JPH0458483B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing polyolefin, and more particularly to a method for producing high-quality polyolefin using a catalyst that has high olefin polymerization activity despite the use of a small amount of a titanium compound. Conventionally, a combination of a titanium catalyst component containing a magnesium compound such as magnesium chloride and an organoaluminum compound has been known as a catalyst with high olefin polymerization activity, and it is possible to polymerize olefin using such a catalyst. It is widely practiced. However, in the conventional method described above, the amount of titanium compounds such as titanium tetrachloride used in the preparation of the catalyst is larger than that of magnesium compounds. There was a problem in that the disposal of surplus titanium compounds discharged after the polymerization reaction was expensive. In addition, the conventional method uses a large amount of highly halogenated titanium such as titanium tetrachloride, resulting in a high halogen content in the resulting polyolefin, resulting in problems such as deterioration of product quality and corrosion of molding equipment. It was hot. The present inventors have conducted extensive research in order to solve the problems of the above-mentioned conventional techniques and to develop a method for producing high-quality polyolefin using a small amount of titanium compound and using a highly active catalyst. As a result, as a titanium-containing component, which is a component of the catalyst,
Reaction product obtained by reacting aromatic carboxylate of magnesium with a small amount of titanium compound ()
The inventors have discovered that by using this method, a high-quality polyolefin can be efficiently produced and the intended purpose can be achieved, and the present invention has been completed. That is, the present invention provides for producing a polyolefin by polymerizing an olefin using a catalyst containing (A) a titanium-containing component and (B) an organoaluminum compound as a main component. For carboxylate salts, the general formula TiX _n (OR) _4-
n [In the formula, R represents an alkyl group, a cycloalkyl group, or an aryl group having 1 to 10 carbon atoms, and X represents a halogen atom. Moreover, m is a real number of 0 or more and 4 or less. ] 0.05 to 0.4
The present invention provides a method for producing a polyolefin, which is characterized by using a reaction product () obtained by adding and reacting at a ratio of (molar ratio). As mentioned above, the titanium compound used in the present invention is represented by the general formula TiX _n (OR) _4-n ,
Here, R represents an alkyl group, cycloalkyl group, or aryl group having 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms, and X represents a halogen atom such as a chlorine atom, a bromine atom, or an iodine atom. Also, m is usually 0, 1, 2,
It is an integer of 3 or 4, but it does not necessarily have to be an integer, but may be a real number between 0 and 4, for example, 0 as the average value of a mixture of various titanium compounds.
It is sufficient if ≦m≦4. Specific examples of this titanium compound include titanium tetrahalides such as TiCl ₄ , TiBr ₄ , TiI ₄ , Ti(OCH ₃ )Cl ₃ Ti(OC ₂ H ₅ )
_Cl3 ,Ti(O_・n- _C4H9 ) _Cl3 ,Ti _{( OC2H5} ) _Br3
trihalogenated monoalkoxytitanium, such as
Ti( _OCH3 ) _2Cl2 ,Ti _{( OC2H5} ) _{2Cl2 ,} Ti(O・_n-
Dihalogenated dialkoxytitanium such as C ₄ H ₉ ) ₂ Cl ₂ , Ti(OC ₂ H ₅ ) ₂ Br ₂ , Ti(OCH ₃ C) ₃ Cl, Ti
(OC ₂ H ₅ ) ₃ Cl, Hi (O・n-C ₄ H ₉ ) ₃ Cl, Ti
Monohalogenated trialkoxytitanium such as (OC ₂ H ₅ ) ₃ Br, as well as Ti(OCH ₃ ) ₄ , Ti(OC ₂ H ₅ ) ₄ ,
