JPH0723404B2 - Olefin polymerization catalyst - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention provides a stereoregular polymer having a highly active activity and an ordered particle size distribution in an extremely high yield when subjected to the polymerization of olefins. A highly active catalyst that can be obtained, more specifically, a solid composition obtained by contacting dialkoxy magnesium, a diester of an aromatic dicarboxylic acid, a halogenated hydrocarbon, and a titanium halide is further contacted with water. The present invention relates to an olefin polymerization catalyst comprising an olefin polymerization catalyst component, a silicon compound and an organoaluminum compound obtained.

[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. The so-called deashing process for removing the catalyst residue was unavoidable because the polymer yield per titanium (hereinafter referred to as the catalyst component and the polymerization activity per titanium in the catalyst component) was low. 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 trend, when a transition metal compound such as titanium halide which is an active ingredient is supported on a carrier substance such as magnesium chloride and 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 the drawback that it adversely affects the polymer produced as well as the halogen element in titanium halides, and 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 0454, a method for producing a catalyst component for polymerization of olefins was proposed, and the intended purpose was achieved. Further, when the polymerization of olefins, particularly the stereoregular polymerization of propylene, 1-butene and the like is industrially carried out, it is usually necessary to make an electron donating compound such as an aromatic carboxylic acid ester coexist in the polymerization system. It is indispensable in a catalyst that uses a catalyst component having a carrier of (1) as a carrier in combination with an organoaluminum compound. However, this aromatic carboxylic acid ester imparts an ester odor peculiar to the produced polymer, and its removal is a major problem in the art.

Further, in a so-called highly active supported catalyst, such as a catalyst using a catalyst component having magnesium chloride as a carrier,
Although the activity at the initial stage of the polymerization is high, the deactivation is large, which causes a problem in the process operation, and when it is necessary to prolong the polymerization time such as block copolymerization, it is practically impossible to use. In order to improve this point, 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-O-R are prepared.
A method of using it for the polymerization of olefins in combination with a compound having a group has been shown, but since the organic carboxylic acid ester is used during the polymerization, the problem of the odor of the produced polymer has not been solved, and As can be seen from the above, very complicated operations are required, and it cannot be said that a practically sufficient one is obtained in terms of performance and sustainability of activity.

Further, the so-called highly active supported catalyst component using magnesium chloride as a carrier has a drawback that its performance deteriorates as the storage period becomes longer. This can be said to be a very serious problem in consideration of the fact that when the catalyst component is industrially used, it usually takes several months for storage and transportation.

Further, although it is necessary to supply the catalyst to a high temperature polymerization tank in an industrial polymerization apparatus, it is known that the performance of the conventional supported catalyst is considerably lowered in such a case. . This is sometimes a big problem in the so-called continuous polymerization method, and its improvement has been a strong demand in the field.

Further, the particle size distribution of the produced polymer is also a very important issue industrially in plant operation, but different processes are required for each process, and it is difficult for conventional supported catalysts to handle this in detail. It was

The inventors of the present invention have reached the present invention as a result of earnest research in order to solve the problems remaining in such conventional techniques, and make a proactive proposal.

[Means for solving problems]

That is, the features of the present invention are: (A) (a) dialkoxymagnesium, (b) diester of aromatic dicarboxylic acid, (c) halogenated hydrocarbon, and (d) general formula TiX ₄ (wherein X is a halogen element.) A composition obtained by contacting a titanium halide represented by the formula (hereinafter, may be simply referred to as titanium halide) with (e) water, and then again with the titanium. A catalyst component obtained by contacting a halide, (B) the 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 a silicon compound represented by 0 ≦ m ≦ 4 (hereinafter, may be simply referred to as a silicon compound); and (C) an olefin polymerization catalyst comprising an organoaluminum compound. Located in.

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 and diisopropoxy magnesium, and among them, diethoxy magnesium and dipropoxy magnesium are preferable.

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, for example, propyl chloride, butyl chloride, butyl bromide, propyl iodide, chlorobenzene, benzyl chloride, dichloroethane. , Trichloroethylene, dichloropropane, dichlorobenzene, trichloroethane, carbon tetrachloride, chloroform, methylene chloride and the like, among which 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. Examples of the alkylalkoxysilane include tetramethoxysilane, tetraethoxysilane, trimethoxyethylsilane, trimethoxymethylsilane, triethoxymethylsilane, ethyltriethoxysilane, and ethyltriisopropoxysilane.

When obtaining the solid composition of the present invention, the use ratio of each raw material and the contact conditions are optional, and are not particularly limited, as long as they do not adversely affect the performance of the produced catalyst component. With respect to 1 g of dialkoxy magnesium, 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
The range is 0.1 g or more, preferably 1 g or more. Further, the halogenated hydrocarbon is used in an arbitrary ratio, but is preferably an amount capable of forming a suspension.

Further, the contact of each raw material is usually carried out at a temperature from 0 ° C. to the boiling point of the titanium halide used for 100 hours or less, preferably 10 hours or less.

At this time, the order and method of contacting each raw material are not particularly limited, and any appropriate one can be selected.

The contact between the fixing composition obtained as described above and water is usually 100 g or less, preferably 50 g or less, and 100 hours or less, using 1 g or less of water, relative to 1 g of the solid composition, preferably Less than 10 hours.

