JPH06287217A - Solid catalyst component for polymerizing olefin and its polymerization - Google Patents

Abstract

PURPOSE:To obtain a solid catalyst component for polymerizing olefins in high yield, capable of obtaining polyolefins containing almost no fine polymers of <=200mum size, having a narrow size distribution and almost a spherical particle shape and excellent in stereospecificity and flow properties, and to polymerize olefins by using a polymerization catalyst containing the same catalyst component. CONSTITUTION:The subject solid catalyst component for polymerizing olefins is obtained through the first catalytic reaction process where a suspension consisting of spherical dialkoxy magnesium (a), a liquid aromatic hydrocarbon at normal temperature (b) and phthalic acid diester (c) is added and reacted with a mixed solution of (b) material and titanium tetrachloride (d), the second catalytic reaction process where the reaction product is washed with an aromatic hydrocarbon and then reacted with titanium tetrachloride (d) and the treating process where the produced solid component is dried, subjected to removal of fine powders and incorporated with a powdery nonionic surfactant (e). The subject polymerization method comprises polymerizing olefins in the presence of a catalyst formed with the solid catalyst component, an organoaluminum compound and an organosilicon compound.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a solid catalyst component for olefin polymerization and a solid catalyst component for producing a polyolefin having a very small amount of a finely divided polymer having a particle size of 200 μm or less and having excellent stereoregularity in a high yield. The present invention relates to a method for polymerizing olefins using a catalyst containing

[0002]

2. Description of the Related Art Conventionally, a solid catalyst component for polymerization of olefins containing titanium halides, magnesium compounds and electron-donating compounds as essential components, and olefin polymerization comprising the solid catalyst components and organoaluminum compounds, silicon compounds, etc. Many proposals have been made for a method of polymerizing or copolymerizing an olefin in the presence of a catalyst for use.

For example, Japanese Patent Application Laid-Open No. 63-
No. 3010, a solid catalyst component prepared by heating a product obtained by contacting dialkoxy magnesium, a diester of an aromatic dicarboxylic acid, an aromatic hydrocarbon and a titanium halide in a powder state, A catalyst for olefin polymerization comprising an organoaluminum compound and an organosilicon compound has been proposed, and an olefin polymerization method in the presence of the catalyst is exemplified.

Similarly, a magnesium compound obtained by reacting a metal magnesium powder with an alkyl monohalide in the presence of iodine and a tetraalkoxytitanium, an aliphatic hydrocarbon and an aliphatic alcohol are mixed in a mixed solution, and A solid catalyst component prepared by contacting titanium tetrachloride in the presence of an aromatic hydrocarbon with a solid product obtained by adding titanium chloride to precipitate a solid substance and adding a diester of phthalic acid, and an organoaluminum A catalyst composed of a compound and a silicon compound (JP-A-63-154705) or a suspension formed of diethoxymagnesium and an alkylbenzene is contacted with titanium tetrachloride, and then the silicon compound and phthalic acid dichloride are added. The solid product obtained by the reaction is washed with alkylbenzene, A catalyst composed of a solid catalyst component prepared by catalytic reaction with titanium tetrachloride in the presence of killbenzene and an organoaluminum compound and an organosilicon compound (JP-A-1-221405) has been proposed. A method of polymerizing olefins is disclosed.

These prior arts are so-called for removing catalyst residues such as chlorine and titanium remaining in the produced polymer.
It started with the development of a catalyst component with high activity that could eliminate the deashing step, and at the same time focused on improving the yield of stereoregular polymer and enhancing the sustainability of catalyst activity during polymerization. There are excellent effects for this purpose.

However, when olefins are polymerized using a polymerization catalyst having a composition of this type of highly active catalyst component and an electron donating compound represented by an organoaluminum compound and a silicon compound, a polymer produced is obtained. It contained a large amount of fine powder and tended to have a broad particle size distribution. When the production amount of this fine powder polymer is increased, it hinders the continuation of a uniform reaction and causes a process obstacle such as clogging of the pipe during the transfer of the polymer, and when the particle size distribution is wide, the molding process of the polymer is eventually performed. It also has an unfavorable effect. For this reason, in the art, fine powder having a particle size of 200 μm or less, which has a particularly large influence, is as small as possible, and it has been a factor for seeking a polymer having a uniform particle size and a narrow particle size distribution.

