JPH0653776B2 - Process for producing ethylene-olefin copolymer - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing an ethylene copolymer by copolymerizing ethylene and an olefin having 3 or more carbon atoms under gas phase polymerization conditions.

As is conventionally known, when ethylene and an olefin are copolymerized, the polymer density of the resulting copolymer is lower than that of the homopolymer. The method of producing a copolymer of ethylene and olefin is roughly classified into two types. That is, one is so-called "solution polymerization" (generally high temperature) which is carried out by dissolving the produced polymer in a solvent such as hydrocarbon. The other one is so-called "slurry polymerization" or "gas phase polymerization", in which the polymerization is carried out substantially with the formation of polymer particles.

The "gas phase polymerization" in the latter polymerization method is an excellent method for producing a copolymer, since no solvent is used. However, "gas phase polymerization" has problems such as polymer adhesion, lump polymer formation, and low melting point low molecular weight polymer generation. For these problems,
Proposals to improve this have been made, but it cannot be said that they have been sufficiently improved.

Prior Art Examples of prior art include JP-A-55-52309, JP-A-55-54308, JP-A-55-58210, and JP-A-58-122904.

Although these prior arts have some improvement effects on the above-mentioned problems, they are still insufficient in practical use.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a solution to the above points, and a supported transition metal catalyst component (component (A ₁ )) and an organoaluminum compound (component (A ₂ )) prepared in a specific embodiment.
The present invention is intended to achieve the above object by a catalyst system consisting of a specific polar compound (component (A ₃ )).

Therefore, in the method for producing an ethylene-olefin copolymer according to the present invention, ethylene and an olefin having 3 or more carbon atoms are subjected to gas phase polymerization conditions in a catalyst system comprising a combination of the following components (A ₁ ) to (A ₃ ). Under contact, polymer density 0.9
It is characterized in that an ethylene-olefin copolymer in the range of 00 to 0.945 g / cm ³ is obtained.

Component (A ₁ ) A contact product of (a) magnesium dihalide with (b) a compound selected from tetraalkoxytitanium and tetraalkoxysilane is contacted with (c) an alcohol compound, and then (d) TiX ₄ (wherein , X represents a halogen), and the average particle size is 10
Those in the range of micron to 100 micron.

Component (A ₂ ) An organoaluminum compound.

Component (A ₃₎ the following formula _{(A 3 -1), (A} 3 -2) and (A ₃ -3) is selected from a compound having a CO-R bond.

(A ₃ −1) R ¹ C (OR ² ) ₃ (wherein R ¹ and R ² are each 1 to 12 carbon atoms.
Is a hydrocarbon residue of. The three R ² may be the same or different. At least two members of R ¹ and R ² may be linked to each other to form a ring. ^{_{) (A 3 -2) R 3}} R 4 C (OR 5) 2 ( wherein, R ³ and R ^4, carbon atoms respectively 1-12
Is a hydrocarbon residue of R ⁴ , and R ⁴ is hydrogen or a carbon number of 1 to 1.
2 hydrocarbon residue. Two R ^5's may be the same or different. At least two members of R ³ , R ⁴ and R ⁵ may be linked to each other to form a ring. ^{_{) (A 3 -3) R 6}} R 7 R 8 C (OR 9) ( wherein, R ⁶ and R ^9, carbon atoms respectively 1-12
R ⁷ and R ⁸ are each hydrogen or a hydrocarbon residue having 1 to 12 carbon atoms. R ⁶ ,
At least two of R ⁷ , R ⁸ and R ⁹ may be linked to each other to form a ring. ) Effect In the present invention, it is possible to provide a solution to various points which are problems in “gas phase polymerization” in producing an ethylene-olefin copolymer. That is, polymer adhesion,
Generation of bulk polymer, low melting point low molecular weight polymer, etc. is prevented. Preventing polymer adhesion and generation of lumpy polymer is extremely polymerization in terms of stable operation. In addition, the low melting point and low molecular weight polymer adversely affects the quality of the polymer produced. For example, it may cause stickiness in the film and decrease in strength.

The cause of producing such an effect is not clear at present, but it is considered to be due to the interaction of the components (A ₁ ) to (A ₃ ) constituting the present invention.

