Catalyst for olefin polymerisation and process for producing olefin polymers in the presence of the catalyst

Abstract

To provide a catalyst for olefin multimerization that ensures the selectivity and / or production efficiency of a specific olefin multimer coupled with the reduction of by-products in olefin polymerization, and a method for producing an olefin multimer using the same.SOLUTION: A catalyst for olefin multimerization includes (A) a chromium compound, (B) an amine compound, and (C) an organometallic compound of a specific structure. In the presence of the catalyst for olefin multimerization, an olefin multimerization reaction is performed.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an olefin polymerization catalyst having excellent activity and high selectivity and / or production efficiency for specific olefin polymers, and a process for producing olefin polymers in the presence of the olefin polymerization catalyst. [Background technology]

[0002] α-olefins are important compounds widely used industrially, for example, as raw materials for polyolefins. 1-hexene and 1-octene, for example, are in high demand as raw materials for polyolefins. Industrialized methods for producing α-olefins include those using organoaluminum or transition metal compounds as catalysts. However, these industrialized methods typically produce a mixture of many different α-olefins. This can make it difficult to respond flexibly to changes in the market conditions for each component. Therefore, a highly selective production method for the desired α-olefin is desirable.

[0003] In recent years, the present inventors have reported catalysts that can selectively produce 1-hexene or 1-octene, for example, through the trimerization or tetramerization reaction of ethylene, using catalysts that combine a transition metal complex compound or a chromium compound having a phenoxyimine ligand with a specific amine compound (e.g., Patent Documents 1 to 3).

[0004] It has also been reported that the performance of olefin oligomerization reactions can be improved by combining a catalyst in which the above-mentioned chromium compound is combined with a specific amine compound with a compound such as a specific organometallic compound (Patent Documents 4 and 5).

[0005] Furthermore, chromium-based catalysts using a ligand containing a phosphorus atom have been disclosed as catalysts for selectively producing 1-octene (for example, Patent Documents 6 to 8). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2009 / 005003 [Patent Document 2] International Publication No. 2019 / 009390 [Patent Document 3] Japanese Patent Publication No. 2021-151993 [Patent Document 4] Patent Publication No. 2021-161122 [Patent Document 5] Patent Publication No. 2021-161123 [Patent Document 6] International Publication No. 2004 / 056479 [Patent Document 7] International Publication No. 2013 / 137676 [Patent Document 8] International Publication No. 2009 / 022770 Summary of the Invention [Problem to be solved by the invention]

[0007] The above-mentioned olefin polymers such as 1-hexene and 1-octene are products for which cost reduction is highly desired, as they are primarily used as raw materials for olefin polymers. For this reason, improvements in the catalytic activity and selectivity of the resulting olefin polymers are desired.

[0008] Furthermore, it has been reported that ethylene polymers are by-produced in the production of 1-hexene, 1-octene, and the like using the above catalysts. If these polymers adhere to the inner walls of the reactor or the heat exchanger, this can lead to a decrease in heat removal performance, which can hinder stable and long-term operation. To address the problem of ethylene polymer by-production, a known method involves increasing the reaction temperature to dissolve the ethylene polymer in a solvent. According to the inventors' studies, excessively high reaction temperatures tend to decrease catalytic activity. Therefore, it is believed that dissolving the ethylene polymer at as low a temperature as possible may potentially achieve both reaction activity and prevention of ethylene polymer adhesion to the inner walls. To achieve this, reducing the amount of ethylene polymer by-production is one strategy. This can also be considered an indicator of the selectivity of the olefin polymer.

[0009] The present invention has been made in view of these problems. That is, one object of the present invention is to provide a method for producing an olefin polymer, which has excellent catalytic activity and can minimize the amount of ethylene polymer produced as a by-product. [Means for solving the problem]

[0010] As a result of extensive research into solving the above-mentioned problems, the present inventors have found that the above-mentioned problems can be solved by using an organometallic compound having a specific halogen-containing substituent in combination with a chromium compound, an amine compound, an organometallic compound, etc. That is, the present invention is characterized by the following features.

[0011] [1] A method for producing an olefin polymer, comprising carrying out an olefin polymerization reaction in the presence of an olefin polymerization catalyst comprising the following components (A), (B), and (C): (A) chromium compounds, (B) an amine compound represented by the following general formula (1):

[0012] [ka]

[0013] (In general formula (1), R 1 ~R 4 each independently represents a hydrogen atom, a halogen atom, a hydrocarbon group, a heterocyclic compound residue, an oxygen-containing group, a nitrogen-containing group, a boron-containing group, an aluminum-containing group, a sulfur-containing group, a phosphorus-containing group, a silicon-containing group, a germanium-containing group, or a tin-containing group, and two or more of these may be linked to each other. Y is a substituent R 5 and R 6 Carbon atom with (-CR 5 R 6 -) represents the structure represented by R 5 and R 6 R each independently represents a hydrogen atom, a halogen atom, a hydrocarbon group, a heterocyclic compound residue, an oxygen-containing group, a nitrogen-containing group, a boron-containing group, an aluminum-containing group, a sulfur-containing group, a phosphorus-containing group, a silicon-containing group, a germanium-containing group, or a tin-containing group. 5 and R 6 may be linked to each other. 5 and R 6 At least one of them is R 1 ~R 4 When Z is an integer of 2 or more, the multiple Ys are each independently defined as above. Z represents an integer of 1 to 10. (C) An organometallic compound specified by the following general formula (2):

[0014] [ka]

[0015] (In general formula (2), I C + is a cation containing an atom from Group 14 or 15 of the periodic table, IA is an atom selected from group 13 elements of the periodic table, R α is a substituent containing a hydrogen atom or an atom selected from the group consisting of atoms in groups 14 to 17 of the periodic table, R h is a halogen-containing hydrocarbon group, m is a positive real number, n is 0 or a positive real number, and 2 < m ≤ 4 and m + n = 4 are satisfied.)

[0016] [2] The method for producing an olefin multimer according to [1], wherein the IA is an aluminum atom. [3] The above R h The method for producing an olefin multimer according to [1] or [2], wherein the R is a fluorine-containing hydrocarbon group. [4] R 1 is R 3 and R 4 are not linked, and R 2 is R 3 and R 4 are not linked. The method for producing an olefin multimer according to any one of [1] to [3].

[0017] [5] The method for producing an olefin multimer according to any one of [1] to [4], wherein Z is an integer of 1 to 3. [6] The method for producing an olefin multimer according to any one of [1] to [5], wherein Z is 1. [7] The method for producing an olefin multimer according to any one of [1] to [6], wherein the olefin is ethylene.

[0018] [8] An olefin multimerization catalyst containing the following components (A), (B), and (C). (A) A chromium compound, (B) An amine compound represented by the following general formula (1),

[0019] [Chemical formula]

[0020] (In the general formula (1), R 1 to R 4 each independently represents a hydrogen atom, a halogen atom, a hydrocarbon group, a heterocyclic compound residue, an oxygen-containing group, a nitrogen-containing group, a boron-containing group, an aluminum-containing group, a sulfur-containing group, a phosphorus-containing group, a silicon-containing group, a germanium-containing group, or a tin-containing group, and two or more of these may be linked to each other. Y represents a carbon atom having substituents R 5 and R 6 (-CR 5 R 6 - represented structure). R 5 and R 6 each independently represent a hydrogen atom, a halogen atom, a hydrocarbon group, a heterocyclic compound residue, an oxygen-containing group, a nitrogen-containing group, a boron-containing group, an aluminum-containing group, a sulfur-containing group, a phosphorus-containing group, a silicon-containing group, a germanium-containing group, or a tin-containing group. R 5 and R 6 may be linked to each other. R 5 and R 6 at least one of which may be linked to any of R 1 ~R 4 . When Z is an integer of 2 or more, the plurality of Ys are each independently defined as above. Z represents an integer from 1 to 10. ) (C) An organometallic compound specified by the following general formula (2)

[0021] [Chemical formula]

[0022] (In general formula (2), IC + is a cation containing a Group 14 or 15 atom of the periodic table, IA is an atom selected from Group 13 elements of the periodic table, R α is a substituent containing an atom selected from Group 14 to 17 atoms of the periodic table, R h is a halogen-containing hydrocarbon group, m is a positive real number, n is 0 or a positive real number, and 2 < m ≤ 4 and m + n = 4 are satisfied. ) [Advantages of the Invention]

[0023] According to the present invention, there are provided an olefin polymerization catalyst which has excellent activity and produces little polyolefin by-product, and a process for producing olefin polymers in the presence of the olefin polymerization catalyst. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited thereto. In the present invention, the term "olefin polymerization" means converting an olefin into a dimer to a decamer, and preferably converting an olefin into a trimer to a tetramer.

[0025] <Chromium Compounds (A)> The chromium compound serving as component (A) (hereinafter also referred to as "chromium compound (A)") is typically an inorganic salt, an organic salt, or a metal-organic complex of chromium. Specific examples of chromium compound (A) include chromium(III) chloride, chromium(II) chloride, chromium(III) bromide, chromium(II) bromide, chromium(III) iodide, chromium(II) iodide, chromium(III) fluoride, chromium(II) fluoride, chromium trichloride tristetrahydrofuran, chromium(III) 2-ethylhexanoate, chromium(III) acetylacetonate, chromium(III) trifluoroacetylacetonate, and chromium(III) hexafluoroacetylacetonate. However, chromium compound (A) is not limited to these. Among these, trivalent chromium compounds are preferred. Chromium compounds containing halogen atoms are also preferred.

[0026] <Amine compound (B)> The amine compound serving as component (B) (hereinafter also referred to as "amine compound (B)") is represented by the following general formula (1).

[0027] [ka]

[0028] In general formula (1), R 1 ~R 4are each independently a hydrogen atom, a halogen atom, a hydrocarbon group, a heterocyclic compound residue, an oxygen-containing group, a nitrogen-containing group, a boron-containing group, an aluminum-containing group, a sulfur-containing group, a phosphorus-containing group, a silicon-containing group, a germanium-containing group, or a tin-containing group, and two or more of these may be linked to each other. More specifically, R 1 ~R 4 are each independently preferably a hydrogen atom, a halogen atom, a hydrocarbon group, a heterocyclic compound residue, a hydrocarbon-substituted silyl group, a hydrocarbon-substituted siloxy group, an alkoxy group, an alkylthio group, an aryloxy group, an arylthio group, an acyl group, an ester group, a thioester group, an amido group, an imido group, an amino group, an imino group, a sulfone ester group, a sulfonamide group, a cyano group, a nitro group, a carboxyl group, a sulfo group, a mercapto group, an aluminum-containing group, or a hydroxy group. R 1 ~R 4 are identical to each other, but R 1 ~R 4 may contain one or more combinations of different groups, and R 1 ~R 4 may be different from each other.

[0029] In the general formula (1), Y is a substituent R 5 , R 6 Carbon atom with (-CR 5 R 6 -) represents the structure represented by R 5 , R 6 R are each independently, i.e., may be the same or different from each other, and represent a hydrogen atom, a halogen atom, a hydrocarbon group, a heterocyclic compound residue, an oxygen-containing group, a nitrogen-containing group, a boron-containing group, an aluminum-containing group, a sulfur-containing group, a phosphorus-containing group, a silicon-containing group, a germanium-containing group, or a tin-containing group. 5 and R 6 may be linked to each other. 5 and R 6 At least one of them is R 1 ~R 4When Z is an integer of 2 or greater, the multiple Ys are each independently defined as above. The multiple Ys may be the same as each other, or the multiple Ys may contain one or more combinations of groups that are different from each other, or the multiple Ys may be different from each other.