As a means for solving this problem, an attempt has been proposed to obtain an olefin polymer having a small amount of finely divided polymer and excellent particle size characteristics by improving the composition and preparation method of the solid catalyst component used for olefin polymerization. There is. For example, in JP-A-58-83006, magnesium chloride is dissolved in 2-ethylhexyl alcohol, and then a solid catalyst component is precipitated with titanium tetrachloride. In the presence of this catalyst component, organoaluminum and an electron donor. It is disclosed that when olefin polymerization is carried out, a polymer having almost no fine powder and a narrow particle size distribution can be obtained. Further, in JP-A-3-72503, dialkoxymagnesium, tetraalkoxytitanate and an organic silicon compound are heated and reacted as starting materials, and the obtained reaction product is treated with a titanium halide or a carboxylic acid such as a metal salt of orthophthalic acid. A method for olefin polymerization in the presence of a catalyst composed of a solid catalyst component obtained by treatment with an acid derivative and an electron-donating compound such as an organometallic compound and a piperidine derivative is disclosed, and its examples show particle characteristics. It has been shown that a highly stereoregular polymer excellent in yield was obtained in high yield.

[0008]

However, in the method disclosed in Japanese Patent Laid-Open No. 58-83006 described above, since a large amount of the solubilizer and the precipitant are used in the catalyst component preparation step, the post-process of the waste liquid treatment and a corresponding apparatus are used. Therefore, there is a problem that not only the process becomes complicated, but also the effect of controlling the particle size distribution, in particular, the problem of reduction of the finely divided polymer is not achieved. On the other hand, in the method disclosed in JP-A-3-72503, as is clear from the description of the examples, two kinds of titanium compounds as active ingredients and substantially three kinds of electron donors are used in preparation of the catalyst component, The preparation means is complicated, such as the use of components that require extremely close processing operations for stable synthesis such as carboxylic acid derivatives such as metal salts of orthophthalic acid, and the process is costly and costly for industrial scale production. There are still many issues to be improved.

In addition to the above, there is a method of performing a sizing treatment such as sieving or air flow classification in advance to remove fine powder of the catalyst, or installing a polymer removing device such as a filter in the polymerization process. It is said that there is a limit to removing fine powder only by such a physical treatment, and it is impossible to effectively reduce the fine powder polymer having a particle size of 200 μm or less.

The inventors of the present invention have conducted extensive research on the solid catalyst component and the polymerization method which can solve the above problems in the polymerization of olefins. As a result, the solid component produced by a simpler operation is dried and then fine powder is removed. And a powdery nonionic surfactant is added and mixed to obtain a solid catalyst component. From the solid catalyst component (A), the organoaluminum compound (B) and the specific organosilicon compound (C), When olefin polymerization was attempted in the presence of the formed catalyst, it was confirmed that it effectively functions to suppress the formation of finely divided polymer, and the yield of stereoregular polymer is maintained at a high level. .

The present invention was developed on the basis of the above findings, and its object is to provide a polyolefin having a particle shape close to spherical and containing almost no fine powder having a particle diameter of 200 μm or less and having excellent stereoregularity. An object of the present invention is to provide a solid catalyst component for olefin polymerization which can be obtained in high yield, and a method for polymerizing olefins using a catalyst containing the solid catalyst component.

