JPS6354723B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to the former catalyst component (hereinafter referred to as _{C3 or} more
- Abbreviated as olefin polymerization catalyst component. ). That is, the present invention relates to a method for producing a high-performance catalyst component that exhibits high activity when subjected to the polymerization of C ₃ or higher α-olefins and can yield a stereoregular polymer in high yield. More specifically, an electron-donating substance is further added to a composition obtained by co-pulverizing magnesium halide and aluminum triisopropoxide, and the resulting solid composition is co-pulverized with titanium halide. The present invention relates to a method for producing a catalyst component for polymerizing _C3 or higher α-olefins, which comprises contacting in a liquid phase or gas phase and then washing with an inert organic solvent. Conventionally, solid titanium halides have been well known and widely used as catalyst components for the polymerization of α-olefins with C3 _or higher. Because of the low polymerization activity (polymerization activity of
Since this deashing process uses a large amount of alcohol or chelating agent, it requires recovery equipment, etc., and there are many resource, energy, and other related problems, making it a major problem that those skilled in the art would like to solve as soon as possible. It was a challenge. 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, especially in the catalyst component. In particular, a recent trend is to support transition metal compounds such as titanium halides, which are active ingredients, on a porous carrier material, and to increase the specific surface area of the active ingredient to polymerize α-olefins with C3 _or higher. In recent years, many proposals have been made to dramatically increase the polymerization activity per titanium in the catalyst component. Furthermore, various proposals have been made regarding the effects of improving the carrier material itself, devising a supporting method, and adding a third component. For example, in Japanese Patent Publication No. 47-41676, a crushed and activated magnesium or zinc halide is suspended in a liquid phase of titanium tetrachloride,
Titanium is supported on titanium and then washed with an organic solvent, or the halide is contacted with an organic solvent in advance, the solvent is removed by evaporation, and then the titanium is suspended in a liquid phase of titanium tetrachloride. A method is disclosed in which the solid composition is supported, washed with an organic solvent, separated into solid and liquid, and the resulting solid composition is used as a catalyst component in the polymerization of olefins. This method has a great effect on the polymerization activity per titanium in the catalyst component, considering the state of the art at the time, but the yield of stereoregular polymer (total crystallinity The disadvantage was that the yield (expressed as a polymer yield) was extremely low. In order to eliminate such drawbacks, the
-126590, magnesium halide is brought into contact with a third component, an electron-donating substance, specifically an aromatic carboxylic acid ester, by mechanical means, and the resulting solid composition is injected with tetrahalogen. A method for obtaining a catalyst component by contacting titanium oxide in a liquid or gas phase is disclosed. According to this method, the polymerization activity per titanium is increased to such an extent that there is almost no practical difference even if the deashing step is omitted.
The yield of stereoregular polymers is still unsatisfactory and has not yet reached the level where it can be put to practical use industrially. Furthermore, as an improvement on the above method, Japanese Patent Application Laid-Open No. 52-87489 discloses a metal compound selected from aluminum, tin, and germanium containing at least an organic group or a halogen.
A method has been proposed in which seeds and magnesium halide are brought into contact with each other by pulverization in the presence of an organic acid ester, and compared to the former method, it has achieved certain effects in terms of polymerization activity per titanium and the yield of stereoregular polymers. However, when considering polymerization characteristics such as the yield of polymer per catalyst component (hereinafter referred to as polymerization activity per catalyst component) and the yield of stereoregular polymer, it becomes clear that this industry is becoming more sophisticated. It was not in a state that would satisfy the requirements, and there was still room for improvement. All of the above-mentioned catalyst components tend to place too much emphasis on improving the polymerization activity per titanium in the catalyst component, and therefore the yield of stereoregular polymers is sacrificed, albeit slightly. . In addition, the polymerization activity per catalyst component has not been given much importance, and this has been a cause of adverse effects other than titanium residue on the produced polymer. The present inventors have made a proposal based on their extensive research in order to solve the problems remaining in the prior art. That is, the feature of the present invention is that (a) the general formula
A composition obtained by co-pulverizing a magnesium halide represented by MgX ₂ (wherein X is a halogen element) and (b) aluminum triisopropoxide is further added with (c) an electron-donating substance. The solid composition obtained by (d) general formula TiX ₄ (in the formula