Tetraalkoxy titanium such as Ti(OC ₃ C ₃ H ₇ ) ₄ and Ti(O·n-C ₄ H ₉ ) ₄ can be mentioned. In the present invention, these may be used alone or in combination. On the other hand, there are various aromatic carboxylates of magnesium to be reacted with the titanium compound, and various kinds can be used. Specific examples of aromatic carboxylates constituting this aromatic carboxylate include benzoic acid, and alkyl-substituted benzoic acids such as toluic acid, ethylbenzoic acid, isopropylbenzoic acid, dimethylbenzoic acid, and trimethylbenzoic acid; Halogen-substituted benzoic acids such as fluorobenzoic acid, chlorobenzoic acid, bromobenzoic acid, iodobenzoic acid, dichlorobenzoic acid, dibromobenzoic acid, alkoxy or acyloxybenzoic acids such as anisic acid, phenoxybenzoic acid, acetoxybenzoic acid, phthalic acid , aromatic dicarboxylic acids such as chlorophthalic acid and dichlorophthalic acid, polycyclic aromatic carboxylic acids such as naphthalenecarboxylic acid and anthracenecarboxylic acid, and carboxylic acid salts containing aromatic rings such as phenylacetic acid. In the present invention, since such an aromatic carboxylate is used, the amount of titanium compound to be reacted with it is small, and a cleaning step with a titanium compound and a solvent is not required in the catalyst preparation stage. becomes. Here, when reacting the titanium compound represented by the general formula TiX _n (OR) _4-n with the aromatic carboxylate of magnesium, the amount of titanium compound is 0.05% per mole of the aromatic carboxylate. Add at a rate of ~0.4 mole. If the amount of titanium compound used is too large, the catalytic activity decreases, making it necessary to wash the excess titanium compound with a solvent and also processing the waste titanium compound, making it impossible to achieve the object of the present invention. Moreover, even if the titanium compound is used in an amount exceeding the above-mentioned ratio, it hardly contributes to improving the activity of the resulting catalyst. This reaction is usually carried out in an inert hydrocarbon solvent such as pentane, hexane, or heptane at a temperature of 0 to 200°C.
Preferably 30 to 150°C, reaction time 5 minutes to 10 hours,
Preferably, the heating time is 30 minutes to 5 hours. Furthermore, in the reaction between the titanium compound and the aromatic carboxylate described above, an electron-donating compound can be added to participate in the reaction, if desired. The electron-donating compounds used here are usually organic compounds containing oxygen, nitrogen, phosphorus or sulfur. Specifically, amines, amides, ketones, nitriles, phosphines, phosphoramides, esters, thioethers, thioesters, acid anhydrides, acid halides, aldehydes,
Examples include organic acids. More specifically, organic acids such as aromatic carboxylic acids such as benzoic acid and p-oxybenzoic acid; acid anhydrides such as succinic anhydride, benzoic anhydride, and p-toluic anhydride; acetone, methyl ethyl ketone, Ketones with 3 to 15 carbon atoms such as methyl isobutyl ketone, acetonephenone, benzophenone, and benzoquinone; aldehydes with 2 to 15 carbon atoms such as acetaldehyde, propionaldehyde, octylaldehyde, benzaldehyde, tolualdehyde, and naphthaldehyde; formic acid Methyl, methyl acetate, ethyl acetate, vinyl acetate, propyl acetate, octyl acetate, cyclohexyl acetate, ethyl propionate, methyl butyrate, ethyl valerate, methyl chloroacetate, ethyl dichloroacetate, methyl methacrylate, ethyl crotonate, ethyl pivalate , dimethyl maleate, ethyl cyclohexanecarboxylate, methyl benzoate, ethyl benzoate,
Propyl benzoate, butyl benzoate, octyl benzoate, cyclohexyl benzoate, phenyl benzoate, benzyl benzoate, methyl toluate, ethyl toluate, amyl toluate, ethyl ethylbenzoate, methyl anisate, ethyl anisate,
Esters with 2 to 18 carbon atoms such as ethyl ethoxybenzoate, ethyl p-butoxybenzoate, ethyl o-chlorobenzoate, ethyl naphthoate, γ-butyrolactone, δ-valerolactone, coumarin, phthalide, and ethylene carbonate; acetyl Acid halides having 2 to 15 carbon atoms such as chloride, benzyl chloride, toluyl chloride, anisyl chloride; methyl ether, ethyl ether, isopropyl ether, n-butyl ether, amyl ether,
