JPH0713101B2 - Method for producing propylene polymer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a propylene polymer.

According to the method of the present invention, a propylene polymer having extremely high stereoregularity and excellent polymer properties can be produced under industrially sufficiently high activity.

BACKGROUND ART In recent years, a catalyst system having improved stereoregularity has been proposed by utilizing a magnesium halide or titanium compound containing a specific carboxylic acid ester as a solid catalyst component (Japanese Patent Publication No. 52- No. 36786, 52-369
No. 13, 52-50037, JP-A-56-811 and the like).

However, according to these proposals, in order to obtain a polymer having an industrially acceptable stereoregularity, not only a solid catalyst component but also an electron donor, particularly a specific carboxylic acid ester, is used as a polymerization additive. It usually needed to be used. As a result, the obtained polymer had a major problem of odor due to the catalyst residue derived from the solid catalyst component and the electron donor component used during the polymerization.

It is difficult to eliminate such a cause of odor of the polymer by post-treatment, and it is disadvantageous in production.

Further, in the polymerization of α-olefin having 3 or more carbon atoms,
Without using carboxylic acid ester as a polymerization additive, Si-
Proposals for using an organosilicon compound component having an O—C bond have been proposed such as JP-A-57-63310 and JP-A-57-63311, but both use a specific organic acid ester as a solid catalyst component. However, the above-mentioned technical problems have not been solved.

Further, in the polymerization of α-olefin having 3 or more carbon atoms, a solid catalyst component containing no electron donor such as carboxylic acid ester, an organoaluminum compound component, and an organosilicon compound component having a Si—O—C bond as a polymerization additive. An example using is proposed in JP-A-57-63312, etc., but from the viewpoint of stereoregularity, activity and polymer properties, any of them is significantly inferior to the above-mentioned proposed technique and industrially accepted. Polymers having tremendous stereoregularity, activity and polymer properties have not been obtained, and technical improvements have been desired.

Further, magnesium halide, a catalyst system comprising a solid catalyst component further containing a specific carboxylic acid ester in a titanium compound and an organoaluminum compound, the most suitable polymerization temperature for the polymerization of propylene, about 60 ~ about 70 ℃. When polymerizing at a temperature, one-stage polymerization is performed at an optimum temperature of 60 to 70 ° C, and low-temperature polymerization is performed at the first stage.
It is known that the latter polymerization method improves the activity, stereoregularity, and bulk density of the polymer in the two-stage polymerization in which the second stage is carried out at 60 to 70 ° C (Japanese Patent Publication No. 57-45244). Issue).

However, the above-mentioned two-step polymerization method is industrially disadvantageous in that the productivity is reduced in the batch system, and even in the continuous system, it is disadvantageous because the apparatus and the operation are complicated, and a technical solution is desired.

Further, a method has been proposed in which a solid catalyst component containing titanium, magnesium and halogen as essential components is modified with an organoaluminum compound and olefin so that a small amount of olefin is polymerized (JP-A-56-136806). ). However, the proposal is believed to have disclosed a technique of storing a solid catalyst component containing an aromatic carboxylic acid ester in a dry state, using a solid catalyst component containing no electron donor such as a carboxylic acid ester, There is no description or suggestion of a method for obtaining a highly stereoregular polymer in a high yield.

In addition, a titanium composite containing titanium, magnesium, halogen and an electron donor as essential components is added to Si-O-
A method of reacting with an organic silicon compound having a C bond and an organic aluminum compound to form a solid catalyst component has been proposed (JP-A-58-138715), but titanium which does not contain carboxylic acid esters is also proposed. There is no description or suggestion of a method for obtaining a highly stereoregular polymer in a high yield using the complex.