[0012]

The solid catalyst component for olefin polymerization according to the present invention for achieving the above object comprises:
Spherical dialkoxymagnesium (a), aromatic hydrocarbon (b) and phthalic acid diester (c) that are liquid at room temperature
The volume ratio of the suspension formed by and the aromatic hydrocarbon (b) that is liquid at room temperature to the total amount of the aromatic hydrocarbon is 1 /
A first catalytic reaction step of obtaining a reaction product by adding it to a mixed solution of 2 or less of titanium tetrachloride (d) and then raising the temperature and reacting in a temperature range of 80 to 125 ° C. Aromatic hydrocarbons (b) that are washed with hydrocarbons and are liquid at room temperature
By volume ratio to the total amount of aromatic hydrocarbons in the presence of
80 to 125 ° C by adding titanium tetrachloride (d) of / 2 or less
After the second catalytic reaction step in which a solid component is produced by reacting in the temperature range of 1), and then the produced solid component is dried and subjected to fine powder removal treatment, the powdered nonionic surfactant (e) is added. The structural feature is that it is obtained through a treatment process of addition.

Among the components for preparing the solid catalyst component of the present invention, spherical dialkoxymagnesium [hereinafter sometimes simply referred to as "(a) substance"] includes diethoxymagnesium, dibutoxymagnesium and diphthoxide. Enoxymagnesium, di-n-propoxymagnesium,
Examples thereof include diisopropoxy magnesium, di-sec-butoxy magnesium, di-tert-butoxy magnesium and the like, but diethoxy magnesium is preferably used for the purpose of the present invention.

Toluene, xylene, ethylbenzene, propylbenzene, trimethylbenzene and the like are used as the aromatic hydrocarbon which is liquid at room temperature [hereinafter, may be simply referred to as "(b) substance"].

Phthalic acid diester [hereinafter, simply referred to as "(c)
Examples of the “substance” include, for example, dimethyl phthalate, diethyl phthalate, di-n-propyl phthalate, diisopropyl phthalate, di-n-butyl phthalate, diisobutyl phthalate, di-n-amyl phthalate, diisoamyl phthalate, ethyl-n. -Butyl phthalate, ethyl isobutyl phthalate, ethyl-n
-Propyl phthalate and the like.

The powdered nonionic surfactant [hereinafter sometimes simply referred to as "(e) substance"] includes 1,5-sorbitan ester and 1,4-sorbitan ester, and specifically, Examples thereof include sorbitan monolaurate, sorbitan monostearate, and sorbitan monooleate. Among them, 1,5-sorbitan monolaurate is preferably used. Since the substance (e) needs to be a powder at the time of use, it is used after being pulverized by a mechanical pulverizing means in the case of a lump.

The solid catalyst component for olefin polymerization of the present invention is prepared through a process consisting of a first catalytic reaction step, a second catalytic reaction step and a treatment step. In the first contact reaction step, a suspension is formed from the substances (a), (b) and (c), and the suspension is mixed with the substance (b) and titanium tetrachloride [hereinafter simply referred to as "(d) Sometimes referred to as “substance”] is added to the mixed solution to cause a catalytic reaction. The substance (a) and the substance (b) are mixed at an arbitrary ratio within the range where a suspension can be formed, and the substance (c) is 0.1 g for the substance (a) 1.0 g.
It is used in the range of 1 to 1.0 g. (D) The substance is
(B) The volume ratio to the total amount of the substance is 1/2 or less,
(A) The amount ratio is set to 1.0 g or more with respect to 1.0 g of the substance.

The formation of a suspension is usually at room temperature to (b)
At a temperature below the boiling point of the substance for 100 hours or less, preferably 1
It is performed with stirring within a time of 0 hours or less. The contact between the suspension and the mixed solution of the substance (b) and the substance (d) is performed at around room temperature, preferably in the temperature range of 5 to 30 ° C., while avoiding a rapid reaction between the two. It is preferable to consider Then, the temperature of the mixture is raised to 80
The reaction product is obtained by reacting in a temperature range of ~ 125 ° C for 10 minutes to 10 hours with stirring.

The second catalytic reaction step is a step of washing the above reaction product with an aromatic hydrocarbon and further adding the substance (d) in the presence of the substance (b) to cause a catalytic reaction. Even if the aromatic hydrocarbon used for washing is the same as the substance (b),
It does not matter if they are different. The washed reaction product is
In the presence of the substance (b), the reaction is carried out with the substance (d) whose volume ratio to the total amount of the substance (b) is 1/2 or less. The catalytic reaction is carried out in the temperature range of 80 to 125 ° C. for 10 minutes to 10 hours with stirring to produce a solid component.
The produced solid component is washed with an inert organic solvent such as n-heptane, if necessary.

