JPH0725932A - Polymerization of ethylene and catalytic component therefor - Google Patents

Abstract

PURPOSE:To provide a catalytic component for ethylene polymerization composed of a VIII group transition metal compound and a specified compound, exhibiting a high polymerization activity and capable of synthesizing a high- molecular PE having branches such as methyl branches in a high yield. CONSTITUTION:The catalytic component is composed of (A) a VIII group transition metal compound such as bis(1,5-cyclooctadiene)nickel (0) and (B) a compound of the formula (R1 to R4 are each a 1 to 20C n-alkyl, a 1 to 20C isoalkyl, a 1 to 20C tert-alkyl, a 1 to 20C trialkylsilyl, a 6 to 12C aryl, H or vinyl), e.g. [bis(trimethylsily)amino](t-butylimino)(trimethylsilylimino)phosphorane. In addition, the ratio of the component (A) to (B) is preferably within a range of 1/1 to 100 and ethylene is polymerized preferably in the presence of this catalytic component.

Description

Detailed Description of the Invention

[0001]

The present invention relates to methyl branching and side chain length C
_The present invention relates to a catalyst component capable of producing a high molecular weight ethylene polymer having ₆ or more branches in a high yield, and a method for polymerizing ethylene using the same.

[0002]

2. Description of the Related Art Generally, a low-density polyethylene (LDPE) having a long chain branch having a length equal to that of a polymer main chain.
Is produced by high temperature high pressure radical polymerization.
On the other hand, high-density polyethylene (HDPE) obtained by polymerization using a transition metal catalyst (Ziegler-Natter catalyst, metallocene catalyst, etc.) under low temperature and low pressure conditions has almost no branching. In addition, in polyethylene (LLDPE) obtained by copolymerization with α-olefin using these catalysts, LDPE
It is not possible to impart the same long-chain branch as the main chain.

As an attempt to produce such a polyethylene having a long chain branch at low temperature and low pressure, for example, JP-A-2-26 is known.
1809, 2-206607, 3-115311, and 3-277610, there is a method for producing polyethylene having a long-chain branch having a carbon number of C ₆ or more with a nickel-based catalyst.

[0004]

However, there are problems that the activity of these catalyst components is low and that the polymer produced has a low molecular weight. An object of the present invention is to provide a novel catalyst and a method for producing polyethylene, which eliminates such drawbacks.

[0005]

The ethylene polymerization catalyst component according to the present invention is characterized by comprising a Group VIII transition metal compound and the following general formula (I).

[0006]

[Chemical 2]

The ethylene polymerization method according to the present invention is a polymerization method of ethylene characterized by polymerizing ethylene in the presence of the above-mentioned catalyst component for ethylene polymerization. Further, in polymerizing ethylene, the above-mentioned polymerization catalyst is used. A method for polymerizing ethylene, which comprises polymerizing ethylene in the presence of components and, if necessary, a reducing agent and / or an electron donating compound.

Further, in the ethylene polymerization method according to the present invention, the transition metal compound of Group VIII in the ethylene polymerization catalyst component of the present invention is a divalent nickel compound, and the compound is represented by the general formula (I) and a reducing agent. Or an ethylene polymerization method characterized in that the transition metal compound of Group VIII is a zero-valent nickel compound and is carried out in the presence of the general formula (I) and an electron donating compound. It is a polymerization method.