SUMMARY OF THE INVENTION The present invention is a method for producing a propylene polymer by homopolymerizing or copolymerizing propylene in the presence of a catalyst, wherein the catalyst used is component (I): magnesium dihalide, titanium tetraalkoxide and halogen of silicon. The titanium complex (A), which is a contact product with the compound, the organoaluminum compound (B), and propylene (C) are at 50 ° C. or less, and the concentration of the organoaluminum compound (B) is 0.05 to 0.5 mol / liter. Solid catalyst component formed by contacting with propylene and the reaction is carried out until propylene becomes 0.1 to 100 g per 1 g of the titanium composite (A), component (II): organoaluminum compound, and component (III): an organosilicon compound having a Si-O-C bond, and the polymerization is carried out at a concentration of the organoaluminum compound (II). 0.0005-0.02 preparation of the propylene polymer is intended to be performed under the conditions of the range of mol / liters and provides a.

EFFECTS OF THE INVENTION According to the method of the present invention, a propylene polymer having an extremely high stereoregularity and a large bulk density of the produced polymer, which is an excellent polymer property, has high catalytic activity and produces little polymer soluble in a polymerization solvent. A method for producing a propylene polymer which is industrially extremely advantageous is provided.

Further, since no electron donor such as carboxylic acid ester is used as the catalyst forming component, the odor of the product polymer is remarkably improved.

When propylene is polymerized or copolymerized with propylene and ethylene or butene by the method of the present invention, the first stage polymerization is performed at a temperature lower than the optimum temperature condition before the polymerization at about 60 to 80 ° C which is the optimum temperature condition. And then about 60 ~
A two-stage polymerization method in which the polymerization is performed under the optimum temperature condition of 80 ° C.
A polymer having high activity, high stereoregularity and good polymer properties can be obtained by single-step polymerization without employing an industrially disadvantageous polymerization method.

Furthermore, according to the method of the present invention, a polymer having an extremely high stereoregularity can be obtained in a high yield, and the production of a polymer soluble in a polymerization solvent is extremely small. Therefore, the detouching step and the extraction step of the attack polymer are omitted. Despite the fact that the polymer obtained is 0.9030 g / cc to 0.9055 g / cc (MFR
= (Value corrected to 2), which is a polymer that does not reduce the impact resistance of the molded product and the effect of adding an antistatic agent to the film.

DETAILED DESCRIPTION OF THE INVENTION [Catalyst] The catalyst used in the present invention is formed from the component (I), the component (II) and the component (III).

Component (I): Solid catalyst component (I) used in the present invention
Is formed by catalytically reacting the component (A), the component (B) and the component (C) under specific conditions.

Component (A) is a titanium complex that is a contact product of magnesium dihalide, titanium tetraalkoxide and a halogen compound of silicon.

Specific examples of the magnesium dihalide (component (i)) used in the present invention include MgCl ₂ , MgBr ₂ , MgF _{2 and the} like. Further, titanium tetraalkoxide is a compound represented by the general formula Ti (OR) ₄ (R represents a hydrocarbon residue). _{Specifically, Ti (O-C 2 H} 5) 4, Ti (O-
_{isoC 3 H 7) 4, Ti} (O-nC 3 H 9) 4, Ti (O-nC
_{3 H 7) 4, Ti (} O-isoC 4 H 9) 4, Ti _{[O-CH 2 CH (CH 3} )
_{2] 4,} Ti [O-C (CH _{3) 3] 4, Ti (O-C 5} H
_{n) 4, Ti (O-} C 6 H 13) 4, Ti (O-C 7 H 15) 4, Ti
_{(O-C 8 H 17)} 4, Ti (O-C 10 H 21) tetraalkoxy titanium compounds such as ₄ can be exemplified.

