JPH0421684B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a high-performance catalyst component that acts with high activity when subjected to the polymerization of olefins and can obtain a stereoregular polymer in high yield. More specifically, the present invention provides a method for producing a catalyst component suitable for producing a polymer having a high bulk density and a narrow particle size distribution, and specifically,
A solid composition obtained by contacting a magnesium compound or the magnesium compound with at least one selected from an electron donor and a halogen-containing compound (hereinafter sometimes simply referred to as "solid composition"), This invention relates to a method for producing a catalyst component for polymerizing olefins, which comprises carrying out a stirring treatment together with a liquid flocculant in a dispersant and then contacting it with a halogen-containing titanium compound in the presence or absence of an electron donor. be.

Conventionally, many proposals have been made regarding methods for producing solid catalyst components containing magnesium, titanium, halogen, and the like.

In most of these, transition metal compounds such as titanium halides are supported on magnesium halides, and when used in the polymerization of olefins, the polymerization activity per titanium in the catalyst component is dramatically increased. However, on the other hand, problems remain in that the shape of the particles of the produced polymer is not constant, the particle size distribution is wide, and the bulk density is not sufficiently high.

Proposals have also been made regarding methods to solve such problems. For example, Japanese Patent Application Laid-Open No. 49-65999 discloses a method for obtaining substantially uniform particles by spraying an aqueous solution of magnesium halide or molten magnesium halide (MgX ₂ .6H ₂ O). However, this method requires a special device called a spray granulator in order to spray at high pressure, and requires additional steps such as heating to melt it and drying when using an aqueous solution. Problems remain. Furthermore, JP-A-55-
No. 135102 discloses a method in which a suspension containing complex particles of magnesium halide and an active hydrogen compound in a molten state is dispersed in an organic liquid medium in the coexistence of a surfactant or a polysiloxane, and then rapidly cooled and solidified. There is. However, this method has the disadvantage that the process becomes complicated because it requires heating to a high temperature and immediately quenching in order to solidify uniformly.

As a result of intensive research to solve the problems remaining in the prior art, the present inventors have developed a catalyst component that is extremely easy to operate and can achieve the desired purpose without using special equipment. The purpose is to find a manufacturing method and propose it to the public.

That is, the present invention is characterized by subjecting the solid composition to a stirring treatment in a dispersant together with a liquid flocculant to obtain a stirring treatment product, and then stirring the solid composition in the presence or absence of an electron donor. The catalyst component is obtained by contacting with a halogen-containing titanium compound, and the process is simple and the operation is extremely simple.

When the catalyst component obtained by the present invention is used for the polymerization of olefins, the obtained polymer has the advantage of having a uniform particle shape, a narrow particle size distribution, and a high bulk density. . Of course, the polymerization properties of the catalyst components, particularly the polymerization activity and the yield of stereoregular polymer, are comparable to those of conventionally known ones.

To further comment on the features of the present invention, the solid composition and the liquid flocculant are made to coexist in a dispersing agent that does not dissolve the solid composition, and after a stirring treatment, the solid composition and the liquid flocculant are mixed together in the presence or absence of an electron donor. The catalyst component is produced using a novel method in which the catalyst component is brought into contact with a halogen-containing titanium compound.

Although the mechanism by which such a simple method achieves the above-mentioned effects is not clear, the particles of the solid composition are incorporated into droplets of the liquid flocculant dispersed in the dispersant, and the liquid The solid composition is flocculated by the action of the flocculant, and in addition, the particles in the droplets are tightly flocculated due to collisions between particles and interactions between the particles and the inner wall of the device due to the stirring operation, and the solid composition is further flocculated in the liquid flocculant. It is thought that the particles are gradually arranged as the action of incorporating the particles is repeated. Then, by contacting this product with a halogen-containing titanium compound in the presence or absence of an electron donor, a catalyst component for polymerizing olefins that can achieve the objects of the present invention can be produced.

The effects of the present invention have been described above, but a more detailed explanation will be given below.

(1) Olefin polymers obtained using the catalyst components obtained in the present invention exhibit high bulk density. Therefore, especially in the case of slurry polymerization, the burden of drying the produced polymer is reduced, and it is also possible to increase the slurry concentration, thereby increasing the production amount per unit.

