JPS642125B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing polyolefins, and more specifically, the present invention relates to a method for producing polyolefins having 2 to 8 carbon atoms, using a solid component obtained by reacting a specific compound, a catalyst consisting of an organometallic compound, and an organic acid ester compound. This invention relates to a method for polymerizing α-olefin to produce highly stereoregular polyolefin with high activity. Conventionally, methods for stereoregularly polymerizing olefins using a catalyst consisting of a solid catalyst component containing magnesium, halogen, and titanium and an organometallic compound have been known, for example, as described in Japanese Patent Publication No. 46-34098,
There are methods disclosed in JP-A-52-98076 and JP-A-53-2580. However, all of the above conventional methods have advantages and disadvantages, and each has drawbacks such as a low bulk density of the resulting polymer, poor particle size distribution, low stereoregularity, or insufficient polymerization activity. In particular, there is an inverse correlation between the polymerization activity of the catalyst and the stereoregularity of the produced polymer, and it has so far been extremely difficult to simultaneously maintain both of them. The present inventors have conducted extensive research in order to overcome the drawbacks of the above-mentioned conventional techniques and to develop a method for producing polyolefins with high bulk density while maintaining a high degree of both polymerization activity and stereoregularity of the resulting polymer. .
As a result, they discovered that the object could be achieved by using a reaction mixture of magnesium dialkoxide, a halogen-containing alkoxytitanium compound, an organic acid ester compound, and a halogenating agent as a component of the catalyst, and completed the present invention. I came to the conclusion. That is, the present invention provides (A) a magnesium dialkoxide represented by the general formula Mg(OR ¹ ) ₂ [wherein R ₁ is an alkyl group having 1 to 5 carbon atoms], a magnesium dialkoxide represented by the general formula Ti
(OR ² ) _o X ¹ _4-o [In the formula, R ² represents an alkyl group having 1 to 5 carbon atoms, X ¹ represents a halogen atom, and n is 0
It is a real number in the range <n<4. ] Halogen-containing alkoxy titanium compounds, organic acid ester compounds and SiCl ₄ , SnCl ₄ , ZrCl ₄ and the general formula AlR ³ X ² ₂ [wherein R ³ represents an alkyl group having 1 to 5 carbon atoms, ² represents a halogen atom. A solid component obtained by reacting a halogenating agent selected from alkylaluminum halides represented by (B) general formula AlR ⁴ ₃ [wherein R ⁴ represents an alkyl group having 1 to 5 carbon atoms]. The present invention provides a method for producing a polyolefin, which comprises polymerizing an α-olefin having 2 to 8 carbon atoms using a catalyst consisting of an organometallic compound represented by the following formula and an organic acid ester compound (C). As mentioned above, in the method of the present invention, the catalyst
As component (A), a solid component produced by reacting four types of compounds: a magnesium dialkoxide, a halogen-containing alkoxytitanium compound, an organic acid ester, and a halogenating agent is used. Among the above compounds, magnesium dialkoxide is represented by the general formula Mg(OR ¹ ) ₂ as described above, where R ¹ represents an alkyl group having 1 to 5 carbon atoms. Preferred examples of magnesium dialkoxides 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. Next, the halogen-containing alkoxytitanium compound is
It is represented by the general formula Ti(OR ² ) _o X ¹ _4-o ,
Here, R ² , X ¹ , and n are as described above. That is,
R ² represents an alkyl group having 1 to 5 carbon atoms, and X ¹ represents a halogen atom such as chlorine or bromine. Further, n is usually 1, 2 or 3, but may be a real number in the range of 0<n<4 as the average value of the mixture. Specifically, these halogen-containing alkoxytitanium compounds include Ti(OCH ₃ )Cl ₃ , Ti(OC ₂ H ₅ )Cl ₃ , Ti
Trihalogenated alkoxy titanium such as (O・n-C ₄ H ₉ ) Cl ₃ , Ti (OC ₂ H ₅ ) Br ₃ , Ti
(OCH ₃ ) ₂ Cl ₂ , Ti (OC ₂ H ₅ ) Cl ₂ , Ti (O・n-
Dihalogenated alkoxytitanium such as C ₄ H ₉ ) ₂ Cl ₂ , Ti(OC ₂ H ₅ ) ₂ Br ₂ , Ti(OCH ₃ ) ₃ Cl, Ti
(OC ₂ H ₅ ) ₃ Cl, Ti (O・n-C ₄ H ₉ ) ₃ Cl, Ti