is a halogen element. ) in the liquid or gas phase, and then washed with an inert organic solvent until the presence of halogen elements is no longer recognized in the washing solution, after which the solid and liquid are separated and dried. Alternatively, it can be made into a slurry by adding an appropriate amount of an inert organic solvent and used as it is as a catalyst component for polymerizing α-olefins having C3 _or more. According to the present invention, an electron-donating substance is further added to a composition that has been processed and modified by co-pulverizing magnesium halide and aluminum triisopropoxide, and the resulting solid composition is used. By treating the titanium halide mentioned above, it is possible not only to increase the supporting ratio of titanium, which is an active component, and to increase the polymerization activity per titanium in the catalyst component, but also to highly increase the polymerization activity per catalyst component. It is possible to achieve an excellent effect on the yield of the stereoregular polymer while maintaining the same. Conventionally, titanium has been the most avoided among catalyst residues that have an adverse effect on the produced polymer. Therefore, efforts have been made to eliminate the catalyst residue removal step, that is, the deashing step, by increasing the polymerization activity per titanium, and have achieved some success. There is no doubt about the idea itself, but other substances contained in the catalyst component, such as the components of the carrier material in the case of a catalyst component with a carrier, may also have an undesirable effect on the produced polymer and the polymerization equipment. This was also known to those skilled in the art. The present invention has been made with this point in mind, and as a result, the polymerization properties, particularly the polymerization activity per catalyst component and the yield of stereoregular polymer, are generally improved. In this way, it has become possible to produce a high-performance catalyst component that not only eliminates the deashing step but also has an extremely excellent yield of stereoregular polymer. The magnesium halide represented by the general formula MgX ₂ (wherein X is a halogen element) used in the present invention is anhydrous MgCl ₂ , MgBr ₂ ,
Among them, MgCl ₂ is preferable, such as MgI ₂ . The electron-donating substance used in the present invention is selected from organic compounds containing at least one atom selected from oxygen, nitrogen, sulfur, and phosphorus atoms in the molecule, such as ether, ester, ketone, Examples include amines, phosphines, phosphinamides, and the like. More specifically, aliphatic ethers such as diethyl ether, aromatic ethers such as anisole, aliphatic carboxylic acid esters such as ethyl acetate and methyl methacrylate, ethyl benzoate, methyl toluate, ethyl toluate, and anis. Examples include aromatic carboxylic acid esters such as ethyl acid and diethyl phthalate, ketones such as acetone, phosphines such as triphenylphosphine, and phosphinamides such as hexaphosphineamide. Particularly preferred are aromatic carboxylic acid esters. The general formula TiX ₄ used in the present invention (in the formula
is a halogen element. Examples of the titanium halide represented by ) include TiCl ₄ , TiBr ₄ , TiI ₄ and the like, with TiCl ₄ being particularly preferred. Furthermore, it is not prohibited to use this titanium halide in the form of a complex with the above-mentioned electron-donating substance. Inert organic solvents used in the present invention include saturated aliphatic and aromatic hydrocarbon compounds such as hexane, heptane, octane, cyclohexane, benzene, toluene, etc.
When using these inert organic solvents, it is desirable to use one that has been sufficiently dehydrated using molecular sieves or the like. 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 aluminum triisopropoxide is used per mole of magnesium halide. The amount is 0.001 to 1 mol, preferably 0.005 to 0.5 mol, and the electron donating substance is 0.01 mol.
-10 mol, preferably 0.05-1 mol. Co-pulverization of magnesium halide and aluminum triisopropoxide and co-pulverization of the resulting composition and electron-donating substance in the present invention are usually preferably carried out by mechanical treatment, and the powder is finely pulverized. Any of the mills used for this purpose, such as ball mills, vibration mills, tower mills, impact mills, etc., can be selected arbitrarily. It goes without saying that the pulverization time will vary depending on the performance of the pulverizer, but in the case of co-pulverization of magnesium halide and aluminum triisopropoxide, it is usually preferable to carry out the treatment within a range of 0.5 to 10 hours.
Furthermore, co-pulverization of the composition and the electron-donating substance is also performed by the same mechanical treatment as described above, and the treatment time is usually in the range of 5 to 100 hours. The contact temperature of each of these components is not particularly limited as long as the object to be treated can be pulverized, but it is usually preferably 80° C. or lower. The catalyst component of the present invention is obtained by contacting the thus obtained solid composition with a titanium halide in a liquid or gas phase to support titanium, and then washing with an inert organic solvent. The contact between the titanium halide and the treated product of the magnesium halide, that is, the solid composition, is usually carried out at a temperature in the range of 20 to 100°C using a container equipped with a cooling device and equipped with a stirrer. The contact treatment time is arbitrary as long as the titanium in the titanium halide is sufficiently supported on the solid composition, but it is usually carried out in a range of 0.5 to 10 hours. After the treatment, the resulting slurry composition is washed with an inert organic solvent. At this time, the cleaning is considered complete when no halogen element is detected in the cleaning solution, and the solid and liquid are separated and dried, or an appropriate amount of an inert organic solvent is added to form a slurry, and the cleaning is completed as it is. It is used as a catalyst component for the polymerization of _C3 or higher α-olefins in the present invention. These series of operations in the present invention are performed under conditions in which oxygen, moisture, etc. are excluded as much as possible, for example, in an atmosphere of an inert gas such as nitrogen or argon. The catalyst component produced as described above has the general formula AlRmX ₃ as a transition metal component of a Ziegler type catalyst.
