JP2019172945A - METHOD FOR PRODUCING PROPYLENE/α-OLEFIN COPOLYMER - Google Patents

Abstract

To provide a method for producing a propylene copolymer with a high molecular weight without depending on improvement of transition metal compounds used for polymerization catalysts.SOLUTION: A method for producing a propylene/α-olefin copolymer has a polymerization step of polymerizing propylene and α-olefin (excluding propylene) in the presence of a catalyst for olefin polymerization containing a predetermined transition metal compound (A), and a carrier (B) comprising a predetermined solid polyaluminoxane composition carrying the transition metal compound (A).SELECTED DRAWING: None

Description

  The present invention relates to a method for producing a propylene / α-olefin copolymer.

  Propylene-based copolymers are used in various applications as thermoplastic resins or as modifiers for thermoplastic resins. As a polymerization catalyst used when producing a propylene-based copolymer, a titanium-based catalyst, a metallocene-based catalyst, and the like are known. However, when propylene is copolymerized using a titanium-based catalyst, the composition of the propylene copolymer that can be produced is limited, or the propylene copolymer has a broad molecular weight distribution and is not easily compatible with other resins. There was a problem. On the other hand, when propylene is copolymerized using a metallocene-based catalyst, it has the advantage of being excellent in copolymerization with α-olefins and capable of being polymerized in a wide range of compositions. On the other hand, when the polymerization temperature is increased, the molecular weight is increased. There was a problem that it was difficult to extend or it was difficult to realize low cost because of low polymerization activity.

  In order to solve the problems in the case where a metallocene catalyst is used and to produce a high molecular weight propylene copolymer, the transition metal compound (metallocene compound) constituting the metallocene catalyst has been actively improved. Yes. For example, in Patent Documents 1 to 3, propylene and other α-olefins in the presence of a catalyst containing a transition metal compound having a ligand in which a cyclopentadienyl ring and a fluorenyl ring are bridged are disclosed. Copolymerization is described.

  On the other hand, Patent Document 4 discloses a solid polyaluminoxane composition having a predetermined characteristic, which is useful as a promoter and a catalyst carrier for a catalyst for producing an olefin polymer.

JP 2004-161957 A International Publication No. 2006/025540 JP 2007-302853 A International Publication No. 2014/123212

  As described above, in order to produce a propylene-based copolymer having a high molecular weight, the transition metal compound used for the polymerization catalyst has been conventionally improved. However, the improvement of the transition metal compound cannot be easily achieved. For this reason, if the technique of raising the molecular weight of a propylene-type copolymer is developed without improving a transition metal compound, the utility value will be high.

  Accordingly, an object of the present invention is to provide a method for producing a propylene-based copolymer having a high molecular weight without depending on improvement of a transition metal compound used for a polymerization catalyst.

  The present inventors have intensively studied to solve the above problems. As a result, it has been found that the above-mentioned problems can be solved by using a specific transition metal compound as the transition metal compound and a solid polyaluminoxane composition as the carrier, and the present invention has been completed.

The gist of the present invention is as follows.
[1]
Production of propylene / α-olefin copolymer having a polymerization step of polymerizing propylene and α-olefin (excluding propylene) in the presence of a catalyst for olefin polymerization including transition metal compound (A) and carrier (B). A method,
The transition metal compound (A) is represented by the following general formula [I]:

[In the formula [I], R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ and R ¹⁴ are each Independently a hydrogen atom, a hydrocarbon group, a heteroatom-containing hydrocarbon group or a silicon-containing group, and any two substituents of R ¹ to R ⁴ are bonded to each other to form a ring. Of the substituents R ⁵ to R ¹² , any two substituents may be bonded to each other to form a ring, and R ¹³ and R ¹⁴ are bonded to each other to form a ring. You may,
Y is a carbon atom, a silicon atom or a germanium atom;
M is a Group 4 transition metal atom,
j is an integer of 1 to 4,
Q is a halogen atom, a hydrocarbon group, an anionic ligand, or a neutral ligand that can be coordinated by a lone electron pair. When j is an integer of 2 or more, Q is selected in the same or different combination. ]
The carrier (B) comprises a solid polyaluminoxane composition containing a structural unit represented by the following formula [II] and having an aluminum content of 36% by mass or more,

The method for producing a propylene / α-olefin copolymer in which the transition metal compound (A) is supported on the carrier (B).
[2]
In the general formula [I], R ¹ , R ³ , R ¹³ and R ¹⁴ are each independently a hydrocarbon group having 1 to 10 carbon atoms, and R ⁶ , R ⁷ , R ¹⁰ and R ¹¹ are each independently The hydrogen atom or hydrocarbon group, R ² , R ⁴ , R ⁵ , R ⁸ , R ⁹ and R ¹² are hydrogen atoms, Y is a carbon atom, and M is a zirconium atom; A method for producing a propylene / α-olefin copolymer.

[3]
In the general formula [I], R ³ is a hydrocarbon group containing a quaternary carbon, and R ¹³ and R ¹⁴ are each independently an aryl group, and the propylene / α-olefin copolymer of the above [1] or [2] A method for producing a polymer.

[4]
The method for producing a propylene / α-olefin copolymer according to any one of [1] to [3], wherein the α-olefin is ethylene.

[5]
The method for producing a propylene / α-olefin copolymer according to any one of [1] to [4], wherein the polymerization method in the polymerization step is bulk polymerization using propylene as a solvent.

[6]
The propylene / α-olefin copolymer of any one of [1] to [5], wherein the solid polyaluminoxane composition is in the form of particles and the volume-based median diameter (D50) is in the range of 0.1 to 100 μm. Manufacturing method of coalescence.

[7]
The method for producing a propylene / α-olefin copolymer according to any one of [1] to [6], wherein the solid polyaluminoxane composition satisfies the following requirements (i) and (ii).
Requirement (i): The solubility in n-hexane at 25 ° C. measured by the following method (i) is less than 2.0 mol%.
Requirement (ii): The solubility in toluene at 25 ° C. measured by the following method (ii) is less than 2.0 mol%.

[Method (i)]
2 g of the solid polyaluminoxane composition is added to 50 mL of n-hexane maintained at 25 ° C., followed by stirring for 2 hours, followed by separation into a filtrate and a residue by filtration, and the aluminum in the filtrate. The concentration is measured using ICP emission spectroscopy (ICP-AES), and the solubility is determined as the ratio of aluminum atoms present in the filtrate to the amount of aluminum atoms corresponding to 2 g of the solid polyaluminoxane composition.

[Method (ii)]
Solubility is calculated | required by the method similar to the said method (i) except using toluene instead of n-hexane.

[8]
The propylene / α-olefin according to any one of [1] to [7], wherein the solid polyaluminoxane composition is in the form of particles and a uniformity index represented by the following formula of the composition is 0.45 or less. A method for producing a copolymer.

Uniformity index = ΣXi | D50−Di | / D50ΣXi
[Wherein, Xi represents a histogram value of particle i in particle size distribution measurement, D50 represents a volume-based median diameter, and Di represents a volume-based diameter of particle i. ]

  According to the production method of the present invention, it is possible to produce a propylene copolymer having a high molecular weight without depending on the improvement of the transition metal compound used for the metallocene catalyst.

Hereinafter, the method for producing a propylene-based copolymer according to the present invention will be described in more detail.
[Olefin polymerization catalyst]
The olefin polymerization catalyst used in the present invention contains a transition metal compound (A) and a carrier (B) described below.

<Transition metal compound (A)>
The transition metal compound (A) used in the present invention is represented by the following general formula [I].

In the formula [I], R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ and R ¹⁴ are each independent. Are a hydrogen atom, a hydrocarbon group, a heteroatom-containing hydrocarbon group or a silicon-containing group, and any two substituents of R ¹ to R ⁴ are bonded to each other to form a ring. Of the substituents R ⁵ to R ¹² , any two substituents may be bonded to each other to form a ring, and R ¹³ and R ¹⁴ are bonded to each other to form a ring. You may,
Y is a carbon atom, a silicon atom or a germanium atom;
M is a Group 4 transition metal atom,
j is an integer of 1 to 4,
Q is a halogen atom, a hydrocarbon group, an anionic ligand, or a neutral ligand that can be coordinated by a lone electron pair. When j is an integer of 2 or more, Q is selected in the same or different combination.

<R ¹⁴ from R ^1>
Examples of the hydrocarbon group in R ¹ to R ¹⁴ include one or more of a linear hydrocarbon group, a branched hydrocarbon group, a cyclic saturated hydrocarbon group, a cyclic unsaturated hydrocarbon group, and a saturated hydrocarbon group. And a group formed by substituting a hydrogen atom of a cyclic unsaturated hydrocarbon group. Carbon number of a hydrocarbon group is 1-20 normally, Preferably it is 1-15, More preferably, it is 1-10.

  Examples of the linear hydrocarbon group include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, and n-nonyl. And linear alkyl groups such as n-decanyl group; linear alkenyl groups such as allyl group.

  Examples of the branched hydrocarbon group include isopropyl group, tert-butyl group, tert-amyl group, 3-methylpentyl group, 1,1-diethylpropyl group, 1,1-dimethylbutyl group, 1-methyl-1 Examples thereof include branched alkyl groups such as -propylbutyl group, 1,1-propylbutyl group, 1,1-dimethyl-2-methylpropyl group, and 1-methyl-1-isopropyl-2-methylpropyl group.

