JPH0374415A - Production of highly stereoregular polypropylene - Google Patents

Abstract

PURPOSE:To obtain a highly stereoregular polypropylene having good particle properties and high bulkiness with high activity even in using low amount of alumoxane by polymerizing propylene using a catalyst consisting of a specific organometallic compound and an alumoxane-carrying inorganic oxide support. CONSTITUTION:Propylene is polymerized using a catalyst consisting of (A) an organometallic compound [preferably ethylene bis-(indenyl)zirconium chloride] expressed by the formula (R1 is 1-20C hydrocarbon group; R2 is hydrocarbon group, etc.; M is titanium, etc.; X is halogen or hydrocarbon group; n is 1-4; m is 0-4; 1 is 0-2) and (B) an inorganic oxide support (preferably silica) carrying alumoxane to provide the highly stereoregular polypropylene in high yield.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention uses a catalyst that combines a catalyst component that is a specific transition metal compound and a catalyst component that has alumoxane supported on an inorganic oxide carrier, and uses a catalyst that has particle size characteristics. The present invention relates to a method for producing polypropylene with excellent properties and high stereoregularity in high yield.

[Conventional technology]

Conventionally, catalysts consisting of sterically fixed zirconocene, such as ethylenebis(indenyl)zirconium dichloride and methylalumoxane, are known to give highly active and highly stereoregular polyα-olefins.

(Japanese Unexamined Patent Publication No. 61-130314), and highly stereoregular polyα-olefin produced by using a catalyst consisting of a combination of a catalyst component in which this zirconocene is supported on an inorganic compound such as silica, and methylalumoxane. It is known that the particle properties of

(Unexamined Japanese Patent Publication No. 63-66206) [Problem to be solved by the present invention] In these catalyst systems consisting of sterically fixed metallocene and alumoxane, highly stereoregular polypropylene can be used to eliminate the catalyst removal step. The discovery that it can be produced with sufficiently high activity is extremely noteworthy, but there are various issues to be solved before turning it into an industrial technology.
In particular, the occurrence of scale, which is thought to be caused by the homogeneous catalyst, and the irregular particle shape of the polymerized powder have been pointed out as one of the major problems. In addition, in order to solve this problem, many methods have been tried in which the metallocene side is supported on an inorganic oxide, etc., but in this case, there is a problem that the activity is significantly reduced.

[Means to solve the problem]

As a result of repeated research to solve the above-mentioned problems, the present inventors have developed a method of supporting an organic aluminum component on an inorganic oxide (Japanese Unexamined Patent Publication No. 61-276805), which has already been discovered by the present inventors. It was found that when applied to a catalyst system, a highly stereoregular polypropylene with relatively little reduction in activity and excellent particle size characteristics could be obtained. As a result of further consideration,
As a method for supporting an organoaluminum component on an inorganic oxide, particle size characteristics can be further improved by removing unreacted organoaluminum components and then using them for polymerization. The present invention was accomplished by discovering that by supporting methylalumoxane after contact, a polymer with extremely excellent particle size characteristics can be obtained without reducing activity.

That is, the present invention provides: (1) In producing highly stereoregular polypropylene by polymerizing propylene in the presence of a catalyst, as a catalyst, (A) - formula (in the formula, R1 has 1 to 20 carbon atoms) a hydrocarbon group,
When two R1's are present at adjacent positions on the cyclopentagenyl ring, they may be combined to form a carbocyclic ring, and R1! is a hydrocarbon group or a thioaryl group, and when two of these exist, the carbon atoms thereof may be bonded to each other directly or through a sulfur atom, and M is titanium, zirconium, or hafnium. and
X is a hydrocarbon group or a halogen atom, n is an integer of 1 to 4, m is O or an integer of 1 to 4, l is O or an integer of 1 or 2), and (B) A method for producing highly stereoregular polypropylene characterized by using a catalyst consisting of an inorganic oxide carrier supporting alumoxane (2) The catalyst component (B) is an organic aluminum compound brought into contact with the inorganic oxide carrier in advance. This is a method for producing highly stereoregular polypropylene according to item (1) above, which is a component obtained by supporting alumoxane, particularly methylalumoxane.

The present invention will be explained in detail below.

The catalyst used in the method of the present invention is formed from a combination of the components (A) and (B), and
As the component (A), an organometallic compound represented by the above formula (1) is used.