(2) The resulting polymer has a narrow particle size distribution and a well-defined particle shape. Furthermore, since the amount of fine powder is reduced, the danger of dust explosions can be avoided.

(3) The resulting polymer has good fluidity, making handling such as transportation and storage easier.

(4) It is also possible to control the particle size of the catalyst component by selecting the conditions during the stirring treatment.

As a result, it is possible to produce an olefin polymer in which the pelletizing step can be omitted depending on the type of polymer resin in the industrial olefin polymer production process.

Magnesium compounds used in the present invention include magnesium halides, alkoxymagnesium halides, allyloxymagnesium halides, dialkoxymagnesium, diallyloxymagnesium, fatty acid magnesium, inorganic magnesium, and more specifically magnesium chloride. , magnesium bromide, magnesium iodide, methoxymagnesium chloride, ethoxymagnesium chloride, isopropoxymagnesium chloride, butoxymagnesium chloride, methoxymagnesium bromide, ethoxymagnesium bromide, isopropoxymagnesium bromide, phenoxymagnesium chloride, methylphenoxymagnesium chloride, Phenoxymagnesium bromide, methylphenoxymagnesium bromide, diethoxymagnesium, diisopropoxymagnesium, dibutoxymagnesium, diphenoxymagnesium, magnesium stearate, magnesium octoate, magnesium laurate, magnesium caproate, magnesium oxalate, oxidized Magnesium, magnesium hydroxide, magnesium carbonate, magnesium sulfate, magnesium and aluminum double oxide, magnesium and silicon double oxide, and the like can be mentioned.
Furthermore, it is also possible to use two or more of these compounds.

The halogen-containing compounds used in the present invention include sulfur halides such as hydrogen chloride and thionyl chloride, or halides such as boron, aluminum, silicon, germanium, tin, lead, phosphorus, arsenic, antimony, bismuth, and zinc; Alternatively, a halogen-containing titanium compound represented by the general formula Ti(OR) _o x _4-o (wherein R is a hydrocarbon group, X is a halogen, and n is 0 or an integer from 1 to 3) can be mentioned.

The electron donor used in the present invention is an organic compound containing at least one atom selected from oxygen, nitrogen, sulfur, and phosphorus in its molecule, such as ether, ester, ketone,
Examples include phosphinamide. More specifically, aliphatic ethers such as diethyl ether, aromatic ethers such as anisole, ethyl acetate,
Examples include aliphatic carboxylic acid esters such as methyl methacrylate, aromatic carboxylic acid esters such as ethyl toluate, ethyl anisate, and ethyl benzoate, ketones such as acetone, and phosphine amides such as triphenylphosphine. Among them, aromatic carboxylic acid esters are preferred, and ethyl benzoate, ethyl p-anisate, and ethyl p-toluate are particularly preferred.

The halogen-containing titanium compound used in the present invention has the general formula Ti(OR) _o X _4-o (wherein R is a hydrocarbon group, X is a halogen, and n is 0 or an integer from 1 to 3). is a titanium compound shown,
Specifically, TiCl ₄ , TiBr ₄ , TiI ₄ , Ti(OCH ₃ )
_Cl3 , Ti( _OC2H5 ) _Cl3 , Ti( _O -n- _C4H9 ) _{Cl3 ,}
Ti(OC ₂ H ₅ ) Br ₃ , Ti(OCH ₃ ) ₂ Cl ₂ , Ti(OC ₂ H ₅ ) ₂
Cl ₂ ,Ti(OC ₂ H ₅ ) ₂ Br ₂ ,Ti(OCH ₃ ) ₃ Cl ,Ti(OC ₂
H ₅ ) ₃ Cl, Ti(OC ₂ H ₅ ) ₃ Br, etc., but among them
_TiCl4 is preferred.

The dispersant used in the present invention includes aliphatic hydrocarbons, aromatic hydrocarbons, alicyclic hydrocarbons, aliphatic halogenated hydrocarbons, aromatic halogenated hydrocarbons, which do not dissolve the solid composition, and alicyclic halogenated hydrocarbons. More specifically, they include hexane, heptane, benzene, toluene, xylene, methylcyclohexane, methylene chloride, 1,2-dichloroethane, benzene chloride, and the like.

