JPH10338698A - New transition metal compound and olefin polymerization catalyst - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new transition metal compound comprising a specific transition metal compound containing a pyrazolyl group, having a high polymerization activity per transition metal, excellent in copolymerizability and capable of providing a polymer excellent in mechanical strength as an olefin polymerization catalyst, etc. SOLUTION: This is a new transition metal compound of the formula, RQ(Pz)3 MX3 [M is a group IV transition metal in the periodic table; RQ(Pz)3 is a neutral trispyrazolyl ligand having three (substituted) pyrazolyl groups bound with Q; Q is C, Si, Ge, Sn or Pb; R and X are each H, a halogen, a 1-24C alkyl, an aryl, a cycloalkyl, an amino, an oxyhydrocarbon group], (e.g. trispyrazolylmethanetitanium trichloride). The compound is useful as a highly active olefin polymerization catalyst, etc. in combination with an organic aluminumoxy compound, a Lewis acid compound, an ionic compound, etc. The compound is obtained by reacting tris(pyrazolyl)methane, etc. with TiCl3 in a solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel transition metal compound and an olefin polymerization catalyst using the same.

[0002]

2. Description of the Related Art In recent years, metallocene types such as Ti, Zr and Hf, which are highly active as olefin polymerization catalysts, have narrow molecular weight distributions of formed polymers and narrow composition distributions in copolymerization, and are capable of obtaining olefin polymers having excellent physical properties. A catalyst system comprising a combination of a complex and an organic aluminum oxy compound such as methylalumoxane has attracted attention. These are Macromol
ecular Science, 1994, C34, No3, p. 439, Progre
ss Polymer Science, 1995, 20, 309, 459
Page, Journal of Organometallic Chemistry, 1995,
It is described in detail in Volume 497, No. 1-2.

[0003] In addition, Japanese Patent Publication No. 1-501950, 1-502036,
JP-A-3-63088 and JP-A-3-139504 disclose an olefin polymerization comprising a combination with an ammonium salt of an anionic boron compound containing an active proton as an activator or ionizing agent without using an organic aluminum oxy compound. An active catalyst system is disclosed. In JP-A-3-179006, triphenylcarbonium salts of anionic boron compounds containing no active protons, JP-A-3-207703, JP-A-5-503546, JP-A-502906, JP-A-507756, and JP-A-505838 are disclosed. Further, a catalyst system to which organoaluminum is added is disclosed.

Among the complexes that form a homogeneous catalyst, complexes having a nitrogen bond with a transition metal include those described in JP-A-3-501269.
No., JP-A-2-77412, JP-A-4-285607, JP-A-5-331225,
6-73127, 6-128324, 6-157632, and 6-
199939, further as a complex having at least one cyclopentadienyl group and a transition metal and a nitrogen bond, JP-A-3-63088, JP-A-4-279592, JP-T-Hei 5-505593, JP-A-5-505593
It is described in each gazette such as 507756 and 6-501037. Further, as a complex having a transition metal / nitrogen bond, a titanium or zirconium complex having hydropyrazolyl borate as a ligand is known, but Japanese Patent Application Laid-Open No. 1-95110 discloses that olefin polymerization performance is improved in combination with aluminoxane. JP-A-4-305585 discloses as a syndiotactic polymerization catalyst for styrene, and further disclosed in JP-A-7-70.
No. 224 discloses that a titanium / zirconium complex having both a hydropyrazolyl borate ligand and a cyclopentadienyl ligand is a catalyst for polymerization of ethylene and copolymerization with α-olefin.

On the other hand, the inventors of the present invention disclosed in JP-A-8-127610 and JP-A-8-253524 to assist a titanium complex, a zirconium complex and a ionic compound of ethylene, trispirazolyl borate exhibiting polymerization activity of ethylene and olefin. A catalyst system as a catalyst is proposed. Further, Japanese Patent Application No. 8-28880 discloses a polymerization catalyst system mainly comprising a titanium oxy complex and a zirconium oxy complex of trispirazolylmethane as a neutral ligand.

[0006]

An object of the present invention is to provide a novel transition metal compound containing a pyrazolyl group and an olefin polymerization catalyst having high polymerization activity using the same.

[0007]

Means for Solving the Problems The present invention relates to a transition metal compound represented by the following formula (1). RQ (Pz) ₃ MX ₃ (1) (wherein M is a transition metal belonging to Group 4 of the periodic table, and RQ (P
z) ₃ is a neutral trispirazolyl ligand having three substituted or unsubstituted pyrazolyl groups linked by Q,
Is carbon, silicon, germanium, tin, or lead;
R and X are hydrogen, halogen, an alkyl group having 1 to 24 carbon atoms, an allyl group, a cycloalkyl group, an amino group, or an oxyhydrocarbon group. )

Further, the present invention provides (a) a transition metal compound according to claim 1, (b) an organoaluminum oxy compound capable of forming a cation complex by reacting with the transition metal compound, The present invention relates to an olefin polymerization catalyst comprising a compound or an ionic compound.

Further, the present invention provides (a) a transition metal compound according to claim 1, (b) an organoaluminum oxy compound capable of forming a cation complex by reacting with the transition metal compound, The present invention relates to an olefin polymerization catalyst obtained from a compound or an ionic compound.

The transition metal compound of the present invention is a complex of a transition metal belonging to Group 4 of the periodic table having a neutral trispirazolyl having three substituted or unsubstituted pyrazolyl groups as a ligand, and having an oxidation number of 3. The above three pyrazolyl ligands are bonded to carbon, silicon, germanium, tin or lead atoms as bonding groups.

[0011]

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As the transition metal of Group 4 of the periodic table, titanium (Ti), zirconium (Zr) and hafnium (Hf) are preferable.

The substituted pyrazolyl group bonded to carbon, silicon, germanium, tin, or lead includes 3-, 5-, or
The 3,5-substitution is preferred. Substituents include methyl, ethyl, iso-propyl, butyl, iso-butyl, t-
Examples include a butyl group, a phenyl group, a benzyl group, a 2,6-dimethylphenyl group, and a 2,6-di-isopropylphenyl group.

In the transition metal compound of the present invention, X which is a ligand other than trispirazolyl is hydrogen, chlorine,
Halogen such as bromine, alkyl group having 1 to 24 carbon atoms such as methyl group, ethyl group, iso-propyl group, butyl group, iso-butyl group, t-butyl group, allyl group, cycloalkyl group, diethylamino group, diamino group It is selected from amino groups such as propylamino group and dibutylamino, and oxyhydrocarbon groups such as methoxy group, ethoxy group, propoxy group and butoxy group.

Specific examples of the transition metal compound of the present invention include trispirazolylmethanetitanium trichloride, trispirazolylmethanetitanium methoxydichloride, trispirazolylmethanetitanium ethoxydichloride, trispirazolylmethanetitanium propoxydichloride, trispirazolylmethanetitanium butoxydichloride, Trispyrazolylmethanetitanium dimethoxychloride, trispirazolylmethanetitanium trimethoxide, trispirazolylmethanetitanium triethoxide, trispirazolyl methanetitanium tripropoxide, trispirazolyl methanetitanium tributoxide, trispirazolyl methanetitanium trimethyl, trispirazolyl methanetitanium diethyl The Chloride, trispirazolylmethanetitanium dipropylaminodichloride, trispirazolylmethanetitanium dibutylaminodichloride, tris-3,5-dimethylpyrazolylmethanetitanium trichloride, tris-3,5-dimethylpyrazolylmethanetitanium methoxydichloride, tris-3,5 -Dimethylpyrazolylmethanetitanium ethoxydichloride, tris-3,5-dimethylpyrazolylmethanetitanium propoxydichloride, tris-3,5-dimethylpyrazolylmethanetitanium butoxydichloride, tris-
3,5-dimethylpyrazolylmethanetitanium dimethoxychloride, tris-3,5-dimethylpyrazolylmethanetitanium trimethoxide, tris-3,5-dimethylpyrazolylmethanetitanium triethoxide, tris-3,5
-Dimethylpyrazolylmethanetitanium tripropoxide, tris-3,5-dimethylpyrazolylmethanetitanium tributoxide, tris-3,5-dimethylpyrazolylmethanetitanium trimethyl, tris-3,5-dimethylpyrazolylmethanetitanium diethylaminodichloride, tris- Examples include 3,5-dimethylpyrazolylmethanetitanium dipropylaminodichloride and tris-3,5-dimethylpyrazolylmethanetitanium dibutylaminodichloride.

The method for preparing the transition metal compound of the present invention includes, for example, a 1,1,1-trichloro-substituted hydrocarbon compound, a 1,1,1-trichloro-substituted silicon hydrocarbon compound, and a 1,1,1-trichloro-substituted germanium compound. Hydrocarbon compounds and triple molar amounts of 3-, 5
-Or tris (3-, 5- or 3,5-substituted pyrazolyl) obtained by reaction with a 3,5-substituted pyrazolyl alkali metal salt
An adjustment method for causing a compound to react equimolarly with a transition metal trichloride tetrahydrofuran complex may be mentioned.

The catalyst for olefin polymerization of the present invention comprises (a) the above transition metal compound, (b) an organoaluminum oxy compound capable of forming a cation complex by reacting with the transition metal compound, and a Lewis acidic compound. Or a catalyst system comprising a co-catalyst selected from ionic compounds.

The above-mentioned organoaluminum oxy compound is a linear or cyclic polymer represented by the general formula (-Al (R ² ) O-) m (R ² is a hydrocarbon having 1 to 20 carbon atoms). a group, .m also include those substituted by some halogen atoms and / or R ² O groups are the degree of polymerization, 5 or more, preferably 10 or more). R ² includes a methyl, ethyl, propyl, isobutyl group and the like. Among them, a methyl group is preferable.

The Lewis acidic compound capable of stabilizing the cation of the transition metal compound by removing the ligand of the transition metal compound as an anion is, for example, a fluorine compound of boron or aluminum. Preferably, B (C ₆ F ₅ ) ₃ , Al (C ₆ F
₅ ) ₃ .

The ionic compound capable of reacting with a transition metal compound to form a cationic complex includes a bulky, non-coordinating tetrakis (a well-known anion as a transition metal group 4 transition metal metallocene catalyst system). Pentafluorophenyl) borate, tetrakis (monofluorophenyl)
Borate, tetrakis (difluorophenyl) borate, tetraphenylborate, and aluminates thereof. On the other hand, examples of the cation include N, N- having an active proton such as (alkyl) ₂ N (C ₆ H ₅ ) H ^+.
Dialkylanilinium cation, trialkylammonium cation, triallylphosphonium cation, (C
₆ H _{5) 3} C ⁺ trisubstituted carbonium cations, oxonium cations, sulfonium cations, carborane cation, a metal carborane cation, ferrocenium cation having a transition metal, even primary elemental metals, cations of transition metals and such as Examples thereof include cations to which ethers, amines, and the like are coordinated.

When the ligand X of the transition metal compound does not have at least one hydrocarbon group, the ligand of the transition metal compound may be substituted with a hydrocarbon group beforehand with an organometallic compound. it can. Further, an organometallic compound can be used in combination with a catalyst component as a trapping agent for a solvent, water in a reaction gas, and other catalyst poisons, or as a hydrocarbon agent for a transition metal compound.

Examples of the organometallic compound include organomagnesium, organolithium and organoaluminum, of which organoaluminum is preferred. Examples of the organic aluminum compound include trialkylaluminum, dialkylhalogenoaluminum, sesquialkylhalogenoaluminum, alkenylaluminum, dialkylhydroaluminum, and sesquialkylhydroaluminum.

In the present invention, a transition metal compound and
Alternatively, the promoter can be used by being supported on an inorganic compound or an organic polymer compound. As the inorganic compound, inorganic oxides, inorganic chlorides and inorganic hydroxides are preferable, and those containing a small amount of carbonate and sulfate can also be used. Particularly preferred are inorganic oxides, such as silica, alumina, magnesia, titania, zirconia, and calcia. These inorganic oxides have an average particle size of 5
Porous fine particles having a specific surface area of 2 to 800 m ² / g are preferred, for example, heat-treated at 100 to 800 ° C. for use. As the organic polymer compound of the carrier, those having an aromatic ring, a substituted aromatic ring, or a functional group such as a hydroxy group, a carboxyl group, an ester group, or a halogen atom in a side chain are preferable. As specific examples, ethylene, propylene, α-olefin homopolymer having the functional group by chemical modification such as polybutene, α-olefin copolymer, acrylic acid, methacrylic acid, vinyl chloride, vinyl alcohol, styrene, homopolymer such as divinylbenzene, Copolymers and their chemically modified products can be mentioned. As these organic polymer compounds, spherical fine particles having an average particle diameter of 5 to 250 μm are used.

In the present invention, olefin polymerization includes olefin polymerization and copolymerization.

As a polymerization method, a gas phase method, a slurry method,
A solution method or the like can be adopted. In the gas phase method, for example, an organoaluminum compound and / or a catalyst in which a co-catalyst and a transition metal compound are supported on the carrier is prepared, and the organoaluminum compound and / or olefin gas are mixed in a stirred or fluidized bed type gas phase polymerization tank. The polymerization can be carried out by contact. The gas phase polymerization is usually carried out at a temperature of 20 to 100 ° C. for a time of 20 to 360 °.
The polymerization is carried out under the conditions of a polymerization pressure of normal pressure to 5.1 MPa.

In the slurry method or the solution method, for example, a co-catalyst and a transition metal compound are added to an inert hydrocarbon solvent in which an organoaluminum compound and / or an olefin gas is dissolved, or a pre-contact is added. To carry out polymerization. Normal polymerization conditions are at a temperature of 20
~ 250 ° C, time 1 ~ 120 minutes, polymerization pressure is normal pressure ~ 15.3Mpa
Wherein the inert hydrocarbon solvent is propane, butane, pentane, hexane, heptane, cyclohexane or the like.

The amount of the cocatalyst used for the transition metal compound is 10 to 10,000, preferably 30 to 3,000 in terms of the Al / transition metal atomic ratio in the case of the organoaluminum oxy compound, and in the case of the Lewis acidic compound or the ionic compound, It is preferably about 1 to 10 times the transition metal compound. The amount of the organoaluminum compound used in combination is from 1 to 5000, preferably from 5 to 1000, in terms of Al / transition metal atomic ratio.

In any of the above polymerization methods, hydrogen can be used as a molecular weight regulator. Further, prior to the main polymerization of the olefin, the activity can be enhanced by using a prepolymerized olefin according to the above-mentioned various polymerization methods as a catalyst. The prepolymerization may be carried out, for example, in a slurry method in an inert hydrocarbon solvent, usually at 5 to 80 ° C. for 5 to 60 minutes, under the conditions that 1 to 100 g of olefin polymer is obtained per 1 mg atom of transition metal of the catalyst. it can.

Specific examples of the olefin in the present invention include:
Ethylene, propylene, butene-1, 4-methylpentene
1, acyclic monoolefins such as hexene-1 and octene-1, and cyclic monoolefins such as cyclopentene, cyclohexene and norbornene. Also,
In the above-mentioned olefin polymerization and copolymerization, a smaller amount of dicyclopentadiene, 5-ethylidene-2 norbornene,
Alternatively, a non-conjugated diolefin such as 1,5 hexadiene can be copolymerized.

[0030]

According to the present invention, when an olefin polymer is produced using the transition metal compound of the present invention as a catalyst, the polymerization activity per transition metal is high, the copolymerizability of ethylene and α-olefin is excellent, and the mechanical properties are excellent. The resulting polymer is obtained.

[0031]

EXAMPLES In the examples, "polymerization activity" refers to the yield (g) of polymer per 1 mmol of transition metal of the transition metal compound used in the polymerization reaction. The molecular weight distribution is the weight average molecular weight determined from GPC using polystyrene as a standard.
It was evaluated by the ratio Mw / Mn of Mw and the number average molecular weight Mn. The composition of the copolymer was calculated from the peak area ratio of a methyl group, a methylene group, and a methine group measured by ¹ H-NMR.

Example 1 [Synthesis of transition metal compound] [HC (Pz) ₃ ] TiCl ₃ Organic Preparations and Procedures International,
179 mg (0.84 mmol) of tris (pyrazolyl) methane obtained by the method described in 1984, Vol. 16, page 299, and T
iCl ₃ · 3THF 310 mg of (0.84 mmol) was dissolved in 1,2-dichloroethane 20 ml under a stream of nitrogen. Initially, the suspension became purple, but then turned into a blue suspension. The mixture was heated under reflux for about 24 hours, and the formed blue precipitate was separated by filtration and THF / CH ₂ Cl ₂ (2/1)
And then vacuum dried. The analysis results are as follows. IR (KBr disk): 3381 (br), 3145 (sh), 3123 (s), 2990
(s), 1639 (br), 1515 (s), 1443 (s), 1410 (s), 1397 (s
h), 1367 (w), 1280 (s), 1247 (s), 1222 (s), 1099 (s), 1
083 (s), 987 (s), 944 (w), 919 (w), 907 (w), 857 (s), 79
1 (s), 775 (s), 658 (s), 605 (s) cm ^-1

[0033]

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Example 2 [Synthesis of transition metal compound] [HC (3,5-Me ₂ Pz) ₃ ] TiCl ₃ Organic Preparations and Procedures International,
90 mg of tris (3,5-dimethylpyrazolyl) methane obtained by the method described in 1984, Vol. 16, page 299 (0.42
mmol) and TiCl ₃ · 3THF 155 mg of (0.42 mmol) was dissolved in 1,2-dichloroethane 10 ml under a stream of nitrogen. Initially, the suspension became purple, but then turned into a blue suspension. About 24
The mixture was heated at reflux for a period of time, and the resulting blue precipitate was filtered off.
After washing with CH ₂ Cl ₂ (2/1), vacuum drying was performed. The analysis results are as follows. IR (KBr disk): 3407 (br), 3135 (s), 2926 (s), 1637 (b
r), 1564 (s), 1460 (s), 1413 (s), 1395 (sh), 1384 (s), 1
300 (s), 1258 (s), 1106 (w), 1046 (s), 984 (s), 946 (w),
910 (s), 859 (s), 830 (w), 803 (w), 788 (s), 703 (s), 66
6 (w), 630 (w), 596 (w), 489 (s) cm ^-1 EA: Calcd for C ₁₆ H ₂₂ Cl ₃ N ₆ Ti (CH ₂ Cl ₂ ) _0.15 : C, 41.6
8; H, 4.83; N, 18.06% Found: C, 41.78; H, 4.65;
N, 17.96%

[0035]

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Example 3 To 200 ml of toluene was added 10 mM of methylalumoxane (manufactured by Tosoh Akzo Co., Ltd.) as a toluene solution.
The solution was kept at 40 ° C. while flowing hydrogen gas (1 L / min., 50 ml / min. Respectively). 10 μmol of the transition metal compound of Example 1 was added as a toluene solution, and polymerization was performed for 60 minutes. The polymerization was stopped with an ethanol solution containing HCl,
After filtration and drying, a white ethylene polymer was obtained. Table of results
Shown in 1.

Example 4 To 200 ml of toluene was added 10 mM of methylalumoxane (manufactured by Tosoh Akzo Co., Ltd.) as a toluene solution.
The solution was kept at 40 ° C. while flowing hydrogen gas (1 L / min., 50 ml / min., Respectively). 10 μmol of the transition metal compound of Example 2 was added as a toluene solution, and polymerization was carried out for 60 minutes. The polymerization was stopped with an ethanol solution containing HCl, filtered and dried to obtain a white ethylene polymer. Table 1 shows the results.

Example 5 To 200 ml of toluene was added 10 mM of methylalumoxane (manufactured by Tosoh Akzo) as a toluene solution, and the solution was heated to 40 ° C. while flowing a mixed gas (1/3) of ethylene and propylene.
Kept. 10 μmol of the transition metal compound of Example 1 was added as a toluene solution and copolymerized for 60 minutes. HCl
The polymerization was stopped with the contained ethanol solution, filtered and dried to obtain a white ethylene-propylene copolymer. Table 1 shows the results
Shown in

Example 6 To 200 ml of toluene was added 10 mM of methylalumoxane (manufactured by Tosoh Akzo Co., Ltd.) as a toluene solution, and the solution was heated to 40 ° C. while flowing a mixed gas (1/3) of ethylene and propylene.
Kept. 10 μmol of the transition metal compound of Example 2 was added as a toluene solution and copolymerized for 60 minutes. HCl
The polymerization was stopped with the contained ethanol solution, filtered and dried to obtain a white ethylene-propylene copolymer. Table 1 shows the results
Shown in

Example 7 After adding 0.3 mM of triisobutylaluminum in place of methylalumoxane, 10% of (C ₆ H ₅ ) ₃ CB (C ₆ F ₅ ) ₄ was added.
Ethylene polymerization was carried out in the same manner as in Example 3 except that μmol was added as a toluene solution. Table 1 shows the results.

Example 8 After adding 0.3 mM of triisobutylaluminum instead of methylalumoxane, 10% of (C ₆ H ₅ ) ₃ CB (C ₆ F ₅ ) ₄ was added.
Ethylene polymerization was carried out in the same manner as in Example 4 except that μmol was added as a toluene solution. Table 1 shows the results.

[0042]

[Table 1]

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08F 10/00 C08F 10/00

Claims (3)

[Claims] 1. A transition metal compound represented by the following formula (1). RQ (Pz) ₃ MX ₃ (1) (wherein M is a transition metal belonging to Group 4 of the periodic table, and RQ (P
z) ₃ is a neutral trispirazolyl ligand having three substituted or unsubstituted pyrazolyl groups linked by Q,
Is carbon, silicon, germanium, tin, or lead;
R and X are hydrogen, halogen, an alkyl group having 1 to 24 carbon atoms, an allyl group, a cycloalkyl group, an amino group, or an oxyhydrocarbon group. ) (2) The transition metal compound according to (1),
And (b) an organoaluminum oxy compound capable of reacting with the transition metal compound to form a cation complex,
An olefin polymerization catalyst comprising a Lewis acidic compound or an ionic compound. (3) The transition metal compound according to (1),
And (b) an organoaluminum oxy compound capable of reacting with the transition metal compound to form a cation complex,
An olefin polymerization catalyst obtained from a Lewis acidic compound or an ionic compound.