Each cyclopentadienyl group in formula (1) above is R1, that is, a hydrocarbon group having 1 to 20 carbon atoms 1
Specific examples of this hydrocarbon group which may be substituted with ~4 groups include, for example, a methyl group, an ethyl group, a propyl group,
Aliphatic, alicyclic, and Mention may be made of aromatic hydrocarbon groups. In addition, when two R- are present in adjacent positions of each cyclopentagenyl ring, they bond to each other to form a carbocyclic ring, and together with the cyclopentagenyl ring, an indenyl group, a hydrogenated indenyl In the present invention, it is particularly preferable to use those having such an indenyl group or hydrogenated indenyl group as (A) 1, and furthermore, two cyclopentadienyl groups. The alkylene group bonding has 1 to 4 carbon atoms, and examples of such groups include,
Methylene group, ethylene group, 1.3-propylene L 1.
Examples include linear or branched alkylene groups such as 2-propylene, 1,4-butylene, and 2,3-butylene, and among these, ethylene is particularly preferred.

Further, M in formula (1) is titanium, zirconium or hafnium, and among these, zirconium and hafnium are preferred, and zirconium is particularly preferred.

R1 in the above formula (1) is a hydrocarbon group or a thioaryl group, and when this is a hydrocarbon group, for example, a methyl group, an ethyl group, a propyl group, a butyl group, an isobutyl group, a t-butyl group, Examples include amyl group, isoamyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, cetyl group, phenyl group, and substituted phenyl group. Furthermore, when two R1's exist, the carbon atoms therein may be bonded to each other directly or via a sulfur atom.

X in the above-mentioned formula (1) is a hydrocarbon group or a halogen atom, and specific examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, an isobutyl group, a t-butyl group, an amyl group, and an isoamyl group. , aliphatic and aromatic hydrocarbon groups such as hexyl group, heptyl group, octyl group, nonyl group, decyl group, cetyl group, phenyl group, and halogen atoms such as chlorine, bromine, and iodine.
Among these, chlorine is particularly preferred.

Specific examples of the compound represented by formula (1) include methylenebis(cyclopentagenyl)titanium dichloride, ethylenebis(cyclopentagenyl)titanium dichloride, propylenebis(cyclopentagenyl)titanium dichloride, tetra Methylethylenebis(cyclopentagenyl)titanium dichloride, ethylenebis(indenyl)titanium dichloride, ethylenebis(tetrahydroindenyl)titanium dichloride, methylenebis(cyclopentagenyl)zirconium dichloride, ethylenebis(cyclopentagenyl)zirconium dichloride , Propylenebis(cyclopentagenyl)zirconium dichloride, Tetramethylethylenebis(cyclopentagenyl)zirconium dichloride, Ethylenebis(indenyl)zirconium dichloride, Ethylenebis(indenyl)zirconiumdimethyl, Ethylenebis(indenyl)zirconiumdiethyl, Ethylene Bis(indenyl)zirconium jetoxide, ethylenebis(indenyl)zirconium jetoxide, ethylenebis(indenyl)zirconium jetoxide, ethylenebis(indenyl)propoxyzirconium chloride, ethylenebis(indenyl)zirconium jetoxide, ethylenebis(indenyl) Butoxyzirconium chloride, ethylene bis(
Tetrahydroindenyl) dichloride, ethylenebis(
tetrahydroindenyl) zirconium jetoxide,
Ethylenebis(tetrahydroindenyl)propoxyzirconium chloride, ethylenebis(tetrahydroindenyl)zirconium jetoxide, ethylenebis(tetrahydroindenyl)butoxyzirconium chloride, ethylenebis(indenyl)zirconium-1,1'
-B2-ferulate, ethylenebis(indenyl)
Zirconium-1,1'-bi-2-naphtholate, ethylenebis(indenyl)zirconium-4,4'-fudimethyl-66'-di-t-butyl-2,2'-methylene diperlate, ethylenebis(indenyl) Zirconium-4,4'-dimethyl-6,6'-di-t-butyl-2,2'-thiophelate, ethylenebis(tetrahydroindenyl)zirconium-1,1'-bi-2-
Ferulate, ethylenebis(tetrahydroindenyl)zirconium-1,l'-bi-2-naphtholate, ethylenebis(tetrahydroindenyl)zirconium-
4,4'-Fujimethyl-66'-di-t-butyl-2,
21-methylene diperlate, ethylene bis(tetrahydroindenyl) zirconium-4,4'-dimethyl-6,6'-di-t-butyl-2,2'thiophelate, ethylene bis(indenyl) hafnium dichloride,
Examples include ethylenebis(tetrahydroindenyl)hafnium dichloride, among which ethylenebis(indenyl)zirconium dichloride and ethylenebis(indenyl)hafnium dichloride are preferred.

These metallocene compounds can be prepared using known methods such as JP-A-6-1-130314 and JP-A-63-25140.
It can be produced according to the method described or cited in Publication No. 5 and the like.