The liquid flocculant used in the present invention includes oxygen-containing organic compounds such as alcohols and esters that have affinity with the solid composition, nitrogen-containing organic compounds such as amines and amides, phosphines, and phosphates. These are sulfur-containing organic compounds such as phosphorus-containing organic compounds, sulfides, and sulfoxides, and are organic compounds that have the property of being difficult to dissolve in dispersants. More specific examples include ethanol, 1-propanol, 1-butanol, benzyl alcohol, ethylene glycol, diethylene glycol, diethylamine, triethylamine, dipropylamine, ethanolamine, diethanolamine, NN-dimethylformamide, N,N'-dimethylacetamide, Examples include diethylphosphine, triethylphosphine, diphenylphosphine, triethyl phosphate, dimethyl sulfoxide, dimethyl sulfide, diethyl sulfide and the like. Further, it is not prohibited to use two or more of these liquid flocculants in combination.

As the stirring treatment method in the present invention, any method can be selected as long as each component used can be sufficiently stirred and the object of the present invention can be achieved.

Although the order of addition of each component in the present invention is not particularly limited, the following method may be cited as an example.

(1) A method in which the solid composition is suspended in a dispersant, and then a liquid flocculant is added and stirred.

(2) A method in which the solid composition is charged and stirred while a liquid flocculant is added to a dispersant and dispersed.

(3) A method in which a liquid flocculant and the solid composition are simultaneously added to a dispersant and then stirred.

etc. can be exemplified.

The proportions of the dispersant, liquid flocculant, and solid composition used when carrying out the stirring process in the present invention are arbitrary as long as the purpose of the present invention can be achieved.
It varies depending on the type of liquid flocculant and dispersant, the composition and ingredients of the solid composition, etc., but usually the liquid flocculant is added to 1 g of the solid composition containing magnesium.
0.001 to 10 ml, preferably 0.01 to 5 ml, the dispersant is 5 ml or more, preferably 10 ml per 1 ml of liquid flocculant.
It is used in the above range.

The treatment temperature in the present invention is lower than the boiling point of the dispersant and is within a temperature range at which the liquid flocculant does not crystallize or solidify in the dispersant, usually -10 to 50°C.
temperature range.

The stirring treatment time in the present invention is not particularly limited either, but is in the range of 1 minute to 10 hours, preferably 10 minutes to 5 hours.

The method of contacting the product obtained by the stirring treatment with the halogen-containing titanium compound in the present invention is not particularly limited. A method of contacting the halogen-containing titanium compound in the presence or absence at a temperature up to the boiling point of the halogen-containing titanium compound for 10 minutes to 100 hours is mentioned.

In addition, at this time, it is possible to coexist an inert hydrocarbon solvent during the treatment, or to repeat the contact with the halogen-containing titanium compound two or more times.

It is also possible to contact the stirred product with a halogen-containing titanium compound in the presence or absence of an electron donor and then wash it with an inert hydrocarbon solvent.

The catalyst component produced as described above is combined with an organoaluminum compound to form a catalyst for polymerizing olefins. The organoaluminum compound used is used in a molar ratio of 1 to 1000, preferably 1 to 300, per mole of titanium atoms in the catalyst component. Further, it is not prohibited to add and use a third component such as an electron-donating substance during the polymerization.

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. The polymerization temperature is 200°C or less, preferably 100°C or less, and the polymerization pressure is 100Kg/cm ² ·G or less, preferably 50Kg/cm ² ·G or less.

Olefins homopolymerized or copolymerized using the catalyst component produced by the method of the present invention include ethylene, propylene, 1-butene, 4-methyl-1
-Pentene etc.

The present invention will be specifically explained below using Examples and Comparative Examples.

The physical property values in the examples were measured by the following methods. The bulk density of the solid polymer was measured according to JIS K6721. The particle size distribution of the solid polymer is
Measurements were made using a rotary sieve shaker equipped with a JIS standard sieve. PSD value = log integrated particle size 84% particle size / integrated particle size 16%
It was determined by particle size. The closer this value is to 0, the narrower the particle size distribution is.

