JP2525157B2 - Solid catalyst component for olefin polymerization - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention has a high activity when subjected to the polymerization of olephins, and is capable of obtaining a stereoregular polymer in a high yield. It relates to a performance catalyst. More specifically, the present invention relates to a magnesium compound having a magnesium-carbon bond, which is obtained by reacting metallic magnesium powder with a chloride of an aliphatic hydrocarbon which is liquid at room temperature in the presence of iodine in the absence of a solvent. The present invention relates to a solid catalyst component obtained by bringing TiCl ₄ into contact with a product obtained by co-grinding phthalic acid with a diester of phthalic acid.

[Prior art]

Recently, as a catalyst for the polymerization of olefins such as propylene, in place of the conventionally known catalyst component of titanium trichloride, many new types of catalysts in which titanium, which is an active component, is supported on magnesium chloride together with an electron donor have been developed. Proposed.

The earliest of these was developed by co-milling a complex of an organic monocarboxylic acid ester as an electron donor and titanium tetrachloride with magnesium chloride, or an organic monocarboxylic acid as an electron donor. There is a product obtained by treating a co-ground product of an acid ester and magnesium chloride with titanium tetrachloride.

However, they cannot be said to have satisfactory properties for use on an industrial scale, and those which improve various properties, for example, diethoxymagnesium instead of magnesium chloride, and special electron donors are used. Various proposals have been made for those using a compound, or those obtained by modifying the combination method of the above-mentioned substances, the contact means and the like.

For example, in JP-A-54-94590, a catalyst component is prepared by using magnesium dihalide as a starting material, and an organoaluminum compound, an organic carboxylic acid ester and M
A method of combining a compound having a —O—R group and the like for use in the polymerization of olefins is disclosed, and JP-A-57-
In 63310, various catalysts as electron donors, magnesium chloride in active form, and a titanium compound are combined to prepare a catalyst component, and further Si—O bond or Si—
A method for polymerizing propylene using a compound having an N bond and an organoaluminum compound is disclosed.

[Problems to be solved by the invention]

In the prior art, chlorine contained in magnesium chloride, which occupies the main stream as a carrier material, has a drawback that it adversely affects the produced polymer, like the halogen element in titanium halides. On the other hand, it is required that the activity of chlorine be substantially negligible, or that the concentration of magnesium chloride itself be kept low.

Further, when a catalyst component having the above magnesium chloride as a carrier is used in combination with an organoaluminum compound to polymerize olefins, particularly when stereoregular polymerization of propylene, 1-butene, etc. is carried out industrially, when carrying out the polymerization reaction. It is essential to use an organic monocarboxylic acid ester as an electron donor. However, in this case, it is necessary to use an extremely large amount of organic monocarboxylic acid ester, and as a result, there has been a problem that a peculiar ester odor is imparted to the produced polymer.

Furthermore, in so-called highly active supported catalysts such as catalysts using a catalyst component having magnesium chloride as a carrier, the activity at the initial stage of polymerization is high, but deactivation with time is large and it becomes a problem in process operation, and block copolymerization It was virtually impossible to use it if the polymerization time was longer.

JP-A-54-94590 has been proposed to improve this point, but as is clear from the description of the publication, in this case, an organic carboxylic acid ester is used both during catalyst preparation and during polymerization. Is needed.
Generally, the organic carboxylic acid ester contained in the catalyst is
By treatment with titanium halide or washing with an organic solvent, the amount of odor of the produced polymer is negligible. However, the organic carboxylic acid ester used during the polymerization is extremely large amount as compared with the amount contained in the catalyst as described above, and when the polymerization is carried out in a liquid or gaseous monomer, almost all of it is At present, it is contained in the produced polymer, and therefore, the problem of the odor of the produced polymer cannot be solved as long as an organic carboxylic acid ester is used during the polymerization. Further, as can be seen from the examples, the method disclosed in the above publication requires extremely complicated operations and the obtained catalyst is practically sufficient in terms of performance and sustainability of activity. That is not the case.

The present inventors have conducted intensive studies to solve the problems remaining in the conventional techniques, and as a result, have succeeded in providing a novel solid catalyst component for polymerization of olefins according to the present invention.

[Means for solving problems]

According to the present invention, (a) a magnesium-carbon bond obtained by reacting a metal magnesium powder with a chloride of an aliphatic hydrocarbon that is liquid at a room temperature of 2 times or more in the presence of iodine in the absence of a solvent is used. The obtained magnesium compound and (b) a diester of phthalic acid were co-ground to obtain a composition (c) TiCl
_A solid catalyst component for polymerization of olefins, which is obtained by bringing ( ₄ ) into contact with ( ₄ ) TiCl _{4 and then} contacting the obtained reaction product, is provided.