Then, the solid component obtained in the second catalytic reaction step is dried into a powder form, subjected to fine powder removal treatment by means such as air stream classification, and then transferred to a treatment step of adding substance (e). At this time, the mixture is effectively mixed by adding with stirring, and becomes the solid catalyst component of the present invention.
The amount of the substance (e) added is arbitrarily set unless it adversely affects the performance of the solid catalyst component prepared.

A series of operations in each of the above steps must be performed in an atmosphere of an inert gas such as argon or nitrogen. There is no particular limitation on the means for contacting each of the above substances, and a container equipped with a stirrer is usually used.

The solid catalyst component for olefin polymerization of the present invention can be obtained through the above-mentioned steps, but each step does not require any special complicated treatment operation, and therefore can be smoothly prepared by an extremely simple process. . Of these, the first and second
The contact reaction step and treatment step of are important requirements of the present invention that have a delicate influence on the particle shape and particle size distribution of the produced polymer, and neglect the control of temperature, time, etc. during the contact reaction, or the liquid state before drying. Fine powder removal treatment with, or (e)
200 μm when no substance is added
It becomes impossible to obtain a polymer having an excellent particle shape and a sharp particle size distribution while effectively suppressing the following fine powder polymer.

The polymerization method according to the present invention comprises the solid catalyst component (A) for olefin polymerization obtained in the above step, the organoaluminum compound (B) and the general formula SiR _m (O 2
R ′) _{4 -m} (wherein R represents hydrogen, an alkyl group or an aryl group, R ′ represents an alkyl group or an aryl group, and m
Is 0 ≦ m ≦ 4. ) The olefin is polymerized or copolymerized in the presence of a catalyst consisting of the organosilicon compound (C).

As the organoaluminum compound (B),
Trialkylaluminums, dialkylaluminum halides, alkylaluminum dihalides or mixtures thereof are applied. Examples of the organosilicon compound (C) include phenylalkoxysilane and alkylalkoxysilane. Specific examples of the phenylalkoxysilane include phenyltrimethoxysilane, phenyltriethoxysilane, phenyl-n-propoxysilane, phenyltriisopropoxysilane, diphenyldimethoxysilane, and diphenyldiethoxysilane. As specific examples of, tetramethoxysilane, tetraethoxysilane, ethyltrimethoxysilane, methyltrimethoxysilane,
Examples thereof include methyltriethoxysilane, cyclohexylmethyldimethoxysilane, dicyclohexyldimethoxysilane, ethyltriisopropoxysilane and the like.

The amount ratio of each component used when forming the polymerization catalyst is such that the organoaluminum compound (B) is in a molar ratio of 5 to 1000 per mol of Ti atom in the solid catalyst component (A).
And the organosilicon compound (C) has a molar ratio of 0.002 to 0.5 per mole of the organoaluminum compound.

The homopolymerization or copolymerization of olefins according to the present invention is carried out in the presence of a polymerization catalyst having the above composition. The olefins to be polymerized are ethylene, propylene, 1-butene, 4-methyl-1-pentene, etc., the polymerization is carried out with or without an organic solvent, and the olefin monomer is either a gas or a liquid. It can also be used in the state of. The polymerization conditions are usually a polymerization temperature of 200 ° C.
Below, preferably below 100 ℃, polymerization pressure is 100kg / c
It is set to m ² · G or less, preferably 50 kg / cm ² · G or less.

[0027]

In the polyolefin produced by the polymerization method of the present invention, each particle has a shape close to a sphere and the surface is smooth and has a unique luster, and almost all finely divided polymer particles having a particle diameter of 200 μm or less are present. It has a sharp particle size distribution. In addition, the stereoregular polymer yield is high, the catalytic activity is high, and its durability is excellent. The manifestation of such an effect is obtained by drying the solid component produced through the catalytic reaction process, removing the fine powder, and then adding the nonionic surfactant powder to the solid catalyst component of the present invention prepared through the treatment process. It is presumed that it is caused based on the unique action of the polymerization method using the solid catalyst component.

