JPS61130313A - Production of polyolefin - Google Patents

Abstract

PURPOSE:To improve the catalytic activity, by using an organoaluminum catalyst component obtained by modifying an organoaluminum compound with an ether, an ester or a ketone in the presence of an olefin by using a vanadium catalyst component and an organoaluminum component. CONSTITUTION:An organoaluminum compound such as an alkylaluminum of formula I (wherein R<1> is a 1-10C alkyl, X is a halogen and n is 1-3), e.g., triethylaluminum, or an alkoxyaluminum of formula II (wherein R<2> and R<3> are each a 1-10C alkyl and m is 0-2), e.g., diethylaluminum ethoxide, is modified with an ether (e.g., diethyl ether), an ester (e.g., benzyl benzoate) or a ketone. An olefin is (co)polymerized by using a catalyst formed by combining the obtained organoaluminum catalyst with a vanadium catalyst component (e.g., VCl4).

Description

[Detailed description of the invention] The present invention relates to a method for producing polyolefins.

BACKGROUND ART It has been known to use a vanadium-based catalyst made of a combination of a vanadium compound and an organoaluminum in the production of polyolefins by polymerizing olefins. Although this vanadium-based catalyst has a high initial activity and good copolymerizability between olefins, the sustainability of the activity is poor, and various attempts have been made to improve this activity.

For example, a method is known in which the activity of a vanadium compound is improved by treating it with ether (Japanese Unexamined Patent Publication No. 53-197)
-98382).

However, even in this case, the improvement in catalytic activity cannot be said to be sufficient.

Therefore, the present inventors conducted further studies on vanadium-based catalysts in order to solve the above-mentioned conventional drawbacks, and found that the activity was significantly improved by modifying the organoaluminum compound as a promoter with ether, ester, or ketone. It was discovered that the process of removing the catalyst in the polyolefin product could be omitted, and based on this knowledge, the present invention was completed.

That is, in the present invention, when producing a polyolefin by polymerizing or copolymerizing an olefin using a catalyst consisting of a vanadium catalyst component and an organoaluminum catalyst component, the organoaluminum compound is preliminarily treated with an ether, an ester, or a ketone as the organoaluminum catalyst component. The purpose of the present invention is to provide a method for producing a polyolefin, which uses a polyolefin modified by.

The olefin used for polymerization in the present invention is not particularly limited, but ethylene is particularly preferred.

Also, a small amount of propylene and butene-1 relative to ethylene
It is also possible to copolymerize α-olefins such as.

In producing polyolefins by polymerizing or copolymerizing the above olefins, a catalyst consisting of a vanadium catalyst component and an organoaluminum catalyst component is used.

Here, specific examples of vanadium compounds used as vanadium catalyst components include [vanadium oxides such as vCla and VCl3; vanadium oxychlorides such as VOCIs and VOCI□; V(0·n-CJq)*, VO(
OCtHs)z.

Vanadium alkoxides such as VO(0·n-C4Hz)z; cyclopentagenylvanadium derivatives such as dicyclopentadienylvanadium chloride; V (
acac)! Mention may be made of vanadium acetylacetonate compounds such as 1VO(acac)2. In addition, here aacac is an acetylacetonate group,
That is, it represents an acetylacetone ion.

Next, an organoaluminum catalyst component is used as the second component of the catalyst, and in the present invention, as the organoaluminum catalyst component, an organoaluminum compound is pre-contained with ether,
It is characterized by using a substance modified with an ester or a ketone.

Here, as an organoaluminum compound modified with ether, ester or ketone, the general formula % formula % (in the formula, R1 is an alkyl group having 1 to 10 carbon atoms, X is a halogen atom, and n is 1 to 3 (represents a real number).

Examples include alkoxyaluminum or aluminoxane represented by the general formula % (in the formula, R1 and R3 represent an alkyl group having 1 to 10 carbon atoms, and m represents a real number of 0 to 2).

Specific examples of the alkyl aluminum represented by the general formula CI) include trialkylaluminum compounds such as trimethylaluminum, triethylaluminum, triisopropylaluminium, triisobutylaluminum, trioctylaluminum, diethylaluminum monochloride, diethylaluminum monopromide, etc. , dialkylaluminum monohalides such as diethylaluminum monoiodide, diisopropylaluminum monochloride, diisobutylaluminum monochloride, dioctylaluminum monochloride, or methylaluminum sesquichloride, ethylaluminum sesquichloride, ethylaluminum sesquipromide, butylaluminum sesquichloride, etc. Alkylaluminum sesquihalides are preferred, and also mixtures thereof.