DETAILED DESCRIPTION component of the invention (A ₁₎ / composition ingredients according to the invention (A ₁₎ is made of a contact product of the following components.

(A) Magnesium dihalide For example, MgF ₂ , MgCl ₂ , MgBr ₂ and M
gI ₂ and the like.

(B) a compound selected from tetraalkoxy titanium and tetraalkoxy silane _{example, Si (O-nC 4 H} 9) 4, Ti (OC 2 H 5) 4, Ti (O iC 3 H 7) 4 and Ti (O- nC ₄ H ₉ ) ₄ and the like.

(C) Alcohol Compounds One group of alcohols to be used in the present invention is alkanols.

Monohydric alcohols or polyhydric alcohols having about 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms are generally suitable, and specifically, for example, methanol, ethanol, isopropanol, n-propanol, isobutanol, n.
-Butanol, hexanol, n-octanol, 2-
Examples thereof include ethylhexanol, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoacetate and glycerin.

Another group of alcohols to be used in the present invention is silanols.

A silanol having about 1 to 20 carbon atoms is generally suitable, and specific examples thereof include trimethylsilanol, dimethylsilanediol, diphenylsilanediol, and phenylsilanetriol.

Yet another group of alcohols to be used in the present invention are phenols such as phenol, ortho-cresol, para-cresol.

(D) Compound Represented by TiX ₄ (where X represents Halogen) Specific examples include TiCl ₄ and TiBr ₄ .

Further, the above TiX ₄ (where X represents halogen)
The following polymer silicon compound (e) can be used in combination with the compound represented by

That is, this is Is a polymer silicon compound having a structure shown by (R ¹ has about 1 to 10 carbon atoms), and specific examples include methylhydropolysiloxane, ethylhydropolysiloxane, phenylhydropolysiloxane, cyclohexylhydro. Examples include polysiloxane. The degree of polymerization of these polymeric silicon compounds is not particularly limited, but from the viewpoint of handling, it is preferably about 10 centistokes to 100 centistokes. Although the terminal structure of these hydropolysiloxanes does not have a great influence on the catalyst component of the present invention, it is desirable that they be blocked with an inert group such as a trialkylsilyl group. Among these polymeric silicon compounds, alkyl hydrosiloxanes,
Methyl hydrosiloxane is particularly preferable.

Ingredient (A ₁ ) / Production Ingredient (A ₁ ) according to the present invention is prepared by contacting the above ingredients in a specific order or manner.

The amount of each component used may be any amount as long as the effects of the present invention can be recognized, but in general, it is preferably within the following range.

The amount of the compound selected from tetraalkoxytitanium and tetraalkoxysilane used is preferably in the range of 1 × 10 ⁻³ to 50, and more preferably in the range of 0.1 to 10 in terms of molar ratio to magnesium dihalide. is there.

The amount of alcohol used is preferably in the range of 1 × 10 ⁻⁴ to 1 in terms of molar ratio to magnesium dihalide, and more preferably in the range of 0.1 to 0.8.

The amount of the compound represented by TiX ₄ (where X represents halogen) used is preferably in the range of 1 × 10 ⁻³ to 50 in terms of molar ratio with respect to the magnesium dihalide. When used in combination with a polymeric silicon compound, 5 × 10 ^-2 to 4 × 1
The range of 0 ^-1 is preferable. The polymer silicon compound is used in a molar ratio of 1 × to magnesium dihalide.
It is preferably in the range of 10 ⁻³ to 50, and more preferably 0.1.
Within the range of

(A)-(d) Contact of Each Component Contact of each component may be arbitrary, as long as the contact of the alcohol compound is desirably performed in a specific mode, and as long as the effects of the present invention are observed. The contact temperature may be in the range of -50 ° C to 200 ° C.

The contact between the magnesium dihalide (a) and the compound (b) selected from tetraalkoxytitanium and tetraalkoxysilane is carried out by bringing the surface of the magnesium dihalide particles into contact with an alkoxide compound. It is carried out by stirring the liquid alkoxide compound or alkoxide particles together with the liquid alkoxide compound or the solution of the alkoxide compound. It is also possible to make the contact of each component more complete by mechanically pulverizing with a ball mill, a vibration mill, or the like.

