JPH0667976B2 - Olefin polymerization catalyst - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention has a high activity when it is subjected to the polymerization of olefins and has a high activity, and a stereoregular polymer can be obtained in an extremely high yield. The catalyst, more specifically, a catalyst component for polymerization of olefins obtained by contacting aluminum stearate, dialkoxy magnesium, diester of aromatic dicarboxylic acid, halogenated hydrocarbon, and titanium halide, a silicon compound and an organic aluminum compound The present invention relates to a catalyst for olefin polymerization, which comprises

[Conventional technology]

Conventionally, as a catalyst for olefin polymerization having high activity, a combination of a solid titanium halide as a catalyst component and an organoaluminum compound is well known and widely used. Since the yield of the polymer per titanium (hereinafter referred to as the catalyst component and the polymerization activity per titanium in the catalyst component) was low, a so-called deashing step for removing the catalyst residue was unavoidable. Since this deashing process uses a large amount of alcohol or a chelating agent, a recovering device or a regenerating device for them is indispensable, and there are many resources, energy, and other incidental problems, and those skilled in the art can quickly solve the problem. This is an important issue that is desired. In order to eliminate this complicated deashing step, many studies have been made and proposed to increase the polymerization activity per catalyst component, especially titanium per catalyst component.

In particular, as a recent tendency, a transition metal compound such as titanium halide, which is an active component, is supported on a carrier substance such as magnesium chloride, and when subjected to the polymerization of olefins, the polymerization activity per titanium in the catalyst component is dramatically increased. There are many proposals to raise the price.

[Problems to be solved by the invention]

However, the chlorine contained in magnesium chloride, which forms the mainstream as a carrier substance, has a drawback that it has an adverse effect on the produced polymer as well as the halogen element in titanium halides. Therefore, the effect of chlorine is virtually ignored. There was an unsolved part such as a high activity required, or the need to keep the concentration of magnesium chloride itself low.

The present inventors have aimed to reduce residual chlorine in the produced polymer while maintaining the polymerization activity per catalyst component and the yield of the stereoregular polymer at a high level.
In 107, a method for producing a catalyst component for polymerization of olefins was proposed, and the initial purpose was achieved.

However, in the case of using the above-mentioned catalyst component having magnesium chloride as a carrier, or the catalyst component obtained in the above-mentioned JP-A-59-91107, the polymerization activity per unit time is high at the beginning of the polymerization, but decreases with the passage of the polymerization time. It is large and becomes a problem in process operation, and when it is necessary to prolong the polymerization time such as block copolymerization, it is practically impossible to use.

The present inventors have achieved the present invention as a result of earnest research in order to solve the problems left over in the prior art and to further improve the quality of the polymer produced.

[Means for solving problems]

That is, the features of the present invention are: (A) (a) aluminum stearate, (b) dialkoxymagnesium, (c) diester of aromatic dicarboxylic acid, (d) halogenated hydrocarbon, and (e) A titanium halide represented by the general formula TiX ₄ (where X is a halogen element) (hereinafter, may be simply referred to as titanium halide) is contacted with a composition obtained by contacting the composition twice more, and A catalyst component obtained by contacting with a titanium halide; (B) a general formula SiRm (OR ') _4-m (wherein R is hydrogen, an alkyl group or an aryl group, and R'is an alkyl group or an aryl group; , M is 0 ≦ m ≦ 4) (hereinafter, sometimes simply referred to as a silicon compound); and (C) an organoaluminum compound-containing polyolefin. It is to provide a class polymerization catalyst.

As dialkoxy magnesium used in the present invention, diethoxy magnesium, diptoxy magnesium, diphenoxy magnesium, dipropoxy magnesium, di-sec-ptoxy magnesium, di-tert-
Examples thereof include putoxy magnesium, diisopropoxy magnesium, etc. Among them, diethoxy magnesium and dipropoxy magnesium are preferable.

The aluminum stearate and dialkoxymagnesium are preferably used in the form of water removed as much as possible.

