KR101530487B1 - Method of preparing polyolefins using the same - Google Patents

Abstract

The present invention relates to a process for producing a polyolefin. According to the present invention, an organometallic complex prepared by reacting a cyclopentadienyl ligand compound and an organoaluminum compound is used as a molecular weight modifier in the process for producing a polyolefin polymer, The present invention relates to a method for producing a polyolefin using an organic metal complex compound.

Description

TECHNICAL FIELD The present invention relates to a method for preparing a polyolefin polymer,

The present invention relates to a process for producing a polyolefin, and more particularly, to a process for producing a polyolefin having improved molecular weight by using an organometallic complex prepared by reacting a cyclopentadienyl ligand compound and an organoaluminum compound as a molecular weight modifier in a process for producing a polyolefin polymer The present invention relates to a method for producing a polyolefin using an organic metal complex compound.

Metallocenes have been widely used for various organic catalytic reactions and polymer reactions of various olefins. Particularly, in the case of the use of olefin for polymer reaction, the research on the structural modification has been carried out steadily in view of being a single active site catalyst, and it is very easy to control the catalytic activity, molecular weight and molecular weight distribution There have been many industrial applications in relation to this.

There are some prior art challenges to applying metallocenes to the process, and one of the major research concerns is the production of high molecular weight polyolefins. In the case of a catalyst system which produces a large number of high molecular weight products, a complicated ligand synthesis process must be performed and the polymerization activity is lowered unless the process conditions are adjusted. In order to solve these problems and to increase the activity and the molecular weight of the metallocene catalyst, cocatalyst, carrier condition, and additive control can be performed. In the case of additive control, only a limited number of materials are used in actual processes. Alkylaluminum is a typical additive to the process. This material is used to remove impurities such as moisture in the process and has a disadvantage in that the activity of the metallocene catalyst decreases when a certain level or more is used.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems of the prior art as described above, and it is an object of the present invention to provide a chain propagation agent (CPA) which can improve the molecular weight and is easy to use and easy to manufacture.

The above object of the present invention can be achieved by the present invention described below.

In order to accomplish the above object, the present invention provides a process for preparing a polyolefin polymer under metallocene supported catalyst, which process comprises the step of introducing an organometallic complex as a molecular weight regulator, Metal equivalent ratio is from 0.2 to 1.0.

The organometallic complexes and organometallic complexes according to the present invention can be used as molecular weight modifiers in polymerizing polyolefins having improved molecular weight. These compounds have the advantage of being easy to manufacture and use.

Hereinafter, the present invention will be described in detail.

The present invention relates to a method for producing a polyolefin polymer under a metallocene supported catalyst, which comprises the organometallic complex as a molecular weight regulator,

Wherein the metal to metal ratio of the metal to the catalyst is 0.2 to 1.0.

The organometallic complex may be prepared by reacting a cyclopentadienyl ligand compound represented by the following formula (1) and an organoaluminum compound represented by the following formula (2).

[Chemical Formula 1]

C _p ¹ C _p ² MX ₂

Wherein C _p ¹ and C _p ² are independently a ligand having a cyclopentadienyl group selected from a cyclopentadienyl group, an indenyl group and a fluorenyl group, M is a Group IV element on the periodic table, and X is a halogen element .

(2)

R ₁ R ₂ R ₃ Al

Wherein R ₁ , R ₂ and R ₃ are independently a C ₁ -C ₂₀ alkyl group, hydrogen or halogen, and at least one of R ₁ , R ₂ and R ₃ is an alkyl group.

