JPH0361684B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a catalyst component that exhibits high activity when subjected to the polymerization of olefins and is capable of obtaining stereoregular polymers in high yield. , production of a catalyst component for polymerizing olefins, characterized by contacting basic magnesium carbonate and magnesium halide in the presence of an aromatic carboxylic acid ester, and contacting the obtained solid composition with a titanium halide. It is about the method. Conventionally, solid titanium halides have been well known and widely used as catalyst components for the polymerization of olefins. Since the polymerization activity per titanium is low, a so-called demineralization step to remove catalyst residues has been unavoidable. Since this deashing process uses a large amount of alcohol or chelating agent, a recovery device or a regeneration device for the same is indispensable, and there are many resource, energy, and other related problems that should be resolved immediately by those skilled in the art. This was an important issue that needed to be addressed. In order to eliminate this complicated deashing process, many studies have been made and proposals have been made to increase the polymerization activity per titanium in the catalyst component, particularly in the catalyst component. In particular, a recent trend is to support transition metal compounds such as titanium halides, which are active ingredients, on carrier materials such as magnesium chloride, and when olefins are polymerized, the polymerization activity per titanium in the catalyst component can be dramatically increased. I've seen many suggestions for increasing it. However, the chlorine contained in magnesium chloride, which is the main carrier material, has the disadvantage of having an adverse effect on the produced polymer, and therefore magnesium chloride is the only material that can effectively act as a carrier material. Attempts have also been made to use Furthermore, attempts have been made to use various diluents and the like in order to alleviate the adverse effects of magnesium chloride. However, the methods proposed so far do not sufficiently meet the demands of the technical field, which require not only increasing the polymerization activity per catalyst component but also maintaining a high yield of stereoregular polymers. No gains are suggested. For example, according to the method disclosed in JP-A-48-16986, sodium carbonate and calcium sulfate are added during the grinding process of magnesium chloride and an electron-donating substance. However, it cannot be said that the incorporation of such carriers shows sufficiently satisfactory values not only in polymerization activity but also in the yield of stereoregular polymers. The present inventors have arrived at the present invention as a result of intensive research in order to solve the problems remaining in the prior art, and hereby propose the present invention. That is, the present invention is characterized by a solid composition obtained by contacting (a) basic magnesium carbonate and (b) magnesium halide in the presence of (c) an aromatic carboxylic acid ester. , (d) general formula TiX ₄
(In the formula, X is a halogen element.) It is used as a catalyst component for the polymerization of olefins by contacting it with a titanium halide represented by the formula (X is a halogen element). According to the present invention, it has become possible to further suppress residual chlorine, which has been a problem with catalyst components with magnesium chloride supports, which have conventionally been the mainstream in this technical field. Of course, it has been demonstrated that the method has extremely excellent effects on the yield of stereoregular polymers without sacrificing the intended purpose of polymerization activity. When olefins are polymerized using the catalyst component obtained by the present invention, the amount of catalyst residue in the resulting polymer can be kept extremely low, and since the amount of residual chlorine is very small, The influence of chlorine on coalescence can be reduced. Furthermore, it shows extremely excellent effects in terms of the yield of stereoregular polymers. In addition, when producing such polymers industrially, it is possible to reduce the amount of polymerization solvent used per polymer by increasing the bulk specific gravity of the resulting polymer, or to increase the effective volume of the polymerization container to improve pelletization. Increasing the capacity of the process, increasing the throughput of polymer drying equipment, and even reducing the size of storage containers.
It can bring a number of benefits to the trader.
The bulk specific gravity of the polymer obtained by using the catalyst component of the present invention is considerably higher than that of the polymer obtained by using the catalyst component mixed with sodium carbonate, etc. . As the basic magnesium carbonate used in the present invention, commercially available products can be appropriately selected and used, but it is preferable to perform vacuum baking before use. Magnesium halides used in the present invention include magnesium fluoride, magnesium chloride, magnesium bromide, magnesium iodide, and the like, with magnesium chloride being preferred. Examples of aromatic carboxylic acid esters used in the present invention include ethyl toluate, ethyl anisate, and ethyl benzoate. The titanium halide represented by the general formula TiX ₄ (wherein X is a halogen element) used in the present invention includes TiCl ₄ , TiBr ₄ , TiI ₄ and the like, with TiCl ₄ being preferred. Further, it is not prohibited to use this titanium halide in the form of a complex with the electron donating substance. After contacting the solid composition produced in the present invention with the titanium halide, the effect of the present invention can be further enhanced by further washing with an organic solvent such as n-heptane. The ratio of each component to be used is arbitrary as long as it does not adversely affect the performance of the catalyst component produced, and is not particularly limited, but usually 0.01 g of magnesium halide is used for 1 g of basic magnesium carbonate. The above amount is preferably used in the range of 0.1 to 10 g. In addition, the aromatic carboxylic acid ester is contained in a solid composition obtained by contacting basic magnesium carbonate with magnesium halide.
