JPH0567643B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for producing a polyolefin, and more particularly to a method for producing a high-quality polyolefin using a catalyst that has high olefin polymerization activity despite the use of a small amount of a titanium compound. [Prior art and problems to be solved by the invention] 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. Polymerization of olefins using such catalysts 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, conventional methods use large amounts 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. [Means for Solving the Problems] The present inventors have solved the problems of the prior art described above, and have developed a method for producing high-quality polyolefin using a small amount of titanium compound and a highly active catalyst. We conducted extensive research to develop it. As a result, as a titanium-containing component, which is a component of the catalyst,
By using the reaction product () obtained by reacting magnesium fatty acid salt with a small amount of titanium compound, or the reaction product () obtained by further reacting this with an organoaluminum compound, high-quality polyolefin can be efficiently produced. The present inventors have discovered that it is possible to produce the same and achieve the intended purpose, leading to the completion of the present invention. That is, the present invention provides (A) a titanium-containing component and (B) a titanium-containing component;
In producing polyolefin by polymerizing olefin using a catalyst containing an organoaluminum compound as a main component, (A) the general formula TiX _n (OR) _4- is used as a titanium-containing component for magnesium fatty acid salt.
_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 greater than or equal to 0 and less than 4. ] using a reaction product () obtained by adding and reacting a titanium compound represented by 0.5 or less (molar ratio), or further using this reaction product () with the general formula R′ _o AlX′ _{3 -o} [in the formula,
R' represents an alkyl group, cycloalkyl group or aryl group having 1 to 10 carbon atoms, and X' represents a halogen atom. Further, n represents a real number of 3 or less. The present invention provides a method for producing a polyolefin, which is characterized by using a reaction product ( ) obtained by reacting with an organoaluminum compound represented by the following. 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,
It is an integer of 1, 2, 3, or 4, but it does not necessarily have to be an integer, but may be a real number of 0 or more and less than 4, for example, 0≦m≦4 as the average value of a mixture of various titanium compounds. . Specific examples of this titanium compound include Ti(OCH ₃ )Cl ₃ and Ti(OC _2
H5 ) _Cl3 ,Ti ₍ O-n- _C4H9 ) _Cl3 ,Ti( _{OC2H5 )}
Trihalogenated monoalkoxytitanium such as _Br3 , _Ti ( _OCH3 ) _2Cl2 , Ti( _{OC2H5 ) 2Cl2 ,} Ti(O-
n- _C4H9 ) _{2Cl2 , dihalogenated} dialkoxytitanium such _as Ti( _OC2H5 ) _{2Br2 ,} Ti( _OCH3 ) _3Cl , Ti
( _OC2H5 ) _3Cl ,Ti( _{O-n-C4H9)3Cl , Ti ( OC2}
Monohalogenated trialkoxytitanium such as H ₅ ) ₃ Br, as well as Ti(OCH ₃ ) ₄ , Ti(OC ₂ H ₅ ) ₄ , Ti
Tetraalkoxytitaniums such as (OC 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 types of magnesium fatty acid salts to be reacted with the titanium compound, and various types can be used. Specific examples of fatty acids constituting this fatty acid salt include monocarboxylic acids such as acetic acid, propionic acid, palmitic acid, and stearic acid; dicarboxylic acids such as succinic acid and adipic acid; ketocarboxylic acids such as pyruvic acid and levulinic acid; Examples include unsaturated carboxylic acids such as linoleic acid and linolenic acid. Since such fatty acid salts are used in the present invention,
Only a small amount of the titanium compound to be reacted with the catalyst is required, and a cleaning step using the titanium compound and a solvent in the catalyst preparation stage is not required, resulting in high activity. Here, when reacting the titanium compound represented by the general formula TiX _n (OR) _4-n with the fatty acid salt of magnesium, the amount of the titanium compound is 0.5 mol or less, preferably 0.005 mol or less, per 1 mol of the fatty acid salt. ~0.4
Add in molar proportions. 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. Note that this reaction is usually performed in an inert hydrocarbon solvent such as pentane, hexane, or heptane at a temperature of 0 to 200°C.