  Examples of the cyclic saturated hydrocarbon group include cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, and methylcyclohexyl group; and polycyclic groups such as norbornyl group, adamantyl group, and methyladamantyl group. It is done.

  Examples of the cyclic unsaturated hydrocarbon group include an aryl group such as a phenyl group, a tolyl group, a naphthyl group, a biphenyl group, a phenanthryl group, and an anthracenyl group; a cycloalkenyl group such as a cyclohexenyl group; and 5-bicyclo [2.2. 1] Polycyclic unsaturated alicyclic groups such as a hepta-2-enyl group.

  Examples of the group formed by substituting one or more hydrogen atoms of a saturated hydrocarbon group with a cyclic unsaturated hydrocarbon group include a benzyl group, a cumyl group, a 1,1-diphenylethyl group, and a triphenylmethyl group. And a group formed by substituting one or two or more hydrogen atoms of the alkyl group with an aryl group.

Examples of the hetero atom-containing hydrocarbon group in R ¹ to R ¹⁴ include, for example, an alkoxy group such as a methoxy group and an ethoxy group, an aryloxy group such as a phenoxy group, and an oxygen atom-containing hydrocarbon group such as a furyl group; N-methylamino A nitrogen atom-containing hydrocarbon group such as a group, an amino group such as an N, N-dimethylamino group and an N-phenylamino group, and a pyryl group; and a sulfur atom-containing hydrocarbon group such as a thienyl group. Carbon number of a hetero atom containing hydrocarbon group is 1-20 normally, Preferably it is 2-18, More preferably, it is 2-15. However, the silicon-containing group is excluded from the heteroatom-containing hydrocarbon group.

Examples of the silicon-containing group in R ¹ to R ¹⁴ include a formula —SiR ₃ such as trimethylsilyl group, triethylsilyl group, dimethylphenylsilyl group, diphenylmethylsilyl group, triphenylsilyl group, etc. Independently an alkyl group having 1 to 15 carbon atoms or a phenyl group).

Of the substituents from R ¹ to R ¹⁴ , any two substituents such as two adjacent substituents (eg, R ¹ and R ² , R ² and R ³ , R ³ and R ⁴ , R ⁵ and R ⁶ , R ⁶ and R ⁷ , R ⁷ and R ⁸ , R ⁹ and R ¹⁰ , R ¹⁰ and R ¹¹ , R ¹¹ and R ¹² , R ¹³ and R ¹⁴ ) are bonded to each other to form a ring. Also good. Two or more ring formations may exist in the molecule.

  In this specification, examples of the ring (additional ring) formed by bonding two substituents to each other include an alicyclic ring, an aromatic ring, and a heterocyclic ring. Specific examples include a cyclohexane ring; a benzene ring; a hydrogenated benzene ring; a cyclopentene ring; a hetero ring such as a furan ring and a thiophene ring and a corresponding hydrogenated hetero ring, preferably a cyclohexane ring; a benzene ring and a hydrogen Benzene ring. Such a ring structure may further have a substituent such as an alkyl group on the ring.

In the general formula [I], R ⁵ , R ⁸ , R ⁹ and R ¹² are preferably hydrogen atoms.
R ⁶ , R ⁷ , R ¹⁰ and R ¹¹ are preferably a hydrogen atom, a hydrocarbon group, an oxygen atom-containing hydrocarbon group or a nitrogen atom-containing hydrocarbon group, more preferably a hydrocarbon group, particularly preferably It is a C1-C10 hydrocarbon group.

R ⁶ and R ⁷ may be bonded to each other to form a ring, and R ¹⁰ and R ¹¹ may be bonded to each other to form a ring. As a structure of the fluorenyl group part which has such a ring, what is represented by the following Formula is mentioned, for example.

R ¹³ and R ¹⁴ are preferably a hydrocarbon group having 1 to 10 carbon atoms, a heteroatom-containing hydrocarbon group or a silicon-containing group, and more preferably an aryl group or substituted aryl group having 6 to 10 carbon atoms (heteroatom A hydrocarbon group or an aryl group having a silicon-containing group), particularly preferably an aryl group of a hydrocarbon group having 6 to 10 carbon atoms, and most preferably a phenyl group.

<Y>
Y is preferably a carbon atom.
<M, Q, j>
M is a Group 4 transition metal, preferably Ti, Zr or Hf, more preferably Zr or Hf, and particularly preferably Zr.

Examples of the halogen atom for Q include fluorine, chlorine, bromine, and iodine.
Examples of the hydrocarbon group for Q include the same groups as the hydrocarbon groups for R ¹ to R ^14, and alkyl groups such as a linear alkyl group and a branched alkyl group are preferable.

  Examples of the anionic ligand for Q include alkoxy groups such as methoxy and tert-butoxy; aryloxy groups such as phenoxy; carboxylate groups such as acetate and benzoate; sulfonate groups such as mesylate and tosylate; dimethylamide and diisopropylamide Amide groups such as methylanilide and diphenylamide.

  Examples of the neutral ligand capable of coordinating with a lone pair in Q include, for example, organophosphorus compounds such as trimethylphosphine, triethylphosphine, triphenylphosphine, diphenylmethylphosphine; tetrahydrofuran, diethyl ether, dioxane, 1,2- Examples include ethers such as dimethoxyethane.

It is preferable that at least one Q is a halogen atom or an alkyl group.
j is preferably 2.
The preferred embodiments of the configuration of the transition metal compound (A), that is, R ^{1 to} R ¹⁴ , Y, M, Q, and j have been described above. In the present invention, any combination of the preferred embodiments is also a preferred embodiment.

  Preferred examples of the transition metal compound (A) include compounds listed on pages 62 to 68 of WO 2004/87775, and compounds listed on pages 9 to 37 of WO 2006/25540. And compounds listed in JP-A-2007-302854, [0056] to [0065], more specifically, for example, diphenylmethylene (3-tert-butyl-5-methylcyclopentadienyl) (2,7-di tert-butylfluorenyl) zirconium dichloride, diphenylmethylene (3-tert-butyl-5-ethylcyclopentadienyl) (2,7-ditert-butylfluorenyl) zirconium dichloride, diphenylmethylene (3-tert- Butyl-5-n-propylcyclopentadienyl) (2,7-ditert-butylfluorenyl) zirconium dichloride, diphenylmethylene (3-tert-butyl-5-butylcyclope) Ntadienyl) (2,7-ditert-butylfluorenyl) zirconium dichloride, diphenylmethylene (3-tert-butyl-5-pentylcyclopentadienyl) (2,7-ditert-butylfluorenyl) zirconium dichloride Dimethylmethylene (3-tert-butyl-5-methylcyclopentadienyl) (fluorenyl) zirconium dichloride, (ethyl) (phenyl) methylene (3-tert-butyl-5-methylcyclopentadienyl) (octamethylocta Hydrodibenzofluorenyl) zirconium dichloride, (methyl) (phenyl) methylene (3-tert-butyl-5-methylcyclopentadienyl) (1,1,3,6,8,8, -hexamethyl-1H, 8H -Dicyclopenta [b, h] fluorenyl) zirconium dichloride, and those compounds in which zirconium is replaced with titanium or hafnium. However, the transition metal compound (A) is not limited to the compounds exemplified above.

<Carrier (B)>
The carrier (B) used in the present invention is a carrier that supports the transition metal compound (A) and includes a structural unit represented by the following formula [II] and has an Al content of 36% by mass or more. The composition (hereinafter also referred to as “solid polyaluminoxane composition (B)”).

  The solid polyaluminoxane composition (B) contains, for example, a polyalkylaluminoxane and also contains a trialkylaluminum or a triarylaluminum (hereinafter also referred to as “trialkylaluminum”), preferably a propylene-based copolymer. It contains polyalkylaluminoxane and trimethylaluminum containing the structural unit represented by the formula [II], more preferably polymethylaluminoxane and trimethylaluminum, because the promoter performance for the catalyst for producing the polymer is excellent. Containing.

  The polyalkylaluminoxane contained in the solid polyaluminoxane composition (B) has the following general formula [III]:

[Wherein, R usually represents a hydrocarbon group having 2 to 20 carbon atoms, preferably a hydrocarbon group having 2 to 15 carbon atoms, and more preferably a hydrocarbon group having 2 to 10 carbon atoms. Indicates. ] May be included.

  The structure of polyalkylaluminoxane is not necessarily clarified, and usually has a structure in which the unit represented by the formula [II] and optionally the unit represented by the general formula [III] are repeated about 2 to 50 times. Presumed to contain. Further, the unit connection is various, for example, linear, cyclic or cluster, and polyalkylaluminoxane is usually estimated to be one of these or a mixture thereof. ing.

  Specific examples of the hydrocarbon group as R in the formula [III] include ethyl, propyl, n-butyl, pentyl, hexyl, octyl, decyl, isopropyl, isobutyl, sec-butyl, tert-butyl, 2-methylbutyl, 3 -Methylbutyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 2-methylhexyl, 3-methylhexyl, 2-ethylhexyl, cyclohexyl, cyclooctyl, phenyl, tolyl.

  Examples of the trialkylaluminum include trimethylaluminum having a methyl group, trialkylaluminum having a hydrocarbon group having 2 to 20 carbon atoms, and triarylaluminum.