The present invention also provides an organometallic complex or organometallic complex molecular weight control agent represented by the following general formula (3), (4), (5), (6), (7)

(3)

C _p ¹ C _p ² MA

[Chemical Formula 4]

C _p ¹ C _p ² MAX

[Chemical Formula 5]

C _p ¹ C _p ² MAB

[Chemical Formula 6]

C _p ¹ C _p ² M (L) AlR ₁ R ₂ R ₃

(7)

C _p ¹ C _p ² MX (L) AlR ₁ R ₂

[Chemical Formula 8]

C _p ¹ C _p ² M (X) (L) AlR ₁ R ₂ R ₃

In the above formulas, C _p ¹ and C _p ² are independently a ligand having a cyclopentadienyl group selected from a cyclopentadienyl group, an indenyl group and a fluorenyl group, M is a Group IV element on the periodic table, A, B and X are M is a functional group bonded to M, X is a halogen element, A and B are independently a C ₁ to C ₂₀ alkyl group or hydrogen, and (L) means a carbon chain alkylene bonded to both M and Al And R ₁ , R _2, and R ₃ are independently a C ₁ to C ₂₀ alkyl group, hydrogen, or halogen.

The organometallic complex may exist in the form of a mixture with organoaluminum represented by the following general formula (9). When the organometallic complex is separated through recrystallization, the organometallic complexes of the general formulas (3) to (8) can be obtained.
[Chemical Formula 9]
R ₁ R ₂ R ₃ Al
In Formula 9, R ₁ , R _2, and R ₃ are independently a C ₁ to C ₂₀ alkyl group or a halogen, and the C ₁ to C ₂₀ alkyl group may include a heteroatom.

The molecular weight regulator thus formed may be an organometallic or an organobimetallic complex of a transition metal of Group 4 and organoaluminum, and is a composition modified from the initial chemical structures and characteristics of Formulas (1) and (2) And the like.

In addition, it is preferable that the center metal is reduced to an oxidation number of +2 to +4, particularly preferably +3.

The cyclopentadienyl ligand compound is preferably selected from the group consisting of biscyclopentadienyl titanium dichloride, biscyclopentadienyl zirconium dichloride, biscyclopentadienyl hafnium dichloride, bisindenyl titanium dichloride and bis-fluorenyl titanium dichloride. , And among them, biscyclopentadienyltitanium dichloride is more preferable.

The organoaluminum compound is selected from the group consisting of trimethylaluminum, triethylaluminum, tripropylaluminum, triisopropylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, dimethylaluminum chloride, diethylaluminum chloride, dipropylaluminum chloride, It is preferably selected from the group consisting of butyl aluminum chloride, dihexyl aluminum chloride, methyl aluminum dichloride, ethyl aluminum dichloride, propyl aluminum dichloride, and isobutyl aluminum dichloride.

The organometallic complex is prepared by reacting the cyclopentadienyl ligand compound represented by Formula 1 and the organoaluminum compound represented by Formula 2.

The reaction is carried out at a temperature of -200 to 300 ° C and for 0.01 to 200 hours. More preferably -80 to 50 < 0 > C and for 0.5 to 72 hours. When the reaction is carried out at a temperature lower than the above temperature range, the reaction may proceed slowly or complicate the stirring and temperature control process, and if the reaction is carried out at a high temperature, the structure of the final product may be affected. In addition, when the reaction is performed in a time shorter than the above range, the reaction may be terminated before the desired structure is formed. If the reaction is performed longer, the reaction time is consumed since the reaction is terminated.

The content ratio of the cyclopentadienyl ligand compound to the organoaluminum compound is preferably 1: 0.1 to 1: 100. When the organoaluminum compound is used in an amount less than the above range, it may not be possible to see the optimum additive effect on the activity and the molecular weight, and if it is used more, the manufacturing cost increases and it is inefficient.

Examples of the reaction solvent include aromatic hydrocarbons such as toluene, xylene, monochlorobenzene and benzene, hydrocarbons such as pentane, hexane, heptane and octane, ethers such as diethylether, methylbutylether, dimethylglycol and tetrahydrofuran, , Trichloroethane, chloromethane, dichloromethane, trichloromethane, chloroform and the like, but is not limited thereto.

In the process for producing an organometallic complex, there can be mentioned aromatic hydrocarbons such as toluene, xylene, monochlorobenzene and benzene, hydrocarbons such as pentane, hexane, heptane and octane, ethers such as diethylether, methylbutylether, dimethylglycol and tetrahydrofuran Recrystallization and washing with a solvent selected from the group consisting of dichloromethane, dichloroethane, trichloroethane, chloromethane, dichloromethane, trichloromethane, and chloroform.