Example 1 (Preparation of a solid composition) 40 g of magnesium stearate, 8 ml of ethyl benzoate, and TiCl ₄ are placed in a 500 ml round bottom flask, well purged with nitrogen gas and equipped with a stirrer.
200 ml was charged and stirred at room temperature for 30 minutes. followed by 65
The temperature was raised to .degree. C. and maintained at that temperature for 2 hours. Separately, 400 ml of n-heptane was charged into a 1000 ml three-necked flask equipped with a stirrer under a nitrogen atmosphere. After the above-mentioned product was pumped into this, it was allowed to stand still, and the supernatant liquid was extracted by decantation. Next, washing was performed 10 times with 400 ml of n-heptane to obtain a solid composition.

(Preparation of catalyst components) After sufficient purging with nitrogen gas, use a stirrer and
400 ml of n-heptane and 9 g of the above solid composition were charged into a cylindrical flask (internal volume: 500 ml) with an inner diameter of 85 mm and equipped with a stirring blade of φ. Next, add 1.35 ml of ethanol while stirring and keep at room temperature.
The mixture was stirred for 1 hour at a stirring speed of 2000 rpm. Furthermore n-
The stirred product was obtained by washing three times with heptane.

8 g of the above stirring product and 100 ml of TiCl ₄
The mixture was placed in a 200 ml three-necked flask under a nitrogen atmosphere, heated to 65°C, and stirred at that temperature for 2 hours. After standing still, the supernatant liquid was removed by decantation and washed with n-heptane to obtain a catalyst component.

(Polymerization of propylene) 700 ml of n-heptane was charged into an autoclave equipped with a stirrer with an internal volume of 1.5 that was completely purged with nitrogen gas, and while maintaining a nitrogen gas atmosphere, 300 mg of triethylaluminum and 137 mg of ethyl p-toluate were added.
And 0.9 mg of the above catalyst component was charged as a titanium atom. After that, 100 ml of hydrogen was added, the temperature was raised to 60°C, and propylene gas was introduced. Polymerization was carried out for 2 hours while maintaining the propylene pressure at 6 kg/cm ² ·G. The amount of solid polymer was 227 g, and the n-heptane extraction residue was 95.5%. The polymerization activity per gram of Ti at this time was 251 Kg-pp/g-Ti.

Further, the bulk density of the solid polymer was 0.43 g/cc, and the PSD value was 0.48.

Comparative Example 1 40 g of magnesium stearate, 8 ml of ethyl benzoate and 200 ml of TiCl ₄ were placed in a 500 ml round bottom flask that was sufficiently purged with nitrogen gas and equipped with a stirrer.
ml and stirred at room temperature for 30 minutes. Subsequently, the temperature was raised to 65°C and maintained at that temperature for 2 hours. Separately, 400 ml of n-heptane was placed in a 1000 ml three-necked flask equipped with a stirrer under a nitrogen atmosphere. After the above product was pumped into this, it was allowed to stand, and the supernatant liquid was extracted by decantation. Then n-heptane
The catalyst component was obtained by washing 10 times with 400 ml.

Further, as a result of carrying out propylene polymerization in the same manner as in Example 1, the amount of solid polymer and the n-heptane extraction residue were 186 g and 95.1%, respectively.
At this time, the polymerization activity per gram of Ti is 220Kg−
pp/g-Ti. The bulk density of the solid polymer is
It was 0.33 g/cc, and the PSD value was 0.90.

Example 2 A catalyst component was prepared in the same manner as in Example 1 except that triethylamine was used instead of ethanol.

Further, propylene polymerization was carried out in the same manner as in Example 1. The resulting amount of solid polymer and n-
Heptane extraction residual rate is 200g and 94.8% respectively
It was hot. The polymerization activity per gram of Ti at this time was 225 Kg-pp/g-Ti.

Further, the bulk density of the solid polymer was 0.45 g/cc, and the PSD value was 0.38.