And, a halogen compound of silicon (as the component (iii), a compound represented by the general formula ▲ R ¹ _n ▼ SiX _4- n (R ² represents a hydrocarbon residue and X represents a halogen atom, respectively) is preferable. Is n = 0, 1 or 2. Specifically, SiCl ₄ , SiBr ₄ , CH ₃ SiCl ₃ , C ₂ H ₅ SiCl ₃ , C ₆ H ₁₃ SiCl.
₃ , C ₆ H ₅ SiCl ₃ , CH ₃ C ₆ H ₄ SiCl ₃ , C ₂ H ₃ SiCl ₃ , (C ₂ H ₅ ) ₂ Si
Cl ₂ , (C ₆ H ₅ ) ₂ SiCl ₂ , and so on. Of course, two or more kinds of these halogen compounds of silicon may be used in combination.

Each of the above components (i) of the titanium composite that is the component (A),
The amounts of (ii) and (iii) used are arbitrary as long as the effects of the present invention are observed, but generally, the following ranges are preferable. That is, the amount of titanium tetraalkoxide used is about 0 in a molar ratio to magnesium dihalide.
It is within the range of 01 to about 100, more preferably about 0.1 to about 50, particularly preferably about 1 to about 10. The amount of the halogen compound of silicon used is in the range of about 0.1 to about 10, particularly preferably about 1 to about 5 in molar ratio with respect to the titanium tetraalkoxide.

The method of contacting the above-mentioned components (i), (ii) and (iii) is to contact the components (i) to (iii) all at once or stepwise or once or a plurality of times, and various methods are available. It can be obtained by a preparation method. Some of the specific preparation methods are shown below.

Ingredient (i) magnesium dihalide and ingredient (i
i) is mixed and ground, and the obtained ground product is brought into contact with the component (iii) in a liquid phase.

Component (ii) is further contacted in the liquid phase with the contact product obtained in (1).

Component (i) is contacted with component (ii) in the liquid phase and then component (iii) is contacted in the liquid phase.

Component (i) is contacted with component (ii) in a liquid phase to prepare a hydrocarbon solution containing component (i), and this solution is contacted with component (iii) or a halogenating agent such as titanium halide. A solid is deposited and the deposited solid and the component (ii
i) and component (ii) are contacted in the liquid phase either sequentially or simultaneously.

Component (i) is catalytically reacted with component (ii), dissolved in a hydrocarbon solvent, and then The reaction is made with a polymer silicon compound having a structure shown in to precipitate a solid, and the solid composition containing the component (i) and the halogen compound of the component (iii) silicon are brought into contact with each other.

The component (ii) and the component (iii) are brought into contact with the solid catalyst component obtained in step 1.

The precipitated solid composition obtained in step 1 is brought into contact with the halogen compound of titanium, and then the component (ii) and the component (iii) are brought into contact with each other.

The precipitated solid composition obtained in (1) and the halogen compound of titanium and silicon are brought into contact with each other, and then the components (ii) and (iii) are brought into contact with each other.

The contact may be performed in the presence of a dispersion medium. Examples of the dispersion medium in that case include hydrocarbons and halogenated hydrocarbons. Specific examples of hydrocarbons include:
There are hexane, heptane, toluene, cyclohexane and the like, and specific examples of the halogenated hydrocarbon include n-butyl chloride, 1,2-dichloroethylene, carbon tetrachloride, chlorobenzene and the like.

In addition, a halogenating agent such as a halogen compound of component (iii) and a halogen compound of titanium or aluminum may be used in combination.

Particularly preferable methods for preparing the titanium composite (A) are (6) and (6) among the above-mentioned preparation methods.

Component (B) is an organic aminium compound. The organic aluminum compound (B) has the general formula ^{_{Al ▲ R 3 n ▼ X 3-}} n (R 3
Is a hydrocarbon residue, X is a halogen or alkoxy group,
n is a compound represented by 0 <n ≦ 3), a preferable compound is n = 2 or 3, and a particularly preferable compound is n = 3. Specifically, triethyl aluminum, tri-n-propyl aluminum, tri-
n-Butyl aluminum, tri-iso-butyl aluminum, tri-n-hexyl aluminum, tri-iso-
Examples include hexyl aluminum and trioctyl aluminum.