Ethers with 2 to 20 carbon atoms such as tetrahydrofuran, anisole, diphenyl ether, and ethylene glycol butyl ether; Acid amides such as acetic acid amide, benzoic acid amide, and toluic acid amide; Tributylamine, N,N'-dimethylpiperazine, and Examples include amines such as livenzylamine, aniline, pyridine, picoline, and tetramethylethylenediamine; nitrites such as acetonitrile, benzonitrile, and tolnitrile; tetramethylurea, nitrobenzene, and lithium butyrate. Among these, esters, ethers, ketones, acid anhydrides and the like are preferred. Particularly preferred are alkyl esters of aromatic carboxylic acids, such as alkyl esters of aromatic carboxylic acids having 1 to 4 carbon atoms, such as benzoic acid, p-methoxybenzoic acid, p-ethoxybenzoic acid, and toluic acid; Also preferred are aromatic ketones, aromatic carboxylic acid anhydrides such as benzoic anhydride, and ethers such as ethylene glycol butyl ether. The amount of this electron-donating compound to be used is not particularly limited and may be determined as appropriate depending on various circumstances, but it is usually 0.01 to 0.5 mol, preferably 0.02 mol, per 1 mol of the above-mentioned aromatic carboxylate. ~0.2 mol. In the present invention, the reaction product (
The reaction product (2) is used as component (A) (titanium-containing component) of an olefin polymerization catalyst. According to the method of the present invention, two components (A) and (B) are prepared, in which the above reaction product () is used as the component (A) (titanium-containing component), and the organoaluminum compound is used as the component (B). Polyolefin is produced by polymerizing olefin using a catalyst as the main component. In the polymerization of olefin, the reaction product () as component (A) and the organoaluminum compound as component (B) are added to the reaction system, and then the olefin as a raw material is introduced into the system. The polymerization method and conditions are not particularly limited, and any of solution polymerization, suspension polymerization, gas phase polymerization, etc. is possible, and both continuous polymerization and discontinuous polymerization are possible. Taking the case of solution polymerization or suspension polymerization as an example, the amount of the catalyst component added is 0.001 to 5.0 mmol/, preferably 0.002 to 1 mmol/in terms of titanium atoms of component (A), and (B) The amount of the component is 1 to 5,000 (molar ratio), preferably 5 to 1,000 (molar ratio) to the titanium atoms in component (A). The olefin pressure in the reaction system is preferably normal pressure to 50 kg/cm ² and the reaction temperature is 0 to 300°C, preferably 50 to 250°C. Molecular weight adjustment during polymerization can be carried out by known means, such as hydrogen. The reaction time may be appropriately selected from 5 minutes to 10 hours, preferably from 30 minutes to 5 hours. There are various organoaluminum compounds that are component (B) of the catalyst used in the method of the present invention. Alkylaluminum compounds, and diethylaluminium monochloride, diisopropylaluminum monochloride,
Dialkyl aluminum monohalides such as diisobutyl aluminum monochloride and dioctyl aluminum monochloride are preferred, and mixtures thereof are also preferred. There are various types of olefins that can be polymerized by the method of the present invention, including linear monoolefins such as ethylene, propylene, butene-1, hexene-1, and octene-1, as well as 4-methyl-pentene-1 and the like. branched monoolefins, dienes such as butadiene, and others, and the present invention
It can be effectively used for homopolymerization of these or copolymerization of various α-olefins. According to the method of the present invention, the amount of titanium compounds consumed during the preparation of the catalyst used is small, and almost all of the titanium compounds used are used as catalysts, so there is no need for equipment for processing waste titanium compounds. . Furthermore, since the catalytic activity is extremely high, a deashing step (catalyst removal step) is not necessary, and as a result, polyolefin can be produced extremely efficiently. Furthermore, this polyolefin has a low halogen content and is of very high quality, and there is no fear of corroding the extruder used for molding this polyolefin. Next, the present invention will be explained in more detail with reference to Examples. Example 1 (1) Preparation of titanium-containing component In a 200 ml flask purged with argon, 50 ml of dehydrated n-heptane, 2.67 g (10 mmol) of magnesium benzoate anhydride, and 0.19 titanium tetrachloride were placed.
g (1 mmol) and reacted for 3 hours under refluxing n-heptane to obtain the entire amount of the reactant as a titanium-containing component (reaction product ()). (2) Polymerization of olefins In an argon-substituted autoclave with an internal volume of 1, 400 ml of dehydrated n-hexane, 2 mmol of triethylaluminum, 2 mmol of diethylaluminum chloride, and 0.02 mmol of the titanium-containing component obtained in (1) above are added as titanium atoms. and heat to 80℃
The temperature was raised to 1, and hydrogen was supplied so that the hydrogen partial pressure was 3 Kg/cm ² . Next, ethylene was continuously supplied so that the partial pressure of ethylene was 5 kg/cm ² and the polymerization reaction was carried out for 1 hour to obtain 157 g of polyethylene. The results are shown in Table 1. Comparative Example 1 (1) Preparation of titanium-containing component The amount of titanium tetrachloride used in Example 1 (1) was
A titanium-containing component (reaction product (2)) was obtained in the same manner as in Example 1 (1) except that the amount was 0.95 g (5 mmol). (2) Polymerization of olefin The above titanium-containing component in Example 1 (2)
89 g of polyethylene was obtained in the same manner as in Example 1 (2) except that the titanium-containing component obtained in (1) was used.
The results are shown in Table 1. Comparative Example 2 (1) Preparation of titanium-containing component The amount of titanium tetrachloride used in Example 1 (1) was
A titanium-containing component (reaction product (2)) was obtained in the same manner as in Example 1 (1) except that the amount was 9.49 g (50 mmol). (2) Polymerization of olefin The above titanium-containing component in Example 1 (2)
8 g of polyethylene was obtained in the same manner as in Example 1 (2) except that the titanium-containing component obtained in (1) was used. The results are shown in Table 1. Comparative Example 3 (1) Preparation of titanium-containing component The titanium-containing component (reaction product ()) obtained in Example 2 (1) was washed with n-heptane by decantation until no chloride ions were detected. A titanium-containing component was obtained repeatedly. The amount of titanium supported on this product was 160 mg.Ti/g.carrier. (2) Polymerization of olefin The above titanium-containing component in Example 1 (2)
54 g of polyethylene was obtained in the same manner as in Example 1 (2) except that the titanium-containing component obtained in (1) was used. The results are shown in Table 1. Example 2 (1) Preparation of titanium-containing component 50 ml of dehydrated n-heptane and p-chlorobenzoic acid were placed in a 200 ml flask purged with argon.
3.13 g (20 mmol) was added thereto, and 30 ml of a heptane solution of ethylbutylmagnesium (10 mmol) was added dropwise at room temperature over 20 minutes. After the completion of dropping, the temperature was raised and n-
The reaction was carried out for 3 hours under heptane reflux. The temperature was lowered to 40°C, 0.19 g (1 mmol) of titanium tetrachloride was added, and the temperature was raised again to react for 3 hours under refluxing n-heptane. ) was obtained. (2) Polymerization of olefin The above titanium-containing component in Example 1 (2)
The titanium-containing component obtained in (1) is used as a titanium atom.
25 g of polyethylene was obtained in the same manner as in Example 1 (2) except that 0.005 mmol, 1 mmol of triethylaluminum chloride, and 1 mmol of diethylaluminum chloride were used. The results are shown in Table 1. Example 3 (1) Preparation of titanium-containing component In Example 2 (1), 3.13 g (20 mmol) of m-chlorobenzoic acid was used instead of p-chlorobenzoic acid.
A titanium-containing component (reaction product ()) was obtained in the same manner as in Example 3 (1) except that . (2) Polymerization of olefin The above titanium-containing component in Example 1 (2)
130 g of polyethylene was obtained in the same manner as in Example 1 (2) except that the titanium-containing component obtained in (1) was used. The results are shown in Table 1. Example 4 (1) Preparation of titanium-containing component Example 2 except that 3.82 g (20 mmol) of 3,5-dichlorobenzoic acid was used instead of p-chlorobenzoic acid in Example 2 (1). A titanium-containing component (reaction product ()) was obtained in the same manner as in (1). (2) Polymerization of olefin The above titanium-containing component in Example 1 (2)
The titanium-containing component obtained in (1) is used as a titanium atom.
40 g of polyethylene was obtained in the same manner as in Example 1 (2) except that 0.005 mmol, 1 mmol of triethylaluminum, and 1 mmol of diethylaluminium chloride were used. The results are shown in Table 1. Example 5 (1) Preparation of titanium-containing component Example 3 (1) except that 2.7 g (20 mmol) of p-toluic acid was used instead of p-chlorobenzoic acid in Example 2 (1). ) A titanium-containing component (reaction product ()) was obtained. (2) Polymerization of olefin The above titanium-containing component in Example 1 (2)
The titanium-containing component obtained in (1) is used as a titanium atom.
78 g of polyethylene was obtained in the same manner as in Example 1(2), except that 0.004 mmol, 1 mmol of triethylaluminum chloride, and 1 mmol of diethylaluminum chloride were used. The results are shown in Table 1. Example 6 (1) Preparation of titanium-containing component Titanium was prepared in the same manner as in Example 1 (1) except that 0.23 g (1 mmol) of tetraethoxytitanium was used instead of titanium tetrachloride in Example 1 (1). The contained components (reaction product ()) were obtained. (2) Polymerization of olefin The above titanium-containing component in Example 1 (2)
120 g of polyethylene was prepared in the same manner as in Example 1 (2) except that the titanium-containing component obtained in (1) was used.
I got it. The results are shown in Table 1. Example 7 (1) Preparation of titanium-containing components In a 200 ml flask purged with argon, 50 ml of dehydrated n-heptane, 2.67 g (10 mmol) of anhydrous magnesium benzoate, and n-butyl benzoate were added.
0.08 g (0.5 mmol) and titanium tetrachloride 0.19 g
(1 mmol) was added and reacted for 3 hours under refluxing n-heptane to obtain a titanium-containing component (reaction product ()). (2) Polymerization of olefin In Example 1 (2), polyethylene 56
I got g. The results are shown in Table 1.

【table】

【table】 [Brief explanation of drawings]

FIG. 1 is a drawing showing the steps for preparing a catalyst used in the method of the present invention.

Claims (1)

[Claims] 1. In producing a polyolefin by polymerizing an olefin using a catalyst containing (A) a titanium-containing component and (B) an organoaluminum compound as a main component, (A)
As a titanium-containing component, for an aromatic carboxylate of magnesium, the general formula TiX _n (OR) _4-n [wherein R represents an alkyl group, cycloalkyl group, or aryl group having 1 to 10 carbon atoms, X represents a halogen atom. Moreover, m is a real number of 0 or more and 4 or less. ] A method for producing a polyolefin, characterized in that a reaction product () obtained by adding and reacting a titanium compound represented by the following in a ratio of 0.05 to 0.4 (molar ratio) is used. 2 The aromatic carboxylate of magnesium has the general formula TiX _n (OR) _4-n [wherein R, X, and m are the same as above. ] The method according to claim 1, wherein an electron-donating compound is added and reacted with the titanium compound represented by the formula to obtain a reaction product ( ).