The aromatic dicarboxylic acid diester used in the present invention is preferably a phthalic acid or terephthalic acid diester, for example, dimethyl phthalate, dimethyl terephthalate, diethyl phthalate, diethyl terephthalate, dipropyl phthalate, dipropyl terephthalate, diptyl phthalate, Examples thereof include diptyl terephthalate, diisobutyl phthalate, diamyl phthalate, diisoamyl phthalate, ethylbutyl phthalate, ethyl isobutyl phthalate and ethyl propyl phthalate.

The halogenated hydrocarbon used in the present invention is preferably a chloride of an aromatic or aliphatic hydrocarbon which is liquid at room temperature, and examples thereof include propyl chloride, butyl chloride, butyl promide, propyl iodide, o-dichlorobenzene and benzyl. Examples thereof include chloride, dichloroethane, trichloroethylene, dichlorobropane, dichlorobenzene, trichloroethane, carbon tetrachloride, chloroform and methylene chloride. Among them, o-dichlorobenzene, propyl chloride, dichloroethane, chloroform, carbon tetrachloride, and chloride Methylene is preferred.

Examples of the titanium halide represented by the general formula TiX ₄ (where X is a halogen element) used in the present invention include TiCl ₄ , TiBr ₄ , TiI _{4 and the} like.
l ₄ is preferred.

As the silicon compound used in the present invention,
Examples thereof include phenylalkoxysilane and alkylalkoxysilane. Further examples of phenylalkoxysilanes include phenyltrimethoxysilane, phenyltriethoxysilane, phenyltripropoxysilane, phenyltriisopropoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, and the like. Examples of the alkylalkoxysilane include tetramethoxysilane, tetraethoxysilane, trimethoxyethylsilane, trimethoxymethylsilane, triethoxymethylsilane, ethyltriethoxysilane, and ethyltriisopropoxysilane.

Examples of the organoaluminum compound used in the present invention include trialkylaluminums, dialkylaluminum halides, alkylaluminum dihalides, and mixtures thereof.

When obtaining the catalyst component in the present invention, the use ratio of each raw material, the contact conditions, and the like are arbitrary and are not particularly limited, as long as they do not adversely affect the performance of the catalyst component to be produced. With respect to a total of 1 g of aluminum acid salt and dialkoxymagnesium, the diester of aromatic dicarboxylic acid is in the range of 0.01 to 2 g, preferably 0.1 to 1 g, and the titanium halide is 0.1 g or more, preferably
It is in the range of 1 g or more. Further, the halogenated hydrocarbon is used in an arbitrary ratio, but is preferably an amount capable of forming a suspension.

At this time, the contact order and contact method of each raw material forming the catalyst component are not particularly limited, but as the first embodiment, the composition obtained after pulverizing aluminum stearate and dialkoxymagnesium, Obtained after contacting with a diester of an aromatic dicarboxylic acid and a titanium halide in the presence of a halogenated hydrocarbon, or as a second embodiment, crushing the diester of aluminum stearate, dialkoxymagnesium and an aromatic dicarboxylic acid. It is preferred to contact the composition with a titanium halide in the presence of a halogenated hydrocarbon.

The pulverization of aluminum stearate and dialkoxymagnesium in the first embodiment is usually carried out for 5 minutes or more using a ball mill, a vibration mill or the like, and the obtained composition and diester of aromatic dicarboxylic acid and titanium halide are mixed. The contacting is carried out in the presence of a halogenated hydrocarbon in the temperature range from 0 ° C. to the boiling point of the titanium halide usually used for 5 minutes to 100 hours.

The grinding of the aluminum stearate, dialkoxymagnesium and the diester of aromatic dicarboxylic acid in the second embodiment is usually carried out for 5 minutes or more using a ball mill, a vibration mill or the like to obtain the composition and titanium halide. The contacting is carried out in the presence of a halogenated hydrocarbon in the temperature range from 0 ° C. to the boiling point of the titanium halide usually used for 5 minutes to 100 hours.