The contact of each component can also be performed in the presence of a dispersion medium. Examples of the dispersion medium in that case include hydrocarbons, halogenated hydrocarbons, dialkyl siloxanes and the like. Specific examples of hydrocarbons include hexane, heptane, toluene,
Cyclohexane, etc., and specific examples of the halogenated hydrocarbon include n-butyl chloride, 1,2 dichloroethylene, carbon tetrachloride, chlorobenzene, etc., and specific examples of the dialkyl polysiloxane include dimethyl polysiloxane, Methyl-phenyl polysiloxane and the like.

The contact product of the compound (b) selected from magnesium dihalide (a) with tetraalkoxytitanium and tetraalkoxysilane and the alcohol (c) are contacted with magnesium dihalide (a) and the alkoxide compound (b). It is desirable that the alcohol compound is brought into contact with only the surface portion of the object. Therefore, the method of immersing the (a)-(b) contact product particles in the alcohol compound bath is not preferable except that the alcohol compound (c) does not penetrate to the center of the particle in a short time.

A preferred method comprises spraying the alcohol in the form of droplets of 10 to 1000 microns onto the contact product particles of the magnesium dihalide and the alkoxide compound or the contact product particle suspension and depositing them on the surface of the particles. At this time, the alcohol is preferably such that the particles of the contact product of the magnesium dihalide and the alkoxide compound are moistened, and the state of immersing the particles in an excess alcohol liquid is preferably avoided. The contact time is preferably relatively short, and may be about 1 second to 5 minutes. The solid particles thus obtained are unit particles ((a)-
(B) Reactant is a porous structure (average particle size: 10 to 100 microns) bonded on its surface.

Solid particles obtained as described above and a compound (d) represented by TiX ₄ (where X represents halogen)
(And optionally contact with the polymeric silicon compound (e)) can be carried out as described above for contacting the compound (a) with the compound (b).

Component (A ₂ ) Specific examples of the organoaluminum compound of component (A ₂ ) include the general formula: ▲ R ² _3-n ▼ AlX _n or ▲ R ³ _3-m ▼ Al (O
R) _m (wherein R ² and R ³ may be the same or different and are a hydrocarbon residue or hydrogen having about 1 to 20 carbon atoms, R ⁴ is a hydrocarbon residue, X is halogen, n and m are 0 ≦
The numbers are n <3 and 0 <m <3. ). Specifically, (a) trialkylaluminum such as trimethylaluminum, triethylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, and tridecylaluminum, (b) diethyl-aluminum monochloride, diisobutylaluminum monochloride, ethyl. Alkyl aluminum halides such as aluminum sesquichloride, ethyl aluminum dichloride, (c) Diethyl aluminum hydride, diacyl aluminum hydride such as diisobutyl aluminum hydride, (d) Diethyl aluminum ethoxide, diethyl aluminum butoxide, alkyl aluminum alkoxide such as diethyl aluminum phenoxide And so on.

In addition to these organoaluminum compounds (a) to (c), other organometallic compounds such as ▲ R ⁵ _3-a ▼ Al (OR) _a (1≤a≤3, R ⁵ and R ⁶ are the same or different. It is also a hydrocarbon residue having about 1 to 20 carbon atoms). For example, combined use of triethylaluminum and diethylaluminum ethoxide, combined use of diethylaluminum monochloride and diethyl-aluminum ethoxide, combined use of ethylaluminum dichloride and ethylaluminum diethoxide, triethylaluminum, diethylaluminum ethoxide and diethylaluminum. It can be used in combination with chloride.

The amount of these organometallic compounds used is not particularly limited, but is preferably within a range of 0.5 to 1000 in weight ratio with respect to the solid catalyst component (A ₁ ) of the present invention.

Component (A ₃₎ a compound having a C-OR bond the effects in the present invention can reveal are those selected from the compounds represented by the following formula.

(1) R ¹ C (OR ² ) ₃ (wherein R ¹ and R ² are each a carbon number of 1 to 12).
Is a hydrocarbon residue of. The three R ² may be the same or different. At least two members of R ¹ and R ² may be linked to each other to form a ring. ) This compound is generally called an orthocarboxylic acid ester, and the following can be exemplified.