Specific examples of the trialkylaluminum having a hydrocarbon group having 2 to 20 carbon atoms include triethylaluminum, tripropylaluminum, tri (n-butyl) aluminum, tripentylaluminum, trihexylaluminum, trioctylaluminum, tridecyl Tri (n-alkyl) aluminum such as aluminum;
Triisopropylaluminum, triisobutylaluminum, tri (sec-butyl) aluminum, tri (tert-butyl) aluminum, tri (2-methylbutyl) aluminum, tri (3-methylbutyl) aluminum, tri (2-methylpentyl) aluminum, tri Tri-branched alkyl aluminums such as (3-methylpentyl) aluminum, tri (4-methylpentyl) aluminum, tri (2-methylhexyl) aluminum, tri (3-methylhexyl) aluminum, tri (2-ethylhexyl) aluminum;
And tricycloalkylaluminum such as tricyclohexylaluminum and tricyclooctylaluminum.

Examples of triaryl aluminum include triphenyl aluminum and tolyl aluminum.
As the trialkylaluminum, a trialkylaluminum having any alkyl group can be used regardless of the type of polyalkylaluminoxane. Among these, trimethylaluminum is preferably used from the viewpoint of activity as a cocatalyst and raw material procurement.

  Examples of the solid polyaluminoxane composition (B) include solid polyaluminoxane compositions disclosed in International Publication No. 2010/055562 and International Publication No. 2014/123212.

In the method for producing a propylene-based copolymer of the present invention, an aluminum content is not less than 36% by mass, not a carrier composed of SiO ₂ (hereinafter also referred to as “silica carrier”), which has been conventionally used as a carrier. The solid polyaluminoxane composition (B) is used. According to the method for producing a propylene-based copolymer of the present invention using a carrier comprising a transition metal compound (A) and a solid polyaluminoxane composition (B) having an aluminum content of 36% by mass or more, the same transition metal compound ( A propylene-based copolymer having a high molecular weight can be produced as compared with the case where a conventional method for producing a propylene-based copolymer using A) and a silica carrier is used. The reason for this is not necessarily clear, but if a carrier having a high aluminum content is used, the structure of the cation complex species formed from the transition metal compound and aluminum as the promoter component, such as the distance between the promoter and the cation complex, etc. It is conceivable that the insertion reaction of the monomer into the polymer chain is promoted and / or the rate of chain transfer to the monomer is reduced, contributing to the improvement of the molecular weight. This effect is obtained when each of the various transition metal compounds (A) represented by the formula [I] is used. That is, when a polymerization catalyst obtained by supporting a transition metal compound (A) on the carrier (B) is used, a polymerization catalyst obtained by supporting the same transition metal compound (A) on a silica carrier is used. A higher molecular weight propylene copolymer is obtained than in the case.

  The aluminum content of the solid polyaluminoxane composition (B) varies depending on the structure of polyaluminoxane and trialkylaluminum and the ratio of polyaluminoxane and trialkylaluminum in the solid polyaluminoxane composition (B). From the above viewpoint, the aluminum content is 36% by mass or more, preferably 40% by mass or more, more preferably 41% by mass or more, and particularly preferably 42% by mass or more. The upper limit may be 47% by mass, for example.

The solid polyaluminoxane composition (B) preferably satisfies the following requirements (i) and (ii).
Requirement (i): The solubility in n-hexane at 25 ° C. measured by the following method (i) is less than 2.0 mol%, preferably 1.0 mol% or less, more preferably 0.50 mol% or less, Especially preferably, it is 0.30 mol% or less.

  Requirement (ii): The solubility in toluene at 25 ° C. measured by the following method (ii) is less than 2.0 mol%, preferably 1.0 mol% or less, more preferably 0.50 mol% or less, particularly preferably Is 0.30 mol% or less.

[Method (i)]
2 g of a solid polyaluminoxane composition is added to 50 mL of n-hexane maintained at 25 ° C., followed by stirring for 2 hours, followed by separation into a filtrate and a residue by filtration, and the concentration of aluminum in the filtrate Is measured using ICP emission spectroscopy (ICP-AES), and the solubility is determined as the ratio of aluminum atoms present in the filtrate to the amount of aluminum atoms corresponding to 2 g of the solid polyaluminoxane composition.

[Method (ii)]
Solubility is calculated | required by the method similar to the said method (i) except having used toluene instead of n-hexane. Specifically, the solubility is such that 2 g of solid polyaluminoxane composition is added to 50 mL of toluene maintained at 25 ° C., followed by stirring for 2 hours, followed by filtration to separate the filtrate and the residue, The aluminum concentration in the filtrate was measured using ICP emission spectroscopy (ICP-AES), and the ratio of aluminum atoms present in the filtrate to the amount of aluminum atoms corresponding to 2 g of the solid polyaluminoxane composition was measured. Determine solubility.

  The solid polyaluminoxane composition (B) used in the present invention preferably has low solubility in n-hexane and toluene maintained at 25 ° C. In the olefin polymerization reaction step and / or the catalyst preparation step, elution of the cocatalyst component, the main catalyst component, or the reaction composition of the main catalyst component and the cocatalyst component into the reaction solvent produces an amorphous olefin polymer. This contributes to fouling in a polymerization reactor or the like. Therefore, the composition has low solubility in an aliphatic hydrocarbon solvent typified by n-hexane and an aromatic hydrocarbon solvent typified by toluene used in an olefin polymerization reaction step and / or a catalyst preparation step thereof. Moderately good.

The solid polyaluminoxane composition (B) is preferably in the form of particles and has a specific surface area of 400 to 900 m ² / g. It is known that the specific surface area of the carrier greatly affects the catalyst activity in the olefin polymerization reaction. If the specific surface area is small, the activation efficiency of the transition metal complex serving as the main catalyst decreases, and the catalytic activity decreases. There is a fear. On the other hand, if the specific surface area is too high, since the pore diameter of the support is generally small, the transition metal complex as the main catalyst may not be uniformly supported on the support. From the above, the specific surface area is preferably in the range of 400~900m ² / g, and more preferably in the range of 420~800m ² / g. The specific surface area can be determined using the BET adsorption isotherm and utilizing the gas adsorption and desorption phenomena on the solid surface.

  The solid polyaluminoxane composition (B) in the form of particles preferably has a volume-based median diameter (median diameter, D50) in the range of 0.1 to 100 μm. When used as an olefin polymerization (multimerization) catalyst component, if the average particle size is larger than 100 μm, a large amount of coarse polymer particles are produced, which may cause troubles such as blockage of a polymer outlet and a polymer transfer line. On the other hand, when the average particle size is smaller than 0.1 μm, a lot of fine polymer particles are generated, and not only the problem of charging due to static electricity is likely to occur, but also production efficiency is lowered due to deterioration of sedimentation property and filterability. Problems may occur. From the above, the volume-based median diameter (median diameter, D50) is preferably in the range of 0.1 to 100 μm, more preferably in the range of 0.5 to 80 μm, and still more preferably 1.0. It is in the range of ˜60 μm, and particularly preferably in the range of 5.0 to 55 μm. The volume-based median diameter (median diameter, D50) can be obtained by a laser diffraction / scattering method using, for example, MT3300EX II manufactured by Microtrac. The specific method is described in the test examples.

International Publication No. 2010/055562 describes an index representing the uniformity of the particle diameter of a particulate solid polyaluminoxane composition represented by the following formula.
Uniformity index = ΣXi | D50−Di | / D50ΣXi
[Xi is a histogram value of particle i in particle size distribution measurement, D50 is a volume-based median diameter, and Di is a volume-based diameter of particle i. ]
In this index, the larger the value, the wider the distribution.

  In the production method of the present invention, from the viewpoint of stable operation of the polymerization step, the solid polyaluminoxane composition (B) preferably has a narrow particle size distribution, and the uniformity index is preferably 0.45 or less, Preferably it is 0.40 or less, Most preferably, it is 0.27 or less. Considering that the solid polyaluminoxane composition (B) is formed into particles by self-association, the lower limit of the uniformity index may be, for example, 0.15.

  The carrier (B) preferably contains no solid carrier other than the solid polyaluminoxane composition (B). Examples of solid carriers other than the solid polyaluminoxane composition (B) include solid inorganic carriers such as silica, alumina, silica-alumina, and magnesium chloride, and solid organic carriers such as polystyrene beads.

[Olefin polymerization catalyst]
The olefin polymerization catalyst used in the present invention contains the transition metal compound (A) and the carrier (B). The transition metal compound (A) is supported on the carrier (B).

  The olefin polymerization catalyst is further referred to as at least one compound selected from (C) (C-1) an organometallic compound and (C-2) an organoaluminum oxy compound (hereinafter referred to as “compound (C)”). ) Is preferably contained.

Hereinafter, Compound C will be specifically described.
<Compound (C)>
<< Organic metal compound (C-1) >>
Examples of the organometallic compound (C-1) include an organoaluminum compound (C-1a) represented by the general formula (C-1a), a Group 1 metal represented by the general formula (C-1b), and aluminum. A complex alkylated product (C-1b), a dialkyl compound (C-1c) of a group 2 or group 12 metal represented by the general formula (C-1c), Examples include Group 13 organometallic compounds.

