization of olefins at temperatures of from 20 to 200° C. and pressures of from 0.1 to 20 MPa in the presence of a polymerization catalyst.

A process for the preparation of polyolefins by polymerizing olefins at temperatures of from 20 to 200° C. and pressures of from 0.1 to 20 MPa in the presence of a polymerization catalyst and an antistatically acting composition in a polymerization reactor, wherein the antistatically acting composition is a mixture comprising an oil-soluble surfactant and water and the use of an antistatically acting composition comprising an oil-soluble surfactant and water as antistatic agent for the polymerization of olefins at temperatures of from 20 to 200° C. and pressures of from 0.1 to 20 MPa in the presence of a polymerization catalyst.

The present invention relates to a hybrid supported metallocene catalyst including at least first metallocene compound, at least one second metallocene compound, at least one cocatalyst compound, and a carrier, a preparation method therefor, and a polyolefin resin polymerized in the presence of the catalyst, wherein the second metallocene compound is a compound of a bridged structure having a ligand of an asymmetric structure, and the polyolefin resin has a density of 0.910 g/cm.sup.3 to 0.960 g/cm.sup.3, a molecular weight density in a unimodal distribution of 3 to 5, a melt index of 0.05 to 100 at 2.16 kg, and a melt flow rate of 20 to 40.

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.