C, preferably 30 to 150 C, and reaction time 5 minutes to 10 hours, preferably 30 minutes to 5 hours. Furthermore, in the reaction between the titanium compound and the fatty acid salt described above, an aromatic acid ester can be added to participate in the reaction if desired. Aromatic acid esters used here include 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, ethyl ethoxybenzoate, p-
Ethyl butoxybenzoate, ethyl o-chlorobenzoate, ethyl naphthoate, γ-butyrolactone,
Examples include δ-valerolactone, coumarin, and phthalide. Among these, 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, are preferred. The amount of aromatic acid ester to be used is not particularly limited and may be determined as appropriate depending on various circumstances, but it is usually 0.01 to 1 mol per mole of the fatty acid salt mentioned above.
The amount is 0.5 mol, preferably 0.02 to 0.2 mol. In the present invention, the aforementioned titanium compound and fatty acid salt,
Further, if necessary, an aromatic acid ester is added and reacted to obtain a reaction product (), and this reaction product () is used as component (A) (titanium-containing component) of an olefin polymerization catalyst. In addition, in the present invention, the reaction product () obtained by further reacting the above reaction product () with an organoaluminum compound is used as an olefin polymerization catalyst.
It is also effective to use it as component (A). The organoaluminum compound used here has the general formula R′ _o
It is represented by AlX' _3-o , where R' is an alkyl group, cycloalkyl group, or aryl group having 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms, and X' is a halogen atom. Further, n is a positive real number of 3 or less, specifically n=1, 1.5, 2, or 3. Specific examples of this organoaluminum compound include trialkylaluminum compounds such as trimethylaluminum triethylaluminum, triisopropylaluminium, triisobutylaluminum, trioctylaluminum, diethylaluminum monochloride, diethylaluminum monobromide, diethylaluminium monoiodide, diisopropyl Dialkyl aluminum monohalides such as aluminum monochloride, diisobutyl aluminum monochloride, dioctyl aluminum monochloride, or alkyl aluminum sesquihalides such as methyl aluminum sesquichloride, ethyl aluminum sesquichloride, ethyl aluminum sesquibromide, butyl aluminum sesquichloride are suitable; Mixtures of these are also suitable. When reacting the reaction product (2) with the above organoaluminum compound, the organoaluminum compound is usually added in a molar ratio of 0.1 to 100, preferably 0.1 to 100 (molar ratio) to the titanium atoms in the reaction product (2). 1-20
(molar ratio) of pentane,
in an inert hydrocarbon solvent such as hexane or heptane at a temperature of -40 to 150°C, preferably 0 to 100°C, and a reaction time of 5 minutes to 10 hours, preferably 20 minutes to 5 hours. All you have to do is react. Further, in the reaction of this reaction product () with the organoaluminum compound, an aromatic acid ester can be involved in the reaction if desired. The aromatic acid ester used here may be appropriately selected from those mentioned above, and the amount used is not particularly limited, for example, 0.01 to 0.5 (molar ratio) to the fatty acid salt in the reaction product (), preferably is 0.02~0.2
(molar ratio). The reaction product () obtained in this way is (A)
When used as a titanium-containing component, it becomes a polymerization catalyst with higher activity than when the reaction product () is used. According to the method of the present invention, (A), Polyolefin is produced by polymerizing olefin using a catalyst containing the two components B) as main components. In the polymerization of olefin, the reaction system contains the reaction product () or (), which is component (A), and
The organoaluminum compound as component (B) is added, 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). Further, 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 which are component (B) of the catalyst used in the method of the present invention. aluminum compounds and diethylaluminium monochloride,
Dialkyl aluminum monohalides such as diisopropylaluminum monochloride, dicysobutyl 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.
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 compound consumed during the preparation of the catalyst used is small, and almost all of the titanium compound used is utilized as a catalyst, 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. Moreover, since the magnesium salt in the catalyst also acts as a lubricant, the dispersibility of the catalyst into the polyolefin during the polymerization stage is improved, resulting in a homogeneous polyolefin. 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. [Example] Next, the present invention will be explained in more detail with reference to Examples. Example 1 (1) Preparation of titanium-containing component 40 ml of dehydrated n-heptane and magnesium stearate were placed in a 200 ml flask purged with argon.
4.0 g (6.8 mmol) and 0.16 g (0.68 mmol) of tetraethoxytitanium were added, heated, and reacted under reflux for 3 hours 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, add 400 ml of dehydrated n-heptane, 1 mmol of triethylaluminum, 1 mmol of diethylaluminum chloride, and 0.01 mmol of the titanium-containing component obtained in (1) above as a titanium atom. In addition, 80
The temperature was raised to .degree. C., and hydrogen was supplied so that the hydrogen partial pressure was 3 Kg/ ^cm.sup.2 . Next, the ethylene partial pressure is 5Kg/cm ²
Ethylene was continuously supplied so that the polymerization reaction was carried out for 1 hour to obtain 75 g of polyethylene. The results are shown in Table 1. Example 2 (1) Preparation of titanium-containing component The titanium-containing component (reaction product ()) obtained in Example 1 (1) was replaced with argon in an amount equivalent to 2.0 g (3.4 mmol) of magnesium stearate. Transfer 200ml to a flask and dehydrate n-
After diluting with 40 ml of heptane, it was cooled to about 5°C. Then, 0.41 g (3.4 mmol) of diethylaluminum chloride was gradually added dropwise to the solution for 30 min.
The mixture was reacted for a minute, then heated to 40° C. and reacted for 3 hours to obtain a titanium-containing component (reaction product ()). (2) Polymerization of olefin In Example 1 (2), the same procedure as Example 1 (2) was carried out except that 0.005 mmol of the titanium-containing component obtained in (1) above was used as a titanium-containing component. , 50 g of polyethylene was obtained. The results are shown in Table 1. Example 3 (1) Preparation of titanium-containing component 40 ml of dehydrated n-heptane and magnesium stearate were placed in a 200 ml flask purged with argon.
4.0g (6.8mmol), tetraethoxytitanium 0.16g
(0.68 mmol) and ethyl benzoate 0.051 g
(0.34 mmol) was added, and the temperature was raised and the reaction was carried out under reflux for 3 hours to obtain the entire amount of the reaction product as a titanium-containing component (reaction product (). (2) Polymerization of olefin In Example 1 (2) Above as titanium-containing ingredients
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 0.01 mmol was used. The results are shown in Table 1. Comparative Example 1 (1) Preparation of titanium-containing component In Example 1 (1), the amount of magnesium stearate used was 2.0 g (3.4 mmol) and the amount of tetraethoxytitanium used was 4.0 g (17 mmol).
A titanium-containing component was obtained in the same manner as in Example 1(1) except for the following. (2) Polymerization of olefin In Example 1 (2), 28 g of polyethylene was prepared in the same manner as in Example 1 (2) except that 0.1 mmol of the titanium-containing component obtained in (1) above was used as the titanium-containing component. I got it. The results are shown in Table 1. Example 4 (1) Preparation of titanium-containing component In Example 1 (1), tetraethoxytitanium
Except that 0.065 g (0.34 mmol) of titanium tetrachloride was used instead of 0.16 g (0.68 mmol).
A titanium-containing component (reaction product ()) was obtained in the same manner as in Example 1 (1). (2) Polymerization of olefin In Example 1 (2), as a titanium-containing component,
Using 0.005 mmol of the titanium-containing component (reaction product ()) obtained in (1) above as a titanium atom,
63 g of polyethylene was obtained in the same manner as in Example 1(2), except that the amounts of triethylaluminum and diethylaluminum chloride used were each changed to 0.5 mmol. The results are shown in Table 1.

【table】

【table】 [Brief explanation of the drawing]

FIG. 1 depicts the steps for preparing a catalyst using 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 magnesium fatty acid salt, 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, and X represents a halogen Indicates an atom.
Moreover, m is a real number greater than or equal to 0 and less than 4. ] A method for producing a polyolefin, which comprises using a reaction product ( ) obtained by adding and reacting a titanium compound represented by 0.5 or less (molar ratio). 2. In producing polyolefin by polymerizing olefin using a catalyst mainly composed of (A) a titanium-containing component and (B) an organoaluminum compound, (A)
As a titanium-containing component, for magnesium fatty acid salt, 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, and X represents a halogen Indicates an atom.
Moreover, m is a real number greater than or equal to 0 and less than 4. ] A reaction product ( ) obtained by adding and reacting a titanium compound represented by 0.5 or less (molar ratio)
, and the general formula R' _o AlX' _3-o [wherein R' represents an alkyl group, cycloalkyl group, or aryl group having 1 to 10 carbon atoms, and X' represents a halogen atom. Further, n represents a real number of 3 or less. ] A method for producing a polyolefin, which comprises using a reaction product ( ) obtained by reacting with an organoaluminum compound represented by the following.