That is, it is methyl orthoacetate, ethyl orthoacetate, ethyl orthopropionate, ethyl orthobenzoate and the like. Among these, those having a phenyl group at the α-position, that is, methyl orthobenzoate, ethyl orthobenzoate and the like are preferable.

(2) R ³ R ⁴ C (OR ⁵ ) ₂ (wherein R ³ and R ⁵ are each a hydrocarbon residue having 1 to 12 carbon atoms, and R ⁴ is hydrogen or 1 to 12 carbon atoms.
Is a hydrocarbon residue of. Two R ^5's may be the same or different. At least two members of R ³ , R ⁴ and R ⁵ may be linked to each other to form a ring. ) This compound is a compound generally called a ketal when both R ³ and R ⁴ are hydrocarbon residues and an acetal when R ⁴ is hydrogen. Further, when ethylene glycol is used as an example in which R ^{5 s} are bonded to each other, they are called ethylene ketal or ethylene acetal.

Specific examples of such compounds are as follows.

(A) 2,2-dimethoxypropane, 2,2-diethoxypropane, 2,2-dimethoxy-4-methylpentane, 1,1-dimethoxycyclohexane, 1,1-dimethoxy-1-phenylethane, diphenyldimethoxymethane , Ketal compounds such as diphenylethylene ketal, and (b) acetal compounds such as 1,1-dimethoxyethane, 3,3-dimethoxypropane, phenyldimethoxymethane, phenyldiethoxymethane, and phenylethyleneacetal.

Among these, compounds having phenyl at the α-position, that is, compounds such as diphenyldimethoxyethane, diphenyldiethoxymethane, 1,1-dimethoxy-1-phenylmethane, and phenyldimethoxymethane are preferable.

^{(3) R 6 R 7 R} 8 C (OR 9) ( wherein, R ⁶ and R ⁹ is a hydrocarbon residue having 1 to 12 carbon atoms respectively, R ⁷ and R ⁸ are each hydrogen or C 1 -C 12 which is a hydrocarbon residue .R ^6,
At least two of R ⁷ , R ⁸ and R ⁹ may be linked to each other to form a ring. ) This compound is commonly referred to as an ether.

Specifically, diethyl ether, diisoamyl ether, diphenyl ether, 1-methoxy-1-phenylmethane, 1-methoxy-1-phenylethane, 1,1-
Examples include diphenyl-1-methoxymethane, 1,1-diphenyl-1-methoxyethane, 1,1-diphenyl-1-ethoxyethane, 1-methoxy-1,1,1-triphenylmethane and the like. Among these, those having a phenyl group at the α-position, that is, 1-methoxy-1-phenylmethane, 1-methoxy-1-phenylethane, 1-methoxy-1-methyl-1-phenylethane, 1, 1-diphenyl-1-methoxymethane, 1,
1-diphenyl-1-methoxyethane, 1,1-diphenyl-1-ethoxymethane and the like are compounds.

The addition amount of the component (A ₃ ) is the same as that of the organoaluminum compound (A
₂ ) 0.01 to 1.0 mol, preferably 0.05 to 0.5 mol, per 1 mol.

The catalyst according to manufacturing the invention the catalyst is formed by contacting the component _{(A 1) ~ (A 3} ). It is desirable that the component (A ₃ ) itself or a solution obtained by dissolving or diluting the component (A ₃ ) in an organic solvent is separately injected into the reaction system independently of the components (A ₁ ) and (A ₃ ). However, the component (A
_{When 3} ) does not interfere with the component (A ₁ ) or the component (A ₂ ) preliminarily brought into contact with each other, it can be mixed and injected with these components.

Copolymerization of Ethylene and Olefin Olefin As specific examples of the olefin having 3 or more carbon atoms to be copolymerized with ethylene by the catalyst of the present invention, propylene,
Examples include butene-1, pentene-1, hexene-1, 4-methyl-pentene-1, heptene-1, octene-1, decene-1. Preferred olefins have 3 to 10 carbon atoms. Also, a mixture of the above olefins can be used.

The amount of olefin used relative to ethylene varies depending on the required polymer density, but is generally 1 to 50 mole percent.