Component (C) is propylene.

The above-mentioned component (A), component (B) and component (C) are catalytically reacted to obtain a solid catalyst component (I). in this case,
The component (B) is preferably used so that the ratio of Al atoms of the organoaluminum compound to the Ti atoms of the titanium composite (A), the Al / Ti molar ratio is 1 to 100, preferably 4 to 20. Further, the component (B) has a concentration of 0.05 to 0.5 mol / liter with respect to a liquid component including a solvent used for the catalytic reaction of the component (A), the component (B) and the component (C), particularly preferably.
0.1 to 0.3 mol / liter is preferable, and at a concentration lower than 0.05 mol / liter, the effect of the present invention is not obtained, especially in a single-stage polymerization of about 60 to 80 ° C.
Not only the stereoregularity decreases and the amount of polymerized soluble polymer increases, but also the bulk density of the polymer decreases. Further, at a concentration exceeding 0.5 mol / liter, the polymerization activity remarkably decreases.

The propylene as the component (C) is polymerized in an amount of 0.1 g or more per 1 g of the component (A), usually 0.1 to 100 g, particularly preferably 1 to 30 g. This polymerization amount is the solid catalyst component (I) produced.
In the operation of homopolymerization or copolymerization of propylene,
It is advantageous to reduce the amount of polymerization so that the volume of component (I) is small.

In the formation of component (I), hydrogen and / or Si-O
It is also possible to use an organosilicon compound having a -C bond. Hydrogen has a gas phase concentration of about 1 to about 50%, preferably about 5 to 5.
Choose a concentration of about 20%. The amount of the organosilicon compound is about 1 mol or less, preferably about 0.01 to 1 atom of aluminum of the organoaluminum compound of the component (B).
It is preferable to use it in the range of about 0.5 mol. The organosilicon compound is preferably used in an amount of about 0.01 to about 5, preferably about 0.05 to about 2 mol, based on 1 atom of titanium in the titanium composite of component (A).

Here, the organosilicon compound having a Si—O—C bond is
Compounds having at least one Si-O-C bond, such as alkoxysilanes and aryloxysilanes.
Other examples include siloxanes having an alkoxy group, silyl esters of carboxylic acids, and the like.

More specifically, the following compounds can be exemplified. Trimethylmethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, te
rt-Butylmethyldimethoxysilane, tert-butylmethyldiethoxysilane, 2-norbornanemethyldimethoxysilane, 2-norbornanemethyltriethoxysilane, diphenyldimethoxysilane, methylphenyldimethoxysilane, diphenyldiethoxysilane, ethyltrimethoxy Silane, vinyltrimethoxysilane, methyltrimethoxysilane, phenyltrimethoxysilane, methyltariethoxysilane, ethyltriethoxysilane,
Vinyltriethoxysilane, n-butyltriethoxysilane, tert-butyltriethoxysilane, phenyltriethoxysilane, chlorotriethoxysilane, 2-norbornanetriethoxysilane, 2-norbornenetriethoxysilane, 5-ethylidene-2- Examples thereof include norbornanetriethoxysilane, 5-ethylidene-2-norbornanetrimethoxysilane, and tetraethoxysilane.

Of these, particularly preferred are phenyltrimethoxysilane, phenyltriethoxysilane, 2-norbornanetriethoxysilane, 2-norbornenetriethoxysilane, 5-ethylidene-2-norbornanetriethoxysilane, 5-ethylidene-2. -Norbornanetrimethoxysilane, tert-butyltrimethoxysilane, tert-
Such as butyltriethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, 2-norbornanemethyldimethoxysilane, 2-norbornanemethyldiethoxysilane, tert-butylmethyldimethoxysilane, tert-butylmethyldiethoxysilane, etc. Organosilicon compounds having 2 to 3 alkoxy groups are particularly preferred.

