JPS6286007A - Production of ethylene polymer - Google Patents

Abstract

PURPOSE:To obtain the titled polymer of excellent mechanical strength in good efficiency, by (co)polymerizing ethylene in the presence of a catalyst comprising a specified transition metal compound component and an organometallic compound component. CONSTITUTION:A catalyst is obtained by combining a transition metal compound component obtained by contacting 1mol of at least one Cr compound selected from among a chromium chelate compound of the formula of Cr(acac)3 (wherein acac is acetylacetonate), a chromium pi-complex of the formula of (cp)2Cr (wherein cp is cyclopentadienyl) and a chromium aryl compound of the formula of (C6H5)2Cr with 1-100mol of a Mg compound or a Mn compound (e.g., ethylbutylmagnesium) at 0-200 deg.C for 5-60min with a halogen-containing alkylaluminum compound (e.g., dimethylaluminum monochloride) as an organometallic component. Ethylene is polymerized or copolymerized with other olefins at 0-150 deg.C and a pressure of normal pressure to 50kg/cm<2> in the presence of said catalyst.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method for producing ethylene polymers, and more specifically, the present invention relates to a method for producing ethylene polymers, and more specifically, the present invention relates to a method for producing ethylene polymers using a catalyst containing a specific transition metal compound component and an organometallic compound component as main components. The present invention relates to a method for efficiently producing a polymer.

[Prior art and problems to be solved by the invention] Conventionally, when polymerizing ethylene or copolymerizing ethylene with other α-olefins, a catalyst consisting of a combination of chromium acetylacetonate and an organoaluminum compound has been used. It is known that
No. 6132).

However, catalysts made of a combination of these two components have a problem in that they do not have sufficient ethylene polymerization activity.

[Means for Solving the Problems] Therefore, as a result of various studies in order to solve the problems of the prior art, the present inventors found that a chromium chelate compound, a chromium π- By using a contact treatment product of at least one chromium compound selected from the group consisting of complexes and chromaryl compounds and a magnesium compound or a manganese compound,
It was discovered that the polymerization activity of ethylene was significantly improved, and the present invention was completed.

That is, the present invention produces an ethylene polymer by polymerizing ethylene or copolymerizing ethylene and other α-olefins using a catalyst whose main components are (A) a transition metal compound component and (B) an organometallic compound component. In the method (
A) Contacting the IB transfer metal compound component with (i) at least one chromium compound selected from the group consisting of a chromium chelate compound, a chromium π-complex, and a chromium aryl compound and (i) a magnesium compound or a manganese compound. In addition to using the treated product, (B) a halogen-containing alkyl aluminum compound is used as the organometallic compound component.
The present invention provides a method for producing an ethylene polymer characterized by the following.

As mentioned above, the transition metal compound component (A) of the catalyst used in the method of the present invention is at least one chromium compound selected from the group consisting of (i) a chromium chelate compound, a chromium π-complex, and a chromium aryl compound. and (i)
It is a contact-treated product with a magnesium compound or a manganese compound.

The chromium chelate compound specifically has the formula 0r (acac
) Chromium trisacetylacetonate represented by 3,
Chromium tris(2-methyl-1,3-butanedioate) represented by Or(mbd)3.

Examples include chromtris(1,3-butanedioate) represented by 0r(bd)3, where (acac
) indicates an acetylacetonate group, and chromium trisacetylacetonate is represented by the structural formula. In addition, (mbd) represents a 2-methyl-1,3-butanedioate group, and chromium tris (
2-methyl-1,3-butanedione) is represented by the structural formula. Furthermore, (bd) represents a 1,3-butanedioate group, and chromium tris(1,3-butanedioate) is represented by the following structural formula.

As a chromium π-complex, (cp)? Or ((cp
) represents a cyclopentadienyl group), (C6H6)-Cr
Bisbenzenechromium, (2C6H5) (
Diphenylbenzene chromium represented by C6H6)Or, dihexamethylbenzene chromium 9 represented by the formula H
3 π-cyclopentadienylbromochromium acetylacetate represented by the formula 9 π-cyclopentadienyl(benzene)chromium represented by the formula 2 π-cyclopentadienyl-π-cycloheptagenylchromium represented by the formula 2 Examples include aromatic ring π-complexes such as, π-allyl 8 complexes such as tris(η-allyl)chromium, and tetrakis(η-allyl)chromium.

Furthermore, examples of the chromaryl compound include diphenylchromium, tetraphenyltristetrahydrofuran, and the like.