Further, specific examples of the alkoxyaluminum represented by the above general formula (II) include alkylaluminum alkoxides such as diethylaluminum ethoxide, diethylaluminum isopropoxide, and diisobutylaluminum ethoxide. Further, as the aluminoxane, an alkyl group-containing aluminoxane produced by a reaction between an alkyl aluminum and water can also be used.

The ether used for modifying the above organoaluminum compound usually has the general formula R'-0-R' (where R4゜R5 is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group, an aryl group, a vinyl group, an aralkyl group) group, alkenyl group, or alkoxyalkyl group, and R4 and R'!1 may be the same or different.) Specifically, diethyl ether, diisoamyl ether , diisopropyl ether, dibutyl ether, diisobutyl ether, moro-amyl ether, diisoamyl ether, dihexyl ether, dioctyl ether, dicyclohexyl ether, diphenyl ether, dibenzyl ether, anisole,
Examples include ethylene glycol dibutyl ether.

Further, ethers include cyclic ethers, specifically propylene oxide, trimethylene oxide, tetrahydrofuran, tetrahydropyran, dioxane,
Examples include trioxane.

The above ethers include di-n-butyl ether,
It is preferable to use aliphatic ethers such as diethyl ether and diisopropyl ether, and aromatic ethers such as anisole.

Furthermore, esters can also be used to modify the organoaluminum compound. Here, the ester has the general formula % (wherein Rh and R't are alkyl groups having 1 to 20 carbon atoms.

It represents a cycloalkyl group, an aryl group, a vinyl group, an aralkyl group, or an alkenyl group, and Rh and R7 may be the same or different. ), specifically methyl formate.

Methyl acetate, ethyl acetate, vinyl acetate, propyl acetate,
Octyl acetate, cyclohexyl acetate, ethyl propionate, methyl butyrate, ethyl valerate, methyl chloroacetate, ethyl dichloroacetate, ethyl acrylate, methyl methacrylate, ethyl crotonate, ethyl pivalate, dimethyl maleate, ethyl cyclohexanecarboxylate, Methyl benzoate.

Ethyl benzoate, propyl benzoate, butyl benzoate,
Hexyl benzoate, octyl benzoate, cyclohexyl benzoate, phenyl benzoate, benzyl benzoate, methyl toluate, ethyl toluate, amyl toluate,
Ethyl ethyl benzoate.

Methyl anisate, ethyl anisate, ethyl ethoxybenzoate, ethyl p-butoxybenzoate, ethyl 0-chlorobenzoate, ethyl naphthoate, r-butyrolactone, δ-valerolactone, coumarin.

Examples include phthalide and ethylene carbonate.

As the above-mentioned ester, benzoic acid esters such as benzyl benzoate, normal octyl benzoate, and normal hexyl benzoate are particularly preferable.

Furthermore, in the present invention, a ketone can also be used to modify the organoaluminum compound. Here, the ketone is a general formula (wherein R11 and R9 are an alkyl group having 1 to 20 carbon atoms.

Indicates a cycloalkyl group, aryl group, vinyl group, aralkyl group, or alkenyl group, and R8 and R'? may be the same or different. ) or cyclic ketones such as cyclopentanone, cina and hexanone are used. The above ketones include acetone and methyl ethyl ketone.

Ketones having 3 to 15 carbon atoms such as methyl isobutyl ketone, acetophenone, benzophenone, and benzoquinone are preferably used.

The organoaluminum compound is modified by adding the above ether, ester or ketone to the organoaluminum compound in a molar ratio of 0.1 to 50, preferably 0.2 to 20 (molar ratio).

There are no particular restrictions on the denaturation conditions, but usually -50
The reaction may be carried out at a temperature of ~+100°C for 5 to 60 minutes.

In the present invention, a catalyst consisting of an organoaluminum catalyst component and a vanadium catalyst component in which the organoaluminum compound is modified in advance with ether, ester, or ketone is used in the present invention. Here, the catalyst composition is 0.1 to 10 vanadium to aluminum as metal atoms.
00 (molar ratio), preferably 1 to 500 (molar ratio).

