JPS6351166B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for polymerizing highly stereoregular polyα-olefin using a catalyst comprising a so-called carrier-type titanium component and an organoaluminum compound. In recent years, a method has been developed to increase the activity of the catalyst by supporting the titanium component of the Ziegler-Natsuta catalyst on a carrier, and as a prior art related to this, a combination of a carrier-type titanium component in which a titanium compound is supported on magnesium halide and an organoaluminum compound has been developed. A method of improving the stereoregularity of the resulting polymer by adding an electron-donating compound as a third component has been proposed in JP-A-47-9342. However, when propylene is polymerized with such a conventional two-component system of a carrier-type titanium component and an organoaluminum compound, the polymerization activity is high, but the crystallinity of the resulting polymer is extremely low, and when an electron-donating compound is added to this, the resulting polymer Crystalline polypropylene obtained with titanium trichloride/diethylaluminum monochloride catalyst system, which is currently used industrially, has improved crystallinity, but the activity has been drastically reduced, and the effect of improving crystallinity is not sufficient. It was difficult to obtain products of equivalent quality. The method of JP-A-50-126590 consists of a composition obtained by co-pulverizing magnesium halide and an organic acid ester and reacting it with titanium tetrachloride, an organoaluminum compound, and an organic acid ester. Although catalyst systems have been proposed, the activity and crystallinity of the resulting polymers are also insufficient. The present invention aims to improve the performance of such a supported catalyst. First, after co-pulverizing magnesium halide, organic acid ester, and aliphatic or alicyclic halogenated hydrocarbon compound,
It has been found that the activity of the composition obtained by heat treatment with titanium tetrachloride is greatly improved compared to the composition of JP-A-126590-1983, which is used as the titanium component. However, even if this alone improves activity,
The crystallinity and bulk specific gravity of the produced polymer are low and α-
The performance was not satisfactory as a catalyst for olefin polymerization. Therefore, we investigated the improvement of the crystallinity and bulk specific gravity of the produced polymer with this catalyst system, and found that by coexisting various organic compounds during the co-pulverization described above, the crystallinity and bulk specific gravity of the produced polymer were significantly improved. We have already applied for a patent. We conducted various studies on the above catalysts and found that
There are two drawbacks: solid lumps of the titanium component tend to form during pulverization, and there are many coarse particles in the particle size distribution of the produced polymer, which pose problems when industrially scaled up, and it is necessary to solve these problems. We conducted various studies with the aim of eliminating the above drawbacks, and found that by co-pulverizing magnesium halide with the various compounds mentioned above, we could prevent agglomeration during crushing and improve the roughness of the resulting polymer. The present invention was achieved by discovering that this method is useful for reducing grain size and improving activity. That is, the present invention comprises (A) (a) magnesium halide (b) organic acid ester (c) aliphatic or alicyclic halogenated hydrocarbon compound (d) the following groups (a) to (c) ( At least one selected from a) an aliphatic hydrocarbon compound, an alicyclic hydrocarbon compound, an aromatic hydrocarbon compound, a halogenated aromatic hydrocarbon compound, (b) a liquid propylene oligomer, or (c) an aromatic ether compound. (e) a composition obtained by co-pulverizing five components of aluminum halide and then heat-treating with titanium tetrachloride, (B) an organoaluminum compound, and (C) an organic acid ester or an organic acid ester. A catalyst consisting of a complex with aluminum halide is used for α-olefin polymerization. The manesium halide used as component (A) for preparing component (A) in the method of the present invention is essentially anhydrous magnesium halide, with anhydrous magnesium chloride being particularly preferred. The organic acid ester used as the component (b) has the general formula R ² COOR ¹ (where R ¹ is a C ₁ to _{C 12} aromatic, aliphatic, or alicyclic hydrocarbon residue, and R ² is R ¹ same as or