A magnesium compound having a magnesium-carbon bond (hereinafter simply referred to as a substance (a)) obtained by the reaction of the metal magnesium powder (a) in the present invention with a chloride of an aliphatic hydrocarbon that is liquid at room temperature is obtained. The commercially available metal magnesium powder is reacted with a chloride of an aliphatic hydrocarbon that is liquid at room temperature in the presence of iodine in the absence of an organic solvent. It is necessary to use 2 mol or more of the chloride in 1 mol of the magnesium metal powder. The reaction temperature and the reaction time are arbitrary as long as the above reaction proceeds sufficiently, and are not particularly limited, but are usually 20 ° C. or higher and 10 minutes or longer,
It is preferably carried out at 40 ° C. or higher for 30 minutes or longer. This reaction is a Grineer type reaction, and the absorption of an alkyl group is observed when the IR spectrum of the substance (a) obtained by the reaction is measured.

Examples of chlorides of aliphatic hydrocarbons that are liquid at room temperature and are used in the production of the substance (a) include, for example, n-propyl chloride, isopropyl chloride, n-butyl chloride, isobutyl chloride, pentyl chloride, hexyl chloride and octyl chloride. Can be given.

Examples of the (b) phthalic acid diester in the present invention include dimethyl phthalate, diethyl phthalate, diisopropyl phthalate, dipropyl phthalate, dibutyl phthalate, diisobutyl phthalate, diamyl phthalate, diisoamyl phthalate, ethyl butyl phthalate, ethyl isobutyl phthalate and ethyl. Propyl phthalate etc. can be mentioned as an example.

When obtaining the solid catalyst component in the present invention, the use ratio of each raw material constituting the solid catalyst component is arbitrary and is not particularly limited as long as it does not adversely affect the performance of the produced solid catalyst component. However, the amount of the diester of phthalic acid of the above (b) (hereinafter sometimes simply referred to as the (b) substance) is in the range of 0.01 to 1 g per 1 g of the (a) substance, and TiCl ₄ (of the above (c)) ( Hereinafter, it may be simply referred to as (c) substance) in the range of 0.1 g or more, preferably 1 g or more.

The co-milling of the substance (a) and the substance (b) is usually 10
It is carried out for not less than 1 minute and preferably not less than 30 minutes.

The contact between the composition obtained by the co-milling and the substance (c) is usually carried out in the temperature range from -10 ° C to the boiling point of the substance (c) for 10 minutes to 100 hours.

It is necessary to repeatedly contact the substance (c) with the composition obtained after the above contact, and the obtained composition can also be washed with an organic solvent such as n-heptane. These are all included in one aspect in the practice of the present invention.

The series of operations for preparing the solid catalyst component in the present invention is preferably carried out in the absence of oxygen and water.

The solid catalyst component prepared as described above is combined with an electron donating compound other than an aromatic carboxylic acid such as a piperidine derivative or an organosilicon compound having a Si-O bond and an organoaluminum compound to give a catalyst for olefin polymerization. Configure.

As the organoaluminum compound used here, trialkylaluminum is preferably used in an amount of 1 to 1000 mol per g atom of titanium in the solid catalyst component, and the electron donating compound is 1 or less in molar ratio to the organoaluminum compound, preferably Is used in the range of 0.005 to 1.0.

The polymerization reaction using the catalyst for polymerization according to the present invention can be carried out in the presence or absence of an organic solvent, and the olefin monomer used can be used in either gas or liquid state. it can. Polymerization temperature is 20
0 ℃ or less, preferably 100 ℃ or less, the polymerization pressure is 100kg /
cm ² · G or less, preferably 50 kg / cm ² · G or less.

The olefins homopolymerized or copolymerized using the solid catalyst component for olefin polymerization according to the present invention are ethylene, propylene, 1-butene and the like.

〔The invention's effect〕

When olefins are polymerized using the solid catalyst component for olefin polymerization according to the present invention, the polymer produced has extremely high stereoregularity. In addition, since the solid catalyst component exhibits an unexpectedly high activity, the amount of catalyst residue present in the produced polymer can be suppressed to a very low level, and the residual chlorine content is extremely small, so the product Can reduce the effect of chlorine to the extent that no decalcification step is required.

Since chlorine remaining in the produced polymer causes corrosion of equipment used in steps such as granulation and molding, it also causes deterioration of the produced polymer itself, yellowing, etc. Obtaining is of great benefit to the art.