[0028]

EXAMPLES The present invention will be specifically described below by comparing Examples with Comparative Examples.

Example 1 Preparation of solid catalyst component: After fully replacing the inside of a 500 ml round-bottomed flask equipped with a stirrer with nitrogen gas,
30 ml of toluene and 20 ml of titanium tetrachloride were added and stirred to form a mixed solution. Then, add this mixed solution to 20
While kept at .about.25.degree. C., a suspension prepared from 10 g of spherical diethoxymagnesium, 50 ml of toluene and 3.6 ml of di-n-butyl phthalate was added dropwise over a period of 4 hours. After the addition was completed, the temperature was raised to 90 ° C. and the reaction was carried out for 1 hour with stirring (first reaction).
Contact reaction step). After the reaction was completed, the reaction product was washed twice with 100 ml of toluene at a boiling point, and then 20 ml of titanium tetrachloride.
And 80 ml of toluene were added, and a catalytic reaction was carried out while stirring at 110 ° C. for 2 hours (second catalytic reaction step). The solid component thus produced was washed with 200 ml of n-heptane at 40 ° C. 10 times, and then dried until the residual ratio of heptane was 20% by weight or less to obtain a powdery solid component. The obtained powdery solid component is subjected to an air stream classifier [manufactured by Nisshin Engineering Co., Ltd.,
TC-15 type], fine powder having a particle size of 11 μm or less was removed, and 9.0 g of this solid component was pulverized in advance by a vibration mill for 30 minutes to give a powder of 1,5-sorbitan monolaurate (manufactured by Kao Corporation). 1.0 g of "Emazole S-20"] was added and mixed to obtain a solid catalyst component (treatment step). The titanium content in the prepared solid catalyst component was 2.53% by weight.

Formation of catalyst for polymerization and propylene polymerization: 0.0066 mmol of the above solid catalyst component as Ti atoms and 1 part of triethylaluminum were added to an autoclave equipped with a stirrer and having an internal volume of 2.0 l, which was completely replaced with nitrogen gas. .32 mmol and phenyltriethoxysilane 0.
13 mmol was added and stirred to form a polymerization catalyst.
Then, 1.8 liters of hydrogen gas and 1.4 liters of liquefied propylene were charged, and a polymerization reaction was carried out at 70 ° C. for 30 minutes.

Characteristic evaluation: Total weight of the obtained polymer, amount of insoluble polymer after extraction with boiling n-heptane for 6 hours, polymerization activity per solid catalyst component, yield of all crystalline polymer. Rate, MI of the produced polymer, average particle size of the produced polymer,
The amount of fine powder of the produced polymer was measured and evaluated, and the results are shown in Table 1. The polymerization activity and the yield of the total crystalline polymer per solid catalyst component are shown as values according to the following formulas (1) and (2), respectively.

[0032]

[0033]

Example 2 In the treatment step, 1 was added to 9.5 g of the powdery solid component.
A polymerization catalyst was formed under the same conditions as in Example 1 except that 0.5 g of 5-sorbitan monolaurate was added, and a polymerization test was conducted. At this time, the titanium content in the solid catalyst component was 2.76% by weight. The results of characteristic evaluation of the obtained polymer are also shown in Table 1.

Example 3 In the treatment step, 1 was added to 8.5 g of the powdery solid component.
A polymerization catalyst was formed under the same conditions as in Example 1 except that 1.5 g of 5-sorbitan monolaurate was added, and a polymerization test was conducted. At this time, the titanium content in the solid catalyst component was 2.50% by weight. The results of characteristic evaluation of the obtained polymer are also shown in Table 1.