The Group VIII transition metal compounds used in the present invention include nickel compounds, palladium compounds,
Examples include platinum compounds, cobalt compounds, iron compounds, and the like. Of these, nickel compounds and palladium compounds are preferably used. Particularly preferred is a nickel compound, specifically, bis (1,5-cyclooctadiene) nickel (0), bis (cyclooctatetraene) nickel (0), cyclododecatriene (triphenylphosphine) nickel (0). ), Tetracarbonyl nickel (0), dicarbonyl bis (triphenylphosphine)
Nickel (0), tetrakis (triphenylphosphine) nickel (0), μ (dinitrogen) bis [bis (tricyclohexylphosphine) nickel (0)], tetrakis (t-butylisocyanide) nickel (0), dicarbonyl Bis (t-butyl cyanide) nickel (0), bis (t-butyl cyanide) nickel (0), (η-ethylene) bis (triphenylphosphine) nickel (0), bis (acrylonitrile) nickel (0) , Bis (acetylacetonato) nickel (I
I), nickel (II) acetate, nickel (II) stearate, dibromobis (triphenylphosphine) nickel (II), hydridotetrakis (triethylphosphonate) phosphoric acid nickel (II), trans- [chlorohydridobis (tricyclohexyl) Phosphine) nickel (II)], trans- [chloro (phenyl)]
Bis (triphenylphosphine) nickel (II)],
trans- [Bromo-o-tolyl (triethylphosphine) nickel (II)], dimethylbis (trimethylphosphine) nickel (II), diethyl (2,2′-)
Bipyridyl) nickel (II), di-η-bromobis (allyl) dinickel (II), bis (allyl) nickel (II), tetrachlorobis (tetramethylcyclobutadiene) dinickel (II), bis (η-cyclo) Pentadienyl) nickel (II), chloro ((eta) -cyclopentadienyl) (triphenylphosphine) nickel (II), allyl ((eta) -cyclopentadienyl) nickel (II), etc. are mentioned.

As the palladium compound, (ethylene)
Bis (triphenylphosphine) palladium (0), carbonyltris (triphenylphosphine) palladium (0), tris (dibenzylideneacetone) dipalladium (0), bis (t-butyl cyanide) palladium (0), dichloro ( 1,5-cyclooctadiene) palladium (II), di-μ-chloro-dichlorobis (triphenylphosphine) dipalladium (II), dichloro (tetraphenylcyclobutadiene) palladium (I
I), di-μ-chloro-dichlorobis (allyl) dipalladium (II), dichlorobis (benzonitrile) palladium (II), bis (allyl) palladium (II) and the like. Of these, preferably bis (1,5-
Cyclooctadiene) nickel (0) and bis (acetylacetonato) nickel (II) are used.

As the compound represented by the general formula (I), R ₁ , R ₂ , R ₃ and R ₄ are an n-alkyl group having 1 to 20 carbon atoms, an iso-alkyl group having 1 to 20 carbon atoms, and a carbon number. A tert-alkyl group having 1-20, a trialkylsilyl group having 1-20 carbon atoms, or an aryl group having 6-12 carbon atoms, hydrogen, or any combination of vinyl and at least one has a tert-alkyl group. Specifically, [bis (trimethylsilyl) amino]
(T-Butylimino) (trimethylsilylimino) phosphorane, [bis (trimethylsilyl) amino] bis (t
-Butylimino) phosphorane, [bis (t-butyl) amino] bis (t-butylimino) phosphorane, [bis (t-butyl) amino] bis (trimethylsilylimino) phosphorane, [bis (t-butyl) amino] (t-
Butylimino) (trimethylsilylimino) phosphorane, (t-butylimino) (trimethylsilylimino)
[(T-Butyl) (trimethylsilyl) amino] phosphorane, [(t-butyl) (trimethylsilyl) amino]
Bis (t-butylimino) phosphorane, [bis (t-butylimino)] (diisopropylamino) phosphorane,
(T-Butylimino) (trimethylsilylimino) (diisopropylamino) phosphorane, (t-butylimino) (trimethylsilylimino) (isopropylamino) (trimethylsilylamino) phosphorane, (t-butylamino) (isopropylamino) bis (trimethylsilylimino) phosphorane , (T-butylamino) (isopropylamino) bis (t-butylimino) phosphorane, (t-butylamino) (isopropylamino) (t
-Butylimino) (trimethylsilylimino) phosphorane, [bis (t-butylimino)] (isopropylamino) (trimethylsilylamino) phosphorane, (2,
2,6,6-tetramethylpiperidideamino) (t-butylimino) (trimethylsilylimino) phosphorane,
(2,2,6,6-tetramethylpiperidide amino) bis (t-butylimino) phosphorane and the like can be mentioned. Of these, [bis (trimethylsilyl) amino] (t-butylimino) (trimethylsilylimino) is preferable.
Phosphorane, [bis (trimethylsilyl) amino] bis (t-butylimino) phosphorane, (t-butylimino) (trimethylsilylimino) [(t-butyl) (trimethylsilyl) amino] phosphorane are used. For example, these compounds are described by Edgar Niecke et
al. Chem. Ber. , 115 volumes, 185 (1
It is possible to synthesize in 982).