The composition obtained after the contact of the respective components constituting the catalyst component is contacted with the titanium halide by repeating twice more. The contact conditions at this time are the same as the contact conditions with the first titanium halide. , After the contact treatment is completed, n-
It is also possible to wash with an organic solvent such as heptane.

It is preferable that these series of operations in the present invention are performed in the absence of oxygen and water.

The catalyst component produced as described above has broad peaks near 2θ = 32 ° and around 50 ° in its X-ray spectrum, and in combination with the silicon compound and the organoaluminum compound, a catalyst for olefin polymerization is obtained. Form. The organoaluminum compound used is used in a range of 1 to 1000 in molar ratio per mole of titanium atom in the catalyst component, and the silicon compound is 1 or less in molar ratio per mole of organoaluminum compound, preferably 0.005 to 0.5. Used in the range of.

The polymerization can be carried out in the presence or absence of an organic solvent, and the olefin monomer can be used in either gas or liquid state. Polymerization temperature is 200
℃ or less, preferably 100 ℃ or less, the polymerization pressure is 100kg /
cm ² · G or less, preferably 50 kg / cm ² · G or less.

Olefins homopolymerized or copolymerized using the catalyst component of the present invention are ethylene, propylene, 1-butene and the like.

〔The invention's effect〕

When the olefins are polymerized using the catalyst obtained according to the present invention, the resulting polymer has extremely high stereoregularity and, of course, has a very high activity, so that the catalyst in the resulting polymer is The residue can be kept extremely low,
Moreover, since the amount of residual chlorine is so negligible that no deashing step is required at all, the effect of chlorine on the produced polymer can be substantially eliminated.

Chlorine contained in the generated polymer causes corrosion of equipment used in processes such as granulation and molding, and also causes deterioration of the generated polymer itself, yellowing, etc., which can be substantially eliminated. This is extremely important to those skilled in the art.

Further, a feature of the present invention is that the activity of the catalyst component per unit time is significantly reduced with the progress of polymerization,
It is an object of the present invention to solve the essential drawbacks of so-called highly active supported catalysts and to provide a catalyst that can be practically applied not only to homopolymerization but also to copolymerization.

Further, in 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 the catalyst component using magnesium chloride as a carrier is active in the presence of hydrogen. And the stereoregularity is significantly reduced. However, when the olefins are polymerized in the presence of hydrogen using the catalyst component and the catalyst obtained according to the present invention, almost no activity and stereoregularity are obtained even when the MI of the produced polymer is extremely high. Does not decrease, and such an effect brings an extremely great benefit to those skilled in the art.

〔Example〕

 The present invention will be specifically described below with reference to examples.

Example 1 [Preparation of catalyst component] 5 g of aluminum stearate and 45 g of diethoxymagnesium were charged in a nitrogen gas atmosphere into a vibrating mill pot having a capacity of 1.0 liter filled with 25 mm stainless steel balls in a total volume of 4/5. , Frequency 1430v.pm and amplitude 3.5mm 1
The grinding treatment was performed at room temperature for an hour. In a round-bottomed flask with a capacity of 500 ml, fully replaced with nitrogen gas and equipped with a stirrer,
5.5 g of the composition obtained by the pulverization treatment and 15 ml of o-dichlorobenzene were taken, 1.8 ml of dibutyl phthalate and 200 ml of TiCl ₄ were added with stirring, and the temperature was raised to 110 ° C.
The reaction was carried out with stirring for an hour. After completion of the reaction, wash with 200 ml of n-heptane at 40 ° C. 10 times, and newly use 200 ml of TiCl _4.
After washing once at 40 ℃, add 200ml of TiCl ₄ and add 110
The reaction was carried out while stirring at 0 ° C for 2 hours.

After the reaction was completed, it was cooled to 40 ° C, and then 200 ml of n-heptane
The cleaning was repeated, and when chlorine was not detected in the cleaning liquid, the cleaning was completed and the catalyst component was used. At this time, the solid content of the catalyst component was separated, and the titanium content in the solid content was measured and found to be 2.35% by weight.