-m (wherein R is hydrogen or an alkyl group having 1 to 10 carbon atoms, X is a halogen element, and m is an integer of 1 to ₃ ) in combination with an organoaluminum compound represented by form a catalyst for similar polymerization. The organoaluminum compound used is used in a weight ratio of 1 to 300, preferably 1 to 100, per titanium atom of the catalyst component. Furthermore, there is no hindrance to the addition and use of a third component such as aromatic carboxylic acid esters during the polymerization. The polymerization process can be carried out either in the presence of an inert organic solvent or in the presence of a liquid olefin monomer. 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. C ₃ or higher α-olefins which are monopolymerized or copolymerized using the catalyst component produced by the method of the present invention include propylene, 1-butene, 4-methyl-pentene-1, and the like. The present invention will be specifically explained below using Examples and Comparative Examples. Example 1 [Preparation of catalyst components] 25 g of commercially available anhydrous magnesium chloride and 1.0 g of aluminum triisopropoxide were placed in a vibrating mill pot with a capacity of 1 filled with 3/5 of the total volume of 15 mmφ stainless steel balls under a nitrogen atmosphere. The powder was ground for 1 hour at a vibration frequency of 1430 v.pm and a shaking width of 3.5 mm.
After grinding, add 7.8g of ethyl benzoate under nitrogen atmosphere.
was charged and further subjected to pulverization treatment for 17 hours under the same conditions. All of these pulverization treatments were performed at room temperature. TiCl ₄ 50 in a 200 ml round bottom flask with a cooling device, well purged with nitrogen gas and equipped with a stirrer.
ml and the solid composition obtained by the pulverization process.
10 g was charged, and a stirring reaction was carried out at 65° C. for 2 hours. After the reaction was completed, the mixture was cooled to room temperature, left to stand, and the supernatant liquid was removed by decantation. Next, washing with 100 ml of dehydrated n-heptane was carried out repeatedly, and when chlorine was no longer detected in the washing liquid, the washing was completed and used as a catalyst component. Furthermore, when the solid and liquid in the catalyst component were separated and the titanium content of the solid was measured, it was found to be 2.08% by weight. [Polymerization] Dehydrated n-heptane 500ml in an autoclave with an internal volume of 1.5 and equipped with a stirring device that was completely purged with nitrogen gas.
ml, and while maintaining a nitrogen gas atmosphere, 20 mg of triethylaluminum was charged, followed by 0.90 mg of the catalyst component as titanium atoms. Thereafter, the temperature was raised to 60°C, and propylene polymerization was carried out for 2 hours while maintaining a pressure of 4 kg/cm ² ·G while introducing propylene gas. After the completion of polymerization, the obtained solid polymer is filtered,
It was heated to 80°C and dried under reduced pressure. On the other hand, the liquid was concentrated to obtain a polymer soluble in the polymerization solvent. Let the amount of polymer dissolved in the polymerization solvent be (A), and the amount of solid polymer be (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 per catalyst component is expressed by the formula, [(A)+(B)](g)/amount of catalyst component (g), and the yield of crystalline polymer is expressed by the formula, (C)/(B)×100( %). Further, the yield (D) of the total crystalline polymer is determined by the formula: (D)=(C)/(A)+(B)×100(%). The results obtained are shown in Table 1. Example 2 The amount of aluminum triisopropoxide was 2.0
A catalyst component was prepared in the same manner as in Example 1, except that g was changed. Incidentally, the titanium content of the solid component at this time was 1.97% by weight. During the polymerization, 1.39 mg of the obtained catalyst component was charged as titanium atoms, and an experiment was conducted in the same manner as in Example 1. The results obtained are shown in Table 1. Example 3 A catalyst component was prepared in the same manner as in Example 1, except that the pulverization time after addition of ethyl benzoate was changed to 40 hours. In addition, the titanium content of the solid component at this time is
It was 2.09% by weight. During the polymerization, 1.35 mg of the obtained catalyst component was charged as titanium atoms, and an experiment was conducted in the same manner as in Example 1. The results obtained are shown in Table 1. Example 4 A catalyst component was prepared in the same manner as in Example 2, except that the pulverization time of anhydrous magnesium chloride and aluminum triisopropoxide was changed to 5 hours. In addition, the titanium content of the solid component at this time was 1.88