_{(C-1a): Ra m} Al (ORb) n H p X q
In formula (C-1a), Ra and Rb are each independently a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms, X is a halogen atom, m is 0 <m ≦ 3, and n is 0 ≦ n <3, p is a number satisfying 0 ≦ p <3, q is a number satisfying 0 ≦ q <3, and m + n + p + q = 3. Examples of the organoaluminum compound (C-1a) include trialkylaluminum such as trimethylaluminum, triethylaluminum, and triisobutylaluminum, dialkylaluminum hydride such as diisobutylaluminum hydride, and tricycloalkylaluminum.

(C-1b): M2AlRa ₄
In formula (C-1b), M2 is Li, Na or K, and Ra is a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms. Examples of the complex alkylated product (C-1b) include LiAl (C ₂ H ₅ ) ₄ and LiAl (C ₇ H ₁₅ ) ₄ .

(C-1c): RaRbM3
In formula (C-1c), Ra and Rb are each independently a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms, and M3 is Mg, Zn or Cd. Examples of the compound (C-1c) include dimethyl magnesium, diethyl magnesium, di n-butyl magnesium, ethyl n-butyl magnesium, diphenyl magnesium, dimethyl zinc, diethyl zinc, di n-butyl zinc, and diphenyl zinc.

Of the organometallic compounds (C-1), organoaluminum compounds (C-1a) are preferred.
An organometallic compound (C-1) may be used individually by 1 type, and may use 2 or more types together.

《Organic aluminum oxy compound (C-2)》
The organoaluminum oxy compound (C-2) may be, for example, a conventionally known aluminoxane, which is insoluble or hardly soluble in benzene as exemplified in JP-A-2-78687. It may be a compound. A conventionally well-known aluminoxane can be manufactured, for example by the method of following (1)-(4), and is normally obtained as a solution of a hydrocarbon solvent.

  (1) A compound containing adsorbed water or a salt containing water of crystallization, such as magnesium chloride hydrate, copper sulfate hydrate, aluminum sulfate hydrate, nickel sulfate hydrate, first cerium chloride hydrate A method of reacting adsorbed water or crystal water with an organoaluminum compound by adding an organoaluminum compound such as trialkylaluminum to a hydrocarbon medium suspension such as

  (2) A method in which water, ice or water vapor is directly applied to an organoaluminum compound such as trialkylaluminum in a medium such as benzene, toluene, diethyl ether or tetrahydrofuran.

  (3) A method in which an organotin oxide such as dimethyltin oxide or dibutyltin oxide is reacted with an organoaluminum compound such as trialkylaluminum in a medium such as decane, benzene, or toluene.

  (4) Non-hydrolytic conversion such as thermal decomposition of compounds produced by reacting organic aluminum such as trialkylaluminum with organic compounds having carbon-oxygen bonds such as alcohols, ketones and carboxylic acids. how to.

  The aluminoxane may contain a small amount of an organometallic component. Alternatively, the solvent or the unreacted organoaluminum compound may be removed by distillation from the recovered aluminoxane solution, and then redissolved in a solvent or suspended in a poor aluminoxane solvent.

  Specific examples of the organoaluminum compound used in preparing the aluminoxane include the same organoaluminum compounds as those exemplified as the organoaluminum compound (C-1a). Among these, trialkylaluminum and tricycloalkylaluminum are preferable, and trimethylaluminum is particularly preferable.

  Other examples of the organoaluminum oxy compound (C-2) include modified methylaluminoxane. Modified methylaluminoxane is an aluminoxane prepared using trimethylaluminum and an alkylaluminum other than trimethylaluminum. Such a compound is generally called MMAO. MMAO can be prepared by the methods listed in US Pat. No. 4,960,878 and US Pat. No. 5,041,584. In addition, aluminoxanes prepared by using trimethylaluminum and triisobutylaluminum from Tosoh Finechem Co., Ltd. and having R as an isobutyl group are commercially produced under the names MMAO and TMAO.

  Such MMAO is an aluminoxane having improved solubility in various solvents and storage stability. Specifically, unlike MMAO, which is insoluble or hardly soluble in benzene, aliphatic hydrocarbons and It has the feature of being soluble in alicyclic hydrocarbons.

  Further, as the organoaluminum oxy compound (C-2), for example, an organoaluminum oxy compound containing a boron atom and halogens exemplified in International Publication Nos. 2005/066191 and 2007/131010 can be used. Examples of the aluminoxane include ionic aluminoxane as exemplified in International Publication No. WO2003 / 082879.

A compound (C-2) may be used individually by 1 type, and may use 2 or more types together.
<Usage and order of addition of each component>
In the case of propylene copolymerization, the usage method and order of addition of each component are arbitrarily selected, and the following methods are exemplified. Hereinafter, the transition metal compound (A), the carrier (B), and the compound (C) are also referred to as “components (A) to (C)”, respectively.
(1) A method in which a catalyst component carrying component (A) on component (B) is added to a polymerization vessel.
(2) a catalyst component carrying component (A) on component (B),
A method of adding the component (C) to the polymerization vessel in an arbitrary order.
(3) A method in which a catalyst component in which component (A) and component (C) are supported on component (B) is added to the polymerization vessel.

In each of the above methods, at least two of the catalyst components may be contacted in advance.
In the method (3) in which the component (C) is supported, the unsupported component (C) may be added in any order as necessary. In this case, the component (C) may be the same or different. In the solid catalyst component in which the component (B) is supported on the component (B) and the solid catalyst component in which the component (A) and the component (C) are supported on the component (B), the olefin is prepolymerized. Alternatively, a catalyst component may be further supported on the prepolymerized solid catalyst component.

  The method of supporting component (A) or component (C) on component (B) is not particularly limited as long as the effects of the present invention are exhibited, but it is preferable to support component (B) in a state dispersed in a solvent. .

  Examples of the solvent include polar solvents, aromatic solvents, and hydrocarbon solvents, and aromatic solvents or hydrocarbon solvents are particularly preferable. Examples of the polar solvent include diethyl ether, tetrahydrofuran, dioxane, cyclopentyl methyl ether and the like. Examples of the aromatic solvent include benzene, toluene, xylene, mesitylene and the like. Examples of the hydrocarbon solvent include pentane, hexane, heptane, octane, nonane, decane, dodecane, cyclopentane, cyclohexane, and methylcyclopentane. Two or more solvents may be mixed and used in an arbitrary ratio.

  Although the temperature at the time of carrying a component (A) and a component (C) to a component (B) is not specifically limited, Usually, it is -50 degreeC-120 degreeC, Preferably it is -20 degreeC-100 degreeC, Most preferably It is 0 degreeC-70 degreeC.

  The ratio of the component (A) based on the mass of the olefin polymerization catalyst [that is, the mass of the component (A) (g) / the mass of the olefin polymerization catalyst (g) × 100 (mass%)] is 0.00. It can be used in an amount of 01 to 50% by mass, preferably 0.01 to 30% by mass, more preferably 0.1 to 20% by mass, and most preferably 0.5 to 10% by mass.

[Propylene-based copolymer production method]
The method for producing a propylene-based copolymer of the present invention includes a step (polymerization step) of polymerizing propylene and α-olefin (excluding propylene) in the presence of the olefin polymerization catalyst. “Polymerization of propylene and α-olefin (excluding propylene) in the presence of an olefin polymerization catalyst” means that olefin polymerization can be performed by any method as in the above methods (1) to (3). In this embodiment, propylene and α-olefin (excluding propylene) are polymerized by adding each component of the catalyst for polymerization to a polymerization vessel.

  Preferably, a propylene copolymer is produced by polymerizing propylene and at least one olefin A selected from ethylene and an α-olefin having 4 to 30 carbon atoms in the presence of the olefin polymerization catalyst. To do.

  In the present invention, the polymerization can be carried out by either a liquid phase polymerization method such as solution polymerization or suspension polymerization or a gas phase polymerization method. Examples of the inert hydrocarbon medium used in the liquid phase polymerization method include aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, dodecane, and kerosene; cyclopentane, cyclohexane, methylcyclopentane, and the like. And alicyclic hydrocarbons; aromatic hydrocarbons such as benzene, toluene and xylene; and halogenated hydrocarbons such as ethylene chloride, chlorobenzene and dichloromethane. An inert hydrocarbon medium may be used individually by 1 type, and 2 or more types may be mixed and used for it. In particular, a so-called bulk polymerization method using a liquefied olefin itself that can be supplied to the polymerization as a solvent is preferable.

When the olefin polymerization is performed using the olefin polymerization catalyst, the amount of each component that can constitute the olefin polymerization catalyst is as follows.
Component (A) is generally used in an amount of 10 ⁻¹⁰ to 10 ⁻² mol, preferably 10 ⁻⁹ to 10 ⁻³ mol, per liter of reaction volume. Component (C-1) has a molar ratio [(C-1) / M] of component (C-1) to all transition metal atoms (M) in component (A) of usually 1 to 50,000, preferably Can be used in an amount of 10 to 20,000, particularly preferably 50 to 10,000. Component (C-2) has a molar ratio [Al / M] of aluminum atoms in component (C-2) to all transition metal atoms (M) in component (A) of usually 10 to 30,000, preferably Can be used in an amount of 20 to 10,000.