Polyolefins are produced by polymerizing or copolymerizing olefins using the catalysts described above.

The polymerization reaction is carried out using a polymerization solvent such as an aliphatic hydrocarbon, an aromatic hydrocarbon, an alicyclic hydrocarbon, or a halogenated hydrocarbon. The polymerization conditions are a reaction temperature of -50 to 2
00°C, preferably -30 to 100°C, and the reaction pressure is normal pressure to 100 kg/Cl1"G, preferably normal pressure to 30 kr/cm"G. Molecular weight adjustment during polymerization may be carried out using hydrogen, alkylzinc, or the like.

In the present invention, since a catalyst consisting of a vanadium catalyst component and an organoaluminum catalyst component obtained by modifying an organoaluminum compound with ether, ester, or ketone is used, the activity of the catalyst is significantly improved, and the polymerization activity, especially the ethylene polymerization activity, is improved. can be improved.

Furthermore, in the present invention, the step of removing the catalyst from the polyolefin product can be omitted.

Therefore, the present invention can be effectively used for producing polyolefins, particularly polyethylene and ethylene copolymers.

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

Example 1 After purging a reaction vessel with an internal volume of 500 m and 12 with argon, 300 tsl of hexane, 0.5 mmol of triethylaluminum as an organoaluminum compound, and 0.5 mmol of di-n-butylnefur as a modifier) were added.
mol was added thereto, and the reaction was carried out for 10 minutes at 50° C. with stirring. Next, 1 kg/kg of ethylene was added to this reaction vessel.
After adding 0.01 mmol of vanadium tetrachloride diluted in hexane as a vanadium catalyst component, ethylene was continuously introduced to maintain a pressure of 2 kg/c+i"G and polymerization was carried out for 3 hours. I did this. The obtained polymer was dried under reduced pressure at 80'C for 2 hours. The yield of polyethylene was 43.0 g, and the catalyst activity was 84.4 kg.
/g vanadium.

Comparative Example 1 The same procedure as in Example 1 was carried out except that the modifier di-n-butyl ether was not used. The yield of polyethylene was 8.1 g, and the catalyst activity was 16.0 kg/g.vanadium.

Example 2 The same procedure as in Example 1 was carried out except that 0.5 mmol of diethyl ether was used instead of di-n-butyl ether as the modifier. The yield of polyethylene was 31.1 g, and the catalytic activity was 61.1
kg/g・vanadium.

Example 3 The same procedure as in Example 1 was carried out except that 0.5 mmol of diisopropyl ether was used instead of di-n-butyl ether as the modifier.

The yield of polyethylene was 19.3 g, and the catalytic activity was 3
The amount was 7.9 kg/g.vanadium.

Example 4 The same procedure as in Example 1 was carried out except that 0.5 mmol of anisole was used instead of di-n-butyl ether as the modifier. The yield of polyethylene was 20.0g, and the catalyst activity was 39.3kg/
g.vanadium.

Example 5 The same procedure as in Example 1 was carried out except that 0.25 mmol of benzyl benzoate was used instead of di-n-butyl ether as the modifier. The yield of polyethylene was 30.9 g, and the catalyst activity was 60.9 g.
The amount of vanadium was 6 kg/g.

Example 6 The same procedure as in Example 1 was carried out except that 0.1 mmol of benzyl benzoate was used instead of di-n-butyl ether as the modifier. The yield of polyethylene was 41.7 g, and the catalyst activity was 81.7 g.
The amount was 9 kg/g.vanadium.

Example 7 The same procedure as in Example 1 was carried out except that 0.25 mmol of n-octyl benzoate was used instead of di-n-butyl ether as the modifier. The yield of polyethylene was 21.5 g, and the catalyst activity was 42.1 kg/g.vanadium.

Example 8 The same procedure as in Example 1 was conducted except that 0.25 mmol of n-hexyl benzoate was used instead of di-n-butyl ether as the modifier. The yield of polyethylene was 15.7 g, and the catalyst activity was 31.0 kg/g.vanadium.

Example 9 The same procedure as in Example 1 was carried out except that 0.1 mmol of diphenyl ketone was used instead of di-n-butyl ether as the modifier. The yield of polyethylene was 17.6 g, and the catalyst activity was 34.6
kg/g・vanadium.