The catalytic reaction of the above-mentioned component (A), component (B) and component (C) may be carried out in any order, and the catalytic reaction may be carried out once or plural times. Various contact methods can be used.

Further, this catalytic reaction is carried out in the liquid phase or the gas phase in the presence or absence of an inert diluent such as hexane or heptane. When contacting in the liquid phase, the concentration of the titanium composite (A) is about 1 to about 100 g / liter, preferably about 5 to about 50 g / liter.
Just choose to be a littor. In this contact reaction, an inert gas such as nitrogen or argon can be used together with propylene as the component (C).

The temperature of this contact reaction may be any number of times as long as it is 50 ° C. or lower, preferably about 30 ° C. or lower, but it is not preferable to lower the temperature too much from the viewpoint of removing the heat of polymerization and the reaction rate. Is preferably carried out in the range of about 0 to about 30 ° C.

When an organosilicon compound having a Si—O—C bond is used in the formation of component (I), the organosilicon compound is any stage of the catalytic reaction of component (A), component (B) and component (C). May be used in. Also, a product obtained by contacting an organosilicon compound and a titanium composite (A), or a solid product and a component (B) obtained by separating and washing after the contact.
And the component (C) may be contacted.

Furthermore, when hydrogen is used in the formation of component (I), hydrogen may be added at any stage of contacting component (4), component (B) and component (C) and optionally the organosilicon compound. It is necessary that at least the component (C) is present at the stage of the catalytic reaction.

The solid contact component (I) obtained using an organosilicon compound or hydrogen is formed by combining the organoaluminum compound of component (II) and the organosilicon compound having a Si—O—C bond of component (III). When the catalyst is used for the polymerization of propylene, the activity, stereoregularity and polymer properties are further improved.

The solid catalyst component formed by contacting component (A), component (B) and component (C) as described above, or further contacting hydrogen and / or an organosilicon compound is separated from the reaction product system. , For example
Further, the obtained solid catalyst component can be washed with an inert organic solvent, preferably an inert hydrocarbon solvent to obtain the solid catalyst component (I) in the present invention.

Component (II): The organoaluminum compound catalyst component (II) used in the present invention is represented by the general formula Al ▲ R ⁴ _n ▼ X _3- n (R ⁴ is a hydrocarbon residue having 1 to 12 carbon atoms, and X is Halogen atom, n is a compound represented by 0 <n ≦ 3).

Specific examples of such an organoaluminum compound include triethylaluminum, tri-n-propylaluminum, tri-n-butylaluminum, and tri-aluminum.
Examples include iso-butyl aluminum, tri-n-hexyl aluminum, tri-iso-hexyl aluminum, trioctyl aluminum, diethyl aluminum hydride, diisobutyl aluminum hydride, diethyl aluminum monochloride, ethyl aluminum sesquichloride. Of course, two or more of these organoaluminum compounds can be used in combination.

The organoaluminum compound (II) used in homopolymerization or copolymerization of propylene is preferably used in a concentration of 0.0005 to 0.02 mol / liter, particularly preferably 0.0005 to 0.01 mol / liter with respect to the liquid component used in this polymerization. Is. At a concentration higher than 0.02 mol / liter, the effect of the present invention is small, resulting in a decrease in the activity and an increase in the polymer soluble in the polymerization solvent as compared with the case where the preferred range of use is carried out.

The ratio of the component (II) to the solid catalyst component (I) used can be varied over a wide range, but generally 1 to 1,000, preferably 10 to 500 (mole) per titanium atom contained in the solid catalyst component (I). The ratio can be selected.

Component (III): The organosilicon compound catalyst component (III) used in the present invention can be selected from those exemplified as the organosilicon compound that can be used for the synthesis of the solid catalyst component (I). As a preferable organic silicon compound, the organic silicon compound having 2 to 3 alkoxy groups exemplified above is used.