Aromatic, aliphatic, or alicyclic carboxylic acid esters represented by [formula], such as methyl benzoate, ethyl benzoate, propyl benzoate, phenyl benzoate, ethyl toluate, ethyl anisate, and naphthoate. Examples include ethyl acid, ethyl acetate, butyl acetate, ethyl methacrylate, and ethyl hexahydrobenzoate. As the aliphatic or alicyclic halogenated hydrocarbon compound used as component (iii), saturated or unsaturated halogenated hydrocarbon compounds are used, such as methylene chloride, chloroform, carbon tetrachloride, ethylene dichloride, n- Examples include butyl chloride, propenyl chloride, 1,2-dichloropropane, 1,2-dichloroethylene, hexachloroethane, tetrachloroethylene, tetrabromoethane chlorinated paraffin, and the like. As the component (d), an organic compound selected from the following (a) to (c) is used. (a) Ingredients include n-hexane, n-heptane,
Saturated aliphatic hydrocarbon compounds such as n-octane and iso-octane, pentene-1, hexene-
1. Unsaturated aliphatic hydrocarbon compounds such as octene-1, aromatic hydrocarbon compounds such as benzene, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene, alicyclic carbonization such as cyclohexane and cyclopentane Hydrogen compounds, halogenated aromatic hydrocarbon compounds such as monochlorobenzene, o-dichlorobenzene, m-dichlorobenzene, etc. are used. Component (b) is preferably a slightly viscous liquid propylene oligomer with a molecular weight of about 100 to 1,500, preferably 200 to 1,000. You can use those manufactured by As the component (c), aromatic ether compounds include, for example, methyl phenyl ether, ethyl phenyl ether, allyl phenyl ether, diphenyl ether, and ditolyl ether. As the component (e), substantially anhydrous aluminum halide is used, especially aluminum chloride,
Aluminum bromide is preferred. When describing the method for producing component (A), first of all, (A) ~
(d) Co-pulverizing the components. This pulverization is carried out using a known method commonly used to prepare the titanium component of the Ziegler-Natsuta catalyst.
C. and a pulverization time of 1 to 100 hours under vacuum or an inert gas atmosphere in which moisture, oxygen, etc. are almost completely removed. The composition during pulverization is (a) component 50 to 95 wt%, preferably 55 to 90 wt%, more preferably 60 to 80 wt%,
(b) component 1 to 40 wt%, preferably 2 to 30 wt%, more preferably 3 to 20 wt%, (c) component 1 to 40 wt%,
Preferably 2 to 30 wt%, more preferably 3 to 30 wt%
20wt%, component (d) 1-40wt%, preferably 2-40wt%
30wt%, more preferably 3 to 25wt%, component (e)
It ranges from 0.1 to 10 wt%, preferably from 0.2 to 5 wt%, and more preferably from 0.3 to 3 wt%. The resulting composition is then heat treated with titanium tetrachloride. That is, the above co-pulverized composition is suspended in titanium tetrachloride or its inert solvent solution, and
A method in which free titanium tetrachloride is washed with an inert solvent or dried (if necessary under reduced pressure) after heat treatment in the range of 135°C is preferred. The inert solvent used at this time is aliphatic,
Alicyclic and aromatic hydrocarbons or their halogen derivatives are used, such as hexane, heptane, benzene, toluene, chlorobenzene,
Cyclohexane and the like are preferred. (A) obtained by heat treatment of this titanium tetrachloride
The components are preferably prepared to contain 0.1 to 10 wt% of titanium metal. The organoaluminum compound used in component (B) of the present invention is a trialkylaluminum represented by the general formula AlR ³ ₃ (wherein R ³ represents a C ₁ to _{C 12} alkyl group), such as trimethylaluminum. , triethylaluminum, tri-n-propylaluminum, tri-n-butylaluminum, tri-iso-butylaluminum, tri-n
-Hexylaluminum etc. are used. In the method of the present invention, as component (B), the general formula
AlR ⁴ _o X _3-o (where R ⁴ is a C ₁ to C ₁₂ alkyl group,
is a halogen atom, and n is 1 to 2) It is preferable to add an alkyl aluminum halide, since the activity is improved. Examples of the alkyl aluminum halide include diethylaluminum monochloride, ethylaluminum sesquichloride, ethylaluminum dichloride, diethylaluminium monobromide, diethylaluminum monoiodide, diethylaluminium monofluoride, di-n-propylaluminum monochloride, di-iso- Examples include butylaluminum monochloride and di-n-hexylaluminum monochloride. Although the proportions of component (A) and component (B) used in the method of the present invention can be varied over a wide range, generally 1 to 500 mmol of trialkylaluminium, per 1 mg atom of titanium metal contained in component (A), Preferably 3
~100 mmol, more preferably 5 to 50 mmol, and the alkyl aluminum halide is used per mole of trialkylaluminium.