〔polymerization〕

700 ml of n-heptane was charged into an autoclave with a stirrer having an internal volume of 20 l which was completely replaced with nitrogen gas, and 301 mg of triethylaluminum, 64 mg of phenyltriethoxysilane and then the above catalyst components were added while maintaining a nitrogen gas atmosphere. 0.3 mg of titanium atom was charged. Then 120 ml of hydrogen gas
6k while charging propylene gas and raising the temperature to 70 ° C and introducing propylene gas
Polymerization was carried out for 4 hours while maintaining the pressure of g / cm ² · G.
After completion of the polymerization, the solid polymer obtained 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 (A), and the amount of the solid polymer is (B). Also, the obtained solid polymer was heated to 6 with boiling n-heptane.
It is extracted with time to obtain a polymer insoluble in n-heptane, and this amount is designated as (C).

The polymerization activity (D) per catalyst component is calculated by the formula Express with.

Further, the yield (E) of the crystalline polymer is calculated by the formula The yield (F) of all crystalline polymer is expressed by I asked more. Residual chlorine in the produced polymer is represented by (G) and MI of the produced polymer is represented by (H). The results obtained are the first
As shown in the table.

Example 2 An experiment was conducted in the same manner as in Example 1 except that the polymerization time was 6 hours. The results obtained are as shown in Table 1.

Example 3 An experiment was conducted in the same manner as in Example 1 except that 1.4 g of dipropyl phthalate was used. The titanium content in the solid content at this time was 269% by weight. An experiment was carried out in the same manner as in Example 1 except that 70 mg of phenyltriethoxysilane was used in the polymerization. The results obtained are as shown in Table 1.

Example 4 A catalyst component was prepared in the same manner as in Example 1 except that the reaction temperature was 120 ° C. The titanium content in the solid content at this time was 2.16% by weight. An experiment was conducted in the same manner as in Example 1 during the polymerization. The result obtained is the first
As shown in the table.

Example 5 Aluminum stearate 5 g, diethoxy magnesium
45 g and dipropyl phthalate 15 g were ground as in Example 1. 6 g of the obtained composition was placed in a round bottom flask having a capacity of 500 ml, which was sufficiently replaced with nitrogen gas and equipped with a stirrer, charged with 15 ml of o-dichlorobenzene and 200 ml of TiCl ₄ and heated to 110 ° C. The reaction was carried out with stirring for 2 hours. After completion of the reaction, it was washed 10 times with 200 ml of n-heptane at 40 ° C., and once again with 200 ml of Ticl ₄ at 40 ° C., 200 ml of TiCl ₄ was further added, and the mixture was stirred and reacted at 90 ° C. for 2 hours. After the reaction is complete, cool to 40 ° C, and add n-heptane.
The washing with 200 ml was repeated, and when no chlorine was detected in the washing liquid, the washing was completed and the catalyst component was obtained. The titanium content in the solid content at this time was 2.41% 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.

[Brief description of drawings]

FIG. 1 is a flow chart for explaining the present invention.

Claims (3)

[Claims] 1. A) (a) aluminum stearate,
(B) dialkoxymagnesium, (c) diester of aromatic dicarboxylic acid, (d) halogenated hydrocarbon and (e) general formula TiX ₄ (wherein X is a halogen element).
A catalyst component obtained by contacting the titanium halide represented by the above formula with the composition obtained by contacting the titanium halide twice more, (B) general formula SiRm (OR ′) ₄ -m ( In the formula, R is hydrogen, an alkyl group or an aryl group, R ′ is an alkyl group or an aryl group, and m is 0 ≦ m ≦ 4.) And a (C) organoaluminum compound. A catalyst for olefin polymerization, which is characterized in that 2. The catalyst component (A) after grinding the components (a) and (b), the resulting composition is treated with the components (c) and (e) in the presence of the component (d). The catalyst for olefin polymerization according to claim (1), which is obtained by contacting. 3. The catalyst component (A) comprises components (a) and (b).
The catalyst for olefin polymerization according to claim (1), which is obtained by crushing (c) and (c) and then contacting the resulting composition with component (e) in the presence of component (d).