Next, (B) 1 minute will be explained.

In component (B), the alumoxane is supported on an inorganic oxide support. As the carrier, a porous inorganic oxide is preferable, and specifically, for example, silica, silica/alumina,
Examples include alumina and magnesia, and silica is preferably used. Particularly preferred are those with a specific surface area of 200 nf/g or more.There are no restrictions on the surface hydroxyl groups of these inorganic oxides, but 0.05 to 5 tamo10H/g
The preferred range is , and those within this range can be easily obtained by drying the above-mentioned inorganic oxide at, for example, 150 to 700° C. under vacuum, air or nitrogen flow.

In the present invention, it is particularly preferable in the present invention to carry out a treatment in which the support is brought into contact with an organoaluminum compound in advance, prior to the reaction of supporting alumoxane on the inorganic oxide.

Specific examples of organic aluminum compounds include trialkylaluminium such as trimethylaluminum, triethylaluminum, and triisobutylaluminum, alkenylalkenium such as isoprenylaluminum, dimethylaluminum methoxide, and diethylaluminum ethoxy. Examples include alkoxylated alkyl aluminums such as chloride, halogenated alkyl aluminums such as diethylaluminum chloride and ethyl aluminum sekis chloride, and alumoxanes such as methylalumoxane and isobutylalumoxane. be.

In the present invention, the contact ratio of the organic aluminum compound to the inorganic oxide support is 1 to 20 smoj in terms of aluminum atoms per 1 g of the inorganic oxide support! AI, preferably 1-10 wmol Al.

Next, specifically, the alumoxane supported on the inorganic oxide carrier is, for example, by the formula (where R is a hydrocarbon group having 1 to 4 carbon atoms, p is 1 to
) is an integer of . Examples of R in formulas (II) and (III) include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, 5ec-
Examples include lower alkylene groups such as butyl group and t-butyl group, but among these, methyl group is particularly preferred, and p is preferably 5 or more, more preferably 5 to 5.
It is 20.

Such alumoxane is generally obtained by reacting trialkylaluminum and water, but there are no particular restrictions on the method for producing it, and any known method can be used.

For example, trialkylaluminum is dissolved in a hydrocarbon solvent and gradually brought into contact with an equivalent amount of water, or copper sulfate permanent or aluminum sulfate hydrate is suspended in a hydrocarbon solvent and 1 to 3 times the amount of water is added. Examples include a method of mildly hydrolyzing trialkylaluminum using crystal water.

The contact ratio of alumoxane to the inorganic oxide support in the present invention is 1 to 40111 IIolAl, preferably 1 to 20 +11101 AI, in terms of aluminum atoms, per 1 g of the inorganic oxide support.

In the present invention, methods for preparing an inorganic oxide carrier on which alumoxane is supported include, for example, (1) a method of reacting alumoxane and an inorganic oxide carrier in an inert hydrocarbon solvent such as toluene; A method of mixing an organoaluminum compound and an inorganic oxide carrier in an inert hydrocarbon solvent such as toluene at room temperature or under heating conditions, and then reacting the alumoxane. (3) Organoaluminum compound and alumoxane (4) A method of mixing alumoxane and an inorganic oxide carrier in an inert hydrocarbon solvent such as toluene at room temperature or under heating conditions, and then reacting the mixture with an inorganic oxide carrier. Although any method of mixing the organic aluminum compound in an inert hydrocarbon solvent at room temperature or under heating conditions can be used, it is preferable to use the method (2). be.

The solid component obtained by the above reaction is separated by filtration or decane silane method, and then thoroughly washed with an inert hydrocarbon solvent such as toluene to remove unreacted substances or by-products. In 1 g of the thus obtained catalyst component (B), which is particularly preferred in the present invention, there are usually 2 to 10 vso! aluminum atoms. carried.

In the present invention, it is preferable that 1 to 10 mmol of aluminum atoms derived from alumoxane are supported.

Next, the usage amount of each catalyst component will be explained.

In the method of the present invention, the component (A) is preferably used in a form solubilized in an inert hydrocarbon solvent such as toluene, and usually has a transition metal atom of 10-" to 10-' m
ol/L, preferably 10-' to 10-'mol/
It is used in a proportion that gives a concentration of L. On the other hand, the component (B) is used in such a ratio that the aluminum atom/transition metal atomic ratio is usually in the range of 1 to 10h1, preferably 1 to 104, relative to the 7'lJc portion of (A). . Furthermore, in the present invention, even when the aluminum atom/transition metal atomic ratio is as low as about 1 to 200,
Polymerization can be carried out with sufficiently high activity.