Examples include monohalogenated trialkoxytitanium such as (OC ₂ H ₅ ) ₃ Br. Furthermore, specific examples of organic acid ester compounds include methyl formate, methyl acetate, ethyl acetate, vinyl acetate, propyl acetate, octyl acetate, cyclohexyl acetate, ethyl propionate, methyl butyrate, ethyl valerate, methyl chloroacetate, and 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, toluyl ethyl acid, amyl toluate, ethyl ethylbenzoate, methyl anisate,
Ethyl anisate, ethyl ethoxybenzoate, p-
Ethyl butoxybenzoate, ethyl o-chlorobenzoate, ethyl naphthoate, γ-butyrolactone,
Examples include esters having 2 to 18 carbon atoms such as δ-valerolactone, coumarin, phthalide, and ethylene carbonate, but especially alkyl esters of aromatic carboxylic acids such as benzoic acid, p-methoxybenzoic acid, and p-ethoxybenzoic acid. C1-4 alkyl esters of aromatic carboxylic acids such as benzoic acid and toluic acid are preferred. In addition, as ^a halogenating agent, SiCl ₄ (silicon tetrachloride ⁾ , SnCl ₄ (tin tetrachloride), ZrCl ₄ (zirconium tetrachloride) and _the general formula AlR ³ It represents an alkyl group, and X ² represents a halogen atom. ] An alkyl aluminum halide represented by the following formula is used. Specific examples of the alkyl aluminum halide represented by the above general formula include ethyl aluminum dichloride, isopropylaluminum dichloride,
Examples include isobutylaluminum dichloride. In the present invention, the above-mentioned four types of compounds, that is, magnesium dialkoxide, halogen-containing alkoxytitanium compound, organic acid ester compound, and halogenating agent, are mixed and reacted, but the order of mixing is not particularly limited, and the above-mentioned four types of compounds are mixed and reacted. The compounds may be mixed simultaneously. Alternatively, after mixing magnesium dialkoxide and a halogen-containing alkoxy titanium compound, adding an organic acid ester compound and then adding a halogenating agent, or after mixing magnesium dialkoxide and an organic acid ester compound, adding a halogen-containing alkoxy titanium compound. In addition, the halogenating agent may be further added, or the halogenating agent may be added after mixing three types of compounds excluding the halogenating agent. When reacting the above-mentioned four types of compounds, there is no particular restriction on their blending ratio, but 0.01 to 100 mol, preferably 1 to 20 mol, of the halogen-containing alkoxytitanium compound is added to 1 mol of magnesium dialkoxide. , organic acid ester compound
The amount of the halogenating agent is 0.001 to 10 mol, preferably 0.05 to 5 mol, and the halogenating agent is 0.1 to 10 mol, preferably 0.5 to 5 mol. Although these reactions can be carried out without a solvent, they are usually carried out in a solvent such as an aliphatic hydrocarbon such as pentane, hexane, heptane, or octane, or an aromatic hydrocarbon such as benzene, toluene, or xylene. . Furthermore, the reaction conditions are as follows:
Although it may be selected as appropriate, the reaction temperature is usually 0 to 200°C, preferably 30 to 150°C for 5 minutes to 10 hours.
Preferably, the reaction may be carried out for 30 minutes to 5 hours. In the method of the present invention, the solid component obtained by the above-mentioned reaction is separated from the reaction solution, thoroughly washed, and then used as the component (A) of the catalyst. According to the present invention, the above solid component is the component (A), the organometallic compound is the component (B), and the organic acid ester compound is the component (C). A polyolefin is produced by polymerizing an α-olefin having 2 to 8 carbon atoms using a catalyst comprising component (2). When polymerizing α-olefins having 2 to 8 carbon atoms, a dispersion of a solid component as the (A) component of the catalyst, an organometallic compound as the (B) component, and (C) are added to the reaction system.
An organic acid ester compound as a component is added, and then an α-olefin as a raw material is introduced into the system. 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. Taking the case of solution polymerization or suspension polymerization as an example, the amount of the catalyst component added is 0.001 to 1.0 mmol/, preferably 0.005 to 0.5 mmol/in terms of titanium atoms of component (A), and (C) The amount of the component is 1 to 1000 (molar ratio), preferably 5 to 500 (molar ratio) to the titanium atoms in component (A). In addition, the amount of component (B) added is 1 to 1000 per titanium atom in component (A).