It is used in a proportion of 50% by weight, preferably 5 to 30% by weight. In the present invention, the contact between basic magnesium carbonate, magnesium halide, and electron donating substance is usually carried out by mechanical means.
Generally, ball mills, vibration mills, tower mills, impact mills, etc. are used. In addition, before this contact step, it is also possible to pre-contact basic magnesium carbonate and magnesium halide, treat it with a halogen-containing substance such as silicon tetrachloride or thionyl chloride, or heat treat it under vacuum. be.
The contact time will of course vary depending on the performance of the equipment used, but is usually in the range of 1 to 500 hours. Further, the contact temperature is not particularly limited, and may be within a contactable range. The catalyst component of the present invention is obtained by contacting the solid composition thus obtained with a titanium halide and then washing with an organic solvent as necessary. The contact between the titanium halide and the solid composition can be carried out using various methods, but it is carried out, for example, in a container equipped with a stirrer, usually at a temperature ranging from room temperature to the boiling point of the titanium halide used. The contact time is arbitrary as long as the solid composition and the titanium halide can be brought into sufficient contact with each other, but the contact time is usually in the range of 10 minutes to 100 hours. The composition obtained after the above treatment is optionally treated with n-
Wash using an organic solvent such as heptane. At this time, the cleaning is considered to be completed when no halogen element is detected in the cleaning solution, and the solid and liquid are separated and dried, or an appropriate amount of organic solvent is added to form a slurry, and the method of the present invention is carried out as it is. Used as a catalyst component for olefin polymerization. These series of operations in the present invention are preferably carried out in the absence of chlorine, moisture, and the like. The catalyst component produced as described above is combined with an organoaluminum compound to form a catalyst component for polymerizing olefins. The organoaluminum compound used has a ratio of 1 per mole of titanium atoms in the catalyst component.
-1000, preferably 1-300.
Further, it is not prohibited to add a third component such as an aromatic carboxylic acid ester during the polymerization. Polymerization can be carried out in the presence or absence of organic solvents. Further, the olefin monomer can be used in either a 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 that can be homopolymerized or copolymerized using the catalyst component produced according to the present invention include ethylene, propylene, 1-tene, 4-methyl-1-pentene, and the like. The present invention will be specifically explained below using Examples and Comparative Examples. Example 1 [Preparation of catalyst components] 12.5 g of commercially available basic magnesium carbonate vacuum calcined at 250°C for 7 hours, magnesium chloride
12.5g of ethyl benzoate and 5ml of ethyl benzoate were placed in a 25mmφ stainless steel ball in a nitrogen gas atmosphere.
5.Pour into a vibrating mill pot with a capacity of 1.0,
Grinding was carried out at room temperature for 17 hours at a frequency of 1430 v.pm and a width of 3.5 mm. 50 ml of TiCl ₄ and 10 g of the solid composition obtained by the above pulverization treatment were charged into a 200 ml round bottom flask that was sufficiently purged with nitrogen gas and equipped with a stirrer.
The reaction was stirred at ℃ for 2 hours. 50 after the reaction
The mixture was cooled to ℃, allowed to stand, and the supernatant liquid was removed by decantation. Next, washing with 100 ml of n-heptane was carried out repeatedly, and when chlorine was no longer detected in the washing liquid, the washing was deemed to have been completed and the catalyst component was used. At this time, when the solid and liquid in the catalyst component was separated and the titanium content in the solid component was measured, it was found to be 3.99% by weight. [Polymerization] Add 500 ml of n-heptane to an autoclave with a stirring device and an internal volume of 1.5 that was completely purged with nitrogen gas.
341 mg of triethylaluminum and 140 mg of ethyl p-toluate were charged while maintaining a nitrogen gas atmosphere.
And 2.84 mg of the above catalyst component was charged as titanium atoms. Thereafter, the temperature was raised to 60°C, and polymerization was carried out for 2 hours while maintaining a pressure of 4 kg/cm ² ·G while introducing propylene gas. After completion of polymerization, separate the obtained solid polymer and heat at 80℃.
and dried under reduced pressure. On the other hand, the amount of polymer dissolved in the polymerization solvent after concentrating the liquid is defined as (A), and the amount of solid polymer is defined as (B). Further, the obtained solid polymer was extracted with boiling n-heptane for 6 hours to obtain a polymer insoluble in n-heptane, and this amount was designated as (C). The polymerization activity (D) per catalyst component is expressed by the formula (D)={(A)+(B)}(g)/Amount of catalyst component (g). The polymerization activity (E) per chlorine contained in the catalyst component is calculated using the formula (E) = {(A) + (B)} (g) / amount of chlorine in the catalyst component (g
). In addition, the yield (F) of the crystalline polymer is expressed by the formula (F)=(C)/(B)×100(%), and the yield (G) of the total crystalline polymer is expressed by the formula (G)= Calculated from (C)/(A)+(B)×100(%). The obtained results indicate the bulk specific gravity of the produced polymer.