The organometallic complexes thus prepared are used in a process for producing a polyolefin polymer.

It is preferable that the content of M in the organometallic complex compound added to the step is 0.001-10 μmol per 1 kg of the polyolefin produced in the step. If the amount is less than the above range, the effect of controlling the molecular weight may be insignificant. If the amount is larger than the above range, the production amount may be decreased and the cost may increase.

Applicable polyolefin polymerization processes can be used in the form of bulk polymerization, suspension polymerization, gas phase polymerization, polymerization using a critical fluid, and the like. Other additives may be added to the polymerization for the purpose of removing water and preventing electrification.

The present invention provides a polyolefin polymer prepared by using the organometallic complex as a molecular weight modifier.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope and spirit of the invention as disclosed in the accompanying claims. Changes and modifications may fall within the scope of the appended claims.

[Example]

≪ Preparation of molecular weight regulator &

Example 1

1.25 g of bis (cyclopentadienyl) titanium dichloride was added to a 250 ml round-bottomed flask, 10 ml of toluene was added, and the mixture was stirred. 10 ml of triisobutyl aluminum (1 M in hexane) was added thereto, and the mixture was stirred at room temperature for 3 days. The solvent was removed in vacuo to give a blue liquid mixture. As a result, it was found that titanocene was reduced to +3, which was not oxidized or changed in color in the mixture state.

For separation, the material which was blown off at 50 ~ 60 ℃ was removed and recrystallized in a small amount of hexane at -78 ℃ to remove most of the organoaluminum material and to obtain the material of titanocene substituted with isobutyl group.

_{^{1 H NMR (CDCl 3, 500MHz}} ): 7.26 (br s, 10H), 1.96 (m, 2H), 1.35 (m, 1H), 1.16 (m, 2H), 1.00 (m, 1H), 0.90 (m, 2H), 0.41 (d, 2H)

Example 2

1.25 g of bis (cyclopentadienyl) titanium dichloride was added to a 250 ml round-bottomed flask, 10 ml of toluene was added, and the mixture was stirred. 10 ml of triisobutyl aluminum (1 M in hexane) was added thereto, and the mixture was stirred at room temperature for 3 days. The solvent was removed in vacuo to give a blue liquid mixture. As a result, it was found that titanocene was reduced to +3, which was not oxidized or changed in color in the mixture state. This material was diluted to 0.5 mM in toluene and used as is.

Example 3

The procedure of Example 2 was repeated, except that 5 ml of 1 M in hexane was used in Example 2.

Example 4

Example 2 was carried out in the same manner as in Example 2, except that 20 ml of triisobutylaluminum (1M in hexane) was used.

Example 5

1.25 g of bis (cyclopentadienyl) titanium dichloride was added to a 250 ml round-bottomed flask, 10 ml of toluene was added, and the mixture was stirred. 10 ml of triethyl aluminum (1M in hexane) was added thereto, and the mixture was stirred at room temperature for 3 days. The solvent was removed in vacuo and the resulting material was diluted to 0.5 mM in toluene and used as is.

Example 6

The procedure of Example 5 was repeated except that 5 ml of trimethylaluminum (2M in hexane) was used in Example 5.

Example 7

1.25 g of bis (cyclopentadienyl) titanium dichloride was added to a 250 ml round-bottomed flask, 10 ml of toluene was added, and the mixture was stirred. 10 ml of trioctyl aluminum (1M in hexane) was added thereto, and the mixture was stirred at room temperature for 3 days. The solvent was removed in vacuo to give a blue liquid mixture. As a result, it was found that titanocene was reduced to +3, which was not oxidized or changed in color in the mixture state. This material was diluted to 0.5 mM in toluene and used as is.

^{It was} confirmed by ¹ H NMR that the mixture of bis (cyclopentadienyl) octyltitanium, dioctylaluminum chloride and trioctylaluminum was a mixture of bis (cyclopentadienyl) octyltitanium and dioctylaluminum chloride.