Polymerization conditions Copolymerization is carried out under gas phase polymerization conditions. Therefore, the process of the present invention is carried out in the vapor phase polymerization form in the absence of a hydrocarbon solvent. As the polymerization apparatus to be used, any one such as a fluidized bed type, a stirring tank type, etc. can be used. Polymerization temperature is 3
A temperature of 0 to 95 ° C, preferably 80 to 90 ° C is suitable.
Further, hydrogen can be used supplementarily as the molecular weight modifier.

Produced Copolymer The ethylene-olefin copolymer produced according to the present invention has a polymer density of 0.900 to 0.945 g / c.
m ³ , usually 0.915 to 0.935 g / cm ³ .

Experimental Example Example-1 Synthesis of Component (A ₁ ) 75 ml of sufficiently purified n-heptane was charged into a 1 liter flask sufficiently purged with nitrogen, and anhydrous Mg Cl ₂ (a) (ball mill) was placed therein. at that milled 24 hours) 10 grams and Ti (O-n C ₄ H
₉ ) Introduce 10 ml of ₄ (b), and add 3 at 70 ° C.
The reaction was allowed for 0 minutes. Then, n-butanol (c) 5.
A mixture of 4 ml of 5.4 ml of n-heptane was introduced from a spray nozzle for 10 seconds so as to form droplets of 140 μm, and reacted at 70 ° C. for 1 hour.
2.3 ml of TiCl ₄ (d) was introduced therein and reacted for 1 hour. Then, 9 ml of methyl hydrogen polysiloxane (e) was introduced, and 90
The reaction was carried out at 0 ° C for 2 hours. After the reaction was completed, a part of the reaction mixture was taken out and the Ti content in the catalyst component was measured.
It was 9 weight percent. The average particle size was measured by the sedimentation method and found to be 27.4 microns.

Copolymerization of ethylene-butene-1 A device for vapor phase polymerization disclosed in Example 1 of JP-A-57-73011 is charged with sufficiently purified polyethylene powder, and then triethylaluminum (component (component ( A ₂ )) 100 mg, (C ₆ H ₅ ) ₂ C (OC
40 mg of H ₃ ) ₂ (component (A ₃ )) and 10 mg of the solid component (component A ₁ ) synthesized above were introduced. Then, introduce H ₂ at 0.8 kg / cm ² ,
At 85 ° C., introduction of an ethylene-butene-1 mixed gas containing butene-1 at 10% by volume was started, and polymerization was carried out at a total pressure of 9 kg / cm ² and 85 ° C. for 2.5 hours. 25
3 grams of polymer were obtained. MFR = 1.7 (g /
10 minutes) and polymer density = 0.922 (g / cm ³ ). When the amount of extraction with boiling hexane was examined, 5.
It was 5 weight percent. The polymer average particle diameter was 786 microns.

In the polymerization condition of Comparative Example 1 in Example 1, except that was not used _{(C 6 H 5) 2 C} (OCH 3) 2 (A 3), was carried out in exactly the same way as in the polymerization. 279 grams of polymer were obtained. MFR = 2.8 (g / 10
Min), polymer density = 0.928 (g / cm ³ ),
The amount of hexane extracted was 11.7 weight percent.

In the manufacture of components of Example -1 Example -2 component _{(A 1) (A 1)} , using ethanol 3.4 ml instead of n- butanol usage Ti Cl ₄ to 25 ml Except not using methyl hydrogen polysiloxane,
The component (A ₁ ) was produced in exactly the same manner. The Ti content was 6.8 weight percent and the average particle size was 27.6 microns.

Ethylene-Propylene Copolymerization Under the polymerization conditions of Example-1, ethylene-butene-1
Ethylene instead of the mixed gas - using propylene gas _{mixture, (C 6 H 5) 2} C (OCH 3) 2 (C 6 H 5) in place of _{(A 3) C (OCH 3} ) 3 (A 3) Polymerization was performed in exactly the same manner except that 32 mg was used. 306
Grams of polymer were obtained.

MFR = 1.9 (g / 10 minutes), polymer density = 0.9
21 (g / cm ³ ), boiling hexane extraction = 6.9 weight percent, polymer average particle size = 877 microns.