[0030] In general formula (1), Z represents an integer of 1 to 10. In some cases, Z is preferably 2 to 10. On the other hand, Z is preferably an integer of 1 to 3, more preferably 1 or 2, and particularly preferably 1.

[0031] Specific examples of halogen atoms include fluorine, chlorine, bromine, and iodine.

[0032] The hydrocarbon group is a group containing a hydrocarbon group as a moiety bonding to another group, and the hydrocarbon group may be substituted with another substituent. Specific examples of the hydrocarbon group include linear or branched alkyl groups having 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms, and more preferably 1 to 10 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, neopentyl, and n-hexyl; linear or branched alkenyl groups having 2 to 30 carbon atoms, preferably 2 to 20 carbon atoms, such as vinyl, allyl, and isopropenyl; linear or branched alkynyl groups having 2 to 30 carbon atoms, preferably 2 to 20 carbon atoms, such as ethynyl and propargyl; cyclic saturated hydrocarbon groups having 3 to 30 carbon atoms, preferably 3 to 20 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and adamantyl; cyclopentadienyl, indenyl, and fluorene. aryl groups having 6 to 30, preferably 6 to 20, carbon atoms, such as phenyl, naphthyl, biphenyl, terphenyl, phenanthryl, and anthracenyl; substituted aryl groups in which these aryl groups are substituted with 1 to 5 substituents selected from the group consisting of halogen atoms, alkyl groups, alkoxy groups, and amino groups having 1 to 30, preferably 1 to 20, carbon atoms, and aryl groups and aryloxy groups having 6 to 30, preferably 6 to 20, carbon atoms; aryl-substituted alkyl groups having 7 to 19 carbon atoms, such as benzyl, cumyl, diphenylethyl, and trityl; and alkylidene groups having 1 to 30, preferably 5 to 10, carbon atoms, such as benzylidene, methylidene, and ethylidene. Examples of the alkyl-substituted aryl group include alkyl-substituted aryl groups having 7 to 14 carbon atoms, such as tolyl, isopropylphenyl, t-butylphenyl, dimethylphenyl, and di-t-butylphenyl.

[0033] The hydrocarbon group may be a group in which at least one hydrogen atom of the hydrocarbon group has been substituted with a group other than a hydrocarbon group.

[0034] Examples of the group other than the hydrocarbon group that is substituted on the hydrocarbon group include at least one selected from the group consisting of a halogen atom, a heterocyclic compound residue, an oxygen-containing group, a nitrogen-containing group, a boron-containing group, a sulfur-containing group, a phosphorus-containing group, a silicon-containing group, a germanium-containing group, and a tin-containing group. Examples of the halogen-substituted hydrocarbon group include halogenated hydrocarbon groups having 1 to 30, preferably 1 to 20, carbon atoms, such as trifluoromethyl, pentafluorophenyl, and chlorophenyl.

[0035] Preferred hydrocarbon groups include linear or branched alkyl groups having 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and particularly preferably 2 to 10 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, neopentyl, n-hexyl, and adamantyl; aryl groups having 6 to 30 carbon atoms, preferably 6 to 20 carbon atoms, such as phenyl, naphthyl, biphenyl, terphenyl, phenanthryl, and anthracenyl; and substituted aryl groups in which these aryl groups are substituted with 1 to 5 substituents. The substituents in the substituted aryl groups are selected from the group consisting of halogen atoms, alkyl groups, alkoxy groups, or amino groups having 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms, and aryl or aryloxy groups having 6 to 30 carbon atoms, preferably 6 to 20 carbon atoms.

[0036] Examples of oxygen-containing groups, nitrogen-containing groups, sulfur-containing groups, and phosphorus-containing groups include groups containing at least one selected from oxygen atoms, nitrogen atoms, iron atoms, and phosphorus atoms. In the present invention, these groups are mainly classified according to the atoms that characterize the properties and bonding patterns of the groups. For example, groups whose properties and bonding patterns are characterized by oxygen atoms, such as groups consisting of only oxygen atoms and groups consisting of at least one of carbon atoms and hydrogen atoms and oxygen atoms, are classified as oxygen-containing groups. Groups containing nitrogen atoms are also classified as nitrogen-containing groups if they contain oxygen atoms and whose properties and bonding patterns are characterized by nitrogen atoms. Groups containing sulfur atoms or phosphorus atoms are similarly classified. Note that boron-containing groups, aluminum-containing groups, phosphorus-containing groups, silicon-containing groups, germanium-containing groups, and tin-containing groups, which will be described later, are also similarly classified. Among the oxygen-containing groups, nitrogen-containing groups, sulfur-containing groups and phosphorus-containing groups, the oxygen-containing groups, nitrogen-containing groups and sulfur-containing groups are preferred, and the oxygen-containing groups and nitrogen-containing groups are more preferred.

[0037] Examples of the oxygen-containing group include a hydroxy group, an alkoxy group, an aryloxy group, an ester group, an ether group, an acyl group, a carboxyl group, a carbonate group, a peroxy group, and a carboxylic anhydride group.

[0038] Examples of the alkoxy group include alkoxy groups having 1 to 4 carbon atoms, such as a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, and a tert-butoxy group.

[0039] Examples of aryloxy groups include aryloxy groups having an unsubstituted aryl group and aryloxy groups having 1 to 3 alkyl groups having 1 to 4 carbon atoms. Examples of the aryl group contained in the aryloxy group include a phenyl group. Specific examples include a phenoxy group, a 2,6-dimethylphenoxy group, a 2,4,6-trimethylphenoxy group, and a 3,5-di-tert-butylphenoxy group.

[0040] The ester group is a group containing an ester bond, and examples thereof include an acetyloxy group, a benzoyloxy group, a methoxycarbonyl group, a phenoxycarbonyl group, and a p-chlorophenoxycarbonyl group. Examples of the acyl group include a formyl group, an acetyl group, a benzoyl group, a p-chlorobenzoyl group, and a p-methoxybenzoyl group.

[0041] The nitrogen-containing group may be a group in which the nitrogen atom does not form a cyclic structure, such as an optionally substituted amide group, an optionally substituted amino group, an optionally substituted imino group, an optionally substituted imino group, a hydrazino group, a hydrazono group, a nitro group, a nitroso group, a cyano group, an isocyano group, a cyanate ester group, an amidino group, a diazo group, or an amino group in the form of an ammonium salt.

[0042] The amide group is a group containing an amide bond, and specific examples of the substituted amide group include acetamide, N-methylacetamide, and N-methylbenzamide.Specific examples of the substituted amino group include dimethylamino, ethylmethylamino, and diphenylamino.The imido group is a group having an imido bond, and specific examples of the substituted imido group include acetimide and benzimide.The imino group is a group having an imino bond, and specific examples of the substituted imino group include methylimino, ethylimino, propylimino, butylimino, and phenylimino.

[0043] Examples of sulfur-containing groups include alkylthio groups, arylthio groups, thioester groups, sulfone ester groups, optionally substituted sulfonamide groups, mercapto groups, dithioester groups, thioacyl groups, thioether groups, thiocyanate ester groups, isothiocyanate ester groups, thiocarboxyl groups, dithiocarboxyl groups, sulfo groups, sulfonyl groups, sulfinyl groups, and sulfenyl groups.

[0044] Specific examples of alkylthio groups include methylthio and ethylthio. Specific examples of arylthio groups include phenylthio, methylphenylthio, and naphthylthio. The thioester group is a group containing a thioester bond, and specific examples thereof include acetylthio, benzoylthio, methylthiocarbonyl, and phenylthiocarbonyl. Specific examples of sulfonate groups include methyl sulfonate, ethyl sulfonate, and phenyl sulfonate. The sulfonamide group is a group containing a sulfonamide bond, and specific examples of substituted sulfonamide groups include phenylsulfonamide, N-methylsulfonamide, and N-methyl-p-toluenesulfonamide.

[0045] Examples of heterocyclic compound residues include residues obtained from monocyclic or bicyclic polycyclic compounds having at least one heteroatom selected from a nitrogen atom, an oxygen atom, and a sulfur atom. Specific examples of heterocyclic compound residues include residues of 5- or 6-membered nitrogen-containing monocyclic compounds such as pyrrole, pyridine, pyrimidine, and triazine, residues of sulfur-containing bicyclic compounds such as quinoline, residues of 5- or 6-membered oxygen-containing monocyclic compounds such as furan and pyran, residues of sulfur-containing monocyclic compounds such as thiophene, and groups in which these heterocyclic compound residues are further substituted with one or more substituents such as alkyl groups and alkoxy groups having 1 to 30, preferably 1 to 20, carbon atoms.

[0046] Specific examples of boron-containing groups include boranediyl, boranetriyl, and diboranyl groups. Further examples include alkyl-substituted boron, aryl-substituted boron, boron halide, and alkyl-substituted boron halide groups. Examples of alkyl-substituted boron groups include (Et)B-, (iPr)B-, (iBu)B-, (Et)B, (iPr)B, and (iBu)B. Examples of aryl-substituted boron groups include (CH)B-, (CH)B, (CF)B, and (3,5-(CF)CH)B. Examples of boron halide groups include BCl- and BCl. Examples of alkyl-substituted boron halide groups include (Et)BCl-, (iBu)BCl-, and (CH)BCl. Here, Et represents an ethyl group, iPr represents an isopropyl group, and iBu represents an isobutyl group. Trisubstituted boron may be in a coordinate bond state.

[0047] Specific examples of aluminum-containing groups include alkyl-substituted aluminum, aryl-substituted aluminum, aluminum halide, and alkyl-substituted aluminum halide groups. Examples of alkyl-substituted aluminum groups include (Et)Al-, (iPr)Al-, (iBu)Al-, (Et)Al, (iPr)Al, and (iBu)Al. Examples of aryl-substituted aluminum groups include (C6H5)Al-. Examples of aluminum halide groups include AlCl2- and AlCl3. Examples of alkyl-substituted aluminum halide groups include (Et)AlCl- and (iBu)AlCl-. Here, Et represents an ethyl group, iPr represents an isopropyl group, and iBu represents an isobutyl group. Furthermore, tri-substituted aluminum may be in a coordinate bond state.

[0048] Examples of phosphorus-containing groups include phosphido groups, phosphoryl groups, thiophosphoryl groups, and phosphato groups.

[0049] Specific examples of silicon-containing groups include silyl groups, siloxy groups, hydrocarbon-substituted silyl groups, and hydrocarbon-substituted siloxy groups. Examples of hydrocarbon-substituted silyl groups include methylsilyl, dimethylsilyl, trimethylsilyl, ethylsilyl, diethylsilyl, triethylsilyl, diphenylmethylsilyl, triphenylsilyl, dimethylphenylsilyl, dimethyl-t-butylsilyl, and dimethyl(pentafluorophenyl)silyl. Among these, methylsilyl, dimethylsilyl, trimethylsilyl, ethylsilyl, diethylsilyl, triethylsilyl, dimethylphenylsilyl, and triphenylsilyl are preferred, and trimethylsilyl, triethylsilyl, triphenylsilyl, and dimethylphenylsilyl are more preferred. Examples of hydrocarbon-substituted siloxy groups include trimethylsiloxy.

[0050] Specific examples of the germanium-containing group and the tin-containing group include the silicon-containing groups exemplified above in which the silicon is substituted with germanium or tin.

[0051] Among the above substituents, a substituent other than a substituent containing a phosphorus atom or a nitrogen atom is more preferred, and a hydrocarbon group or an oxygen-containing substituent is even more preferred, and a hydrocarbon group is particularly preferred.