Further, (i) the above (i) is subjected to contact treatment with a chromium compound.
The compound is a magnesium compound or a manganese compound. There are various magnesium compounds or manganese compounds, such as magnesium or manganese carboxylates, and organic phosphorus-containing compounds.

Specifically, these magnesium and manganese salts have the general formula Mg(R' C00)2 t ? , 4t M
g (RICOO) ] Magnesium carboxylate represented by general formula Mn(R1000)2 or Mn(RICO
O)X [wherein R1 and X are the same as above. ] is manganese carboxylate.

In the above general formulas representing magnesium carboxylate and manganese carboxylate, R1 is as described above, but is preferably an aliphatic alkyl group having a6 or more carbon atoms, particularly preferably an aliphatic alkyl group having 8 or more carbon atoms. , specifically the hexyl group.

Examples include heptyl group, octyl group, 2-ethylhexyl group, nonyl group, decyl group, lauryl group, myristyl group, heptadecyl group, and stearyl group. Further, unsaturated alkyl groups such as an oleyl group can be mentioned.

There are various organic phosphorus-containing compounds of magnesium or manganese, and there are no particular limitations, but those obtained by reacting an organic magnesium compound or an organic manganese compound with a hydrogen-containing phosphorus compound are preferable. Here, the organic magnesium compound or organic manganese compound has the general formula R2R3M [wherein R2, R3
each represents an alkyl group or an aryl group having 1 to 10 carbon atoms, and M represents magnesium or manganese. ] or R7MX [wherein R2 represents an alkyl group or an aryl group having 1 to 10 carbon atoms,
M represents magnesium or manganese, and X represents a halogen atom. ] Compounds represented by these formulas can be cited as preferred. Specific examples include ethylbutylmagnesium, dibutylmagnesium, diethylmagnesium, dihexylmagnesium, dimethylmanganese, diphenylmanganese, ethylmagnesium chloride, ethylmagnesium iodide, and methylmanganese iodide.

In addition, 'XI with these organoaluminum and organozinc
Salt can also be used.

On the other hand, hydrogen-containing phosphorus compounds include alkyl or arylphosphines such as methylphosphine, ethylphosphine, propylphosphine, butylphosphine, and phenylphosphine, and dialkyl or diarylphosphines such as diethylphosphine, dipropylphosphine, dibutylphosphine, and diphenylphosphine. , alkyl or aryl phosphonic acids such as ethyl phosphonic acid, propyl phosphonic acid, dialkyl or diarylphosphinic acids such as diethyl phosphinic acid, dipropylphosphinic acid, dibutyl phosphinic acid, didodecyl phosphinic acid, diphenyl phosphine, phosphorous acid methyl ester , phosphite butyl ester, phosphite dimethyl ester, phosphite dipropyl ester, phosphite dibutyl ester, phosphite dodecyl ester, phosphite dilauryl ester, phosphite dioleyl ester, diphenyl phosphite Examples include phosphorous esters such as esters, phosphoric acid esters such as ethyl phosphate, propyl phosphate, dipropyl phosphate, dibutyl phosphate, dioctyl phosphate, and didodecyl phosphate.

There are no particular restrictions on the contact treatment of the above-mentioned (i) chromium compound and (i) magnesium or manganese compound, but usually each is added to an appropriate solvent and mixed, and the mixture is heated at a temperature of O to 200°C, preferably. The mixture may be stirred at about 30 to 100°C for about 5 to 60 minutes. Mataokaki (i)
The mixing ratio of the compounds between (ii) and (ii) varies depending on the type of compound used, but in general, the activity of the catalyst increases as a larger amount of (ii) magnesium or mankan compound is used relative to (i) chromium compound. Have sex. in particular,(
D chromium compound, (i7) magnesium or manganese compound 1 to 100 times mole, preferably 20 to
It may be appropriately determined within a 50-fold molar range.

In the method of the present invention, the thus obtained contact-treated product of the (i) chromium compound and (0) magnesium or manganese compound is referred to as (A) J&, and the halogen-containing alkylaluminum compound is referred to as (B) component. and these (A)
, (B) A catalyst containing both components as main components is used. Examples of the halogen-containing alkyl aluminum compound which is component CB) include dimethylaluminum monochloride, diethylaluminum monochloride, diisopropylaluminum monochloride, and diisobutylaluminum monochloride.