  In the production method of the present invention, the polymerization temperature in the polymerization step is usually −50 to + 200 ° C., preferably 0 to 180 ° C .; the polymerization pressure is usually normal pressure to 10 MPa gauge pressure, preferably normal pressure to 5 MPa gauge. Pressure. The polymerization reaction can be carried out in any of batch, semi-continuous and continuous methods. Furthermore, the polymerization can be carried out in two or more stages having different reaction conditions. The molecular weight of the resulting propylene copolymer can be adjusted by allowing hydrogen or the like to be present in the polymerization system, changing the polymerization temperature, or using the component (C).

  In particular, hydrogen can be said to be a preferable additive because it can improve the polymerization activity of the catalyst and increase or decrease the molecular weight of the polymer. When hydrogen is added to the system, the amount is suitably about 0.00001 to 100 NL per mole of olefin. In addition to adjusting the amount of hydrogen supplied, the hydrogen concentration in the system is not limited to the method of generating or consuming hydrogen in the system, the method of separating hydrogen using a membrane, It can also be adjusted by releasing the gas out of the system.

  The production method of the present invention may be carried out by adding an antistatic agent to the system during the polymerization. Antistatic agents include polypropylene glycol, polypropylene glycol distearate, ethylenediamine-PEG-PPG-block copolymer, stearyl diethanolamine, lauryl diethanolamine, alkyldiethanolamide, polyoxyalkylene (eg polyethylene glycol, polypropylene glycol, polyethylene glycol block copolymer) For example, polyoxyalkylene (PEG-PPG-PEG) is preferable. In these antistatic agents, the ratio (g / mol) of the mass (g) to 1 mol of the transition metal atom (M) in the transition metal compound (A) is usually 100 to 10,000, preferably 100 to 1,000. Used in various amounts.

  For the propylene-based copolymer obtained by the production method of the present invention, after the synthesis by the above method, a post-treatment step such as a known catalyst deactivation treatment step, a catalyst residue removal step, a drying step, etc., if necessary May be done.

  According to the method for producing a propylene-based copolymer of the present invention, the molecular weight of the resulting polymer (copolymer) tends to be higher than when propylene is homopolymerized in the presence of the olefin polymerization catalyst. It can be seen.

<Olefin A>
In the production method of the present invention, the olefin supplied to the polymerization reaction together with propylene is preferably at least one olefin A selected from ethylene and an α-olefin having 4 to 30 carbon atoms.

  As the olefin A, at least one selected from ethylene and an α-olefin having 4 to 20 carbon atoms is more preferable, and at least one selected from ethylene and an α-olefin having 4 to 10 carbon atoms is particularly preferable.

  As said alpha olefin, a linear or branched alpha olefin is mentioned. Examples of the linear or branched α-olefin include 1-butene, 2-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, and 3-methyl. Examples include -1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, and 1-icocene.

  Moreover, at least 1 sort (s) chosen from the cyclic olefin, the olefin which has a polar group, a terminal hydroxylated vinyl compound, and an aromatic vinyl compound can coexist in a reaction system, and polymerization can also be advanced. It is also possible to use polyene in combination. Further, other components such as vinylcyclohexane may be copolymerized without departing from the spirit of the present invention.

  Examples of the cyclic olefin include cyclopentene, cycloheptene, norbornene, 5-methyl-2-norbornene, tetracyclododecene, 2-methyl-1,4,5,8-dimethano-1,2,3,4,4a, 5,8,8a-octahydronaphthalene.

As the olefin having a polar group, for example,
Α, β-unsaturated carboxylic acids such as acrylic acid, methacrylic acid, fumaric acid, maleic anhydride, itaconic acid, itaconic anhydride, bicyclo (2,2,1) -5-heptene-2,3-dicarboxylic anhydride Acids and their metal salts such as sodium, potassium, lithium, zinc, magnesium, calcium, and aluminum salts;
Methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, methacrylic acid α, β-unsaturated carboxylic acid esters such as n-propyl, isopropyl methacrylate, n-butyl methacrylate, and isobutyl methacrylate;
Vinyl esters such as vinyl acetate, vinyl propionate, vinyl caproate, vinyl caprate, vinyl laurate, vinyl stearate, vinyl trifluoroacetate;
Unsaturated glycidyl such as glycidyl acrylate, glycidyl methacrylate, monoglycidyl itaconate;
Is mentioned.

  Examples of the terminal hydroxylated vinyl compound include hydroxyl-1-butene, hydroxyl-1-pentene, hydroxyl-1-hexene, hydroxyl-1-octene, hydroxyl-1-decene, hydroxyl-1- Linear terminal hydroxylated vinyl compounds such as undecene, hydroxylated 1-dodecene, hydroxylated 1-tetradecene, hydroxylated 1-hexadecene, hydroxylated 1-octadecene, hydroxylated 1-eicocene; -3-methyl-1-butene, hydroxyl-3-methyl-1-pentene, hydroxyl-4-methyl-1-pentene, hydroxyl-3-ethyl-1-pentene, hydroxyl-4,4-dimethyl -1-pentene, hydroxyl-4-methyl-1-hexene, hydroxyl-4,4-dimethyl-1-hexene, hydroxyl-4-ethyl-1-hexene, hydroxyl-3-ethyl-1-hexene Branched terminal hydroxyl acid such as Vinyl compounds.

  Examples of the aromatic vinyl compound include styrene; o-methyl styrene, m-methyl styrene, p-methyl styrene, o, p-dimethyl styrene, o-ethyl styrene, m-ethyl styrene, p-ethyl styrene, and the like. Or polyalkylstyrene; methoxystyrene, ethoxystyrene, vinyl benzoic acid, methyl vinyl benzoate, vinyl benzyl acetate, hydroxystyrene, o-chlorostyrene, p-chlorostyrene, divinylbenzene, and other functional group-containing styrene derivatives; 3-phenyl Examples include propylene, 4-phenylpropylene, and α-methylstyrene.

  The polyene is preferably selected from diene and triene. It is also a preferred embodiment that polyene is used in the range of 0.0001 to 1 mol% with respect to the total olefin supplied to the polymerization reaction.

  Examples of the dienes include 1,4-pentadiene, 1,5-hexadiene, 1,4-hexadiene, 1,4-octadiene, 1,5-octadiene, 1,6-octadiene, 1,7-octadiene, 1, Α, ω-non-conjugated dienes such as 9-decadiene; non-conjugated such as ethylidene norbornene, vinyl norbornene, dicyclopentadiene, 7-methyl-1,6-octadiene, 4-ethylidene-8-methyl-1,7-nonadiene Diene; conjugated dienes such as butadiene and isoprene are exemplified. Among these, α, ω-nonconjugated dienes and dienes having a norbornene skeleton are preferable.

  Examples of the triene include 6,10-dimethyl-1,5,9-undecatriene, 4,8-dimethyl-1,4,8-decatriene, 5,9-dimethyl-1,4,8-decatriene, 6,9-dimethyl-1,5,8-decatriene, 6,8,9-trimethyl-1,5,8-decatriene, 6-ethyl-10-methyl-1,5,9-undecatriene, 4- Ethylidene-1,6, -octadiene, 7-methyl-4-ethylidene-1,6-octadiene, 4-ethylidene-8-methyl-1,7-nonadiene (EMND), 7-methyl-4-ethylidene-1, 6-nonadiene, 7-ethyl-4-ethylidene-1,6-nonadiene, 6,7-dimethyl-4-ethylidene-1,6-octadiene, 6,7-dimethyl-4-ethylidene-1,6-nonadiene, 4-ethylidene-1,6-decadiene, 7-methyl-4-ethylidene-1,6-decadiene, 7-methyl-6-propyl-4-ethylidene-1,6-octadiene, 4-ethylidene-1,7- Nonadiene, 8-methyl-4-ethylidene-1,7-nonadiene, 4-ethylidene-1,7-undecane Nonconjugated trienes such as ene; include trienes such as 1,3,5-hexatriene. Among these, non-conjugated triene having a double bond at the terminal, 4,8-dimethyl-1,4,8-decatriene, 4-ethylidene-8-methyl-1,7-nonadiene (EMND) is preferable.

  Each of the diene or triene may be used alone or in combination of two or more. A combination of diene and triene may also be used. Among the polyenes, α, ω-nonconjugated dienes and polyenes having a norbornene skeleton are particularly preferable.

More preferably, at least one of the olefins A is at least one selected from ethylene, 1-butene, 1-hexene, 4-methyl-1-pentene and 1-octene, and at least one of the olefins A is More preferably, it is ethylene. In the case of copolymerization, the copolymerization of propylene and ethylene is most preferred.
The use ratio of propylene and the olefin A is propylene: olefin A (molar ratio) and is usually 1:10 to 5000: 1, preferably 1: 5 to 1000: 1.

[Propylene copolymer]
As one aspect | mode of the propylene-type copolymer manufactured by the manufacturing method of this invention, the structural unit derived from propylene is 5-99 mol%, Preferably it is 10-99 mol%, More preferably, it is the range of 30-95 mol%. The propylene-type copolymer contained in is mentioned. The propylene copolymer contains 1 to 90 mol%, preferably 1 to 80 mol%, more preferably 2 to 70 mol% of a structural unit derived from olefin A. However, the total of the content of the structural unit derived from propylene and the content of the structural unit derived from olefin A is 100 mol%. Further, other structural units may be included without departing from the spirit of the present invention. These contents can be measured by nuclear magnetic resonance spectroscopy or, if there is a reference substance, infrared spectroscopy.