[0052] In general formula (1), R 1 ~R 4 Two or more of R may be linked to each other. 1 is R 3 and R 4 It is not connected to R 2 is R 3 and R 4 It is preferable that the amine compound is not linked to any of the specific groups. Preferred amine compounds not linked to any of the specific groups include, for example, the amine compounds of the three embodiments represented by the following general formulas (1A) to (1C).

[0053] [ka] (In general formula (1A), the definition of each group is the same as that of each group in general formula (1). However, R 1 ~R 4 is not linked to any group other than the nitrogen atom.

[0054] [ka] (In general formula (1B), the definition of each group is the same as that of each group in general formula (1). However, R 1 and R 2 is concatenated, and R 3 and R 4 are connected.)

[0055] [ka] (In general formula (1C), the definition of each group is the same as that of each group in general formula (1). However, R 1 and R 2 is not linked to any group other than the nitrogen, and R 3 and R 4 are connected.)

[0056] In general formula (1), R 1 ~R 4 may be a linear or branched group, or may be a group containing a cyclic structure, and R 1 ~R 4 Two or more of these may be linked together to form a ring structure. For example, R 1 and R 3 , R 2 and R 4 When either of them is linked (bonded), the number of bonds is preferably 4 or more, and R 1 and R 3 , R 2 and R 4 When both of the above are linked (bound), the number of bonds is preferably 3 or more.

[0057] The bond number refers to the number of bonds that connect one nitrogen atom to the other. For example, R 1 and R 3are both methylene groups (-CH2-) and are linked together, R 1 and R 3 The number of bonds in the link from one nitrogen atom to the other nitrogen atom, including

[0058] However, as represented by general formulas (1A) to (1C), R 1 is R 3 and R 4 It is not connected to R 2 is R 3 and R 4 It is preferable that R 1 ~R 4 Each of R preferably does not have a substituent with a cyclic structure, i.e., is a linear or branched group. 1 ~R 4 When R is a linear or branched group (for example, a linear or branched hydrocarbon group which may have a substituent), the number of carbon atoms in the linear or branched group is preferably 3 to 20, more preferably 3 to 15, and particularly preferably 3 to 10. 1 ~R 4 The total number of carbon atoms in R is preferably 8 or more. 1 ~R 4 is preferably linear.

[0059] R 1 ~R 4 When is any of the above preferred groups, the reaction activity of the olefin tends to be higher, and it tends to be easier to more efficiently produce α-olefins with relatively low boiling points, which are dimers to pentamers (preferably trimers to tetramers) of olefins. Here, when the raw material is ethylene, the trimers to tetramers correspond to hexene and octene. In other words, it tends to be suitable for producing olefins having 10 or less carbon atoms.

[0060] When the olefin multimerization catalyst containing the amine compound (B) of the present invention is used, the ratio of the amount of olefin multimers, i.e., olefin dimers to pentamers (preferably trimers to tetramers), produced to the total amount of products tends to be high. Specifically, this ratio is desirably 85% by weight or more, preferably 88% by weight or more, more preferably 90% by weight or more, and particularly preferably 91% by weight or more. Thus, for example, when the ratio of dimers to pentamers (preferably trimers to tetramers) produced is high, the number of types of multimers produced tends to be reduced. In addition, the difference in boiling points between the components is relatively large, making separation by distillation easy (for example, the boiling point of 1-hexene is 63°C, and the boiling point of 1-octene is 122 to 123°C). As a result, production costs can be reduced, and it is thought that it is easy to respond to market fluctuations.

[0061] On the other hand, R 1 and R 3 and have the same structure, and / or R 2 and R 4 It is also preferable that R 1 and R 3 is a linear propyl group, and R 2 and R 4 The amine compound (B-1) in which is a methyl group corresponds to this case.

[0062] R 1 and R 2 are linked to form a ring structure, and / or R 3 and R 4 When R are linked to form a ring structure, it is preferable that the two ring structures formed are the same. 1 ~R 4 It is often preferable that the structure with respect to is symmetrical or nearly symmetrical.

[0063] In addition, R 1 and R 2 If R is connected, and / or 3 and R 4 In the present invention, when R 1 and R 2The number of carbon atoms in each of (and / or R 3 and R 4 The number of carbon atoms in each of these is defined as the boundary at the point where half of the number of carbon atoms making up the linked structure is reached. If there is one carbon atom at this half point, the number of this carbon atom is set to "0.5" and R 1 and R 2 The number of carbon atoms in each of (and / or R 3 and R 4 For example, R 1 and R 2 When R is linked to the nitrogen atom to form a piperidin-1-yl group, 1 and R 2 The number of carbon atoms in each of these is 2.5.

[0064] One nitrogen atom is R 1 and R 2 The structure formed with the other nitrogen atom is R 3 and R 4 It is not entirely clear why a better effect is obtained when the structure formed with R is the same. 1 ~R 4 is considered to be located relatively close to the chromium atom of the central metal, chromium compound (A), so R in the above structure 1 ~R 4 It is speculated that the steric influence of the ethylene coordination to the metallacycle and the activation energy of the insertion reaction may be appropriately controlled.

[0065] Furthermore, in each of the preferred embodiments described above, not only is the production efficiency of ethylene trimers (1-hexene) and tetramers (1-octene) high, but it is also preferable in terms of the reactivity of ethylene and the efficient production of 1-octene.

[0066] When ethylene polymers are produced in the present invention, 1-hexene and 1-octene are the main products. These products can be separated relatively easily by distillation. Therefore, the production efficiency of 1-octene described above is considered to be an important indicator from an industrial viewpoint. In particular, this may be an important factor when using a production facility for co-producing 1-hexene and 1-octene.

[0067] Specific examples of the amine compound (B) are shown below, but the amine compound (B) is not limited to these.

[0068] [ka]

[0069] [ka]

[0070] In the above compounds, Me is a methyl group, Et is an ethyl group, n Pr is a normal propyl group, i Pr represents an isopropyl group, and Ph represents a phenyl group. The number of carbon atoms between N and N in each of the above compounds is 1 or 2, but compounds in which the number of carbon atoms between N and N is changed to 3 or more can also be used.

[0071] A commercially available amine compound may be used as the amine compound (B). When synthesizing the amine compound (B), for example, the amine compound (B) can be obtained by alkylating or arylating a specific amine compound by a general method. The amine compound (B) can also be obtained by reducing an imine compound by a general method. In the present invention, multiple types of amine compounds (B) can also be used in combination.

[0072] As explained above, when the olefin oligomerization catalyst containing the amine compound (B) of the present invention is used, 1-octene tends to be produced efficiently.

[0073] The amine compound (B) and the chromium compound (A) may be added separately to the reactor. However, it is preferable to add a transition metal complex formed in advance by reacting the amine compound (B) with the chromium compound (A) to the reactor. For example, the transition metal complex can be obtained by dissolving the amine compound (B) in a solvent, mixing it with the chromium compound (A), and stirring the mixture under an inert gas atmosphere such as nitrogen or argon at a temperature of −78° C. to room temperature or under reflux for about 5 minutes to 48 hours.

[0074] The solvent used in synthesizing the transition metal complex is not particularly limited. Any common solvent known to be usable in such reactions can be used. Specific examples of the solvent include polar solvents such as ether and tetrahydrofuran; hydrocarbon solvents such as toluene, methylcyclohexane, and heptane; and halogenated hydrocarbon solvents such as methylene chloride.

[0075] The transition metal complex is obtained in a state of being dissolved or suspended in a solvent. This solution or suspension of the transition metal complex may be used as is, or the transition metal complex may be isolated and then dissolved or suspended again in a solvent before use.

[0076] <Organometallic compound (C)> The organometallic compound serving as component (C) (hereinafter also referred to as "compound (C)") is a compound specified by the following general formula (2).

[0077] [ka]

[0078] (In general formula (2), I C + is a cation containing an atom from Group 14 or 15 of the periodic table, IA is an atom selected from group 13 elements of the periodic table, R α is a substituent containing a hydrogen atom or an atom selected from the group consisting of atoms in groups 14 to 17 of the periodic table, R his a halogen-containing hydrocarbon group, m is a positive real number, n is 0 or a positive real number, and 2 < m ≦ 4 and m + n = 4 are satisfied.)

[0079] The above IC + As specific examples, the same substances as the cations of the component (C-3) described later can be exemplified. Preferably, tertiary carbonium cations and aromatic aminocations can be mentioned. More specifically, triarylmethyl cations typified by trityl cation and arylanilinium cation can be mentioned.

[0080] As the above IA, an aluminum atom is particularly preferable. The above R α Specifically, the same compounds as the above R 1 ~R 4 can be exemplified. The above R h is preferably a halogen-containing aliphatic hydrocarbon or a halogen-containing alicyclic hydrocarbon. As the above halogen, fluorine is particularly preferable. Further, the fluorine is preferably contained in the structure of a trifluoromethyl group. Specific examples of the compound (C) are shown below.

[0081]

Chemical formula

[0082] When the above compound (C) is used and the oligomerization reaction of an olefin described later is carried out, the by-production of an olefin polymer can often be suppressed without impairing the activity. Therefore, when industrially producing an olefin oligomer, it can be expected that an olefin polymer adheres to the inner walls and surfaces such as the reaction apparatus, heat exchanger, and inner walls, making it difficult for heat conduction to decrease and for piping to become blocked.

[0083] The reason why the above compound (C) exhibits such an effect is not yet known at present, but the present inventors have the following hypothesis in mind.

[0084] Olefin polymerization reactions such as those of the present invention are believed to proceed via a metallacycle mechanism. In this mechanism, component (A) (which is believed to function as a cation during the reaction) and component (C) (which is believed to function as an anion during the reaction) are not in a state of ion separation but are thought to have some kind of interaction. Therefore, the reduction reaction (which produces olefin polymers such as hexene and octene) and the polymerization reaction (which produces polyolefins) are in a competitive state. Furthermore, in this mechanism, the reduction reaction is thought to be more dominant when the electron density of the cation of component (A) is lower.

[0085] Since the component (C) of the present invention is a relatively large molecule, it maintains a moderate distance from the component (A), making it difficult for electrons to be donated to the component (A), which may result in a tendency for the electron density of the component (A) to be low. h It is thought that because the compound has a structure that requires an electron-withdrawing atom such as a halogen, it is difficult for electrons to be donated to component (A). For this reason, it is thought that the ethylene polymerization reaction is relatively difficult to occur, that is, the olefin oligomerization reaction is dominant.

[0086] In the present invention, other organometallic compounds can be used in combination with the compound (C). Such compounds include at least one compound selected from the group consisting of an organometallic compound as component (C-1) (hereinafter also referred to as "organometallic compound (C-1)"), an organoaluminum oxy compound as component (C-2) (hereinafter also referred to as "organoaluminum oxy compound (C-2)"), and a compound as component (C-3) (hereinafter also referred to as "compound (C-3)" or "ionizing ionic compound (C-3)") that reacts with a transition metal compound to form an ion pair. These components (C-1) to (C-3) are described below.

[0087] [Organometallic compound (C-1)] As the organometallic compound (C-1), for example, organometallic compounds of Groups 1, 2, 12, and 13 of the periodic table such as the compounds (C-1a), (C-1b), and (C-1c) described below can be used. In the present invention, the organometallic compound (C-1) is assumed not to include the organoaluminum oxy compound (C-2) described later.