Dialkylaluminum monohalides such as dioctylaluminum monochloride, monoalkylaluminum cybarides such as methylaluminum dichloride, ethylaluminum dichloride, isobutylaluminum dichloride, and alkylaluminum sesquichlorides such as methylaluminum sesquichloride, ethylaluminum sesquichloride, and ethylaluminum sesquipromide. Examples include halides and mixtures thereof, as well as mixtures thereof with trialkylaluminum. Among these, the above-mentioned dialkyl aluminum monohalides are particularly preferred.

In the method of the present invention, ethylene is polymerized or ethylene is copolymerized with other α-olefins using a catalyst containing the above-mentioned components (A) and (B) as main components, but the polymerization method and conditions are particularly limited. Instead, any of solution polymerization, suspension polymerization, gas phase polymerization, etc. is possible, and both continuous polymerization and discontinuous polymerization are possible.

In this case, the polymerization solvent is an aliphatic hydrocarbon.

Alicyclic hydrocarbons, aromatic hydrocarbons, and halogenated hydrocarbons are used. Polymerization conditions include reaction temperature of 0 to 150°.
C1 is preferably 20 to 80°C, and the reaction pressure is normal pressure to 50 kg/cm/G, preferably normal pressure to 20 kg/a
ml'G.

In addition, there are no particular restrictions on the catalyst #II&, and the molar ratio of aluminum atoms in component (B) to chromium atoms in component (A) is usually 1 to 5000 C, l, u.
f preferably from 5 to 1000 (molar ratio), and the above (
In component A), the ratio of magnesium atoms or manganese atoms to chromium atoms is 1 to 100 (molar ratio), preferably 20 to 50 (molar ratio).

For example, in the case of solution polymerization or suspension polymerization, the amount of the catalyst component added is: o,
ooi~5.0 mmol/p, preferably 0.005
~1 mmol/1. Molecular weight adjustment during polymerization can be carried out by known means, for example, by temperature control wJ'8.

In the method of the present invention, ethylene can be homopolymerized, and ethylene and other α-olefins (eg, propylene, butene-1, hexene-1, octene-1, etc.) can also be copolymerized.

Effects of the Invention] According to the method of the present invention, the activity of the catalyst used is significantly higher than that of conventional chromium-based catalysts, and the resulting ethylene polymer provides injection molded articles with high mechanical strength.

Therefore, according to the method of the present invention, an ethylene polymer having excellent mechanical strength can be produced very efficiently.

[Example code] Next, the present invention will be explained in more detail with reference to Examples.

Example 1 (1) Preparation of (i) and (ii) of catalyst component (A) 2.1 g (6 mmol) of chromium trisacetylacetonate was dissolved in 200 mβ of toluene to obtain catalyst component (1).

■ Contents: 5 heptane in a 200mA+ flask.
0 mj) and 6.45 g (20 mmol) of di-2-ethylhexyl phosphate, and then 30 m of a hebutane solution containing 1059 mol of ethylbutylmagnesium!
was added dropwise over 20 minutes at room temperature.

Next, this was heated and reacted for 3 hours under reflux of heptane, and then the heptane was distilled off and 100 mj) of toluene was added to obtain the catalyst component (i).

(λ) Polymerization of ethylene Toluene (400 + sj) was placed in an autoclave with an internal volume of 1 replaced with argon, and 0.008 mmol of the catalyst component (i) obtained in (1) above as a chromium atom and the catalyst component (i ) as a magnesium atom.
32 mmol was added and stirred and mixed at 40'O for 20 minutes (catalyst component (A)).

Next, 7 ml of diethylaluminum monochloride as the catalyst component (B) was added to this mixed solution, and then ethylene was continuously introduced, and the pressure was increased to 8 kg/
The polymerization reaction was carried out for 1 hour while maintaining the temperature at c+s2G. As a result, the yield of polyethylene was 85.4 g, and the catalyst activity was 205 kg/g-cr.

Example 2 The same operation as in (2) of Example 1 was carried out except that the amount of catalyst component (ii) used in (2) of Example 1 was 0.64 mmol in terms of magnesium atoms. As a result, the yield of polyethylene was 92 g, and the catalytic activity was 2.
It was 21 kg/g-cr.

Comparative Example 1 In (2) of Example 1, the same operation as in (2) of Example 1 was performed except that catalyst component (ii) was not used. As a result, the yield of polyethylene was 0.32 g, and the catalyst activity was 0.77 kg/g-cr.