Examples of the electron-donating compound include α-olefins, α, ω-dienes, ethers, esters, carboxylic acid anhydrides, carboxylic acids, alcohols, ketones, amines, amides, silanes and nitriles. And aldehydes, alcoholates, thioethers and thioesters. Of these, α-olefins, α, ω
-Dienes, ethers and esters are preferably used.

The α-olefins have 3 to 20 carbon atoms.
Α-olefins are preferred, and specifically, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-nonene, 1-decene, 3-methyl-1-pentene, 4-methyl- 1-pentene etc. are mentioned.
As the α, ω-dienes, α, ω-dienes which may have a branch having 5 to 20 carbon atoms are preferable, and specifically,
4-pentadiene, 1,5-hexadiene, 1,6-heptadiene, 1,7-octadiene, 1,8-nonadiene, 1,9-decadiene, 2-methyl-1,4-pentadiene, 2-methyl-1, Examples thereof include 5-hexadiene and 3-methyl-1,5-hexadiene.

As the ethers, ethers having an alkyl group, an aryl group, a benzyl group, a vinyl group or an allyl group having 1 to 30 carbon atoms are preferable, and specifically, dimethyl ether, diethyl ether, dipropyl ether, dibutyl ether, Diisoamyl ether, methyl ethyl ether, methyl propyl ether, methyl amyl ether, ethyl propyl ether, ethyl butyl ether,
Examples thereof include ethyl amyl ether, methyl vinyl ether, ethyl allyl ether, diphenyl ether, benzyl ether, naphthyl ether, anisole, ethylene oxide, propylene oxide, tetrahydrofuran, tetrahydropyran and dioxane.

As the esters, esters having 2 to 20 carbon atoms are preferable, and specifically, butyl formate, ethyl acetate, isobutyl isoacetate, propyl bivalate, isobutyl pivalate, ethyl acrylate, methyl methacrylate, methacrylic acid. Ethyl, butyl methacrylate, isobutyl methacrylate, diethyl malonate, diisobutyl malonate, diethyl succinate, dibutyl succinate, diisobutyl succinate, diethyl glutarate, dibutyl glutarate, diisobutyl glutarate, diisobutyl adipate, dibutyl sebacate, Diethyl maleate, dibutyl maleate, diisobutyl maleate, monomethyl fumarate, diethyl fumarate, diisobutyl fumarate, diethyl tartrate, dibutyl tartrate, diisobutyl tartrate,
Ethyl cyclohexanecarboxylate, methyl benzoate, ethyl benzoate, phenyl benzoate, methyl p-toluate, p-tertiary butyl ethyl benzoate, ethyl p-anisate, ethyl α-naphthoate, α-isobutyl naphthoate. , Ethyl cinnamate, monomethyl phthalate, monobutyl phthalate, dibutyl phthalate, diisobutyric acid phthalate, dihexyl phthalate, dioctyl phthalate, di2-ethylhexyl phthalate, diallyl phthalate, diphenyl phthalate, diethyl isophthalate, Diisobutyl isophthalate, diethyl terephthalate, dibutyl terephthalate, diethyl naphthalate, dibutyl naphthalate, triethyl trimellitate, tributyl trimellitate, tetramethyl pyromelliticate, tetraethyl pyromelliticate, tetrabutyl pyromelliticate, etc. Is mentioned. Two or more kinds of these electron donating compounds can be used.