[0088] (C-1a): General formula R a m Al(OR b ) n H p X q (In the formula, R a and R b each independently represent a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms, X represents a halogen atom, m is a number where 0 < m ≦ 3, n is a number where 0 ≦ n < 3, p is a number where 0 ≦ p < 3, q is a number where 0 ≦ q < 3, and m + n + p + q = 3) represents an organoaluminum compound.

[0089] (C-1b): General formula M 2 AlR a 4 (In the formula, M 2 represents Li, Na, or K, and R a represents a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms) represents a complex alkyl compound of a Group 1 metal of the periodic table and aluminum.

[0090] (C-1c): General formula R a R b M 3 (In the formula, R a and R b each independently represent a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms, and M 3 is Mg, Zn, or Cd) represents a dialkyl compound of a Group 2 or 12 metal of the periodic table.

[0091] As the organoaluminum compound (C-1a), for example, General formula R a m Al(OR b ) 3-m(wherein R a and R b each independently represent a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms, and m is preferably a number satisfying 1.5 ≦ m ≦ 3.) An organoaluminum compound represented by General formula R a m AlX 3-m (wherein R a represents a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms, X represents a halogen atom, and m is preferably a number satisfying 0 < m < 3.) An organoaluminum compound represented by General formula R a m AlH 3-m (wherein R a represents a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms, and m is preferably a number satisfying 2 ≦ m < 3) An organoaluminum compound represented by General formula R a m Al(OR b ) n X q (wherein R a and R b each independently represent a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms, X represents a halogen atom, m is 0 < m ≦ 3, n is 0 ≦ n < 3, q is 0 ≦ q < 3, and m + n + q = 3) An organoaluminum compound represented by can be used.

[0092] Specific examples of the organoaluminum compound (C-1a) include tri(n-alkyl)aluminums such as trimethylaluminum, triethylaluminum, tri(n-butyl)aluminum, tripropylaluminum, tripentylaluminum, trihexylaluminum, trioctylaluminum, and tridecylaluminum; tribranched-chain alkylaluminums such as triisopropylaluminum, triisobutylaluminum, tri(sec-butyl)aluminum, tri(tert-butyl)aluminum, tri(2-methylbutyl)aluminum, tri(3-methylbutyl)aluminum, tri(2-methylpentyl)aluminum, tri(3-methylpentyl)aluminum, tri(4-methylpentyl)aluminum, tri(2-methylhexyl)aluminum, tri(3-methylhexyl)aluminum, and tri(2-ethylhexyl)aluminum; tricycloalkylaluminums such as tricyclohexylaluminum and tricyclooctylaluminum; triarylaluminums such as triphenylaluminum and tritolylaluminum; dialkylaluminum hydrides such as diethylaluminum hydride and diisobutylaluminum hydride; (iCH) x Al y (C5H 10 ) z (wherein x, y, and z are positive numbers, and z≧2x. iC4H9 represents an isobutyl group); alkylaluminum alkoxides such as isobutylaluminum methoxide, isobutylaluminum ethoxide, and isobutylaluminum isopropoxide; dialkylaluminum alkoxides such as dimethylaluminum methoxide, diethylaluminum ethoxide, and dibutylaluminum butoxide; alkylaluminum sesquialkoxides such as ethylaluminum sesquiethoxide and butylaluminum sesquibutoxide; a 2.5 Al(OR b ) 0.5 (In the formula, R a and R band each represent a hydrocarbon group having 1 to 15, preferably 1 to 4, carbon atoms, which may be the same or different. Partially alkoxylated alkylaluminums having an average composition represented by the formula (I) above; dialkylaluminum aryloxides such as diethylaluminum phenoxide, diethylaluminum (2,6-di-t-butyl-4-methylphenoxide), ethylaluminum bis(2,6-di-t-butyl-4-methylphenoxide), diisobutylaluminum (2,6-di-t-butyl-4-methylphenoxide), and isobutylaluminum bis(2,6-di-t-butyl-4-methylphenoxide); dialkylaluminum halides such as dimethylaluminum chloride, diethylaluminum chloride, dibutylaluminum chloride, diethylaluminum bromide, and diisobutylaluminum chloride; ethylaluminum sesquichloride, butylaluminum sesquichloride, and the like. partially halogenated alkylaluminums such as alkylaluminum dihalides such as ethylaluminum dichloride, propylaluminum dichloride, and butylaluminum dibromide; dialkylaluminum hydrides such as diethylaluminum hydride and dibutylaluminum hydride; partially hydrogenated alkylaluminums such as alkylaluminum dihydrides such as ethylaluminum dihydride and propylaluminum dihydride; and partially alkoxylated and halogenated alkylaluminums such as ethylaluminum ethoxychloride, butylaluminum butoxychloride, and ethylaluminum ethoxybromide.

[0093] Compounds similar to the organoaluminum compound (C-1a), for example, organoaluminum compounds in which two or more aluminum compounds are bonded via nitrogen atoms, such as (C2H5)2AlN(C2H5)Al(C2H5)2, can also be used.

[0094] Specific examples of the compound (C-1b) include LiAl(C2H5)4, LiAl(C7H 15 )4 can be mentioned.

[0095] Specific examples of the compound (C-1c) include dimethyl magnesium, diethyl magnesium, dibutyl magnesium, and butylethyl magnesium.

[0096] Specific examples of the organometallic compound (C-1) other than the compounds (C-1a) to (C-1c) explained above include methyllithium, ethyllithium, propyllithium, butyllithium, methylmagnesium bromide, methylmagnesium chloride, ethylmagnesium bromide, ethylmagnesium chloride, propylmagnesium bromide, propylmagnesium chloride, butylmagnesium bromide, and butylmagnesium chloride.

[0097] It is also possible to use a compound that forms an organoaluminum compound in the polymerization reaction system, such as a combination of an aluminum halide and an alkyllithium, or a combination of an aluminum halide and an alkylmagnesium.

[0098] The organometallic compounds (C-1) described above can be used singly or in combination of two or more. Among the organometallic compounds (C-1) described above, the organoaluminum compounds (C-1a) are particularly preferred.

[0099] [Organoaluminum oxy compound (C-2)] The organoaluminum oxy compound (C-2) may be a conventionally known aluminoxane, or may be a benzene-insoluble organoaluminum oxy compound such as those exemplified in JP-A-2-78687. Conventionally known aluminoxanes can be produced, for example, by the following method, and are usually obtained as a solution.

[0100] (1) A method in which an organoaluminum compound such as trialkylaluminum is added to a suspension containing a compound containing adsorbed water or a salt containing water of crystallization (e.g., magnesium chloride hydrate, copper sulfate hydrate, aluminum sulfate hydrate, nickel sulfate hydrate, cerous chloride hydrate) and a hydrocarbon solvent, and the adsorbed water or water of crystallization is reacted with the organoaluminum compound.

[0101] (2) A method in which water, ice or water vapor is directly reacted with an organoaluminum compound such as trialkylaluminum in a solvent such as benzene, toluene, ethyl ether or tetrahydrofuran.

[0102] (3) A method in which an organoaluminum compound such as trialkylaluminum is reacted with an organotin oxide such as dimethyltin oxide or dibutyltin oxide in a solvent such as decane, benzene, or toluene.

[0103] The aluminoxane may contain a small amount of an organometallic component. The solvent and unreacted organoaluminum compound may be distilled off from the aluminoxane solution recovered in each of the above methods, and the resulting aluminoxane may be redissolved in a solvent or suspended in a poor solvent for the aluminoxane.

[0104] Specific examples of organoaluminum compounds used for producing aluminoxanes are the same as those of the organoaluminum compound (C-1a) described above. The organoaluminum compounds can be used alone or in combination of two or more. Among them, trialkylaluminum and tricycloalkylaluminum are preferred, and trimethylaluminum is particularly preferred.

[0105] Examples of solvents that can be used for producing aluminoxane include hydrocarbon solvents and ether solvents. Specific examples of hydrocarbon solvents include aromatic hydrocarbons such as benzene, toluene, xylene, cumene, and cymene; aliphatic hydrocarbons such as pentane, hexane, heptane, octane, decane, dodecane, hexadecane, and octadecane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, cyclooctane, and methylcyclopentane; petroleum fractions such as gasoline, kerosene, and diesel; and aromatic, aliphatic, or alicyclic hydrocarbon halides (especially chlorinated or brominated compounds). Specific examples of ether solvents include ethyl ether and tetrahydrofuran. Among these, aromatic hydrocarbons and aliphatic hydrocarbons are preferred. When using an organoaluminum oxy-compound that is insoluble or poorly soluble in benzene, the amount of Al component dissolved in benzene at 60°C is typically 10% or less, preferably 5% or less, and more preferably 2% or less, calculated as Al atoms.

[0106] As the organoaluminum oxy compound (C-2), a boron-containing organoaluminum oxy compound represented by the following general formula (5) can also be used.

[0107] [ka]

[0108] (In general formula (5), R 7 R represents a hydrocarbon group having 1 to 10 carbon atoms or a halogenated hydrocarbon group having 1 to 10 carbon atoms. 8 are the same or different and represent a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 10 carbon atoms.

[0109] The boron-containing organoaluminum oxy compound represented by general formula (5) can be produced, for example, by reacting an alkylboronic acid represented by the following general formula (6) with an organoaluminum compound in an inert solvent under an inert gas atmosphere at a temperature of −80° C. to room temperature for 1 minute to 24 hours.

[0110] R 7 -B(OH)2 (6) (In general formula (6), R 7 is R in the above general formula (5) 7 )

[0111] Specific examples of alkylboronic acids represented by general formula (6) include methylboronic acid, ethylboronic acid, isopropylboronic acid, n-propylboronic acid, n-butylboronic acid, isobutylboronic acid, n-hexylboronic acid, cyclohexylboronic acid, phenylboronic acid, 3,5-difluorophenylboronic acid, pentafluorophenylboronic acid, and 3,5-bis(trifluoromethyl)phenylboronic acid. Among these, methylboronic acid, n-butylboronic acid, isobutylboronic acid, 3,5-difluorophenylboronic acid, and pentafluorophenylboronic acid are preferred. These alkylboronic acids can be used alone or in combination of two or more.

[0112] Specific examples of the organoaluminum compound to be reacted with alkylboronic acid are the same as those of the organoaluminum compound (C-1a) described above. The organoaluminum compound can be used alone or in combination of two or more. Among them, trialkylaluminum and tricycloalkylaluminum are preferred, and trimethylaluminum, triethylaluminum, and triisobutylaluminum are more preferred.

[0113] The organoaluminum oxy compounds (C-2) explained above can be used singly or in combination of two or more.

[0114] [Ionized ionic compounds (C-3)] The ionizing ionic compound (C-3) is a compound that reacts with a transition metal compound to form an ion pair. Therefore, at least any compound that has the property of forming an ion pair when contacted with a transition metal compound corresponds to this ionizing ionic compound (C-3).

[0115] Examples of the ionizable ionic compound (C-3) that can be used include Lewis acids, ionic compounds, borane compounds, and carborane compounds described in JP-T-1-501950, JP-T-1-502036, JP-A-3-179005, JP-A-3-179006, JP-A-3-207703, JP-A-3-207704, and U.S. Patent No. 5,321,106. Heteropoly compounds and isopoly compounds can also be used.

[0116] Examples of the Lewis acid include compounds represented by the general formula BR3 (R is fluorine, or a phenyl group which may have a substituent such as fluorine, a methyl group, or a trifluoromethyl group). Specific examples thereof include trifluoroboron, triphenylboron, tris(4-fluorophenyl)boron, tris(3,5-difluorophenyl)boron, tris(4-fluoromethylphenyl)boron, tris(pentafluorophenyl)boron, tris(p-tolyl)boron, tris(o-tolyl)boron, and tris(3,5-dimethylphenyl)boron.