(H) as shown in Table 1. Example 2 [Preparation of catalyst components] 12.5 g of commercially available basic magnesium carbonate vacuum-calcined at 250°C for 7 hours, magnesium chloride
12.5 g was placed in a vibrating mill pot with a capacity of 1.0 filled with 4/5 of the total volume with 25 mmφ stainless steel balls under a nitrogen gas atmosphere, and the vibration frequency was 1430 vp.m and the amplitude was 3.5.
mm, and the grinding process was carried out at room temperature for 17 hours. The solid composition obtained by this pulverization treatment was transferred to an outer bottom flask with an internal volume of 300 ml under a nitrogen gas atmosphere,
Vacuum firing was performed at 250°C for 5 hours. then charging the solid composition into the vibratory mill;
5 ml of ethyl benzoate was added and pulverization was carried out for 17 hours. Solid composition 10 thus obtained
An experiment was conducted in the same manner as in Example 1 using g. In addition, the titanium content in the solid content at this time is
It was 3.20% by weight. [Polymerization] Triethylaluminum 164mg, p-ethyl toluate 67mg and catalyst component as titanium atom
The experiment was conducted in the same manner as in Example 1 except that 13.7 mg was charged. The results obtained are shown in Table 1. Example 3 [Preparation of catalyst components] 12.5 g of commercially available basic magnesium carbonate vacuum calcined at 250°C for 7 hours, magnesium chloride
12.5g was placed in a vibrating mill pot with a capacity of 1.0 filled with 4/5 of the total volume with 25mmφ stainless steel balls under a nitrogen gas atmosphere, the frequency was 1430v.pm, and the amplitude was 3.5.
mm, and the grinding process was carried out at room temperature for 17 hours. The solid composition obtained by this pulverization treatment was transferred to a round bottom flask with an internal volume of 300 ml under a nitrogen gas atmosphere, 100 ml of silicon tetrachloride was added, and a reaction was carried out under reflux for 2 hours. After completion of the reaction, the solid matter was taken out and dried under reduced pressure at room temperature, then placed in the vibrating mill pot, 5 ml of ethyl benzoate was added, and pulverization was carried out for 17 hours. An experiment was conducted in the same manner as in Example 1 using 10 g of the solid composition thus obtained. Note that the titanium content in the solid content at this time was 3.64% by weight. [Polymerization] Triethylaluminum 164mg, p-ethyl toluate 67mg and catalyst component as titanium atom
The experiment was conducted in the same manner as in Example 1 except that 1.37 mg was charged. The results obtained are shown in Table 1. Example 4 [Preparation of catalyst component] The same procedure as in Example 1 was carried out except that 8.2 g of commercially available basic magnesium carbonate vacuum-calcined at 250°C for 7 hours, 16.8 g of basic magnesium carbonate, and 6.0 ml of ethyl benzoate were used. I conducted an experiment. In this case, the titanium content in the solid content was 2.39% by weight.
It was hot. [Polymerization] An experiment was conducted in the same manner as in Example 1, except that 204.8 mg of triethylaluminum, 84 mg of ethyl p-toluate, and 1.72 mg of the catalyst component as titanium atoms were charged. The results obtained are shown in Table 1. Example 5 [Preparation of catalyst component] An experiment was conducted in the same manner as in Example 1 except that the pulverization step was carried out while maintaining the temperature at 0°C. Note that the titanium content in the solid content at this time was 2.70% by weight. [Polymerization] An experiment was conducted in the same manner as in Example 1, except that 204.8 mg of triethylaluminum, 84 mg of ethyl p-toluate, and 1.72 mg of the catalyst component as titanium atoms were charged. The results obtained are shown in Table 1. Example 6 [Preparation of catalyst component] An experiment was carried out in the same manner as in Example 1 except that the pulverization step was carried out while maintaining the temperature at 0° C. and the amount of ethyl benzoate was 4 ml. Note that the titanium content in the solid content at this time was 254% by weight. [Polymerization] An experiment was conducted in the same manner as in Example 1, except that 204.8 mg of triethylaluminum, 84 mg of ethyl p-toluate, and 1.72 mg of the catalyst component as titanium atoms were charged. The results obtained are shown in Table 1. Comparative Example 1 [Preparation of Catalyst Component] An experiment was conducted in the same manner as in Example 1, except that 12.5 g of commercially available sodium carbonate calcined in vacuum at 250° C. for 7 hours was used. Note that the titanium content in the solid content at this time was 6.38% by weight. [Polymerization] An experiment was conducted in the same manner as in Example 1, except that 327.6 mg of triethylaluminum, 105 mg of ethyl p-toluate, and 6.86 mg of the catalyst component as titanium atoms were charged. The results obtained are shown in Table 1. 【table】

[Brief explanation of drawings]

FIG. 1 is a flow chart showing the catalyst preparation process of the present invention.

Claims (1)

[Claims] 1. A solid composition obtained by contacting (a) basic magnesium carbonate and (b) magnesium halide in the presence of (c) aromatic carboxylic acid ester, (d)
1. A method for producing a catalyst component for polymerizing olefins, which comprises bringing it into contact with a titanium halide represented by the general formula TiX ₄ (wherein X is a halogen element).