¹ H NMR (CDCl ₃ , 500 MHz): 7.31 (br s, 10H), 2.43 (d, 4H), 1.95-1.2

≪ Preparation of catalyst >

Example 8

3 g of silica gel (Sylopol 2212, Grace Davison) was charged into the reactor, and 10 ml of toluene was added thereto, followed by stirring at 70 ° C. 15 ml of MAO (10 wt% in toluene) was added thereto, and the reaction was allowed to proceed for 2 hours. Then, the unreacted material was washed with toluene. To this was added 0.54 mmol of [tBu-O- (CH ₂ ) ₆ -C ₅ H ₄ ] ₂ ZrCl ₂ and [methyl (6-t-butoxyhexyl) silyl (η ⁵ -tetramethyl C _p ) Amido)] TiCl ₂ compound was dissolved in toluene, and the mixture was stirred at 50 ° C for 1 hour and then washed with toluene. 0.9 mmol of trityl tetrakis (pentafluorophenyl) borate was added thereto, reacted at 50 ° C for 1 hour, and then washed with toluene. Vacuum drying under the same conditions yielded 5.6 g of the dried final catalyst.

≪ Preparation of Polymer &

Example 9

2 l The high-pressure reactor was exchanged with nitrogen for 1 hour at 60 ° C, and then 1 l of purified hexane was added thereto. 0.6 ml of triethylaluminum (1M in hexane) for water removal was injected, and 5 mg (0.65 μmol transition metal content) of the catalyst prepared in Example 8 was suspended in hexane and introduced through a sample container connected to the reactor. Subsequently, 0.26 ml (0.13 μmol Ti content) of the solution prepared in Example 1 and diluted in toluene at a concentration of 0.5 mM Ti was added. Thereafter, ethylene was continuously charged at 80 DEG C and polymerization was carried out for 2 hours while maintaining the pressure at 9 bar. Ethylene in the reactor was removed, separated and dried to obtain a final polymer.

Example 10

The procedure of Example 9 was repeated except that 1.3 ml (0.65 μmol Ti content) of the reagent prepared in Example 2 and having a concentration of 0.5 mM was added instead of the reagent prepared in Example 1.

Example 11

The procedure of Example 9 was repeated except that 0.26 ml (0.13 탆 ol Ti content) of the reagent prepared in Example 2 at a concentration of 0.5 mM was added instead of the reagent prepared in Example 1.

Example 12

The procedure of Example 9 was repeated except that the reagent prepared in Example 3 was added in the same amount (0.13 μmol Ti content) instead of the reagent prepared in Example 1.

Example 13

The procedure of Example 9 was repeated except that the reagent prepared in Example 4 was replaced by the same amount (0.13 mu mol Ti content) of the reagent prepared in Example 1.

Example 14

The procedure of Example 10 was repeated, except that the reagent prepared in Example 5 was added in the same amount (0.13 μmol Ti content) instead of the reagent prepared in Example 2.

Example 15

The procedure of Example 11 was repeated except that the reagent prepared in Example 5 was added in the same amount (0.65 μmol Ti content) instead of the reagent prepared in Example 2.

Example 16

The procedure of Example 10 was repeated except that the reagent prepared in Example 6 was added in the same amount (0.13 μmol Ti content) instead of the reagent prepared in Example 2.

Example 17

The procedure of Example 11 was repeated except that the reagent prepared in Example 6 was added in the same amount (0.65 μmol Ti content) instead of the reagent prepared in Example 2.

Example 18

The procedure of Example 10 was repeated except that the reagent prepared in Example 7 was replaced by the same amount (0.13 mu mol Ti content) of the reagent prepared in Example 2.

Example 19

The procedure of Example 11 was repeated, except that the reagent prepared in Example 7 was added in the same amount (0.65 μmol Ti content) instead of the reagent prepared in Example 2.