Examples of the reducing agent include hydrogen, metal hydrides, organic metal compounds such as alkylaluminum, alkylmagnesium, alkylzinc, and alkyllithium. The organometallic compound contains at least one alkyl group having 1 to 10 carbon atoms, and the remaining valence (if any) of the organometallic compound is a hydrogen atom, a halogen atom,
Hydrocarbyloxy group (hydrocarbyl group has 1 carbon atom
-10), or the metal through an oxygen atom (e.g. in the case of methylalumoxane -O-Al (CH ₃₎
-) And others are preferable, and specifically, trimethylaluminum, triethylaluminum,
Trialkylaluminum such as tripropylaluminum, triisopropylaluminum, tri-n-butylaluminum, triiso-butylaluminum, tripentylaluminum, trihexylaluminum, trioctylaluminum, tridecylaluminum, tri-2-ethylhexylaluminum, dimethylaluminum chloride. Dialkyl aluminum halides such as dimethyl aluminum bromide, diethyl aluminum chloride, diethyl aluminum bromide, diisopropyl aluminum chloride and diisobutyl aluminum chloride, methyl aluminum sesquichloride, ethyl aluminum sesquichloride, isopropyl aluminum sesquichloride, butyl aluminum sesquichloride,
Alkylaluminum sesquihalides such as ethylaluminum sesquibromide, methylaluminum dichloride, ethylaluminum dichloride, isopropylaluminum dichloride, alkylaluminium dihalides such as ethylaluminum dibromide, methylalumoxane, ethyl n-butylmagnesium, n-butylsec.
-Butyl magnesium, diethyl zinc, n-butyl lithium, etc. are also mentioned.

The catalyst is added as a solid or dissolved in a solvent. In the polymerization method of the present invention, when a 0-valent transition metal compound is used as the Group VIII transition metal compound during the polymerization, it is preferable to polymerize with an electron-donating compound, and a divalent transition metal compound is used. When used, it is preferable to polymerize using a reducing agent. The transition metal compound, the compound of the general formula (I), the reducing agent and the electron donating compound may be added in any order, but when a zero-valent transition metal compound is used, the transition metal compound, the compound of the general formula (I) and the electron The order of the donor compound is preferable, and when the divalent transition metal compound is used, the order of the transition metal compound, the compound of the general formula (I) and the reducing agent is preferable. The use ratio is preferably transition metal compound: compound of general formula (I) = 1: 1-100, transition metal compound: reducing agent = 1: 1-100.

The length and number of branches of the polymerized polymer are described, for example, in Takao Usami et al. Macro
Molecules, Volume 20, 1557, (1987)
Can be confirmed by ¹³ C-NMR, IR and GPC. Ethylene homopolymerization or copolymerization using the catalyst according to the present invention can be liquid phase polymerization or gas phase polymerization,
Wide temperature range -78 to 200 ° C, preferably 0 to 80
C, wide pressure range 1-100K / G, preferably 5-5
It can be polymerized at 0K / G. In the case of liquid phase polymerization, it is preferable to use an inert solvent as the solvent, and any inert solvent can be used as long as it is commonly used in this technical field. In particular, a C _{4 to} C ₁₀ aromatic hydrocarbon or halogenated Hydrocarbons can be used. More specifically, pentane, hexaneoctane, decane, cyclohexane, benzene, toluene, xylene, chlorobenzene and the like can be mentioned.

By using the catalyst of the present invention, it is possible to provide a high molecular weight ethylene polymer having a methyl branch and a branch having a side chain length of C ₆ or more in a high yield.

[0020]

EXAMPLES The present invention will now be described in more detail with reference to examples, but the present invention is not limited to these examples. ¹³ C-NMR uses JEOL FX90Q and o-
The polymer dissolved in dichlorobenzene (+ C ₆ D ₆ ) was measured at 135 ° C. IR is JASCO FT / IR-5
It measured using 300. Differential scanning calorimeter (DSC)
Was measured using DSC-7,7500. Gel Permeation Chromatography (GPC) is Water
The polymer dissolved in 1,2,4-trichlorobenzene was measured at 140 ° C. using s 150C-GPC.

The presence of the short-chain branch and the branch having a side chain length of C ₆ or more in the polyethylene produced by the present invention is ¹³ C-N.
Confirmed by MR, its attribution and calculation of the number of branches in 1000 carbon atoms are described in Takao Usami et al. ，
Macromolecules, Volume 20, 1557 (1
987), and performed using ¹³ C-NMR, IR and GPC.