The amount of the organosilicon compound (III) having a Si—O—C bond used is usually the organoaluminum compound (II) 1
It is used in a ratio of 0.001 to 1 mol, preferably 0.01 to 0.5 mol, based on mol.

Solid catalyst component (I), organoaluminum compound (II) and organosilicon compound (III) having Si—O—C bond
And the order of mixing and the number of times of mixing are arbitrary.

〔polymerization〕

The polymerization is carried out in the presence of the catalyst formed from the catalyst component (I), the component (II) and the component (III) obtained as described above. It may be carried out under the condition that the concentration of the aluminum compound is in the range of 0.0005 to 0.02 mol / liter.

Polymerization in the method of the present invention can be carried out not only by homopolymerization of propylene but also by random copolymerization of propylene and α-olefins such as ethylene, 1-butene, 1-hexene and 4-methylpentene, and block copolymerization. it can. Regarding copolymerization, polyunsaturated compounds such as conjugated dienes and non-conjugated dienes can also be used as the copolymerization olefin.

As the polymerization method, a so-called slurry polymerization method in which an inert hydrocarbon such as hexane or heptane is used as a solvent, a liquid phase polymerization method in which a liquefied monomer is used as a solvent, or a gas phase polymerization method in which a monomer is present as a gas phase can be used. .

The polymerization temperature is generally about 20 to 150 ° C, preferably 40 to 100 ° C.
The polymerization pressure is about atmospheric pressure to about 100 atmospheres, preferably about atmospheric pressure to about 50 atmospheres. The molecular weight of the polymer is controlled mainly by a method using hydrogen.

Examples Example 1 [Production of Titanium Composite (A)] In a separable flask equipped with 10 induction stirrers sufficiently replaced with nitrogen, dehydrated and deoxygenated n-heptane 1.
5 was introduced, and then MgCl ₂ (magnesium chloride) was added to 3
After introducing 6 mol of Ti (OBu) ₄ (tetrabutoxytitanium), a hydrocarbon solution of MgCl ₂ was prepared by reacting at 90 ° C. for 2 hours. Next, when 360 ml of methylhydrogen polysiloxane (20 cps) was added and reacted at 40 ° C. for 3 hours, about 1.2 kg of an off-white solid was deposited (component (i)). The precipitated solid was thoroughly washed with n-heptane and analyzed, and it was found that the precipitated solid contained 12.1% by weight of MgCl 2.
₂ was included.

From this precipitated solid, 1 Kg was sampled as a 3.25 slurry and placed in the same 10 separable flask as above. Then n-heptane 2.1 is added to this and TiCl ₄
A solution prepared by diluting 135 ml of (titanium tetrachloride) with the same amount of n-heptane was added at about 15 ° C over 30 minutes. At this time, the reaction vessel was stirred and cooled with water. After the completion of this addition, the reaction was allowed to proceed for another 15 minutes, then 145 ml of SiCl ₄ (silicon tetrachloride) was added, the reaction was carried out at about 20 ° C. for 1 hour, and the temperature was further raised to 80 ° C. and the reaction was performed for 2 hours. After the completion of the reaction, the mixture was left standing to precipitate the produced solid, and then the supernatant was extracted.

Then, the reaction vessel was cooled to 20 ° C. and the components (ii
580 ml of SiCl ₄ as i) was added, and 850 ml of Ti (OBu) ₄ as component (ii) was added at 20 ° C. over 30 minutes.
At this time, the reaction tank was stirred and cooled with water. After the addition was completed, the mixture was further reacted at 90 ° C. for 2 hours, 5 n-heptane was added thereto, and the mixture was allowed to stand to precipitate the produced solid, and then the supernatant was extracted.

After this treatment, the solid produced is decanted to about 50 ° C.
(3 times with n-heptane 7.5) to obtain a slurry containing about 240 g of the target titanium composite (A). When a part of this slurry was sampled and n-heptane was evaporated to dryness and analyzed, it was found that the solid contained 5.49% by weight of titanium.