Comparative Example 1

2 l The high-pressure reactor was exchanged with nitrogen for 1 hour at 60 ° C, and then 1 l of purified hexane was added thereto. 0.6 ml of triethylaluminum (1M in hexane) for water removal was injected, and 5 mg (0.65 μmol transition metal content) of the catalyst prepared in Example 8 was suspended in hexane and introduced through a sample container connected to the reactor. Thereafter, ethylene was continuously charged at 80 DEG C and polymerization was carried out for 2 hours while maintaining the pressure at 9 bar. Ethylene in the reactor was removed, separated and dried to obtain a final polymer.

Comparative Example 2

2 l The high-pressure reactor was exchanged with nitrogen for 1 hour at 60 ° C, and then 1 l of purified hexane was added thereto. 0.6 ml of triethylaluminum (1M in hexane) for water removal was injected, and then 0.26 ml (0.13 μmol Ti content) of the reagent prepared in Example 1 and diluted in toluene at a concentration of 0.5 mM Ti was added. Thereafter, ethylene was continuously charged at 80 DEG C and polymerization was carried out for 2 hours while maintaining the pressure at 9 bar. No polyethylene was produced in the reactor.

Comparative Example 3

2 l The high-pressure reactor was exchanged with nitrogen for 1 hour at 60 ° C, and then 1 l of purified hexane was added thereto. 0.6 ml of triethylaluminum (1 M in hexane) for water removal was injected, and then 0.26 ml (0.13 탆 mol Ti content) of the reagent prepared in Example 1 and diluted in toluene at a concentration of 0.5 mM Ti, (Pentafluorophenyl) borate (trityl tetrakis (pentafluorophenyl) borate). Thereafter, ethylene was continuously charged at 80 DEG C and polymerization was carried out for 2 hours while maintaining the pressure at 9 bar. Ethylene in the reactor was removed, separated and dried to obtain 0.4 g of final polymer.

[Experimental Example]

* MI (Melting Index): Measured according to the ASTM D1238 method.

division catalyst Complex formation Polymerization Example Organic metal
Complex Organic Al compound Complex / catalyst metal equivalent ratio Active (Kg PE / g cat) MI (21.6 Kg)
(g / 10 min) Example 9 Example 8 Example 1 TIBA ¹⁾ 0.2 34 3.72 Example 10 Example 8 Example 2 TIBA 0.2 36 3.41 Example 11 Example 8 Example 2 TIBA 1.0 35 0.93 Example 12 Example 8 Example 3 TIBA
(0.5 times) 0.2 34 3.5 Example 13 Example 8 Example 4 TIBA
(Twice) 0.2 37 3.2 Example 14 Example 8 Example 5 TEA ²⁾ 0.2 37 1.49 Example 15 Example 8 Example 5 TEA 1.0 18 0.00 Example 16 Example 8 Example 6 TMA ³⁾ 0.2 36 1.16 Example 17 Example 8 Example 6 TMA 1.0 24 0.15 Example 18 Example 8 Example 7 TOA ⁴⁾ 0.2 39 5.47 Example 19 Example 8 Example 7 TOA 1.0 35 1.6 Comparative Example 1 Example 8 - - - 39 14.5 Comparative Example 2 - Example 1 TIBA - 0 - Comparative Example 3 Example 1 TIBA - 0 (0.4 g) 65

* Day

1) TIBA: triisobutyl aluminum

2) TEA: triethyl aluminum

3) TMA: trimethyl aluminum

4) TOA: trioctyl aluminum

As shown in Table 1, when a polyolefin polymer is prepared by using a complex or a composition having a metal equivalent ratio of the metal of the complex prepared by the present invention and the catalyst of 0.2 to 1.0 as a molecular weight modifier, the polyolefin It can be seen that when the polymer is prepared (Comparative Example 1), the melt index shows a low value without lowering the activity of the catalyst, and accordingly, a polyolefin having a high weight average molecular weight is produced. In addition, even when changing the type of alkylaluminum used in the preparation of the complex, it can be seen that when the amount of the alkylaluminum is changed in the polymerization, the molecular weight is sufficiently controlled. As shown in Comparative Examples 2 and 3, when the polymerization was carried out without adding the supported catalyst during the polymerization, no material was prepared using only the complex compound of the present invention, and a trace amount of the product obtained by introducing the borate promoter had a low molecular weight. It can be seen that the complexes themselves do not produce a high molecular weight substance but serve as an additive to be used together with the olefin polymerization catalyst or the olefin polymerization supported catalyst.