The water used here is preferably used in the form of being contained in an aliphatic or aromatic hydrocarbon or halogenated hydrocarbon.

After the contact, the titanium halide is again contacted with the obtained solid composition, but it may be washed with an organic solvent such as n-heptane before or after the contact.

The catalyst component produced as described above is combined with the silicon compound and the organoaluminum compound to form a catalyst for olefin polymerization. The organoaluminum compound used is 1 in mole ratio per mole of titanium atom in the catalyst component.
Used in the range of up to 1000, and the silicon compound has a molar ratio of 1 or less per mol of the organoaluminum compound, preferably 1 or less.
Used in the range of 0.005-0.5.

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 / c
m ² · G or less, preferably 50 kg / cm ² · G or less.

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

〔Example〕

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

Example 1 << Preparation of catalyst components >> Capacity of 200 m, which was sufficiently replaced with real gas and equipped with a stirrer
A 1-liter round-bottomed flask was charged with 5 g of diethoxymagnesium, 1.5 g of dibutylphthalate and 25 ml of methylene chloride to give a suspension, and the mixture was stirred under reflux for 1 hour. Then, this suspension was pumped into 200 ml of room temperature TiCl ₄ in a 500 ml round bottom flask equipped with a stirrer, heated to 110 ° C. and reacted for 2 hours while stirring. After completion of the reaction, n-heptane 20 at 40 ℃
The solid composition was obtained by washing 10 times with 0 ml. Then the solid composition 3
Into a round-bottomed flask having an internal volume of 500 ml, 100 ml of n-heptane containing 10 ppm of water was added, treated at room temperature for 1 hour with stirring, and then washed with 200 ml of n-heptane at room temperature 5 times to newly prepare TiCl ₄ 200 ml was added and reacted at 120 ° C. 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 obtained. In addition,
At this time, the titanium content in the catalyst component was measured 3.
It was 01% by weight.

<< Overlap >> 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.
32 mg of phenyltriethoxysilane and then 0.3 mg of the above catalyst component as titanium atoms were charged. Then hydrogen gas 300
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. As a result of measuring the particle size distribution of the produced polymer, 100 μ or less was 3% by weight.

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. The result of particle size distribution measurement of the produced polymer was 100 μm.
The following was 2% by weight.

Example 3 A catalyst component was prepared in the same manner as in Example 1 except that 200 ml of n-heptane containing 10 ppm of water was used. In addition,
At this time, the titanium content in the solid content was 3.11% 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. As a result of measuring the particle size distribution of the produced polymer, 100 μm or less was 2% by weight.

Example 4 An experiment was conducted in the same manner as in Example 1 except that the treatment with n-heptane containing water was conducted at 50 ° C. The titanium content in the solid content at this time was 3.04% 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. As a result of measuring the particle size distribution of the produced polymer, 100 μm or less was 2% by weight.

[Effects of the Invention] When olefins are polymerized using the catalyst obtained according to the present invention, the catalyst residue in the produced polymer can be suppressed to an extremely low level because the catalyst has a very high activity. Moreover, since the amount of residual chlorine is very small, the effect of chlorine on the produced polymer can be reduced to the extent that no deashing step is required.

Chlorine contained in the produced polymer causes corrosion of equipment used in processes such as granulation and molding, and also causes deterioration of the produced polymer itself, yellowing, etc. Has a very important meaning to those skilled in the art.

Further, the feature of the present invention is that not only the big problem of the odor of the produced polymer is solved by not using the aromatic carboxylic acid ester during the polymerization, but the activity per unit time of the catalyst is It is an object of the present invention to solve the essential drawback of so-called highly active supported catalysts, which is significantly reduced with the increase of the above, and to provide a catalyst that can be practically applied not only to homopolymerization but also to copolymerization.

Conventionally, in the industrial production of olefin polymers, it has been generally said that hydrogen is allowed to coexist at the time of polymerization from the viewpoint of MI control and the like, but a catalyst using the above-mentioned catalyst component having magnesium chloride as a carrier coexists with hydrogen. Below, it had the disadvantage that activity and stereoregularity were significantly reduced. However, when olefins are polymerized in the presence of hydrogen using the catalyst obtained according to the present invention, the MI of the produced polymer is
The activity and stereoregularity are hardly deteriorated even when the value is extremely high, and such an effect brings an extremely great benefit to those skilled in the art.

Further, the catalyst component or the catalyst produced according to the present invention has a more ordered particle size distribution, and can exert an industrially extremely beneficial effect that the particle size distribution can be controlled.

[Brief description of drawings]

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

Claims (1)

[Claims] 1. (A) (a) dialkoxy magnesium,
A solid obtained by contacting (b) a diester of an aromatic dicarboxylic acid, (c) a halogenated hydrocarbon and (d) a titanium halide represented by the general formula TiX ₄ (where X is a halogen element). A catalyst component obtained by (e) contacting the composition with water and then contacting the titanium halide again, (B) General formula SiRm (OR ') 4-m (wherein R is hydrogen or an alkyl group). Or an aryl group, R ′ is an alkyl group or an aryl group, and m is 0 ≦ m ≦ 4, and (C) an organoaluminum compound, which is characterized in that Polymerization catalyst.