Example 4 In the treatment step, 1 was added to 9.9 g of the powdery solid component.
A polymerization catalyst was formed under the same conditions as in Example 1 except that 0.1 g of 5-sorbitan monolaurate was added, and a polymerization test was conducted. At this time, the titanium content in the solid catalyst component was 2.75% by weight. The results of characteristic evaluation of the obtained polymer are also shown in Table 1.

Comparative Example 1 A nonionic surfactant was not added in the treatment step and the other conditions were the same as in Example 1 to form a polymerization catalyst,
A polymerization test was conducted. The titanium content in the solid catalyst component at this time was 2.78% by weight. The evaluation results of the properties of the obtained polymer are also shown in Table 1.

[0038]

[Table 1]

From the results shown in Table 1, the polymer obtained by the polymerization method of the present invention using the polymerization catalyst containing the solid catalyst component for olefin polymerization of the present invention has a particle size of 200 μm or less as compared with that of the comparative example. The amount of finely divided polymer was clearly reduced, and the amount was almost absent. In addition, it was confirmed that the particle shape of the produced polymer was almost spherical, and the particle size distribution was arranged within a narrow range. Moreover, it was confirmed that the polymerization activity per solid catalyst component and the yield of the stereoregular polymer were maintained at a high level.

[0040]

As described above, according to the present invention, a solid catalyst component for olefin polymerization obtained through a catalytic reaction step and a treatment step by a specific simplified method and a polymerization method using a polymerization catalyst containing the same , The particle shape is almost spherical, and the surface has a unique luster, and the particle size is 200 μm.
It is possible to obtain a polyolefin powder having a narrow particle size distribution in which the following fine powder polymer is scarcely present. Therefore, the fluidity is excellent, and troubles such as blockage of pipes that cause an operation stop during pipe transportation are eliminated. Further, the presence of the finely divided polymer lowers the bulk specific gravity and reduces the polymerization reaction efficiency,
This problem is solved at the same time, and the post-treatment process of the produced polymer is facilitated, which greatly contributes to cost reduction due to improvement of operation efficiency and energy saving.

Further, in order to maintain the excellent performance in the yield of the stereoregular polymer, the high polymerization activity and the sustainability thereof, the catalyst residue remaining in the produced polymer is reduced to a negligible amount, and It also exhibits the effect of being sufficiently adaptable to a long-term polymerization reaction such as that of a block copolymer. Therefore, excellent practicality is expected as a solid catalyst component for polymerization and a polymerization method for industrial production of polyolefin having a wide range of applications.

[Brief description of drawings]

FIG. 1 is a schematic flowchart illustrating the configuration of the present invention.

Claims (2)

[Claims] 1. A suspension formed of spherical dialkoxymagnesium (a), an aromatic hydrocarbon (b) that is liquid at room temperature and a phthalic acid diester (c) is used as an aromatic hydrocarbon (liquid that is liquid at room temperature). The mixture is added to a mixed solution of b) and titanium tetrachloride (d) whose volume ratio to the total amount of the aromatic hydrocarbon is 1/2 or less, and then the temperature is raised, and the mixture is reacted in a temperature range of 80 to 125 ° C. to generate reaction. The first catalytic reaction step for obtaining a product, the reaction product is washed with an aromatic hydrocarbon, and further, in the presence of the aromatic hydrocarbon (b) which is liquid at room temperature, the volume ratio to the total amount of the aromatic hydrocarbon is 1 / 2 or less titanium tetrachloride (d) is added and reacted in a temperature range of 80 to 125 ° C to produce a solid component, and then the produced solid component is dried to remove fine powder. After applying, powdered nonionic surfactant ( A solid catalyst component for olefin polymerization, which is obtained through a treatment step of adding e). 2. The solid catalyst component (A) for olefin polymerization according to claim 1, an organoaluminum compound (B) and a general formula SiR _m (OR ′) _4-m (wherein R is hydrogen or an alkyl group). Or an aryl group, R'represents an alkyl group or an aryl group, and m is 0≤m≤4), and olefin is polymerized or copolymerized in the presence of a catalyst consisting of an organosilicon compound (C) represented by A method for polymerizing olefins, comprising: