A method is disclosed for producing a catalyst, which suppresses a decrease in polymerization activity due to early deactivation of the active site after the catalyst has been formed, exhibits excellent catalyst activity at the time of polymerization of olefins, and can produce polymers of olefins, which are excellent in stereoregularity. The method for producing a catalyst includes contacting a solid catalyst component (A) containing magnesium, titanium, halogen and an internal electron-donating compound, and a specific organoaluminum compound (B) represented by the general formula (I), with each other, wherein at least one selected from the solid catalyst component (A) and the organoaluminum compound (B) is previously subjected to contact treatment with a hydrocarbon compound having one or more vinyl groups, in an organic solvent containing 30% by mass or more of one or more compounds selected from saturated aliphatic hydrocarbon compounds having 20 or more carbon atoms.

The present invention provides a method for producing a catalyst for polymerization of an olefin, which suppresses a decrease in polymerization activity due to early deactivation of the active site after the catalyst has been formed, exhibits excellent catalyst activity at the time of polymerization of olefins, and can produce polymers of olefins, which are excellent in stereoregularity. The method for producing a catalyst for polymerization of an olefin includes contacting a solid catalyst component (A) containing magnesium, titanium, halogen and an internal electron-donating compound, and a specific organoaluminum compound (B) represented by the general formula (I), with each other, wherein at least one selected from the solid catalyst component (A) and the organoaluminum compound (B) is previously subjected to contact treatment with a hydrocarbon compound having one or more vinyl groups.

The present invention provides a method for producing a catalyst for polymerization of an olefin, which suppresses a decrease in polymerization activity due to early deactivation of the active site after the catalyst has been formed, exhibits excellent catalyst activity at the time of polymerization of olefins, and can produce polymers of olefins, which are excellent in stereoregularity. The method for producing a catalyst for polymerization of an olefin includes contacting a solid catalyst component (A) containing magnesium, titanium, halogen and an internal electron-donating compound, and a specific organoaluminum compound (B) represented by the general formula (I), with each other, wherein at least one selected from the solid catalyst component (A) and the organoaluminum compound (B) is previously subjected to contact treatment with a hydrocarbon compound having one or more vinyl groups.

A polypropylene comprising within a range from 0.1 wt % to 4 wt % ethylene and/or C4 to C12 α-olefin derived units, one or more clarifiers, or both; wherein the polypropylene has a flexural modulus of at least 200 kpsi (0.05 in/min ASTM D790(A)) and an Mz/Mw of at least 4. The polypropylenes may be made by combining propylene and a comonomer with a Ziegler-Natta catalyst and at least two external electron donors, wherein the concentration of the electron donors is within a range from 1 to 100 ppm. The concentration of electron donors may be decreased to control the haze level of the polypropylene, and/or the level of comonomer derived units may be controlled to reduce the haze level of the polypropylene.

A polypropylene comprising within a range from 0.1 wt % to 4 wt % ethylene and/or C4 to C12 α-olefin derived units, one or more clarifiers, or both; wherein the polypropylene has a flexural modulus of at least 200 kpsi (0.05 in/min ASTM D790(A)) and an Mz/Mw of at least 4. The polypropylenes may be made by combining propylene and a comonomer with a Ziegler-Natta catalyst and at least two external electron donors, wherein the concentration of the electron donors is within a range from 1 to 100 ppm. The concentration of electron donors may be decreased to control the haze level of the polypropylene, and/or the level of comonomer derived units may be controlled to reduce the haze level of the polypropylene.

The invention relates to a process for the preparation of a propylene homopolymer or a propylene α-olefin random copolymer comprising the step of a) preparing a propylene homopolymer or a propylene α-olefin random copolymer, wherein the α-olefin is chosen from the group consisting of ethylene, and α-olefins having 4 to 10 carbon atoms, for example 1-butene or 1-hexene by contacting at least the propylene and optionally α-olefin, with a catalyst in a gas-phase reactor at a temperature T1 and a pressure P1, wherein T1 is chosen in the range from 75 to 90° C., for example in the range from 77 to 85° C., for example in the range from 78 to 83° C., wherein P1 is chosen in the range from 22 to 30 bar to prepare a propylene homopolymer (A′) or a propylene α-olefin random copolymer (A′).

The invention relates to a process for the preparation of a propylene homopolymer or a propylene α-olefin random copolymer comprising the step of a) preparing a propylene homopolymer or a propylene α-olefin random copolymer, wherein the α-olefin is chosen from the group consisting of ethylene, and α-olefins having 4 to 10 carbon atoms, for example 1-butene or 1-hexene by contacting at least the propylene and optionally α-olefin, with a catalyst in a gas-phase reactor at a temperature T1 and a pressure P1, wherein T1 is chosen in the range from 75 to 90° C., for example in the range from 77 to 85° C., for example in the range from 78 to 83° C., wherein P1 is chosen in the range from 22 to 30 bar to prepare a propylene homopolymer (A′) or a propylene α-olefin random copolymer (A′).

A process for propylene preliminary polymerization in liquid phase that occurs in a continuous preliminary polymerization reactor may include feeding a propylene monomer and a Ziegler-Natta catalyst system having (a) a pro-catalyst having an internal electron donor comprising a substituted phenylene aromatic diester, (b) a catalyst activator and optionally (c) an external donor, into the continuous preliminary polymerization reactor, wherein the feeding is carried out without pre-contact of the pro-catalyst with the catalyst activator, and also without pre-contact of the catalyst activator with the propylene monomer before entering the continuous preliminary polymerization reactor.

A process for propylene preliminary polymerization in liquid phase that occurs in a continuous preliminary polymerization reactor may include feeding a propylene monomer and a Ziegler-Natta catalyst system having (a) a pro-catalyst having an internal electron donor comprising a substituted phenylene aromatic diester, (b) a catalyst activator and optionally (c) an external donor, into the continuous preliminary polymerization reactor, wherein the feeding is carried out without pre-contact of the pro-catalyst with the catalyst activator, and also without pre-contact of the catalyst activator with the propylene monomer before entering the continuous preliminary polymerization reactor.

The purpose of the present invention is to provide a propylene-based block copolymer, the deposition thereof on the inner wall of the polymerization vessel having been sufficiently inhibited. The propylene-based block copolymer of the present invention has a flowability evaluation value of 40% or less, the value being calculated with the following equation wherein X (sec) is the number of seconds over which 100 g of the copolymer having ordinary temperature falls from a stainless-steel funnel having an inner diameter of 11.9 mm and Y (sec) is the number of seconds over which 100 g of the copolymer which has been held at 80° C. for 24 hours under a load of 10 kg falls from the funnel having an inner diameter of 11.9 mm.
Flowability evaluation value (%)={(Y/X)−1}×100.