(molar ratio), preferably 5 to 500 (molar ratio). In addition, the olefin pressure in the reaction system is from normal pressure to 50
Kg/cm ² is preferred and the reaction temperature is 20-200°C, preferably 40-150°C. Molecular weight adjustment during polymerization can be carried out by known means, such as hydrogen. The reaction time may be appropriately selected from 5 minutes to 10 hours, preferably from 30 minutes to 5 hours. The organometallic compound which is component (B) of the catalyst used in the method of the present invention has the general formula AlR ⁴ ₃ [wherein R ⁴ represents an alkyl group having 1 to 5 carbon atoms]. ], examples of which include trimethylaluminum, triethylaluminum, triisopropylaluminium, triisobutylaluminum, etc., and mixtures thereof can also be suitably used. On the other hand, the organic acid ester compound which is the component (C) of the catalyst used in the present invention may be the same as that used in obtaining the component (A) described above, but a different one may be used. α- having 2 to 8 carbon atoms that can be polymerized by the method of the present invention
There are various types of olefins, such as ethylene, propylene, butene-1, hexene-
Examples include linear monoolefins such as 1, octene-1, and branched monoolefins such as 4-methyl-pentene-1. α of
- Can be effectively used for copolymerization of 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 gas flow. Moreover, the stereoregularity coefficient (II) determined in the examples was defined as follows. II = Boiling of polymer insoluble in solvent during polymerization Weight of n-heptane insoluble polymer / Weight of polymer insoluble in solvent during polymerization x 100 (%) Example 1 (1) Production of solid catalyst component In a 500 ml glass flask, -Pour 150ml of heptane and add 10.0g of magnesium diethoxide.
(88 mmol) and added 2.64 g of it at room temperature.
(17.6 mmol) of ethyl benzoate was added. In addition, n-butoxytitanium trichloride (Ti
(n-C ₄ H ₉ O) Cl ₃ ) 200 g (880 mmol) was added and reacted at 100° C. for 3 hours. Then increase the temperature to 80
The temperature was lowered to 0.degree. C. and allowed to stand, the supernatant liquid was removed, and the mixture was thoroughly washed with n-heptane. The obtained solid component (hereinafter,
It is called _P1 . ) was added with 150 ml of n-heptane to suspend the solid. Next, silicon tetrachloride (SiCl ₄ ) was added in an amount of 1 times the mole of Ti in P ₁ at room temperature.
The reaction was carried out at ℃ for 1 hour. After the reaction was completed, it was thoroughly washed with n-heptane to obtain a catalyst slurry. The amount of Ti supported on the obtained catalyst slurry was determined by a colorimetric method, and it was found to be 31 mg-Ti/g-support. (2) Polymerization of propylene Purified n-heptane 400ml in autoclave 1
ml, triethylaluminum 2.0 mmol, p-
0.6 mmol of methyl toluate and 0.02 mmol of the above solid catalyst component as Ti were added, and the temperature was raised to 70°C. Next, 0.2 Kg/cm ² of hydrogen was added, and polymerization was carried out for 2 hours while maintaining the total pressure at 7.5 Kg/cm ² with propylene.
As a result, 92 g of solid polypropylene was obtained.
The catalytic activity was 96 kg/hour for 1 g of Ti. The II of this polymer is 86.3% and the bulk density is 0.34
g/ml. Additionally, 10.3g of soluble polymer was recovered from the polymerization solvent. (3) Polymerization of ethylene Purified n-hexane 400ml in autoclave 1
ml, add 2.0 mmol of triethylaluminum and 0.01 mmol of the above solid catalyst component as Ti 80
The temperature was raised to ℃. Next, 3 kg/cm ² of hydrogen and 5 kg/cm ² of ethylene were added. Furthermore, polymerization was carried out for 1 hour while continuously supplying ethylene so as to maintain the total pressure at 9.3 Kg/cm ² . As a result, 86.4 g of polyethylene was obtained. Catalytic activity is Ti1g, 180Kg per hour
It was hot. The bulk density of the polymer was 0.29 g/ml and the melt index (MI) was 2.8 g/10 min. Comparative Example 1 In Example 1 (2), P ₁ was used as the solid catalyst component.
Polymerization of propylene was carried out under the same conditions as in Example 1(2) except that 0.02 mmol of Ti was used.
As a result, 38.4 g of polypropylene was obtained. The catalytic activity was 40 kg per hour for 1 g of Ti. The II of this polymer is 80.5% and the bulk density is 0.30g/
It was hot in ml. Also, the soluble polymer is more soluble than the polymerization solvent.
18.3g was recovered. Example 2 (1) Production of solid catalyst component 150 ml of n-heptane was placed in a 500 ml glass flask, and 10.0 g of magnesium diethoxide was added thereto.
(88 mmol) and added 2.64 g of it at room temperature.
(17.6 mmol) of ethyl benzoate was added. In addition, n-butoxytitanium trichloride (Ti
(n-C ₄ H ₉ O) Cl ₃ ) 200 g (880 mmol) was added and reacted at 80° C. for 3 hours. After the reaction was completed, the solid component was thoroughly washed with n-heptane. Next, ethylaluminum dichloride was added at room temperature in an amount equivalent to 5 times the mole of Ti in the solid component, and then the temperature was raised and the mixture was reacted at 60°C for 15 minutes. After the reaction is complete, n-
The catalyst slurry was obtained by thorough washing with heptane. The amount of Ti supported on the obtained catalyst slurry was determined by a colorimetric method, and it was found to be 20 mg-Ti/g-support. (2) Polymerization of propylene Example 1(2) except that the solid catalyst component in Example 2(1) was used as the solid catalyst component in Example 1(2).