The amount ranges from 0.05 to 100 mol, preferably from 0.1 to 30 mol, and more preferably from 0.3 to 5 mol. It is preferable to add the trialkylaluminum in small amounts during the polymerization, rather than adding the entire amount at the start of the polymerization, as this provides a better balance between the activity and the crystallinity of the resulting polymer, and there is less change over time in the polymerization rate. Component (C) used in the method of the present invention includes an organic acid ester or a complex of this with aluminum halide. As an organic acid ester
The compound mentioned at the time of component (A) preparation is used, and the organic acid ester and aluminum halide complex is prepared by mixing the above-mentioned organic acid ester and aluminum halide (preferably aluminum chloride or aluminum bromide), or a mixture thereof. It can be prepared by heating. In this case, the molar ratio of organic acid ester and aluminum halide is preferably 1:1. The amount of component (C) used varies depending on the amount of component (B) used, the amount of component (A) used, and polymerization conditions such as Ti content and polymerization temperature, but in general, as component (B) The amount is 5 mol or less, preferably 0.01 to 1.5 mol, more preferably 0.1 to 1 mol, per mol of trialkylaluminum used. The method of the present invention uses the general formula R-CH=CH ₂ (where R
represents an alkyl group having 1 to 10 carbon atoms), and the above α-olefins are used for block or random copolymerization with ethylene. Examples of the α-olefin include propylene, buty-1, hexene-1, and 4-methyl-
Examples include Penten-1. For the polymerization reaction according to the method of the present invention, conventional methods and conditions commonly used in the art can be employed. The polymerization temperature at that time is 20 to 100℃, preferably 40 to 90℃, and the polymerization pressure is usually 1 to 60℃.
Kg/cm ² abs, preferably in the range of 1 to 50 kg/cm ² abs. Polymerization reactions can generally use aliphatic, alicyclic, aromatic hydrocarbons, or mixtures thereof, as solvents, such as propane, butane, pentane, hexane, heptane, cyclohexane, benzene, etc., and mixtures thereof. is used. In addition, a bulk polymerization method using the liquid monomer itself as a solvent, and conditions where the solvent is substantially absent,
That is, it can be carried out by a so-called gas phase polymerization method in which a gaseous monomer and a catalyst are brought into contact. The molecular weight of the polymer produced in the method of the present invention varies depending on the reaction mode, catalyst system, and polymerization conditions, but can be controlled by adding hydrogen, alkyl halides, zinc sialkyl, etc., as necessary. be able to. In the present invention, the activity of the catalyst is high, and the ratio of the n-heptane extraction residue polymer in the produced polymer is 95%.
Since it reaches ~97%, a polymer with sufficient physical properties can be obtained even if extraction or removal of the amorphous polymer is omitted, making it possible to simplify the process. Furthermore, in the present invention, since lumps are less likely to form during the grinding in the process of preparing component (A), it is possible to increase the amount of raw material charged to the grinder, and since there are fewer coarse particles of the produced polymer, there are no problems with handling the slurry. It is of great practical value industrially. Examples of the present invention will be shown below. Example 1 (1) Preparation of catalyst (A) component A vibratory mill equipped with a grinding pot having an internal volume of 600 ml and containing 80 steel balls with a diameter of 12 mm is prepared. In this pot, in a nitrogen atmosphere, add 30 g of anhydrous magnesium chloride, 3.15 g of ethyl benzoate, and chloroform.
3.45 g, diphenyl ether 5.1 g, and aluminum chloride 0.38 g were charged, and pulverization was carried out for 20 hours. When the pulverizing pot was opened, there were no lumps, and no pulverized material was observed adhering to the pot wall or steel balls. In a 300 ml round bottom flask under nitrogen atmosphere, add 10 g of the above pulverized composition, 100 ml of n-heptane, and titanium tetrachloride.
1.5 ml was taken, stirred at 80°C for 2 hours, and the supernatant liquid was removed by decantation. Next, 200 ml of n-heptane was added, the mixture was stirred at room temperature for 30 minutes, and the supernatant liquid was removed by decantation, which was repeated 5 times. Furthermore, 200 ml of n-heptane was added to obtain a slurry of a composition (component (A) of the present invention) in which a titanated compound was supported. Sample this part and n
