JPS642121B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for polymerizing α-olefin, in particular, polymerizing α-olefin having 3 to 8 carbon atoms using a specific activated titanium catalyst component, an organometallic compound, and an organic acid ester compound,
This invention relates to a method for obtaining highly stereoregular poly-α-olefins with high activity. Conventionally, α-
Methods for stereoregularly polymerizing olefins are known, for example, Japanese Patent Publication No. 1983-34098;
98076, and the method disclosed in Japanese Unexamined Patent Publication No. 53-2580. However, each method has advantages and disadvantages, and no method has yet been developed that satisfies various demands such as high activity, high stereoregularity, high bulk specific gravity, stability of the polymer, and ease of handling of the catalyst. In particular, there is an inverse correlation between the polymerization activity of the catalyst and the stereoregularity of the resulting polymer, and it has so far been extremely difficult to simultaneously maintain both of them at high levels. The present inventors have worked diligently to overcome the drawbacks of the above-mentioned conventional techniques and to develop a method for producing polyα-olefins with high bulk specific gravity while maintaining a high degree of both polymerization activity and stereoregularity of the resulting polymer. I did a lot of research. As a result, they discovered that the object could be achieved by using a specially treated magnesium compound with a titanium component supported thereon as a component of the catalyst, leading to the completion of the present invention. That is, the present invention provides (A) a compound having the general formula Mg(OR ¹ ) ₂ [wherein R ¹ represents an alkyl group having 1 to 5 carbon atoms]. ] to a mixture of magnesium dialkoxide and magnesium chloride, a mixture of the general formula R ³ OH [wherein R ³ represents an alkyl group or cycloalkyl group having a straight chain or side chain having 1 to 10 carbon atoms] . ], then an organic acid ester compound is reacted, and further the general formula TiX ¹ ₄ [in the formula,
X ¹ represents a halogen atom. A solid product obtained by reacting titanium tetrahalide represented by (B) general formula AlR ⁴ _n X ² _3-n [wherein R ⁴ is a carbon number of 1 to
5 alkyl group, m is a real number between 2 and 3, and X ² represents a halogen atom. ] An α-olefin having 3 to 8 carbon atoms is polymerized using a catalyst containing an organoaluminum compound represented by the formula (C) and an organic acid ester compound (C).
A method for polymerizing olefins is provided. In the method of the present invention, a magnesium dialkoxide represented by the general formula Mg(OR ¹ ) ₂ is used. Here, R ¹ represents an alkyl group having 1 to 5 carbon atoms as described above. Specific examples include magnesium dimethoxide, magnesium diethoxide, magnesium dipropoxide, and magnesium dibutoxide. Moreover, although commercially available magnesium dialkoxides can be used, those produced by the reaction of metallic magnesium and alcohol may also be used. The magnesium chloride used in the method of the present invention may be an anhydrous salt, but it is preferable to use an adduct of the alcohol. Such alcohol adducts are represented by the general formula MgCl ₂ ·nR ² OH, where R ² is an alkyl group having 1 to 5 carbon atoms,
n is 0.1 to 10. Specifically, MgCl ₂ .6C ₂ H ₅ OH and the like can be mentioned. When mixing the above-mentioned magnesium dialkoxide and the alcohol adduct of magnesium chloride, preferably the former: the latter = 1 to 4: 4 to 1
(molar ratio) of 100 to 200 under reduced pressure.
Heat to ℃ and process for about 3 to 10 hours. During this heat treatment, a very small amount (above mixture 1) should be added to the system.