Example 10 Example 1 except that 0.5 mmol of diethylaluminium monochloride was used instead of triethylaluminum as the organoaluminum compound, and 0.1 mmol of diethyl ether was used instead of di-n-butyl ether as the modifier. It was carried out in the same manner as in Example 1. The yield of polyethylene was 33.4 g, and the catalyst activity was 65.0 kg/g.vanadium.

Comparative Example 2 Example 10 was carried out in the same manner as Example 1o except that diethyl ether as a modifier was not used. The yield of polyethylene was 5.0 g, and the tactile activity was 9.8 kg/g.vanadium.

Example 11 In Example 1, 0.5 mmol of diethylaluminum monochloride was used instead of triethylaluminum as the organoaluminum compound, and n-butylvanadate (VO(OCJq)3) 0 was used instead of vanadium tetrachloride as the vanadium compound. The same procedure as in Example 1 was carried out except that .01 mmol was used. The yield of polyethylene is 6.6g, and the catalytic activity is 13k
g/g vanadium.

Comparative Example 3 The same procedure as in Example 11 was carried out except that the modifier di-n-butyl ether was not used. The yield of polyethylene was 3.7 g, and the tactile activity was 7.2 kg/g.vanadium.

Example 12 Hexane 300II11 was placed in a 500II11 reaction vessel purged with argon, and then 0.5 mmol of triethylaluminum and 0.0 mmol of di-n-butyl ether were added.
．． Add 5 mmol and add 1 mmol while stirring at 50°C.
The reaction was carried out for 0 minutes. Next, 0.5 kg of propylene
/ CIl” G, and after propylene is dissolved in hexane and saturated, ethylene is added at 2 kg /
cn ” G, a hexane solution of 0.01 mmol of vanadium tetrachloride was added, and then ethylene was continuously introduced, and polymerization was carried out for 3 hours while keeping the total pressure constant. After the completion of the reaction , the obtained copolymer was heated to 80°C.
It was dried for 2 hours. The yield of the copolymer was 17.5 g, the catalytic activity was 34.4 kg/g vanadium,
The propylene content was 6.0% by weight.

Comparative Example 4 150 ml of heptane and 2.88 mj of tetrahydrofuran were placed in a reaction vessel purged with argon! was added, and a solution of 0.75 m/vanadium tetrachloride in bebutane was added dropwise to this at 25° C. over 20 minutes. After 3 hours of reaction, a modified vanadium catalyst component was obtained. Next, 500ml
300 m/m of hexane and 0.5 mmol of triethylaluminum were placed in a reaction vessel, and ethylene was introduced at 50°C at a rate of 1 kg/cm''G. Then, 0.0025 mmol of the modified vanadium catalyst component was added, and then Ethylene was continuously supplied at a rate of 21 g/cs2G and a polymerization reaction was carried out for 2 hours.As a result,
The yield of polyethylene was 1.9g, and the catalyst activity was 7.
It was 3 kg/g vanadium.

Claims (6)

[Claims] (1) When producing a polyolefin by polymerizing or copolymerizing an olefin using a catalyst consisting of a vanadium catalyst component and an organoaluminum catalyst component, the organoaluminum compound as the organoaluminum catalyst component is modified in advance with ether, ester, or ketone. A method for producing a polyolefin, characterized by using a polyolefin. (2) Claim 1 in which the olefin is ethylene
The method described in section. (3) The organoaluminum compound has the general formula R^1_nAlX_3_-_n (in the formula, R^1 is an alkyl group having 1 to 10 carbon atoms, X is a halogen atom, and n is a real number of 1 to 3). Alkyl aluminum represented by the general formula R^2_m(R^3O)_3_-_mAl (wherein, R^2 and R^3 represent an alkyl group having 1 to 10 carbon atoms, and m represents a real number of 0 to 2. .) The method according to claim 1, wherein the alkoxyaluminum or aluminoxane is represented by: (4) The method according to claim 1, wherein the organoaluminum compound is modified by adding 0.1 to 50 (mole ratio) of ether, ester, or ketone. (5) The method according to claim 1, wherein the ether is any one of di-n-butyl ether, diethyl ether, diisopropyl ether, and anisole. (6) The method according to claim 1, wherein the ester is benzyl benzoate, normal octyl benzoate, or normal hexyl benzoate.