In the production method of the present invention, the component (A) and (B) J
There are no particular restrictions on how to form or use the catalyst consisting of 1 min. For example, in the method of the present invention, catalyst components (A) and (B) may be separately supplied to the polymerization system. However, in the present invention, the two catalyst components may be mixed in advance and then fed to the polymerization system.
It is preferable to feed catalyst components (A) and (B) separately to the polymerization system.

The polymerization method used in the present invention is not particularly limited and can be carried out in either liquid phase or gas phase. When carrying out liquid phase polymerization, an inert solvent such as benzene or toluene may be used as the reaction medium, but propylene itself may also be used as the reaction medium. Further, there is no particular restriction on the polymerization method, and the polymerization may be performed in a batch manner or in a continuous manner.

The polymerization temperature in the present invention is usually -80'C to 1
00°C, preferably in the range of -20°C to 8°C.

The polypropylene thus obtained has a +meso-5eso sequence fraction of 90 in the total triand chain.
It has a high stereoregularity of more than %.

〔Example〕

Examples of the present invention will be shown below, but the present invention is not limited to these Examples in any way.

In addition, the fraction in the examples and tables represents the stereoregularity of the produced polymer, and the polymer was dissolved in O-dichlorobenzene and 13C-NMR was conducted using JEOL 1IGX-270Q at 135°C. All triads obtained from analysis
Shown as the fraction of 1Ie30-1eljso sequences in the chain.

Example 1 (1) Synthesis of alumoxane at the base of alumoxane According to Example 1 of JP-A-58-19309, the following reaction was carried out under a nitrogen stream.

37.5g (0.15mol) of Cu5O*”
5 HzO (equivalent to H80 of 0.75 sol)
After suspending it in 250 mL of toluene, 50 m
L (0.52 mol) of trimethylaluminum was added and reacted for 24 hours at 20°C with stirring.Methane gas generation was observed during the reaction.After the reaction, copper sulfate was filtered off and toluene was removed from the filtrate. and 13.0g (theoretical value 4
4%> of methylalumoxane was obtained. The molecular weight of this product was determined to be 640 by the freezing point depression method in benzene.
, the average degree of oligomerization was 11.

(2) The bottom of the solid catalyst component (B) was placed in a 50 mL flask that had been sufficiently purged with nitrogen.
1 g of silica (Fuji Davison Grade 952 calcined at 300°C for 4 hours) suspended in 0 mL and 1 mol/L of trimethylaluminum) toluene solution 4 ml
Add L (4 smol) and heat at 80°C under nitrogen stream for 2 hours.
Allowed time to react. After that, 6 mL of 2.7 s+ol/L toluene solution of methylalumoxane that bottomed out in (1)
(16s+no!) was added and the reaction was further carried out for 2 hours. After the completion of the reaction, the solid was separated by a decantation method, thoroughly washed with toluene, and made into a toluene slurry, which was used as a solid catalyst component (B-1). When a part of this was collected and analyzed, the AI content per 1 g of solid catalyst component was 4.5 ms+ol.

(3) Polymerization of propylene 500 mL of liquid propylene was introduced at room temperature into a 1.5 L autoclave that had been thoroughly purged with nitrogen and dried under vacuum.
The temperature was raised to ℃. Continued to be 0.6 in terms of aluminum atoms.
Toluene slurry (B-1) containing the solid catalyst component (2) equivalent to 7 mmol and ethylene bis(indenyl)zirconium dichloride (2s + sol equivalent to 0.004 mmol in terms of zirconium atoms)
/L) J renin solution (2 mL) was charged, and polymerization was performed for 1 hour. After polymerization, unreacted propylene was removed, hydrochloric acid-methanol was added, and the polymer was filtered out.
Dry. The yield of polypropylene thus obtained was 120 g, and the catalytic activity was 30000 g/
smol Zr-hr.

The bulk density of the polymer was 0.37 g/cj. It should be noted that no polymer was observed to adhere to the inside of the autoclave. Further, the fraction of this polymer was found to be 93.0% by C-NMR analysis. The results are shown in Table 1.

Example 2 In the production of the CB catalyst component in (2) of Example 1, the entire procedure was carried out in the same manner as in Example 1, except that triethylaluminum was used instead of trimethylaluminum. Shown in the table.

Example 3 The same procedure as in Example 1 was carried out except that triisobutylaluminum was used instead of trimethylaluminum in the production of the catalyst component (B) in (2) of Example 1. The results are shown in Table 1.

Example 4 The entire process was carried out in the same manner as in Example 1, except that methylalumoxane was used instead of trimethylaluminum in the production of the catalyst component (B) in (2) of Example 1. The results are shown in Table 1.

