JPH0665686B2 - Olefin polymerization catalyst - Google Patents

Description

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

[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 polymer yield 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 contact residue was unavoidable. Since this deashing process uses a large amount of alcohol or a chelating agent, a recovery device or a regenerating device for them is indispensable, and there are many resources, energy, and other incidental problems, and a person skilled in the art would like to immediately solve the problem. It was an important issue. In order to omit this complicated deashing process, many studies have been made and proposed to increase the polymerization activity per titanium in the contact component, especially the 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 it is 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 inventors of the present invention have disclosed that, in order to reduce the 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, Japanese Patent Application No. 57-91.
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) fatty acid calcium, (b) dialkoxymagnesium (c) diester of aromatic dicarboxylic acid,
(D) halogenated hydrocarbon, and (e) general formula TiX
_{4 The} composition obtained by contacting with a titanium halide represented by the formula (X is a halogen element) (hereinafter, may be simply referred to as titanium halide) is further repeated twice, and the titanium halogen is repeated. (B) a general formula SiRm (OR ') _4- m (wherein R is hydrogen, an alkyl group or an aryl group, R'is an alkyl group or an aryl group, The present invention is to provide a catalyst for olefin polymerization, which comprises a silicon compound represented by m ≦ 0 ≦ m ≦ 4 (hereinafter, may be simply referred to as a silicon compound); and (C) an organoaluminum compound.

As the fatty acid calcium used in the present invention,
Saturated fatty acid calcium is preferred.

As dialkoxy magnesium used in the present invention, diethoxy magnesium, dibutoxy magnesium, diphenoxy magnesium, dipropoxy magnesium, di-sec-butoxy magnesium, di-tert-
Examples thereof include butoxy magnesium, diisopropoxy magnesium and the like, among which diethoxy magnesium and dipropoxy magnesium are preferable.

The fatty acid calcium and dialkoxymagnesium are preferably used in a form in which water is removed as much as possible.

The diester of aromatic dicarboxylic acid used in the present invention is preferably a diester of phthalic acid or terephthalic acid, for example, dimethyl phthalate, dimethyl terephthalate, diethyl phthalate, diethyl terephthalate, dipropyl phthalate, dipropyl terephthalate, dibutyl phthalate, dibutyl. Examples thereof include terephthalate, diisobutylphthalate, diamylphthalate, diisoamylphthalate, ethylbutylphthalate, ethylisobutylphthalate and ethylpropylphthalate.

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 bromide, propyl iodide, o-dichlorobenzene and benzyl. Examples thereof include chloride, dichloroethane, trichloroethylene, dichloropropane, dichlorobenzene, trichloroethane, carbon tetrachloride, chloroform and methylene chloride, and among them, o-dichlorobenzene, propyl chloride, dichloroethane, chloroform, carbon tetrachloride, And methylene chloride are preferred.

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

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. , Tetramethoxysilane, tetraethoxysilane, trimethoxyethylsilane, trimethoxymethylsilane, triethoxymethylsilane, ethyltrietokinsilane, ethyltriisopropoxysilane, and the like.

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, but usually fatty acids are used. 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 in the range of 0.1 g or more, preferably 1 g or more based on 1 g of the total of calcium and dialkoxymagnesium. Further, the halogenated hydrocarbon is used in an arbitrary ratio, but is preferably an amount capable of forming a suspension.

In this case, the order of contact of the respective raw materials forming the catalyst component is, as the first embodiment, after crushing the fatty acid calcium and dialkoxymagnesium, and then diester of aromatic dicarboxylic acid and titanium halogen in the presence of halogenated hydrocarbon. The composition obtained by contacting the compound with
Repeatedly contacting the titanium halide, or as a second embodiment, after crushing fatty acid calcium, dialkoxymagnesium and diester of aromatic dicarboxylic acid, contacting with titanium halide in the presence of halogenated hydrocarbon. The composition obtained by adding 2
It is preferable to repeatedly contact the titanium halide.

The grinding of the fatty acid calcium 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 is brought into contact with the diester of aromatic dicarboxylic acid and the titanium halide. Is usually 0 in the presence of halogenated hydrocarbons.
It is carried out for 5 minutes to 100 hours in the temperature range from ℃ to the boiling point of the titanium halide used.

The pulverization of fatty acid calcium, dialkoxymagnesium and 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, and the obtained composition is contacted with titanium halide. Is carried out in the presence of halogenated hydrocarbon in the temperature range from 0 ° C. to the boiling point of the titanium halide used, for 5 minutes to 100 hours.

It is also possible to wash the catalyst component with an organic solvent such as n-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 is used in combination with the above silicon compound and organoaluminum compound to form a catalyst for olefin polymerization. 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 a 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.