- When heptane was evaporated and analyzed, the composition was found to be
It contained 1.12wt% Ti. (2) Polymerization n-heptane in a 2L autoclave made of SUS-32
1l, 0.15g of component (A) prepared in (1) (as titanium atoms)
0.035mgatom), tri-iso-butyl aluminum
0.4ml (1.59mM), ethyl benzoate 0.10ml
(0.7mM) in a nitrogen atmosphere to prepare the catalyst of the present invention. After evacuating the nitrogen in the autoclave with a vacuum pump, hydrogen was added at a gas phase partial pressure of 0.3 kg/
cm ² was charged, and then propylene was charged to adjust the pressure in the gas phase to 2 Kg/cm ² gauge. The contents of the autoclave were heated, and after 5 minutes, the internal temperature was raised to 70°C, and the polymerization was continued for 2 hours while charging propylene to maintain the polymerization pressure at 5 kg/cm ² gauge at 70°C. After the autoclave was cooled, unreacted propylene was purged and the contents were taken out and filtered to obtain 238 g of white powdery polypropylene. The proportion of the boiling n-heptane extraction residual polymer (crystalline polypropylene) in this powdered polypropylene (hereinafter abbreviated as Powder II) is 96.4wt%.
Bulk specific gravity is 0.48g/ml, intrinsic viscosity 1.64dl/g
(Measured in a tetralin solution at 135°C, the same applies hereinafter). On the other hand, 3 g of n-heptane soluble polymer (amorphous polypropylene) was obtained by concentrating the liquid. The ratio of the boiling n-heptane extraction residual polymer to the total polymer produced, ie, the total II, was 95.2 wt%. The polymerization activity of the catalyst in this polymerization was 803g/g-(A).
hr, 72Kg/g-Ti.hr The amount of polypropylene obtained is
They were 1606g/g-(A) and 143Kg/g-Ti. The obtained polypropylene powder was sieved and the particle size distribution was measured, and the coarse particles (hereinafter simply referred to as coarse particles) on the 10 mesh sieve were 1.0 wt%.
The fine particles under the 200 mesh sieve (hereinafter simply referred to as fine particles) were 8.3 wt%. Comparative Example 1 (1) Preparation of catalyst (A) component Grinding was carried out in the same manner as in Example 1 except that the addition of aluminum chloride was omitted. When the crushing pot was opened, approximately 5 g of crushed material was found adhering to the pot wall and sphere. The obtained pulverized product was heat treated with titanium tetrachloride and washed with n-heptane in the same manner as in Example 1, to obtain a slurry of a composition supporting a titanium compound with a titanium content of 1.32 wt%. (2) Polymerization 0.20g of the composition prepared in (1) (as titanium atoms)
Polymerization was carried out in exactly the same manner and under the same conditions as in Example 1, except that 0.055 mg/atom) was used as component (A), and 232 g of powdered polypropylene was obtained. This powdered polypropylene powder II is
96.1wt%, bulk specific gravity 0.48g/ml, limiting viscosity number 1.63
It was dl/g. On the other hand, by concentrating the liquid, amorphous polypropylene is produced.
3g was obtained. The total II of the obtained polymer is
It was 94.9wt%. The polymerization activity of the catalyst in this polymerization was 588g/g-
(A)・hr, 45Kg/g-Ti・hr, and the amount of polypropylene obtained was 1175g/g-(A), 89Kg/g-Ti. The obtained polypropylene powder was sieved and the particle size distribution was measured, and the coarse particles were 7.0wt%.
The fine particles were 10.8wt%. Comparing these results with Example 1 of the present invention, it can be seen that the activity in Example is about 40% greater, the number of coarse particles and fine particles is small, and the particle size distribution is narrow and uniform. Example 2 0.15 g of component (A) prepared in Example 1 (1) (0.035 mgatom in terms of titanium metal atoms), 0.12 ml (0.97 mM) of diethylaluminum monochloride, 0.10 ml (0.07 mM) of ethyl benzoate, triiso -Butylaluminum 0.4ml (1.59mM) was used as a catalyst component, of which tri-iso-butylaluminum was injected into the autoclave in 6 parts at 20 minute intervals, and the polymerization time was controlled.
Table 1 shows the results of polymerization carried out in the same manner as in Example 1 except that the time was changed to 2.5 hours. Examples 3 to 4 Polymerization was carried out under exactly the same conditions as in Example 2, except that equimolar amounts of ethylaluminum sesquichloride or ethylaluminum dichloride were used in place of diethylaluminum monochloride in the method of Example 2. The results are shown in Table 1.