[0117] Specific examples of the ionic compound include compounds represented by the following general formula (7).

[0118] [ka]

[0119] In general formula (7), R 9+ For example, H + , carbonium cation, oxonium cation, ammonium cation, phosphonium cation, cycloheptyltrienyl cation, and ferrocenium cation containing a transition metal. 10 ~R 13 are organic groups which may be the same or different, preferably aryl groups or substituted aryl groups.

[0120] R 9+Specific examples of when is a carbonium cation include trisubstituted carbonium cations such as triphenylcarbonium cation, tri(methylphenyl)carbonium cation, and tri(dimethylphenyl)carbonium cation.

[0121] R 9+ Specific examples of when is an ammonium cation include trialkylammonium cations such as trimethylammonium cation, triethylammonium cation, tri(n-propyl)ammonium cation, and tri(n-butyl)ammonium cation; N,N-dialkylanilinium cations such as N,N-dimethylanilinium cation, N,N-diethylanilinium cation, and N,N,2,4,6-pentamethylanilinium cation; and dialkylammonium cations such as di(isopropyl)ammonium cation and dicyclohexylammonium cation.

[0122] R 9+ Specific examples of when is a phosphonium cation include triarylphosphonium cations such as triphenylphosphonium cation, tri(methylphenyl)phosphonium cation, and tri(dimethylphenyl)phosphonium cation.

[0123] R 9+ As the cation, a carbonium cation or an ammonium cation is preferred, and a triphenylcarbonium cation, an N,N-dimethylanilinium cation or an N,N-diethylanilinium cation is more preferred.

[0124] In addition to the compound represented by the general formula (7) explained above, the ionic compound may also be a trialkyl-substituted ammonium salt, an N,N-dialkylanilinium salt, a dialkylammonium salt, or a triarylphosphonium salt.

[0125] Specific examples of the trialkyl-substituted ammonium salt include triethylammonium tetraphenylborate, tri(n-propyl)ammonium tetraphenylborate, tri(n-butyl)ammonium tetraphenylborate, trimethylammonium tetra(p-tolyl)borate, trimethylammonium tetra(o-tolyl)borate, tri(n-butyl)ammonium tetra(pentafluorophenyl)borate, tri(n-propyl)ammonium tetra(o,p-dimethylphenyl)borate, tri(n-butyl)ammonium tetra(m,m-dimethylphenyl)borate, tri(n-butyl)ammonium tetra(p-trifluoromethylphenyl)borate, tri(n-butyl)ammonium tetra(3,5-ditrifluoromethylphenyl)borate, and tri(n-butyl)ammonium tetra(o-tolyl)borate.

[0126] Specific examples of the N,N-dialkylanilinium salt include N,N-dimethylanilinium tetraphenylborate, N,N-diethylanilinium tetraphenylborate, and N,N,2,4,6-pentamethylanilinium tetraphenylborate.

[0127] Specific examples of the dialkylammonium salt include di(n-propyl)ammonium tetra(pentafluorophenyl)borate and dicyclohexylammonium tetraphenylborate.

[0128] In addition to the salts described above, the ionic compound may also be triphenylcarbenium tetrakis(pentafluorophenyl)borate, N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate, ferrocenium tetra(pentafluorophenyl)borate, triphenylcarbenium pentaphenylcyclopentadienyl complex, N,N-diethylanilinium pentaphenylcyclopentadienyl complex, or a boron compound represented by the following general formula (8) or (9):

[0129] [ka] (In the general formula (8), Et represents an ethyl group.)

[0130] [ka] (In the general formula (9), Et represents an ethyl group.)

[0131] Specific examples of the borane compound include decaborane (14); salts of anions such as bis[tri(n-butyl)ammonium]nonaborate, bis[tri(n-butyl)ammonium]decaborate, bis[tri(n-butyl)ammonium]undecaborate, bis[tri(n-butyl)ammonium]dodecaborate, bis[tri(n-butyl)ammonium]decachlorodecaborate, and bis[tri(n-butyl)ammonium]dodecachlorododecaborate; and salts of metal borane anions such as tri(n-butyl)ammonium bis(dodecahydridedodecaborate)cobaltate(III) and bis[tri(n-butyl)ammonium]bis(dodecahydridedodecaborate)nickelate(III).

[0132] Specific examples of the carborane compound include 4-carbanonaborane (14), 1,3-dicarbanonaborane (13), 6,9-dicarbadecaborane (14), dodecahydride-1-phenyl-1,3-dicarbanonaborane, dodecahydride-1-methyl-1,3-dicarbanonaborane, undecahydride-1,3-dimethyl-1,3-dicarbanonaborane, 7,8-dicarbaundecaborane (13), 2,7-dicarbaundecaborane (13), undecahydride-7,8-dimethyl- 7,8-Dicarbaundecaborane, Dodecahydride-11-methyl-2,7-dicarbaundecaborane, Tri(n-butyl)ammonium 1-carbadecaborate, Tri(n-butyl)ammonium 1-carbaundecaborate, Tri(n-butyl)ammonium 1-carbadodecaborate, Tri(n-butyl)ammonium 1-trimethylsilyl-1-carbadecaborate, Tri(n-butyl)ammonium bromo-1-carbadodecaborate, Tri(n-butyl)ammonium 6-carbadecaborate late (14), tri(n-butyl)ammonium 6-carbadecaborate (12), tri(n-butyl)ammonium 7-carbaundecaborate (13), tri(n-butyl)ammonium 7,8-dicarbaundecaborate (12), tri(n-butyl)ammonium 2,9-dicarbaundecaborate (12), tri(n-butyl)ammonium dodecahydride-8-methyl-7,9-dicarbaundecaborate, tri(n-butyl)ammonium undecahydride-8-ethyl-7 Salts of anions such as ,9-dicarboxamyl-7,9-dicarboxamyl-4,6-dibromo-7-carbaundecaborate, tri(n-butyl)ammonium undecahydride-8-butyl-7,9-dicarboxamyl-4,6-dibromo-7-carbaundecaborate, tri(n-butyl)ammonium undecahydride-8-allyl-7,9-dicarboxamyl-4,6-dibromo-7-carbaundecaborate, tri(n-butyl)ammonium undecahydride-9-trimethylsilyl-7,8-dicarboxamyl-4,6-dibromo-7-carbaundecaborate;Tri(n-butyl)ammonium bis(nonahydride-1,3-dicarbanonaborate)cobaltate(III), tri(n-butyl)ammonium bis(undecahydride-7,8-dicarbanonaborate)ferrate(III), tri(n-butyl)ammonium bis(undecahydride-7,8-dicarbandecaborate)cobaltate(III), tri(n-butyl)ammonium bis(undecahydride-7,8-dicarbandecaborate)nickelate(III), tri(n-butyl)ammonium bis(undecahydride-7,8-dicarbandecaborate)cuprate(III), tri(n-butyl)ammonium bis(undecahydride-7,8-dicarbandecaborate)aurate(III), tri(n-butyl)ammonium bis(nonahydride-7,8-dimethyl-7,8-dicarbandecaborate)iron Salts of metal carborane anions such as tri(n-butyl)ammonium bis(undecahydride-7,8-dimethyl-7,8-dicarboxamdecaborate)chromate(III), tri(n-butyl)ammonium bis(tribromooctahydride-7,8-dicarboxamdecaborate)cobaltate(III), tris[tri(n-butyl)ammonium]bis(undecahydride-7-carbaundecaborate)chromate(III), bis[tri(n-butyl)ammonium]bis(undecahydride-7-carbaundecaborate)manganate(IV), bis[tri(n-butyl)ammonium]bis(undecahydride-7-carbaundecaborate)cobaltate(III), and bis[tri(n-butyl)ammonium]bis(undecahydride-7-carbaundecaborate)nickelate(IV);

[0133] The heteropoly compound typically comprises atoms of silicon, phosphorus, titanium, germanium, arsenic, or tin, and one or more atoms selected from vanadium, niobium, molybdenum, and tungsten. Specific examples include phosphovanadic acid, germanovanadic acid, arsenic vanadic acid, phosphoniobic acid, germanoniobic acid, siliconomolybdic acid, phosphomolybdic acid, titaniummolybdic acid, germanomolybdic acid, arsenic molybdic acid, tinmolybdic acid, phosphotungstic acid, germanotungstic acid, tintungstic acid, phosphomolybdovanadic acid, phosphotungstovanadic acid, germanotungstovanadic acid, phosphomolybdotungstovanadic acid, germanomolybdotungstovanadic acid, phosphomolybdotungstic acid, and phosphomolybdoniobic acid. The compound may also be a salt of each of these acids. Specific examples of salts include salts with metals of Group 1 or 2 of the periodic table (e.g., lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, and barium), organic salts such as triphenylethyl salts, and isopoly compounds.

[0134] The ionized ionic compounds (C-3) explained above can be used singly or in combination of two or more.

[0135] The use of the above olefin polymerization catalysts allows for the production of olefin polymers with high activity, and when ethylene is used as the olefin, the selectivity to 1-octene is particularly high. For example, the use of an organoaluminum oxy compound (C-2) such as methylaluminoxane as a cocatalyst component in combination with the catalyst exhibits higher activity toward ethylene, enabling the production of 1-octene. Furthermore, the use of an ionizing ionic compound (C-3) such as triphenylcarbonium tetrakis(pentafluorophenyl)borate as a cocatalyst component also allows for the production of 1-octene from ethylene with better activity and higher selectivity.

[0136] In the present invention, the compound (C) is preferably an organoaluminum oxy compound (C-2), and particularly preferably methylaluminoxane.

[0137] <Carrier (D)> The olefin polymerization catalyst of the present invention may contain a support (D). The support (D) is an inorganic or organic compound, and is usually a granular or particulate solid. The support (D) is used to support each component, such as the chromium compound (A), the amine compound (B), and the compound (C). As the inorganic compound, porous oxides, inorganic halides, clays, clay minerals, and ion-exchangeable layered compounds are preferred.

[0138] Specific examples of the porous oxide include SiO2, Al2O3, MgO, ZrO, TiO2, BO3, CaO, ZnO, BaO, ThO2, and composites or mixtures containing these (e.g., natural or synthetic zeolites, SiO2-MgO, SiO2-Al2O3, SiO2-TiO2, SiO2-VO5, SiO2-Cr2O3, SiO2-TiO2-MgO). Among these, porous oxides primarily composed of SiO2 and / or Al2O3 are preferred. The porous oxide may contain small amounts of carbonates, sulfates, nitrates, or oxides such as Na2CO3, K2CO3, CaCO3, MgCO3, Na2SO4, Al2(SO4)3, BaSO4, KNO3, Mg(NO3)2, Al(NO3)3, Na2O, KO, and Li2O. The particle size, specific surface area, and pore volume of the porous oxide are not particularly limited and may be appropriately determined depending on the type of material and the manufacturing method. In the present invention, the particle size of the porous oxide is preferably 0.5 to 300 μm, more preferably 20 to 200 μm, and the specific surface area is preferably 50 to 1000 m. 2 / g, more preferably 100 to 700m 2 / g, and the pore volume is preferably 0.3 to 3.0 cm 3 The porous oxide is preferably fired at 100 to 1000°C, more preferably 150 to 700°C, as needed.

[0139] Specific examples of the inorganic halide include MgCl, MgBr, MnCl, and MnBr. The inorganic halide may be used as is, or may be used after being pulverized using a ball mill or a vibration mill. Alternatively, the inorganic halide may be dissolved in a solvent such as alcohol and then precipitated into fine particles using a precipitating agent.

[0140] The clay typically contains a clay mineral as its main component. The ion-exchangeable layered compound is a compound with a crystalline structure in which planes formed by ionic bonds are stacked parallel to each other with weak bonding forces, and the ions contained therein are exchangeable. Examples of ion-exchangeable layered compounds that can be used include ionic crystalline compounds with layered crystalline structures such as hexagonal close packing, antimony, CdCl2, and CdI2. Most clay minerals are ion-exchangeable layered compounds. These clays, clay minerals, and ion-exchangeable layered compounds can be natural or synthetic.

[0141] Examples of clays and clay minerals include kaolin, bentonite, kibushi clay, gairome clay, allophane, hisingerite, pyrophyllite, mica, montmorillonite, vermiculite, hectorite, taeniolite, ryokudeite, palygorskite, kaolinite, nacrite, dickite, and halloysite. Examples of ion-exchange layered compounds include crystalline acid salts of polyvalent metals such as α-Zr(HAsO4)2·H2O, α-Zr(KPO4)2·3H2O, α-Ti(HPO4)2, α-Ti(HAsO4)2·H2O, α-Sn(HPO4)2·H2O, γ-Zr(HPO4)2, γ-Ti(HPO4)2, and γ-Ti(NH4PO4)2·H2O. Among these, clay and clay minerals are preferred, and synthetic mica, montmorillonite, vermiculite, hectorite, and taeniolite are more preferred.

[0142] The pore volume of the clay, clay mineral, and ion-exchangeable layered compound is preferably 0.1 cc / g or more, more preferably 0.3 to 5 cc / g. This pore volume is determined by mercury intrusion porosimetry using a mercury porosimeter, using a pore radius of 20 to 3 × 10 4 When a carrier having a pore volume of less than 0.1 cc / g with a radius of 20 angstroms or more is used, it tends to be difficult to obtain high polymerization activity.

[0143] It is also preferable to subject clay and clay minerals to chemical treatment. Examples of chemical treatment include surface treatment to remove impurities attached to the surface and treatment to affect the crystalline structure of the clay. Specific examples of chemical treatment include acid treatment, alkali treatment, salt treatment, and organic treatment. Acid treatment not only removes surface impurities but also increases the surface area by eluting cations such as Al, Fe, and Mg in the crystalline structure. Alkaline treatment destroys the crystalline structure of the clay and changes its structure. Salt treatment and organic treatment can change the surface area and interlayer distance by forming ionic complexes, molecular complexes, or organic derivatives.

[0144] The ion-exchangeable layered compound may be a layered compound in which the interlayer spacing has been expanded by exchanging the exchangeable ions between the layers with other large, bulky ions. These bulky ions act as supports supporting the layered structure and are usually called pillars. The introduction of another substance between the layers of a layered compound in this way is called intercalation. Specific examples of guest compounds (other substances) to be intercalated include cationic inorganic compounds such as TiCl4 and ZrCl4, metal alkoxides such as Ti(OR)4, Zr(OR)4, PO(OR)3, and B(OR)3 (where R is a hydrocarbon group, etc.), and [Al 13 O4(OH) 24 ] 7+ , [Zr(OH) 14 ] 2+ , [Fe3O(OCOCH3)6] +Examples of suitable guest compounds include metal hydroxide ions such as those mentioned above. Guest compounds can be used singly or in combination of two or more. When intercalating a guest compound, it is also possible to allow the coexistence of a dimer obtained by hydrolysis of a metal alkoxide (where R is a hydrocarbon group, for example) such as Si(OR)4, Al(OR)3, or Ge(OR)4, or a colloidal inorganic compound such as SiO2. Specific examples of pillars include oxides produced by intercalating the above metal hydroxide ions between layers and then dehydrating them with heat.

[0145] The clay, clay mineral, and ion-exchangeable layered compound may be used as is, or may be used after treatment such as ball milling or sieving, or may be used after adding fresh water to adsorb it, or may be used after heat dehydration treatment.

[0146] Examples of the organic compound include granular or fine particle solid organic compounds with particle sizes of 10 to 300 μm. Specific examples of polymer monomers constituting the organic compound include (co)dimers formed mainly from α-olefins having 2 to 14 carbon atoms, such as ethylene, propylene, 1-butene, and 4-methyl-1-pentene, (co)dimers formed mainly from vinylcyclohexane and styrene, and modified products thereof.

[0147] <Organic compound component (E)> The olefin polymerization catalyst of the present invention may further contain an organic compound as component (E) as required.

[0148] In the present invention, the organic compound as component (E) (hereinafter also referred to as "organic compound (E)") is used, for example, for the purpose of improving the polymerizability. Examples of such organic compounds that can be used include alcohols, phenolic compounds, carboxylic acids, phosphorus compounds, and sulfonates. However, component (E) is not limited to these.

[0149] The alcohols and phenolic compounds are generally selected from the group consisting of R14 Compounds represented by -OH are used. 14 represents a hydrocarbon group having 1 to 50 carbon atoms or a halogenated hydrocarbon group having 1 to 50 carbon atoms. 14 is a halogenated hydrocarbon. As the phenolic compound, a compound in which the α,α'-positions of the hydroxyl group are substituted with a hydrocarbon having 1 to 20 carbon atoms is preferred.

[0150] The carboxylic acid is usually R 15 The compound represented by -COOH is used. 15 represents a hydrocarbon group having 1 to 50 carbon atoms or a halogenated hydrocarbon group having 1 to 50 carbon atoms. In particular, R 15 is a halogenated hydrocarbon group having 1 to 50 carbon atoms.

[0151] The phosphorus compound is preferably a phosphoric acid having a P-O-H bond, or a phosphate or phosphine oxide compound having a P-O-R bond or a P=O bond.

[0152] As the sulfonate, for example, a compound represented by the following general formula (10) can be used.

[0153] [ka]

[0154] In general formula (10), M 2 is an element in groups 1 to 14 of the periodic table, and R 14 is hydrogen, a hydrocarbon group having 1 to 20 carbon atoms, or a halogenated hydrocarbon group having 1 to 20 carbon atoms; Z is a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, or a halogenated hydrocarbon group having 1 to 20 carbon atoms; t is an integer of 1 to 7; u is an integer that satisfies 1≦u≦7 and tu≧1.

[0155] <Halogen-containing aryl compounds containing one or two hydroxyl groups per molecule> The olefin polymerization catalyst of the present invention may also contain a halogen-containing aryl compound containing one or two hydroxyl groups per molecule selected from the above organic compounds (E) as an essential component (F) to be combined with components (A), (B), and (C). Among such compounds, halogen-containing phenolic compounds are preferred. Examples of such halogen-containing phenolic compounds include the following fluorine-containing phenolic compounds.

[0156] As the fluorine-containing phenol compound containing one hydroxyl group in one molecule, a compound represented by the following general formula (11) is preferred.

[0157] [ka] (In general formula (11), n ​​represents 0 or 1, and when n=0, m represents 1, and when n=1, m represents 3. x represents an integer of 1 to 5.)

[0158] Specific examples of the compound of general formula (11) include 2-fluorophenol, 3-fluorophenol, 4-fluorophenol, 2,3-difluorophenol, 2,5-difluorophenol, 2,4-difluorophenol, 2,6-difluorophenol, 3,4-difluorophenol, 3,5-difluorophenol, 3,6-difluorophenol, 2,3,4-trifluorophenol, 2,3,5-trifluorophenol, 2,3,6-trifluorophenol, 2,3,4,5-tetrafluorophenol, 2,3,4,6-tetrafluorophenol, 2,3,5,6-tetrafluorophenol, pentafluorophenol, 2-(trifluoromethyl)phenol, 3 -(trifluoromethyl)phenol, 4-(trifluoromethyl)phenol, 2,3-di(trifluoromethyl)phenol, 2,4-di(trifluoromethyl)phenol, 2,5-di(trifluoromethyl)phenol, 2,6-di(trifluoromethyl)phenol, 2,3,4-tri(trifluoromethyl)phenol, 2,3,5-tri(trifluoromethyl)phenol, 2,3,6-tri(trifluoromethyl)phenol, 2,3,4,5-tetra(trifluoromethyl)phenol, 2,3,4,6-tetra(trifluoromethyl)phenol, 2,3,5,6-tetra(trifluoromethyl)phenol, penta(trifluoromethyl)phenol, and the like.

[0159] Specific examples of fluorine-containing phenolic compounds containing two hydroxyl groups in one molecule include the following compounds. 3-Fluorocatechol, 4-Fluorocatechol, 3,4-Difluorocatechol, 3,5-Difluorocatechol, 3,6-Difluorocatechol, 3,4,5-Trifluorocatechol, 3,4,6-Trifluorocatechol, Tetrafluorocatechol, 3-(Trifluoromethyl)catechol, 4-(Trifluoromethyl)catechol, 3,4-Di(trifluoromethyl)catechol, 3,5-Di(trifluoromethyl)catechol, 3,6-Di(trifluoromethyl)catechol, 3,4,5-Tri(trifluoromethyl)catechol Catechol, 3,4,6-tri(trifluoromethyl)catechol, tetra(trifluoromethyl)catechol, 2-fluororesorcinol, 4-fluororesorcinol, 5-fluororesorcinol, 2,4-difluororesorcinol, 2,5-fluororesorcinol, 4,5-difluororesorcinol, 4,6-difluororesorcinol, 5,6-difluororesorcinol, 2,4,5-trifluororesorcinol, 4,5,6-trifluororesorcinol, tetrafluororesorcinol, 2-(trifluoromethyl)resorcinol, 4-(trifluoromethyl) Resorcinol, 5-(trifluoromethyl)resorcinol, 2,4-di(trifluoromethyl)resorcinol, 2,5-(trifluoromethyl)resorcinol, 4,5-di(trifluoromethyl)resorcinol, 4,6-di(trifluoromethyl)resorcinol, 5,6-di(trifluoromethyl)resorcinol, 2,4,5-tri(trifluoromethyl)resorcinol, 4,5,6-tri(trifluoromethyl)resorcinol, tetra(trifluoromethyl)resorcinol, 2-fluorohydroquinone, 3-fluorohydroquinone, 2,3-difluoro Hydroquinone, 2,5-difluorohydroquinone, 2,6-difluorohydroquinone, 2,3,5-trifluorohydroquinone, 2,3,6-trifluorohydroquinone, tetrafluorohydroquinone, 2-(trifluoromethyl)hydroquinone, 3-(trifluoromethyl)hydroquinone, 2,3-di(trifluoromethyl)hydroquinone, 2,5-di(trifluoromethyl)hydroquinone, 2,6-di(trifluoromethyl)hydroquinone, 2,3,5-tri(trifluoromethyl)hydroquinone, 2,3,6-Tri(trifluoromethyl)hydroquinone, tetra(trifluoromethyl)hydroquinone, 1,3-bis(2-hydroxyhexafluoroisopropyl)benzene, 1,4-bis(2-hydroxyhexafluoroisopropyl)benzene, 2-fluoro-1,5-dihydroxynaphthalene, 3-fluoro-1,5-dihydroxynaphthalene, 4-fluoro-1,5-dihydroxynaphthalene, 2,3-difluoro-1,5-dihydroxynaphthalene, 2,4-difluoro-1,5-dihydroxynaphthalene, 2,6-difluoro-1,5-dihydro xynaphthalene, 2,7-difluoro-1,5-dihydroxynaphthalene, 2,8-difluoro-1,5-dihydroxynaphthalene, 3,4-difluoro-1,5-dihydroxynaphthalene, 3,8-difluoro-1,5-dihydroxynaphthalene, 4,8-difluoro-1,5-dihydroxynaphthalene, 2,3,4-trifluoro-1,5-dihydroxynaphthalene, 2,3,6-trifluoro-1,5-dihydroxynaphthalene, 2,3,7-trifluoro-1,5-dihydroxynaphthalene, 2,3,8-trifluoro-1,5-dihydroxynaphthalene tetrafluoro-1,5-dihydroxynaphthalene, hexafluoro-1,5-dihydroxynaphthalene, 1-fluoro-2,6-dihydroxynaphthalene, 3-fluoro-2,6-dihydroxynaphthalene, 4-fluoro-2,6-dihydroxynaphthalene, 1,3-difluoro-2,6-dihydroxynaphthalene, 1,4-difluoro-2,6-dihydroxynaphthalene, 1,5-difluoro-2,6-dihydroxynaphthalene, 3,4-difluoro-2,6-dihydroxynaphthalene, 3,5-difluoro-2,6-dihydroxynaphthalene 4,5-difluoro-2,6-dihydroxynaphthalene, 1,3,4-trifluoro-2,6-dihydroxynaphthalene, 1,3,5-trifluoro-2,6-dihydroxynaphthalene, 3,4,5-trifluoro-2,6-dihydroxynaphthalene, 1,3,4,5-tetrafluoro-2,6-dihydroxynaphthalene, hexafluoro-2,6-dihydroxynaphthalene, 2,3,4,5-tetrafluorobiphenol, 2,2',4,4'-tetrafluoro-4,4'-biphenol, 2,2',3,3',4,4',5,5',6,6'-octafluoro-4,4'-biphenol, 4,4'-bis(2-hydroxyhexafluoroisopropyl)diphenyl, bis(2,3-difluoro-4-hydroxy)methane, bis(2,6-difluoro-4-hydroxy)methane, bis(3,5-difluoro-4-hydroxy)methane, bis(tetrafluoro-4-hydroxy)methane, 4,4'-bis(2-hydroxyhexafluoroisopropyl)diphenyl ether, 4,4'-isopropylidenebis(2,6-difluorophenol), etc. Examples of compounds containing one hydroxyl group per molecule include the above compounds in which one hydroxyl group has been substituted with hydrogen or halogen.

