The present invention describes a process for preparing catalyst for the polymerization of ethylene consisting essentially of the steps of (i) contacting a magnesium based precursor with a solvent; and (ii) then contacting the magnesium based precursor in the solvent with a transition metal compound to obtain the catalyst, wherein step (ii) is single contact step. The present invention also relates to a process for preparation of a catalyst system and a process of polymerizing and/or copolymerizing of ethylene to obtain a polyethylene using the catalyst.

The present invention describes a process for preparing catalyst for the polymerization of ethylene consisting essentially of the steps of (i) contacting a magnesium based precursor with a solvent; and (ii) then contacting the magnesium based precursor in the solvent with a transition metal compound to obtain the catalyst, wherein step (ii) is single contact step. The present invention also relates to a process for preparation of a catalyst system and a process of polymerizing and/or copolymerizing of ethylene to obtain a polyethylene using the catalyst.

A process for producing a cap or closure comprising obtaining a polypropylene composition by sequential polymerization comprising the steps: A) polymerizing in a first reactor, preferably a slurry reactor, in the presence of a Ziegler-Natta catalyst monomers comprising propylene and optionally one or more comonomers selected from ethylene and C4-C10 alpha-olefins, to obtain a first propylene polymer fraction having a comonomer content in the range of 0.0 to 1.8 wt %, and a MFR2 in the range of from 12.0 to 40.0 g/10 min, as measured according to ISO 1133 at 230° C. under a load of 2.16 kg; B) polymerizing in a second reactor, preferably a first gas-phase reactor, monomers comprising propylene and one or more comonomers selected from ethylene and C4-C10 alpha-olefins, in the presence of the first propylene polymer fraction, to obtain a second propylene polymer fraction, wherein the polypropylene composition comprising said first and second propylene polymer fractions has an MFR2 in the range of from 12.0 to 60.0 g/10 min, as measured according to ISO 1133 at 230° C. under a load of 2.16 kg, has a comonomer content in the range of from 2.2 to 5.0 wt % and wherein the ratio of the comonomer content of component A) to the comonomer content of the polypropylene composition is 0.35 or less, C) melting, extruding and moulding the polypropylene composition in the presence of at least one nucleating agent to prepare a cap or closure; and D) exposing the cap or closure obtained in step (C) to a cooling rate of 50 K/s or more.

A process for producing a cap or closure comprising obtaining a polypropylene composition by sequential polymerization comprising the steps: A) polymerizing in a first reactor, preferably a slurry reactor, in the presence of a Ziegler-Natta catalyst monomers comprising propylene and optionally one or more comonomers selected from ethylene and C4-C10 alpha-olefins, to obtain a first propylene polymer fraction having a comonomer content in the range of 0.0 to 1.8 wt %, and a MFR2 in the range of from 12.0 to 40.0 g/10 min, as measured according to ISO 1133 at 230° C. under a load of 2.16 kg; B) polymerizing in a second reactor, preferably a first gas-phase reactor, monomers comprising propylene and one or more comonomers selected from ethylene and C4-C10 alpha-olefins, in the presence of the first propylene polymer fraction, to obtain a second propylene polymer fraction, wherein the polypropylene composition comprising said first and second propylene polymer fractions has an MFR2 in the range of from 12.0 to 60.0 g/10 min, as measured according to ISO 1133 at 230° C. under a load of 2.16 kg, has a comonomer content in the range of from 2.2 to 5.0 wt % and wherein the ratio of the comonomer content of component A) to the comonomer content of the polypropylene composition is 0.35 or less, C) melting, extruding and moulding the polypropylene composition in the presence of at least one nucleating agent to prepare a cap or closure; and D) exposing the cap or closure obtained in step (C) to a cooling rate of 50 K/s or more.

The magnesium alkoxide particle contains the reaction product of the following components: 1) a magnesium powder; 2) a mixed alcohol; 3) a halogenating agent; and 4) a titanate compound. The magnesium alkoxide particle is used for preparing a catalyst for olefin polymerization.

The magnesium alkoxide particle contains the reaction product of the following components: 1) a magnesium powder; 2) a mixed alcohol; 3) a halogenating agent; and 4) a titanate compound. The magnesium alkoxide particle is used for preparing a catalyst for olefin polymerization.

The present invention is directed to articles comprising a heterophasic polypropylene composition. The articles exhibit a combination of high stiffness, good dimensional stability, low shrinkage and reduced warpage properties and fast cycle times. Such articles are suitable in the rigid packaging area. The articles comprise a polypropylene composition comprising a heterophasic propylene copolymer which comprises a) a matrix phase (A) comprising at least one propylene homopolymer and/or a propylene copolymer, and b) a disperse phase (B) comprising a propylene copolymer rubber dispersed in the matrix phase (A), wherein the propylene copolymer rubber of the disperse phase (B) has a comonomer content of 30 to 55 wt. %, wherein the weight ratio of the matrix phase (A) and the disperse phase (B) is from 20:80 to 80:20; and the polypropylene composition has (i) a melt flow rate MFR.sub.2 of 1 g/10 min to 500 g/10 min, determined according to ISO 1133 (230° C., 2.16 kg load); and the article has (ii) a half-time of crystallisation t.sub.1/2 of 1 to 25 msec, measured at 80° C. by fast scanning calorimeter. The invention further relates to a process for preparing such a heterophasic polypropylene composition and its use for e.g. molded articles, in particular injection molded articles such as thin-walled containers.

The present invention is directed to articles comprising a heterophasic polypropylene composition. The articles exhibit a combination of high stiffness, good dimensional stability, low shrinkage and reduced warpage properties and fast cycle times. Such articles are suitable in the rigid packaging area. The articles comprise a polypropylene composition comprising a heterophasic propylene copolymer which comprises a) a matrix phase (A) comprising at least one propylene homopolymer and/or a propylene copolymer, and b) a disperse phase (B) comprising a propylene copolymer rubber dispersed in the matrix phase (A), wherein the propylene copolymer rubber of the disperse phase (B) has a comonomer content of 30 to 55 wt. %, wherein the weight ratio of the matrix phase (A) and the disperse phase (B) is from 20:80 to 80:20; and the polypropylene composition has (i) a melt flow rate MFR.sub.2 of 1 g/10 min to 500 g/10 min, determined according to ISO 1133 (230° C., 2.16 kg load); and the article has (ii) a half-time of crystallisation t.sub.1/2 of 1 to 25 msec, measured at 80° C. by fast scanning calorimeter. The invention further relates to a process for preparing such a heterophasic polypropylene composition and its use for e.g. molded articles, in particular injection molded articles such as thin-walled containers.

A Ziegler-Natta catalyst composition is disclosed. The catalyst composition is formed from a procatalyst containing a magnesium moiety and a titanium moiety. At least one internal electron donor is incorporated into the procatalyst. During a titanation procedure in conjunction with the internal electron donor, a titanium extractant is used to remove or deactivate low activity or atactic titanium active sites.

A Ziegler-Natta catalyst composition is disclosed. The catalyst composition is formed from a procatalyst containing a magnesium moiety and a titanium moiety. At least one internal electron donor is incorporated into the procatalyst. During a titanation procedure in conjunction with the internal electron donor, a titanium extractant is used to remove or deactivate low activity or atactic titanium active sites.