Further, according to the present invention, by not adding the organic carboxylic acid ester at the time of the polymerization, it is possible to solve the big problem that the ester odor adheres to the produced polymer.

Further, conventionally, there was a common defect in so-called highly active supported catalysts, in which the activity per unit time of the catalyst was significantly reduced with the progress of polymerization, but the solid catalyst component according to the present invention was used. In the catalyst obtained by the above, the decrease in activity with the passage of polymerization time is extremely small as compared with conventionally known catalysts, and therefore it is useful even when the polymerization time such as copolymerization is made longer, and Since a large increase in activity is obtained when a higher polymerization pressure is adopted, it can be widely used in bulk polymerization and gas phase polymerization, which have recently received attention.

In addition, in the industrial production of olefin polymers, coexistence of hydrogen at the time of polymerization is generally considered from the viewpoint of MI control and the like, but conventional magnesium chloride is used as a carrier and organic carboxylic acid ester is used. The catalyst had a drawback that its activity and stereoregularity were significantly reduced in the presence of hydrogen. However, when olefin polymerization is carried out in the coexistence of hydrogen using the catalyst of the present invention,
The activity and stereoregularity are not reduced even when the MI of the produced polymer is extremely high. Such an effect has been strongly desired by those skilled in the art. In addition, in industrial production of polyolefin, the bulk specific gravity of the produced polymer becomes a very large problem in terms of the capacity of the polymerization apparatus, the capacity of the post-treatment step, and the like, but the catalyst according to the present invention also has this problem. And has extremely excellent characteristics.

[Examples and Comparative Examples]

Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples.

Example 1 (1) (a) Preparation of Material Using a round bottom flask with a volume of 2.0 equipped with a stirrer,
After thoroughly replacing it with nitrogen gas, 30 g of magnesium metal powder, 1.0 g of iodine and 1.2 g of n-butyl chloride were added.
And reacted at the boiling point of n-butyl chloride for 5 hours. After the reaction was completed, the supernatant was removed and the product was added to 500 ml.
After being washed with n-butyl chloride for 3 times, it was dried under reduced pressure to obtain a powdery substance (a).

(2) Preparation of solid catalyst component 30 g of the powdery substance obtained in (1) above and 7.0 ml of dibutyl phthalate were filled in a nitrogen gas atmosphere with a stainless steel ball of 25 mmφ 4/5 of the total volume, and a vibration mill pot with a capacity of 1.0. At a vibration frequency of 1430 V ・ p ・ m and an amplitude of 3.5 mm
It was crushed for 24 hours.

Using a round bottom flask with a capacity of 500 ml equipped with a stirrer,
After thoroughly substituting with nitrogen gas, 5 g of the solid composition obtained by the above-mentioned pulverization treatment was taken, and TiCl ₄ 200 ml
Was added, the temperature was raised to 115 ° C., and the reaction was performed for 2 hours. After completion of the reaction, the supernatant was removed, 200 ml of TiCl ₄ was newly added to the product, and the reaction was carried out at 115 ° C for 2 hours. After completion of the reaction, the mixture was cooled to 40 ° C., and the product was washed 10 times with 200 ml of n-heptane to obtain a solid catalyst component.

At this time, the titanium content in the solid catalyst component was measured and found to be 1.69% by weight.

(3) Polymerization Using an autoclave equipped with a stirrer and having an internal volume of 2.0, this was completely replaced with nitrogen gas, and then 193 mg of triethylaluminum, 24 mg of 2,2,6,6-tetramethylpiperidine and 6.0 mg of the above solid catalyst component. Charged. Then, 1.8 ml of hydrogen gas and 1.4 of liquefied propylene were charged, and the polymerization reaction was carried out at 70 ° C. for 1 hour. After the completion of the polymerization reaction, the produced polymer is dried under reduced pressure at 80 ° C., and the amount of the obtained product is designated as (A). Further, this product was extracted with boiling n-heptane for 6 hours to obtain a polymer insoluble in n-heptane, and the amount of this product is designated as (B).

The polymerization activity (C) per the solid catalyst component used is represented by the following formula.

The yield (D) of all crystalline polymer is represented by the following formula.

Further, the residual chlorine content in the produced polymer is represented by (E), the MI of the produced polymer is represented by (F), and the bulk specific gravity is represented by (G). The obtained results are shown in Table 1.

Example 2 An experiment was conducted in the same manner as in Example 1 except that the polymerization time was 30 minutes. The obtained results are as shown in Table 1.