You can also add about 1 ml of alcohol per gram. The alcohol added here may be of the same type as the alcohol added during the alcohol treatment to be performed later, or may be of a different type. In the method of the present invention, the above-described mixture of magnesium dialkoxide and magnesium chloride is pulverized, and the resulting pulverized product is subjected to an alcohol treatment by reacting with an alcohol represented by the general formula R ³ OH. Here, R ³ represents an alkyl group or a cycloalkyl group having a straight chain or side chain having 1 to 10 carbon atoms, as described above. Suitable alcohols include primary, secondary or tertiary alcohols having 1 to 10 carbon atoms, more specifically methanol, ethanol, propanol, isopropanol, butanol, isobutanol, amyl alcohol, octanol. etc. can be given. The amount of the alcohol used in the alcohol treatment is not particularly limited and may be selected appropriately depending on various conditions, but it is usually 0.01 to 10 mol, preferably 0.1 to 10 mol, per 1 mol of magnesium in the above-mentioned pulverized material. It should be 5 moles. In addition, the temperature and time of this alcohol treatment may be determined as appropriate, but generally it should be in the range of 0 to 200°C for 5 minutes to 5 hours, preferably 20 to 100°C for 20 minutes to 3 hours. . Furthermore, in the present invention, after performing an alcohol treatment, the obtained product is reacted with an organic acid ester compound, and further a compound of the general formula TiX ¹ ₄ [wherein X ¹ represents a halogen atom] is formed. ] It is necessary to react titanium tetrahalide represented by: Examples of organic acid ester compounds used here include methyl formate, methyl acetate, ethyl acetate, vinyl acetate, propyl acetate, octyl acetate, cyclohexyl acetate, ethyl propionate, methyl butyrate,
Ethyl valerate, methyl chloroacetate, ethyl dichloroacetate, methyl methacrylate, ethyl crotonate, ethyl pivalate, dimethyl maleate, ethyl cyclohexanecarboxylate, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate , octyl benzoate, cyclohexyl benzoate, phenyl benzoate, benzyl benzoate,
Methyl toluate, ethyl toluate, amyl toluate, ethyl ethylbenzoate, methyl anisate, ethyl anisate, ethyl ethoxybenzoate,
Ethyl p-butoxybenzoate, ethyl o-chlorobenzoate, ethyl naphthoate, γ-butyrolactone, δ-valerolactone, coumarin, phthalide,
Examples include esters having 2 to 18 carbon atoms such as ethylene carbonate. Particularly preferred are alkyl esters of aromatic carboxylic acids, such as alkyl esters of aromatic carboxylic acids having 1 to 4 carbon atoms, such as benzoic acid, p-methoxybenzoic acid, p-ethoxybenzoic acid, and toluic acid. In addition, titanium tetrahalide has the general formula
It is represented by TiX ¹ ₄ , where X ¹ represents a halogen atom. Specifically, TiCl ₄ , TiBr ₄ ,
Examples include TiI ₄ . These may be used alone or as a mixture. Among these, it is particularly preferable to use titanium tetrachloride (TiCl ₄ ). The conditions for these reactions are not particularly limited and may be selected appropriately depending on various conditions, etc., but first, an organic acid ester compound is added to the product obtained by alcohol treatment to 1 mole of magnesium in the product. for
About 0.01 to 5 mol, preferably 0.1 to 1 mol, is added, and the reaction is usually carried out at 0 to 200°C for 5 minutes to 5 hours, preferably at 20 to 120°C for 20 minutes to 3 hours. Next, titanium tetrahalide is added to this reaction system in an amount of 0.5 to 100 mol, preferably 1 to 50 mol, per 1 mol of magnesium in the product.
The reaction is carried out at 200°C for 30 minutes to 10 hours, preferably at 50 to 150°C for 1 to 5 hours. In the reactions up to this point, it is also possible to use an inert solvent such as n-heptane, if necessary. After the reaction is completed, the solid product obtained is thoroughly washed with an inert solvent such as n-heptane. After the reaction, it is preferable to remove only the liquid and repeat the above-described addition of titanium tetrahalide and the reaction, since this improves the performance of the solid product as a catalyst. In the present invention, the solid product thus obtained is used as component (A) (solid catalyst component) of an α-olefin polymerization catalyst. According to the present invention, the above solid product is the component (A), and the organoaluminum compound is the component (B),
Furthermore, an organic acid ester compound was used as the (C) component,
α-olefin is polymerized using a catalyst consisting of three components (A), (B), and (C). When polymerizing α-olefin, the reaction system
A dispersion of the solid product as component (A), an organic acid ester compound as component (B), and an organic acid ester compound as component (C) are added, and then α
- Introducing olefin. The polymerization method and conditions are not particularly limited, and any of solution polymerization, suspension polymerization, gas phase polymerization, etc. is possible, and both continuous polymerization and discontinuous polymerization are possible. For example, in the case of solution polymerization or suspension polymerization, the amount of the catalyst component added is 0.001 to 1.0 mmol per titanium atom for component (A), and the amount of component (B) is 0.001 to 1.0 mmol per titanium atom. The amount is 1 to 1000 (molar ratio), preferably 5 to 500 (molar ratio) to titanium atoms. The amount of component (C) added should be 0.01 to 100 (mole ratio), preferably 0.1 to 50 (mole ratio), relative to the titanium atoms in component (A). The α-olefin pressure in the reaction system is preferably normal pressure to 50 kg/cm ² , and the reaction temperature is 30 kg/cm 2 .
~200°C, preferably 50~150°C. Molecular weight adjustment during polymerization can be carried out by known means, such as hydrogen. The reaction time is 10 minutes ~
The time period may be appropriately selected from 10 hours, preferably from 30 minutes to 5 hours. Component (B) of the catalyst used in the method of the present invention is:
As mentioned above, it is an organoaluminum compound represented by the general formula AlR ⁴ _n X ² _3-n . Here, R ⁴ represents an alkyl group having 1 to 5 carbon atoms, m is a real number between 2 and 3, and X ² represents a halogen atom such as chlorine or bromine. Specifically, trimethylaluminum,
Trialkylaluminum compounds such as triethylaluminum, triisopropylaluminium, and triisobutylaluminum, and dialkylaluminum monohalides such as diethylaluminum monochloride, diisopropylaluminum monochloride, and diisobutylaluminum monochloride are preferred, and mixtures thereof are also preferred. It can be given as a thing. Furthermore, the organic acid ester compound which is the component (C) of the catalyst used in the method of the present invention is
The same material as used in the preparation of component (A) can be used. Furthermore, in this case, the organic acid ester compound as component (C) may be exactly the same compound as that used in the preparation of component (A) of the catalyst, or may be a different compound. In the method of the present invention, an α-olefin having 3 to 8 carbon atoms is polymerized using the catalyst described above. Such α-olefin has the general formula R ⁵ —CH=CH ₂ (wherein,
R ⁵ represents an alkyl group having 1 to 6 carbon atoms. ), linear monoolefins such as propylene, butene-1, hexene-1, octene-1, branched monoolefins such as 4-methyl-pentene-1, dienes such as butadiene, and various others. The present invention can be effectively used for homopolymerization of these or copolymerization of various α-olefins. According to the method of the present invention, the activity of the catalyst used is extremely high, and the resulting polymer has great stereoregularity, resulting in extremely high product value. Therefore, since the method of the present invention is a method of highly active polymerization and a polymer with large stereoregularity is obtained, it is possible to simplify or omit the catalyst removal step and the amorphous polymer extraction step. , very efficient polymerization can be carried out. Next, examples of the present invention will be shown. Note that all operations in the following examples were performed under an argon stream. Further, the catalytic activity and isotactic yield (IY) determined in the examples were defined as follows. Catalyst activity: 70℃, 2 hours, propylene partial pressure 7
Weight (Kg) of total polymer produced per 1g of titanium atom during polymerization under conditions of Kg/ ^cm2 . IY = Weight of polymer insoluble in boiling n-heptane/Weight of total polymer produced x 100 (%) Example 1 (1) Production of solid catalyst [Production of catalyst support (ClMgOR)] Average particle diameter of 10μ pulverized with a ball mill of Mg
(OC ₂ H ₅ ) ₂ 10.4 g (91 mmol) and 33.7 g (91 mmol) of MgCl ₂ 6C ₂ H ₅ OH, which was produced by dissolving MgCl ₂ in excess ethanol and distilling off the ethanol.
They were separated and both were mixed. Add a small amount (about 40ml)
Add ethanol, mix, and transfer to a flask.
The mixture was heat-treated at 160° C. for 4 hours under reduced pressure, and the resulting solid was pulverized to form a catalyst carrier. [Production of titanium-supported catalyst] 100 ml of heptane and 2 g of the above-mentioned support (19 mmol as Mg) were added to a 200 ml flask and stirred to suspend. Add 0.18g of ethanol to this suspension.
(3.8 mmol) and reacted at 80°C for 1 hour.
Next, 0.57 g (3.8 mmol) of benzoic acid ethyl ester was added and the reaction was carried out at 80°C for 1 hour, and then 36 g (190 mmol) of titanium tetrachloride was added dropwise at 80°C within 1 hour, and then refluxed for 3 hours. A time reaction was performed. After the reaction was completed, the supernatant liquid was removed by decanting, and 150 ml of heptane was added for washing. This operation was repeated until no chloride ions were detected in the heptane cleaning solution. The supported amount determined by colorimetric method is 20 mg.
-Ti/g- It was a carrier. (2) Polymerization of propylene 400 ml of heptane was added to the dry stainless steel autoclave in step 1. Add to this 2 mmol of triethylaluminum and 0.5 methyl paratoluate.
2 mmol of diethylaluminum chloride and 0.02 mmol of the solid catalyst as Ti were added, and the temperature was raised to 70°C. Add 0.2Kg/ ^cm2 of hydrogen,
By setting the propylene partial pressure to 7Kg/ ^cm2 and continuously introducing propylene, the total pressure is kept constant at 70℃.
Polymerization was carried out for 2 hours. After the polymerization reaction, 70℃
The insoluble polymer was separated by filtration. Furthermore, the filtered polymerization solvent was evaporated to dryness to recover the soluble polymer. The insoluble polymer was treated with boiling n-heptane for 6 hours to extract and separate the atactic polymer. The total polymer yield was 93.0 g and the catalyst activity was 97
Kg/g-Ti, isotactic yield (IY) is
It was 82.1%. Examples 2 to 9 Catalysts were produced in the same manner as in Example 1, except that the carrier produced in the same manner as in Example 1 was used and the type and amount of alcohol were changed in the production of the titanium catalyst. Further, propylene was polymerized using these catalysts under the same conditions as in Example 1. The results are shown in Table 1.

[Table] Example 10 (1) Production of solid catalyst 200 ml of heptane in a 500 ml flask and Example 1
10 g (95 mmol as Mg) of the carrier prepared in the same manner as above was added and stirred to form a suspension. Add 1.8 g (24 mmol) of normal butanol to this suspension.
After the reaction was carried out for 1 hour under reflux, 180 g (950 mmol) of titanium tetrachloride was added dropwise within 1 hour, and the reaction was further carried out for 3 hours under reflux. After the reaction, the supernatant liquid was removed by decanting, and heptane was added.
200ml was added for washing. This operation was repeated until no chlorine ions were detected in the heptane cleaning solution. The supported amount determined by colorimetric method is 34 mg.
It was a Ti/g-carrier. (2) Polymerization of propylene Example 1 according to the method of Example 1 except that the amount of methyl paratoluate was changed to 0.5 mmol.
Polymerization of propylene was carried out under the same conditions as the method described above. The results are shown in Table 2. Examples 11 to 15 (1) Production of solid catalyst Catalysts were produced in the same manner as in Example 10, except that the amount of n-butanol and the amount of ethyl benzoate were changed. (2) Polymerization of propylene The catalyst prepared in (1) above was used, and the rest were as in Example 10.
Polymerization of propylene was carried out under the same conditions. The results are shown in Table 2.

[Table] Example 16 (1) Production of solid catalyst 180 g of titanium tetrachloride was added dropwise to the solid catalyst heptane slurry produced in Example 10 at room temperature, and after raising the temperature, the reaction was carried out under reflux for 3 hours. Thereafter, washing was carried out with heptane in the same manner as in Example 10, and a solid catalyst having a supported amount of 31 mg-Ti/g-carrier was obtained by colorimetric method. (2) Polymerization of propylene Example 1 according to the method of Example 1 except that the amount of methyl paratoluate was changed to 0.7 mmol.
Polymerization of propylene was carried out under the same conditions as the method described above. Catalytic activity is 136Kg/g-Ti, IY is 92.4%,
AD was 0.31. Example 17 (1) Production of solid catalyst 180 g of titanium tetrachloride was added dropwise to the solid catalyst heptane slurry produced in Example 14 at room temperature, and after raising the temperature, the mixture was reacted under reflux for 3 hours. Hereinafter, the same washing as in Example 10 was carried out with heptane, and the amount of support was determined by colorimetric method.
A solid catalyst of 34 mg-Ti/g-support was obtained. (2) Polymerization of propylene Example 1 according to the method of Example 1 except that the amount of methyl paratoluate was changed to 0.7 mmol.
Polymerization of propylene was carried out under the same conditions as the method described above. Catalytic activity is 164Kg/g-Ti, IY is 91.5%,
AD was 0.37.

[Brief explanation of drawings]

FIG. 1 is a drawing showing the steps for preparing a catalyst used in the method of the present invention.

Claims (1)

[Claims] 1 (A) General formula Mg(OR ¹ ) ₂ [wherein R ¹ is a carbon number of 1 to
5 shows the alkyl group. ] A mixture of magnesium dialkoxide and magnesium chloride is added with the general formula R ³ OH [where R ³ is
Indicates an alkyl or cycloalkyl group having ~10 straight or side chains. ] is reacted, and then an organic acid ester compound is reacted, and further the general formula TiX ¹ ₄ [wherein X ¹ represents a halogen atom] is reacted. A solid product obtained by reacting titanium tetrahalide represented by (B) general formula AlR ⁴ _n X ² _3-n [wherein R ⁴ represents an alkyl group having 1 to 5 carbon atoms, m is a real number between 2 and 3,
X ² represents a halogen atom. A method for polymerizing an α-olefin, which comprises polymerizing an α-olefin having 3 to 8 carbon atoms using a catalyst containing an organoaluminum compound represented by the formula (C) and an organic acid ester compound (C). 2 α-olefin having 3 to 8 carbon atoms has the general formula R ⁵
—CH=CH ₂ [In the formula, R ⁵ represents an alkyl group having 1 to 6 carbon atoms. ] The method according to claim 1, wherein the method is represented by: