JP2769711B2 - Method for producing catalyst component for olefin polymerization and method for polymerizing olefin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a high-performance catalyst composition having a high activity when used for polymerization or copolymerization of olefins. The present invention relates to a method for producing a catalyst component for olefin polymerization and a method for polymerizing olefin, which can obtain a highly stereoregular polymer in a high yield when applied to olefin polymerization.

[Conventional technology]

2. Description of the Related Art Conventionally, many solid catalyst components having magnesium, titanium, a halogen compound and an electron donor (internal donor) as essential components have been proposed. An organic carboxylic acid ester is often used, but there is a problem that an ester odor remains in the polymer unless an operation of removing the ester such as washing with an organic solvent is performed. It was also insufficient in terms of activity and stereospecificity.

In order to overcome these disadvantages, some specific esters, that is, esters having an ether moiety have been proposed. A method using anisates (JP-A-48-16986), a method using furancarboxylates (JP-A-59-129205, JP-A-54-136590), and a method using 2-ethoxyethyl acetate ( JP-A-61-2879
08 etc.) correspond to this. However, even if these esters are used, they do not have industrially satisfactory performance in terms of activity and stereospecificity, and further development of a high-performance catalyst has been desired.

[Problems to be solved by the invention]

Halogen, which is one of the solid catalyst components, has a drawback that corrosion of a molding machine or the like is promoted during polymer processing. Therefore, in order to suppress the corrosive action as much as possible, even if the catalyst removing step is omitted, a high activity that can ignore the influence of halogen is required, but from that point of view it is necessary to have sufficient performance. There are few things to say. Particularly, in a polymerization in which stereoregularity is a problem, a catalyst having high activity and high stereoregularity is desired.

[Means for solving the problem]

From the above, the present inventors have conducted various search studies to obtain an olefin polymer that has solved these problems, and as a result, during or after the formation of a solid catalyst component composed of magnesium, tetravalent titanium and halogen. The following general formula (I): R ¹ O—CH ₂ —Z—COOR ² (I) (where R ¹ is an alkyl group having 1 to 4 carbon atoms which may contain a branched chain, and R ² represents a branched chain. 1 to 1 carbon atoms that may be contained
An alkyl group of 10 and Z represents a divalent aromatic hydrocarbon group which may be a condensed polycyclic ring). The inventors have found that a polymer can be obtained by solving all of the above problems by polymerizing or copolymerizing an olefin using a polymerization catalyst component, and arrived at the present invention.

As the magnesium source used in the present invention, magnesium chloride such as magnesium chloride and magnesium bromide: ethoxymagnesium, alkoxymagnesium such as isopropoxymagnesium: magnesium carboxylate such as magnesium laurate and magnesium stearate : Magnesium compounds such as alkylmagnesium such as butylethylmagnesium. In addition, two of these compounds
It may be a mixture of more than one species. Preferably, a magnesium halide is used, or a magnesium halide is formed during catalyst formation. More preferably, the halogen is chlorine.

As the tetravalent titanium source used in the present invention,
Examples thereof include titanium halides such as titanium tetrachloride and titanium tetrabromide; titanium alkoxides such as titanium butoxide and titanium ethoxide; and tetravalent titanium compounds such as alkoxy titanium halides such as phenoxytitanium chloride. Also, a mixture of two or more of these compounds may be used. Preferred is a tetravalent titanium compound containing halogen, and particularly preferred is titanium tetrachloride.

The halogen source used in the present invention is a halogen compound in which the halogen is fluorine, chlorine, bromine or iodine, preferably chlorine, and when the magnesium compound or the tetravalent titanium compound contains a halogen, the halogen compound is a halogen compound. Can be a source. Specific compounds actually exemplified depend on the catalyst preparation method, but titanium tetrachloride, titanium halide such as titanium tetrabromide, silicon tetrachloride, silicon halide such as silicon tetrabromide, phosphorus trichloride, Representative examples include phosphorus halides such as phosphorus pentachloride, but halogenated hydrocarbons, halogen molecules, and hydrohalic acids (eg, HCl, HBr, HI, etc.) may be used depending on the preparation method.

The alkoxyester compound used in the present invention is represented by the general formula (I).

In the general formula (I), R ¹ is methyl, ethyl,
There are n-propyl, i-propyl, n-butyl, i-butyl and sec-butyl, and R ² is methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl , T-butyl, pentyl, hexyl, 3-methylpentyl, tert-pentyl, heptyl,
Examples thereof include i-hexyl, octyl, nonyl, and decyl.

As Z in the general formula (I), o-phenylene, m-phenylene, p-phenylene, 2,5-dimethyl-o-phenylene, 1,2-naphthylene, 2,3-naphthylene, 1,8-naphthylene, 1,8-fluorenediyl, 4,5-phenanthrylene, 1,9-anthracenediyl, biphenyldiyl,
1,7-indendiyl, 2,5-thiophenediyl, 3,4-
Examples include pyrrole diyl and 2,3-flange yl.

The following are specific compounds: ethyl 2- (methoxymethyl) -benzoate, 2- (t-butoxymethyl)-
N-butyl benzoate, methyl 2- (ethoxymethyl) -1-phthaleneacetate, butyl 8- (methoxymethyl) naphthalene-1-carboxylate, ethyl 5- (butoxymethyl) phenanthrene-4-carboxylate, and the like, As particularly preferred compounds, specifically, ethyl 2- (t-butoxymethyl) benzoate, ethyl 8- (methoxymethyl) naphthalene-1-carboxylate, 5- (ethoxymethyl)
Examples thereof include ethyl phenanthrene-5-carboxylate.

Although the catalyst preparation method used in the present invention is not particularly limited, the magnesium halide, the titanium halide and the `` alkoxy ester compound '' may be co-ground, followed by a halogenation treatment, and high activation may be measured. .
Magnesium halide alone or after co-milling with a magnesium halide and a silicon compound or a phosphorus compound,
Titanium compound treatment and halogenation treatment may be performed in the presence of the “alkoxy ester compound”. Also, magnesium carboxylate or alkoxy magnesium and a titanium compound, a halogenating agent and an “alkoxy ester compound”
May be heat-treated to improve the performance. The magnesium halide may be dissolved in an organic solvent or the like, and the “alkoxy ester compound” may be allowed to act during or after the precipitation in the presence of the titanium compound. When a halogenating agent is allowed to act on the alkyl magnesium, an “alkoxy ester compound”
A catalyst formed by adding a titanium compound to the preparation process may be used.

The amount of the "alkoxy ester compound" remaining in the catalyst depends on the preparation method, but when the "alkoxy ester compound" is abbreviated as ID, titanium: magnesium: ID (molar ratio) is 1: 1 to 1000: 10 ^{-6 to} 100 And in the range of 1: 2 to 100: 10 ^-4 to 10. If the ID is less than this range, stereospecificity decreases, while if it is too large, the activity decreases, which is not preferable.

Polymerization of olefin The solid catalyst component of the present invention obtained as described above includes:
By combining with an organic aluminum compound, olefin polymerization can be performed.

Representative examples of the organoaluminum compound in the present invention are represented by the following general formulas (II) to (IV).

In the formulas (II), (III) and (IV), R ³ , R
⁴ and R ⁵ may be the same or different and have at most 12 carbon atoms a hydrocarbon group, a halogen atom or a hydrogen atom,
At least one of them is a hydrocarbon radical, R ⁶ ,
R ⁷ , R ⁸ and R ⁹ may be the same or different and have at most 12 hydrocarbon groups with carbon nests.

R ¹⁰ is a hydrocarbon group having at most 12 carbon atoms, and j is an integer of 1 or more.

Representative examples of the organoaluminum compounds represented by the formula (II) include trialkylaluminums such as triethylaluminum, tripropylaluminum, tributylaluminum, trihexylaluminum and trioctylaluminum, and further, diethylaluminum hydride and diisobutylaluminum hydride. And alkylaluminum halides such as diethylaluminum chloride, diethylaluminum bromide and ethylaluminum sesquichloride.

Representative examples of the organoaluminum compound represented by the formula (III) include alkyldialumoxanes such as tetraethyldialumoxane and tetrabutyldialumoxane.

Formula (IV) represents aluminoxane, which is a polymer of an aluminum compound. R ¹⁰ is methyl, ethyl,
Including propyl, butyl, pentyl and the like, preferably a methyl or ethyl group. n is preferably 1 to 10.

Of these organoaluminum compounds, trialkylaluminums, alkylaluminum hydrides and alkylalumoxanes are preferred, and trialkylaluminums are particularly preferred because they give favorable results.

A catalyst comprising a titanium-containing solid catalyst component according to the present invention and a catalyst component comprising an organoaluminum compound for the purpose of improving the stereoregularity of the resulting polymer when performing a polymerization reaction of an α-olefin having 3 or more carbon atoms. Many stereoregularity improvers which have been proposed for use in Ziegler polymerization catalysts and which have the effect of improving stereoregularity can be further added to the system. Examples of the compound used for such a purpose include an aromatic monocarboxylic acid ester, a silicon compound having a Si-OC or Si-NC bond, an acetal compound, a germanium compound having a Ge-OC bond, and an alkyl compound. Examples of the substituent include a nitrogen or oxygen heterocyclic compound having a substituent.

Specifically, for example, ethyl benzoate, butyl benzoate, ethyl p-toluate, ethyl p-anisate, phenyltrimethoxysilane, phenyltriethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, di-n-propyl Dimethoxysilane, cyclohexylmethyldimethoxysilane, tetraethoxysilane, t-butylmethyldimethoxysilane, benzophenone dimethyl acetal, benzophenone diethyl acetal, acetophenone dimethyl acetal, t-butyl methyl ketone dimethyl acetal, diphenyldimethoxygermane, phenyltriethoxygermane, 2, 2,6,6
-Tetramethylpiperidine, 2,2,6,6-tetramethylpyran and the like. Particularly preferred as these stereoregularity improvers, ie, electron donors, are compounds corresponding to silane compounds, acetal compounds and piperidine compounds.

Accordingly, the present invention provides the above catalyst component, and further comprises polymerizing an olefin using a catalyst system comprising the above catalyst component, an alkylaluminum compound and an electron donor selected from a silane compound, an acetal compound and a piperidine compound. And a method for producing an olefin polymer.

Usage Ratio In the polymerization of olefins, the amount of organoaluminum used in the polymerization system is generally 10 ⁻⁴ mmol / or more, and preferably 10 ⁻² mmol / or more. Further, the usage ratio to the titanium atom in the solid catalyst component is generally 0.5 or more, preferably 2 or more, particularly 1
0 or more is preferable. If the amount of the organic aluminum is too small, the polymerization activity is significantly reduced.
The amount of organic aluminum used in the polymerization system was 20%.
When the molar ratio is at least mmol / mol and the ratio to the titanium atom is at least 1,000, the catalyst performance will not be further improved even if these values are further increased.

The amount of the above-mentioned stereoregularity improver used for the purpose of improving the stereoregularity of the α-olefin polymer can be achieved with a very small amount by using the titanium-containing solid catalyst component of the present invention. It is usually 0.001 to 5 mol per 1 mol of the organoaluminum compound,
It is preferably used in a ratio of 0.01 to 1.

Olefin The olefin used for the polymerization is generally an olefin having at most 18 carbon atoms, and typical examples thereof include ethylene, propylene, butene-1, 4-methylpentene-1, hexene-1, octene and octene. -1 and the like. In carrying out the polymerization, these olefins may be homopolymerized, or two or more olefins may be copolymerized (for example, copolymerization of ethylene and propylene).

Polymerization Method and Its ConditionsIn carrying out the polymerization, the solid catalyst component of the present invention, the organoaluminum compound or these and the silicon compound may be separately introduced into a polymerization vessel, but two or all of them may be introduced in advance. You may mix.

Polymerization in an inert solvent, liquid monomer (olefin)
It can be performed in either the medium or gas phase. In order to obtain a polymer having a practical melt flow,
A molecular weight regulator (generally, hydrogen) may coexist.

The polymerization temperature is generally from -10 ° C to 180 ° C, and practically from 20 ° C to 130 ° C.

In addition, the form of the polymerization reactor, the method of controlling polymerization, the method of post-treatment, and the like are not limited to those specific to the present catalyst system, and all known methods can be applied.

〔Example〕

 Hereinafter, the present invention will be described in more detail with reference to examples.

In the examples and comparative examples, the heptane index (that is, HR) is boiling n-heptane, and represents the remaining amount after extracting the obtained polymer for 6 hours in%. Melt flow ratio (or MFR)
0.2% of 2,6-di-tert-butyl-4-methylphenol
The temperature of the mixed powder is 230 according to JIS K-6758.
It measured under the conditions of ° C and a load of 2.16 kg.

In each of the examples, each of the compounds (organic solvent, olefin, hydrogen, titanium compound, magnesium compound, stereoregularity improver, etc.) used in the production and polymerization of the solid catalyst component is substantially water-free. .

Further, the production method and polymerization of the solid catalyst component were carried out in a nitrogen-free atmosphere substantially without water.

(Example 1) Preparation of solid catalyst component 20 g (0.21 mol) of anhydrous magnesium chloride (obtained by calcining and drying commercially available anhydrous magnesium chloride in a stream of dry hydrogen chloride gas at about 500 ° C for 15 hours) -(Tert-butoxymethyl) -ethyl benzoate
11.8 g (0.05 mole), 3.3 ml of titanium tetrachloride and 3.0 ml of silicon oil (TSS-451.20CS manufactured by Shin-Etsu Chemical Co., Ltd.) as a grinding aid
Was placed in a container for a vibrating ball mill (stainless steel cylindrical type, circular volume 1, magnetic ball having a diameter of 10 mm and apparent volume filled by about 50%) under a dry nitrogen stream. This is the amplitude
A co-ground solid was obtained by attaching to a 6 mm vibrating ball mill and co-milling for 15 hours. 15 g of the obtained co-ground product was suspended in 150 ml of 1.2-dichloroethane, and
After stirring at 2 ° C. for 2 hours, the solid portion was collected by filtration,
The plate was washed sufficiently with hexane until free 1.2-dichloroethane was not detected in the washing solution. 30 ℃
After drying under reduced pressure at 40 ° C. to remove hexane, a solid catalyst component was obtained. When the obtained solid catalyst component was analyzed, the content of titanium atoms in this solid catalyst component was 2.7% by weight.

Polymerization and physical properties of the resulting polymer In a stainless steel autoclave having an internal volume of 3, 20 mg of the solid catalyst component produced in the above-described manner, 91 mg of triethylaluminum and 20 mg of diphenyldimethoxysilane, and immediately, 760 g of propylene and 0.1 g of 0.1 g Hydrogen was charged. The temperature of the autoclave was raised and the internal temperature was kept at 70 ° C. After one hour, the content gas was released to terminate the polymerization. As a result, 219 g of powdery polypropylene was obtained. That is, the polymerization activity is 11000 g / g solid catalyst component / hour and 405 kg / g-Ti · hour.

The HR of this polypropylene powder was 95.1%.
The MFR was 12.3 g / 10 minutes.

(Example 2) Using the solid catalyst component of Example 1, the polymerization temperature was set to 80 ° C. Other than that is the same as the first embodiment. The obtained polymer is a powdery polymer of 308 g, and the polymerization activity is 15400 g / g.
Solid catalyst component / hour, 570 kg / g-Ti · hour. The HR of this polypropylene powder is 96.5% and the MFR is 7.7 g / 10
Minutes.

(Example 3) Using the solid catalyst component of Example 1, polymerization was carried out in the same manner as in Example 1 except that 20 mg of phenyltriethoxysilane was charged instead of diphenyldimethoxysilane during the polymerization. From the obtained powder polymer, the polymerization activity is 10800 g / g
Solid catalyst component / hour, 400 kg / g-Ti / hour, HR9
5.0%, MFR was 4.1 g / 10 min.

(Examples 4 to 7) The same polymerization conditions as in Example 1 were used except that the solid catalyst component of Example 1 was used and the stereoregularity improver added during the polymerization was changed as shown in Table 1. The results obtained are also shown in Table 1.

Example 8 9.5 g of anhydrous magnesium chloride (treated in the same manner as in Example 1) was mixed with 50 ml of decane and 46.8 ml of 2-ethylhexyl alcohol at 130 ° C. in a round-bottom flask under N ₂ atmosphere. For 2 hours. 2.1 g of phthalic anhydride was added, and the mixture was further heated at 130 ° C. for 1 hour. This solution was cooled to room temperature, 20 ml was charged into a dropping funnel, and -20 ° C over 30 minutes.
Was dropped into 80 ml of titanium tetrachloride, and the temperature was raised to 110 ° C. in 4 hours. A solution of 1.04 g of ethyl 2 (tert-butoxymethyl) -benzoate was slowly added dropwise. After dropping,
The reaction was performed at 110 ° C. for 2 hours. After removing the supernatant, re-add T
80 ml of iCl ₄ was introduced and heated at 110 ° C. for 2 hours. Then 100
After washing three times with ml of n-decane, the solid was washed with n-hexane to obtain a solid catalyst. The Ti loading was 3.1% by weight.

As a result of carrying out the polymerization in the same manner as in Example 1, the polymerization activity was 10
It was 800 g / g solid catalyst · hour and 348 kg / g-Ti · hour.
The HR was 96.3% and the MFR was 2.9 g / 10 min.

(Example 9) In a nitrogen stream, a well-dried 300 ml round bottom flask was
100 ml of n-heptane, 9.5 g of MgCl _{2, and} 68 g of Ti (O-nBn) ₄ were added, and reacted at 100 ° C. for 2 hours to obtain a homogeneous solution. After the completion of the reaction, the temperature was lowered to 40 ° C., and then 15 ml of methyl hydrogen polysiloxane (of 20 centistokes) was added and reacted for 3 hours. After washing the formed solid catalyst with n-heptane, 150 ml of heptane was added, and a solution prepared by dissolving 28 g of SiCl ₄ in 80 ml of n-heptane was added dropwise over 1 hour at room temperature. After the completion of the dropwise addition, the reaction was further performed for 30 minutes. The obtained solid component was washed three times with 200 ml of n-heptane, and then cooled to -10 ° C. To this was a TiCl ₄ introduced 100 ml, well after stirring, 2-(tert-butoxymethyl) of 3.00 g - was added dropwise ethyl benzoate. After the completion of the dropwise addition, the reaction was carried out at 90 ° C. for 2 hours. Remove the supernatant, introduce 100 ml of fresh TiCl ₄ and add 9 ml.
The reaction was performed at 0 ° C. for 2 hours. After completion of the reaction, the solid was washed with n-heptane to obtain a solid catalyst. Analysis of the amount of Ti carried was 2.7% by weight.

The polymerization was carried out in the same manner as in Example 1. As a result, the polymerization activity was 8430 g / g / solid catalyst / hour, and 312 kg / g-Ti / hour. The HR was 94.7% and the MFR was 18 g / 10 minutes.

(Example 10) In a nitrogen stream, a sufficiently dried 300 ml round bottom flask was
5 g of diethoxymagnesium, 1.30 g of ethyl 2- (tert-butoxymethyl) -benzoate and 25 ml of methylene chloride were added. Stir at reflux for 1 hour and then allow the suspension to cool to room temperature.
It was pumped 200ml to the TiCl ₄ in. The temperature was gradually raised to 110 ° C., and the reaction was carried out with stirring for 2 hours. After completion of the reaction, the precipitated solid was separated by filtration and washed three times with 200 ml of n-decane at 110 ° C. 200 ml of fresh TiCl ₄ was added and reacted at 120 ° C. for 2 hours. After the completion of the reaction, the precipitated solid was separated by filtration, and then washed with 200 ml of n-decane at 110 ° C.
Washed twice and washed with hexane at room temperature until no chloride ion was detected with n-hexane. The titanium atom content of this catalyst component was 3.3.

The polymerization was carried out in the same manner as in Example 1. When calculated from the obtained results, the polymerization activity was 17800 g / g solid catalyst / hour, 539 k
In g / g-Ti · hour, HR was 96.5% and MFR was 1.8 g / 10 minutes.

(Examples 11 to 14, Comparative Examples 1 to 4) Instead of 2 (tert-butoxymethyl) -ethyl benzoate of Example 10, the components added during the preparation of the catalyst were changed. Other than that was prepared like Example 10. The polymerization method was as described in Example 1.
The same was done. Table 2 shows the polymerization results.

(Example 15) Using the solid catalyst of Example 1, polymerization was carried out in the same manner as in Example 1 without using diphenyldimethoxysilane. The polymerization activity of the obtained polymer was 13800 g / g · solid catalyst · hour and 511 kg / g-Ti · hour. The powder HR of this polypropylene was 48.9%. The MFR was 23.9 g / 10 minutes.

Comparative Example 5 A catalyst was prepared in the same manner as in Example 1 without using 2- (tert-butoxymethyl) -ethyl benzoate. Polymerization was carried out in the same manner as in Example 1 without using diphenyldimethoxysilane. The polymerization activity of the obtained polymer was 9110 g / g · solid catalyst · hour and 285 kg / g-Ti · hour. The HR · of this polypropylene powder was 23.7%. The MFR was 7.9 g / 10 minutes.

(Comparative Example 6) A solid catalyst was prepared in the same manner as in Example 1 without using ethyl 2- (tert-butoxymethyl) -benzoate. Polymerization was carried out in the same manner as in Example 1. The polymerization activity of the obtained polymer was 4910 g / g · solid catalyst · hour and 213 kg / g-Ti · hour. The HR of this polypropylene powder was 71.2%. The MFR was 3.8 g / 10 minutes.

(Example 16) Instead of 2 (tert-butoxymethyl) -ethyl benzoate of Example 10, the additional component at the time of catalyst preparation was changed to 2 (ethoxymethyl) -octyl benzoate. Other examples
Prepared similarly to 10. The polymerization method was the same as in Example 1. The obtained results show that the polymerization activity is 15600 g / g
In time, the HR was 96.1% and the MFR was 4.3 g / 10 min.

〔The invention's effect〕

When olefins are polymerized using the catalyst component obtained according to the present invention, the catalyst has a very high activity, so that the catalyst residue in the produced polymer can be kept extremely low. Can be omitted.
Further, since the amount of remaining Cl (concentration) is small, the degree of corrosion of a molding machine or the like in a polymer processing step can be significantly modified. Further, the residual catalyst causes deterioration and yellowing of the polymer itself, but since the concentration is necessarily low, these can be reduced.

In addition, since the stereoregularity is high, a polymer having practically usable mechanical strength can be obtained without removing a so-called atactic portion.

These effects are of crucial significance in industrial processes.

[Brief description of the drawings]

FIG. 1 is a flow chart of one olefin polymerization catalyst composition of the present invention.

Continuation of front page (58) Field surveyed (Int. Cl. ⁶ , DB name) C08F 4/658 C08F 10/00

Claims (2)

(57) [Claims] The present invention relates to the following general formula (I): R ¹ O—CH ₂ —Z—COOR ² (I) wherein R ^{1 is a} solid catalyst component comprising magnesium, tetravalent titanium and halogen. Is an alkyl group having 1 to 4 carbon atoms which may have a branched chain, and R ² has 1 to 4 carbon atoms which may have a branched chain.
An alkyl group of 10 and Z represents a divalent aromatic hydrocarbon group which may be a condensed polycyclic ring). A method for producing a polymerization catalyst component. 2. An olefin obtained by polymerizing an olefin using a catalyst system comprising the catalyst component according to claim 1, an alkylaluminum compound, and an electron donor selected from a silane compound, an acetal compound and a piperidine compound. A method for producing a polymer.