Example 3 An experiment was carried out in the same manner as in Example 1 except that the polymerization reaction was carried out by the following method.

700 ml of n-heptane was charged into an autoclave with a stirrer and an internal volume of 2.0, which was completely replaced with nitrogen gas.
g, 2,2,6,6-tetramethylpiperidine 37 mg, and then 14.0 mg of the solid catalyst component prepared by the method of Example 1 were charged.
After that, 150 ml of hydrogen gas was charged, the temperature was raised to 70 ° C, and propylene gas was introduced, while maintaining a pressure of 6 kg / cm ² · G.
The polymerization reaction was performed for a time. After the completion of the polymerization reaction, the obtained solid polymer was separated, heated to 80 ° C., and dried under reduced pressure. On the other hand, the amount of the polymer dissolved in the polymerization solvent by condensing the liquid is defined as (H), and the amount of the solid polymer is defined as (I). Further, the obtained solid polymer was extracted with boiling n-heptane for 6 hours,
A polymer insoluble in n-heptane was obtained, and this amount is designated as (J).

The polymerization activity (K) per solid catalyst component is represented by the following formula.

Further, the yield (L) of the crystalline polymer is represented by the following formula, The yield (M) of the whole crystalline polymer is determined by the following equation.

Further, residual chlorine in the produced polymer is represented by (N), MI of the produced polymer is represented by (O), and bulk specific gravity is represented by (P). The results obtained are shown in Table 2.

Example 4 An experiment was performed in the same manner as in Example 3, except that the polymerization time was changed to 2 hours. The results obtained are shown in Table 2.

Example 5 An experiment was conducted in the same manner as in Example 1 except that the same amount of dipropyl phthalate was used instead of dibutyl phthalate. The titanium content in the solid catalyst component at this time was 1.
It was 78% by weight. An experiment was conducted in the same manner as in Example 1 during the polymerization. The results obtained are as shown in Table 1.

Example 6 A solid catalyst component was prepared in the same manner as in Example 1 except that 8.5 ml of dibutyl phthalate was used instead of 7.0 ml of dibutyl phthalate. The titanium content in the solid catalyst component was 2.11% by weight. An experiment was conducted in the same manner as in Example 1 during the polymerization. The results obtained are as shown in Table 1.

Comparative Example 1 20 g of commercially available MgCl ₂ and 5.0 ml of dibutyl phthalate were ground under the same conditions as in Example 1. Then, 5 g of the pulverized composition was charged into a glass container having an internal volume of 500 ml under a nitrogen gas atmosphere, 200 ml of TiCl ₄ was added, and a stirring reaction was carried out at 120 ° C. for 2 hours. After completion of the reaction, the supernatant was removed, 200 ml of TiCl ₄ was newly added, and the reaction was carried out at 120 ° C for 2 hours.

After completion of the reaction, it was cooled to 40 ° C. and washed 10 times with 200 ml of n-heptane to obtain a solid catalyst component. At this time, the titanium content in the solid catalyst component was measured and found to be 1.64% by weight.

An experiment was conducted in the same manner as in Example 1 except that 6.0 mg of the above solid catalyst component was used for the polymerization. The results obtained are as shown in Table 1.

Comparative Example 2 An experiment was conducted in the same manner as in Comparative Example 1 except that the polymerization time was 30 minutes. The results obtained are as shown in Table 1.

Comparative Example 3 An experiment was performed in the same manner as in Comparative Example 1 except that the polymerization reaction was performed in the same manner as in Example 3. The results obtained are shown in Table 2.

As is clear from comparison between Examples 1 and 2 and Comparative Examples 1 and 2, the catalyst according to the present invention has an extremely small decrease in activity with the passage of polymerization time.

As is clear from comparison between Examples 1 and 3 and Comparative Examples 1 and 3, the catalyst according to the present invention shows a large increase in activity when a higher polymerization pressure is adopted.

[Brief description of drawings]

FIG. 1 is a schematic drawing for helping understanding of the present invention.

Claims (1)

(57) [Claims] 1. A magnesium-obtained by reacting (a) metallic magnesium powder with a chloride of an aliphatic hydrocarbon that is liquid at room temperature in a molar ratio of 2 times or more in the absence of a solvent and in the presence of iodine. A magnesium compound having a carbon bond,
(B) a composition obtained by co-milling with a diester of phthalic acid is brought into contact with (c) TiCl ₄ , and the obtained reaction product is further brought into contact with (c) TiCl _4. A characteristic solid catalyst component for polymerization of olefins.