[0022]

Example 1 A stainless steel autoclave having an internal volume of 1.5 liter was sufficiently replaced with nitrogen, and 450 ml of dry toluene was added. A solution of 1.0 mmol of bis (acetylacetonato) nickel (II) in 25 ml of dry toluene and 2.5 mmol of [bis (trimethylsilyl) amino] (t-butylimino) (trimethylsilylimino) phosphorane were added to 25 ml of the solution. The solution dissolved in dry toluene was added to the autoclave. 8.0 mmol of triisobutylaluminum was added to the mixed solution, and then the internal temperature was adjusted to 0 ° C., and then ethylene was introduced to adjust the internal pressure to 10 kg / cm ² G to carry out polymerization for 8 hours. After completion of the polymerization, unreacted ethylene was removed, the reaction mixture was poured into hydrochloric acid-methanol, the precipitate was filtered off, and dried under reduced pressure for 5 hours to obtain 105 g of a polymer. The weight average molecular weight (Mw) was 412,000 and the number average molecular weight (Mn) was 228,000. The melting point (Tm) determined by DSC was 102.4 ° C. The ¹³ C-NMR spectrum of the obtained polymer is shown in FIG. The numbers of methyl branches and branches having a side chain length of C ₆ or more in the polymer were 15.8 and 13.9, respectively, per 1000 carbon atoms.

[0023]

[Example 2] The result of the same polymerization reaction as in Example 1 except that the polymerization time was 3 hours instead of 8 hours, was 39 g.
A polymer of The Mw of the obtained polymer was 9320.
0, Mn was 51500, and Tm was 92.3 ° C. The numbers of methyl branches and branches having a side chain length of C ₆ or more in the polymer were 16.7 and 15.6, respectively, per 1000 carbon atoms.

[0024]

Example 3 As a result of carrying out the same polymerization reaction as in Example 2 except that the polymerization temperature was 40 ° C. instead of 0 ° C., 42 g of a polymer was obtained. The Mw of the obtained polymer was 4700.
0, Mn was 23400, and Tm was 77.8 ° C. The numbers of methyl branches and branches having a side chain length of C ₆ or more in the polymer were 11.6 and 14.5 per 1000 carbon atoms, respectively.

[0025]

Comparative Example 1 [bis (trimethylsilyl) amino] (t
-Butylimino) (trimethylsilylimino) phosphorane was replaced by [bis (trimethylsilyl) amino] bis (trimethylsilylimino) phosphorane in the same manner as in Example 1 to obtain 86 g of a polymer. The Mw of the obtained polymer was 255,000,
Mn was 147,000 and Tm was 90.4 ° C. The numbers of methyl branches and branches having a side chain length of C ₆ or more in the polymer were 17.6 and 9.6, respectively, per 1000 carbon atoms.

[0026]

Comparative Example 2 [bis (trimethylsilyl) amino] (t
-Butylimino) (trimethylsilylimino) phosphorane was replaced by [bis (trimethylsilyl) amino] bis (trimethylsilylimino) phosphorane in the same manner as in Example 2 to obtain 30 g of a polymer. Mw of the obtained polymer was 63900, M
n was 38700 and Tm was 99.4 ° C. The numbers of methyl branches and branches having a side chain length of C ₆ or more in the polymer were 14.7 and 7.4, respectively, per 1000 carbon atoms.

[0027]

Comparative Example 3 [bis (trimethylsilyl) amino] (t
-Butylimino) (trimethylsilylimino) phosphorane was replaced by [bis (trimethylsilyl) amino] bis (trimethylsilylimino) phosphorane, and the same polymerization reaction as in Example 3 was carried out. As a result, 26 g of a polymer was obtained. The Mw of the obtained polymer was 38500, M
n was 19600 and Tm was 75.9 ° C. The numbers of methyl branches and branches having a side chain length of C ₆ or more in the polymer were 13.5 and 8.9, respectively, per 1000 carbon atoms.

[0028]

Example 4 A stainless steel autoclave having an internal volume of 1.5 liter was sufficiently replaced with nitrogen, and 450 ml of dry toluene was added. A solution obtained by dissolving 1.0 mmol of bis (1,5-cyclooctadiene) nickel (0) in 25 ml of dry toluene and 1.0 mmol of bis (trimethylsilyl) amino] (t-butylimino) (trimethylsilylimino) phosphorane were added thereto. A solution of 25 milliliters of dry toluene was added to the autoclave. 1-hexene 3 in the mixed solution
After adding 2.5 ml, the internal temperature was adjusted to 20 ° C., and then ethylene was introduced to adjust the internal pressure to 10 kg / cm ² G. 3
Polymerization was carried out for a time. After completion of the polymerization, unreacted ethylene was removed, the reaction mixture was poured into hydrochloric acid-methanol, the precipitate was filtered off, and dried under reduced pressure for 5 hours to obtain 67 g of a polymer.
Mw 31500, Mn 12100, Tm 90.2
It was ℃. The number of methyl branches in the polymer and the number of branches having a side chain length of C ₆ or more are 11.0 per 1000 carbon atoms, respectively.
The number was 11.7.

[0029]

Example 5 As a result of carrying out the same polymerization reaction as in Example 4 except that 5 ml of ether was added as an electron-donating compound, 94 g of a polymer was obtained. The obtained polymer Mw is 45600, Mn is 21500, and Tm is 91.1.
It was ℃. The number of methyl branches and the number of branches having a side chain length of C ₆ or more in the polymer are each 13.7 per 1000 carbon atoms.
The number was 13.2.

[0030]

Example 6 As a result of carrying out the same polymerization reaction as in Example 4 except that 10.0 mmol of phenyl benzoate was added as an electron-donating compound, 89 g of a polymer was obtained. The polymer obtained had Mw of 43000, Mn of 18500, and T.
m was 94.7 ° C. The numbers of methyl branches and branches having a side chain length of C ₆ or more in the polymer were 11.3 and 12.8 per 1000 carbon atoms, respectively.

[0031]

Comparative Example 4 [bis (trimethylsilyl) amino] (t
-Butylimino) (trimethylsilylimino) phosphorane was replaced by [bis (trimethylsilyl) amino] bis (trimethylsilylimino) phosphorane in the same manner as in Example 4 to obtain 66 g of a polymer. Mw of the obtained polymer was 20,900, M
n was 8200 and Tm was 91.5 ° C. The numbers of methyl branches and branches having a side chain length of C ₆ or more in the polymer were 7.5 and 14.6, respectively, per 1000 carbon atoms.

[0032]

Comparative Example 5 [bis (trimethylsilyl) amino] (t
-Butylimino) (trimethylsilylimino) phosphorane was replaced by [bis (trimethylsilyl) amino] bis (trimethylsilylimino) phosphorane in the same manner as in Example 5 to obtain 92 g of a polymer. The Mw of the obtained polymer was 29200, M
n was 11200 and Tm was 93.3 ° C. The numbers of methyl branches and branches having a side chain length of C ₆ or more in the polymer were 8.6 and 16.3 per 1000 carbon atoms, respectively.

[0033]

Comparative Example 6 [bis (trimethylsilyl) amino] (t
-Butylimino) (trimethylsilylimino) phosphorane was replaced by [bis (trimethylsilyl) amino] bis (trimethylsilylimino) phosphorane in the same manner as in Example 6 to obtain 87 g of a polymer. The Mw of the obtained polymer was 27300, M
n was 12200 and Tm was 95.1 ° C. The numbers of methyl branches and branches having a side chain length of C ₆ or more in the polymer were 8.3 and 15.9, respectively, per 1000 carbon atoms.

[0034]

INDUSTRIAL APPLICABILITY The catalyst of the present invention can provide a high molecular weight ethylene polymer having a methyl branch and a branch having a side chain length of C ₆ or more, which cannot be obtained by a conventional catalyst, in a high yield.

[Brief description of drawings]

FIG. 1 ^{13 of} polyethylene obtained in Example 1 of the present invention
It is a C-NMR spectrum figure.

Claims (6)

[Claims] 1. A catalyst component for ethylene polymerization comprising a Group VIII transition metal compound and the following general formula (I). [Chemical 1] 2. The catalyst component for ethylene polymerization according to claim 1, wherein the Group VIII transition metal compound is a nickel compound. 3. A method for polymerizing ethylene, which comprises polymerizing ethylene in the presence of the catalyst component for ethylene polymerization according to claim 1 in polymerizing ethylene. 4. When polymerizing ethylene, the catalyst component for ethylene polymerization according to claim 1 and a reducing agent and / or
The ethylene polymerization method according to claim 3, wherein ethylene is polymerized in the presence of an electron donating compound. 5. The ethylene polymerization method according to claim 3, wherein the Group VIII transition metal compound is a divalent nickel compound and is carried out in the presence of a reducing agent. 6. The ethylene polymerization method according to claim 3, wherein the Group VIII transition metal compound is a zero-valent nickel compound and is carried out in the presence of an electron donating compound.