Example 3 The same operation as in (2) of Example 1 was carried out, except that the catalyst component (B) in (2) was replaced with diethylaluminum chloride and 7 ml of diisobutylaluminum monochloride was used. As a result, the yield of polyethylene was 35.1g,
Catalytic activity was 84.4 kg/g-Or.

Example 4 The same procedure was carried out as in (2) of Example 1, except that a mixture of 3.5 mmol of triethylaluminum and 3.5 mmol of diethylaluminium monochloride was used instead of diethylaluminum monochloride as the catalyst component (B). The same operation as in Example 1 (2) was performed. As a result,
The yield of polyethylene was 48.8 g, and the catalytic activity was 1
It was 17 kg/g-Or.

Example 5 In (2) of Example 1, instead of catalyst component (11),
The same operation as in Example 1 (2) was performed except that 0.19 g (0.32 mmol) of magnesium stearate was used. As a result, the yield of polyethylene was 27.
There is 9g of te, and the catalyst activity is 87. It was 1 kg/g-cr.

Example 6 In (2) of Example 1, instead of catalyst component (ii),
Manganese stearate O. The same operation as in Example 1 (2) was performed except that 19Ei g (0.32 mmol) was used. As a result, the yield of polyethylene was 20
．． There was 4g of te, and the catalyst activity was 49kg/g·cr.

Example 7 (1) Preparation of catalyst component (A) (i) In an argon-substituted flask with an internal volume of 200 mg, 1.22 g of biscyclopentadienylchromium (8,
7 mmol) was dissolved in 200 ml of toluene to obtain catalyst component (A) (1).

(2) As (i) of the ethylene polymerization catalyst component (A), use (i) of the catalyst component (A) prepared in (1) above as a chromium atom, o, oos
The same procedure as in Example 1 (2) was carried out except that millimole was used. As a result, the yield of polyethylene was 22 g, and the catalyst activity was 52.9 kg/g-Or.

Comparative Example 7 In (2) of Example 7, (ii) of catalyst component (A)
The same procedure as in Example 7 (2) was conducted except that the magnesium compound was not used. As a result, the yield of polyethylene was 0.77g, and the catalyst activity was 1.85kg/g.
-cr.

Example 8 (1) Preparation of (i) of catalyst component (A) In an argon-substituted flask with contents t & 200 ml, 1.51 g (7.33 mmol) of diphenylchromium was dissolved in 200 mp of toluene to prepare catalyst component (A).
A) (i) was obtained.

(2) As (1) of the ethylene polymerization catalyst component (A), use (i) of the catalyst component (A) prepared in (1) above as a chromium atom, o, oos
The same procedure as in Example 1 (2) was carried out except that mmol was used. As a result, the yield of polyethylene was 26 g, and the catalyst activity was 82.5 kg/g-cr.

Comparative Example 3 The same procedure as in Example 8 (2) was carried out except that the magnesium compound of catalyst component (A) (i) was not used in Example 8 (2). As a result, the yield of polyethylene was 0.42 g, and the catalyst activity was 1.0 kg/g-c.
It was r.

Claims (7)

[Claims] (1) A method for producing ethylene polymers by polymerizing ethylene or copolymerizing ethylene and other α-olefins using a catalyst whose main components are (A) a transition metal compound component and (B) an organometallic compound component. (A) as a transition metal compound component (i) contacting at least one chromium compound selected from the group consisting of chromium chelate compounds, chromium π-complexes and chromaryl compounds and (ii) a magnesium compound or a manganese compound; A method for producing an ethylene polymer, comprising using a treated product and (B) a halogen-containing alkyl aluminum compound as the organometallic compound component. (2) The chromium chelate compound has the formula Cr(acac)_
3 [Wherein, acac represents an acetylacetonate group. ] The manufacturing method according to claim 1, which is trisacetylacetonatochromium represented by the following. (3) The chromium π-complex has the formula (cp)_2Cr [wherein,
2. The production method according to claim 1, wherein cp represents a cyclopentadienyl group. (4) The chromaryl compound has the formula (C_6H_5)_
The manufacturing method according to claim 1, which is diphenylchromium represented by 2Cr. (5) The production method according to claim 1, wherein the magnesium compound is a magnesium carboxylate or a magnesium organic phosphorus-containing compound. (6) The production method according to claim 1, wherein the manganese compound is a manganese carboxylate or a manganese organic phosphorus-containing compound. (7) The production method according to claim 1, wherein the halogen-containing alkyl aluminum compound is a dialkyl aluminum monohalide.