[Production of Solid Catalyst Component (I)]

An autoclave equipped with a stirrer having an internal volume of 1 was sufficiently replaced with nitrogen, and 130 ml of dried and degassed n-heptane was introduced. Then, 180 ml of a heptane slurry containing 20 g of the titanium composite (A) produced as described above was added thereto.
Then, the autoclave was cooled to about 5 ° C., 210 ml of an n-heptane solution containing 10.4 g of triethylaluminum was added (Al = 0.18 mol / liter), 200 ml of hydrogen was introduced, and 80 g of propylene was continuously added over 20 minutes. Was added. The temperature of the reaction was controlled to about 15 ° C. After the introduction of propylene, the reaction was completed for another 20 minutes to obtain an n-heptane slurry containing the target solid catalyst component (I).
This solid catalyst component (I) was diluted to an arbitrary concentration by adding n-heptane and used in the following propylene polymerization.

[Polymerization of propylene]

(A) Polymerization-1 In an autoclave equipped with a stirrer with an internal volume of 1, dried and degassed n-heptane 500 ml, phenyltriethoxysilane 107 mg, triethylaluminum 250 mg (0.00
44 mol / liter) was added and the temperature was raised to 70 ° C. From the solid catalyst component (I) slurry produced as described above, 1.0 mg in terms of Ti atom was introduced under a propylene atmosphere, 100 ml of hydrogen was then added, and the pressure was immediately raised to 7 kg / cm ² G to start polymerization. The polymerization was carried out at a propylene pressure of 7 kg / cm ² G and 70 ° C. for 3 hours. After completion of the polymerization, residual monomers were purged, the polymer slurry was separated, and the amount of each polymer produced was determined by drying the powder polymer and concentrating the liquid.

Stereoregularity of this powder polymer (hereinafter referred to as product II)
Was determined by a boiling heptane extraction test. Also, all II
(Ratio of boiling heptane-insoluble polymer amount to total produced polymer amount) was determined by the relational expression: total II = powder polymer amount × product II / (powder polymer amount + liquid concentrated polymer amount). These results are shown in Table-1.

The density of the obtained powder polymer was obtained by making a press sheet sample and correcting the density to MFR = 2 by the following equation by a density gradient tube measurement method.

Polymer density (MFR = 2 correction value) = [logMFR (measured value) -log2] x 0.0015-Polymer density (measured value) (b) Polymerization-2 Polymerization-2 is a solid catalyst component (I) in Polymerization-1. Polymerization was carried out under the same conditions as in Polymerization-1, except that 0.7 mg of Ti atom was used from the slurry and 72.8 mg of tert-butylmethyldimethoxysilane was used instead of phenyltriethoxysilane.

Examples 2 to 7 In the same production method as in the solid catalyst component (I) of Example 1, the organoaluminum compound (B) used for the contact treatment with the titanium composite (A), the Al / Ti molar ratio and the organoaluminum are used. The compound concentration was changed as shown in Table 1, and the catalyst production and polymerization were carried out in the same manner as in Example 1 without changing the amount of propylene polymerized per titanium complex (A), the amount of hydrogen used, the contact temperature and the time. Carried out. The results of the polymerization are shown in Table-1.

Example 8 In the synthesis of the solid catalyst component (I) of Example 1, hydrogen was not used in the catalytic reaction with the titanium complex (A), the organoaluminum compound (B) and propylene (C). The same catalyst production and polymerization as in Example 1 were carried out. The results are shown in Table-1.

Examples 9 to 12 In the production of the solid catalyst component (I) of Example 1, the amount of triethylaluminum (B) (Al / Ti (molar ratio)) and the concentration of triethylaluminum were used under the conditions shown in Table-2. Then, catalyst production was carried out. However, these catalytic reactions were carried out using phenyltriethoxysilane in an amount ratio shown in Table 2 as an additional component.