The olefins homopolymerized or copolymerized using the catalyst 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, as a result, it has a very high activity, so that the catalyst residue in the produced polymer is 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.

As can be seen from the fact that the fatty acid calcium is generally used as a stabilizer of the polymer in the present invention, even if it remains in the polymer obtained by using the catalyst component of the present invention, it does not adversely affect the polymer. Not only is it not possible to give it, but it is expected that it will contribute to the stability of the polymer.

Further, the 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 the production of industrial olefin polymers, it is generally said that hydrogen coexists at the time of polymerization 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 coexistence of hydrogen using the catalyst obtained by the present invention, the activity and stereoregularity are hardly reduced even when the MI of the produced polymer is extremely high. Such an effect brings extremely great benefits to those skilled in the art.

〔Example〕

 Specific examples will be described below.

Example 1 [Preparation of catalyst component] 5 g of calcium stearate and 45 g of diethoxymagnesium were charged into a vibrating mill pot of 1.0 volume filled with 4/5 of a total volume of 25 mmφ stainless balls under a nitrogen gas atmosphere, and the vibration frequency was set. 1 at 1430 v.pm and a swing of 3.5 mm
Grinding treatment was carried out 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, 2.0 ml of dibutyl phthalate and 200 ml of TiCl ₄ were added with stirring, and the temperature was raised to 110 ° C. and the reaction was carried out for 2 hours with stirring. . After completion of the reaction, it was washed 10 times with 200 ml of n-heptane at 40 ° C, and 40 ml of new TiCl ₄ was used.
After washing once at ℃, add 200 ml of TiCl ₄ to 110 ℃
And reacted for 2 hours with stirring.

After the reaction was completed, it was cooled to 40 ° C, and then 200 ml of n-heptane
The washing was repeated, and when chlorine was not detected in the washing liquid, the washing was completed and the catalyst component was used. At this time, the solid content of the catalyst component was separated and the titanium content of the solid content was measured to be 3.81% by weight.

〔polymerization〕

700 ml of n-heptane was charged into an autoclave with an internal volume of 2.0, which was completely replaced with nitrogen gas, and 301 mg of triethylaluminum was added while maintaining a nitrogen gas atmosphere.
64 mg of phenyltriethoxysilane and then 0.3 mg of the above catalyst component as titanium atoms were charged. Then hydrogen gas 120
While charging ml and raising the temperature to 70 ° C and introducing propylene gas
Polymerization was carried out for 4 hours while maintaining a pressure of 6 kg / 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). Further, the obtained solid polymer is extracted with boiling n-heptane for 6 hours 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 1.5 g of dipropyl phthalate was used. The titanium content in the solid content at this time was 4.13% by weight. An experiment was conducted in the same manner as in Example 1 except that 70 mg of phenyltriethoxysilane was used for 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 3.69% 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 5 g of calcium stearate and 45 of diethoxy magnesium
g and 15 g of dibropyr phthalate were ground as in Example 1. 6 g of the obtained composition was sufficiently replaced with nitrogen gas and placed in a round bottom flask having a capacity of 500 ml equipped with a stirrer, charged with 15 ml of o-dichlorobenzene and 200 ml of TiCl ₄ and heated to 110 ° C. And reacted for 2 hours with stirring.
After completion of the reaction, it was washed 10 times with 200 ml of 40 ° C. n-heptane, and once again with 200 ml of TiCl ₄ at 40 ° C.
200 ml of TiCl ₄ was added, and the mixture was stirred and reacted at 90 ° C. for 2 hours. After completion of the reaction, the reaction mixture was cooled to 40 ° C. and further washed with 200 ml of n-heptane repeatedly. When chlorine was no longer detected in the washing liquid, the washing was ended to obtain a catalyst component. The titanium content in the solid content at this time was 3.88% 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) fatty acid calcium, (b) dialkoxymagnesium, (c) diester of aromatic dicarboxylic acid, (d) halogenated hydrocarbon, and (e).
A contact component prepared by contacting the titanium halide represented by the general formula TiX ₄ (wherein X is a halogen element) with the composition obtained by contacting the titanium halide twice more. (B) General formula SiRm (OR ′) _4- m (wherein 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). ) A silicon compound represented by the formula; and (C) an organoaluminum compound, which is a catalyst for olefin polymerization. 2. A catalyst component (A) is obtained by crushing components (a) and (b) and then in the presence of component (d), component (c).
And the composition obtained by contacting with (e) further 2
The catalyst for olefin polymerization according to claim 1, which is prepared by repeatedly contacting the component (e) repeatedly. 3. A composition obtained by crushing components (a), (b) and (c) and then contacting catalyst component (A) with component (e) in the presence of component (d). And (2) are prepared by contacting the component (e) by repeating the above procedure twice more.
The olefins polymerization catalyst described.