It was in weight%. During the polymerization, 1.05 mg of the obtained catalyst component was charged as titanium atoms, and an experiment was conducted in the same manner as in Example 1. The results obtained are shown in Table 1. Comparative Example 1 A catalyst component was prepared in the same manner as in Example 1 except that aluminum triisopropoxide was not added. Incidentally, the titanium content of the solid component at this time was 1.40% by weight. During the polymerization, 0.83 mg of the obtained catalyst component as titanium atoms was charged, and an experiment was conducted in the same manner as in Example 1. The results obtained are shown in Table 1. Comparative Example 2 A catalyst component was prepared in the same manner as in Example 1, except that MgCl ₂ , aluminum triisopropoxide, and ethyl benzoate were simultaneously added in the same quantitative ratio as in Example 1 and co-pulverized for 18 hours. . Incidentally, the titanium content of the solid component at this time was 1.72% by weight. During the polymerization, 1.26 mg of the obtained catalyst component was charged as titanium atoms, and an experiment was conducted in the same manner as in Example 1. The results obtained are shown in Table 1. Comparative Example 3 The ratio of each component was the same as in Example 1, except that MgCl ₂ and ethyl benzoate were pulverized for 1 hour in advance, and then aluminum triisopropoxide was added and pulverized for 17 hours. The catalyst components were uniquely tuned. Incidentally, the titanium content of the solid component at this time was 1.66% by weight. During the polymerization, 1.12 mg of the obtained catalyst component was charged as titanium atoms, and an experiment was conducted in the same manner as in Example 1. The results obtained are shown in Table 1. Comparative Example 4 A catalyst component was prepared in the same manner as in Example 1 except that aluminum ethoxide was used in place of aluminum triisopropoxide. Incidentally, the titanium content of the solid component at this time was 1.69% by weight. During the polymerization, 1.42 mg of the obtained catalyst component was charged as titanium atoms, and an experiment was conducted in the same manner as in Example 1. The results obtained are shown in Table 1.

[Table] As is clear from Table 1, magnesium halide, which is a carrier material, is modified by co-pulverization with aluminum triisopropoxide, and further pulverized with the addition of an electron-donating substance. When α-olefins are polymerized using the catalyst component obtained by the method of the present invention, in which the catalyst component is brought into contact with titanium tetrahalide and then washed with an inert organic solvent, the polymerization characteristics, especially the catalyst The polymerization activity per component and the yield of stereoregular polymer are improved in an extremely well-balanced manner. This is in recognition of the efforts that have been made to achieve the goal of eliminating the so-called deashing step by improving the polymerization activity per titanium unit in developing such supported catalyst components. This is also the result of research by the present inventors, who began to improve catalyst components from the viewpoint of comprehensively improving polymerization properties, particularly polymerization activity per catalyst component, and yield of stereoregular polymer. As mentioned above, the substances that adversely affect the produced polymer as so-called catalyst residues are not just titanium, but also other substances that form the catalyst component, specifically, if we take a catalyst component with a magnesium chloride support as an example, it is the carrier material. We focused on the fact that components such as chlorine and magnesium have a considerable negative effect on the polymer produced, and aimed to improve the polymerization activity per catalyst component, as well as improve the yield of stereoregular polymer. . To summarize the technical features of the present invention, magnesium halide and aluminum triisopropoxide as a carrier are co-pulverized and modified by mechanical means, and the resulting composition and an electron-donating substance are A novel method of co-pulverizing and contacting titanium halide, which is an active ingredient, by the same mechanical means as described above increases the loading rate of titanium on the carrier, resulting in the above-mentioned effects. It is expected that this product will provide a highly practical catalyst component for the polymerization of α-olefins.

[Brief explanation of drawings]

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

Claims (1)

[Claims] 1 (a) a magnesium halide represented by the general formula MgX ₂ (wherein X is a halogen element);
(b) A composition obtained by co-pulverizing aluminum triisopropoxide, further adding (c) an electron-donating substance and co-pulverizing the resulting solid composition with the general formula (d)
C ₃ or higher α-olefin, which is produced by contacting with a titanium halide represented by TiX ₄ (wherein X is a halogen element) in a liquid phase or gas phase, and then washing with an inert organic solvent. A method for producing a catalyst component for type polymerization.