【table】

[Table] Examples 5 to 12 In the production of component (A) in Example 1 (1), component (A) was produced using various halogenated hydrocarbon compounds in place of chloroform used as component (c). Manufactured. Table 2 shows the results of polymerization carried out under the same conditions as in Example 2 except that this was used as component (A). Examples 13-23 In the production of component (A) in Example 1 (1), component (A) was produced by using various component (2) instead of diphenyl ether used as component (2). did. Table 3 shows the results of polymerization conducted under the same conditions as in Example 2 except that this was used as component (A).

【table】

[Table] Examples 24 to 31 Among the methods for preparing component (A) in Example 1 (1), the compositions of magnesium chloride, ethyl benzoate, chloroform, and diphenyl ether aluminum chloride during grinding were as shown in Table 4. Component (A) was prepared in the same manner as in Example 1 (1) except for the following changes. This was used as component (A) and polymerization was carried out under the same conditions as in Example 1, and the results are shown in Table 4.

【table】

[Table] Example 32 The same procedure as in Example 2 except that 0.198 g of a 1:1 complex of ethyl benzoate and aluminum chloride was used instead of ethyl benzoate used during polymerization, and the polymerization time was changed to 2 hours. Table 5 shows the results of polymerization under these conditions.

【table】

[Table] Example 33 Polymerization was carried out under exactly the same conditions as in Example 2 except that a mixed gas of propylene and ethylene containing 1.0 wt% ethylene was used instead of propylene as the monomer. Polypropylene powder with polymerization time of 2.15 hours
503 g and 7 g of amorphous polypropylene were obtained.
Powder II of the obtained polypropylene powder
is 96.0wt%, intrinsic viscosity 1.70dl/g, bulk specific gravity
The ethylene content was 0.47 g/ml and 0.6 wt%. The total II in this polymerization reaction was 94.7%, and the polymerization activity was
1581g/g-(A). hr, 41Kg/g-Ti.hr, the amount obtained was 3400g/g-(A), 304Kg/g-Ti. Example 34 Polymerization was continued for 1.7 hours according to the method of Example 2.
After polymerizing 400g of propylene, it is cooled and the inside of the autoclave is replaced with ethylene.
Add 0.1ml of butyl aluminum and hydrogen partial pressure 1.5
Kg/cm ² abs, polymerization pressure 5Kg/cm ² G, polymerization temperature 70℃
Polymerization was continued for 0.6 hours to obtain 518 g of powder and 7 g of amorphous polymer. The obtained powder, Powder II, had an intrinsic viscosity of 97.0 wt%, an intrinsic viscosity of 1.83 dl/g, a bulk specific gravity of 0.48 g/ml, and an ethylene content of 1.83 wt%. The total I.I in this polymerization reaction was 95.7wt%, and the polymerization activity was
1527g/g-(A). hr, 136Kg/g-Ti・hr, and the amount obtained was 3500g/g-(A), 312Kg/g-Ti.

[Brief explanation of the drawing]

FIG. 1 is a flowchart of the Ziegler catalyst according to the present invention.

Claims (1)

[Claims] 1 (A) (a) Magnesium chloride (b) Organic acid ester (c) Aliphatic or alicyclic halogenated hydrocarbon compound, (d) The following groups (a) to (c) , that is, selected from (a) an aliphatic hydrocarbon compound, an alicyclic hydrocarbon compound, an aromatic hydrocarbon compound, a halogenated aromatic hydrocarbon compound, (b) a liquid propylene oligomer, or (c) an aromatic ether compound. (e) a composition obtained by co-pulverizing aluminum trihalide and then heat-treating it with titanium tetrachloride; (B) an organoaluminum compound; and (C) an organic acid ester or an organic acid. A method for polymerizing α-olefin, which comprises polymerizing α-olefin using a catalyst consisting of a complex of an ester and an aluminum halide.