Example -3 ethylene - like the polymerization conditions hexene-1 copolymer in Example 1, the component (A _2),
(A ₃ ) and component (A ₁ ) were introduced respectively. H ₂
0.3 kg / cm ^{2 was} introduced, then 16 ml of hexene-1 was introduced, and further ethylene was introduced to give a total pressure of 5
Polymerization was initiated at kg / cm ² . After the initiation of the polymerization, 16 ml of hexene-1 was introduced every 30 minutes. The polymerization time was 2.5 hours. 154 grams of polymer were obtained. MFR = 1.8 (g / 10 minutes), polymer density = 0.921 (g / cm ³ ), boiling hexane extraction amount,
It was 6.2 weight percent.

Comparative Example -2 ethylene - at polymerization conditions hexene-1 copolymer Example -3, components (A ₃₎ (C ₆
Polymerization was performed in exactly the same manner except that H ₅ ) ₂ C (OCH ₃ ) ₂ was not used. 176 grams of polymer were obtained. MFR = 3.1 (g / 10 minutes), polymer density = 0.927 (g / cm ³ ), boiling hexane extraction = 9.
It was 8 weight percent.

In preparation of component (A ₁₎ of Example -1 Example -4 component (A _1), Ti (O-
The component (A ₁ ) was prepared in exactly the same manner except that Si (OC ₂ H ₅ ) ₄ was used instead of n C ₄ H ₉ ) ₄ . The Ti content was 6.8 weight percent and the average particle size was 18.3 microns.

Ethylene - In polymerization conditions copolymerized in Example 1 butene _{-1 (C 6 H 5) 2} C (OCH 3) 2 in the place (C
Polymerization was conducted in exactly the same manner except that 37 mg of ₆ H ₅ ) ₂ (CH ₃ ) C (OCH ₃ ) (A ₃ ) was used. 1
72 grams of polymer were obtained. MFR = 2.7 (g
/ 10 minutes), polymer density = 0.923 (g / cm ³ , boiling hexane extraction = 6.9 weight percent) Polymer average particle size 473 microns.

Examples 5 to 8 Polymerization was carried out in the same manner as in Example 1 except that the types and amounts of the component (A ₂ ) and the component (A ₃ ) were changed as shown in Table 1. The results are shown in Table-1.

[Brief description of drawings]

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

Claims (1)

[Claims] 1. A catalyst system comprising a combination of the following components (A ₁ ) to (A ₃ ) is brought into contact with ethylene and an olefin having 3 or more carbon atoms under gas phase polymerization conditions to give a polymer density of 0.
Ethylene-, characterized in that an ethylene-olefin copolymer within the range of 900 to 0.945 g / cm ³ is obtained.
Process for producing olefin copolymer. Component (A ₁ ) A contact product of (a) magnesium dihalide with (b) a compound selected from tetraalkoxytitanium and tetraalkoxysilane is contacted with (c) an alcohol compound, and then (d) TiX ₄ (wherein , X represents a halogen), and the average particle size is 10
Those in the range of micron to 100 micron. Component (A ₂ ) An organoaluminum compound. Component (A ₃₎ the following formula _{(A 3 -1), (A} 3 -2) and (A ₃ -3) is selected from a compound having a CO-R bond. (A ₃ −1) R ¹ C (OR ² ) ₃ (wherein R ¹ and R ² are each 1 to 12 carbon atoms.
Is a hydrocarbon residue of. The three R ² may be the same or different. At least two members of R ¹ and R ² may be linked to each other to form a ring. ^{_{) (A 3 -2) R 3}} R 4 C (OR 5) 2 ( wherein, R ³ and R ^4, carbon atoms respectively 1-12
Is a hydrocarbon residue of R ⁴ , and R ⁴ is hydrogen or a carbon number of 1 to 1.
2 hydrocarbon residue. Two R ^5's may be the same or different. At least two members of R ³ , R ⁴ and R ⁵ may be linked to each other to form a ring. ^{_{) (A 3 -3) R 6}} R 7 R 8 C (OR 9) ( wherein, R ⁶ and R ^9, carbon atoms respectively 1-12
R ⁷ and R ⁸ are each hydrogen or a hydrocarbon residue having 1 to 12 carbon atoms. R ⁶ ,
At least two of R ⁷ , R ⁸ and R ⁹ may be linked to each other to form a ring. )