Polymerization of propylene was carried out under the same conditions. As a result, 142.0 g of polypropylene was obtained. The catalytic activity was 148 kg/hour for 1 g of Ti. The II of this polymer is 82.5% and the bulk density is 0.31
g/ml. Additionally, 21.0 g of soluble polymer was recovered from the polymerization solvent. Example 3 (1) Production of solid catalyst component In Example 1 (1), silicon tetrachloride (SiCl ₄ )
A solid catalyst component was produced under the same conditions as in Example 1 (1) except that SnCl ₄ was used in place of 5 times the mole of Ti in P ₁ . When the amount of Ti supported on the obtained solid catalyst component was determined by colorimetric method, it was found to be 32mg-Ti/
g-carrier. (2) Polymerization of propylene Propylene was polymerized under the same conditions as in Example 1 (2) except that the solid catalyst component in Example 3 (1) was used. As a result, 50.3 g of polypropylene was obtained. II of this polymer is 80.9%
The bulk density was 0.28 g/ml. Also,
13.7g of soluble polymer was recovered from the polymerization solvent. Example 4 (1) Production of solid catalyst component In Example 1 (1), 200 g of n-butoxytitanium trichloride (Ti(n-C ₄ H ₉ O) Cl ₃ )
(880 mmol) of zirconium tetrachloride without washing with n-heptane.
A solid catalyst component was produced under the same conditions as in Example 1(1), except that 1 mmol) was added and the reaction was carried out at 100° C. for 3 hours. The obtained solid catalyst component was measured by colorimetric method.
The amount of Ti supported was determined to be 34 mg-Ti/g-support. (2) Polymerization of propylene Propylene was polymerized under the same conditions as in Example 1 (2) except that the solid catalyst component in Example 4 (1) was used. As a result, 183 g of polypropylene was obtained. The catalytic activity was 191 kg/hour for 1 g of Ti. II of this polymer is 85.2%
The bulk density was 0.30 g/ml. Also,
18.3 g of soluble polymer was recovered from the polymerization solvent. Example 5 (1) Production of solid catalyst component 150 ml of n-heptane was placed in a 500 ml glass flask, and 10.0 g of magnesium diethoxide was added thereto.
(88 mmol) was suspended, and 10.3 g (44 mmol) of zirconium tetrachloride and 2.64 g (17.6 mmol) of ethyl benzoate were added thereto and reacted at 98°C for 1.5 hours. The temperature was then lowered to 80°C and n-butoxytitanium trichloride (Ti(n-C ₄ H ₉ O)
After 200 g (880 mmol) of Cl ₃ ) was added dropwise, the temperature was raised and the reaction was carried out at 100° C. for 3 hours. After the reaction is complete, n-
A solid catalyst component was obtained by thorough washing with heptane. When the amount of Ti supported on the obtained solid catalyst component was determined by a colorimetric method, it was found to be 21 mg-Ti/g-support. (2) Polymerization of propylene Propylene was polymerized under the same conditions as in Example 1 (2) except that the solid catalyst component in Example 5 (1) was used. As a result, 130.0 g of polypropylene was obtained. The catalytic activity was 135 kg per hour for 1 g of Ti. II of this polymer is 83.8%
The bulk density was 0.30 g/ml. Also,
11.2g of soluble polymer was recovered from the polymerization solvent. Examples 6 to 8 In Example 1, solid catalyst components were produced under various conditions and propylene was polymerized. The results are shown in Table-1. 【table】

[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 [In the formula, R ¹ is a carbon number of 1 to
Magnesium dialkoxide represented by the general formula Ti(OR ² ) _o X ¹ _4-o [in the formula, R ² represents an alkyl group having 1 to ⁵ carbon atoms, and , n are real numbers in the range 0<n<4. ] Halogen-containing alkoxytitanium compounds, organic acid ester compounds, and SiCl ₄ ,
SnCl ₄ , ZrCl ₄ and the general formula AlR ³ X ² ₂ [wherein R ³ represents an alkyl group having 1 to 5 carbon atoms, and X ² represents a halogen atom]. ] A solid component obtained by reacting a halogenating agent selected from alkyl aluminum halides represented by (B) general formula AlR ⁴ ₃ [wherein,
R ⁴ represents an alkyl group having 1 to 5 carbon atoms. A method for producing a polyolefin, which comprises polymerizing an α-olefin having 2 to 8 carbon atoms using a catalyst consisting of an organometallic compound represented by the following formula and (C) an organic acid ester compound.