A heterophasic polyolefin composition comprising 55 to 95 wt.-% based on the total weight of the heterophasic polyolefin composition of a propylene butene random copolymer (A) having an MFR.sub.2 (230° C.) of 0.3 to 100.0 g/10 min and a butene content of 1.5 to 8.0 wt.-%, wherein the propylene butene random copolymer is obtained by a process using a single site catalyst (I) and 5 to 45 wt.-% based on the total weight of the heterophasic polyolefin composition of a copolymer of ethylene (B) having a density in the range of 910 to 935 kg/m.sup.3 and an MFR.sub.2 (190° C.) of 0.5 to 10 g/10 min, wherein the copolymer of ethylene (B) is obtained by a process using a single site catalyst (II).

A heterophasic polyolefin composition comprising 55 to 95 wt.-% based on the total weight of the heterophasic polyolefin composition of a propylene butene random copolymer (A) having an MFR.sub.2 (230° C.) of 0.3 to 100.0 g/10 min and a butene content of 1.5 to 8.0 wt.-%, wherein the propylene butene random copolymer is obtained by a process using a single site catalyst (I) and 5 to 45 wt.-% based on the total weight of the heterophasic polyolefin composition of a copolymer of ethylene (B) having a density in the range of 910 to 935 kg/m.sup.3 and an MFR.sub.2 (190° C.) of 0.5 to 10 g/10 min, wherein the copolymer of ethylene (B) is obtained by a process using a single site catalyst (II).

The present invention relates to a catalyst system for the production of polyethylene comprising: I) the reaction product obtained by reacting a) a hydrocarbon solution comprising: i. a magnesium-containing compound selected from an organic oxygen-containing magnesium compound and/or a halogen-containing magnesium compound; and ii. an organic oxygen-containing titanium compound wherein the molar ratio of magnesium:titanium is lower than 3:1; and b) an organo aluminium halide having the formula AlR.sub.nX.sub.3-n in which R is a hydrocarbon moiety containing 1-10 carbon atoms, X is a halogen and 0<n<3; II) an aluminium compound having the formula AlR.sub.3, in which R is a hydrocarbon moiety containing 1-10 carbon atoms; and III) one or more of an electron donor selected from the group of 1,2-dialkoxy hydrocarbon compounds wherein the molar ratio of supplied organo aluminium halide I)b) to supplied titanium in I)a) in the preparation of I) is between 5.0 and 7.0; and the molar ratio of the electron donor III) to the titanium present in the reaction product I) is between 0.05 and 0.40 The production of polyethylene using said catalyst system results in a reduction of formation of ethane and a reduction of the hexane-extractable content of the polyethylene.

The present invention relates to a catalyst system for the production of polyethylene comprising: I) the reaction product obtained by reacting a) a hydrocarbon solution comprising: i. a magnesium-containing compound selected from an organic oxygen-containing magnesium compound and/or a halogen-containing magnesium compound; and ii. an organic oxygen-containing titanium compound wherein the molar ratio of magnesium: titanium is lower than 3:1; and b) an organo aluminium halide having the formula AlR.sub.nX.sub.3-n in which R is a hydrocarbon moiety containing 1-10 carbon atoms, X is a halogen and 0<n<3; II) an aluminium compound having the formula AlR.sub.3, in which R is a hydrocarbon moiety containing 1-10 carbon atoms; and III) one or more of an electron donor selected from the group of 1,2-dialkoxy hydrocarbon compounds wherein the molar ratio of supplied organo aluminium halide I)b) to supplied titanium in I) a) in the preparation of I) is between 5.0 and 7.0; and the molar ratio of the electron donor III) to the titanium present in the reaction product I) is between 0.05 and 0.40 The production of polyethylene using said catalyst system results in a reduction of formation of ethane and a reduction of the hexane-extractable content of the polyethylene.

Provided are a method for preparing a catalyst composition for preparing a catalyst composition having improved catalyst activity by pre-treating a hydrogen-bonded lanthanide rare earth element compound and/or an oligomer type of a lanthanide rare earth element compound of Formula 1, which induce the deterioration of the catalyst activity, and a method for preparing a conjugated diene-based polymer using the catalyst composition prepared thereby,

##STR00001## wherein all the variables are described herein.

Provided are a method for preparing a catalyst composition for preparing a catalyst composition having improved catalyst activity by pre-treating a hydrogen-bonded lanthanide rare earth element compound and/or an oligomer type of a lanthanide rare earth element compound of Formula 1, which induce the deterioration of the catalyst activity, and a method for preparing a conjugated diene-based polymer using the catalyst composition prepared thereby,

##STR00001## wherein all the variables are described herein.

A heterophasic polyolefin composition comprising 55 to 95 wt.-% based on the total weight of the heterophasic polyolefin composition of a propylene butene random copolymer (A) having an MFR.sub.2 (230 C.) of 0.3 to 100.0 g/10 min and a butene content of 1.5 to 8.0 wt.-%, wherein the propylene butene random copolymer is obtained by a process using a single site catalyst (I) and 5 to 45 wt.-% based on the total weight of the heterophasic polyolefin composition of a copolymer of ethylene (B) having a density in the range of 910 to 935 kg/m.sup.3 and an MFR.sub.2 (190 C.) of 0.5 to 10 g/10 min, wherein the copolymer of ethylene (B) is obtained by a process using a single site catalyst (II).

A heterophasic polyolefin composition comprising 55 to 95 wt.-% based on the total weight of the heterophasic polyolefin composition of a propylene butene random copolymer (A) having an MFR.sub.2 (230 C.) of 0.3 to 100.0 g/10 min and a butene content of 1.5 to 8.0 wt.-%, wherein the propylene butene random copolymer is obtained by a process using a single site catalyst (I) and 5 to 45 wt.-% based on the total weight of the heterophasic polyolefin composition of a copolymer of ethylene (B) having a density in the range of 910 to 935 kg/m.sup.3 and an MFR.sub.2 (190 C.) of 0.5 to 10 g/10 min, wherein the copolymer of ethylene (B) is obtained by a process using a single site catalyst (II).