Claims (7)

A method for producing a polyolefin polymer under a metallocene supported catalyst, the method comprising, as a molecular weight regulator, an organometallic complex,
The metal to metal ratio of the metal of the complex compound to the metal is 0.2 to 1.0,
The organometallic complex is a molecular weight modifier for metallocene catalyzed polymerization of a polyolefin, which is prepared by reacting a cyclopentadienyl ligand compound represented by the following formula (1) and an organoaluminum compound represented by the following formula (2) Is present in the form of a mixture with an organoaluminum represented by the following formula (9)
[Chemical Formula 1]
C _p ¹ C _p ² MX ₂
(2)
R ₁ R ₂ R ₃ Al
In the above formulas, C _p ¹ and C _p ² are independently a ligand having a cyclopentadienyl group selected from a cyclopentadienyl group, an indenyl group and a fluorenyl group, M is a Group IV element on the periodic table, A is a bond X is a halogen element, A is a C ₁ -C ₂₀ alkyl group or hydrogen, and R ₁ , R _2, and R ₃ are independently a C ₁ -C ₂₀ alkyl group, hydrogen, or halogen.
[Chemical Formula 9]
R ₁ R ₂ R ₃ Al
In Formula 9, R ₁ , R _2, and R ₃ are independently a C ₁ to C ₂₀ alkyl group or a halogen, and the C ₁ to C ₂₀ alkyl group may include a heteroatom. The method according to claim 1,
Wherein the metallocene supported catalyst is a supported catalyst prepared by charging an alkylaluminoxane co-catalyst to a carrier, then introducing a metallocene compound, and introducing a borate co-catalyst. The method according to claim 1,
Wherein the organometallic complex is represented by the following Chemical Formula 3, 4, 5, 6, 7 or 8
(3)
C _p ¹ C _p ² MA
[Chemical Formula 4]
C _p ¹ C _p ² MAX
[Chemical Formula 5]
C _p ¹ C _p ² MAB
[Chemical Formula 6]
C _p ¹ C _p ² M (L) AlR ₁ R ₂ R ₃
(7)
C _p ¹ C _p ² MX (L) AlR ₁ R ₂
[Chemical Formula 8]
C _p ¹ C _p ² M (X) (L) AlR ₁ R ₂ R ₃
In the above formulas, C _p ¹ and C _p ² are independently a ligand having a cyclopentadienyl group selected from a cyclopentadienyl group, an indenyl group and a fluorenyl group, M is a Group IV element on the periodic table, A, B and X Is a functional group bonded to M, X is a halogen element, A and B are independently a C ₁ -C ₂₀ alkyl group or hydrogen, (X) means a halogen bonded to both M and Al, (L) means a carbon chain alkylene bonded to both M and Al, and R ₁ , R ₂ and R ₃ are independently a C ₁ to C ₂₀ alkyl group, hydrogen or halogen. The method according to claim 1,
The cyclopentadienyl ligand compound is preferably selected from the group consisting of biscyclopentadienyl titanium dichloride, biscyclopentadienyl zirconium dichloride, biscyclopentadienyl hafnium dichloride, bisindenyl titanium dichloride and bis-fluorenyl titanium dichloride. Lt; RTI ID = 0.0 > polyolefin < / RTI > polymer. The method according to claim 1,
The organoaluminum compound is selected from the group consisting of trimethylaluminum, triethylaluminum, tripropylaluminum, triisopropylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, dimethylaluminum chloride, diethylaluminum chloride, dipropylaluminum chloride, Wherein the polyolefin is selected from the group consisting of butyl aluminum chloride, dihexyl aluminum chloride, methyl aluminum dichloride, ethyl aluminum dichloride, propyl aluminum dichloride, and isobutyl aluminum dichloride. delete The method according to claim 1,
Wherein the content of M of the organometallic complex compound is added in a proportion of 0.001 to 10 mu mol per 1 kg of the produced polyolefin.