Example 3 (Preparation of solid composition) 5 g of magnesium stearate, 5 g of diethoxymagnesium, 2.5 ml of ethyl benzoate, and 1,2-dichloroethane are placed in a 200 ml round bottom flask that is sufficiently purged with nitrogen gas and equipped with a stirrer.
50 ml of the solution was added to form a suspension, and the mixture was stirred under reflux for 2 hours. Next, this suspension was pumped into 200 ml of TiCl ₄ at 0° C. in a 500 ml round bottom flask equipped with a stirrer, heated to 90° C., and reacted with stirring for 2 hours. After the reaction was completed, it was cooled to 40°C, and then n-
A solid composition was obtained by washing 10 times with 200 ml of heptane.

(Preparation of catalyst components) In a cylindrical flask having the same specifications as in Example 1, which was sufficiently purged with nitrogen gas and equipped with a stirrer, 400 ml of n-heptane and 1 ml of ethanol were placed and stirred. Then, 4.5 g of the above solid composition was added,
The mixture was stirred at room temperature for 1 hour at a stirring speed of 2000 rpm. The mixture was further washed with 200 ml of n-heptane to obtain a stirred product.

4 g of the above stirring treatment product and 200 ml of TiCl ₄
The mixture was placed in a 500 ml three-necked flask under a nitrogen atmosphere, heated to 90°C, and stirred for 2 hours. Then, it was cooled to 40°C and the supernatant liquid was removed. Further n
- Repeated washing with 200 ml of heptane;
When chlorine was no longer detected in the cleaning solution, cleaning was completed and a catalyst component was obtained.

(Polymerization of propylene) Propylene polymerization was carried out in the same manner as in Example 1, except that the polymerization temperature was changed to 70°C. As a result, the amount of solid polymer and the n-heptane extraction residue were 260 g and 96.4%, respectively. Ti1 at this time
The polymerization activity per gram was 300 Kg-pp/g-Ti.

Further, the bulk density of the solid polymer was 0.40 g/cc, and the PSD value was 0.56.

Comparative Example 2 The same operation as in Example 3 was performed except that the stirring treatment with ethanol was not performed.

Further, propylene polymerization was carried out in the same manner as in Example 1 except that the amount of the catalyst component was 0.5 mg in terms of titanium atoms. The resulting amount of solid polymer and yield of crystalline polymer are 170g each.
and 95.0%. The polymerization activity per gram of Ti at this time was 350 Kg-pp/g-Ti.

Further, the bulk density of the solid polymer was 0.32 g/cc, and the PSD value was 0.94.

Example 4 A catalyst component was prepared in the same manner as in Example 3 except that ethylene glycol was used instead of ethanol. Further, propylene polymerization was carried out in the same manner as in Example 1. As a result, the amount of solid polymer and n-heptane extraction residual rate are respectively
It was 237g and 95.5%. At this time, the polymerization activity per gram of Ti was 29.2 Kg-pp/g-Ti.

Further, the bulk density of the solid polymer was 0.43 g/cc, and the PSD value was 0.60.

[Brief explanation of drawings]

FIG. 1 is a flowchart showing a typical example of a process for preparing a catalyst component of the present invention.

Claims (1)

[Claims] 1. Magnesium stearate, dialkoxymagnesium, ethyl benzoate and an aliphatic halogenated hydrocarbon are brought into suspension and then mixed under reflux to form a suspension; Pour, add, and contact into titanium tetrachloride to form a solid composition, mix and suspend the solid composition with an aliphatic hydrocarbon, and then mix and stir with a liquid flocculant to form a stirred product. 1. A method for producing a catalyst component for polymerizing olefins, which comprises contacting the stirred product with titanium tetrachloride. 2. mixing magnesium stearate, ethyl benzoate and titanium tetrachloride and then contacting at elevated temperature; pumping, adding and contacting the resulting product into an aliphatic hydrocarbon to form a solid composition; The solid composition is mixed and stirred with a dispersion obtained by mixing and dispersing a liquid flocculant with an aliphatic hydrocarbon to form a stirred product, and the stirred product is brought into contact with titanium tetrachloride. A method for producing a catalyst component for polymerizing olefins.