  Among propylene copolymers, propylene / ethylene copolymers, propylene / 1-butene copolymers, propylene / ethylene / 1-butene copolymers, propylene / 1-octene polymers, propylene / 1-hexene polymers. , Propylene / 4-methyl-1-pentene polymer, propylene / ethylene / 1-octene polymer, propylene / ethylene / 1-hexene polymer, and propylene / ethylene / 4-methyl-1-pentene polymer are particularly preferable. Moreover, what is called a block copolymer (impact copolymer) obtained by mixing or manufacturing continuously 2 or more types chosen from these polymers may be sufficient.

  In the propylene-based copolymer, the weight average molecular weight measured by a gel permeation chromatography (GPC) method is preferably 10,000 to 5,000,000, more preferably 40,000 to 4,000,000, and further preferably 50,000 to 300. 10,000, even more preferably 50,000 to 1,000,000, particularly preferably 80,000 to 500,000, and most preferably 90,000 to 400,000. The molecular weight distribution (Mw / Mn), which is the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn), is preferably 1.0 to 8.0, more preferably 1.0 to 6.0, particularly preferably. Is 1.5 to 5.0.

  In the propylene-based copolymer, the intrinsic viscosity [η] is preferably 0.1 to 15 dl / g, more preferably 0.5 to 12 dl / g, still more preferably 0.5 to 10 dl / g, particularly preferably. 0.7 to 10 dl / g, most preferably 0.7 to 8 dl / g.

  EXAMPLES Hereinafter, although this invention is demonstrated further more concretely based on an Example, this invention is not limited to these Examples. Unless otherwise specified, all examples were performed using a dry solvent under a dry nitrogen atmosphere.

[Measurement methods for various physical properties]
Ethylene content in propylene / ethylene copolymer Using Fourier transform infrared spectrophotometer FT / IR-610 manufactured by JASCO Corporation, the area near roll vibration 1155 cm ⁻¹ based on the methyl group of propylene and C—H stretching vibration Then, the absorbance in the vicinity of 4325 cm ⁻¹ was obtained, and the ethylene content in the propylene / ethylene copolymer was calculated from the ratio by a calibration curve. A calibration curve was prepared using a standard sample standardized by ¹³ C-NMR.

Intrinsic viscosity ([η])
Using an automatic kinematic viscosity measuring device VMR-053PC and a modified Ubbelohde type capillary viscometer manufactured by Kouaisha Co., Ltd., decalin and specific viscosity ηsp at 135 ° C. were determined, and the intrinsic viscosity ([η]) was calculated from the following formula.
[Η] = ηsp / {C (1 + K · ηsp)} (C: solution concentration [g / dl], K: constant)

Weight average molecular weight (Mw), number average molecular weight (Mn)
Using a gel permeation chromatograph HLC-8321GPC / HT type (manufactured by Tosoh Corporation), measurement was performed by moving 0.4 ml of a sample solution having a concentration of 0.1 wt% at a flow rate of 1.0 ml / min. Standard polystyrene was calculated as a molecular weight converted to each polymer using Tosoh Corporation.

Separation columns: TSKgel GMH6-HT and TSKgel GMH6-HTL
(Each inner diameter is 7.5mm and length is 300mm)
Column temperature: 140 ° C
Mobile phase: o-dichlorobenzene (containing 0.025% BHT)
Detector: Differential refractometer

Zirconium content in supported catalyst The zirconium content in the supported catalyst was measured using an ICP emission spectroscopic analyzer (ICPS-8100 type) manufactured by Shimadzu Corporation. The sample was wet-decomposed with sulfuric acid and nitric acid, and then a fixed volume (including filtration and dilution as necessary) was used as a test solution, and quantification was performed from a calibration curve prepared using a standard sample with a known concentration.

Aluminum content in the carrier The aluminum content in the carrier was measured by subjecting the carrier particles to ICP emission spectroscopy (ICP-AES) using ICPS (registered trademark) -8100 manufactured by Shimadzu Corporation.

Solubility of carrier When a solid polyaluminoxane composition is used as a carrier, the solubility of the solid polyaluminoxane composition in n-hexane and toluene at 25 ° C is measured according to the method described in JP-B-7-42301. Carried out. Specifically, the solubility of the dried solid polyaluminoxane composition in the solvent was measured.

The solubility in n-hexane was measured as follows. First, 2 g of a solid polyaluminoxane composition was added to 50 mL of n-hexane maintained at 25 ° C., followed by stirring for 2 hours. Subsequently, the solution part was separated using a G-4 glass filter, The aluminum concentration in the filtrate was measured. The measured aluminum concentration was determined by: The dissolution ratio obtained by this method was determined as the ratio of aluminum atoms present in the filtrate to the amount of aluminum atoms corresponding to 2 g of the solid polyaluminoxane composition used as a sample. The solubility of toluene was measured by replacing the hexane with toluene.
In addition, when drying a solid polyaluminoxane composition, it dried under reduced pressure at 25 degreeC and made the end point of drying the time when a weight change was not recognized.

Volume-based median diameter D50 and particle size distribution of the support The volume-based median diameter (median diameter, D50) and particle size distribution of the solid polyaluminoxane composition are obtained by using Microtrac MT3300EX II manufactured by Microtrac, and laser diffraction and scattering. Obtained by law. For the particle size distribution measurement, a sample in which the solid polyaluminoxane composition was previously deactivated in a wet desiccator under nitrogen flow was used. Methanol was mainly used as the dispersion medium.

Uniformity of carrier particles The uniformity of carrier particles was evaluated by the uniformity index represented by the following formula.
Uniformity index = ΣXi | D50−Di | / D50ΣXi
[Wherein, Xi represents a histogram value of particle i in particle size distribution measurement, D50 represents a volume-based median diameter, and Di represents a volume-based diameter of particle i. ]
Xi, D50 and Di of the carrier particles were measured by a laser diffraction / scattering method using MT3300EX II manufactured by Microtrac.
For the measurement, a sample in which the solid polyaluminoxane composition was previously deactivated in a wet desiccator under nitrogen flow was used. Methanol was mainly used as the dispersion medium.

[Synthesis of transition metal compounds]
[Synthesis Example 1]
Synthesis of diphenylmethylene (3-tert-butyl-5-ethylcyclopentadienyl) (2,7- ditert-butylfluorenyl ) zirconium dichloride (hereinafter also referred to as “catalyst A”) Synthesis of Patent No. 4823910 Catalyst A was synthesized according to Example 4.

[Synthesis Example 2]
Synthesis of diphenylmethylene (3-tert-butyl-5-methylcyclopentadienyl) (2,7-ditert-butylfluorenyl) zirconium dichloride (hereinafter also referred to as “catalyst B”)
Catalyst B was synthesized according to Example 3c of WO2004 / 087775.

[Synthesis Example 3]
Synthesis of dibenzylmethylene (cyclopentadienyl) (2,7-diphenyl-3,6- ditert-butylfluorenyl ) zirconium dichloride (hereinafter also referred to as “catalyst C”) Synthesis Example 1 of Patent No. 5105772 According to the procedure, catalyst C was synthesized.

[Preparation of supported catalyst (also referred to as “solid catalyst”)]
[Preparation Example 1]
The solid polyaluminoxane composition to be used was prepared based on a known method (International Publication No. 2014/123212). Specifically, after adding 57 mL of toluene and a 10 wt% polymethylaluminoxane toluene solution (Al concentration = 3.04 mmol / mL, 35 mL, 106.3 mmol) manufactured by Albemarle to a 200 mL glass flask equipped with a stirrer, the mixture was stirred. The temperature was raised to 70 ° C. Subsequently, a toluene solution (18.6 mL) of acetophenone (1.79 g, 14.9 mmol) was added over 120 minutes. After the addition, the mixture was stirred at 70 ° C. for 60 minutes, heated to 95 ° C. at a rate of temperature increase of 1.0 ° C./min, and reacted at 95 ° C. for 8 hours. After cooling to 80 ° C., the supernatant (75 mL) was removed by decantation. The precipitated solid polyaluminoxane was washed three times at 80 ° C. with toluene (45 mL), and then toluene was added to adjust the total amount to 100 mL to obtain a toluene slurry of the solid polyaluminoxane composition. The obtained slurry was filtered and the powder on the filter was washed 3 times with 20 mL of dehydrated hexane. The washed powder was dried under reduced pressure for 6 hours to obtain a solid polyaluminoxane composition. When the aluminum content in the obtained solid polyaluminoxane composition was measured, the aluminum content was 44.4% by mass.

  The solubility of the obtained solid polyaluminoxane composition in the solvent was measured. The solubility in n-hexane at 25 ° C. was less than 0.04 mol%, and the solubility in toluene was less than 0.05 mol%.