[0160] Among the above halogen-containing aryl compounds, halogen-containing phenol compounds are preferred, halogen-containing phenol compounds containing one hydroxyl group per molecule are more preferred, and fluorine-containing phenol compounds containing one hydroxyl group per molecule are even more preferred. Among these, pentafluorophenol is particularly preferred.

[0161] <Catalyst for olefin polymerisation> Specific examples of olefins that can be used in the olefin polymerization reaction using the olefin polymerization catalyst of the present invention include vinyl compounds such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, vinylcyclohexene, styrene, 1-octene, and 1-decene, and internal olefins such as 2-butene, cyclopentene, cyclohexene, and norbornene. Among these, ethylene is preferred. Two or more olefins may be co-polymerized.

[0162] <Method for producing olefin polymers> The method for producing an olefin polymer of the present invention comprises a step of carrying out an olefin polymerization reaction (preferably a trimerization to tetramerization reaction, more preferably a tetramerization reaction) in the presence of the above-described olefin polymerization catalyst.

[0163] Specific examples of the olefin to be polymerized are as described above, and ethylene is preferred. Specifically, it is preferable to produce a polymer by polymerizing ethylene, it is more preferable to produce 1-hexene and 1-octene with high selectivity by trimerizing and tetramerizing ethylene, and it is particularly preferable to produce 1-octene with high selectivity by tetramerizing ethylene.

[0164] In olefin polymerization, the order in which component (A), component (B), component (C), and other components (e.g., carrier (D), component (E), and component (F)) are added to the reactor is not particularly limited. Specific examples of the addition method are as follows.

[0165] (1) A method in which components (A), (B), and (C) are added directly to a reactor in any order. (2) A method in which a transition metal complex formed by contacting component (A) with component (B) in advance and a component contacted with component (C) are added to a reactor in any order. (3) A method in which a catalyst component in which component (C) is previously contacted with a transition metal complex formed by previously contacting component (A) with component (B), and a component in which component (C) and component (F) are previously contacted are added to a reactor in any order. In this case, each component (C) may be the same or different. (4) A method in which component (A) and component (B) are brought into contact with each other to form a transition metal complex, which is then supported on a carrier (D), and component (C) are added to a reactor. (5) A method in which a transition metal complex formed in advance by contacting component (A) with component (B) and a support (D) carrying component (C) are added to a reactor in any order. (6) A method in which the carrier (D) carrying component (C), component (A), and component (B) are added to a reactor in any order. (7) A method in which the carrier (D) carrying component (C), component (A), component (B), and the component contacted with component (C) are added to a reactor in any order, in which each component (C) may be the same or different. (8) A method in which a carrier (D) carrying a transition metal complex formed in advance by contacting component (A) with component (B) and a carrier (D) carrying component (C) are added to a reactor in any order.

[0166] In the present invention, olefin polymers are obtained by polymerizing olefins in the presence of the above-described catalyst for olefin polymerization. Olefin polymerization can be carried out by a solution reaction or a suspension reaction. The reaction can be carried out by either a liquid phase reaction method or a gas phase reaction method such as those mentioned above.

[0167] In liquid-phase reaction methods, an inert hydrocarbon medium is usually used. Specific examples of inert hydrocarbon media include aliphatic hydrocarbons such as propane, butane, isobutane, pentane, isopentane, hexane, heptane, octane, decane, dodecane, and kerosene; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclohexane, and methylcyclopentane; aromatic hydrocarbons such as benzene, toluene, xylene, trimethylbenzene, and tetralin; halogenated hydrocarbons such as ethylene chloride, chlorobenzene, and dichloromethane, or mixtures thereof. Among these, linear saturated hydrocarbons having 5 to 7 carbon atoms such as pentane, n-hexane, and n-heptane; and alicyclic saturated hydrocarbons such as methylcyclohexane are preferred.

[0168] When 1-hexene or 1-octene is produced, for example, by the trimerization or tetramerization of ethylene using an olefin polymerization catalyst, the chromium atoms in component (A) are usually 10 -12 ~10 -2 moles, preferably 10 -10 ~10 -3 In the present invention, even when component (A) is used at a relatively low concentration, olefin polymers can be obtained with high activity.

[0169] Component (B) is used in an amount such that the molar ratio [(B) / M] to the chromium atoms (M) in component (A) is generally 0.1 to 10, preferably 0.5 to 2.

[0170] Component (C) is used in an amount such that the molar ratio of metal atoms in component (C) to chromium atoms (M) in component (A) [(C) / M] is generally 10 to 500,000, preferably 20 to 100,000.

[0171] In the present invention, the preferred [(C) / M] molar ratio is 10 to 3000. The lower limit of this molar ratio is more preferably 50, and even more preferably 80. On the other hand, the upper limit of this molar ratio is more preferably 2000, even more preferably 1000, and particularly preferably 800.

[0172] In the olefin oligomerization reaction of the present invention, it is preferable to use the component (C-1) in combination. When component (C-1) is used, component (C-1) is used in an amount such that the molar ratio of component (C-1) to chromium atoms (M) in component (A) [(C-1) / M] is generally 0.01 to 100,000, preferably 0.05 to 50,000.

[0173] When component (C-2) is used, component (C-2) is used in an amount such that the molar ratio of aluminum atoms in component (C-2) to chromium atoms (M) in component (A) [(C-2) / M] is generally 10 to 500,000, preferably 20 to 100,000.

[0174] In the present invention, the preferred [(C-2) / M] molar ratio is 10 to 3000. The lower limit of this molar ratio is more preferably 50, and even more preferably 80. On the other hand, the upper limit of this molar ratio is more preferably 2000, even more preferably 1000, and particularly preferably 800. Usually, it is often necessary to use a relatively large amount of compound (C-2), but with the configuration of the present invention, the reaction can proceed with high activity even when a relatively small amount is used.

[0175] When component (C-3) is used, component (C-3) is used in an amount such that the molar ratio of component (C-3) to chromium atoms (M) in component (A) [(C-3) / M] is generally 1 to 10, preferably 1 to 5.

[0176] When component (D) is used, it is used in an amount such that the ratio (g) of the mass of component (D) per mole of chromium atoms (M) in component (A) (g / mol) is usually 100 to 10,000, preferably 1,000 to 5,000.

[0177] The reaction pressure is usually atmospheric pressure to 10 MPa, preferably atmospheric pressure to 6 MPa, and more preferably atmospheric pressure to 5 MPa. The lower limit is preferably 0.5 MPa, more preferably 0.9 MPa, and particularly preferably 1.5 MPa. The most preferable upper limit is 4 MPa. With the catalyst of the present invention, the higher the reaction pressure, the higher the production efficiency of 1-octene tends to be. It is presumed that 1-octene is obtained via metallacyclononane, which is produced by the coordination of two ethylene molecules to metallacyclopentane and the subsequent concerted (or sequential) insertion of ethylene. The reason why a higher reaction pressure is more effective is not necessarily clear, but it is presumed to be because the structure of the catalyst of the present invention is such that the coordination of two ethylene molecules to metallacyclopentane becomes more favorable as the pressure increases.

[0178] The polymerization reaction can be carried out in any of batch, semi-continuous and continuous systems.

[0179] The polymerization reaction may be carried out in the presence of an antistatic agent. Specific examples of antistatic agents include polypropylene glycol, polypropylene glycol distearate, ethylenediamine-PEG-PPG-block copolymer, stearyldiethanolamine, lauryldiethanolamine, alkyldiethanolamide, and polyoxyalkylenes (e.g., polyethylene glycol-polypropylene glycol-polyethylene glycol block copolymer (PEG-PPG-PEG)). Among these, polyoxyalkylenes (e.g., PEG-PPG-PEG) are preferred. The antistatic agent is used in an amount such that the ratio (g) of the mass of the antistatic agent to the moles of chromium atoms (M) in component (A) (g / mol) is typically 100 to 10,000, preferably 100 to 1,000.

[0180] The polymerization reaction may be carried out with the addition of hydrogen. The hydrogen pressure in the reaction is usually 0.01 MPa to 5 MPa, preferably 0.01 MPa to 1 MPa. The use of hydrogen may further reduce the amount of polyolefin. In addition, since the molecular weight of the by-produced polyolefin is expected to be lower, in the case of liquid phase polymerization using a hydrocarbon as a solvent, the polyolefin becomes more soluble in the solvent, which is expected to suppress adhesion of the polyolefin to the reaction apparatus, etc.

[0181] The olefin polymerization catalyst of the present invention can be used to produce, for example, ethylene trimers and tetramers, such as 1-hexene and 1-octene, with high activity in the polymerization of ethylene. It also reduces the amount of ethylene polymer by-product. The by-product ethylene polymer may have a low melting point as determined by differential scanning calorimetry (DSC). This is thought to indicate that the by-product ethylene polymer has a branched structure and a relatively low molecular weight. It is well known that ethylene polymers with a branched structure or low molecular weight tend to be easily dissolved in inert hydrocarbon media used as reaction solvents. The reason for this tendency is currently unknown, but the present inventors speculate as follows. It is well known that olefin polymerization catalysts generally have higher reactivity with olefins with small carbon numbers, such as ethylene, than with olefins with large carbon numbers, enabling the efficient production of 1-hexene, 1-octene, and the like, through the polymerization of ethylene. The olefin polymerisation catalyst of the present invention, which uses the component (C), may react with some of the higher olefins produced by the polymerisation reaction, including 1-hexene and 1-octene, to produce branched ethylene polymers as by-products.