Example 5 The production of the CB) catalyst component in (2) of Example 1 was carried out in the same manner as in Example 1, except that inbutylalumoxane was used instead of trimethylaluminum. The results are shown in Table 1.

Example 6 (2) Bottom of solid catalyst component 4 mL (4 ssol) of trimethylalum and mL (16 mmol) of methylalumoxane synthesized in (1) of Example 1 were added to a 50 mL flask that had been sufficiently purged with nitrogen. 80℃ under additional nitrogen stream
The mixture was mixed for 2 hours. The entire amount of this reaction mixture was added to 1 g of silica (Fuji Davison grade 952, calcined at 300°C for 4 hours) suspended in 10 mL of toluene, and the mixture was further reacted for 2 hours at 0°C under a nitrogen stream. After the reaction was completed, the solid was separated by the decane silane method, thoroughly washed with toluene, and made into a toluene slurry, which was used as a solid catalyst component (B-6).A part of this was collected and analyzed. The AI content per gram of solid catalyst component was 4.5 msol.

(3) Polymerization of propylene Polymerization was carried out in the same manner as in Example 1, except that (B-6) synthesized in (2) was used as the solid catalyst component. The results are shown in Table 1.

Example 7 Polymerization was carried out in the same manner as in Example 1, except that ethylenebis(indenyl)hafnium dichloride was used as the metallocene catalyst component. Results first
Shown in the table.

Comparative Example 1 Polymerization was carried out in the same manner as in Example 1, except that methylalumoxane corresponding to 0.67 ξ mol in terms of aluminum atoms was used in place of the solid catalyst component (B-1). I did this. The results are shown in Table 1. In this case, the polymer was firmly attached to the inner wall of the autoclave and the stirrer.

Comparative Example 2 Polymerization was carried out in the same manner as in Comparative Example 1, except that ethylenebis(indenyl)hafnium dichloride was used as the metallocene catalyst component. Results first
It is shown in the table. In this case, the polymer was firmly attached to the inner wall of the autoclave and the stirrer.

Example 8 Polymerization was carried out in the same manner as in Example 1, except that methylenebis(cyclopentangenyl)titanium dichloride was used as the metallocene catalyst component. The results are shown in Table 1.

Example 9 Polymerization was carried out in the same manner as in Example 1, except that propylene bis(cyclopentagenyl) titanium dichloride was used as the metallocene catalyst component. The results are shown in Table 1.

Example 1O Polymerization was carried out in the same manner as in Example 1, except that tetramethylenebis(cyclopentagenyl)titanium dichloride was used as the metallocene catalyst component. The results are shown in Table 1.

Example 11 Polymerization was carried out in the same manner as in Example 1, except that ethylene bis(indenyl) zirco-mu 1,1'-bi 2 naphthlate was used as the metallocene catalyst component. The results are shown in Table 1.

Example 12 Example 1 except that ethylenebis(indenyl)zirconium-4,4'-dimethyl-6,6'-di-t-butyl-2,2'-thioferrate was used as the metallocene catalyst component. , Polymerization was carried out in the same manner as in Example 1. The results are shown in Table 1.

Example 13 Polymerization was carried out using the same ingredients as in Example 1 except that ethylenebis(indenyl)propoxyzirconium chloride was used as the metallocene catalyst component.
The results are shown in Table 1.

Example 14 Polymerization was carried out in the same manner as in Example 1, except that ethylenebis(indenyl)butoxyzirconium chloride was used as the metallocene catalyst component. The results are shown in Table 1.

Table 1 [Effects of the invention] When propylene is polymerized by the method of the present invention,
Highly active, highly stereoregular polypropylene with good particle properties and high bulk density can be obtained without causing the problem of polymer adhesion to anti-historical vessels, even when using less alumoxane than in conventional methods. .

Claims (1)

[Claims] 1. (A) General formula ▲ Numerical formula, chemical formula, table, etc. ▼ (R^1 in the formula is a hydrocarbon group having 1 to 20 carbon atoms, and two R^1 When present in adjacent positions of the cyclopentadienyl ring, they may be combined to form a carbocyclic ring, and R^2 is a hydrocarbon group or a thioaryl group, and when two of these exist, The carbon atoms therein may be bonded to each other directly or via a sulfur atom, M is titanium, zirconium, or hafnium, X is a hydrocarbon group or a halogen atom, and n is 1 to
4, m is an integer of 0 or 1 to 4, and l is an integer of 0 or 1 or 2); A method for producing highly stereoregular polypropylene, characterized in that it is used.