Further, the particle size distribution was measured. The volume-based median diameter D50 was 29.7 μm, and the uniformity index was 0.247.
Next, a stirring bar was attached to a 100 ml three-necked flask sufficiently purged with nitrogen, to which 0.5062 g of the solid polyaluminoxane composition and 30 mL of dehydrated toluene were added, and the liquid temperature was heated to 35 ° C. . To this was added 5 mL of a toluene solution containing 20.3 mg of Catalyst A obtained in Synthesis Example 1, and the mixture was stirred at 35 ° C. for 1 hour. The obtained slurry was filtered, and the powder on the filter was washed once with 10 ml of dehydrated toluene and then three times with 10 ml of dehydrated hexane. The powder after washing was dried under reduced pressure to obtain a solid catalyst consisting of 0.4735 g of powder, with the end point being no change in weight. A portion of the dried solid catalyst was weighed, gradually deactivated in air, and analyzed by an ICP emission spectroscopic analyzer. The zirconium content in the solid catalyst was 0.404% by mass. The zirconium complex content of the solid catalyst (olefin polymerization catalyst) was 3.34% by mass. The remaining supported catalyst other than that used in the analysis was mixed with mineral oil to obtain a slurry having a supported catalyst concentration of 10.0 wt%.

[Preparation Example 2]
The solid polyaluminoxane composition to be used was prepared based on a known method (International Publication No. 2014/123212). Specifically, 55 mL of toluene and a 20 wt% polymethylaluminoxane toluene solution (Al concentration = 2.97 mmol / mL, 192 mL, 570.2 mmol) manufactured by Albemarle were added to a 1 L glass autoclave equipped with a stirrer, and then stirred. The temperature was raised to 70 ° C. Subsequently, a toluene solution (24.5 mL) of benzaldehyde (9.10 g, 85.8 mmol) was added over 80 minutes. After the addition, the mixture was stirred at 70 ° C. for 10 minutes, then heated to 140 ° C. at a rate of 1.0 ° C./min, and reacted at 140 ° C. for 4 hours. After cooling to 80 ° C., the supernatant (125 mL) was removed by decantation. The precipitated solid polyaluminoxane was washed twice with toluene (400 mL) at 80 ° C., and then toluene was added to adjust the total amount to 300 mL to obtain a toluene slurry of the solid polyaluminoxane composition.

  The obtained slurry was filtered and the powder on the filter was washed 3 times with 20 mL of dehydrated hexane. The washed powder was dried under reduced pressure for 6 hours to obtain a solid polyaluminoxane composition. When the aluminum content in the obtained solid polyaluminoxane composition was measured, the aluminum content was 43.3% by mass.

  The solubility of the obtained solid polyaluminoxane composition in the solvent was measured. The solubility in n-hexane at 25 ° C. was less than 0.05 mol%, and the solubility in toluene was less than 0.05 mol%.

Further, the particle size distribution was measured. The volume-based median diameter (D50) was 22.7 μm, and the uniformity index was 0.278.
Next, a toluene slurry (Al concentration = 1.65 mmol / mL, 2.45 mL, 4.05 mmol) of the solid polymethylaluminoxane composition and 16.5 mL of toluene were collected in a reactor. To this was added 1.00 mL of a toluene solution containing 10.00 mg of Catalyst B obtained in Synthesis Example 2, and the mixture was stirred at room temperature for 1 hour. The obtained slurry was filtered, and the powder on the filter was washed twice with 5 mL of dehydrated toluene and then twice with 5 mL of dehydrated hexane. The washed powder was dried under reduced pressure for 2 hours to obtain a supported catalyst composed of 0.218 g of powder. This was mixed with mineral oil to obtain a slurry having a supported catalyst concentration of 4.98 wt%.

[Preparation Example 3]
The toluene slurry (Al concentration = 1.65 mmol / mL, 2.45 mL, 4.05 mmol) of the solid polymethylaluminoxane composition obtained in Preparation Example 2 and 16.0 mL of toluene were collected in a reactor. To this was added 1.00 mL of a toluene solution containing 10.0 mg of Catalyst C obtained in Synthesis Example 3, and the mixture was stirred at room temperature for 1 hour. The obtained slurry was filtered, and the powder on the filter was washed twice with 5 mL of dehydrated toluene and then twice with 5 mL of dehydrated hexane. The washed powder was dried under reduced pressure for 2 hours to obtain a supported catalyst composed of 0.242 g of powder. This was mixed with mineral oil to obtain a slurry having a supported catalyst concentration of 5.00 wt%.

[Preparation Example 4]
The solid polyaluminoxane composition to be used was prepared based on a known method (International Publication No. 2014/123212). Specifically, 83 mL of toluene and a 20 wt% polymethylaluminoxane toluene solution (Al concentration = 3.01 mmol / mL, 167 mL, 502.7 mmol) manufactured by Albemarle were added to a 1 L glass autoclave equipped with a stirrer, and then stirred. The temperature was raised to 70 ° C. Subsequently, a toluene solution (21.5 mL) of 2-phenyl-2-propanol (10.2 g, 75.3 mmol) was added over 80 minutes. After the addition, the mixture was stirred at 70 ° C. for 10 minutes, then heated to 140 ° C. at a rate of 1.0 ° C./min, and reacted at 140 ° C. for 4 hours. After cooling to 80 ° C., the supernatant (125 mL) was removed by decantation. The precipitated solid polyaluminoxane was washed twice with toluene (400 mL) at 80 ° C., and then toluene was added to adjust the total amount to 300 mL to obtain a toluene slurry of the solid polyaluminoxane composition.

  The obtained slurry was filtered and the powder on the filter was washed 3 times with 20 mL of dehydrated hexane. The washed powder was dried under reduced pressure for 6 hours to obtain a solid polyaluminoxane composition. When the aluminum content in the obtained solid polyaluminoxane composition was measured, the aluminum content was 44.3% by mass.

  The solubility of the obtained solid polyaluminoxane composition in the solvent was measured. The solubility in n-hexane at 25 ° C. was less than 0.05 mol%, and the solubility in toluene was less than 0.05 mol%.

Further, the particle size distribution was measured. The volume-based median diameter (D50) was 26.9 μm, and the uniformity index was 0.229.
Next, a toluene slurry (Al concentration = 1.77 mmol / mL, 2.30 mL, 4.06 mmol) of the solid polymethylaluminoxane composition and 16.7 mL of toluene were collected in a reactor. To this was added 1.00 mL of a toluene solution containing 10.0 mg of the catalyst B obtained in Synthesis Example 2, and the mixture was stirred at room temperature for 1 hour. The obtained slurry was filtered, and the powder on the filter was washed twice with 5 mL of dehydrated toluene and then twice with 5 mL of dehydrated hexane. The washed powder was dried under reduced pressure for 2 hours to obtain a supported catalyst composed of 0.221 g of powder. This was mixed with mineral oil to obtain a slurry having a supported catalyst concentration of 5.01 wt%.

[Comparative Preparation Example 1-1]
A stirring bar was attached to a 100 mL three-necked flask sufficiently purged with nitrogen, and 5.00 g of silica gel (AGC S-Tech Co., Ltd. H-121) dried at 180 ° C. under a nitrogen stream for 6 hours was added thereto. To this, 64 mL of dehydrated toluene and 40 mL of a toluene solution of methylaluminoxane (manufactured by Albemarle, 10% by weight) were added at room temperature, followed by stirring at 95 ° C. for 4 hours. The obtained slurry was filtered with a filter, and the filter-like powder was washed with 25 mL of dehydrated toluene three times and then with 25 mL of dehydrated hexane three times. The washed powder was dried under reduced pressure to obtain silica-supported methylaluminoxane with the point that there was no weight change as the end point. A portion of the dried silica-supported methylaluminoxane was weighed, gradually deactivated in air, and analyzed by an ICP emission spectroscopic analyzer. The Al concentration in the obtained silica-supported methylaluminoxane was 16.6% by mass.

  A stirring bar was attached to a 100 ml three-necked flask thoroughly purged with nitrogen, and 0.996 g of silica-supported methylaluminoxane (Al concentration 16.6% by mass) was added thereto. To this was added 30 ml of dehydrated toluene at room temperature, and 20 ml of a toluene solution containing 20.0 mg of catalyst A obtained in Synthesis Example 1 was added with stirring, followed by stirring for 1 hour. The obtained slurry was filtered, and the powder on the filter was washed once with 10 ml of dehydrated toluene and then three times with 10 ml of dehydrated hexane. The washed powder was dried under reduced pressure to obtain a solid catalyst consisting of 0.917 g of powder with the end point being no change in weight. A portion of the dried solid catalyst was weighed, gradually deactivated in air, and analyzed by an ICP emission spectroscopic analyzer. The zirconium content in the supported catalyst was 0.239% by mass. The zirconium complex content of the solid catalyst (olefin polymerization catalyst) was 1.97% by mass. The remaining solid catalyst other than that used in the analysis was mixed with mineral oil to obtain a slurry having a supported catalyst concentration of 10.0 wt%.