[0182] As mentioned above, when the by-product ethylene polymer adheres to an olefin polymerization reactor or a heat exchanger, it reduces the thermal conductivity of these devices, which can cause problems when the reactor is operated continuously for a long period of time. To solve this problem, for example, in a liquid-phase reaction, a method is known in which the temperature around the reactor or the heat exchanger is increased to dissolve the by-product ethylene polymer in a solvent. On the other hand, the activity of an olefin polymerization catalyst containing an olefin polymerization catalyst may decrease if the reaction temperature is too high.

[0183] As described above, the method of the present invention can reduce the amount of ethylene polymer produced as a by-product, and therefore it is believed that adhesion of the by-product ethylene polymer to the reactor and heat exchanger can be easily suppressed. This suggests the possibility of efficient and stable production of higher olefins, and the present invention will make a significant contribution to the production of olefin polymers. [Example]

[0184] The present invention will be specifically described below based on examples, but the present invention is not limited to these examples.

[0185] (Gas Chromatography) The yield (amount produced) of the reaction product and the selectivity for 1-hexene and 1-octene were analyzed by a conventional method using gas chromatography (Shimadzu GC-14A, J&W Scientific DB-5 column).

[0186] (DSC measurement) The melting point of the ethylene polymer was measured by differential scanning calorimetry (DSC measurement) using the following apparatus and conditions. Measurement equipment: PerkinElmer Diamond DSC type equipment Uses PerkinElmer aluminum pan. Amount of sample used: Accurately weigh out approximately 10 mg. Temperature raising / lowering method: First stage: The temperature is raised from room temperature to 200°C at a rate of 500°C / min and maintained at this temperature for 10 minutes. Second step: Reduce the temperature to -40°C at a rate of 10°C / min and hold for 1 minute. Third stage: Heat to 150°C at 10°C / min and finish. For other items, DSC profiles were obtained using standard methods, and the heat of fusion (ΔHm: value at the third stage) and other parameters were measured.

[0187] (Selectivity for 1-hexene or 1-octene) The selectivity for 1-hexene or 1-octene was calculated according to the following formula. S(%)=Wp / Wr×100 S (%): 1-hexene or 1-octene selectivity (mass fraction) Wr (mass): The total mass of products produced by the reaction that have 4 or more carbon atoms Wp (mass): Mass of 1-hexene or 1-octene produced by the reaction

[0188] [Example 1] The following amine compound (B-1) was obtained by the method of Synthesis Example 12 of Patent Document 3.

[0189] [ka]

[0190] (Preparation of chromium compounds (mixture)) A thoroughly dried 100 mL Schlenk tube was charged with 0.58 g (3.66 mmol) of the amine compound (B-1), 1.31 g (3.39 mmol) of chromium trichloride tristetrahydrofuran (component (A)), and 68 mL of dichloromethane, and the mixture was stirred for 20 hours at room temperature (20-25°C) under an argon atmosphere. The reaction mixture was concentrated to approximately 1 / 10 of its original volume under reduced pressure, and then 15 mL of n-hexane was added and the mixture was stirred for a while. The insoluble matter was filtered off using a glass filter. After washing with 20 mL of n-hexane and drying under reduced pressure, 0.93 g of the chromium compound as a transition metal compound was obtained. Got it.

[0191] (Ethylene polymerisation reaction) A 100 mL autoclave, thoroughly purged with nitrogen, was charged with 30 mL of methylcyclohexane, and triisobutylaluminum was added in an amount of 0.03 mmol, calculated as aluminum atoms. Next, under an argon atmosphere, a predetermined amount of the chromium compound and a predetermined organoaluminum compound (TEA: component (C-1)) were added to a thoroughly dried Schlenk flask and contacted, and the entire contact liquid was added to the autoclave. Furthermore, a predetermined halogen-containing organoaluminum compound (C-α: component (C)) was added to the autoclave in an amount equivalent to 0.004 mmol, calculated as aluminum atoms. The predetermined amount is specified by the amount of aluminum-containing compound, aluminum / chromium ratio, and amount of halogen-containing organoaluminum, as shown in Table 1.

[0192] Ethylene was supplied to the autoclave to pressurize it, and the autoclave was heated to 60°C. The pressure inside the reactor was maintained at 60°C for 60 minutes while ethylene was supplied so as to maintain the pressure inside the reactor at 0.8 MPa-G. Thereafter, the pressure was released to remove unreacted ethylene, and a small amount of isopropanol was added to terminate the reaction.

[0193] The reaction mixture was then washed with 0.1 N hydrochloric acid and purified water, and the low-boiling components (components with 10 or less carbon atoms) were separated from the high-boiling components and polyethylene using a liquid nitrogen trap under reduced pressure, and analyzed by gas chromatography. The results are shown in Table 1.

[0194] [Example 2, Comparative Examples 1 and 2] The ethylene polymerization reaction was carried out in the same manner as in Example 1, except that the components and their amounts used were as shown in Table 1. The results are shown in Table 1.

[0195] In each of the Examples and Comparative Examples, the following aluminum-containing compounds were used as component (C-1) to be contacted in advance with component (A). TEA: Triethylaluminum (amount added: amount converted to Al atoms)

[0196] In each example and comparative example, the following halogen-containing organoaluminum compound (amount added: amount converted into Al atoms) and borate compound (amount added: amount converted into B atoms) were used as component (C). C-α: Triphenylcarbenium tetrakis((1,1,1,3,3,3-hexafluoro-2-(trifluoromethyl)propen-2-yl)oxy)aluminate C-β: N,N-dimethylanilinium tetrakis((1,1,1,3,3,3-hexafluoro-2-(trifluoromethyl)propen-2-yl)oxy)aluminate C-3-3: Triphenylcarbenium tetrakis(pentafluorophenyl)borate C-3-4: N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate

[0197] The amount of olefin produced in Table 1 indicates the amount of liquid olefin produced having 10 or less carbon atoms.

[0198] [Table 1]

[0199] Among the results in Table 1, the effect of the fluorine-containing organoaluminum compound can be particularly accurately understood by comparing Example 1 with Comparative Example 1, and Example 2 with Comparative Example 2. It can be seen that the amount of ethylene polymer produced as a by-product is smaller in each example than in the comparative example.

[0200] Furthermore, the melting points of the ethylene polymers produced as by-products in the Examples are lower than those of the ethylene polymers produced as by-products in the Comparative Examples. This shows that the method of the present invention is advantageous in terms of dissolving the ethylene polymers produced as by-products in a solvent and removing them. [Industrial Applicability]

[0201] The olefin polymerization catalyst of the present invention can produce specific olefin polymers with high activity and high selectivity. Furthermore, the melting point of the by-product ethylene polymer tends to be low, and it is expected that this ethylene polymer will be easily soluble in solvents even at relatively low temperatures. Therefore, it is expected that the ethylene polymer will not easily adhere to the inner walls of the reactor or heat exchangers, reducing thermal conductivity. Therefore, the present invention is of great industrial value.

Claims

1. A method for producing an olefin polymer, comprising carrying out an olefin polymerization reaction in the presence of an olefin polymerization catalyst containing the following components (A), (B), and (C): (A) a chromium compound, (B) an amine compound represented by the following general formula (1): 【Chemistry 1】 (In general formula (1), R 1 ~R 4 each independently represents a hydrogen atom, a halogen atom, a hydrocarbon group, a heterocyclic compound residue, an oxygen-containing group, a nitrogen-containing group, a boron-containing group, an aluminum-containing group, a sulfur-containing group, a phosphorus-containing group, a silicon-containing group, a germanium-containing group, or a tin-containing group, and two or more of these may be linked to each other. Y is a substituent R 5 and R 6 A carbon atom having a carbon atom (-CR 5 R 6 -) is represented by the formula R 5 and R 6 R each independently represents a hydrogen atom, a halogen atom, a hydrocarbon group, a heterocyclic compound residue, an oxygen-containing group, a nitrogen-containing group, a boron-containing group, an aluminum-containing group, a sulfur-containing group, a phosphorus-containing group, a silicon-containing group, a germanium-containing group, or a tin-containing group. 5 and R 6 may be linked to each other. 5 and R 6 At least one of 1 ~R 4 When Z is an integer of 2 or more, the multiple Ys are each independently defined as above. Z represents an integer of 1 to 10. (C) an organometallic compound specified by the following general formula (2): 【Chemistry 2】 (In general formula (2), I C + is a cation containing an atom of Group 14 or 15 of the periodic table, IA is an atom selected from group 13 elements of the periodic table, R α is a substituent containing a hydrogen atom or an atom selected from the group consisting of atoms in groups 14 to 17 of the periodic table, R h is a halogen-containing hydrocarbon group, m is a positive real number, n is 0 or a positive real number, and 2<m≦4 and m+n=4 are satisfied.

2. 2. The method for producing an olefin multimer according to claim 1, wherein IA is an aluminum atom.

3. The above R h The method for producing an olefin multimer according to claim 1 or 2, wherein is a fluorine-containing hydrocarbon group.

4. R 1 is R 3 and R 4 It is not connected to R 2 is R 3 and R 4 The method for producing an olefin multimer according to any one of claims 1 to 3, wherein the olefin multimer is not linked to

5. The method for producing an olefin multimer according to any one of claims 1 to 4, wherein Z is an integer of 1 to 3.

6. The method for producing an olefin multimer according to any one of claims 1 to 5, wherein Z is 1.

7. The method for producing an olefin multimer according to any one of claims 1 to 6, wherein the olefin is ethylene.

8. A catalyst for olefin polymerisation comprising the following components (A), (B) and (C): (A) a chromium compound, (B) an amine compound represented by the following general formula (1): 【Transformation 3】 (In general formula (1), R 1 ~R 4 each independently represents a hydrogen atom, a halogen atom, a hydrocarbon group, a heterocyclic compound residue, an oxygen-containing group, a nitrogen-containing group, a boron-containing group, an aluminum-containing group, a sulfur-containing group, a phosphorus-containing group, a silicon-containing group, a germanium-containing group, or a tin-containing group, and two or more of these may be linked to each other. Y is a substituent R 5 and R 6 A carbon atom having a carbon atom (-CR 5 R 6 -) is represented by the formula R 5 and R 6 R each independently represents a hydrogen atom, a halogen atom, a hydrocarbon group, a heterocyclic compound residue, an oxygen-containing group, a nitrogen-containing group, a boron-containing group, an aluminum-containing group, a sulfur-containing group, a phosphorus-containing group, a silicon-containing group, a germanium-containing group, or a tin-containing group. 5 and R 6 may be linked to each other. 5 and R 6 At least one of 1 ~R 4 When Z is an integer of 2 or more, the multiple Ys are each independently defined as above. Z represents an integer of 1 to 10. (C) an organometallic compound specified by the following general formula (2): 【Chemistry 4】 (In general formula (2), I C + is a cation containing an atom of Group 14 or 15 of the periodic table, IA is an atom selected from group 13 elements of the periodic table, R α is a substituent containing a hydrogen atom or an atom selected from the group consisting of atoms in groups 14 to 17 of the periodic table, R h is a halogen-containing hydrocarbon group, m is a positive real number, n is 0 or a positive real number, and 2<m≦4 and m+n=4 are satisfied.

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