Polymerization of propylene was carried out under the same conditions as in Polymerization-1 of Example 1 except that the obtained solid catalyst component (I) was used. The results are shown in Table-2.

Example 13 The same solid catalyst component (I) slurry 10 used in Example 1
0 ml was sampled in a 300 ml flask which had been thoroughly purged with nitrogen, and this was washed with 200 ml of n-heptane three times by decantation, and then n-heptane was added thereto.
100 ml of solid catalyst component (I) slurry was obtained.

The obtained solid catalyst component (I) was stored at room temperature for about 1 month, and then propylene was polymerized in the same manner as Polymerization-1 of Example 1 except that this solid catalyst component (I) was used. . The obtained results are shown in Table 2.

Comparative Example 1 In the production of the solid catalyst component (I) of Example 1, the concentration of triethylaluminum used for the contact treatment with the titanium composite (A) was 0.018 mol / liter, and the titanium composite (A) was used. Example 1 except that the amount was changed to 2 g
A catalyst was produced in the same manner as in. Polymerization of propylene was carried out in the same manner as in Polymerization-1 of Example 1 except that the catalyst thus obtained was used. The results are shown in Table-3.

Comparative Example 2 The titanium composite (A) produced in Example 1 was converted into Ti atoms.
Polymerization of propylene was carried out in exactly the same manner as Polymerization-1 of Example 1 except that 0.7 mg was used and this was used instead of the solid catalyst component (I) used in Polymerization-1 of Example 1. The results are shown in Table-3.

Comparative Example 3 In Polymerization-1 of Example 1, 1.0 mg of the titanium composite (A) produced in Example 1 was used in place of the solid catalyst component (I) in terms of Ti atom, and this was used at 20 ° C. in a propylene atmosphere. Then, 100 ml of hydrogen was added, and polymerization was carried out at 20 ° C. and a propylene pressure of 1 kg / cm ² G for 0.5 hour, and then the temperature was immediately raised to 70
The temperature was raised to 0 ° C., and then propylene was polymerized at a propylene pressure of 7 kg / cm ² G for 3 hours. The results are shown in Table-3.

Comparative Example 4 Polymerization of propylene in exactly the same manner as Polymerization-1 of Example 1 except that 2 g (0.035 mol / liter) of triethylaluminum and 0.84 g of phenyltriethoxysilane were used in Polymerization-1 of Example 1. I went. The results are shown in Table-3.

From the above Examples and Comparative Examples, the contact conditions of the titanium composite (A) with the organoaluminum compound (B) and propylene (C) and the concentration of the organoaluminum compound at the time of polymerization are very important for constituting the present invention. It is clear that this is important.

[Brief description of drawings]

FIG. 1 is intended to help the understanding of the technical content of the present invention regarding the Ziegler catalyst.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshihiko Sugano 1 Toho-cho, Yokkaichi-shi, Mie Prefectural Resin Research Laboratory, Mitsubishi Petrochemical Co., Ltd. (56) Reference JP-A-59-219311 (JP, A)

Claims (1)

[Claims] 1. A method for producing a propylene polymer by homopolymerizing or copolymerizing propylene in the presence of a catalyst, wherein the catalyst used is component (I): magnesium dihalide, titanium tetraalkoxide and a halogen compound of silicon. The titanium composite (A), which is a contact product of the above, and the organoaluminum compound (B) and propylene (C) are contacted at 50 ° C. or less at a concentration of the organoaluminum compound (B) of 0.05 to 0.5 mol / liter. A solid catalyst component formed by reacting and performing this reaction until 0.1 to 100 g of propylene per 1 g of the titanium composite (A), component (II): organoaluminum compound, and component (III ): An organosilicon compound having a Si—O—C bond, and the polymerization is carried out at a concentration of the organoaluminum compound (II) of 0.0005 to 0. A method for producing a propylene polymer, which is carried out under the condition of 02 mol / liter.