[Comparative Preparation Example 1-2]
According to Example 3 of JP-T-2005-538203, a toluene slurry of solid polyaluminoxane (hereinafter also referred to as “support”) was prepared. Specifically, a solution prepared by adding 120 mL of toluene to 1.62 g of bisphenol A was prepared, and 23.9 mL of a 20% by weight polymethylaluminoxane toluene solution manufactured by Albemarle was added to a 200 mL glass flask equipped with a stirrer, and then prepared first. The bisphenol A toluene solution was added with stirring at room temperature. After the addition, the temperature was raised to 55 ° C. and stirred for 20 hours. The obtained solid polyaluminoxane was filtered under a nitrogen atmosphere, dried under reduced pressure, and the point where there was no weight change was set as the end point. The Al concentration in the support was 33% by mass. The volume-based median diameter D50 was 16.1 μm, and the uniformity index was 0.826. A stirring bar was attached to a 100 ml three-necked flask thoroughly purged with nitrogen, and 0.8022 g of solid polyaluminoxane and 30 mL of dehydrated toluene were added thereto, and the liquid temperature was heated to 35 ° C. To this was added 5 mL of a toluene solution containing 32.3 mg of Catalyst A obtained in Synthesis Example 1, and the mixture was stirred at 35 ° C. for 1 hour. The obtained slurry was filtered, and the powder on the filter was washed once with 10 ml of dehydrated toluene and then three times with 10 ml of dehydrated hexane. The washed powder was dried under reduced pressure to obtain a supported catalyst composed of 0.6698 g of powder, with the end point being no change in weight. A portion of the dried solid catalyst was weighed, gradually deactivated in air, and analyzed by an ICP emission spectroscopic analyzer. The zirconium content in the solid catalyst was 0.498% by mass. The zirconium complex content of the solid catalyst (olefin polymerization catalyst) was 4.11% by mass. The remaining solid catalyst other than that used in the analysis was mixed with mineral oil to obtain a slurry having a supported catalyst concentration of 6.65 wt%.

[Propylene / ethylene copolymer]
[Example 1]
A SUS autoclave with an internal volume of 3,400 ml sufficiently purged with nitrogen was charged with 1.0 L of liquid propylene, heated to 55 ° C. with sufficient stirring, and then pressurized with ethylene gas to adjust the internal pressure of the autoclave to 3.0 MPaG. Subsequently, a mixed solution of 3 ml of dehydrated hexane and 1 ml of a hexane solution of triisobutylaluminum (Al = 0.5M) was added to a catalyst insertion pot with a sufficient nitrogen substitution and an internal volume of 30 ml mounted on the autoclave. Pressure was inserted into the autoclave with nitrogen. Next, a mixture of 106 mg of the solid catalyst slurry prepared in Preparation Example 1 and 1 ml of hexane solution of triisobutylaluminum (Al = 0.5M) was added to the catalyst insertion pot, and this was pressure-inserted into the autoclave with nitrogen and polymerized. Started. After 10 minutes of polymerization, a small amount of methanol was added to stop the polymerization. The polymer obtained was added to a large excess of methanol to which hydrochloric acid was added to deash, and the polymer was filtered off. The polymer was then dried under reduced pressure at 80 ° C. for 10 hours. The results are shown in Table 1.

[Example 2]
Polymerization was carried out in the same manner as in Example 1 except that 200.8 mg of the solid catalyst slurry prepared in Preparation Example 2 was used as the solid catalyst. The results are shown in Table 1.

[Example 3]
Polymerization was carried out in the same manner as in Example 1 except that 205.5 mg of the solid catalyst slurry prepared in Preparation Example 3 was used as the solid catalyst. The results are shown in Table 1.

[Example 4]
Polymerization was carried out in the same manner as in Example 1 except that 199.1 mg of the solid catalyst slurry prepared in Preparation Example 4 was used as the solid catalyst. The results are shown in Table 1.

[Comparative Example 1-1]
A SUS autoclave with an internal volume of 2,000 ml sufficiently purged with nitrogen was charged with 0.6 L of liquid propylene, heated to 55 ° C. with sufficient stirring, and then pressurized with ethylene gas to adjust the internal pressure of the autoclave to 2.9 MPaG. Subsequently, a mixed solution of 4 ml of dehydrated hexane and 1 ml of a hexane solution of triisobutylaluminum (Al = 1.0M) was added to a catalyst insertion pot with an internal volume of 30 ml that had been sufficiently purged with nitrogen and was mounted on an autoclave. Pressure was inserted into the autoclave with nitrogen. Next, a mixture of 349 mg of the solid catalyst slurry prepared in Comparative Preparation Example 1-1 and 1.0 ml of hexane solution of triisobutylaluminum (Al = 1.0 M) was added to the catalyst insertion pot, and this was pressurized to the autoclave with nitrogen. Insertion started the polymerization. After 10 minutes of polymerization, a small amount of methanol was added to stop the polymerization. The polymer obtained was added to a large excess of methanol to which hydrochloric acid was added to deash, and the polymer was filtered off. The polymer was then dried under reduced pressure at 80 ° C. for 10 hours. The results are shown in Table 1.

[Comparative Example 1-2]
The same operation as in Example 1 was performed except that 0.176 g of the solid catalyst slurry obtained in Comparative Preparation Example 1-2 was used instead of the supported catalyst slurry obtained in Preparation Example 1. The results are shown in Table 1.

  Example 1 using the catalyst A as the transition metal compound (A) and the support (B) (solid polyaluminoxane composition (B) having an aluminum content of 36% or more) as the support was used as the transition metal compound (A). Compared to Comparative Example 1-1 using the same catalyst A but using a silica support as a support, and Comparative Example 1-2 using a solid polyaluminoxane composition having a low aluminum content as a support, It can be seen that [η] is large. Comparison between Example 1 and Comparative Examples 1-1 and 1-2, and the carrier (B) (solid polyaluminoxane composition (B)) described in “Mode for Carrying Out the Invention” According to the estimation mechanism of the manifestation of the effect of increasing the molecular weight based on use, in Examples 2 to 4 in which the catalyst B or the catalyst C was used as the transition metal compound (A), the support was changed from the support (B) to a silica support or the like When changed, it is presumed that [η] of the obtained polymer becomes small.

Claims (8)

Production of propylene / α-olefin copolymer having a polymerization step of polymerizing propylene and α-olefin (excluding propylene) in the presence of a catalyst for olefin polymerization including transition metal compound (A) and carrier (B). A method,
The transition metal compound (A) is represented by the following general formula [I]:

[In the formula [I], R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ and R ¹⁴ are each Independently a hydrogen atom, a hydrocarbon group, a heteroatom-containing hydrocarbon group or a silicon-containing group, and any two substituents of R ¹ to R ⁴ are bonded to each other to form a ring. Of the substituents R ⁵ to R ¹² , any two substituents may be bonded to each other to form a ring, and R ¹³ and R ¹⁴ are bonded to each other to form a ring. You may,
Y is a carbon atom, a silicon atom or a germanium atom;
M is a Group 4 transition metal atom,
j is an integer of 1 to 4,
Q is a halogen atom, a hydrocarbon group, an anionic ligand, or a neutral ligand that can be coordinated by a lone electron pair. When j is an integer of 2 or more, Q is selected in the same or different combination. ]
The carrier (B) comprises a solid polyaluminoxane composition containing a structural unit represented by the following formula [II] and having an aluminum content of 36% by mass or more,

The method for producing a propylene / α-olefin copolymer in which the transition metal compound (A) is supported on the carrier (B). In the general formula [I], R ¹ , R ³ , R ¹³ and R ¹⁴ are each independently a hydrocarbon group having 1 to 10 carbon atoms, and R ⁶ , R ⁷ , R ¹⁰ and R ¹¹ are each independently The hydrogen atom or hydrocarbon group, R ² , R ⁴ , R ⁵ , R ⁸ , R ⁹ and R ¹² are hydrogen atoms, Y is a carbon atom, and M is a zirconium atom. A process for producing a propylene / α-olefin copolymer. The propylene / α-olefin copolymer according to claim 1 or 2, wherein, in the general formula [I], R ³ is a hydrocarbon group containing a quaternary carbon, and R ¹³ and R ¹⁴ are each independently an aryl group. Manufacturing method of coalescence.   The method for producing a propylene / α-olefin copolymer according to any one of claims 1 to 3, wherein the α-olefin is ethylene.   The method for producing a propylene / α-olefin copolymer according to any one of claims 1 to 4, wherein the polymerization method in the polymerization step is bulk polymerization using propylene as a solvent.   The propylene / α-olefin copolymer according to any one of claims 1 to 5, wherein the solid polyaluminoxane composition is in the form of particles, and the volume-based median diameter (D50) is in the range of 0.1 to 100 µm. A method for producing a polymer. The method for producing a propylene / α-olefin copolymer according to any one of claims 1 to 6, wherein the solid polyaluminoxane composition satisfies the following requirements (i) and (ii). Requirement (i): The solubility in n-hexane at 25 ° C. measured by the following method (i) is less than 2.0 mol%. Requirement (ii): The solubility in toluene at 25 ° C. measured by the following method (ii) is less than 2.0 mol%.
[Method (i)]
2 g of the solid polyaluminoxane composition is added to 50 mL of n-hexane maintained at 25 ° C., followed by stirring for 2 hours, followed by separation into a filtrate and a residue by filtration, and the aluminum in the filtrate. The concentration is measured using ICP emission spectroscopy (ICP-AES), and the solubility is determined as the ratio of aluminum atoms present in the filtrate to the amount of aluminum atoms corresponding to 2 g of the solid polyaluminoxane composition.
[Method (ii)]
Solubility is calculated | required by the method similar to the said method (i) except using toluene instead of n-hexane. The propylene / α- according to any one of claims 1 to 7, wherein the solid polyaluminoxane composition is particulate, and a uniformity index represented by the following formula of the composition is 0.45 or less. A method for producing an olefin copolymer.
Uniformity index = ΣXi | D50−Di | / D50ΣXi
[Wherein, Xi represents a histogram value of particle i in particle size distribution measurement, D50 represents a volume-based median diameter, and Di represents a volume-based diameter of particle i. ]